This document describes the design and simulation of a dual-fed circularly polarized microstrip patch antenna for WLAN applications at 2.4 GHz. A circular patch antenna with a diameter of 30 mm is designed on an FR4 substrate with a dielectric constant of 4.6 and thickness of 1.6 mm. Circular polarization is achieved by feeding the patch from two points with a 90 degree phase difference using a 3dB hybrid coupler. The antenna is simulated using ADS software. Simulation results show the antenna resonates at 2.404 GHz with a return loss of -28.003 dB and gain of 6.368 dB. The antenna provides circular polarization as required for WLAN applications.
In this paper, UWB technology operating in broad
frequency range of 3.1-10.6 GHz has shown great achievement
for high- speed wireless communications. to satisfy the UWB
system requirements, a band pass filter with a broad pass
band width, low insertion loss, and high stop-band suppression.
UWB band-pass filter (BPF) with wireless local area network
(WLAN) notch at 5.8 GHz and 3-dB fractional bandwidth of
108% using a microstrip structure is presented. Initially a
two transmission pole UWB band pass filter in the frequency
range 3.1-10.6 GHz is achieved by design a parallel-coupled
microstrip line with defective ground plane structure using
GML 1000 substrate with specification: dielectric constant 3.2
and thickness 0.762 mm at centre frequency 6.85 GHz. In this
structure a ë/4 open circuited stub is introduced to achieve the
notch at 5.8 GHz to avoid the interference with WLAN
frequency with lies the desired UWB band. The design
structure was simulated on electromagnetic circuit simulation
software and fabricated by microwave integrated circuit
technique. The measured VNA results show the close
agreement with simulated results.
DESIGN AND ANALYSIS OF COMPACT UWB BAND PASS FILTERijeljournal
This paper presents design, implementation and analysis of an ultra-wideband (UWB) band-pass-filter using parallel-coupled microstrip line with defective ground plane and a uniform multi-mode resonator. The structure of the filter is designed on microwave substrate GML 1000 of dielectric constant 3.2 and height is 0.762 mm. Simulation is carried out by CST MSW software and optimized structure is fabricated. The frequency response is measured on vector analyzer and measured results show close approximation with simulation results. In this article modeling of the proposed filter is also reported. The electric model of the filter is analyzed by circuit theory and MATLAB. This model is validated by comparing the results with the CST simulation and VNA measured results. This filter is compact in size of dimension 30˟1.87 mm2 may be useful for modern wireless application of communication.
Design and analysis of compact uwb band pass filterijeljournal
This paper presents design, implementation and analysis of an ultra-wideband (UWB) band-pass-filter using parallel-coupled microstrip line with defective ground plane and a uniform multi mode resonator. The structure of the filter is designed on microwave substrate GML 1000 of dielectric constant 3.2 and
height is 0.762 mm. Simulation is carried out by CST MSW software and optimized structure is fabricated. The frequency response is measured on vector analyzer and measured results show close approximation with simulation results. In this article modeling of the proposed filter is also reported. The
electric model of the filter is analyzed by circuit theory and MATLAB. This model is validated by comparing the results with the CST simulation and VNA measured results. This filter is compact in size of dimension 30˟1.87 mm2 may be useful for modern wireless application of communication.
Inter-connected coupled lines resonator topology for bandpass filter applicat...IJECEIAES
This paper presents an inter-connected side-shorted coupled-line resonator topology as a base cell. The base cell is built from two single-shorted quarter-wavelength coupled-line sections, connected in series to give a halfwavelength coupled-line that creates a single resonance of bandpass filter response. Higher-order bandpass filter is produced by adding new singleshorted coupled-line sections, cascaded in an inter-connected manner to the base cell. This new topology creates a unique arrangement that caused cross coupling effects between the resonators, resulting to the occurrence of transmission zeros that lead to the improvement of selectivity of the higher order bandpass filter response. For validation of concept, 2 nd order bandpass filters were fabricated using microstrip technology on Roger 3210 substrate with parameter of Ɛr=10.2, h=1.27 mm and tan δ=3x10-3. The filters were measured and the results show good agreement with simulation results. and 3 rd
3D FSS with multiple transmission zeros and pseudo elliptic responsejournalBEEI
The three-dimensional frequency selective surface (3D FSS) with band reject multiple transmission zeros and pseudo-elliptic response is designed from two-dimensional (2D) periodic array of shielded micro strip lines to realize wide out-of–band radio wave rejection. The 3D FSS array consists of multimode cavities whose coupling with air can be controlled to obtain a desired frequency range. The proposed FSS with shorting via to ground exhibits pseudo-elliptic band-reject response in the frequency range from 6GHz to 14GHz. As the plane wave of linear polarization incidents perpendicularly to the shielded micro strip line with perfect electric conductor (PEC) and perfect magnetic conductor (PMC) boundary walls, two quasi-TEM modes are obtained known as air mode and substrate mode. The first 3D FSS design is a combination of two or more resonators. Furthermore, second 3D FSS design with three shorting vias result more elliptic band reject frequency response and a pass band transmission pole. All in phase resonators of design give transmission poles and out of phase combination of resonators give transmission zeros respectively. The proposed 3D FSS is designed and simulated using Ansys HFSS software. These designs exhibit an improved performance for many practical applications such as antenna sub-reflector, and spatial filters.
Comparison of Three Different Cancellation Schemes for Orthogonal Frequency D...ijtsrd
Orthogonal Frequency Division Multiplexing OFDM is an exceptional case of Frequency Division Multiplexing. The dilemma of OFDM is its sensitivity to frequency offset between the transmitted and received carrier frequencies. This frequency offset establishes Inter Carrier Interference ICI Cancellation in the OFDM symbol. ICI reduction methods have been had by OFDM. This research considers three ICI self cancellation SC , maximum likelihood ML estimation, and extended Kalman filter EKF method. These three methods are compared in terms of bit error rate performance, bandwidth efficiency, and computational complexity. For high values of the frequency offset and for higher order modulation schemes, the SC method does not as well as the ML and EKF methods. Simulation results using MATLAB software. Ma Khin Saw | Aye Aye Khine ""Comparison of Three Different Cancellation Schemes for Orthogonal Frequency Division Multiplexing (OFDM) System"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25182.pdf
Paper URL: https://www.ijtsrd.com/engineering/electronics-and-communication-engineering/25182/comparison-of-three-different-cancellation-schemes-for-orthogonal-frequency-division-multiplexing-ofdm-system/ma-khin-saw
In this paper, UWB technology operating in broad
frequency range of 3.1-10.6 GHz has shown great achievement
for high- speed wireless communications. to satisfy the UWB
system requirements, a band pass filter with a broad pass
band width, low insertion loss, and high stop-band suppression.
UWB band-pass filter (BPF) with wireless local area network
(WLAN) notch at 5.8 GHz and 3-dB fractional bandwidth of
108% using a microstrip structure is presented. Initially a
two transmission pole UWB band pass filter in the frequency
range 3.1-10.6 GHz is achieved by design a parallel-coupled
microstrip line with defective ground plane structure using
GML 1000 substrate with specification: dielectric constant 3.2
and thickness 0.762 mm at centre frequency 6.85 GHz. In this
structure a ë/4 open circuited stub is introduced to achieve the
notch at 5.8 GHz to avoid the interference with WLAN
frequency with lies the desired UWB band. The design
structure was simulated on electromagnetic circuit simulation
software and fabricated by microwave integrated circuit
technique. The measured VNA results show the close
agreement with simulated results.
DESIGN AND ANALYSIS OF COMPACT UWB BAND PASS FILTERijeljournal
This paper presents design, implementation and analysis of an ultra-wideband (UWB) band-pass-filter using parallel-coupled microstrip line with defective ground plane and a uniform multi-mode resonator. The structure of the filter is designed on microwave substrate GML 1000 of dielectric constant 3.2 and height is 0.762 mm. Simulation is carried out by CST MSW software and optimized structure is fabricated. The frequency response is measured on vector analyzer and measured results show close approximation with simulation results. In this article modeling of the proposed filter is also reported. The electric model of the filter is analyzed by circuit theory and MATLAB. This model is validated by comparing the results with the CST simulation and VNA measured results. This filter is compact in size of dimension 30˟1.87 mm2 may be useful for modern wireless application of communication.
Design and analysis of compact uwb band pass filterijeljournal
This paper presents design, implementation and analysis of an ultra-wideband (UWB) band-pass-filter using parallel-coupled microstrip line with defective ground plane and a uniform multi mode resonator. The structure of the filter is designed on microwave substrate GML 1000 of dielectric constant 3.2 and
height is 0.762 mm. Simulation is carried out by CST MSW software and optimized structure is fabricated. The frequency response is measured on vector analyzer and measured results show close approximation with simulation results. In this article modeling of the proposed filter is also reported. The
electric model of the filter is analyzed by circuit theory and MATLAB. This model is validated by comparing the results with the CST simulation and VNA measured results. This filter is compact in size of dimension 30˟1.87 mm2 may be useful for modern wireless application of communication.
Inter-connected coupled lines resonator topology for bandpass filter applicat...IJECEIAES
This paper presents an inter-connected side-shorted coupled-line resonator topology as a base cell. The base cell is built from two single-shorted quarter-wavelength coupled-line sections, connected in series to give a halfwavelength coupled-line that creates a single resonance of bandpass filter response. Higher-order bandpass filter is produced by adding new singleshorted coupled-line sections, cascaded in an inter-connected manner to the base cell. This new topology creates a unique arrangement that caused cross coupling effects between the resonators, resulting to the occurrence of transmission zeros that lead to the improvement of selectivity of the higher order bandpass filter response. For validation of concept, 2 nd order bandpass filters were fabricated using microstrip technology on Roger 3210 substrate with parameter of Ɛr=10.2, h=1.27 mm and tan δ=3x10-3. The filters were measured and the results show good agreement with simulation results. and 3 rd
3D FSS with multiple transmission zeros and pseudo elliptic responsejournalBEEI
The three-dimensional frequency selective surface (3D FSS) with band reject multiple transmission zeros and pseudo-elliptic response is designed from two-dimensional (2D) periodic array of shielded micro strip lines to realize wide out-of–band radio wave rejection. The 3D FSS array consists of multimode cavities whose coupling with air can be controlled to obtain a desired frequency range. The proposed FSS with shorting via to ground exhibits pseudo-elliptic band-reject response in the frequency range from 6GHz to 14GHz. As the plane wave of linear polarization incidents perpendicularly to the shielded micro strip line with perfect electric conductor (PEC) and perfect magnetic conductor (PMC) boundary walls, two quasi-TEM modes are obtained known as air mode and substrate mode. The first 3D FSS design is a combination of two or more resonators. Furthermore, second 3D FSS design with three shorting vias result more elliptic band reject frequency response and a pass band transmission pole. All in phase resonators of design give transmission poles and out of phase combination of resonators give transmission zeros respectively. The proposed 3D FSS is designed and simulated using Ansys HFSS software. These designs exhibit an improved performance for many practical applications such as antenna sub-reflector, and spatial filters.
Comparison of Three Different Cancellation Schemes for Orthogonal Frequency D...ijtsrd
Orthogonal Frequency Division Multiplexing OFDM is an exceptional case of Frequency Division Multiplexing. The dilemma of OFDM is its sensitivity to frequency offset between the transmitted and received carrier frequencies. This frequency offset establishes Inter Carrier Interference ICI Cancellation in the OFDM symbol. ICI reduction methods have been had by OFDM. This research considers three ICI self cancellation SC , maximum likelihood ML estimation, and extended Kalman filter EKF method. These three methods are compared in terms of bit error rate performance, bandwidth efficiency, and computational complexity. For high values of the frequency offset and for higher order modulation schemes, the SC method does not as well as the ML and EKF methods. Simulation results using MATLAB software. Ma Khin Saw | Aye Aye Khine ""Comparison of Three Different Cancellation Schemes for Orthogonal Frequency Division Multiplexing (OFDM) System"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25182.pdf
Paper URL: https://www.ijtsrd.com/engineering/electronics-and-communication-engineering/25182/comparison-of-three-different-cancellation-schemes-for-orthogonal-frequency-division-multiplexing-ofdm-system/ma-khin-saw
Design of Microstrip UWB Bandpass Filter using open-circuited resonatorsIJERD Editor
A compact band pass filter with a fractional bandwidth of 59% is designed for Ultra Wide Band (UWB) applications using a microstrip structure consisting of open circuit resonators. Transmission zeros are utilized at the passband edges to enhance the signal selectivity. The filter is characterized by sharp roll-off characteristics due to the presence of transmission zeros. The insertion loss and return loss are found to be 0.1dB and -15dB respectively. This filter has a measured 3-dB passband of (3 to 5.5) GHz, with a compact size of (13.2 x 9.7) mm. The filter offers desirable performance for the lower-band frequency of a UWB system and exhibits low insertion loss. As the structure comprises of only transmission line sections and no coupling gap, the filter is made easy for fabrication. This UWB BPF is useful to alleviate the strong WLAN signals interference to UWB receivers. To illustrate the concept, band pass filter was designed using Agilent® ADS software and simulated results are obtained.
Design and optimization of microstrip filtering antenna with modified shaped ...TELKOMNIKA JOURNAL
This paper presents a new compact microstrip filtering antenna with modified shaped slots to improve the impedance bandwidth. The proposed microstrip filtering antenna consists of three parts; the monopole radiating patch antenna, the SIR filter, and the feeding microstrip line. The design structure is achieved on one sided glass epoxy FR-4 substrate with dielectric constant ε_r = 4.4 and thickness of h = 1.6 mm. The design procedures of the proposed filtering antenna starts from the second order Chebyshev low pass filter prototype. The simulation results throughout this article are done by a computer simulation technology (CST) software. The simulated results have been achieved show good performance of S11-parameter and broad side antenna gain on +z-direction. This design has two transmission zeros at 5.4 GHz and 7.7 GHz, and bandwidth (B.W) of about 1.66 GHz so; it is suitable for high speed data communication. This design has good skirt selectivity.
In this paper, a low pass filter based on T-Shaped resonator is presented. The T-Shaped resonator consists of meandered lines and rectangular patches. Also, the LC model and transfer function of the proposed resonator is presented. For suppression of spurious harmonics, a bandstop structure consists of hexangular patches and open stubs has been utilized. Finally, the wide stopband microstrip lowpass filter with cutoff frequency 2.72 GHz has been simulated, fabricated and measured. The LPF has good characteristics such as wide stopband and insertion loss lower than 0.18 dB in the passband region. The rejection level is less than -20 dB from 2.98 up to 21.3 GHz. The filter size is 10.5 mm×12.7 mm, or 0.131 λg× 0.158 λg, where λg is the guided wavelength. The measured and simulated results of the filter is in good agreement with each other, which show the merits of low insertion loss and wide stopband.
Design and Realization of 2.4GHz Branch-line CouplerQuang Binh Pham
In the scope of this paper, a branch-line coupler working at 2.4GHz is designed and realized. The experiment results are consequently compared to the simulation results.
Coplanar waveguide low pass filter based on square complementary split ring r...TELKOMNIKA JOURNAL
In this paper, we present a novel coplanar waveguide low pass filter (LPF)structure based on the use of square complementary split ring resonators (CSRRs) in order to enhance the performances of a low pass filter. Especially, to enlarge the bandwidth of the LPF, the insertion losses and to increase the rejection of the LPF. The CSRRs are optimised and inserted periodically along the center conductor of the CPW line with a CPW ground integrating stubs permitting to enlarge the bandwidth. The simulation results of this filter show a -3 dB cut-off frequency equal to fc = 5.28 GHz. The designed filter has a good rejection in the stop band which below -20 dB and presents a good insertion loss in the bandwidth. The proposed filter has been fabricated and tested which give a good agreement between simulation and measurement results, the whole dimensions of the validated filter are 35.48x21.16 mm2. The originality of this work is the wide rejection band and the miniature dimensions.
A Compact UWB BPF with a Notch Band using Rectangular Resonator Sandwiched be...IJECEIAES
This paper presents a compact design of an ultra wide band bandpass filters with a notch band using interdigital structure. The aim of the design is to reduce the size of filter, reduce the complexity of the design, and improve the performance of filter response. The proposed filter comprises of a rectangular resonator sandwiched between Interdigital structures, with rectangular slot as defected microstrip structure at the input and output ports. This design has been used for the first time to achieve the above aim. The advantage with this design is that, it does not use any via or defected ground structure. The insertion loss of proposed filter, in passband between 3.1 GHz to 10.8 GHz, is less than 0.7dB, and for the notched band it is 21.5 dB centred at 7.9 GHz. The proposed filter is fabricated, tested and compared with simulated results. The proposed design was small in size with less complexity, and shows performance better than the other designs available in the literatures at this dimension.
A Probe-Fed Patch Antenna with a Step-Shaped Ground Plane for 2.4 GHz Access ...Saou-Wen Su
This Letter demonstrates a new design of a probe-fed patch antenna with a modified antenna ground, and a constructed prototype ideal for applications in a 2.4-GHz WLAN access point is presented. The antenna has a thick air substrate for broadband operation and is fed by an inclined probe pin at the edge of the patch bent portion. The antenna ground comprises different portions and is in the shape of a step. With the proposed probe feed and ground configuration, good impedance bandwidth with VSWR below 1.5 over the 2.4 GHz WLAN band can be obtained. In addition, good broadside radiation characteristics have also been observed.
Investigation of Integrated Rectangular SIW Filter and Rectangular Microstrip...IJASCSE
This paper presents an investigation based on the resonant circuit approach to characterize an integrated microwave filter and antenna from a lumped element prototype. This approach is used to design an integrated filter and antenna to reduce the overall size of the physical dimensions of the RF/microwave front-end subsystem. This study focuses on the integration of a rectangular Substrate Integrated Waveguide (SIW) filter with a rectangular microstrip patch antenna to produce a filtering and radiating element in a single device. The physical layouts of the SIW filter and rectangular microstrip patch antenna based on single- and dual-mode will be developed. To prove the concept, the integrated microwave filter and antenna at a center frequency of 2 GHz is demonstrated and validated through simulation and laboratory experiments. The experimental performance yielded promising results that were in good agreement with the simulated results. This study is beneficial for microwave systems, given that the reduction of the complexity of design and physical dimension as well as cost are important for applications such as base stations and multiplexers in wireless communication systems.
3.4-3.9GHz Parallel Coupled Bandpass Filter with High Stopband Rejection and ...IJERA Editor
This paper presents the design, fabrication, and measurement of 3.4-3.9 GHz parallel coupled microstrip
bandpass filter. The EM simulation results indicate that the insertion loss varies between -1dB and -0.795dB at
the desired frequency band. Both input and output VSWRs show the maximum value of 1.28. More than 40dB
rejections out of band are witnessed at the stopbands of DC-2.7GHz and 4.85-7.45GHz. In contrast, the
measured insertion loss is a little poorer, changing from -1.87dB to -2.59dB, and above 40dB suppression is also
recorded at the same stopbands. A little higher input and output VSWRs, 1.415 and 1.404 are achieved in the
fabricated filter. These results demonstrate that the developed filter can be applied in 3.4-3.9GHz
communication systems.
This paper deals with the channel loss models of ultra-wideband radio wave propagation from 2 to 10 GHz application. IEEE 802.15.4a and Okumura channel loss reference models have been introduced and the estimation methods of channel transmission loss have been discussed with the environments of 2 to 10 GHz short range application. The channel transmission loss was measured in ZigBee circuit with 2 kinds of power, using IEEE 802.15.4a and Okumura channel model to estimate the theoretical channel loss, the theoretical value and the actual measured value were compared and analyzed. The analysis shows that the error between the calculated value and the actual measured value of the IEEE 802.15.4a reference model is small in the ultra-wideband ZigBee channel environment, and the error of the Okumura channel loss model is large. The results show that in the environments of 2 to 10 GHz short range application, IEEE 802.15.4a channel loss model is a high precision reference model for the ultra-wideband channel loss calculation.
A novel cross-coupled microstrip bandpass filter with hairpin-DGS resonators ...TELKOMNIKA JOURNAL
This paper introduces a new design of a cross-coupled microstrip bandpass filter (MBPF) based on hairpin defected ground structure (DGS) resonators using accurate coupling matrix (CM) technique for microwave communication systems. The article presents the equivalent circuit of the suggested MBPF based on the DGS equivalent circuit model derived from the equivalent inductance and capacitance that occurs despite the presence of the slots disrupting the current in the ground layer. The paper investigates also the different external coupling mechanisms that the feed configuration affects significantly the filter response. In this paper, a four order Chebyshev topology has been adopted for designing the filter to suppress harmonics and achieve a very compact size and a wide stopband with two transmission zeros.
Modelling And Miniaturization of A 2-Bits Phase Shifter Using Koch Fractal Sh...IJERA Editor
Phase shifter is a key component in phase array antenna for the Radar application and the wireless communication system. This paper presents a novel design of miniaturised 2bits phase shifter using Koch fractal shapes of one iteration orders. The 3-section branch line coupler is used to extend the bandwidth of the phase shifter,this type of coupler is characterised by a low cost and simplicity of fabrication.Using the Koch fractal geometry the circuit size of the coupler is reduced to 6.36cm ×2.14cm at 2.4GHz. The simulation results show a good performance. So, over 2.1GHz-2.7GHzThe novel design of 2bits fractal reflection phase shifter based on the 3section show a return loss less than -20dB and the phase error varied between 0.1° and 0.4°for the four output phases . The circuit size of the phase shifter is reduced to9.5cm×2.1cm.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
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Microstrip patch antenna for pcs and wlaneSAT Journals
Abstract Due to development in wireless devices, it poses a new challenge for the design of an antenna in wireless communication. Patch antennas are well suited for various wireless application systems due to their low weight, low profile, versatility, conformability, low cost and low sensitivity to manufacturing tolerances. This paper present design, simulation of a rectangular micro strip antenna for WLAN and PCS. The aim of the work is to design reliable broadband, compact patch antenna for wireless devices. Antenna is proposed which is providing circular polarization, dual band, resonant frequencies at 1.9 GHz, 2.4 GHz. Key Words: Patch antenna, co-axial feeding, polarization, dual band, HFSS …
Design of Microstrip UWB Bandpass Filter using open-circuited resonatorsIJERD Editor
A compact band pass filter with a fractional bandwidth of 59% is designed for Ultra Wide Band (UWB) applications using a microstrip structure consisting of open circuit resonators. Transmission zeros are utilized at the passband edges to enhance the signal selectivity. The filter is characterized by sharp roll-off characteristics due to the presence of transmission zeros. The insertion loss and return loss are found to be 0.1dB and -15dB respectively. This filter has a measured 3-dB passband of (3 to 5.5) GHz, with a compact size of (13.2 x 9.7) mm. The filter offers desirable performance for the lower-band frequency of a UWB system and exhibits low insertion loss. As the structure comprises of only transmission line sections and no coupling gap, the filter is made easy for fabrication. This UWB BPF is useful to alleviate the strong WLAN signals interference to UWB receivers. To illustrate the concept, band pass filter was designed using Agilent® ADS software and simulated results are obtained.
Design and optimization of microstrip filtering antenna with modified shaped ...TELKOMNIKA JOURNAL
This paper presents a new compact microstrip filtering antenna with modified shaped slots to improve the impedance bandwidth. The proposed microstrip filtering antenna consists of three parts; the monopole radiating patch antenna, the SIR filter, and the feeding microstrip line. The design structure is achieved on one sided glass epoxy FR-4 substrate with dielectric constant ε_r = 4.4 and thickness of h = 1.6 mm. The design procedures of the proposed filtering antenna starts from the second order Chebyshev low pass filter prototype. The simulation results throughout this article are done by a computer simulation technology (CST) software. The simulated results have been achieved show good performance of S11-parameter and broad side antenna gain on +z-direction. This design has two transmission zeros at 5.4 GHz and 7.7 GHz, and bandwidth (B.W) of about 1.66 GHz so; it is suitable for high speed data communication. This design has good skirt selectivity.
In this paper, a low pass filter based on T-Shaped resonator is presented. The T-Shaped resonator consists of meandered lines and rectangular patches. Also, the LC model and transfer function of the proposed resonator is presented. For suppression of spurious harmonics, a bandstop structure consists of hexangular patches and open stubs has been utilized. Finally, the wide stopband microstrip lowpass filter with cutoff frequency 2.72 GHz has been simulated, fabricated and measured. The LPF has good characteristics such as wide stopband and insertion loss lower than 0.18 dB in the passband region. The rejection level is less than -20 dB from 2.98 up to 21.3 GHz. The filter size is 10.5 mm×12.7 mm, or 0.131 λg× 0.158 λg, where λg is the guided wavelength. The measured and simulated results of the filter is in good agreement with each other, which show the merits of low insertion loss and wide stopband.
Design and Realization of 2.4GHz Branch-line CouplerQuang Binh Pham
In the scope of this paper, a branch-line coupler working at 2.4GHz is designed and realized. The experiment results are consequently compared to the simulation results.
Coplanar waveguide low pass filter based on square complementary split ring r...TELKOMNIKA JOURNAL
In this paper, we present a novel coplanar waveguide low pass filter (LPF)structure based on the use of square complementary split ring resonators (CSRRs) in order to enhance the performances of a low pass filter. Especially, to enlarge the bandwidth of the LPF, the insertion losses and to increase the rejection of the LPF. The CSRRs are optimised and inserted periodically along the center conductor of the CPW line with a CPW ground integrating stubs permitting to enlarge the bandwidth. The simulation results of this filter show a -3 dB cut-off frequency equal to fc = 5.28 GHz. The designed filter has a good rejection in the stop band which below -20 dB and presents a good insertion loss in the bandwidth. The proposed filter has been fabricated and tested which give a good agreement between simulation and measurement results, the whole dimensions of the validated filter are 35.48x21.16 mm2. The originality of this work is the wide rejection band and the miniature dimensions.
A Compact UWB BPF with a Notch Band using Rectangular Resonator Sandwiched be...IJECEIAES
This paper presents a compact design of an ultra wide band bandpass filters with a notch band using interdigital structure. The aim of the design is to reduce the size of filter, reduce the complexity of the design, and improve the performance of filter response. The proposed filter comprises of a rectangular resonator sandwiched between Interdigital structures, with rectangular slot as defected microstrip structure at the input and output ports. This design has been used for the first time to achieve the above aim. The advantage with this design is that, it does not use any via or defected ground structure. The insertion loss of proposed filter, in passband between 3.1 GHz to 10.8 GHz, is less than 0.7dB, and for the notched band it is 21.5 dB centred at 7.9 GHz. The proposed filter is fabricated, tested and compared with simulated results. The proposed design was small in size with less complexity, and shows performance better than the other designs available in the literatures at this dimension.
A Probe-Fed Patch Antenna with a Step-Shaped Ground Plane for 2.4 GHz Access ...Saou-Wen Su
This Letter demonstrates a new design of a probe-fed patch antenna with a modified antenna ground, and a constructed prototype ideal for applications in a 2.4-GHz WLAN access point is presented. The antenna has a thick air substrate for broadband operation and is fed by an inclined probe pin at the edge of the patch bent portion. The antenna ground comprises different portions and is in the shape of a step. With the proposed probe feed and ground configuration, good impedance bandwidth with VSWR below 1.5 over the 2.4 GHz WLAN band can be obtained. In addition, good broadside radiation characteristics have also been observed.
Investigation of Integrated Rectangular SIW Filter and Rectangular Microstrip...IJASCSE
This paper presents an investigation based on the resonant circuit approach to characterize an integrated microwave filter and antenna from a lumped element prototype. This approach is used to design an integrated filter and antenna to reduce the overall size of the physical dimensions of the RF/microwave front-end subsystem. This study focuses on the integration of a rectangular Substrate Integrated Waveguide (SIW) filter with a rectangular microstrip patch antenna to produce a filtering and radiating element in a single device. The physical layouts of the SIW filter and rectangular microstrip patch antenna based on single- and dual-mode will be developed. To prove the concept, the integrated microwave filter and antenna at a center frequency of 2 GHz is demonstrated and validated through simulation and laboratory experiments. The experimental performance yielded promising results that were in good agreement with the simulated results. This study is beneficial for microwave systems, given that the reduction of the complexity of design and physical dimension as well as cost are important for applications such as base stations and multiplexers in wireless communication systems.
3.4-3.9GHz Parallel Coupled Bandpass Filter with High Stopband Rejection and ...IJERA Editor
This paper presents the design, fabrication, and measurement of 3.4-3.9 GHz parallel coupled microstrip
bandpass filter. The EM simulation results indicate that the insertion loss varies between -1dB and -0.795dB at
the desired frequency band. Both input and output VSWRs show the maximum value of 1.28. More than 40dB
rejections out of band are witnessed at the stopbands of DC-2.7GHz and 4.85-7.45GHz. In contrast, the
measured insertion loss is a little poorer, changing from -1.87dB to -2.59dB, and above 40dB suppression is also
recorded at the same stopbands. A little higher input and output VSWRs, 1.415 and 1.404 are achieved in the
fabricated filter. These results demonstrate that the developed filter can be applied in 3.4-3.9GHz
communication systems.
This paper deals with the channel loss models of ultra-wideband radio wave propagation from 2 to 10 GHz application. IEEE 802.15.4a and Okumura channel loss reference models have been introduced and the estimation methods of channel transmission loss have been discussed with the environments of 2 to 10 GHz short range application. The channel transmission loss was measured in ZigBee circuit with 2 kinds of power, using IEEE 802.15.4a and Okumura channel model to estimate the theoretical channel loss, the theoretical value and the actual measured value were compared and analyzed. The analysis shows that the error between the calculated value and the actual measured value of the IEEE 802.15.4a reference model is small in the ultra-wideband ZigBee channel environment, and the error of the Okumura channel loss model is large. The results show that in the environments of 2 to 10 GHz short range application, IEEE 802.15.4a channel loss model is a high precision reference model for the ultra-wideband channel loss calculation.
A novel cross-coupled microstrip bandpass filter with hairpin-DGS resonators ...TELKOMNIKA JOURNAL
This paper introduces a new design of a cross-coupled microstrip bandpass filter (MBPF) based on hairpin defected ground structure (DGS) resonators using accurate coupling matrix (CM) technique for microwave communication systems. The article presents the equivalent circuit of the suggested MBPF based on the DGS equivalent circuit model derived from the equivalent inductance and capacitance that occurs despite the presence of the slots disrupting the current in the ground layer. The paper investigates also the different external coupling mechanisms that the feed configuration affects significantly the filter response. In this paper, a four order Chebyshev topology has been adopted for designing the filter to suppress harmonics and achieve a very compact size and a wide stopband with two transmission zeros.
Modelling And Miniaturization of A 2-Bits Phase Shifter Using Koch Fractal Sh...IJERA Editor
Phase shifter is a key component in phase array antenna for the Radar application and the wireless communication system. This paper presents a novel design of miniaturised 2bits phase shifter using Koch fractal shapes of one iteration orders. The 3-section branch line coupler is used to extend the bandwidth of the phase shifter,this type of coupler is characterised by a low cost and simplicity of fabrication.Using the Koch fractal geometry the circuit size of the coupler is reduced to 6.36cm ×2.14cm at 2.4GHz. The simulation results show a good performance. So, over 2.1GHz-2.7GHzThe novel design of 2bits fractal reflection phase shifter based on the 3section show a return loss less than -20dB and the phase error varied between 0.1° and 0.4°for the four output phases . The circuit size of the phase shifter is reduced to9.5cm×2.1cm.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Microstrip patch antenna for pcs and wlaneSAT Journals
Abstract Due to development in wireless devices, it poses a new challenge for the design of an antenna in wireless communication. Patch antennas are well suited for various wireless application systems due to their low weight, low profile, versatility, conformability, low cost and low sensitivity to manufacturing tolerances. This paper present design, simulation of a rectangular micro strip antenna for WLAN and PCS. The aim of the work is to design reliable broadband, compact patch antenna for wireless devices. Antenna is proposed which is providing circular polarization, dual band, resonant frequencies at 1.9 GHz, 2.4 GHz. Key Words: Patch antenna, co-axial feeding, polarization, dual band, HFSS …
A bandwidth reconfigurable antenna for devices in low UWB-applicationsTELKOMNIKA JOURNAL
A reconfigurable simple design planar antenna for ultra-wideband applications is proposed, with E-shaped slot contained four narrow vertical slots that has the capacity of switching using four PIN diodes with a ground plan and a microstrip power line. An additional circularly polarized (CP) band is obtained by changing the on/off states of the PIN diodes. Moreover, the four PIN diodes are attached in the middle of the E-shape slot and used to switch the radiation flow of the patch. For validation, a patch antenna design is offered, based on a distinctive situation analysis. The antenna offers the low-ultra-wideband (UWB) frequencies band. Therefore, the switch of the operating states of PIN diodes gives us a good bandwidth re-configurability. In addition, with this flexible configuration we achieve a good -10 dB bandwidths with the ability to change the bandwith ranges from narrow-band 2.3 GHz to wide-band 3.1 GHz. Also, we achieve a large band for 3 dB AR is 2.57 GHz.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
A dual-frequency microstrip patch antennas has been presented and used for 802.11WLAN
applications. The antennas had been designed, simulated and parametrically studied in CST Microwave
studio. By introducing u-slot, dual-band operation with its operating mode centered at frequency 2.4GHz,
3.65GHz and 5.2GHz had been obtained. The gain and directivity had been improved by adjusting the
parameters of the antennas. The gain of the proposed designs was 6.019dBi, 4.04dBi and 6.22dBi and
directivity was 6.02dBi, 4.05dBi and 6.22dBi at resonant frequencies 2.4GHz, 3.6GHz and 5.2GHz
respectively. The patch antennas had been proposed to be used in portable devices that require
miniaturized constituent parts.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
It was our first real life based designing experience on this platform. From the mentioned designed we tried to develop a prototype of Dipole antenna of 600 Mhz for practical uses. For the further development we’ve a got plan to use a simulation software like CST microwave studio or ADS to simulate our developed design in the long term . We had to work very hard to complete this design in time! But in the end, the challenge and learning experience were well worth it.
Cube satellite missions perform innovative scientific experiments on a low cost developmental platform but
have an inherent limitation of size and space. This restricts the total available solar power that can be
harnessed and as a result, the radio links operate on stringent power budgets. For improving the available
margins for communication in such satellites, it is desirable to improve upon the antenna system
performance at the ground station used for the establishment of the links with the satellite. This can be
achieved by improving the forward gain, the forward to backward ratio and the directivity of the antenna.
This paper describes the electrical simulations and the performance evaluation of the one unit, two unit and
four unit circularly polarized crossed Yagi-Uda antenna array designed for communication with amateur
radio (HAM) satellites operating over the 434 MHz to 438 MHz Amateur UHF band. The electro-magnetic
model has been developed using the 4NEC2 software. The simulations have been validated with the
practical field testing performed for estimating the SWR, antenna gain, the forward to backward ratio and
radiation pattern for the antenna system.
A Compact Reconfigurable Dual Band-notched Ultra-wideband Antenna using Varac...TELKOMNIKA JOURNAL
In this paper, a reconfigurable dual band-notched ultra-wideband (UWB) antenna is presented.
The antenna design consists of a circular shape with two pairs of the L-resonator. To realize the notch
characteristics in WLAN at 5.2 GHz and 5.8 GHz bands, the half wavelength of the L-resonator is
introduced in the design. The T-shaped notch is etched in the ground to enhance the bandwidth which
covers the UWB operating frequency range from 3.219–10.863 GHz. The proposed reconfigurable dual
band-notched UWB antenna shows good impedance matching for the simulated in the physical layout.
Furthermore, the proposed antenna has a compact size of 37.6x28 mm2. This proposed reconfigurable
design can provide an alternative solution for the wireless system in the designing of a band-notched
antenna with a good tuning capability.
Circularly polarized microstrip antenna with reactive load design for wireles...BASIM AL-SHAMMARI
This paper presents a design of microstrip antenna for IEEE 802.11b and for IEEE 802.11g using a nearly square patch antenna, excited by a standard miniature adapter probe feed line. The patch and ground plain are separated by a substrate; the radiating patch is loaded by a central shorting pin and feeding probe loaded by a series capacitor. This antenna has wide bandwidth in the frequency band of (WLAN) and with a return loss ≤ −10 dB from 2.4 GHz to 2.48 GHz exhibits circularly polarized far field radiation pattern.
The proposed antennas have been simulated and analyzed using method of moments (MoM) based software package Microwave Office 2008 v8.0. The results show that the bandwidth of the antenna increases by using reactive load. The simulated gain of the antenna is over 6 dB.
Circularly polarized microstrip antenna with reactive load design for wireles...BASIM AL-SHAMMARI
Abstract
This paper presents a design of microstrip antenna for IEEE 802.11b and for IEEE 802.11g using a nearly square patch antenna, excited by a standard miniature adapter probe feed line. The patch and ground plain are separated by a substrate; the radiating patch is loaded by a central shorting pin and feeding probe loaded by a series capacitor. This antenna has wide bandwidth in the frequency band of (WLAN) and with a return loss ≤ −10 dB from 2.4 GHz to 2.48 GHz exhibits circularly polarized far field radiation pattern.
The proposed antennas have been simulated and analyzed using method of moments (MoM) based software package Microwave Office 2008 v8.0. The results show that the bandwidth of the antenna increases by using reactive load. The simulated gain of the antenna is over 6 dB.
Multiband Circular Microstrip Patch Antenna for WLAN Applicationtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
Slack (or Teams) Automation for Bonterra Impact Management (fka Social Soluti...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on the notifications, alerts, and approval requests using Slack for Bonterra Impact Management. The solutions covered in this webinar can also be deployed for Microsoft Teams.
Interested in deploying notification automations for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
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UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
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Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
JMeter webinar - integration with InfluxDB and GrafanaRTTS
Watch this recorded webinar about real-time monitoring of application performance. See how to integrate Apache JMeter, the open-source leader in performance testing, with InfluxDB, the open-source time-series database, and Grafana, the open-source analytics and visualization application.
In this webinar, we will review the benefits of leveraging InfluxDB and Grafana when executing load tests and demonstrate how these tools are used to visualize performance metrics.
Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
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- Demonstration of InfluxDB and Grafana using a practice web application
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Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
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Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
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https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
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Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
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• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered Quality
A010510105
1. IOSR Journal of Electronics and Communication Engineering (IOSR-JECE)
e-ISSN: 2278-2834,p- ISSN: 2278-8735.Volume 10, Issue 5, Ver. I (Sep - Oct .2015), PP 01-05
www.iosrjournals.org
DOI: 10.9790/2834-10510105 www.iosrjournals.org 1 | Page
Dual Feed Microstrip Patch Antenna for Wlan Applications
Dinesh kannan.R1
, Jisnu.P2
12
Scholar, SRM University, Chennai - 603203, India.
Abstract: Microstrip patch antennas represent one family of compact antennas that offer a conformal nature
and the capability of ready integration with communication system’s printed circuitry. In this paper, a 2.4 GHz
circular polarization microstrip antenna is designed and simulated. The selected microstrip antenna is a dual–
fed circular polarized microstrip antenna. The antenna consists of circular patch and 3 dB hybrid coupler. The
dual – fed circular polarized microstrip antenna is etched on a FR4 with dielectric substrate of 4.6 with the
height of 1.6 mm. Circular polarization is obtained when two orthogonal modes are equally excited with 90°
phase difference between them. Circular polarization is important because regardless of the receiver
orientation, it will always be receiving a component of the signal. This is due to the resulting wave having an
angular variation.
Keywords: Microstrip patch antenna, Hybrid coupler, circular patch, Polarization, WLAN.
I. Introduction
Wireless LAN can be used either to replace wired LAN or as an extension of the wired LAN
infrastructure. There are in general two types of antennas for WLAN applications, fixed WLAN base stations or
access points, and the other is for mobile communication terminals. For base station applications, impedance
matching for WLAN bandwidth should be better than 1.5:1 VSWR or about 14 dB return loss, similar to the
cellular system base station. Antenna that capable to excite circular polarization is very attractive because it can
overcome the multipath fading problem, thus enhance the system performance, especially indoor WLAN
operation. Currently, the most commonly used WLAN system is the IEEE 802.11b System. A key requirement
of WLAN system is that it should be low profile, where it is almost invisible to the user. For this reason, the
microstrip patch antennas are the antennas of choice for WLAN use due to their small real estate area and the
ability to be designed to blend into the surroundings.
II. Microstrip Patch Antenna
All In its most basic form, a Microstrip Patch antenna consists of a radiating patch on one side of a
dielectric substrate which has a ground plane on the other side. The patch is generally made of conducting
material such as copper or gold and can take any possible shape. The radiating patch and the feed lines are
usually photo etched on the dielectric substrate.
III. Directional Coupler
Generally branch-line couplers are 3dB, four ports directional couplers having a 90 phase difference
between its two output ports named through and coupled arms. Branch-line couplers (also named as Quadrature
Hybrid) are often made in microstrip line form.
Fig.1 3dB Hybrid coupler
Power dividers and directional couplers, are passive devices used in the field of radio technology such
as power division or power combining. A 3 dB, 90° hybrid coupler is a four-port device, that is used either to
2. Dual Feed Microstrip Patch Antenna for Wlan Applications
DOI: 10.9790/2834-10510105 www.iosrjournals.org 2 | Page
equally split an input signal with a resultant 90° phase shift between output signals or to combine two signals
while maintaining high isolation between them. However, in a practical device the amplitude balance is
frequency dependent and departs from the ideal 0dB difference. All 90° Power Dividers/Combiners, also known
as quadrature hybrids or simply quad hybrids, are reciprocal four port networks. Fig.1 is a functional block
diagram of a 3 dB quad hybrid coupler. The hybrid coupler, or 3 dB directional coupler, in which the two
outputs are of equal amplitude, takes many forms. It is beginning when quadrature (90 degree) 3 dB coupler
coupling with outputs 90 degrees out of phased. Now any matched 4-port with isolated arms and equal power
division is called a hybrid or hybrid coupler. Today the characterizing feature is the phase difference of the
outputs. If 90 degrees, it is a 90 degree hybrid. If 180 degrees, it is a 180 degree hybrid. This terminology
defines the power difference in dB between the two output ports of a 3 dB hybrid. In an ideal hybrid circuit, the
difference should be 0 dB.
Fig. 2 Internal diagram of 3dB quad hybrid coupler
Referring to Fig.2, a signal applied to port 1 splits equally between ports 2 and 3 with one of the
outputs exhibiting a relative 90° phase shift. If ports 2 and 3 are properly terminated into matching impedances,
nearly all the signal applied to port 1 is transmitted to the loads connected to ports 2 and 3. In this circumstance,
port 4 receives negligible power and is termed isolated. However, if there is an impedance mismatch at port 2,
for example, then signal power reflected back from port 2 were divided proportionally between ports 1 and 4.
Power is not fed to port 3.
IV. Microstrip Antenna Polarization
A. Polarization types
Polarization of an antenna is defined as the polarization of the wave transmitted (radiated) by the
antenna, whereas polarization of radiated wave is defined as property of an electromagnetic wave describing the
time varying direction and relative magnitude of the electric field vector; specifically, the figure traced as a
function of time by the extremity of the vector at fixed location in the space, and the sense in which it is traced,
as observed along the direction of propagation. Polarization may be classified as linear, circular and elliptical.
a) Linear polarization
If the vector that describes the electrical field at a point in space as a function of time is always directed
along a line, the field is said to be linearly polarized. The polarization can also be determined by the propagating
antenna. Linear polarized electromagnetic (EM) wave. Linear polarized can be horizontal.
b) Circular polarization
A circular polarized wave radiates energy in both the horizontal and vertical planes and all planes in
between. Fig 4.5 below shows the electromagnetic (EM) wave for circular polarization. Circular polarization
occurs when two signals of equal amplitude but have 90° phase shifted. Circular polarization can result in Left
Hand circularly polarized (LHCP).Where the wave is rotating anticlockwise, or Right Hand circularly polarized
(RHCP) which denotes a clockwise rotation.
V. Design Of Microstrip Patch And Hybrid Coupler
The following specifications are used to design the microstrip antenna Substrate: Fr4, Dielectric
Constant εr =4.6, Operating Frequency: 2.4 GHz, Input Impedance: 50 Ohm, Thickness of the Substrate: 1.6
mm, Polarization: Circular Polarization.
In order to design a circular microstrip patch antenna operating at resonant frequency fr = 2.4 GHz, a
suitable dielectric substrate of relative permittivity εr = 4.6 and of thickness h=1.6 mm is chosen. Now we uses
following two equations to calculate the radius of circular patch
3. Dual Feed Microstrip Patch Antenna for Wlan Applications
DOI: 10.9790/2834-10510105 www.iosrjournals.org 3 | Page
where
Using above equations the radius is found to be a =30 mm at resonant frequency f r =2.4 GHz.
Calculated Hybrid coupler design for B=5.519, Length=16.81mm, W=2.958mm for B=7.884 Length of the
hybrid=13.115mm, W=5.135mm.
VI. Simulated Results
The simulation of circular microstrip antenna is done on ADS software and we get simulation results of
return loss, Gain, 3D E- fields.
Fig.3 Schematic diagram of 3dB hybrid coupler in ADS
Fig.4 Return loss for Hybrid coupler
Fig.5 Proposed Antenna Layout design in ADS2009
Fig.6 3D view of Patch Antenna
4. Dual Feed Microstrip Patch Antenna for Wlan Applications
DOI: 10.9790/2834-10510105 www.iosrjournals.org 4 | Page
Fig.7 Return loss of Proposed Microstrip patch antenna
Fig.8 3D Radiation Pattern of Patch Antenna
Fig.9 Gain and Directivity of Proposed Microstrip antenna
Fig.10 Efficiency of Proposed Microstrip antenna
5. Dual Feed Microstrip Patch Antenna for Wlan Applications
DOI: 10.9790/2834-10510105 www.iosrjournals.org 5 | Page
Fig.11 Effective Area of Microstrip antenna
Fig.12 Radiated power of Microstrip antenna
Table I: Simulated Circular Polarized Microstrip Patch Antenna Results
Specifications Observation
Frequency(GHz) 2.404
Return Loss (dB) -28.003
Power radiated(W) 2.1x104
Effective angle 1.57615
Gain 6.36836
Directivity 9.01612
Efficiency 55%
Maximum intensity 1.26896x104
HPBW(dB) 85.1496
VII. Conclusion
There are various types of microstrip antennas able to excite a circular polarization. In this paper, dual
fed circular polarization microstrip antenna was chosen. The microstrip antenna is design to operate at 2.404
GHz frequency. The dual fed circular polarization microstrip antenna is successfully implemented and
fabricated. The microstrip antenna resonates at 2.404 GHz and gives better return loss, which is -28.003 dB. The
proposed antenna given better value because only 0.47 % power is reflected and 99.53 % power is transmitted.
The VSWR of the microstrip antenna is 1.2:1, which shows that the level of mismatched for the microstrip
antenna is not very high. The bandwidth of this microstrip antenna is better, which is 17.04 % and the maximum
radiation occurs at -40° with gain of 6.36dB. The Microstrip antenna is said to be circular if the axial ratio is 0
dB. From the calculation of axial ratio, most of the angles give 0 dB value, thus prove that the microstrip
antenna polarize circularly.
References
[1] Pramendra Tilanthe, P. C. Sharma, and T. K. Bandopadhyay, “Gain Enhancement of Circular Microstrip Antenna for Personal
Communication Systems,” IACSIT International Journal of Engineering and Technology, Vol.3, No.2, April 2011.
[2] J. -Y. Park, C. Caloz, Y. Qian, and T. Itoh, “A compact circularly polarized subdivided microstrip patch antenna,” IEEE Microwave
Wireless Component Letters, vol. 12, pp. 18-19, Jan 2002.
[3] S. Zhang, C. Zhu, J. K. O. Sin, and P. K. T. Mok, “A novel ultrathin elevated channel low-temperature poly-Si TFT,” IEEE
Electron Device Lett., vol. 20, pp. 569–571, Nov. 1999.
[4] D. A. El Aziz and R. Hamad, “ Wideband Circular Microstrip Antenna For Wireless Communication Systems,” Radio Science
Conference, pp. 1-8, March 2007.
[5] Constantine. A. Balanis, “ Antenna Theory Analysis and Design,”2nd ed., John Wiely and Sons,Inc., 1997.
[6] N. A. Zakaria, A. A. Sulaiman., and M. A. A. Latip, “Design of a Circular Microstrip Antenna,”IEEE International RF and
Microwave Proceedings, pp. 289-292, December 2008.
[7] Jieh-Sen Kuo and Gui-Bin Hsieh, “Gain Enhancement of a Circularly Polarized Equilateral-Triangular Microstrip Antenna with a
Slotted Ground Plane,” IEEE Transactions on Antennas and Propagation, vol. 51, no. 7, July 2003.