Abstract In this paper we focused on the comparative study of three very popular and most recently developed nature inspired evolutionary algorithms namely Biogeography based optimization algorithm (BBO), Flower pollination algorithm (FPA) and Artificial bee colony optimization algorithm (ABC) for developing a model of 6 layers thin broadband (0.2-20GHz) microwave absorber. The model is optimized for oblique wide angle of incidence (450, 600) taking both TE and TM polarization of the electromagnetic wave under consideration. The primary goal of our design is to minimizing the overall reflection coefficient of the absorber and its total thickness by selecting the proper layer of materials from a predefined database of existing materials. 8 different models are presented and synthesize considering both these design consideration simultaneously and for only overall reflection coefficient of the absorber while total thickness is not taken into consideration during optimization for each cases. The optimum values of all the significant parameters of the multilayer absorber for different models have been compared and tabulated using BBO, FPA and ABC algorithms which established the superiority of our proposed design. Keywords: Multilayer microwave absorber, Oblique incidence, Broadband, Evolutionary algorithms, Arbitrary polarization
A Compact Multiband Metamaterial based Microstrip Patch Antenna for Wireless ...IJERA Editor
In this paper, a metamaterial based compact multiband microstrip antenna is proposed which can give high gain and directivity. Metamaterials are periodic structures and have been intensively investigated due to the particular features such as ultra-refraction phenomenon and negative permittivity and/or permeability. A metamaterialbased microstrip patch antenna with enhanced characteristics and multi band operation will be investigated in this work. The multiple frequency operation will be achieved by varying the capacitance of the metamaterial structure with the help of metallic loadings placed in each metamaterial unit cells. The potential impacts will be miniaturization, reduced cost and reduced power consumption since multiple antennas operating at different frequencies are replaced by a single antenna which can operate at multiple frequencies. The proposed microstrip patch antenna will have its frequencies of operation in the L, S and C bands. The proposed structure is simulated using Agilent Advanced Design System (ADS) 2011.05. It is then fabricated on the FR4 substrate and the performance of the fabricated antenna is measured using the Vector Network Analyzer (VNA)
Design of wide band microstrip array antenna using direct coupled techniqueeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
A study on the V-shaped microstrip patch antenna for multiple-input multiple-output (MIMO) communication system based on the antenna orientation is performed. First the microstrip patch antenna operating at 2.45 GHz is calculated and simulated. Next, multiple elements of antennas for MIMO system is simulated and discussed. V-shaped with 45 degree slanted inward and outward is studied. The antenna properties are analyzed and compact antenna design is determined based on the simulation results. The dresults show the gap between antennas can be optimized to 1 mm while maintaining low mutual coupling. The gain of the MIMO antenna is 8.42 dBi. The simulated return losses, together with the radiation patterns, are presented and discussed.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Self affine rectangular fractal antenna with uc-ebg structure-2IAEME Publication
This document discusses the design and simulation of a self-affine rectangular fractal antenna with electromagnetic bandgap (EBG) structures. The antenna is designed on a substrate with a dielectric constant of 4.4 and thickness of 1.6mm. The basic rectangular patch antenna is modified through two iterations of fractal geometry to produce a multiband antenna. EBG structures are added surrounding the antenna. Simulation results show the antenna resonating at multiple frequencies with increased iteration, providing bandwidth enhancement and size reduction compared to the basic patch antenna. Good agreement is achieved between simulated and experimentally measured results.
Enhancing the Radiation Pattern of Phase Array Antenna Using Particle Swarm O...IOSR Journals
The document describes a study that uses particle swarm optimization to enhance the radiation pattern of a phase array antenna by minimizing sidelobe levels. It first provides background on issues with high sidelobes in phase array antennas, such as power losses and interference. It then summarizes previous research using techniques like genetic algorithms for antenna array optimization. The study models the radiation pattern of linear arrays with different element numbers and calculates gain, finding that gain increases with more elements. However, sidelobe levels also increase relatively. Therefore, the study proposes using particle swarm optimization to optimize current excitation and control sidelobe levels while maintaining a narrow beamwidth.
IRJET - Review of Various Multi-Focus Image Fusion MethodsIRJET Journal
This document provides an overview of multi-focus image fusion methods. It discusses various multi-focus image fusion techniques in both the spatial and frequency domains. It reviews several papers on multi-focus image fusion using different methods like region mosaicking on laplacian pyramid (RMLP), discrete wavelet transform (DWT), principal component analysis (PCA), discrete cosine transform (DCT), and implementation on field programmable gate arrays (FPGAs). The document compares the advantages and issues of the techniques discussed in the reviewed papers. It provides context on applications of image fusion in areas like remote sensing, medical imaging, and more.
Modeling of RF Power Amplifier with Memory Effects using Memory PolynomialIJERA Editor
Power Amplifier is one of the most important component in a communication system. It is inherently non-linear and having memory effects. But current communication systems require highly linear response as nonlinearities contribute to gain compression and produce harmonic distortion. But for linearization of power amplifier, it is necessary to model PA's memory behavior accurately. So in this paper, a memory polynomial based power amplifier model is presented which takes into account its memory effects for wideband applications. This paper also presents a comparison of proposed model with actual RF power amplifier in terms of power spectral density and AM/AM characteristics. Simulation results shows its efficiency and accuracy.
A Compact Multiband Metamaterial based Microstrip Patch Antenna for Wireless ...IJERA Editor
In this paper, a metamaterial based compact multiband microstrip antenna is proposed which can give high gain and directivity. Metamaterials are periodic structures and have been intensively investigated due to the particular features such as ultra-refraction phenomenon and negative permittivity and/or permeability. A metamaterialbased microstrip patch antenna with enhanced characteristics and multi band operation will be investigated in this work. The multiple frequency operation will be achieved by varying the capacitance of the metamaterial structure with the help of metallic loadings placed in each metamaterial unit cells. The potential impacts will be miniaturization, reduced cost and reduced power consumption since multiple antennas operating at different frequencies are replaced by a single antenna which can operate at multiple frequencies. The proposed microstrip patch antenna will have its frequencies of operation in the L, S and C bands. The proposed structure is simulated using Agilent Advanced Design System (ADS) 2011.05. It is then fabricated on the FR4 substrate and the performance of the fabricated antenna is measured using the Vector Network Analyzer (VNA)
Design of wide band microstrip array antenna using direct coupled techniqueeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
A study on the V-shaped microstrip patch antenna for multiple-input multiple-output (MIMO) communication system based on the antenna orientation is performed. First the microstrip patch antenna operating at 2.45 GHz is calculated and simulated. Next, multiple elements of antennas for MIMO system is simulated and discussed. V-shaped with 45 degree slanted inward and outward is studied. The antenna properties are analyzed and compact antenna design is determined based on the simulation results. The dresults show the gap between antennas can be optimized to 1 mm while maintaining low mutual coupling. The gain of the MIMO antenna is 8.42 dBi. The simulated return losses, together with the radiation patterns, are presented and discussed.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Self affine rectangular fractal antenna with uc-ebg structure-2IAEME Publication
This document discusses the design and simulation of a self-affine rectangular fractal antenna with electromagnetic bandgap (EBG) structures. The antenna is designed on a substrate with a dielectric constant of 4.4 and thickness of 1.6mm. The basic rectangular patch antenna is modified through two iterations of fractal geometry to produce a multiband antenna. EBG structures are added surrounding the antenna. Simulation results show the antenna resonating at multiple frequencies with increased iteration, providing bandwidth enhancement and size reduction compared to the basic patch antenna. Good agreement is achieved between simulated and experimentally measured results.
Enhancing the Radiation Pattern of Phase Array Antenna Using Particle Swarm O...IOSR Journals
The document describes a study that uses particle swarm optimization to enhance the radiation pattern of a phase array antenna by minimizing sidelobe levels. It first provides background on issues with high sidelobes in phase array antennas, such as power losses and interference. It then summarizes previous research using techniques like genetic algorithms for antenna array optimization. The study models the radiation pattern of linear arrays with different element numbers and calculates gain, finding that gain increases with more elements. However, sidelobe levels also increase relatively. Therefore, the study proposes using particle swarm optimization to optimize current excitation and control sidelobe levels while maintaining a narrow beamwidth.
IRJET - Review of Various Multi-Focus Image Fusion MethodsIRJET Journal
This document provides an overview of multi-focus image fusion methods. It discusses various multi-focus image fusion techniques in both the spatial and frequency domains. It reviews several papers on multi-focus image fusion using different methods like region mosaicking on laplacian pyramid (RMLP), discrete wavelet transform (DWT), principal component analysis (PCA), discrete cosine transform (DCT), and implementation on field programmable gate arrays (FPGAs). The document compares the advantages and issues of the techniques discussed in the reviewed papers. It provides context on applications of image fusion in areas like remote sensing, medical imaging, and more.
Modeling of RF Power Amplifier with Memory Effects using Memory PolynomialIJERA Editor
Power Amplifier is one of the most important component in a communication system. It is inherently non-linear and having memory effects. But current communication systems require highly linear response as nonlinearities contribute to gain compression and produce harmonic distortion. But for linearization of power amplifier, it is necessary to model PA's memory behavior accurately. So in this paper, a memory polynomial based power amplifier model is presented which takes into account its memory effects for wideband applications. This paper also presents a comparison of proposed model with actual RF power amplifier in terms of power spectral density and AM/AM characteristics. Simulation results shows its efficiency and accuracy.
IRJET- Multi-Band Polarization Insensitive Metamaterial Absorber for EMI/EMC ...IRJET Journal
- A multi-band metamaterial absorber was designed that can absorb electromagnetic waves at C-band, X-band, Ku-band, and K-band frequencies.
- The absorber structure consists of two split ring resonators and two square fractal structures on a metal-backed dielectric substrate.
- Simulation results showed high absorption (over 80%) at multiple distinct frequencies, with absorption peaks between 90-99% across the different bands. The absorber also demonstrated polarization-insensitive behavior.
IRJET - Dual Band Low Profile MPA with I-shaped MTM Unit Cell for Satelli...IRJET Journal
This document describes the simulation of a dual-band low-profile microstrip patch antenna with an I-shaped metamaterial unit cell. The antenna is designed to operate at 10.5GHz and 12.2GHz. Simulation results show the antenna achieves a fractional bandwidth of 6.58% at 10.5GHz and 2.41% at 12.2GHz. Peak gains are 4.81dB at 10.5GHz and 1.33dB at 12.2GHz. The metamaterial unit cell provides 46.63% miniaturization of the patch area. The antenna design demonstrates improved bandwidth and gain performance suitable for applications such as satellite communication and radar systems.
Design Study of a Miniaturized Multi-layered Antenna-in-package for 2.4 GHZ ...IJECEIAES
This paper proposes a novel miniaturization technique to enhance the radiation properties of small multi-layer patch antenna used in packaged circuits. The multilayered antenna design is composed of three layers with different shapes. An enhancement on the radiation properties has been obtained by optimizing the geometry of the radiated element and the parasitic conductor of the middle layer. The whole design has been implemented on the FR4 substrate with dielectric constant of 4.4, thickness of 1.6 mm and Copper thickness of 5 m. The first layer is a driven element while second and the third layer are parasitic patch elements. The optimized multilayer antenna has a very small size of . Considering the small size of the antenna, a detailed study of the parameter affecting the radiation has been considered to force the antenna to operate at 2.4 GHz band. Miniaturization techniques based on the current distribution have been also taken into account to shift down the resonant frequency and reduces more and more the antenna size at the designed operating frequency. The miniaturized antenna maintains performant radiation characteristics in terms of reflexion coefficient, bandwidth and directivity. All developed antennas are simulated using the commercial Electromagnetic CST Microwave Studio software. Achieved results demonstrate a good performance with low cost and compact size
Automatic mic adjustment using dc motoreSAT Journals
Abstract
Beamforming theory is used to measure the phase angle between two input signals. Automatic adjustment of height and position of
MIC using dc motors. Horizontal and vertical DC motors are attached with the mic. Microphone array signal processing is to
enhance and extract information carried by acoustic waves received from a number of microphones. Differently placed
microphones are receiving more or less the same signal but with a small time shift. The time delay estimation is calculated using
LabVIEW software.
Keywords - MEMS microphones, beamforming, source localization, DC motor
Dielectric Resonator Reflectarray Antenna Unit Cells for 5G Applications IJECEIAES
This paper presents an investigation for the performance comparison of three different unit cell configurations operating at 26 GHz for 5G applications. The unit cells are cross shape dielectric resonator, cross microstrip patch and cross hybrid dielectric resonator. Verification of the comparison has been done by simulations using commercial Computer Simulation Technology Microwave Studio (CST MWS). The simulated results for reflection phase, slope variation, reflection loss and 10% bandwidth were analyzed and compared. The results indicate that the optimum configuration to be deployed for the reflectarray’s unit element in order to fulfill the 5G requirements of a wide bandwidth is the cross hybrid DRA. This configuration is a combination of cross DRA with cross microstrip patch as the parasitic element in order to tune the phase and provide a wide phase range with smooth variation slope. Cross hybrid DRA provided a wide phase range of 520° with 0.77 dB loss and 10% bandwidth of 160 MHz.
This document describes research on enhancing the performance of microstrip patch antennas using metamaterials. Microstrip patch antennas have advantages like low profile and weight but suffer from narrow bandwidth and low gain. The researchers designed a patch antenna operating at 2GHz on an FR4 substrate. Metamaterial structures like split ring resonators (SRR) and complementary split ring resonators (CSRR) were placed on the patch, substrate, and ground plane. Simulation results showed the metamaterial antenna achieved a bandwidth of 145MHz, an improvement over the 71.1MHz bandwidth of the basic patch antenna. In conclusion, metamaterials can effectively overcome limitations of conventional patch antennas.
Transmission spectra of single ring coupled-waveguide resonator configuration...TELKOMNIKA JOURNAL
Development of optical waveguide resonators have greatly expanded and continues to grow since they have kinds potential applications such as wavelength filtering, switching, coupling and multiplexing. One of resonators, coupled waveguides, ring resonators are designed and operated using various coupling configurations. Ring resonators can be particularly used as wavelength filter if the wavelength can fit a whole multiple time in the circumference of the ring. This article proposes to investigate the transmission spectra from the power source and amplify it in linearized ring resonator configurations and varies the input amplitude on five different wavelengths. With finite difference time domain method, the geometry and power source are simulated to obtain the better result and configuration. The results show the intensity phenomena of filtering in optical circuit.
Performance Investigation and Enhancement of Fiber Bragg Gratingfor Efficient...IOSRJECE
In this paper, the performance of various windowfunctions for Fiber Bragg Grating Sensor (FBGS)is investigated and evaluated in order to get optimized reflection spectrum with high reflectivity and an efficient side lobe suppression for efficient sensing measurement applications.For this purpose, a wide range of design parameters which include grating length and refractive index modulation amplitudehas been chosen to evaluate the sensor design. The performances of the different windowfunctions have been then compared in terms of reflectivity, full width half maximum bandwidth (FWHM), and sidelobe level(SLL) so as to get the most suitable design parametersto be used for sensing measurement.The simulation results presented in this paper show the effectiveness of the optimizedFBG sensor, which can be further implemented for high performance sensing applications.
Time Domain Modelling of Optical Add-drop filter based on Microcavity Ring Re...iosrjce
IOSR Journal of Electronics and Communication Engineering(IOSR-JECE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electronics and communication engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electronics and communication engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
A New Approach for Solving Inverse Scattering Problems with Overset Grid Gene...TELKOMNIKA JOURNAL
This paper presents a new approach of Forward-Backward Time-Stepping (FBTS)
utilizing Finite-Difference Time-Domain (FDTD) method with Overset Grid Generation (OGG)
method to solve the inverse scattering problems for electromagnetic (EM) waves. The proposed
FDTD method is combined with OGG method to reduce the geometrically complex problem to a
simple set of grids. The grids can be modified easily without the need to regenerate the grid
system, thus, it provide an efficient approach to integrate with the FBTS technique. Here, the
characteristics of the EM waves are analyzed. For the research mentioned in this paper, the
‘measured’ signals are syntactic data generated by FDTD simulations. While the ‘simulated’
signals are the calculated data. The accuracy of the proposed approach is validated. Good
agreements are obtained between simulation data and measured data. The proposed approach
has the potential to provide useful quantitative information of the unknown object particularly for
shape reconstruction, object detection and others.
Design of v slotted microstrip patch antenna for yielding improved gain bandw...eSAT Publishing House
This document describes the design of a V-slotted microstrip patch antenna to improve gain and bandwidth. The antenna was designed to operate at 5.9 GHz for WLAN and Wi-Max applications. It uses a single layer substrate with dielectric constant of 2.2. Three V-slots were cut into the rectangular patch to reduce the size while maintaining performance. Simulation results showed the antenna achieved a maximum bandwidth of 1.04 GHz and gain of 6.22 dBi. The V-slotted design improved the gain-bandwidth product over a basic rectangular patch antenna.
Design of v slotted microstrip patch antenna for yielding improved gain bandw...eSAT Journals
Abstract In this paper, a novel antenna design for improvement of patch antenna gain and bandwidth has been proposed.The proposed antenna design is a V-slotted rectangular microstrip patch antenna for yielding improved gain bandwidth product suitable for WLAN and Wi-Max applications. The antenna operates at 5.9 GHz and has the maximum achievable bandwidth obtained about 1.04Ghz and gain of 6.22dBi .The microstrip patch is constructed using a single layer RT/duroid (5880) substrate, having dielectric constant εr = 2.2 and loss tangent tan δ =0.001.A co-axial feed is used and the antenna is simulated using IE3D software from Zeland based on method of moments. Key Words: RMSA, V-slot, Gain-Bandwidth product, WLAN, Wi-Fi
METAMATERIAL STRUCTURE FOR BANDWIDTH IMPROVEMENT Sayahnarahul
The document describes the design of a rectangular microstrip patch antenna operating at 1.881 GHz that uses a split rectangular shaped metamaterial structure to improve bandwidth. The metamaterial structure is designed on an FR-4 substrate and loaded onto the patch antenna. This is expected to increase the antenna's bandwidth to 22.5 MHz while reducing the return loss to -18.175 dB, compared to 4.9 MHz bandwidth and -10.068 dB return loss without the metamaterial. The metamaterial takes advantage of negative permeability to enhance the antenna performance.
Analysis and Design of S-shaped Microstrip Patch AntennaIOSR Journals
Abstract: This paper gives a compact analysis and design of S-shaped Microstrip patch antenna which is best suited for Wi-max application. The analysis and design is simulated over IE3D software Ver. 15.2. We have taken a definite ground plane of 50x70 mm and patch size of 30x50 mm.The substrate thickness is taken as 1.6 mm and dielectric constant of 4.2 and loss tangent of 0.0013. The simulated result shows that the bandwidth is obtained in triple band- 7.79% at 0.262921 GHz band, 13.45% at 1.53034 GHz band and 28.0056% at 2.2382 GHz band. The obtained gain is 3.96 dBi at 2.33945 GHz. The obtained gain and bandwidth is best suited for Wi-max application. Keywords: S shape, Ground plane, Patch Antenna, Triple Band.
Mutual Coupling Reduction between Asymmetric Reflectarray Resonant Elements IJECEIAES
A physically asymmetric reflectarray element has been proposed for wide band operations. The dual resonant response has been introduced by tilting one side of the square path element. The numerical results have been analyzed in the frequency band between 24GHz to 28GHz where a reflection phase range of more than 600° has been achieved. The proposed asymmetric element can produce mutual coupling with adjacent elements on a reflectarray. This effect has been monitored by placing the elements in a mirror configuration on the surface of reflectarray. The single unit cell element results have been compared with conventional 4 element unit cell and proposed mirroring element configuration. The proposed mirroring element technique can be used to design a broadband reflectarray for high gain applications.
Modified Sierpinski Gasket for Wi-Fi and WLAN ApplicationsIJERA Editor
This document describes the design and simulation of a modified Sierpinski gasket fractal antenna for Wi-Fi and WLAN applications. Fractal antennas can provide multiband operation and miniaturization. The designed antenna uses a Sierpinski gasket fractal placed on an Arlon substrate with a line feed. Simulations show the antenna operates in the frequency ranges of 1.75-2.65 GHz and 5.7-7.65 GHz, covering Wi-Fi and WLAN bands. Return loss is below -15 dB and radiation patterns indicate good gain within the operating bands, confirming multiband performance for wireless applications. The fractal design approach allows for a small, low profile antenna suitable for integrated systems
NOVEL METHODOLOGY OF THE ULTRA SONIC BEAM IN LINEAR ARRAY TRANSDUCER FOR HIGH...Journal For Research
In this paper, the focusing of ultrasound beam is considered. Electronic circuitry is considered as support to the theme of the work. The results presented in this paper are notable for improved resolution. The extension of the application diversity is also proposed based on use of Piezo electric transceducers.
Design of a dual-band antenna for energy harvesting applicationjournalBEEI
This report presents an investigation on how to improve the current dual-band antenna to enhance the better result of the antenna parameters for energy harvesting application. Besides that, to develop a new design and validate the antenna frequencies that will operate at 2.4 GHz and 5.4 GHz. At 5.4 GHz, more data can be transmitted compare to 2.4 GHz. However, 2.4 GHz has long distance of radiation, so it can be used when far away from the antenna module compare to 5 GHz that has short distance in radiation. The development of this project includes the scope of designing and testing of antenna using computer simulation technology (CST) 2018 software and vector network analyzer (VNA) equipment. In the process of designing, fundamental parameters of antenna are being measured and validated, in purpose to identify the better antenna performance.
The original document has been moved to a new location. A brief message indicates that the document is no longer available at its original URL and has been relocated elsewhere. No other details are provided about where the document has been moved.
1) The document is a seminar report submitted by Abhimithra Reddy to partially fulfill requirements for a Bachelor of Technology degree in Electronics and Communication Engineering.
2) The report discusses the art of invisible cloaking and was created under the guidance of Ms. Y. Jalajakshi.
3) The report was submitted to the Holy Mary Institute of Technology and Science in India in partial fulfillment of degree requirements from Jawaharlal Nehru Technological University Hyderabad.
This document discusses the concept of invisibility and metamaterials. It contains 5 chapters that cover: 1) an introduction to light and optics concepts like reflection and refraction, 2) the evolution and workings of metamaterials which exhibit negative refraction, 3) how metamaterials are formed, 4) limitations of metamaterials and cloaking, and 5) applications and future prospects of invisibility including cloaking. The abstract outlines how metamaterials can be used to alter light properties to achieve invisibility cloaking. The document also includes acknowledgements, a list of figures, and references.
IRJET- Multi-Band Polarization Insensitive Metamaterial Absorber for EMI/EMC ...IRJET Journal
- A multi-band metamaterial absorber was designed that can absorb electromagnetic waves at C-band, X-band, Ku-band, and K-band frequencies.
- The absorber structure consists of two split ring resonators and two square fractal structures on a metal-backed dielectric substrate.
- Simulation results showed high absorption (over 80%) at multiple distinct frequencies, with absorption peaks between 90-99% across the different bands. The absorber also demonstrated polarization-insensitive behavior.
IRJET - Dual Band Low Profile MPA with I-shaped MTM Unit Cell for Satelli...IRJET Journal
This document describes the simulation of a dual-band low-profile microstrip patch antenna with an I-shaped metamaterial unit cell. The antenna is designed to operate at 10.5GHz and 12.2GHz. Simulation results show the antenna achieves a fractional bandwidth of 6.58% at 10.5GHz and 2.41% at 12.2GHz. Peak gains are 4.81dB at 10.5GHz and 1.33dB at 12.2GHz. The metamaterial unit cell provides 46.63% miniaturization of the patch area. The antenna design demonstrates improved bandwidth and gain performance suitable for applications such as satellite communication and radar systems.
Design Study of a Miniaturized Multi-layered Antenna-in-package for 2.4 GHZ ...IJECEIAES
This paper proposes a novel miniaturization technique to enhance the radiation properties of small multi-layer patch antenna used in packaged circuits. The multilayered antenna design is composed of three layers with different shapes. An enhancement on the radiation properties has been obtained by optimizing the geometry of the radiated element and the parasitic conductor of the middle layer. The whole design has been implemented on the FR4 substrate with dielectric constant of 4.4, thickness of 1.6 mm and Copper thickness of 5 m. The first layer is a driven element while second and the third layer are parasitic patch elements. The optimized multilayer antenna has a very small size of . Considering the small size of the antenna, a detailed study of the parameter affecting the radiation has been considered to force the antenna to operate at 2.4 GHz band. Miniaturization techniques based on the current distribution have been also taken into account to shift down the resonant frequency and reduces more and more the antenna size at the designed operating frequency. The miniaturized antenna maintains performant radiation characteristics in terms of reflexion coefficient, bandwidth and directivity. All developed antennas are simulated using the commercial Electromagnetic CST Microwave Studio software. Achieved results demonstrate a good performance with low cost and compact size
Automatic mic adjustment using dc motoreSAT Journals
Abstract
Beamforming theory is used to measure the phase angle between two input signals. Automatic adjustment of height and position of
MIC using dc motors. Horizontal and vertical DC motors are attached with the mic. Microphone array signal processing is to
enhance and extract information carried by acoustic waves received from a number of microphones. Differently placed
microphones are receiving more or less the same signal but with a small time shift. The time delay estimation is calculated using
LabVIEW software.
Keywords - MEMS microphones, beamforming, source localization, DC motor
Dielectric Resonator Reflectarray Antenna Unit Cells for 5G Applications IJECEIAES
This paper presents an investigation for the performance comparison of three different unit cell configurations operating at 26 GHz for 5G applications. The unit cells are cross shape dielectric resonator, cross microstrip patch and cross hybrid dielectric resonator. Verification of the comparison has been done by simulations using commercial Computer Simulation Technology Microwave Studio (CST MWS). The simulated results for reflection phase, slope variation, reflection loss and 10% bandwidth were analyzed and compared. The results indicate that the optimum configuration to be deployed for the reflectarray’s unit element in order to fulfill the 5G requirements of a wide bandwidth is the cross hybrid DRA. This configuration is a combination of cross DRA with cross microstrip patch as the parasitic element in order to tune the phase and provide a wide phase range with smooth variation slope. Cross hybrid DRA provided a wide phase range of 520° with 0.77 dB loss and 10% bandwidth of 160 MHz.
This document describes research on enhancing the performance of microstrip patch antennas using metamaterials. Microstrip patch antennas have advantages like low profile and weight but suffer from narrow bandwidth and low gain. The researchers designed a patch antenna operating at 2GHz on an FR4 substrate. Metamaterial structures like split ring resonators (SRR) and complementary split ring resonators (CSRR) were placed on the patch, substrate, and ground plane. Simulation results showed the metamaterial antenna achieved a bandwidth of 145MHz, an improvement over the 71.1MHz bandwidth of the basic patch antenna. In conclusion, metamaterials can effectively overcome limitations of conventional patch antennas.
Transmission spectra of single ring coupled-waveguide resonator configuration...TELKOMNIKA JOURNAL
Development of optical waveguide resonators have greatly expanded and continues to grow since they have kinds potential applications such as wavelength filtering, switching, coupling and multiplexing. One of resonators, coupled waveguides, ring resonators are designed and operated using various coupling configurations. Ring resonators can be particularly used as wavelength filter if the wavelength can fit a whole multiple time in the circumference of the ring. This article proposes to investigate the transmission spectra from the power source and amplify it in linearized ring resonator configurations and varies the input amplitude on five different wavelengths. With finite difference time domain method, the geometry and power source are simulated to obtain the better result and configuration. The results show the intensity phenomena of filtering in optical circuit.
Performance Investigation and Enhancement of Fiber Bragg Gratingfor Efficient...IOSRJECE
In this paper, the performance of various windowfunctions for Fiber Bragg Grating Sensor (FBGS)is investigated and evaluated in order to get optimized reflection spectrum with high reflectivity and an efficient side lobe suppression for efficient sensing measurement applications.For this purpose, a wide range of design parameters which include grating length and refractive index modulation amplitudehas been chosen to evaluate the sensor design. The performances of the different windowfunctions have been then compared in terms of reflectivity, full width half maximum bandwidth (FWHM), and sidelobe level(SLL) so as to get the most suitable design parametersto be used for sensing measurement.The simulation results presented in this paper show the effectiveness of the optimizedFBG sensor, which can be further implemented for high performance sensing applications.
Time Domain Modelling of Optical Add-drop filter based on Microcavity Ring Re...iosrjce
IOSR Journal of Electronics and Communication Engineering(IOSR-JECE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electronics and communication engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electronics and communication engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
A New Approach for Solving Inverse Scattering Problems with Overset Grid Gene...TELKOMNIKA JOURNAL
This paper presents a new approach of Forward-Backward Time-Stepping (FBTS)
utilizing Finite-Difference Time-Domain (FDTD) method with Overset Grid Generation (OGG)
method to solve the inverse scattering problems for electromagnetic (EM) waves. The proposed
FDTD method is combined with OGG method to reduce the geometrically complex problem to a
simple set of grids. The grids can be modified easily without the need to regenerate the grid
system, thus, it provide an efficient approach to integrate with the FBTS technique. Here, the
characteristics of the EM waves are analyzed. For the research mentioned in this paper, the
‘measured’ signals are syntactic data generated by FDTD simulations. While the ‘simulated’
signals are the calculated data. The accuracy of the proposed approach is validated. Good
agreements are obtained between simulation data and measured data. The proposed approach
has the potential to provide useful quantitative information of the unknown object particularly for
shape reconstruction, object detection and others.
Design of v slotted microstrip patch antenna for yielding improved gain bandw...eSAT Publishing House
This document describes the design of a V-slotted microstrip patch antenna to improve gain and bandwidth. The antenna was designed to operate at 5.9 GHz for WLAN and Wi-Max applications. It uses a single layer substrate with dielectric constant of 2.2. Three V-slots were cut into the rectangular patch to reduce the size while maintaining performance. Simulation results showed the antenna achieved a maximum bandwidth of 1.04 GHz and gain of 6.22 dBi. The V-slotted design improved the gain-bandwidth product over a basic rectangular patch antenna.
Design of v slotted microstrip patch antenna for yielding improved gain bandw...eSAT Journals
Abstract In this paper, a novel antenna design for improvement of patch antenna gain and bandwidth has been proposed.The proposed antenna design is a V-slotted rectangular microstrip patch antenna for yielding improved gain bandwidth product suitable for WLAN and Wi-Max applications. The antenna operates at 5.9 GHz and has the maximum achievable bandwidth obtained about 1.04Ghz and gain of 6.22dBi .The microstrip patch is constructed using a single layer RT/duroid (5880) substrate, having dielectric constant εr = 2.2 and loss tangent tan δ =0.001.A co-axial feed is used and the antenna is simulated using IE3D software from Zeland based on method of moments. Key Words: RMSA, V-slot, Gain-Bandwidth product, WLAN, Wi-Fi
METAMATERIAL STRUCTURE FOR BANDWIDTH IMPROVEMENT Sayahnarahul
The document describes the design of a rectangular microstrip patch antenna operating at 1.881 GHz that uses a split rectangular shaped metamaterial structure to improve bandwidth. The metamaterial structure is designed on an FR-4 substrate and loaded onto the patch antenna. This is expected to increase the antenna's bandwidth to 22.5 MHz while reducing the return loss to -18.175 dB, compared to 4.9 MHz bandwidth and -10.068 dB return loss without the metamaterial. The metamaterial takes advantage of negative permeability to enhance the antenna performance.
Analysis and Design of S-shaped Microstrip Patch AntennaIOSR Journals
Abstract: This paper gives a compact analysis and design of S-shaped Microstrip patch antenna which is best suited for Wi-max application. The analysis and design is simulated over IE3D software Ver. 15.2. We have taken a definite ground plane of 50x70 mm and patch size of 30x50 mm.The substrate thickness is taken as 1.6 mm and dielectric constant of 4.2 and loss tangent of 0.0013. The simulated result shows that the bandwidth is obtained in triple band- 7.79% at 0.262921 GHz band, 13.45% at 1.53034 GHz band and 28.0056% at 2.2382 GHz band. The obtained gain is 3.96 dBi at 2.33945 GHz. The obtained gain and bandwidth is best suited for Wi-max application. Keywords: S shape, Ground plane, Patch Antenna, Triple Band.
Mutual Coupling Reduction between Asymmetric Reflectarray Resonant Elements IJECEIAES
A physically asymmetric reflectarray element has been proposed for wide band operations. The dual resonant response has been introduced by tilting one side of the square path element. The numerical results have been analyzed in the frequency band between 24GHz to 28GHz where a reflection phase range of more than 600° has been achieved. The proposed asymmetric element can produce mutual coupling with adjacent elements on a reflectarray. This effect has been monitored by placing the elements in a mirror configuration on the surface of reflectarray. The single unit cell element results have been compared with conventional 4 element unit cell and proposed mirroring element configuration. The proposed mirroring element technique can be used to design a broadband reflectarray for high gain applications.
Modified Sierpinski Gasket for Wi-Fi and WLAN ApplicationsIJERA Editor
This document describes the design and simulation of a modified Sierpinski gasket fractal antenna for Wi-Fi and WLAN applications. Fractal antennas can provide multiband operation and miniaturization. The designed antenna uses a Sierpinski gasket fractal placed on an Arlon substrate with a line feed. Simulations show the antenna operates in the frequency ranges of 1.75-2.65 GHz and 5.7-7.65 GHz, covering Wi-Fi and WLAN bands. Return loss is below -15 dB and radiation patterns indicate good gain within the operating bands, confirming multiband performance for wireless applications. The fractal design approach allows for a small, low profile antenna suitable for integrated systems
NOVEL METHODOLOGY OF THE ULTRA SONIC BEAM IN LINEAR ARRAY TRANSDUCER FOR HIGH...Journal For Research
In this paper, the focusing of ultrasound beam is considered. Electronic circuitry is considered as support to the theme of the work. The results presented in this paper are notable for improved resolution. The extension of the application diversity is also proposed based on use of Piezo electric transceducers.
Design of a dual-band antenna for energy harvesting applicationjournalBEEI
This report presents an investigation on how to improve the current dual-band antenna to enhance the better result of the antenna parameters for energy harvesting application. Besides that, to develop a new design and validate the antenna frequencies that will operate at 2.4 GHz and 5.4 GHz. At 5.4 GHz, more data can be transmitted compare to 2.4 GHz. However, 2.4 GHz has long distance of radiation, so it can be used when far away from the antenna module compare to 5 GHz that has short distance in radiation. The development of this project includes the scope of designing and testing of antenna using computer simulation technology (CST) 2018 software and vector network analyzer (VNA) equipment. In the process of designing, fundamental parameters of antenna are being measured and validated, in purpose to identify the better antenna performance.
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1) The document is a seminar report submitted by Abhimithra Reddy to partially fulfill requirements for a Bachelor of Technology degree in Electronics and Communication Engineering.
2) The report discusses the art of invisible cloaking and was created under the guidance of Ms. Y. Jalajakshi.
3) The report was submitted to the Holy Mary Institute of Technology and Science in India in partial fulfillment of degree requirements from Jawaharlal Nehru Technological University Hyderabad.
This document discusses the concept of invisibility and metamaterials. It contains 5 chapters that cover: 1) an introduction to light and optics concepts like reflection and refraction, 2) the evolution and workings of metamaterials which exhibit negative refraction, 3) how metamaterials are formed, 4) limitations of metamaterials and cloaking, and 5) applications and future prospects of invisibility including cloaking. The abstract outlines how metamaterials can be used to alter light properties to achieve invisibility cloaking. The document also includes acknowledgements, a list of figures, and references.
The document discusses the concepts of invisible cloaking through the use of metamaterials. It begins with background on light and its properties like reflection and refraction. It then discusses how metamaterials evolved and how they were used in 2006 to create a simplified cloaking device at Duke University that could make objects invisible to microwaves. The device used concentric rings of metamaterials that caused microwaves to flow around a hidden object. Finally, it discusses how metamaterials are formed through the diffusion of hydrogen in metal-doped glasses, which leads to the growth of metallic nanoparticles that can self-arrange into quasi-periodic layered structures.
The document summarizes a project on developing an ASIP synthesis methodology called ASSIST between IIT Delhi and the University of Dortmund. The objectives were to combine strengths in synthesis and VLSI design from IIT Delhi and code generation and architecture from Dortmund. Work done included evaluating register file size, register windows, and cache vs scratchpad memory. A Leon processor was also synthesized for different configurations to generate an area/clock period database. Future work proposed further case studies and FPGA implementation to validate the methodology.
Radar absorber material (RAM) or microwave absorbers are designed to absorb electromagnetic radiation and are lined in anechoic chambers. They are made of fireproofed urethane foam loaded with carbon and cut into pyramid shapes of varying sizes. The pyramidal structure provides geometric matching to absorb incident radio frequencies. RAM absorbers are temperature resistant, fire retardant, and can withstand high power levels for long-term use in anechoic chambers to measure antenna patterns and create electromagnetic quiet zones.
Metamaterials are artificial materials engineered to have properties not found in nature. They are composed of periodic microscopic structures that interact with electromagnetic waves in ways that allow properties like a negative index of refraction. This presentation outlines metamaterials, how they achieve unusual properties, their timeline of development, applications like cloaking and terahertz devices, and remaining challenges in fabricating optical metamaterials.
This document summarizes a research paper on job satisfaction and attrition among school psychologists. It provides an abstract that outlines the paper's purpose, which is to examine personal and professional factors related to remaining in the profession of school psychology. It then presents a table of contents that lists 4 chapters, including an introduction discussing attrition and employment statistics, a literature review on attrition, personal characteristics, and environmental factors, a summary and discussion section, and a references page.
Cloaking making visible things into invisiblePraDeep Reddy
This document discusses invisibility cloaking technology. It defines cloaking as making visible things invisible using either metamaterials or an invisibility cloak system. There are two types of invisibility cloaking: 1) Using metamaterials to control light reflection properties to make objects invisible, and 2) An invisibility cloak system using a video camera, computer processor, and image projector to project background images to visually replace invisible stationary objects. Potential applications include cloaking military vehicles, making buildings invisible, and improving wireless signals by allowing waves to flow around objects.
The document describes a new microwave life detection system that can locate human victims trapped under earthquake rubble. The system works by sending microwave beams through rubble at L-band frequency, which can penetrate deeper than other frequencies. Any signals reflected from a trapped victim's breathing and heartbeat movements would be detected. A clutter cancellation system filters out fixed reflections from rubble while preserving modulated signals from living beings. The system could help reduce loss of life from earthquakes by remotely detecting trapped humans within seconds.
Comparative Study of Evolutionary Algorithms for the Optimum Design Of Thin B...jmicro
With the increasing levels of Electromagnetic pollution almost exponentially in this modern age of
Electronics reported and highlighted by numerous studies carried out by scientists from all over the world,
inspire engineers to concentrate their research for the optimum design of multilayer microwave absorber
considering various parameters which are inherently conflicting in nature. In this paper we mainly focus
on the comparative study of different Evolutionary algorithms for the optimum design of thin broadband (2-
20GHz) multilayer microwave absorber for oblique incidence (300
) considering arbitrary polarization of
the electromagnetic waves. Different models are presented and synthesized using various Evolutionary
algorithm namely Firefly algorithm (FA), Particle swarm optimization (PSO), Artificial bee colony
optimization (ABC) and the best simulated results are tabulated and compared with each others.
Improving the performance parameters of microstrip patch antenna by using ebg...eSAT Journals
Abstract Antibiotic toxicity and multi drug resistant pathogens are the two greatest challenges being faced by today's medical world. In the present study, the antimicrobial activity of spices has been investigated as an alternative to antibiotics in order to tackle these dangers. In search of bioactive compound, methanol and acetone extract of 5 Indian spices were screened for antibacterial property. The choice of spice as an alternative is based on two basic reasons: firstly, plants have been the model source of medicine since ancient times and secondly, the increasing acceptance of herbal medicines by general population methanolic and acetone extracts were used to determine antifungal properties of the spices. The antifungal activity of five common Indian spices namely clove, ajwain, turmeric, dalchini and black pepper against two bacteria Aspergillus niger and Trichoderma sp. The results revealed that the methanol extracts of spices (MIC values of 20- 100 μl/ml) have high antimicrobial activities on all test organisms (range of inhibition, 6- 16 mm) as compare to acetone extracts of spices in same concentration. Results concluded that these spices contain high amount of secondary metabolites due to these metabolites they have high antimicrobial activity and it can be used as good bio- preservater and it can also use for medicinal purpose. Keywords: Antibacterial Properties, Secondary Metabolites, Multi Drug Resistant Pathogens.
This document summarizes research on improving the performance of microstrip patch antennas by using an electromagnetic bandgap (EBG) substrate. It describes how EBG structures can suppress surface waves in patch antennas to increase bandwidth, gain, and radiation efficiency. The document analyzes the design and simulation of a rectangular patch antenna surrounded by a cylindrical EBG structure consisting of metallic rings and vias. Simulation results show the EBG substrate increases bandwidth to over 10% and boosts gain from 6dB to 7.7dB compared to a standard patch antenna.
Microwave Planar Sensor for Determination of the Permittivity of Dielectric M...journalBEEI
This paper proposed a single port rectangular microwave resonator sensor. This sensor operates at the resonance frequency of 4GHz. The sensor consists of micro-strip transmission line and applied the enhancement method. The enhancement method is able to improve the return loss of the sensor, respectively. Plus, the proposed sensor is designed and fabricated on Roger 5880 substrate. Based on the results, the percentage of error for the proposed rectangular sensor is 0.2% to 8%. The Q-factor of the sensor is 174.
Variable radiation pattern from co axial probe fed rectangular patch antenna ...eSAT Journals
Abstract The idea of obtaining variable radiation patterns from the same antenna is important aspect in achieving the adaptive antenna systems. In the EM signal processing the change of radiation signifies the information to be transmitted, its rate of transmission, the geographical changes and direction to transmit etc. i.e. each time when the requirement arises to change the radiation pattern it has to be done to satisfy the conditions. Electronically steerable antennas were used where the antenna radiation will be altered by varying the feed and similar case is applied for shaped patterns from array antenna where the feed to be given will be calculated and given accordingly. In the present concept the metamaterials are used to obtain different radiation patterns occurred at different operating frequencies using the same antenna without changing the antenna physically are varying its feed. Key Words: Inductance, capacitance, operating frequency, variable radiation, enhancement, radiation cancellation.
This document summarizes the time domain modeling of an optical add-drop filter based on microcavity ring resonators. It uses the Multiresolution Time Domain (MRTD) technique to analyze the transmission characteristics of single and double ring configurations. The MRTD method provides high numerical accuracy while reducing computational burden compared to FDTD. The analysis investigates parameters like gap size, distance between rings, and ring/waveguide width to understand their effects on transmitted power and quality factors. Studies of a 3.4 μm diameter ring show quality factors of several thousand and a free spectral range of 9 THz can be achieved in the 1.55 μm wavelength range.
Design & simulation of dual band t shaped slot micro strip antenna for c-...eSAT Journals
This document describes the design and simulation of a dual band T-shaped microstrip patch antenna for C-band applications between 5.4GHz and 6.6GHz. The antenna was designed on an FR4 substrate using HFSS simulation software. Key results include return losses below -26dB, a voltage standing wave ratio below 1.2, gains between 2.7-4.8dB depending on frequency and substrate thickness, radiation efficiencies between 37-71%, and half power beamwidths of 60 degrees. The document analyzes the antenna performance parameters and field distributions at different operating frequencies and substrate thicknesses.
In this paper we are interested to calculate the resonant frequency of rectangular patch antenna using artificial neural networks based on the multilayered perceptrons. The artificial neural networks built, transforms the inputs which are, the width of the patch W, the length of the patch L, the thickness of the substrate h and the dielectric permittivity ε_r to the resonant frequency fr which is an important parameter to design a microstrip patch antenna.The proposed method based on artificial neural networks is compared to some analytical methods using some statistical criteria. The obtained results demonstrate that artificial neural networks are more adequate to achieve the purpose than the other methods and present a good argument with the experimental results available in the literature. Hence, the artificial neural networks can be used by researchers to predict the resonant frequency of a rectangular patch antenna knowing length (L), width (W), thickness (h) and dielectric permittivity 〖(ε〗_r) with a good accuracy.
Simulation and analysis of slot coupled patch antennaiaemedu
The document discusses the simulation and analysis of a slot-coupled patch antenna at different frequencies using HFSS software. It describes the structure of the antenna, which consists of a rectangular patch separated from the ground plane by an air gap and dielectric material. The paper simulates the antenna at 2.25 GHz, 3.25 GHz, and 4.5 GHz. It analyzes the return loss and radiation patterns at each frequency. The results show that bandwidth increases at higher frequencies but radiation patterns degrade, indicating a tradeoff between bandwidth and frequency of operation.
Simulation and analysis of slot coupled patch antennaiaemedu
The document summarizes research on simulating and analyzing a slot-coupled patch antenna at different frequencies using HFSS software. It describes the structure of the antenna, which consists of a rectangular patch separated from the ground plane by an air gap and dielectric material. The antenna is fed by two slots on the ground plane. Simulation results showed that bandwidth increases at higher frequencies but radiation patterns deteriorate. There is thus a tradeoff between operating frequency, bandwidth, and radiation efficiency. The design was able to achieve bandwidth increases up to 80 MHz at 4.5 GHz but radiation patterns worsened compared to lower frequencies.
Mimo and cooperative mimo comparison in energy constrained wireless sensor ne...eSAT Journals
Abstract In Wireless Sensor Network commonly referred as WSN, the hubs or nodes are operated by batteries so that the energy utilization should be diminished, while fulfilling the given throughput and given requirement. The paper studies about the performance and energy consumption of cooperative MIMO and MIMO (multi input multi output) based communication. The average energy usage comprises circuit energy and transmission energy consumption. The comparison between the multi-input- multi-output (MIMO) and cooperative MIMO techniques help us to choose the best scheme for energy constrained wireless sensor network application. The simulation result shows that energy efficiency of MIMO (multi-input-multi-output) and SISO (single-input-single-output) is better for longer distances and thud increase the system life time. Keywords: Cooperative MIMO, MISO, SISO, SIMO, wireless sensor network, energy efficiency, BER performance
Reconfigurable Metamaterial Structure at Millimeter Wave Frequency Range IJECEIAES
In this paper, reconfigurable metamaterial structure at millimeter wave frequency range was designed and simulated for a future fifth generation (5G) mobile-phone beam switching applications. The new proposed structure was composed of a bridge-shaped resonator (BSR) in the front face and strip line at the back face of the unit cell which operates at 28GHz. First, nonreconfigurable low loss BSR unit cell was designed and subsequently, the reconfigurability was achieved using four switches formed in the gaps of the structure. The proposed structure achieves the lowest loss and almost full transmission among its counterparts by -0.06dB (0.99 in linear scale). To demonstrate the reconfigurability of the metamaterial, the reflection and transmission coefficients and real parts of the effective refractive index at each reconfigured frequency were studied and investigated. Simulation results showed that a high transmission and reflection peaks occur at each resonance frequency according to change the state of the switches.
Reduction of Mutual Coupling between Closely Spaced Microstrip Antennas Array...TELKOMNIKA JOURNAL
Reducing mutual coupling is a key research area in design of compact microstrip antennas
arrays. To minimize the overall size of the antennas arrays, the distance between them must be very
small, as a result a strong mutual coupling is appears. Periodic structures can help to design a low profile
of antennas arrays and enable to improve their performances by the suppression of surface waves
propagation in a given frequency range. This paper proposes a novel configuration of mushroom-like
electromagnetic band-gap (2D-EBG) structure created by microstrip technology placed between two
antennas arrays to reduce the mutual coupling more than -33.24dB. When 13×2 EBG structures are used,
the mutual coupling reduces to -59.36dB at the operation frequency 5.8GHz of the antennas arrays. A
26.12dB mutual coupling reduction is achieved, which proves that the surface wave is suppressed. The
proposed configuration is designed, optimized, and miniaturized by using electromagnetic software CST
Microwave Studio. The measured results show that there is a good agreement with the computed results.
1) The document describes the design of a broadband circular microstrip patch antenna with a plus slot for WLAN and WiMAX applications operating at 4.7 GHz.
2) The antenna was simulated using IE3D software and was found to have a bandwidth of 78.81% along with a maximum directivity of 6 dBi and maximum efficiency of 88%.
3) Key parameters of the antenna like return loss, radiation pattern, and efficiency were studied and optimized during the design process.
An ultra wideband antenna for Ku band applicationsIJECEIAES
This paper presents a candidate ultra wideband antenna for Ku-band wireless communi- cations applications, analyzed and optimized by the finite element method (FEM). This three-dimensional modeling was realized and compared with published antennas for val- idate the performances of the proposed antenna. Its design is based on the insertion o fseveral symmetrical slots of different sizes on the ground plane of a mono-layer patch antenna to overcome the main limitation of the narrow bandwidth of patch antennas. The proposed antenna, made on an FR-4 epoxy mono-layer substrate with a defected ground plane (dielectric constant εr = 4,4, loss tangent tan δ = 0,02 and thickness hs = 1.6 mm). The simulated numerical results obtained are very satisfying; Bandwidth = 10.48 GHz from f1 = 9.34 GHz to f2 = 19.82 GHz, S11 = -34.17 dB, Voltage Stationary Wave Ratio VSWR = 1.04 , Gain = 6.27 dB.
This document discusses the performance analysis of a microstrip printed antenna conformed on a cylindrical body operating at a resonance frequency of 4.6 GHz for the TM01 mode. It begins with an introduction to microstrip antennas and the effects of curvature. It then presents mathematical models for the electric and magnetic fields, input impedance, return loss, and voltage standing wave ratio for a curved microstrip antenna. Results show the resonance frequency shifts 35 MHz as the radius of curvature changes from 6 mm to a flat antenna. Graphs also show the real and imaginary parts of input impedance vary with frequency for different radii of curvature.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
ENERGY EFFICIENCY OF MIMO COOPERATIVE NETWORKS WITH ENERGY HARVESTING SENSOR ...ijasuc
This paper addresses the maximizing network lifetime problem in wireless sensor networks (WSNs) taking
into account the total Symbol Error rate (SER) at destination. Therefore, efficient power management is
needed for extend network lifetime. Our approach consists to provide the optimal transmission power
using the orthogonal multiple access channels between each sensor. In order to deeply study the
properties of our approach, firstly, the simple case is considered; the information sensed by the source
node passes by a single relay before reaching the destination node. Secondly, global case is studied; the
information passes by several relays. We consider, in the previous both cases, that the batteries are nonrechargeable. Thirdly, we spread our work the case where the batteries are rechargeable with unlimited
storage capacity. In all three cases, we suppose that Maximum Ratio Combining (MRC) is used as a
detector, and Amplify and Forward (AF) as a relaying strategy. Simulation results show the viability of
our approach which the network lifetime is extended of more than 70.72%when the batteries are non
rechargeable and 100.51% when the batteries are rechargeable in comparison with other traditional
method.
ENERGY EFFICIENCY OF MIMO COOPERATIVE NETWORKS WITH ENERGY HARVESTING SENSOR ...ijasuc
This paper addresses the maximizing network lifetime problem in wireless sensor networks (WSNs) taking
into account the total Symbol Error rate (SER) at destination. Therefore, efficient power management is
needed for extend network lifetime. Our approach consists to provide the optimal transmission power
using the orthogonal multiple access channels between each sensor. In order to deeply study the
properties of our approach, firstly, the simple case is considered; the information sensed by the source
node passes by a single relay before reaching the destination node. Secondly, global case is studied; the
information passes by several relays. We consider, in the previous both cases, that the batteries are nonrechargeable. Thirdly, we spread our work the case where the batteries are rechargeable with unlimited
storage capacity. In all three cases, we suppose that Maximum Ratio Combining (MRC) is used as a
detector, and Amplify and Forward (AF) as a relaying strategy. Simulation results show the viability of
our approach which the network lifetime is extended of more than 70.72%when the batteries are non
rechargeable and 100.51% when the batteries are rechargeable in comparison with other traditional
method.
A PROXIMITY FEED DUAL BAND CIRCULAR SHAPED ANTENNA WITH SEMICIRCULAR GROUND P...Amitesh Raikwar
In this work, we present a Circular Shaped proximity feed
Microstrip Patch Antenna. The antenna is comprised of circular
shaped radiation patch and this radiating patch is faded
by proximity coupling. The ground plane of the antenna has
Semicircular pattern to improve the coupling level of the
patch. The simulated result shows it provides the return loss
less than -10 dB for two frequencies 1.27 GHz and 1.43 GHz
which could be a useful frequencies for wireless communication
system. The simulation work is carried out on IE3D
software, a product of Zeland Software Company.
Similar to Evolutionary algorithms for optimum design of thin broadband multilayer microwave absorber (20)
Mechanical properties of hybrid fiber reinforced concrete for pavementseSAT Journals
Abstract
The effect of addition of mono fibers and hybrid fibers on the mechanical properties of concrete mixture is studied in the present
investigation. Steel fibers of 1% and polypropylene fibers 0.036% were added individually to the concrete mixture as mono fibers and
then they were added together to form a hybrid fiber reinforced concrete. Mechanical properties such as compressive, split tensile and
flexural strength were determined. The results show that hybrid fibers improve the compressive strength marginally as compared to
mono fibers. Whereas, hybridization improves split tensile strength and flexural strength noticeably.
Keywords:-Hybridization, mono fibers, steel fiber, polypropylene fiber, Improvement in mechanical properties.
Material management in construction – a case studyeSAT Journals
Abstract
The objective of the present study is to understand about all the problems occurring in the company because of improper application
of material management. In construction project operation, often there is a project cost variance in terms of the material, equipments,
manpower, subcontractor, overhead cost, and general condition. Material is the main component in construction projects. Therefore,
if the material management is not properly managed it will create a project cost variance. Project cost can be controlled by taking
corrective actions towards the cost variance. Therefore a methodology is used to diagnose and evaluate the procurement process
involved in material management and launch a continuous improvement was developed and applied. A thorough study was carried
out along with study of cases, surveys and interviews to professionals involved in this area. As a result, a methodology for diagnosis
and improvement was proposed and tested in selected projects. The results obtained show that the main problem of procurement is
related to schedule delays and lack of specified quality for the project. To prevent this situation it is often necessary to dedicate
important resources like money, personnel, time, etc. To monitor and control the process. A great potential for improvement was
detected if state of the art technologies such as, electronic mail, electronic data interchange (EDI), and analysis were applied to the
procurement process. These helped to eliminate the root causes for many types of problems that were detected.
Managing drought short term strategies in semi arid regions a case studyeSAT Journals
Abstract
Drought management needs multidisciplinary action. Interdisciplinary efforts among the experts in various fields of the droughts
prone areas are helpful to achieve tangible and permanent solution for this recurring problem. The Gulbarga district having the total
area around 16, 240 sq.km, and accounts 8.45 per cent of the Karnataka state area. The district has been situated with latitude 17º 19'
60" North and longitude of 76 º 49' 60" east. The district is situated entirely on the Deccan plateau positioned at a height of 300 to
750 m above MSL. Sub-tropical, semi-arid type is one among the drought prone districts of Karnataka State. The drought
management is very important for a district like Gulbarga. In this paper various short term strategies are discussed to mitigate the
drought condition in the district.
Keywords: Drought, South-West monsoon, Semi-Arid, Rainfall, Strategies etc.
Life cycle cost analysis of overlay for an urban road in bangaloreeSAT Journals
Abstract
Pavements are subjected to severe condition of stresses and weathering effects from the day they are constructed and opened to traffic
mainly due to its fatigue behavior and environmental effects. Therefore, pavement rehabilitation is one of the most important
components of entire road systems. This paper highlights the design of concrete pavement with added mono fibers like polypropylene,
steel and hybrid fibres for a widened portion of existing concrete pavement and various overlay alternatives for an existing
bituminous pavement in an urban road in Bangalore. Along with this, Life cycle cost analyses at these sections are done by Net
Present Value (NPV) method to identify the most feasible option. The results show that though the initial cost of construction of
concrete overlay is high, over a period of time it prove to be better than the bituminous overlay considering the whole life cycle cost.
The economic analysis also indicates that, out of the three fibre options, hybrid reinforced concrete would be economical without
compromising the performance of the pavement.
Keywords: - Fatigue, Life cycle cost analysis, Net Present Value method, Overlay, Rehabilitation
Laboratory studies of dense bituminous mixes ii with reclaimed asphalt materialseSAT Journals
Abstract
The issue of growing demand on our nation’s roadways over that past couple of decades, decreasing budgetary funds, and the need to
provide a safe, efficient, and cost effective roadway system has led to a dramatic increase in the need to rehabilitate our existing
pavements and the issue of building sustainable road infrastructure in India. With these emergency of the mentioned needs and this
are today’s burning issue and has become the purpose of the study.
In the present study, the samples of existing bituminous layer materials were collected from NH-48(Devahalli to Hassan) site.The
mixtures were designed by Marshall Method as per Asphalt institute (MS-II) at 20% and 30% Reclaimed Asphalt Pavement (RAP).
RAP material was blended with virgin aggregate such that all specimens tested for the, Dense Bituminous Macadam-II (DBM-II)
gradation as per Ministry of Roads, Transport, and Highways (MoRT&H) and cost analysis were carried out to know the economics.
Laboratory results and analysis showed the use of recycled materials showed significant variability in Marshall Stability, and the
variability increased with the increase in RAP content. The saving can be realized from utilization of recycled materials as per the
methodology, the reduction in the total cost is 19%, 30%, comparing with the virgin mixes.
Keywords: Reclaimed Asphalt Pavement, Marshall Stability, MS-II, Dense Bituminous Macadam-II
Laboratory investigation of expansive soil stabilized with natural inorganic ...eSAT Journals
This document summarizes a study on stabilizing expansive black cotton soil with the natural inorganic stabilizer RBI-81. Laboratory tests were conducted to evaluate the effect of RBI-81 on the soil's engineering properties. The tests showed that with 2% RBI-81 and 28 days of curing, the unconfined compressive strength increased by around 250% and the CBR value improved by approximately 400% compared to the untreated soil. Overall, the study found that RBI-81 effectively improved the strength properties of the black cotton soil and its suitability as a soil stabilizer was supported.
Influence of reinforcement on the behavior of hollow concrete block masonry p...eSAT Journals
Abstract
Reinforced masonry was developed to exploit the strength potential of masonry and to solve its lack of tensile strength. Experimental
and analytical studies have been carried out to investigate the effect of reinforcement on the behavior of hollow concrete block
masonry prisms under compression and to predict ultimate failure compressive strength. In the numerical program, three dimensional
non-linear finite elements (FE) model based on the micro-modeling approach is developed for both unreinforced and reinforced
masonry prisms using ANSYS (14.5). The proposed FE model uses multi-linear stress-strain relationships to model the non-linear
behavior of hollow concrete block, mortar, and grout. Willam-Warnke’s five parameter failure theory has been adopted to model the
failure of masonry materials. The comparison of the numerical and experimental results indicates that the FE models can successfully
capture the highly nonlinear behavior of the physical specimens and accurately predict their strength and failure mechanisms.
Keywords: Structural masonry, Hollow concrete block prism, grout, Compression failure, Finite element method,
Numerical modeling.
Influence of compaction energy on soil stabilized with chemical stabilizereSAT Journals
This document summarizes a study on the influence of compaction energy on soil stabilized with a chemical stabilizer. Laboratory tests were conducted on locally available loamy soil treated with a patented polymer liquid stabilizer and compacted at four different energy levels. The study found that increasing the compaction effort increased the density of both untreated and treated soil, but the rate of increase was lower for stabilized soil. Treating the soil with the stabilizer improved its unconfined compressive strength and resilient modulus, and reduced accumulated plastic strain, with these properties further improved by higher compaction efforts. The stabilized soil exhibited strength and performance benefits compared to the untreated soil.
Geographical information system (gis) for water resources managementeSAT Journals
This document describes a hydrological framework developed in the form of a Hydrologic Information System (HIS) to meet the information needs of various government departments related to water management in a state. The HIS consists of a hydrological database coupled with tools for collecting and analyzing spatial and non-spatial water resources data. It also incorporates a hydrological model to indirectly assess water balance components over space and time. A web-based GIS portal was created to allow users to access and visualize the hydrological data, as well as outputs from the SWAT hydrological model. The framework is intended to facilitate integrated water resources planning and management across different administrative levels.
Forest type mapping of bidar forest division, karnataka using geoinformatics ...eSAT Journals
Abstract
The study demonstrate the potentiality of satellite remote sensing technique for the generation of baseline information on forest types
including tree plantation details in Bidar forest division, Karnataka covering an area of 5814.60Sq.Kms. The Total Area of Bidar
forest division is 5814Sq.Kms analysis of the satellite data in the study area reveals that about 84% of the total area is Covered by
crop land, 1.778% of the area is covered by dry deciduous forest, 1.38 % of mixed plantation, which is very threatening to the
environmental stability of the forest, future plantation site has been mapped. With the use of latest Geo-informatics technology proper
and exact condition of the trees can be observed and necessary precautions can be taken for future plantation works in an appropriate
manner
Keywords:-RS, GIS, GPS, Forest Type, Tree Plantation
Factors influencing compressive strength of geopolymer concreteeSAT Journals
Abstract
To study effects of several factors on the properties of fly ash based geopolymer concrete on the compressive strength and also the
cost comparison with the normal concrete. The test variables were molarities of sodium hydroxide(NaOH) 8M,14M and 16M, ratio of
NaOH to sodium silicate (Na2SiO3) 1, 1.5, 2 and 2.5, alkaline liquid to fly ash ratio 0.35 and 0.40 and replacement of water in
Na2SiO3 solution by 10%, 20% and 30% were used in the present study. The test results indicated that the highest compressive
strength 54 MPa was observed for 16M of NaOH, ratio of NaOH to Na2SiO3 2.5 and alkaline liquid to fly ash ratio of 0.35. Lowest
compressive strength of 27 MPa was observed for 8M of NaOH, ratio of NaOH to Na2SiO3 is 1 and alkaline liquid to fly ash ratio of
0.40. Alkaline liquid to fly ash ratio of 0.35, water replacement of 10% and 30% for 8 and 16 molarity of NaOH and has resulted in
compressive strength of 36 MPa and 20 MPa respectively. Superplasticiser dosage of 2 % by weight of fly ash has given higher
strength in all cases.
Keywords: compressive strength, alkaline liquid, fly ash
Experimental investigation on circular hollow steel columns in filled with li...eSAT Journals
Abstract
Composite Circular hollow Steel tubes with and without GFRP infill for three different grades of Light weight concrete are tested for
ultimate load capacity and axial shortening , under Cyclic loading. Steel tubes are compared for different lengths, cross sections and
thickness. Specimens were tested separately after adopting Taguchi’s L9 (Latin Squares) Orthogonal array in order to save the initial
experimental cost on number of specimens and experimental duration. Analysis was carried out using ANN (Artificial Neural
Network) technique with the assistance of Mini Tab- a statistical soft tool. Comparison for predicted, experimental & ANN output is
obtained from linear regression plots. From this research study, it can be concluded that *Cross sectional area of steel tube has most
significant effect on ultimate load carrying capacity, *as length of steel tube increased- load carrying capacity decreased & *ANN
modeling predicted acceptable results. Thus ANN tool can be utilized for predicting ultimate load carrying capacity for composite
columns.
Keywords: Light weight concrete, GFRP, Artificial Neural Network, Linear Regression, Back propagation, orthogonal
Array, Latin Squares
Experimental behavior of circular hsscfrc filled steel tubular columns under ...eSAT Journals
This document summarizes an experimental study that tested circular concrete-filled steel tube columns with varying parameters. 45 specimens were tested with different fiber percentages (0-2%), tube diameter-to-wall-thickness ratios (D/t from 15-25), and length-to-diameter (L/d) ratios (from 2.97-7.04). The results found that columns filled with fiber-reinforced concrete exhibited higher stiffness, equal ductility, and enhanced energy absorption compared to those filled with plain concrete. The load carrying capacity increased with fiber content up to 1.5% but not at 2.0%. The analytical predictions of failure load closely matched the experimental values.
Evaluation of punching shear in flat slabseSAT Journals
Abstract
Flat-slab construction has been widely used in construction today because of many advantages that it offers. The basic philosophy in
the design of flat slab is to consider only gravity forces; this method ignores the effect of punching shear due to unbalanced moments
at the slab column junction which is critical. An attempt has been made to generate generalized design sheets which accounts both
punching shear due to gravity loads and unbalanced moments for cases (a) interior column; (b) edge column (bending perpendicular
to shorter edge); (c) edge column (bending parallel to shorter edge); (d) corner column. These design sheets are prepared as per
codal provisions of IS 456-2000. These design sheets will be helpful in calculating the shear reinforcement to be provided at the
critical section which is ignored in many design offices. Apart from its usefulness in evaluating punching shear and the necessary
shear reinforcement, the design sheets developed will enable the designer to fix the depth of flat slab during the initial phase of the
design.
Keywords: Flat slabs, punching shear, unbalanced moment.
Evaluation of performance of intake tower dam for recent earthquake in indiaeSAT Journals
Abstract
Intake towers are typically tall, hollow, reinforced concrete structures and form entrance to reservoir outlet works. A parametric
study on dynamic behavior of circular cylindrical towers can be carried out to study the effect of depth of submergence, wall thickness
and slenderness ratio, and also effect on tower considering dynamic analysis for time history function of different soil condition and
by Goyal and Chopra accounting interaction effects of added hydrodynamic mass of surrounding and inside water in intake tower of
dam
Key words: Hydrodynamic mass, Depth of submergence, Reservoir, Time history analysis,
Evaluation of operational efficiency of urban road network using travel time ...eSAT Journals
This document evaluates the operational efficiency of an urban road network in Tiruchirappalli, India using travel time reliability measures. Traffic volume and travel times were collected using video data from 8-10 AM on various roads. Average travel times, 95th percentile travel times, and buffer time indexes were calculated to assess reliability. Non-motorized vehicles were found to most impact reliability on one road. A relationship between buffer time index and traffic volume was developed. Finally, a travel time model was created and validated based on length, speed, and volume.
Estimation of surface runoff in nallur amanikere watershed using scs cn methodeSAT Journals
Abstract
The development of watershed aims at productive utilization of all the available natural resources in the entire area extending from
ridge line to stream outlet. The per capita availability of land for cultivation has been decreasing over the years. Therefore, water and
the related land resources must be developed, utilized and managed in an integrated and comprehensive manner. Remote sensing and
GIS techniques are being increasingly used for planning, management and development of natural resources. The study area, Nallur
Amanikere watershed geographically lies between 110 38’ and 110 52’ N latitude and 760 30’ and 760 50’ E longitude with an area of
415.68 Sq. km. The thematic layers such as land use/land cover and soil maps were derived from remotely sensed data and overlayed
through ArcGIS software to assign the curve number on polygon wise. The daily rainfall data of six rain gauge stations in and around
the watershed (2001-2011) was used to estimate the daily runoff from the watershed using Soil Conservation Service - Curve Number
(SCS-CN) method. The runoff estimated from the SCS-CN model was then used to know the variation of runoff potential with different
land use/land cover and with different soil conditions.
Keywords: Watershed, Nallur watershed, Surface runoff, Rainfall-Runoff, SCS-CN, Remote Sensing, GIS.
Estimation of morphometric parameters and runoff using rs & gis techniqueseSAT Journals
This document summarizes a study that used remote sensing and GIS techniques to estimate morphometric parameters and runoff for the Yagachi catchment area in India over a 10-year period. Morphometric analysis was conducted to understand the hydrological response at the micro-watershed level. Daily runoff was estimated using the SCS curve number model. The results showed a positive correlation between rainfall and runoff. Land use/land cover changes between 2001-2010 were found to impact estimated runoff amounts. Remote sensing approaches provided an effective means to model runoff for this large, ungauged area.
Effect of variation of plastic hinge length on the results of non linear anal...eSAT Journals
Abstract The nonlinear Static procedure also well known as pushover analysis is method where in monotonically increasing loads are applied to the structure till the structure is unable to resist any further load. It is a popular tool for seismic performance evaluation of existing and new structures. In literature lot of research has been carried out on conventional pushover analysis and after knowing deficiency efforts have been made to improve it. But actual test results to verify the analytically obtained pushover results are rarely available. It has been found that some amount of variation is always expected to exist in seismic demand prediction of pushover analysis. Initial study is carried out by considering user defined hinge properties and default hinge length. Attempt is being made to assess the variation of pushover analysis results by considering user defined hinge properties and various hinge length formulations available in literature and results compared with experimentally obtained results based on test carried out on a G+2 storied RCC framed structure. For the present study two geometric models viz bare frame and rigid frame model is considered and it is found that the results of pushover analysis are very sensitive to geometric model and hinge length adopted. Keywords: Pushover analysis, Base shear, Displacement, hinge length, moment curvature analysis
Effect of use of recycled materials on indirect tensile strength of asphalt c...eSAT Journals
Abstract
Depletion of natural resources and aggregate quarries for the road construction is a serious problem to procure materials. Hence
recycling or reuse of material is beneficial. On emphasizing development in sustainable construction in the present era, recycling of
asphalt pavements is one of the effective and proven rehabilitation processes. For the laboratory investigations reclaimed asphalt
pavement (RAP) from NH-4 and crumb rubber modified binder (CRMB-55) was used. Foundry waste was used as a replacement to
conventional filler. Laboratory tests were conducted on asphalt concrete mixes with 30, 40, 50, and 60 percent replacement with RAP.
These test results were compared with conventional mixes and asphalt concrete mixes with complete binder extracted RAP
aggregates. Mix design was carried out by Marshall Method. The Marshall Tests indicated highest stability values for asphalt
concrete (AC) mixes with 60% RAP. The optimum binder content (OBC) decreased with increased in RAP in AC mixes. The Indirect
Tensile Strength (ITS) for AC mixes with RAP also was found to be higher when compared to conventional AC mixes at 300C.
Keywords: Reclaimed asphalt pavement, Foundry waste, Recycling, Marshall Stability, Indirect tensile strength.
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELgerogepatton
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Understanding Inductive Bias in Machine LearningSUTEJAS
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Evolutionary algorithms for optimum design of thin broadband multilayer microwave absorber
1. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 04 Issue: 07 | July-2015, Available @ http://www.ijret.org 419
EVOLUTIONARY ALGORITHMS FOR OPTIMUM DESIGN OF THIN
BROADBAND MULTILAYER MICROWAVE ABSORBER
Jyotirmay Tewary1
, G. K. Mahanti2
, Kajla Basu3
1
Assistant Professor, Department of Electronics & Communication Engineering, Bengal college of Engineering &
Technology Durgapur, West Bengal, India
2
Professor, Department of Electronics & Communication Engineering, National Institute of Technology Durgapur,
West Bengal, India
3
Professor, Department of Mathematics, National Institute of Technology Durgapur, West Bengal, India
Abstract
In this paper we focused on the comparative study of three very popular and most recently developed nature inspired evolutionary
algorithms namely Biogeography based optimization algorithm (BBO), Flower pollination algorithm (FPA) and Artificial bee
colony optimization algorithm (ABC) for developing a model of 6 layers thin broadband (0.2-20GHz) microwave absorber. The
model is optimized for oblique wide angle of incidence (450
, 600
) taking both TE and TM polarization of the electromagnetic wave
under consideration. The primary goal of our design is to minimizing the overall reflection coefficient of the absorber and its total
thickness by selecting the proper layer of materials from a predefined database of existing materials. 8 different models are
presented and synthesize considering both these design consideration simultaneously and for only overall reflection coefficient of
the absorber while total thickness is not taken into consideration during optimization for each cases. The optimum values of all
the significant parameters of the multilayer absorber for different models have been compared and tabulated using BBO, FPA
and ABC algorithms which established the superiority of our proposed design.
Keywords: Multilayer microwave absorber, Oblique incidence, Broadband, Evolutionary algorithms, Arbitrary
polarization
--------------------------------------------------------------------***----------------------------------------------------------------------
1. INTRODUCTION
Microwave Absorbers in the RF/Microwave Engineering are
the material that is widely used to attenuate energy in an
Electromagnetic wave. This Absorber is capable to reduce
electromagnetic hazards or unwanted radiation that could
interfere with the system operation and may degrade the
performance of the system as well. To avoid this unwanted
or undesired interference instruments and other devices are
coated or protected by absorbing materials. This make the
multilayer microwave absorber finds its wide range of
application in almost all defense and civil electronics
industries like radar systems, satellite communication,
electromagnetic compatibility and many more. So with the
increasing applications of this microwave absorber in this
modern age of electronics inspire engineers to take this
problem of developing optimum design of multilayer
microwave absorber as a challenging task. While designing
the same we have to consider some fact which is inherently
conflicting in nature. The absorber must have minimum
reflecting coefficient of the electromagnetic wave in a
particular frequency band and incident angle for arbitrary
polarization of the electromagnetic wave as well as the
absorber should be thin and lightweight too. So there must
be a proper trade-offs between all these conflicting goals.
This can be achieve only by adjusting different parameters
of the multilayer structure of the microwave absorber such
as number of layers, permeability, permittivity, frequency
range, the angle of incidence, thickness of the individual
layers, types of material used and the wave polarization
using different optimization technique. Earlier some older
optimization algorithm like simplex method, simulated
annealing was implemented for the design of multilayer
microwave absorber but they finds their limitations to have a
large convergence time and a tendency to get trapped in
local optimization[13]. Hence more modified and
sophisticated evolutionary algorithm such as Genetic
algorithm (GA) [1-3, 6], Central force optimization (CFO)
[7], Differential evolution (DE) [8] and particle swarm
optimization (PSO) [4, 5, 14-22], have been applied more
successfully to the problem of design of multilayer
microwave absorber. In this paper a comparative study of
comparatively newly developed nature inspired optimization
algorithms such as Biogeography based optimization
algorithm (BBO) [23-25], Flower pollination algorithm
(FPA) [26]and Artificial bee colony optimization
algorithm(ABC)[27-28], have been successfully
implemented for the optimum design of 6 layers microwave
absorber. The absorber is optimized for oblique wide angle
of incidence ( 450
, 600
) in the wide frequency band(0.2-
20GHz) considering both TE and TM polarization of the
electromagnetic wave. While formulating the objective or
cost function we included the weighted form of the total
thickness along with the reflection coefficient to solve the
conflicting parameters of our design more significantly. A
brief overview for the remainder of this paper is as follows:
Section 2 gives the basic concept of multilayer structure of
the microwave absorber, section 3 explain the formulation
2. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 04 Issue: 07 | July-2015, Available @ http://www.ijret.org 420
of the cost function to be optimized using evolutionary
algorithms, the fundamental concept and theoretical
overview of BBO, FPA and ABC algorithms are described
in the section 4, the simulation results and significant
parameters of different models of the multilayer
microwave absorber of our design is presented in section 5
and finally the concluding arguments are explained in
section 6 respectively.
2. PHYSICAL ELECTROMAGNETIC MODEL
OF MULTILAYER MICROWAVE ABSORBER
The generalized multilayer electromagnetic model of a
microwave absorber consists of N number of layers of
different materials with frequency dependent permittivity
and permeability available from a specific predefined
material database. This is backed by perfect electric
conductor (PEC) which acts as a perfect reflection backing
and consider as the last layer of the model (layer number
N+1).The electromagnetic wave of a specific frequency
travel through air (free space) which is consider as a layer
number 0 and incident obliquely to the first surface of the
multilayer structure making an incident angle θ with the
normal (z axis) at the point of incidence. This is illustrated
in Fig.1.Now the generalized reflection coefficient between
any two layers of the multilayer structure of the microwave
absorber can be evaluate from the concept of transmission
line theory[9], using the following algorithm:
)2exp(1
)2exp(
112,1
111,
1,
1,
2,1
iiii
iiii
ii
djkR
djkR
ii
ii
R
(1)
Where,
For TM (parallel) polarization:
11
11
1,
iiii
iiii
ii
kk
kk
i<N (2)
For TE (perpendicular) polarization:
11
11
1,
iiii
iiii
ii
kk
kk
i<N (3)
In the above equations,
i = frequency dependent complex permittivity of ith
layer.
i = frequency dependent complex permeability of ith
layer.
ik = wave number of the ith
layer and according to Snell‟s
law it is related with the incident angle θ as follows:
ik = )(sin2
00 ii
(4)
In equation (4), ω represents the frequency of the incident
wave whereas 0 and 0 denote the permittivity and
permeability of free space respectively, i.e.
m
F12
0 10854.8
(5)
m
H7
0 104
(6)
In this paper the most important fact regarding the design of
multilayer structure of the microwave absorber we have
taken into consideration is that for normal incidence of the
electromagnetic wave both TE and TM polarizations yield
the same magnitude of the reflection coefficient [8] and set
the reflection coefficient between the last layer of the
multilayer structure and the PEC (
R NN 1,
)to +1 for TM
polarization where as it set to -1 for TE polarization of the
electromagnetic wave. This seems to be neglected in many
papers [10,11,12], deals with the same problem and
wrongfully set to -1 for both TE and TM polarizations,
results in different values for the magnitude of the reflection
coefficient for normal incidence but which is not the case
actually. From this above consideration the overall
reflection coefficient of the multilayer absorber is now
computed recursively using the equations (1)-(6).
Fig -1: Physical model of multilayer microwave absorber
3. THE FITNESS FUNCTION
In this paper we mainly concentrate on the fact to find out
the particular set of materials with frequency dependent
permittivity and permeability available from a predefined
database of existing materials to minimize the overall
reflection coefficient of the multilayer microwave absorber.
The simulation is carried out for a particular frequency
band, wave polarization and angle of incidence. While
designing the same it is also desired that the thickness of the
multilayer structure should be least practically possible.
Therefore both these design requirement are taken into
consideration in the form of following fitness function:
𝑚𝑖𝑛𝑖𝑚𝑢𝑚𝐹 = 𝐾1*20𝑙𝑜𝑔10 (𝑚𝑎𝑥(|𝑅0,1|))+K2 𝑑𝑖
𝑁
𝑖=1 (7)
3. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 04 Issue: 07 | July-2015, Available @ http://www.ijret.org 421
Where along with the weighted sum of overall maximum
reflection coefficient of the multilayer microwave absorber,
the sum of all the individual layer thickness in meters is also
consider for optimization as well which makes our proposed
model more attractive in its grade. In the objective function
(7) K1, K2 are weighting constants emphasizing each of the
term associated with the fitness function and has been set to
K1=1 and K2= 1000 respectively for all cases.
4. ALGORITHM OVERVIEWS
4.1 Overview of BBO Algorithm
BBO algorithm is a population based search technique
having faster convergence rates. The basic concept of this
algorithm was first introduced by Dan Simon in 2008
motivated and influenced by the biological organism
distribution in time and space.
The steps evolved in BBO algorithm are as follows:
Step1: The BBO parameters like initialization of the
maximum species count, maximum rate of migration,
maximum rate of mutation, elitism parameter are initialized.
Step 2: The suitability index variable (SIV) of each island
which determine the potential solution to the given problem
are generate randomly.
Step 3: The SIV for each island is evaluated
Step 4: The number of elite islands that have highest
suitability index are identified
Step 5: Migration are performed probabilistically on those
SIVs of non-elite islands based on the probabilistic model
where PS (t) changes from time t to time t +∆𝑡 according to
the following relation:
PS (t +∆t ) = PS (t) (1-λS ∆t - µS ∆t ) + PS-1 (t) λS-1 ∆t + PS+1
(t) µS+1 ∆t
Where,
λS (immigration rate) = I ( 1 -
𝑆
𝑆𝑚𝑎𝑥
)
µS (emigration rate) =
𝐸𝑆
𝑆𝑚𝑎𝑥
S = Number of species in the habitat
𝑆𝑚𝑎𝑥 = maximum number of species supported by the
habitat
I = Maximum immigration rate
PS (t) = probability of the habitat
E = Maximum possible value of emigration rate
Step 6: Mutation operation is performed probabilistically on
those non-elite islands based on the mutation probability as:
m(S) = 𝑚 𝑚𝑎𝑥 (
1 − 𝑝 𝑠
𝑝 𝑚𝑎𝑥
)
Where,
m(S) = Mutation rate for habitat having S species
𝑚 𝑚𝑎𝑥 = Maximum mutation rate
𝑝 𝑚𝑎𝑥 =Mmaximum probability
Step 7: Repeat from steps 3 to 7 till the maximum number of
iterations reaches.
Figure below shows the species model of a single habitat for
BBO algorithm
Fig -2: Species model of a single habitat
4.2 Overview of FPA Algorithm
Flower pollination algorithm is most recently developed
nature inspired optimization algorithm. The concept was
first developed by Xin-She Yang in the year 2012.The basic
concept of this algorithm is based on the flower pollination
process where the pollination process carried out by the
varieties of pollinators like insects, bats, birds etc. In this
process the pollen from the male parts of a flower is carried
away to the female part called stigma of a flower by the
pollinator. Basically the pollination process is classified into
two categories, Biotic pollination process and Abiotic
pollination process. Insects and animals are acts as a
pollinator in case of Biotic pollination process whereas in
Abiotic pollination, pollination occurs through wind or
diffusion in water.
The steps evolved in Flower pollination algorithm are as
follows:
Step1: The population of n flowers/pollen gametes is
initialized randomly
Step2: The best solution 𝑔∗ is determined in the initial
population
Step3: Switch probability p ϵ [0, 1] is defined
Step4: while (t < Max Generation)
for i= 1 to n (all n flowers/pollen in the population)
Step5: if rand < p, d-dimensional step vector L is drawn
which satisfied L‟ evy distribution
Global pollination via 𝑥𝑖
𝑡+1
= 𝑥𝑖
𝑡
+ L (𝑔∗ − 𝑥𝑖
𝑡
)
Else
Draw ϵ from a uniform distribution in [0, 1]
Local pollination via 𝑥𝑖
𝑡+1
= 𝑥𝑖
𝑡
+ ϵ (𝑥𝑗
𝑡
+ 𝑥 𝑘
𝑡
)
End if
Step6: The new solutions are evaluated and updated them in
the population if they are found better.
Step7: end for
Step8: the current best solution 𝑔∗ is find out
Step9: end while
4.3 Overview of ABC Algorithm
The concept of ABC algorithm was first developed by
Basturk and Karaboga .This is also a very popular nature
inspired swarm based optimization algorithm .It consist of
three groups of bees known as employed bees, onlookers
and scouts. The searching ability of this algorithm is
4. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 04 Issue: 07 | July-2015, Available @ http://www.ijret.org 422
completely depends on the various behavior of these three
groups of bees. The positions of the food sources around a
colony of artificial bees give the solutions of an optimization
problem.
The steps evolved in Artificial bee colony optimization
algorithms are as follows:
Step1: Initialize „n‟ number of food positions or solutions
randomly in the„d‟ dimensional search space as :xi= [xi1, xi2,
…….,xid] where i=1,2,…….,n.
Step2: Evaluate objective function as per the relation:
fiti = {1/1+fi , if fi ≥0 },
fiti = { 1+abs(fi ) , if fi < 0 }where fi = value of the objective
function corresponding to ith solution.
Step3: The employed bees generated new solutions
according to the relation given as:
vij = xij+ randij(xij – xkj) where
vij= modified position of ith food source at jth dimension
rand= random number,k {1,2,……,n}andj {1,2,..,D }.
Step4: Evaluate new solutions and greedy selections are
applied.
Step5: Based on computed probability factor pi the onlooker
bees modify positions of some selected food sources
(solutions) and greedy selection are applied, where pi
=
𝑓𝑖𝑡 𝑖
𝑓𝑖𝑡 𝑚
𝑛
𝑚 =1
Step6: The solution which is generated by scout bee
replaced the abandoned solution in the population.
Step7: Record the best solution (gbest) and its corresponding
fitness (global fitness) value.
Step8: Repeat from steps 3 to 7 till the maximum number of
iterations reaches.
Table -1: Predefined Database of Existing Materials [7, 8]
Lossless dielectric material ( µr = 1+ j0)
# Ɛr
1 10+ j0
2 50+j0
Lossy Magnetic Materials
Ɛr = 15 + j0
µ = µr – j µi µr (f) = µr (1GHz) / f α
µi (f) = µi (1GHz) / f ß
# µr (1 GHz) α µi ( 1 GHz) ß
3 5 0.974 10 0.961
4 3 1.000 15 0.957
5 7 1.000 12 1.000
Lossy Dielectric Materials (µr = 1 + j0 )
Ɛ = Ɛr – jƐi Ɛr (f) = Ɛr (1GHz) / f α
Ɛi (f) = Ɛi (1GHz) / f ß
# Ɛr (1 GHz) α Ɛi (1 GHz) ß
6 5 0.861 8 0.569
7 8 0.778 10 0.682
8 10 0.778 6 0.861
Relaxation- Type Magnetic Materials
µ = µr – j µiµr = ( µm fm
2
) / (f2
+ fm
2
) µi = (µm fm f ) /
( f2
+ fm
2
)
(f and 𝒇 𝒎in GHz)
# µm fm
9 35 0.8
10 35 0.5
11 30 1.0
12 18 0.5
13 20 1.5
14 30 2.5
15 30 2.0
16 25 3.5
Table -2: Parametric setup of the BBO, FPA and ABC algorithms
BBO FPA ABC
Parameters Values Parameters Values Parameters Values
Population size 50 Population size 50 colony size (NP) 50
Number of elites 1 (for model
1,2,5,6,7,8)
Probability switch 0.8
Limit for
abandonment
5
Number of elites 2(for model 3,4) Mutation probability 3/d Food number NP/2
Search space
dimension
12
Search space dimension
(d)
12
Search space
dimension
12
Run no
20 Run no 20 Run no 20
Termination
condition
1000 iterations
max
Termination condition
1000 iterations
max
Termination
condition
1000
iterations
max
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5. SIMULATION RESULTS
The optimum results for the design of multilayer
microwave absorber using three very popular and newly
developed optimization algorithms Biogeography based
optimization algorithm (BBO), Flower pollination algorithm
(FPA) and Artificial bee colony optimization algorithm
(ABC) are presented in this section. The absorbers are
design for wide range of frequencies (0.2-20GHz) with a
frequency increase of 0.1 GHz at each step.8 different
models are optimized for oblique wide angle of incidence
(450
,600
) taking both TE and TM polarization of
electromagnetic wave under consideration. The models are
optimized taking overall reflection coefficient and total
thickness of the absorber simultaneously and only for
overall reflection coefficient of the microwave absorber
while total thickness is not taken into consideration for each
cases named as model1( optimized for oblique incidence,
450
TE polarization considering overall reflection
coefficient and total thickness of the absorber
simultaneously),model2(optimized for oblique incidence,
450
TE polarization considering only overall reflection
coefficient of the absorber, total thickness is not taken into
consideration),model3(optimized for 450
,TM polarization
considering overall reflection coefficient and total thickness
of the absorber at the same time),model4(optimized for 450
,
TM polarization considering overall reflection coefficient
while overall thickness is not considered here),model5( 600
TE polarization, overall reflection coefficient and total
thickness is optimized simultaneously),model6(600
,TE
polarization optimized for overall reflection coefficient of
the absorber and total thickness of the absorber is not taken
into consideration),model7(optimized for 600
TM
polarization and taken both overall reflection coefficient and
total thickness of the absorber into
consideration),model8(optimized for 600
TM polarization
and overall reflection coefficient of the absorber, total
thickness is not consider here for optimization).It has been
observed that for model1 BBO gives better frequency
response over the desired band of frequency while FPA
results in thinner absorber design as compare to all other
algorithms. In case of model2 again BBO comes out with
better frequency response over all other algorithms while
FPA is the better choice for thinner absorber design among
all other algorithms. For model3 it has been found that the
frequency response of BBO over the desired frequency band
is much better as compare to all other algorithms but for
thinner absorber design ABC is the better option. Similarly
for model4 BBO gives better frequency response and FPA
results in slightly thinner absorber design as compare to all
other algorithms. In case of model5 FPA performed slightly
better frequency response while BBO results in slightly
thinner absorber design as compare to all other algorithms.
For model6 it has been observed that the frequency response
of BBO is slightly superior over the desired frequency band
while ABC results in slightly thinner absorber design among
all other algorithms. Similarly in case of model7 again it has
been found that the frequency response of BBO is much
better over all other algorithms but regarding the thinner
absorber design FPA is the better choice and finally for
model8 it has been observed that BBO comes out with clear
winner in all relevant aspects over all other algorithms. The
simulated optimum results and their parametric and
statistical comparison for each models has been presented in
table 3,4,5.6,7,8,9,10,11,12,13,14,15,16,17 and 18
respectively for convenience. The frequency response and
the variation of mean of gbest value with iterations for all
the above models are presented in (figure 3-figure10) and
(figure 11- figure 18) respectively. For simulation all the
three algorithms are run for 20 independent trials and each
time the maximum number of iterations is set to 1000.
Fig -3: Reflection coefficient versus frequency (Model 1)
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Fig -4: Reflection coefficient versus frequency (Model 2)
Fig -5: Reflection coefficient versus frequency (Model 3)
Fig -6: Reflection coefficient versus frequency (Model 4)
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Fig -7: Reflection coefficient versus frequency (Model 5)
Fig -8: Reflection coefficient versus frequency (Model 6)
Fig -9: Reflection coefficient versus frequency (Model 7)
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Fig -10: Reflection coefficient versus frequency (Model 8)
Table -3: Parameters for microwave absorber (6 layers) design for oblique incidence (450
) TE polarization optimized for overall
reflection coefficient and total thickness of the absorber (Model 1)
Layer
BBO FPA ABC
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
1 16 0.2490 16 0.3131 16 0.2949
2 6 1.0680 6 0.7610 6 0.9064
3 14 0.1820 5 0.3094 4 0.1504
4 4 1.3406 8 0.1033 4 0.9517
5 4 0.8646 4 1.6098 5 0.3587
6 4 0.4290 4
0.5500
4 1.0092
Maximum reflection
coefficient in dB
-10.2835 -9.3841 -9.3679
Total thickness in mm 4.1332 3.6464 3.6713
Table -4: Comparative statistical analysis after 20 trials for the (Model 1)
Algorithm Best Worst Mean Standard deviation
BBO -6.1504 -5.9174 -6.0381 0.0447
FPA -5.7376 -4.8058 -5.2239 0.2489
ABC -5.6966 -4.5645 -5.2172 0.2684
Table -5: Parameters for microwave absorber (6 layers) design for oblique incidence (450
) TE polarization optimized for overall
reflection coefficient only (Model 2)
Layer
BBO FPA ABC
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
1 16 0.2381 16 0.2419 16 0.2582
2 6 0.7058 6 1.5529 6 1.8008
3 6 1.3697 14 0.4795 14 1.6236
4 16 0.8225 4 1.2493 15 0.9604
5 5 1.3354 1 0.6666 5 1.6358
6 5 1.7972 5 1.7116 4 1.1107
Maximum reflection
coefficient in dB
-11.7975 -11.2483 -11.0166
Total thickness in mm 6.2687 5.9018 7.3894
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Table -6: Comparative statistical analysis after 20 trials for the (Model 2)
Algorithm Best Worst Mean Standard deviation
BBO -11.7975 -10.0176 -11.0960 0.5646
FPA -11.2483 -9.8952 -10.6528 0.3813
ABC -11.0166 -9.4397 -10.0585 0.3416
Table -7: Parameters for microwave absorber (6 layers) design for oblique incidence (450
) TM polarization optimized for overall
reflection coefficient and total thickness of the absorber (Model 3)
Layer
BBO FPA ABC
Material
No.
Thickness
in mm
Material
No.
Thickness
in mm
Material
No.
Thickness
in mm
1 16 0.1030 16 0.1822 6 0.1833
2 6 1.4443 6 0.2693 16 0.2242
3 14 0.4268 6 0.8301 8 0.2721
4 8 0.7368 13 0.6979 6 0.7863
5 4 0.8402 4 1.5618 4 0.4257
6 4 1.8436 4 0.8225 4 1.7376
Maximum
Reflection
Coefficient in dB
-30.2481 -20.5088 -20.7433
Total thickness
in mm
5.3948 4.3638 3.6291
Table -8: Comparative statistical analysis after 20 trials for the (Model 3)
Algorithm Best Worst Mean Standard deviation
BBO -24.8533 -16.4655 -18.4980 1.9837
FPA -16.1449 -13.2480 -14.6000 0.8345
ABC -17.1142 -14.2078 -15.5004 0.8690
Table -9: Parameters for microwave absorber (6layers) design for oblique incidence (450
) TM polarization optimized for overall
reflection coefficient only (Model 4)
Layer
BBO FPA ABC
Material
No.
Thickness
in mm
Material
No.
Thickness
in mm
Material
No.
Thickness
in mm
1 16 0.1716 6 0.7208 16 0.1977
2 6 1.3317 16 0.2630 8 1.7055
3 4 0.8141 6 1.1166 5 0.9524
4 6 1.4537 4 0.8265 6 1.8200
5 7 0.2564 7 0.9604 4 1.8384
6 4 1.6368 4 1.6835 8 0.7691
Maximum
Reflection
Coefficient in dB
-25.2583 -22.3404 -22.7686
Total thickness
in mm
5.6643 5.5707 7.2831
Table -10: Comparative statistical analysis after 20 trials for the (Model 4)
Algorithm Best Worst Mean Standard deviation
BBO -25.2583 -17.7643 -22.4666 1.9788
FPA -22.3404 -18.1716 -19.4410 1.1317
ABC -22.7686 -18.4334 -19.8876 1.1233
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Table -11: Parameters for microwave absorber (6 layers) design for oblique incidence (600
) TE polarization optimized for overall
reflection coefficient and total thickness of the absorber (Model 5)
Layer
BBO FPA ABC
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
1 16 0.3169 16 0.3237 16 0.3130
2 6 0.7450 6 0.5223 6 0.5268
3 5 0.3574 6 0.4647 7 0.3742
4 5 0.5914 4 1.2836 4 1.3664
5 4 1.5383 4 0.5331 3 0.2648
6 4 0.1333 5 0.8065 4 0.9812
Maximum Reflection
Coefficient in dB
-6.6375 -6.6851 -6.5227
Total thickness in mm 3.6823 3.9339 3.8264
Table -12: Comparative statistical analysis after 20 trials for the (Model 5)
Algorithm Best Worst Mean Standard deviation
BBO -2.9551 -2.7778 -2.9053 0.0457
FPA -2.7513 -2.0113 -2.3090 0.1852
ABC -2.6963 -2.0615 -2.3877 0.1837
Table -13: Parameters for microwave absorber (6layers) design for oblique incidence (600
) TE polarization optimized for overall
reflection coefficient only (Model 6)
Layer
BBO FPA ABC
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
1 16 0.2586 16 0.2695 16 0.2594
2 6 1.9907 6 1.8572 6 1.8987
3 16 0.8464 15 0.9149 16 1.4822
4 5 1.7802 5 1.5704 5 1.5316
5 7 1.9986 6 1.6678 5 1.6458
6 3 1.9084 4 1.6473 15 0.2093
Maximum Reflection
Coefficient in dB
-8.0960 -7.7165 -7.7166
Total thickness in mm 8.7828 7.9272 7.0271
Table -14: Comparative statistical analysis after 20 trials for the (Model 6)
Algorithm Best Worst Mean Standard deviation
BBO -8.0960 -7.1832 -7.6399 0.2834
FPA -7.7165 -6.8083 -7.2663 0.2062
ABC -7.7166 -6.6386 -7.1055 0.3185
Table -15: Parameters for microwave absorber (6 layers) design for oblique incidence (600
) TM polarization optimized for overall
reflection coefficient and total thickness of the absorber (Model 7)
Layer
BBO FPA ABC
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
1 6 0.4691 6 0.2284 7 1.1456
2 8 1.0507 16 0.2784 13 0.3219
3 16 0.1029 2 0.5625 8 0.6492
4 4 0.3186 7 0.7283 6 1.5346
5 7 1.6255 6 0.4981 4 1.2964
6 4 1.5732 4 1.7882 4 0.4982
Maximum Reflection
Coefficient in dB
-33.7700 -25.2479 -27.5844
Total thickness in mm 5.1399 4.0839 5.4458
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Volume: 04 Issue: 07 | July-2015, Available @ http://www.ijret.org 429
Table -16: Comparative statistical analysis after 20 trials for the (Model 7)
Algorithm Best Worst Mean Standard deviation
BBO -28.6300 -18.3061 -22.1693 2.4139
FPA -21.1640 -16.1706 -19.0248 1.4408
ABC -22.1386 -17.1725 -19.0996 1.3767
Table -17: Parameters for microwave absorber (6layers) design for oblique incidence (600
) TM polarization optimized for overall
reflection coefficient only (Model 8)
Layer
BBO FPA ABC
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
Material
No.
Thickness in
mm
1 7 1.0262 8 0.3949 7 1.3312
2 15 0.4465 7 1.1760 14 0.3600
3 8 0.5817 13 0.3822 8 1.8722
4 2 0.5536 6 1.3205 12 1.0538
5 8 1.4546 7 1.4054 7 0.8118
6 4 1.8593 4 1.8743 4 1.7605
Maximum Reflection
Coefficient in dB
-36.6882 -26.9362 -26.8151
Total thickness in mm 5.9219 6.5533 7.1895
Table -18: Comparative statistical analysis after 20 trials for the (Model 8)
Algorithm Best Worst Mean Standard deviation
BBO -36.6882 -24.3533 -28.7182 3.0840
FPA -26.9362 -23.4013 -24.8761 0.7969
ABC -26.8151 -22.3841 -24.9769 1.0747
Fig -11: Mean of best fitness value versus iteration (Model 1)
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Fig -12: Mean of best fitness value versus iteration (Model 2)
Fig -13: Mean of best fitness value versus iteration (Model 3)
Fig -14: Mean of best fitness value versus iteration (Model 4)
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Fig -15: Mean of best fitness value versus iteration (Model 5)
Fig -16: Mean of best fitness value versus iteration (Model 6)
Fig -17: Mean of best fitness value versus iteration (Model 7)
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Fig -18: Mean of best fitness value versus iteration (Model 8)
6. CONCLUSION
The application of swarm based nature inspired optimization
algorithms namely Biogeography based optimization
algorithm (BBO), Flower pollination algorithm (FPA) and
Artificial bee colony optimization algorithm(ABC) for
synthesizing wideband multilayer microwave absorber has
been presented in this paper. The optimization has been
carried out for oblique wide angle (450
, 600
) of incidence
taking arbitrary polarization of the electromagnetic wave.
The comparative performance of BBO, FPA and ABC for
the optimum design of 8 different models of microwave
absorber has been presented. The study clearly established
the effectiveness of our proposed design for solving the
proper tradeoff between two very important conflicting
parameters such as overall reflection coefficient and total
thickness of the multilayer microwave absorber while
designing the same. It has also been traced out in this paper
that for normal incidence as both TE and TM yield the same
magnitude of the reflection coefficient hence it is required to
set the reflection coefficient between the PEC (
R NN 1,
) and
the last layer of the multilayer structure to +1 for TM
polarization and to -1 for TE polarization of the
electromagnetic wave which blatantly neglected in many
papers deals with the same problem.
REFERENCES
[1]. Eric Michielssen, Jean-Michel Sajer, S. Ranjithan, and
Raj Mittra, “Design of lightweight, broad-band microwave
absorbers using genetic algorithms,” IEEE Trans. on
Microwave Theory and Techniques, Vol. 41, No. 6/7, 1024–
1031, June/July 1993.
[2]. Weile, D., E. Michielssen, and D. Goldberg, “Genetic
algorithm design of pareto optimal broadband microwave
absorbers,” IEEE Trans. on Electromagnetic Compatibility,
Vol. 38, No.3, 518–525, August 1996.
[3]. Macedo, J., M.de Sousa, and V. Dmitriev, Optimization
of wideband multilayer microwave absorbers for any angle
of incidence and arbitrary polarization,
“International conference on Microwave and
Optoelectronics”, 558-561, Brasilia, Brazil, 2005.
[4]. S. Chamaani, S. A. Mirtaheri, M. Teshnehlab, M. A.
Shoorehdeli and V. Seydi, “Modified multi-objective
particle swarm optimization for electromagnetic absorber
design,” Progress In Electromagnetics Research, Vol. 79,
353–366, 2008.
[5]. Chamaani, S., S. Mirtaheri, and M. Shooredeli, “Design
of very thin wide band absorbers using modified local best
particle swarm optimization,” AEU- Int. J. Electron.
Commun, Vol. 62, 549–556, 2008.
[6]. L. Jiang, J. Cui, L. Shi, X. Li, “Pareto optimal design of
multilayer microwave absorbers for wide-angle incidence
using genetic algorithms”, IET Microwaves, Antennas&
Propagation, Vol. 3,Iss. 4, pp. 572–579, 2009.
[7]. M. J. Asi and N. I. Dib, “Design of multilayer
microwave broadband absorbers using central force
optimization,” Progress In Electromagnetics Research B,
Vol. 26, 101-113, 2010.
[8]. N. Dib, M. Asi, and A. Sabbah, “On the optimal design
of multilayer microwave absorbers,” Progress In
Electromagnetics Research C, Vol. 13, 171–185, 2010.
[9]. Chew, W. C., Waves and Fields in Inhomogeneous
Media, IEEE Press, New York, 1995.
[10]. L. Jiang J. Cui L. Shi X. Li, "Pareto optimal design of
multilayer microwave absorbers for wide-angle incidence
using genetic algorithms", IET Microwave, Antennas&
Propagation., Vol. 3, Iss. 4, pp. 572–579, 2009.
[11]. Goudos, S., “Design of microwave broadband
absorbers using a self-adaptive differential evolution
algorithm,” Int. J. RF and Microwave CAE, Vol. 19,
pp.364–372, May 2009.
[12]. Michielssen, E., J. Sajer, S. Ranjithan, and R. Mittra,
“Design of lightweight, broad-band microwave absorbers
using genetic algorithms,” IEEE Trans. on Microwave
15. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 04 Issue: 07 | July-2015, Available @ http://www.ijret.org 433
Theory and Techniques, Vol. 41, No. 6/7, pp.1024–1031,
June/July 1993.
[13]. L. Jiang J. Cui L. Shi X. Li, "Pareto optimal design of
multilayer microwave absorbers for wide-angle incidence
using genetic algorithms", IET Microwave, Antennas&
Propagation., Vol. 3, Iss. 4, pp. 572–579, 2009.
[14]. J. Kennedy and R. C. Eberhart, “Particle swarm
optimization,” Proc. IEEE Int. Conf. Neural Networks, pp.
1942–1948, Perth, Australia, 1995.
[15]. W. T. Li, X. W. Shi and Y. Q. Hei, “An Improved
Particle Swarm Optimization Algorithm for Pattern
Synthesis of Phased Arrays,” Progress In Electromagnetics
Research, Vol. 82, pp.319–332, 2008.
[16]. J. Robinson, and Y. Rahmat-Samii, “Particle swarm
optimization in electromagnetics,” IEEE Transactions on
Antennas and Propagation, Vol. 52, No. 2, pp.397–407,
February 2004.
[17]. N. Jin and Y. Rahmat-Samii, “Advances in particle
swarm optimization for antenna designs: Real-number,
binary, single- objective and multi objective
implementations,” IEEE Transactions on Antennas and
Propagation. Vol. 55, no. 3, pp.556-567, March 2007.
[18]. T. B. Chen, Y. L. Dong, Y. C. Jiao, and F. S. Zhang,
“Synthesis of circular antenna array using crossed particle
swarm optimization algorithm,” Journal of Electromagnetic
Waves and Appl., Vol. 20, No. 13, pp.1785–1795, 2006.
[19]. D. W. Boeringer,and D. H.Werner, “Particle swarm
optimization versus genetic algorithms for phased array
synthesis,” IEEE Transactions on Antennas and
Propagation, Vol. 52, No. 3, pp.771–779, 2004.
[20]. Bansal, J. C., P. K. Singh, Mukesh Saraswat,
AbhishekVerma, Shimpi Singh Jadon, and Ajith Abraham.
"Inertia weight strategies in particle swarm optimization."
IEEE Third World Congress on Nature and Biologically
Inspired Computing (NaBIC), Salamanca, Spain, pp. 633-
640, 2011.
[21]. Liang,J. J., and PonnuthuraiNagaratnamSuganthan.
"Dynamic multi-swarm particle swarm optimizer."
Proceedings IEEE Swarm Intelligence Symposium, 124-129,
Pasadena, California, SIS 2005.
[22]. K. R. Mahmoud, M. I. Eladawy, R. Bansal, S. H.
Zainud-Deen, and S. M. M. Ibrahem, “Analysis of uniform
circular arrays for adaptive beamforming applications using
particle swarm optimization algorithm,” International
Journal of RF and Microwave Computer-Aided
Engineering, vol. 18, no. 1, pp. 42-52, January 2008.
[23]. Urvinder Singh, Harish Kumar and Tara Singh Kamal,
“Design of Yagi-Uda Antenna Using Biogeography Based
Optimization,” IEEE Transactions on Antennas and
Propagation, Vol.58, No.10, pp.3375-3379, October 2010.
[24]. U Singh, T.S.Kamal, “Synthesis of thinned planar
concentric circular antenna arrays using biogeography-based
optimization,” IET Microw. Antennas Propag., Vol. 6, Iss.
7, pp. 822–829, 2012.
[25]. Dan Simon, “Biogeography-Based Optimization,”
IEEE Trans. on Evolutionary Computation, Vol.12, No.6.
December 2008.
[26]. N. Sakib, Md. Wasi UI Kabir, Md Subbir, Mohammad
Shafiul Alam, “A Comparative Study of Flower Pollination
Algorithm and Bat Algorithm on Continuous Optimization
Problems,” International Journal of Applied Information
Systems, Vol.7, No.9, September 2014.
[27]. Karaboga, D., Basturk, B., and “Artificial bee colony
(ABC) optimization algorithm for solving constrained
optimization problems, In LNCS: Advances in Soft
Computing: Foundations of Fuzzy Logic and Soft
Computing, Springer-Verlag, vol. 4529, 789–798, 2007.
[28]. Karaboga, D.; Basturk, B.: A powerful and efficient
algorithm for numerical function optimization: artificial bee
colony (ABC) algorithm. J. Global Optim., 39 (3) , 459–
471, 2007.
BIOGRAPHIES
JyotirmayTewary received his Bachelor
of Engineering (B.E) degree in
Electronics & Telecommunication
Engineering from Amravati University
Maharashtra, India and M.Tech from
National Institute of Technology
Durgapur, India. Presently he is working
towards his PhD in Electronics & Communication
Engineering from National Institute of Technology
Durgapur, India.
Email:tewaryjyotirmay@gmail.com
G.K.Mahanti was born in the year 1967
in West Bengal, India. He obtained his
B.E. in Electronics & Communication
Engg. from NIT, Durgapur, India, M.E.
in Electronics System and
Communication from NIT, Rourkela,
India and Ph.D(Engg.) from IIT,
Kharagpur, India. He has more than 20 years of teaching
and research experience. Presently he is working as
Professor, department of Electronics and Communication
Engineering, National Institute of Technology, Durgapur,
India. He is a senior member of IEEE, USA. His research
area is Array antenna synthesis, Evolutionary Algorithms
&Electromagnetics.
Email:gautammahanti@yahoo.com
KajlaBasu completed her M.Sc and
Ph.D degree in Mathematics from
IIT,Kharagpur.She has published 40
papers in international & national
journals and conference proceedings.
She is presently a professor in the
department of Mathematics,NIT,
Durgapur. She was also former head of the department of
Mathematics. Her research area is operation research and
statistical analysis.
Email:kajla.basu@gmail.com