Frequency reconfigurable antennas are very attractive for many wireless applications.They offer many advantages such as simplicity and compactness. In this electronicpaper, we propose a reconfigurable antenna operating in the S and C bands. Theproposed antenna uses a BAP65-02 RF diode to switch between the ultra widebandfrom 2.92 to 6.19 GHz to the narrowband from 2.92 to 3.93 GHz. The ultra widebandis obtained by a partial rectangular ground plane with a symmetrical rectangular slotand the narrowband is obtained by adding a parasitic element electrically connectedto the ground plane by the PIN diode when it is positively biased. This patch antennaoperates in the Federal Communications Commission band (FCC) and can be used forbiomedical applications such as radiometry imaging. The numerical simulation resultsbased on the finite element method and the finite integral method show a very goodagreement between them.
A novel autonomous wireless sensor node for IoT applicationsTELKOMNIKA JOURNAL
A novel wireless sensor network node (WSNN) is presented in this paper where the solar energy
harvester system is used as an autonomous power solution for endless battery lifetime. In this sensor
node, the meander-line Inverted-F-Antenna (MIFA) is proposed and integrated in a single-CC2650 chip of
Texas Instrument. The simple structure, low cost, compact size, high efficiency and low power
consumption are advantages of this single-chip WSNN. The experimental results show that MIFA antenna
is promising solution to enhance communication performance in WSN. In addition, the investigated
single-chip WSNN with multi-wireless technologies including Bluetooth Low Energy and Zigbee as well as
6LowPAN is an attractive device for internet of thing (IoT) applications.
A rectangular tuneable ultra-wideband (UWB) microstrip patch (MP) antenna based on a single sheet of graphene (SSG) is designed in this study. The antenna band can be tuned by applying a DC voltage bias perpendicular to the SSG at various values via adjusting the input impedance. The antenna has been analyzed by computer simulation technology (CST) microwave studio (MWS) software using an FR4 substrate of thickness 1.6 mm with a dielectric permittivity 휀푟= 4.4 and loss tangent tan = 0.02 fed by a 50 Ω microstrip line frequency. The design is compact since the antenna consists mostly of copper and the SSG. Graphene’s low weight, high flexibility, and strength make it more attractive than other semiconductor materials. Then, the study investigates the effects of applying the electrical characteristics of graphene to the antenna’s length, which varies with the ON and OFF states. This UWB MP antenna is also designed with notch characteristics so that it can reject undesired interference signals. Subsequently, this compact UWB MP antenna with tuneable resonance frequency is suitable for most wireless communication applications. The simulation results work in the 3.1 to 10 GHz range, as required for UWB technology.
Frequency Reconfiguration Mechanism of a PIN Diode on a Reconfigurable Antenn...IJECEIAES
Microstrip patch antennas are increasingly gaining popularity for usage in portable wireless system applications due to their light weight, low profile structure, low cost of production and robust nature. The patch is generally made of a conducting material such as copper or gold and can take any possible shapes, but rectangular shapes are generally used to simplify analysis and performance prediction. Microstrip patch antenna radiates due to the fringing fields between the patch edge and ground plane. In this work, a frequency reconfigurable antenna with a BAR63-02V Positive-IntrinsicNegative (PIN) diode is designed, simulated and fabricated. The antenna operates at 2.686GHz for Long-Term Evolution (LTE2500) and 5.164GHz for Wireless Local Area Network (WLAN) applications. In the OFF state, the antenna operates at 5.302GHz, which is also suitable for WLAN application. The proposed antenna is fabricated on a FR-4 substrate with a relative dielectric constant, ε r of 4.5, thickness, h of 1.6mm and loss tangent, tan δ of 0.019. The fabrication process is carried out at the Advanced Printed Circuit Board (PCB) Design Laboratory in UTHM.
Miniature design of T-Shaped frequency Reconfigurable antenna for S-Band Appl...IJECEIAES
The article presents a miniature antenna with a simple geometry and a simple approach for reconfiguration. In order to make the T-shaped antenna frequency reconfigurable, we integrated Switches in specific positions. The location of the switches is determined following a study of the distribution of the surface currents of the suggested antenna. Indeed, we found that the insertion of switches in places where the concentrations of surface currents are high is irrelevant. In fact, to redirect current flow, the PIN diodes or RF Switch must be placed in positions where the distribution of the surface currents is of low concentration. These locations facilitate the establishment of new trajectories of the flux of current. As a result, a miniature tunable antenna dimension 20mm*20mm*1.6mm printed on FR4 substrate with 4.4 permittivity and with 0.04 loss tangent, the antenna can be adopted in many communication devices in view of its small size, its low manufacturing cost and performance on frequency sweep, the antenna operates in S-Band with an acceptable band and gain. The antenna is simulated and optimized using CST Microwave Studio.
Designing an Antenna System That Can Perform Conditional RF to DC Harnessing ...IOSRJECE
Electromagnetic energy or RF energy will play a pivotal role in wireless technology and wireless communication in the impending future. The paper proposes a concept for a patch antenna based system that can harness RF energy upon triggering and can convert the harnessed RF to DC from the radio frequency of 1 GHz to 3 GHz, the design frequency is 2.4GHz. The patch antenna system contains a high gain patch antenna along with a wireless communicating module and a conversion circuit. The return loss of the antenna is approximately 27.1dB. The power gain is 30.1 dBm .The converter circuit is designed in), Multi-Sim to get an output voltage of around 5V that can be used to power a mobile-device or maybe stored in a battery. The triggering part is done with the help of a T-mote which is simulated in a network simulator, Cooja. The patch antenna is simulated in High Frequency Structural Simulator
Compact reconfigurable PIFA antenna for wireless applicationsTELKOMNIKA JOURNAL
This paper presents, new compact and multiband frequency reconfigurable planar inverted-F antenna (PIFA). The antenna is designed and optimized to cover mobile application devices like GPS, WLAN/Wi-Fi, WiMAX, 4G LTE, UWB, and satellite applications. The frequency reconfigurability is obtained by using only a single RF switch (PIN diode) for changing the operating frequency. The antenna dimensions are 45.6x39.6x1.6 mm3 printed on an FR-4 epoxy substrate with relative dielectric constant εr = 4.3, loss tangent tan (δ) = 0.002 and 50 Ω coaxial feed line. The proposed antenna has two patches connected by a single PIN diode. The antenna introduces nine resonant frequencies under (S11 ≤ -10 dB) which are: 0.980 GHz, 3.392 GHz, 3.924 GHz, 4.554 GHz, 5.82 GHz, 6.81 GHz, 7.305 GHz, 8 GHz and 8.105 GHz in the ON and OFF states of the PIN diode which are applicable to cover GSM900, WLAN/Wi-Fi, WiMAX, 4G LTE, UWB, and satellite systems. The obtained maximum simulated gain is 8.45 dB at 6.81 GHz. The lowest return loss is obtained to be -42 dB at 5.854 GHz. Detailed simulation and measurement results are explored and studied in this research. The CST software is used to simulate and optimize the proposed PIFA antenna. The proposed antenna has been fabricated and produced a good agreement with the simulation results.
Circularly polarized antenna array based on hybrid couplers for 5G devicesjournalBEEI
This paper depicts a wideband circularly polarized (CP) antenna for 5G devices. The antenna array has a 3D structure including four simple printed dipole elements with directional radiations, high gain, and high efficiency. It achieves a CP by using the sequential rotation (SR) feeding based on 90°-3dB hybrid couplers in the proposed feeding network. The antenna array bandwidth is wide, 26.7%, with an operating frequency band from 3.35 GHz to 4.35 GHz. The antenna achieves a high peak gain of 10.73 dBi and high efficiency of 93.75%. Besides, the antenna gain is stable over the operating bandwidth (BW). At the centre operating frequency of 3.75 GHz, the angle of circular polarization is 51°. The antenna is designed and fabricated on the Rogers 4003 C substrate. The measured S11 is well matching with the simulation results. With the above characteristics, the proposed antenna can be a suitable candidate for 5G devices.
A novel autonomous wireless sensor node for IoT applicationsTELKOMNIKA JOURNAL
A novel wireless sensor network node (WSNN) is presented in this paper where the solar energy
harvester system is used as an autonomous power solution for endless battery lifetime. In this sensor
node, the meander-line Inverted-F-Antenna (MIFA) is proposed and integrated in a single-CC2650 chip of
Texas Instrument. The simple structure, low cost, compact size, high efficiency and low power
consumption are advantages of this single-chip WSNN. The experimental results show that MIFA antenna
is promising solution to enhance communication performance in WSN. In addition, the investigated
single-chip WSNN with multi-wireless technologies including Bluetooth Low Energy and Zigbee as well as
6LowPAN is an attractive device for internet of thing (IoT) applications.
A rectangular tuneable ultra-wideband (UWB) microstrip patch (MP) antenna based on a single sheet of graphene (SSG) is designed in this study. The antenna band can be tuned by applying a DC voltage bias perpendicular to the SSG at various values via adjusting the input impedance. The antenna has been analyzed by computer simulation technology (CST) microwave studio (MWS) software using an FR4 substrate of thickness 1.6 mm with a dielectric permittivity 휀푟= 4.4 and loss tangent tan = 0.02 fed by a 50 Ω microstrip line frequency. The design is compact since the antenna consists mostly of copper and the SSG. Graphene’s low weight, high flexibility, and strength make it more attractive than other semiconductor materials. Then, the study investigates the effects of applying the electrical characteristics of graphene to the antenna’s length, which varies with the ON and OFF states. This UWB MP antenna is also designed with notch characteristics so that it can reject undesired interference signals. Subsequently, this compact UWB MP antenna with tuneable resonance frequency is suitable for most wireless communication applications. The simulation results work in the 3.1 to 10 GHz range, as required for UWB technology.
Frequency Reconfiguration Mechanism of a PIN Diode on a Reconfigurable Antenn...IJECEIAES
Microstrip patch antennas are increasingly gaining popularity for usage in portable wireless system applications due to their light weight, low profile structure, low cost of production and robust nature. The patch is generally made of a conducting material such as copper or gold and can take any possible shapes, but rectangular shapes are generally used to simplify analysis and performance prediction. Microstrip patch antenna radiates due to the fringing fields between the patch edge and ground plane. In this work, a frequency reconfigurable antenna with a BAR63-02V Positive-IntrinsicNegative (PIN) diode is designed, simulated and fabricated. The antenna operates at 2.686GHz for Long-Term Evolution (LTE2500) and 5.164GHz for Wireless Local Area Network (WLAN) applications. In the OFF state, the antenna operates at 5.302GHz, which is also suitable for WLAN application. The proposed antenna is fabricated on a FR-4 substrate with a relative dielectric constant, ε r of 4.5, thickness, h of 1.6mm and loss tangent, tan δ of 0.019. The fabrication process is carried out at the Advanced Printed Circuit Board (PCB) Design Laboratory in UTHM.
Miniature design of T-Shaped frequency Reconfigurable antenna for S-Band Appl...IJECEIAES
The article presents a miniature antenna with a simple geometry and a simple approach for reconfiguration. In order to make the T-shaped antenna frequency reconfigurable, we integrated Switches in specific positions. The location of the switches is determined following a study of the distribution of the surface currents of the suggested antenna. Indeed, we found that the insertion of switches in places where the concentrations of surface currents are high is irrelevant. In fact, to redirect current flow, the PIN diodes or RF Switch must be placed in positions where the distribution of the surface currents is of low concentration. These locations facilitate the establishment of new trajectories of the flux of current. As a result, a miniature tunable antenna dimension 20mm*20mm*1.6mm printed on FR4 substrate with 4.4 permittivity and with 0.04 loss tangent, the antenna can be adopted in many communication devices in view of its small size, its low manufacturing cost and performance on frequency sweep, the antenna operates in S-Band with an acceptable band and gain. The antenna is simulated and optimized using CST Microwave Studio.
Designing an Antenna System That Can Perform Conditional RF to DC Harnessing ...IOSRJECE
Electromagnetic energy or RF energy will play a pivotal role in wireless technology and wireless communication in the impending future. The paper proposes a concept for a patch antenna based system that can harness RF energy upon triggering and can convert the harnessed RF to DC from the radio frequency of 1 GHz to 3 GHz, the design frequency is 2.4GHz. The patch antenna system contains a high gain patch antenna along with a wireless communicating module and a conversion circuit. The return loss of the antenna is approximately 27.1dB. The power gain is 30.1 dBm .The converter circuit is designed in), Multi-Sim to get an output voltage of around 5V that can be used to power a mobile-device or maybe stored in a battery. The triggering part is done with the help of a T-mote which is simulated in a network simulator, Cooja. The patch antenna is simulated in High Frequency Structural Simulator
Compact reconfigurable PIFA antenna for wireless applicationsTELKOMNIKA JOURNAL
This paper presents, new compact and multiband frequency reconfigurable planar inverted-F antenna (PIFA). The antenna is designed and optimized to cover mobile application devices like GPS, WLAN/Wi-Fi, WiMAX, 4G LTE, UWB, and satellite applications. The frequency reconfigurability is obtained by using only a single RF switch (PIN diode) for changing the operating frequency. The antenna dimensions are 45.6x39.6x1.6 mm3 printed on an FR-4 epoxy substrate with relative dielectric constant εr = 4.3, loss tangent tan (δ) = 0.002 and 50 Ω coaxial feed line. The proposed antenna has two patches connected by a single PIN diode. The antenna introduces nine resonant frequencies under (S11 ≤ -10 dB) which are: 0.980 GHz, 3.392 GHz, 3.924 GHz, 4.554 GHz, 5.82 GHz, 6.81 GHz, 7.305 GHz, 8 GHz and 8.105 GHz in the ON and OFF states of the PIN diode which are applicable to cover GSM900, WLAN/Wi-Fi, WiMAX, 4G LTE, UWB, and satellite systems. The obtained maximum simulated gain is 8.45 dB at 6.81 GHz. The lowest return loss is obtained to be -42 dB at 5.854 GHz. Detailed simulation and measurement results are explored and studied in this research. The CST software is used to simulate and optimize the proposed PIFA antenna. The proposed antenna has been fabricated and produced a good agreement with the simulation results.
Circularly polarized antenna array based on hybrid couplers for 5G devicesjournalBEEI
This paper depicts a wideband circularly polarized (CP) antenna for 5G devices. The antenna array has a 3D structure including four simple printed dipole elements with directional radiations, high gain, and high efficiency. It achieves a CP by using the sequential rotation (SR) feeding based on 90°-3dB hybrid couplers in the proposed feeding network. The antenna array bandwidth is wide, 26.7%, with an operating frequency band from 3.35 GHz to 4.35 GHz. The antenna achieves a high peak gain of 10.73 dBi and high efficiency of 93.75%. Besides, the antenna gain is stable over the operating bandwidth (BW). At the centre operating frequency of 3.75 GHz, the angle of circular polarization is 51°. The antenna is designed and fabricated on the Rogers 4003 C substrate. The measured S11 is well matching with the simulation results. With the above characteristics, the proposed antenna can be a suitable candidate for 5G devices.
In this research paper, substrate integrated waveguide (SIW) was proposed as a technique by
realizing bilateral edge walls to produce a compact 5G beam-steering antenna at 24 GHz. The beam
forming network is produced using SIW directional coupler perform as 2×2 Butler Matrix (BM) fed with SIW
slotted waveguide antenna array. The output signal is steered from -29 degrees and +29 degrees when
the signal is fed to the respective input ports. If one of the input ports is fed, the signal is evenly distributed
between the adjacent output ports with 90 degree constant phase shift. The compact size of directional
coupler was designed by longitude slots on the surface of SIW substrate with bandwith of 16.85% at the
operating frequency. The proposed antenna produce gain of 6.34 dB at operating frequency and the
promising outcome of the beam steering make proposed design suitable for 5G communications especially
with tracking capabilities.
Simulation and optimization of tuneable microstrip patch antenna for fifth-ge...IJECEIAES
Microstrip patch antennas (MPAs) are known largely for their versatility in terms of feasible geometries, making them applicable in many distinct circumstances. In this paper, a graphene-based tuneable single/array rectangular microstrip patch antenna (MPA) utilizing an inset feed technique designed to function in multiple frequency bands are used in a fifth-generation (5G) wireless communications system. The tuneable antenna is used to eliminate the difficulties caused by the narrow bandwidths typically associated with MPAs. The graphene material has a reconfigurable surface conductivity that can be adjusted to function at the required value, thus allowing the required resonance frequency to be selected. The simulated tuneable antenna comprises a copper radiating patch with four graphene strips used for tuning purposes and is designed to cover a wide frequency band. The proposed antenna can be tuned directly by applying a direct current (DC) voltage to the graphene strips, resulting in a variation in the surface impedance of the graphene strips and leading to shifts in the resonance frequency.
Outage performance users located outside D2D coverage area in downlink cellul...journalBEEI
Device-to-device (D2D) communication has been proposed to employ the proximity between two devices to enhance the overall spectrum utilization of a crowded cellular network. With the help of geometric probability tools, this framework considers the performance of cellular users under spatial separation with the D2D pair is investigated. The measurement results and analytical expression of outage probability show that the proposed frameworks improve the outage performance at a high signal-tonoise ratio (SNR) at the base station. Results also interpret that the distances between nodes in the D2D-assisted network make slight impacts on the performance of the cellular user.
PERFORMANCE ANALYSIS OF 2D-EBG UNDER MONOPOLE ANTENNAjantjournal
The artificial properties in two dimensional electromagnetic structures (2D-EBGs), such as PMC and Band Reject Region are investigated for a proposed structure of square shaped mushroom. The radiation characteristics of monopole antenna over this 2D-EBG is tested by considering two cases. During first case monopole antenna is made to operate within band rejection region. Second case monopole antenna made operate outside the band rejection range. The obtained results during first case is showing enhancement in operating band width and smoother radiation pattern. In second case the effect is null and
2D-EBG resembles like conventional plane reflector. The simulated results are presented.
Design and Implementation of Re-configurable AntennaIJARIIT
This paper introduces a design of advanced and efficient technique used for antenna reconfiguration. Conventional
antennas are designed for specific application as it operates at a particular frequency range. On the other hand reconfigurable
antenna provides performance enhancement and gives single antenna structure to operate at various frequency range. In
order to obtain this, we use the technique of frequency reconfiguration i.e. PIN diode switching through which it can switch
among different frequency band. Antenna design is simulated and analyzed using HFSS software.
A Novel Design of a Microstrip Microwave Power Amplifier for DCS Application ...IJECEIAES
This paper presents a 1.80GHz class-A Microwave power amplifier (PA). The proposed power amplifier is designed with single-stage architecture. This power amplifier consists of a bipolar transistor and improved by Collector-Feedback Biasing fed with a single power supply. The aim of this work is to improve the performance of this amplifier by using simple stubs with 50Ω microstrip transmissions lines. The proposed PA is investigated and optimized by utilizing Advanced Design System (ADS) software. The simulation results show that the amplifier achieves a high power gain of 13dB, output power rise up to 21dBm and good impedances matching ;For the input reflection coefficient (S11) is below than - 46.39dB. Regarding the output reflection coefficient (S22) is below than -29.898dB, with an overall size of about 93 x 59mm². By the end; we find that this power amplifier offers an excellent performance for DCS applications.
Designing large-scale antenna array using sub-arrayjournalBEEI
Antenna array of large scale have been examined for different applications including 5G technology. To get better data rate or a reliable link substantial number of antenna arrays have been utilized to provide high multiplexing gains as well as array gains with high directivity. In this paper a simple but efficient implementation technique of using sub-arrays for the improvement of large-sized uniform arrays. By repeating a small sub-array multiple times large arrays can be designed. This implication of utilizing small array simplifies the design of a larger array which allows the designer to concentrate on the smaller sub-array before assembling larger arrays. So, by investigating the sub arrays the performance and radiation characteristics of large arrays can be anticipated. The array-factor for a planar sub-array of 2x2 (4 elements) is analyzed using Mat-lab software and then a large array is formed by placing the 2x2 sub-array indifferent configurations in a rectangular arrangements up to 8x8 planar array. And then the results are validated with CST (Computer simulation technology) simulation results.In this way the array-factors, directivities, HPBWs, and side lobes of the constructed large arrays are analyzed and associated with the small sub-array.
An Internal Wideband Monopole Antenna for UMTS/WLAN Dual-Mode Mobile PhoneSaou-Wen Su
An internal wideband metal-plate monopole antenna for mobile phone applications is presented. The antenna is easily fabricated by bending a single metal plate and suitable to be embedded within the casing of a mobile phone as an internal antenna. Further, the antenna shows a wide operating bandwidth of about 5 GHz (about 1.8−6.7 GHz), making it easy to cover the UMTS band and the 2.4/5.2/5.8 GHz WLAN bands for mobile/WLAN dual-mode operation for a mobile phone.
A NEW MODIFIED SYSTEM FOR EQUAL POWER DIVISION WITH LCC FOR WIRELESS APPLCATIONSijistjournal
In this paper, a new modified system for equal power division is implemented with the help of rectangular micro strip patch antenna, Gysel power divider and leakage cancellation circuit. Today’s world power division plays an important role in wireless application areas such as base stations, antenna arrays, handheld devices etc., Here micro strip patch antenna is implemented with FR4 as a substrate material due to its benefits such as low loss and low fabrication cost while the ground material is aluminium due to its conductivity. For a good system, the return loss should be highly desirable and insertion loss should be low. Our proposed system is designed with a combination of micro strip patch antenna, leakage cancellation circuit and Gysel power divider produces equal power division with low loss such as insertion loss is measured as -39.291dB, return loss as -16.11dB and leakage cancellation as 6dB which was designed and simulated in Agilent Advanced Design System software (2009).
Simulation and optimization of a tuneable rectangular microstrip patch antenn...TELKOMNIKA JOURNAL
In this paper, a tuneable rectangular microstrip patch antenna (MPA) is simulated and optimized to operate in four frequency bands of the next generation of wireless communication systems. The proposed design incorporates a copper radiating patch with four implanted graphene strips for tuning purposes. The reconfigurable surface impedance of graphene can easily be altered by applying a DC voltage bias directly to the graphene strips, allowing the operating frequency of the antenna to be tuned as desired. The capability of the applied voltage to tune the operating frequency band of the proposed antenna is studied via computer simulation technology (CST) microwave studio (MWS). Frequency selective surfaces (FSSs) are introduced in order to improve the radiation parameters of the antenna. The operating frequency band of the tuneable rectangular MPA increases directly as the applied DC voltage bias is increased. Based on the simulation results, a tuneable rectangular MPA placed between two FSSs is proposed for fifth-generation applications.
Electrically Controlled Frequency Reconfigurable Comb Type Antenna for Wirele...IDES Editor
Electrically controlled frequency reconfigurable
comb type antenna is presented in this paper. Reconfigurability
is achieved by placing a PIN diode in each slot of the comb
type antenna. The proposed antenna has very compact size
and works on 8 different bands depending upon the state and
number of PIN diode (ON/OFF). Ansoft Designer 7 is used to
simulate the equivalent model for the PIN diode and proposed
antenna is fabricated on FR4 substrate using photolithography
process. As the antenna reconfigure its resonating frequency
from 1st band to 8th band, directivity increases from 3.28 to 4.02
and radiation efficiency increases from 75.3% to 93.45% due
to the improvement in impedance matching at higher band.
Design and characterization of frequency reconfigurable honey bee antenna fo...IJECEIAES
In this article, a frequency reconfigurable honey-bee compact microstrip monopole antenna is proposed which is fed by a microstrip line (50 Ω) having the capability of providing dual-band as well as triple-band operation in eight distinct modes. By embedding three PIN diodes overs the honey bee arms, the effective current distribution is controlled hence resonant frequency is also changed in eight distinct modes in real-time. This is the reason the proposed antenna is portrayed as a frequency reconfigurable antenna in this paper which is suitable for cognitive radio application. This proposed antenna can be used for various wireless application such as Bluetooth, Wi-Fi, worldwide interoperability for microwave access (WiMAX), wireless local area network (WLAN), C-band, and X-band applications. The proposed antenna possesses a planner geometry of 39×34×0.87 mm3 which is printed on a substrate as flexible FR-4 (lossy) (εr=4.4 and tanδ=0.019). The proposed antenna exhibits voltage standing wave ratio (VSWR)<2 for all 19 resonant frequencies of interest and perceptible radiation pattern over entire frequency bands with a positive gain. CST microwave studio is used to find out all simulated results of antenna parameters.
In this research paper, substrate integrated waveguide (SIW) was proposed as a technique by
realizing bilateral edge walls to produce a compact 5G beam-steering antenna at 24 GHz. The beam
forming network is produced using SIW directional coupler perform as 2×2 Butler Matrix (BM) fed with SIW
slotted waveguide antenna array. The output signal is steered from -29 degrees and +29 degrees when
the signal is fed to the respective input ports. If one of the input ports is fed, the signal is evenly distributed
between the adjacent output ports with 90 degree constant phase shift. The compact size of directional
coupler was designed by longitude slots on the surface of SIW substrate with bandwith of 16.85% at the
operating frequency. The proposed antenna produce gain of 6.34 dB at operating frequency and the
promising outcome of the beam steering make proposed design suitable for 5G communications especially
with tracking capabilities.
Simulation and optimization of tuneable microstrip patch antenna for fifth-ge...IJECEIAES
Microstrip patch antennas (MPAs) are known largely for their versatility in terms of feasible geometries, making them applicable in many distinct circumstances. In this paper, a graphene-based tuneable single/array rectangular microstrip patch antenna (MPA) utilizing an inset feed technique designed to function in multiple frequency bands are used in a fifth-generation (5G) wireless communications system. The tuneable antenna is used to eliminate the difficulties caused by the narrow bandwidths typically associated with MPAs. The graphene material has a reconfigurable surface conductivity that can be adjusted to function at the required value, thus allowing the required resonance frequency to be selected. The simulated tuneable antenna comprises a copper radiating patch with four graphene strips used for tuning purposes and is designed to cover a wide frequency band. The proposed antenna can be tuned directly by applying a direct current (DC) voltage to the graphene strips, resulting in a variation in the surface impedance of the graphene strips and leading to shifts in the resonance frequency.
Outage performance users located outside D2D coverage area in downlink cellul...journalBEEI
Device-to-device (D2D) communication has been proposed to employ the proximity between two devices to enhance the overall spectrum utilization of a crowded cellular network. With the help of geometric probability tools, this framework considers the performance of cellular users under spatial separation with the D2D pair is investigated. The measurement results and analytical expression of outage probability show that the proposed frameworks improve the outage performance at a high signal-tonoise ratio (SNR) at the base station. Results also interpret that the distances between nodes in the D2D-assisted network make slight impacts on the performance of the cellular user.
PERFORMANCE ANALYSIS OF 2D-EBG UNDER MONOPOLE ANTENNAjantjournal
The artificial properties in two dimensional electromagnetic structures (2D-EBGs), such as PMC and Band Reject Region are investigated for a proposed structure of square shaped mushroom. The radiation characteristics of monopole antenna over this 2D-EBG is tested by considering two cases. During first case monopole antenna is made to operate within band rejection region. Second case monopole antenna made operate outside the band rejection range. The obtained results during first case is showing enhancement in operating band width and smoother radiation pattern. In second case the effect is null and
2D-EBG resembles like conventional plane reflector. The simulated results are presented.
Design and Implementation of Re-configurable AntennaIJARIIT
This paper introduces a design of advanced and efficient technique used for antenna reconfiguration. Conventional
antennas are designed for specific application as it operates at a particular frequency range. On the other hand reconfigurable
antenna provides performance enhancement and gives single antenna structure to operate at various frequency range. In
order to obtain this, we use the technique of frequency reconfiguration i.e. PIN diode switching through which it can switch
among different frequency band. Antenna design is simulated and analyzed using HFSS software.
A Novel Design of a Microstrip Microwave Power Amplifier for DCS Application ...IJECEIAES
This paper presents a 1.80GHz class-A Microwave power amplifier (PA). The proposed power amplifier is designed with single-stage architecture. This power amplifier consists of a bipolar transistor and improved by Collector-Feedback Biasing fed with a single power supply. The aim of this work is to improve the performance of this amplifier by using simple stubs with 50Ω microstrip transmissions lines. The proposed PA is investigated and optimized by utilizing Advanced Design System (ADS) software. The simulation results show that the amplifier achieves a high power gain of 13dB, output power rise up to 21dBm and good impedances matching ;For the input reflection coefficient (S11) is below than - 46.39dB. Regarding the output reflection coefficient (S22) is below than -29.898dB, with an overall size of about 93 x 59mm². By the end; we find that this power amplifier offers an excellent performance for DCS applications.
Designing large-scale antenna array using sub-arrayjournalBEEI
Antenna array of large scale have been examined for different applications including 5G technology. To get better data rate or a reliable link substantial number of antenna arrays have been utilized to provide high multiplexing gains as well as array gains with high directivity. In this paper a simple but efficient implementation technique of using sub-arrays for the improvement of large-sized uniform arrays. By repeating a small sub-array multiple times large arrays can be designed. This implication of utilizing small array simplifies the design of a larger array which allows the designer to concentrate on the smaller sub-array before assembling larger arrays. So, by investigating the sub arrays the performance and radiation characteristics of large arrays can be anticipated. The array-factor for a planar sub-array of 2x2 (4 elements) is analyzed using Mat-lab software and then a large array is formed by placing the 2x2 sub-array indifferent configurations in a rectangular arrangements up to 8x8 planar array. And then the results are validated with CST (Computer simulation technology) simulation results.In this way the array-factors, directivities, HPBWs, and side lobes of the constructed large arrays are analyzed and associated with the small sub-array.
An Internal Wideband Monopole Antenna for UMTS/WLAN Dual-Mode Mobile PhoneSaou-Wen Su
An internal wideband metal-plate monopole antenna for mobile phone applications is presented. The antenna is easily fabricated by bending a single metal plate and suitable to be embedded within the casing of a mobile phone as an internal antenna. Further, the antenna shows a wide operating bandwidth of about 5 GHz (about 1.8−6.7 GHz), making it easy to cover the UMTS band and the 2.4/5.2/5.8 GHz WLAN bands for mobile/WLAN dual-mode operation for a mobile phone.
A NEW MODIFIED SYSTEM FOR EQUAL POWER DIVISION WITH LCC FOR WIRELESS APPLCATIONSijistjournal
In this paper, a new modified system for equal power division is implemented with the help of rectangular micro strip patch antenna, Gysel power divider and leakage cancellation circuit. Today’s world power division plays an important role in wireless application areas such as base stations, antenna arrays, handheld devices etc., Here micro strip patch antenna is implemented with FR4 as a substrate material due to its benefits such as low loss and low fabrication cost while the ground material is aluminium due to its conductivity. For a good system, the return loss should be highly desirable and insertion loss should be low. Our proposed system is designed with a combination of micro strip patch antenna, leakage cancellation circuit and Gysel power divider produces equal power division with low loss such as insertion loss is measured as -39.291dB, return loss as -16.11dB and leakage cancellation as 6dB which was designed and simulated in Agilent Advanced Design System software (2009).
Simulation and optimization of a tuneable rectangular microstrip patch antenn...TELKOMNIKA JOURNAL
In this paper, a tuneable rectangular microstrip patch antenna (MPA) is simulated and optimized to operate in four frequency bands of the next generation of wireless communication systems. The proposed design incorporates a copper radiating patch with four implanted graphene strips for tuning purposes. The reconfigurable surface impedance of graphene can easily be altered by applying a DC voltage bias directly to the graphene strips, allowing the operating frequency of the antenna to be tuned as desired. The capability of the applied voltage to tune the operating frequency band of the proposed antenna is studied via computer simulation technology (CST) microwave studio (MWS). Frequency selective surfaces (FSSs) are introduced in order to improve the radiation parameters of the antenna. The operating frequency band of the tuneable rectangular MPA increases directly as the applied DC voltage bias is increased. Based on the simulation results, a tuneable rectangular MPA placed between two FSSs is proposed for fifth-generation applications.
Electrically Controlled Frequency Reconfigurable Comb Type Antenna for Wirele...IDES Editor
Electrically controlled frequency reconfigurable
comb type antenna is presented in this paper. Reconfigurability
is achieved by placing a PIN diode in each slot of the comb
type antenna. The proposed antenna has very compact size
and works on 8 different bands depending upon the state and
number of PIN diode (ON/OFF). Ansoft Designer 7 is used to
simulate the equivalent model for the PIN diode and proposed
antenna is fabricated on FR4 substrate using photolithography
process. As the antenna reconfigure its resonating frequency
from 1st band to 8th band, directivity increases from 3.28 to 4.02
and radiation efficiency increases from 75.3% to 93.45% due
to the improvement in impedance matching at higher band.
Design and characterization of frequency reconfigurable honey bee antenna fo...IJECEIAES
In this article, a frequency reconfigurable honey-bee compact microstrip monopole antenna is proposed which is fed by a microstrip line (50 Ω) having the capability of providing dual-band as well as triple-band operation in eight distinct modes. By embedding three PIN diodes overs the honey bee arms, the effective current distribution is controlled hence resonant frequency is also changed in eight distinct modes in real-time. This is the reason the proposed antenna is portrayed as a frequency reconfigurable antenna in this paper which is suitable for cognitive radio application. This proposed antenna can be used for various wireless application such as Bluetooth, Wi-Fi, worldwide interoperability for microwave access (WiMAX), wireless local area network (WLAN), C-band, and X-band applications. The proposed antenna possesses a planner geometry of 39×34×0.87 mm3 which is printed on a substrate as flexible FR-4 (lossy) (εr=4.4 and tanδ=0.019). The proposed antenna exhibits voltage standing wave ratio (VSWR)<2 for all 19 resonant frequencies of interest and perceptible radiation pattern over entire frequency bands with a positive gain. CST microwave studio is used to find out all simulated results of antenna parameters.
A new configuration of patch antenna array for rectenna array applicationsTELKOMNIKA JOURNAL
The performance and advantages of microstrip patch antennas made them a field of interest for wireless power transmission applications, especially for rectenna systems where the choice of the antenna is a crucial step. In this paper, a 5.8 GHz circularly polarized patch antenna has been designed and fabricated, then mounted by using 4 elements to achieve an antenna array to enhance the captured power to be converted by the rectifier circuit. The antenna array is well matched at 5.8 GHz in terms of reflection coefficient and has a directivity of 11 dB and a gain of 6 dB. Results have been confirmed by fabrication.
Architecture of an efficient dual band 1.8/2.5 GHz rectenna for RF energy har...TELKOMNIKA JOURNAL
This paper presents a highly efficient rectenna of RF energy harvesting systems operating at
1.8 GHz and 2.5 GHz bands for battery-less sensor application. The antenna is design by CST-MWS.
The Schottky diode used for rectifying circuit is HSMS 286B in which designed by Agilent ADS. The key
finding of the paper is that the simulated DC output voltage of the rectenna is 1.35 V for low input power of
-25 dBm at a high resistance load of 1M Ω. Correspondingly, the RF-DC conversion efficiency of
the rectification process is 59.51% and 45.75% at 1.8 GHz and 2.5 GHz, which are high efficiency and much
better compared to literature respectively. The rectenna is capable to produce 1.8 V from an input power of
-20 dBm. Thus, the proposed RF energy harvesting system offers a promising solution designed for efficient
functionality at a low power level of RF energy in the dual band.
A simple design and fabrication of polarization reconfigurable antenna for in...IJECEIAES
This paper proposes a simple microstrip patch antenna (MPA) that can reconfigure its polarization states from linear to circular polarization in real-time by means of a PIN diode. An antenna is fed by a 50 Ω coaxial cable through the substrate of Teflon with relative permittivity of 2.15. The proposed antenna possesses a simple patch with a one-sided corner truncated to achieve polarization reconfigurability. A PIN diode is loaded to connect the main patch with a truncated corner and further maintain dual polarization states such as linear polarization (LP) and circular polarization (CP). Advanced design system (ADS) was used as a simulator to simulate the antenna, and a good understanding was obtained between simulated and measured results. Measured results showed a good agreement with simulated results at all working frequencies of interest. It shows minimum reflection coefficient gain with -10 dB scattering bandwidth 100 MHz for LP states and 170 MHz for CP states. It also shows an axial ratio of 1.56 dB for CP, and the cross-polarization level is also in a satisfying range.
Two, four, eight, and sixteen-element patch array antennas for beam switching are presented in this study. For a 1×2 array, an aperture-coupled feeding mechanism is used to feed patches while a slot line on the ground plane provides the phase delay between antenna elements. The 1×2 array is used to create the 2×2, 4×2, and 8×2 arrays, and an equal power divider provides the signal for each. For applications in the 5G sub-6 GHz frequency spectrum, the antennas are modeled. With -37.14 dB, -17.85 dB, -21.51 dB, and -26.03 dB return loss for two, four, eight, and sixteen-element array antennas respectively the simulation demonstrates that the antennas are properly matched at the resonant frequency. The antennas can switch its radiated beam to ±24 ◦ , ±24 ◦ , ◦ ±28 , and ±26 ◦ with gains of 8.97 dBi, 11.19 dBi, 13.23 dBi, and 16.24 dBi, respectively at the resonance frequency. The directivity of the proposed antenna is found to be 9.17 dBi, 11.20 dBi, 13.40 dBi, and 16.45 dBi respectively. The antennas are constructed with two 0.8 mm-thick Teflon substrate layers. The ground plane between the two substrate layers contains the aperture and the slot line that generates the phase delay.
Frequency reconfigurable rectangular patch antenna for cognitive radio appli...IJECEIAES
A frequency reconfigurable microstrip transformed rectangular patch antenna consisting of two slots able to radiate in S-band and C-band is proposed. Spectrum occupancy is first analyzed using the data from literature and internet sources and hence spectrum holes are identified. A rectangular radiating patch is then designed for 5.8 GHz resonant frequency. A coaxial feed is used in the bottom by a suitable feed point. Two slots at an angle of +45 degree are made at the two corners. The electrical length of the patch is changed by using two varactor diodes in the slots. The varactors enable frequency reconfiguration in the band of frequencies that are unused or the spectral occupancy is very less. The return loss, voltage standing wave ratio (VSWR), and 2D-radiation patterns are analyzed for various values of the capacitances. high-frequency structure simulator (HFSS) is used for simulation. FR4 substrate which is economical, is used with height, h=1.6 mm, width W=25.33 mm, and length L=21.34 mm. On the substrate the rectangular patch is of width 15.73 mm and length 11.74 mm. The return loss and radiation patterns for different values of capacitances is presented. The tunability ratio obtained is 1.93. The results obtained agree with the standards.
Octa-band reconfigurable monopole antenna frequency diversity 5G wirelessIJECEIAES
An octa-band frequency-reconfigurable antenna (28×14×1.5 mm 3 ) with a broad tuning range is shown. Antenna mode1 (4.31 GHz) works in one single-band mode and two dual-band in modes 2 and 3 (i.e., 3.91 and 5.9 GHz) as well as one tri-band in mode 4 (i.e., 3.09, 5.65, and 7.92 GHz) based on the switching situation of the antenna. Changing capacitance for frequency reconfigurability is accomplished with the use of lumped components. The antenna’s observed tuning spans from 3.09 GHz to 7.92 GHz. for all the resonant bands, the suggested antenna has a voltage standing waves ratio (VSWR)<1.45 except for one band with a VSWR<1.85. From 70.57% to 97.93%, the suggested structure’s radiation efficiency may be calculated. For a better understanding proposed antenna’s far field and scattering characteristics, we used CST Microwave Studio 2021. We may conclude that our suggested antenna is suitable for today’s wireless applications, which need multiband and multimode small antennas. Using a small stainless-steel wire as a switch, a prototype of the antenna design is built and tested to verify the simulation findings. The suggested reconfigurable antenna’s strong concordance between simulated and measured findings.
A new design of a microstrip rectenna at 5.8 GHz for wireless power transmiss...IJECEIAES
Due to the ever-increasing power demand, the need of electricity and eco-friendly power in every nook and corner of the world, many reaserch topics have been devoted to deal with this problematic. This paper is taking part of the proposed solutions with the presentation of a novel 5.8 GHz rectenna system for wireless power transmission applications. In one hand, a miniaturized 5.8 GHz circular polarized patch antenna has been designed and simulated by using the Advanced Design System (ADS). In the other hand, a rectifier structure has been investigated and optimized by the use of the Harmonic Balance method available in ADS. The circuit is based on 5 HSMS2820 Schottky diodes implemented in a voltage multiplier topology and a load resistance of 1 KOhm. Both of the structures have been validated by simulation and experimental results and good agreement has been concluded.
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.
Radiation beam scanning for leaky wave antenna by using slotsTELKOMNIKA JOURNAL
This paper provides an insight of a new, microstrip leaky wave antenna. It holds the ability to continue steer its beam at a swapping frequency. This is done with acceptable impedance matching while scanning and very little gain variation. Investigation is carried out on LWAs’ control radiation pattern in steps at a band frequency via vertical and horizontal slots. The enhancement is realized by etching horizontal and vertical slots on the radiation element. This study also presents a novel half-width microstrip leaky wave antenna (LWA). The antenna is made up of the following basic structures group’s vertical and horizontal slots. The reactance profile at the microstrip’s free edge and thus the main beam direction is changed once the control-cell states are changed. The radiation pattern direction changes by sweeping the operating frequency between 4 GHz to 6 GHz.The main beam may be directed by the antenna between 15o and 55o. C band achieved the measured peak gain of the antenna of 10 dBi at 4.3 GHz beam scanning range.
The implementations of the microstrip patch antenna for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) are analyzed in the literature in this research. Dual or multiband antenna has played a significant part in meeting the expectations of wireless service in this quickly developing world of wireless communication. Basically, a transitory guide, an antenna is a device that emits or absorbs radio waves. Numerous benefits exist for microstrip patch antennas, including affordability, portability, simplicity of construction, and compatibility with integrated circuits. This has several important uses in the military, radar, mobile communications, global positioning system (GPS), remote sensing, and more. In mobile devices like portable computers and smartphones, WLAN and WiMAX are often used.
PROJECT DESCRIPTION
DOWNLOAD
The main objective of this project is to develop a device for wireless power transfer. The concept of wireless power transfer was realized by Nikolas tesla. Wireless power transfer can make a remarkable change in the field of the electrical engineering which eliminates the use conventional copper cables and current carrying wires.
Based on this concept, the project is developed to transfer power within a small range. This project can be used for charging batteries those are physically not possible to be connected electrically such as pace makers (An electronic device that works in place of a defective heart valve) implanted in the body that runs on a battery.
The patient is required to be operated every year to replace the battery. This project is designed to charge a rechargeable battery wirelessly for the purpose. Since charging of the battery is not possible to be demonstrated, we are providing a DC fan that runs through wireless power.
This project is built upon using an electronic circuit which converts AC 230V 50Hz to AC 12V, High frequency. The output is fed to a tuned coil forming as primary of an air core transformer. The secondary coil develops a voltage of HF 12volt.
Thus the transfer of power is done by the primary(transmitter) to the secondary that is separated with a considerable distance(say 3cm). Therefore the transfer could be seen as the primary transmits and the secondary receives the power to run load.
Moreover this technique can be used in number of applications, like to charge a mobile phone, iPod, laptop battery, propeller clock wirelessly. And also this kind of charging provides a far lower risk of electrical shock as it would be galvanically isolated.
A Novel Configuration of A Microstrip Power Amplifier based on GaAs-FET for I...IJECEIAES
Power Amplifiers (PA) are very indispensable components in the design of numerous types of communication transmitters employed in microwave technology. The methodology is exemplified through the design of a 2.45GHz microwave power Amplifier (PA) for the industrial, scientific and medical (ISM) applications using microstrip technology. The main design target is to get a maximum power gain while simultaneously achieving a maximum output power through presenting the optimum impedance which is characteristically carried out per adding a matching circuit between the source and the input of the power amplifier and between the load and the output of the power amplifier. A "T" matching technique is used at the input and the output sides of transistor for assure in band desired that this circuit without reflections and to obtain a maximum power gain. The proposed power amplifier for microwave ISM applications is designed, simulated and optimized by employing Advanced Design System (ADS) software by Agilent. The PA shows good performances in terms of return loss, output power, power gain and stability; the circuit has an input return loss of -38dB and an output return loss of -33.5dB. The 1-dB compression point is 8.69dBm and power gain of the PA is 19.4dBm. The Rollet's Stability measure B1 and the stability factor K of the amplifier is greater than 0 and 1 respectively, which shows that the circuit is unconditionally stable. The total chip size of the PA is 73.5× 36 mm 2 .
PROJECT DESCRIPTION
DOWNLOAD
The main objective of this project is to develop a device for wireless power transfer. The concept of wireless power transfer was realized by Nikolas tesla. Wireless power transfer can make a remarkable change in the field of the electrical engineering which eliminates the use conventional copper cables and current carrying wires.
Based on this concept, the project is developed to transfer power within a small range. This project can be used for charging batteries those are physically not possible to be connected electrically such as pace makers (An electronic device that works in place of a defective heart valve) implanted in the body that runs on a battery.
The patient is required to be operated every year to replace the battery. This project is designed to charge a rechargeable battery wirelessly for the purpose. Since charging of the battery is not possible to be demonstrated, we are providing a DC fan that runs through wireless power.
This project is built upon using an electronic circuit which converts AC 230V 50Hz to AC 12V, High frequency. The output is fed to a tuned coil forming as primary of an air core transformer. The secondary coil develops a voltage of HF 12volt.
Thus the transfer of power is done by the primary(transmitter) to the secondary that is separated with a considerable distance(say 3cm). Therefore the transfer could be seen as the primary transmits and the secondary receives the power to run load.
Moreover this technique can be used in number of applications, like to charge a mobile phone, iPod, laptop battery, propeller clock wirelessly. And also this kind of charging provides a far lower risk of electrical shock as it would be galvanically isolated.
Six-port Interferometer for W-band Transceivers: Design and CharacterizationIJECEIAES
The study has presented an extensive analysis of an integrated millimeter wave six-port interferometer, operating over a 10 GHz band, from 80 to 90 GHz. It has covered both semi-unlicensed point-to-point links (81-86 GHz), and imaging sensor system frequencies (above 85 GHz). An in-house process is used to fabricate miniaturized hybrid millimeter wave integrated circuits on a very thin ceramic substrate. Two-port S-parameter measurements are performed on a minimum number of circuits integrated on the same die, exploiting the circuit’s physical symmetry and chosen to collect enough data for full-port characterization. Based on these measurements on an integrated prototype, a six-port circuit computer model implemented and advanced system simulations performed for circuit analysis. Interferometer performances evaluated using several methods: analysis of harmonic balance, qi points’, homodyne quadrature demodulation, and error vector modulation (EVM). The analysis showed that this circuit can directly perform, without any calibration, the demodulation of various PSK and QAM signals over the 10 GHz band, with very good results.
International Refereed Journal of Engineering and Science (IRJES)irjes
International Refereed Journal of Engineering and Science (IRJES) is a leading international journal for publication of new ideas, the state of the art research results and fundamental advances in all aspects of Engineering and Science. IRJES is a open access, peer reviewed international journal with a primary objective to provide the academic community and industry for the submission of half of original research and applications
Similar to Reconfigurable ultra wideband to narrowband antenna for cognitive radio applications using PIN diode (20)
Amazon products reviews classification based on machine learning, deep learni...TELKOMNIKA JOURNAL
In recent times, the trend of online shopping through e-commerce stores and websites has grown to a huge extent. Whenever a product is purchased on an e-commerce platform, people leave their reviews about the product. These reviews are very helpful for the store owners and the product’s manufacturers for the betterment of their work process as well as product quality. An automated system is proposed in this work that operates on two datasets D1 and D2 obtained from Amazon. After certain preprocessing steps, N-gram and word embedding-based features are extracted using term frequency-inverse document frequency (TF-IDF), bag of words (BoW) and global vectors (GloVe), and Word2vec, respectively. Four machine learning (ML) models support vector machines (SVM), logistic regression (RF), logistic regression (LR), multinomial Naïve Bayes (MNB), two deep learning (DL) models convolutional neural network (CNN), long-short term memory (LSTM), and standalone bidirectional encoder representations (BERT) are used to classify reviews as either positive or negative. The results obtained by the standard ML, DL models and BERT are evaluated using certain performance evaluation measures. BERT turns out to be the best-performing model in the case of D1 with an accuracy of 90% on features derived by word embedding models while the CNN provides the best accuracy of 97% upon word embedding features in the case of D2. The proposed model shows better overall performance on D2 as compared to D1.
Design, simulation, and analysis of microstrip patch antenna for wireless app...TELKOMNIKA JOURNAL
In this study, a microstrip patch antenna that works at 3.6 GHz was built and tested to see how well it works. In this work, Rogers RT/Duroid 5880 has been used as the substrate material, with a dielectric permittivity of 2.2 and a thickness of 0.3451 mm; it serves as the base for the examined antenna. The computer simulation technology (CST) studio suite is utilized to show the recommended antenna design. The goal of this study was to get a more extensive transmission capacity, a lower voltage standing wave ratio (VSWR), and a lower return loss, but the main goal was to get a higher gain, directivity, and efficiency. After simulation, the return loss, gain, directivity, bandwidth, and efficiency of the supplied antenna are found to be -17.626 dB, 9.671 dBi, 9.924 dBi, 0.2 GHz, and 97.45%, respectively. Besides, the recreation uncovered that the transfer speed side-lobe level at phi was much better than those of the earlier works, at -28.8 dB, respectively. Thus, it makes a solid contender for remote innovation and more robust communication.
Design and simulation an optimal enhanced PI controller for congestion avoida...TELKOMNIKA JOURNAL
In this paper, snake optimization algorithm (SOA) is used to find the optimal gains of an enhanced controller for controlling congestion problem in computer networks. M-file and Simulink platform is adopted to evaluate the response of the active queue management (AQM) system, a comparison with two classical controllers is done, all tuned gains of controllers are obtained using SOA method and the fitness function chose to monitor the system performance is the integral time absolute error (ITAE). Transient analysis and robust analysis is used to show the proposed controller performance, two robustness tests are applied to the AQM system, one is done by varying the size of queue value in different period and the other test is done by changing the number of transmission control protocol (TCP) sessions with a value of ± 20% from its original value. The simulation results reflect a stable and robust behavior and best performance is appeared clearly to achieve the desired queue size without any noise or any transmission problems.
Improving the detection of intrusion in vehicular ad-hoc networks with modifi...TELKOMNIKA JOURNAL
Vehicular ad-hoc networks (VANETs) are wireless-equipped vehicles that form networks along the road. The security of this network has been a major challenge. The identity-based cryptosystem (IBC) previously used to secure the networks suffers from membership authentication security features. This paper focuses on improving the detection of intruders in VANETs with a modified identity-based cryptosystem (MIBC). The MIBC is developed using a non-singular elliptic curve with Lagrange interpolation. The public key of vehicles and roadside units on the network are derived from number plates and location identification numbers, respectively. Pseudo-identities are used to mask the real identity of users to preserve their privacy. The membership authentication mechanism ensures that only valid and authenticated members of the network are allowed to join the network. The performance of the MIBC is evaluated using intrusion detection ratio (IDR) and computation time (CT) and then validated with the existing IBC. The result obtained shows that the MIBC recorded an IDR of 99.3% against 94.3% obtained for the existing identity-based cryptosystem (EIBC) for 140 unregistered vehicles attempting to intrude on the network. The MIBC shows lower CT values of 1.17 ms against 1.70 ms for EIBC. The MIBC can be used to improve the security of VANETs.
Conceptual model of internet banking adoption with perceived risk and trust f...TELKOMNIKA JOURNAL
Understanding the primary factors of internet banking (IB) acceptance is critical for both banks and users; nevertheless, our knowledge of the role of users’ perceived risk and trust in IB adoption is limited. As a result, we develop a conceptual model by incorporating perceived risk and trust into the technology acceptance model (TAM) theory toward the IB. The proper research emphasized that the most essential component in explaining IB adoption behavior is behavioral intention to use IB adoption. TAM is helpful for figuring out how elements that affect IB adoption are connected to one another. According to previous literature on IB and the use of such technology in Iraq, one has to choose a theoretical foundation that may justify the acceptance of IB from the customer’s perspective. The conceptual model was therefore constructed using the TAM as a foundation. Furthermore, perceived risk and trust were added to the TAM dimensions as external factors. The key objective of this work was to extend the TAM to construct a conceptual model for IB adoption and to get sufficient theoretical support from the existing literature for the essential elements and their relationships in order to unearth new insights about factors responsible for IB adoption.
Efficient combined fuzzy logic and LMS algorithm for smart antennaTELKOMNIKA JOURNAL
The smart antennas are broadly used in wireless communication. The least mean square (LMS) algorithm is a procedure that is concerned in controlling the smart antenna pattern to accommodate specified requirements such as steering the beam toward the desired signal, in addition to placing the deep nulls in the direction of unwanted signals. The conventional LMS (C-LMS) has some drawbacks like slow convergence speed besides high steady state fluctuation error. To overcome these shortcomings, the present paper adopts an adaptive fuzzy control step size least mean square (FC-LMS) algorithm to adjust its step size. Computer simulation outcomes illustrate that the given model has fast convergence rate as well as low mean square error steady state.
Design and implementation of a LoRa-based system for warning of forest fireTELKOMNIKA JOURNAL
This paper presents the design and implementation of a forest fire monitoring and warning system based on long range (LoRa) technology, a novel ultra-low power consumption and long-range wireless communication technology for remote sensing applications. The proposed system includes a wireless sensor network that records environmental parameters such as temperature, humidity, wind speed, and carbon dioxide (CO2) concentration in the air, as well as taking infrared photos.The data collected at each sensor node will be transmitted to the gateway via LoRa wireless transmission. Data will be collected, processed, and uploaded to a cloud database at the gateway. An Android smartphone application that allows anyone to easily view the recorded data has been developed. When a fire is detected, the system will sound a siren and send a warning message to the responsible personnel, instructing them to take appropriate action. Experiments in Tram Chim Park, Vietnam, have been conducted to verify and evaluate the operation of the system.
Wavelet-based sensing technique in cognitive radio networkTELKOMNIKA JOURNAL
Cognitive radio is a smart radio that can change its transmitter parameter based on interaction with the environment in which it operates. The demand for frequency spectrum is growing due to a big data issue as many Internet of Things (IoT) devices are in the network. Based on previous research, most frequency spectrum was used, but some spectrums were not used, called spectrum hole. Energy detection is one of the spectrum sensing methods that has been frequently used since it is easy to use and does not require license users to have any prior signal understanding. But this technique is incapable of detecting at low signal-to-noise ratio (SNR) levels. Therefore, the wavelet-based sensing is proposed to overcome this issue and detect spectrum holes. The main objective of this work is to evaluate the performance of wavelet-based sensing and compare it with the energy detection technique. The findings show that the percentage of detection in wavelet-based sensing is 83% higher than energy detection performance. This result indicates that the wavelet-based sensing has higher precision in detection and the interference towards primary user can be decreased.
A novel compact dual-band bandstop filter with enhanced rejection bandsTELKOMNIKA JOURNAL
In this paper, we present the design of a new wide dual-band bandstop filter (DBBSF) using nonuniform transmission lines. The method used to design this filter is to replace conventional uniform transmission lines with nonuniform lines governed by a truncated Fourier series. Based on how impedances are profiled in the proposed DBBSF structure, the fractional bandwidths of the two 10 dB-down rejection bands are widened to 39.72% and 52.63%, respectively, and the physical size has been reduced compared to that of the filter with the uniform transmission lines. The results of the electromagnetic (EM) simulation support the obtained analytical response and show an improved frequency behavior.
Deep learning approach to DDoS attack with imbalanced data at the application...TELKOMNIKA JOURNAL
A distributed denial of service (DDoS) attack is where one or more computers attack or target a server computer, by flooding internet traffic to the server. As a result, the server cannot be accessed by legitimate users. A result of this attack causes enormous losses for a company because it can reduce the level of user trust, and reduce the company’s reputation to lose customers due to downtime. One of the services at the application layer that can be accessed by users is a web-based lightweight directory access protocol (LDAP) service that can provide safe and easy services to access directory applications. We used a deep learning approach to detect DDoS attacks on the CICDDoS 2019 dataset on a complex computer network at the application layer to get fast and accurate results for dealing with unbalanced data. Based on the results obtained, it is observed that DDoS attack detection using a deep learning approach on imbalanced data performs better when implemented using synthetic minority oversampling technique (SMOTE) method for binary classes. On the other hand, the proposed deep learning approach performs better for detecting DDoS attacks in multiclass when implemented using the adaptive synthetic (ADASYN) method.
The appearance of uncertainties and disturbances often effects the characteristics of either linear or nonlinear systems. Plus, the stabilization process may be deteriorated thus incurring a catastrophic effect to the system performance. As such, this manuscript addresses the concept of matching condition for the systems that are suffering from miss-match uncertainties and exogeneous disturbances. The perturbation towards the system at hand is assumed to be known and unbounded. To reach this outcome, uncertainties and their classifications are reviewed thoroughly. The structural matching condition is proposed and tabulated in the proposition 1. Two types of mathematical expressions are presented to distinguish the system with matched uncertainty and the system with miss-matched uncertainty. Lastly, two-dimensional numerical expressions are provided to practice the proposed proposition. The outcome shows that matching condition has the ability to change the system to a design-friendly model for asymptotic stabilization.
Implementation of FinFET technology based low power 4×4 Wallace tree multipli...TELKOMNIKA JOURNAL
Many systems, including digital signal processors, finite impulse response (FIR) filters, application-specific integrated circuits, and microprocessors, use multipliers. The demand for low power multipliers is gradually rising day by day in the current technological trend. In this study, we describe a 4×4 Wallace multiplier based on a carry select adder (CSA) that uses less power and has a better power delay product than existing multipliers. HSPICE tool at 16 nm technology is used to simulate the results. In comparison to the traditional CSA-based multiplier, which has a power consumption of 1.7 µW and power delay product (PDP) of 57.3 fJ, the results demonstrate that the Wallace multiplier design employing CSA with first zero finding logic (FZF) logic has the lowest power consumption of 1.4 µW and PDP of 27.5 fJ.
Evaluation of the weighted-overlap add model with massive MIMO in a 5G systemTELKOMNIKA JOURNAL
The flaw in 5G orthogonal frequency division multiplexing (OFDM) becomes apparent in high-speed situations. Because the doppler effect causes frequency shifts, the orthogonality of OFDM subcarriers is broken, lowering both their bit error rate (BER) and throughput output. As part of this research, we use a novel design that combines massive multiple input multiple output (MIMO) and weighted overlap and add (WOLA) to improve the performance of 5G systems. To determine which design is superior, throughput and BER are calculated for both the proposed design and OFDM. The results of the improved system show a massive improvement in performance ver the conventional system and significant improvements with massive MIMO, including the best throughput and BER. When compared to conventional systems, the improved system has a throughput that is around 22% higher and the best performance in terms of BER, but it still has around 25% less error than OFDM.
Reflector antenna design in different frequencies using frequency selective s...TELKOMNIKA JOURNAL
In this study, it is aimed to obtain two different asymmetric radiation patterns obtained from antennas in the shape of the cross-section of a parabolic reflector (fan blade type antennas) and antennas with cosecant-square radiation characteristics at two different frequencies from a single antenna. For this purpose, firstly, a fan blade type antenna design will be made, and then the reflective surface of this antenna will be completed to the shape of the reflective surface of the antenna with the cosecant-square radiation characteristic with the frequency selective surface designed to provide the characteristics suitable for the purpose. The frequency selective surface designed and it provides the perfect transmission as possible at 4 GHz operating frequency, while it will act as a band-quenching filter for electromagnetic waves at 5 GHz operating frequency and will be a reflective surface. Thanks to this frequency selective surface to be used as a reflective surface in the antenna, a fan blade type radiation characteristic at 4 GHz operating frequency will be obtained, while a cosecant-square radiation characteristic at 5 GHz operating frequency will be obtained.
Reagentless iron detection in water based on unclad fiber optical sensorTELKOMNIKA JOURNAL
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Impact of CuS counter electrode calcination temperature on quantum dot sensit...TELKOMNIKA JOURNAL
In place of the commercial Pt electrode used in quantum sensitized solar cells, the low-cost CuS cathode is created using electrophoresis. High resolution scanning electron microscopy and X-ray diffraction were used to analyze the structure and morphology of structural cubic samples with diameters ranging from 40 nm to 200 nm. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 °C, 120 °C, 150 °C, and 180 °C under vacuum. The fluorine doped tin oxide (FTO)/CuS cathode electrode reached a maximum efficiency of 3.89% when it was calcined at 120 °C. Compared to other temperature combinations, CuS nanoparticles crystallize at 120 °C, which lowers resistance while increasing electron lifetime.
In place of the commercial Pt electrode used in quantum sensitized solar cells, the low-cost CuS cathode is created using electrophoresis. High resolution scanning electron microscopy and X-ray diffraction were used to analyze the structure and morphology of structural cubic samples with diameters ranging from 40 nm to 200 nm. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 °C, 120 °C, 150 °C, and 180 °C under vacuum. The fluorine doped tin oxide (FTO)/CuS cathode electrode reached a maximum efficiency of 3.89% when it was calcined at 120 °C. Compared to other temperature combinations, CuS nanoparticles crystallize at 120 °C, which lowers resistance while increasing electron lifetime.
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This article discusses the progressive learning for structural tolerance online sequential extreme learning machine (PSTOS-ELM). PSTOS-ELM can save robust accuracy while updating the new data and the new class data on the online training situation. The robustness accuracy arises from using the householder block exact QR decomposition recursive least squares (HBQRD-RLS) of the PSTOS-ELM. This method is suitable for applications that have data streaming and often have new class data. Our experiment compares the PSTOS-ELM accuracy and accuracy robustness while data is updating with the batch-extreme learning machine (ELM) and structural tolerance online sequential extreme learning machine (STOS-ELM) that both must retrain the data in a new class data case. The experimental results show that PSTOS-ELM has accuracy and robustness comparable to ELM and STOS-ELM while also can update new class data immediately.
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This study aimed to develop a brain-computer interface that can control an electric wheelchair using electroencephalography (EEG) signals. First, we used the Mind Wave Mobile 2 device to capture raw EEG signals from the surface of the scalp. The signals were transformed into the frequency domain using fast Fourier transform (FFT) and filtered to monitor changes in attention and relaxation. Next, we performed time and frequency domain analyses to identify features for five eye gestures: opened, closed, blink per second, double blink, and lookup. The base state was the opened-eyes gesture, and we compared the features of the remaining four action gestures to the base state to identify potential gestures. We then built a multilayer neural network to classify these features into five signals that control the wheelchair’s movement. Finally, we designed an experimental wheelchair system to test the effectiveness of the proposed approach. The results demonstrate that the EEG classification was highly accurate and computationally efficient. Moreover, the average performance of the brain-controlled wheelchair system was over 75% across different individuals, which suggests the feasibility of this approach.
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
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Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Reconfigurable ultra wideband to narrowband antenna for cognitive radio applications using PIN diode
1. TELKOMNIKA Telecommunication, Computing, Electronics and Control
Vol. 18, No. 6, December 2020, pp. 2807∼2814
ISSN: 1693-6930, accredited First Grade by Kemenristekdikti, No: 21/E/KPT/2018
DOI: 10.12928/TELKOMNIKA.v18i6.16242 Ì 2807
Reconfigurable ultra wideband to narrowband antenna for
cognitive radio applications using PIN diode
Aziz El Fatimi1
, Seddik Bri2
, Adil Saadi3
1, 3
Control, Pilotage and Supervision of Systems (CPSS), National Graduate School of Arts and Crafts,
Moulay Ismail University, Morocco
2
Materials and instrumentation (MIM), High School of Technology, Moulay Ismail University, Morocco
Article Info
Article history:
Received Apr 3, 2020
Revised Jun 5, 2020
Accepted Jun 25, 2020
Keywords:
Narrowband
Patch antenna
PIN diode
Reconfigurable antenna
Wideband
ABSTRACT
Frequency reconfigurable antennas are very attractive for many wireless applications.
They offer many advantages such as simplicity and compactness. In this electronic
paper, we propose a reconfigurable antenna operating in the S and C bands. The
proposed antenna uses a BAP65-02 RF diode to switch between the ultra wideband
from 2.92 to 6.19 GHz to the narrowband from 2.92 to 3.93 GHz. The ultra wideband
is obtained by a partial rectangular ground plane with a symmetrical rectangular slot
and the narrowband is obtained by adding a parasitic element electrically connected
to the ground plane by the PIN diode when it is positively biased. This patch antenna
operates in the Federal Communications Commission band (FCC) and can be used for
biomedical applications such as radiometry imaging. The numerical simulation results
based on the finite element method and the finite integral method show a very good
agreement between them.
This is an open access article under the CC BY-SA license.
Corresponding Author:
Aziz El Fatimi,
Control, Pilotage and Supervision of Systems (CPSS),
National Graduate School of Arts and Crafts,
Moulay Ismail University,
B.P. 15290 EL Mansour Meknes 50500, Morocco.
Email: aziz.elfatimi@edu.umi.ac.ma
1. INTRODUCTION
The modern wireless communication technology is becoming increasingly important role in our daily
lives. In fact, antenna theory and experimental research results have evolved rapidly to give to a new technology
called reconfigurable antenna [1, 2]. The reconfigurable antenna concept means that its technical performance
can be modified in a flexible way according to the electrical, mechanical modifications or changing the material
properties that can be adjusted according to the actual situation. The reconfigurable antenna term was pro-
posed for the first time in 1960 to distinguish four main families, frequency reconfigurable antennas, antennas
reconfigurable in radiation, antennas reconfigurable in polarization and antennas with multiple reconfigurations
[3, 4]. By modifying the antenna structure, electrical length, substrate thickness, relative permittivity, geometry.
It is possible to reconfigure one or more parameters such as the frequency, the lobe diagram and the polarization
mode of the antenna. For these considerations, it has attracted several researchers to developer several designs
and optimization techniques for various applications [5–7].
With the rapid development of modern radar and communication systems, the number of antennas
Journal homepage: http://journal.uad.ac.id/index.php/TELKOMNIKA
2. 2808 Ì ISSN: 1693-6930
required is increasing for the purposes of communication, navigation, guidance, and alerting. This increases
weight, congestion, complexity and energy consumption which seriously affects the normal operation and
performance of the system. In order to solve these technical problems, it is recommended to use a single
antenna to perform the function of several antennas by continuously adjusting its structure [8–12].
The principle of reconfigurable frequency antennas is to change the current distribution by changing
the effective electrical length. Therefore, such an antenna can change continuously or discretely in a certain
band according to the technique used such as PIN diodes, switch MEMS, varactor, the modification of the
mechanical structure of the antenna and the modification of the dielectric properties of the substrate [13–18].
On the other hand, ultra wideband microstrip antennas, intended to monitor a band for detecting the free radio
spectrum, offer several advantages such as high data throughput and reduced power consumption, but have
a disadvantage of interfering with other bands particularly the WiMAX band from 3.3 to 3.9 GHz. For this
purpose, the frequency reconfigurable UWB antenna can be a better choice to overcome this problem [19–21].
In the following sections, will be seen successively, a detailed study on the evolution of the ground plane of the
proposed antenna, a comparison between the ideal switch and the real switch, the performances obtained and
finally the analysis of the specific absorption rate to check the level of security of our structure.
2. PIN DIODE MODEL
PIN diodes are widely used, from low frequency to high frequency applications, mainly used in the
RF domain. Because the RF resistance of the PIN diode is related to the DC bias current, it can be used as a
good RF switches or RF protection circuits. When the diode is positively biased, it is turned on short circuit
and when it is reverse biased, it is turned on open circuit. Typically, The resistance of the diode can vary
from 10 kΩ to less than 1 Ω by controlling its bias current. Though all the junction diodes show this type
of characteristic; structure and doping profile of PIN diodes are designed to achieve a wide range of variable
resistance and linearity with low bias current level [22].
The internal resistance of the PIN diode is the most fundamental electrical parameter that determines
the performance of the RF switch. Under the direct bias condition, the amount of charge stored in I-layer
corresponds to the direct bias current Id multiplied by the ambipolar lifetime τa. The total current is calculated
by the following equation with Qd is stored charge:[23]
Id(t) =
Qd
τa
+
dQd(t)
dt
(1)
The selected PIN diode is the BAP65-02, SOD523 (NXP Semiconductors), its technical features, extracted
from its datasheet [24], are as follows : continuous reverse voltage: 30 V, continuous forward current: 100 mA,
forward voltage: 1.1 V (max) at IF = 50 mA, reverse leakage current: 20 nA (max) at VR = 20 V, applications:
mobile communication transmit/receive switch, bandswitch for TV tuners. Figure 1 shows the two equivalent
models of the PIN diode (ON and OFF states).
PIN diode ON PIN diode OFF
Figure 1. Equivalent models of the PIN diode in both switching mode
3. ANTENNA DESIGN
The geometry of the proposed structure of the reconfigurable frequency antenna using the PIN diode is
illustrated in Figure 2. It is printed on a dielectric substrate FR4 of thickness 1.6 mm, with a permittivity of 4.4
and loss tangent of 0.02. The configuration of the antenna is composed of a simple monopole circular patch fed
by a feed line, connected to a 50 Ω SMA connector, placed on the opposite side of a partial ground plane where a
rectangular slot has been inserted. Frequency reconfigurability was achieved by a parasitic element electrically
TELKOMNIKA Telecommun Comput El Control, Vol. 18, No. 6, December 2020 : 2807 – 2814
3. TELKOMNIKA Telecommun Comput El Control Ì 2809
connected by a PIN diode with the modified ground plane. The switching of the PIN makes it possible to switch
from an ultra wideband to a narrowband. The optimized size of the compact antenna proposed is 31×38×1.6
mm3
. In order to justify the choice of the proposed structure, a series of parametric studies were investigated,
Figures 3 (a) , 3 (b) and 3 (c) show the evolution of the modification of the ground plane. The idea of adopting
the Defected Ground Structure made it possible to integrate a RF switch (PIN diode) without changing the
performance characteristics of the ultra wideband configuration.
Top view Bottom view
Figure 2. Top and bottom views of the proposed antenna
(a) (b) (c)
Figure 3. Different ground plane structures: (a) ordinary rectangular ground,
(b) rectangular ground with a rectangular slot, (c) proposed ground
Their frequency responses (return loss parameter vs frequency) are shown in Figure 4. As it observed
in this figure, the three ultra broadband structures have practically the same bandwidth. Therefore, it can be
concluded that the parasitic element has no effect on the performance of the UWB configuration but offers the
advantage of integrating a PIN diode to be able to switch from the ultra wideband to the narrowband (WiMAX
band).
Reconfigurable ultra wideband to narrowband antenna for cognitive radio applications... (Aziz El Fatimi)
4. 2810 Ì ISSN: 1693-6930
Figure 4. Reflection coefficient vs frequency of all the ground plane structures
4. RESULTS AND DISCUSSION
4.1. Proposed antenna analysis
The proposed antenna operates in two modes, narrowband mode for the WiMAX band when the
switch is in the ON state and ultra wideband mode intended for cognitive applications in S and C bands when
the switch is in the off state. A study on the bandwidth limitation behavior was performed using two ideal and
real switches. The numerical simulation results are shown in Figures 5 and 6.
Figure 5. Frequency response of the reconfigurable
antenna with ideal switch calculated by FEM and
FIT solvers
Figure 6. Frequency response of the reconfigurable
antenna with real switch calculated by FEM and
FIT solvers
As can be seen from the graphs, the actual RF switch reduces the band in wideband mode. This
limitation is mainly due to the parasitic effect of the passive components: inductance, capictity and resistance.
On the other hand, there is a good agreement between the values calculated by the finite element method
and the finite integral method. However, there are small shifting between solvers that may be due to reasons
such as the approximations and the three-dimensional mesh adopted by each method. The status report of
the ideal and real switches at ON and OFF states using the two solvers FEM and FIT is described in Table
1. The transition between ultra wideband and narrowband behavior can be explained by the change in surface
current distribution. Indeed, the state of the RF switch, activated or deactivated really defines the electrical
length of the antenna structure. The state of the ON switch forces the antenna to operate in narrowband mode
TELKOMNIKA Telecommun Comput El Control, Vol. 18, No. 6, December 2020 : 2807 – 2814
5. TELKOMNIKA Telecommun Comput El Control Ì 2811
while the OFF state forces the antenna to operate in ultra wideband mode. Figure 7 shows the surface current
distribution calculated using the finite element method at the 3.34 GHz resonance frequency. The current is
weakly distributed in the blue regions while the distribution intensifies in the red regions. It is evident that the
RF switch in activated state (ON state) considerably modifies the electrical length of the structure.
Table 1. Status report of the ideal and real switches at ON and OFF states using the two solvers FEM and FIT
States Solver Switch No. of band Frequency [GHz] Wideband [GHZ]
FEM Ideal 2 2.94 - 4.08 4.87 - 5.96 1.14 1.10
3-8 State Real 1 2.92 - 3.93 1.01
2-8 ON FIT Ideal 2 2.68 - 3.74 4.89 - 6.01 1.05 1.11
3-8 Real 1 2.67 -3.62 0.94
FEM Ideal 1 2.89 -10.3 7.14
3-8 State Real 1 2.92 - 6.19 3.27
2-8 OFF FIT Ideal 1 2.66 -10.19 7.52
3-8 Real 1 2.66 -6.13 3.47
RF switch OFF RF switch ON
Figure 7. Calculated current distribution of the proposed antenna at 3.34 GHz
4.2. Proposed antenna performance
Finally, The proposed design values of the reconfigurable frequency antenna are optimized by a solver
based on the finite element method (FEM) and validated by the finite integral method (FIT). The final geometry
of the proposed antenna is shown in Figure 8 and the optimized dimensions are listed in Table 2.
Zoom out Zoom in
Figure 8. Final geometry of the proposed reconfigurable antenna
The radiation patterns in the E-palne (φ = 90◦
- XY plane) and H-plane (φ = 0◦
- XZ plane) are calcu-
lated at 3.34 GHz at ON state and at 3.39 GHz and 5.59 GHz at the OFF state, as shown in Figures 9, 10, and
Reconfigurable ultra wideband to narrowband antenna for cognitive radio applications... (Aziz El Fatimi)
6. 2812 Ì ISSN: 1693-6930
11. It is observed that the E is in symmetry while the H is omnidirectional. The rectangular representation of
the simulated peack gain in the activated and deactivated state of the PIN diode switch of the antenna designed
is shown in Figure 12. In both modes, the gain achieved is very good, greater than 4.96 dB when the switch is
ON and greater than 3.65 when the switch is OFF. It can be observed that the PIN diode significantly influences
the gain when it is activated.
Table 2. Optimized dimensions of the proposed reconfigurable antenna
Parameter Ws Ls Lg R Wf Lf W1 L1 W2 L2 W3 L3
Value [mm] 31 38 11.9 12 2.5 12 4 2 1 2 2 1
Figure 9. Radiation pattern at 3.28 GHz, RF switch ON; φ = 0◦
, φ = 90◦
Figure 10. Radiations pattern at 3.39 GHz, RF
switch OFF; φ = 0◦
, φ = 90◦
Figure 11. Radiations pattern at 5.59 GHz, RF
switch OFF; φ = 0◦
, φ = 90◦
4.3. Specific absorption rate evaluation
The proposed structure covers the band [2.92 - 6.19] GHz in ultra wideband mode and the band [2.92
- 3.93] GHz in narrowband mode, both modes are included in the FCC (Federal Communications Commission)
[3.1 - 10.6] GHz band to be used safety for communication systems [25, 26]. However, the study of the level of
the specific absorption rate on the human body should be done carefully. According to the IEEE C95.3, 2002
safety recommendations [27], the average SAR for 1 g of human tissue must be less than 1.6 W/kg. The study
conducted in this paper was performed at a distance of 10 mm on body phantom of 50×57×21 mm3
composed
TELKOMNIKA Telecommun Comput El Control, Vol. 18, No. 6, December 2020 : 2807 – 2814
7. TELKOMNIKA Telecommun Comput El Control Ì 2813
of bone, muscle and skin tissues, their physical properties are respectively r
bone = 12.03, σbone = 0.2156 S/m,
r
muscle = 54.066, σmuscle = 1.1553 S/m, r
skin = 39.59, σskin = 1.0465 S/m [28]. As shown in Figure 13,
the designed antenna can operate safely up to an input power of 29 mW at 3.34 GHz where the max SAR is
1.562 W/Kg.
Figure 12. Peak gain vs frequency of
both RF switch states
Figure 13. Calculated distribution SAR on body
phantom at 3.34 GHz in both ON and OFF states
5. CONCLUSION
In summary, a compact frequency reconfigurable circular antenna has been designed, studied and
analyzed in this paper. This structure, intended for wireless cognitive applications in the S and C bands, works
in the narrowband mode from 2.92 to 3.93 GHz when the RF switch is activated and in the ultra wideband
mode from 2.92 to 6.19 GHz when the switch is deactivated. The antenna is designed on a dielectric substrate
FR4 of thickness 1.6 mm, with a permittivity of 4.4 and loss tangent of 0.02 uses the diode switch BAP65-
02,SOD523 to change the effective electrical length of the antenna to obtain frequency reconfigurability. The
results calculated using the finite element method and the finite integrals method are very coherent, which
allows this antenna to be a candidate choice for wireless cognitive applications.
REFERENCES
[1] D. Tse, P. Viswanath, “ Fundamentals of wireless communication,” Cambridge University Press, 2005.
[2] S. Simon, A. Arag´on-Zavala, “Antennas and propagation for wireless communication systems”, Wiley,
2007.
[3] N. Pavel, R. Martinez, S. J. Kelly., “Systems and methods for a reconfigurable antenna,” U.S. Patent
Application, no. 15, pp. 632-830, 2017.
[4] M. L. Van Blaricum, “A brief history of photonic antenna reconfiguration,” International Topical Meeting
on Microwave Photonics MWP 2000 (Cat. No. 00EX430), pp. 9-12, 2000.
[5] C. J. Panagamuwa, C. Chauraya, J. C. Vardaxoglou, “Frequency and beam reconfigurable antenna using
photoconducting switches,” IEEE Transactions on Antennas and Propagation, vol. 54, no. 2, pp. 449-454,
2006. DOI: 10.1109/TAP.2005.863393
[6] V. Bharambe, et al., “Reversibly Reconfigurable Liquid Metal Patch Antenna Using A Superhydrophobic
Spray-Coating,” IEEE International Symposium on Antennas and Propagation & USNC/URSI National
Radio Science Meeting, pp. 287-288, 2018. DOI: 10.1109/APUSNCURSINRSM.2018.8608814
[7] G. Kiesel, E. Strates, C. Phillips, “Beam forming with a reconfigurable antenna array,” IEEE International
Symposium on Phased Array Systems and Technology (PAST), pp. 1-3, 2016. DOI: 10.1109/AR-
RAY.2016.7832641
[8] A. El fatimi, S. Bri, and A. Saadi, “UWB antenna with circular patch for early breast cancer detection,”
TELKOMNIKA Telecommunication Computing Electronics and Control, Vol. 17, no. 5, pp. 2370-2377,
October 2019. DOI: 10.12928/TELKOMNIKA.v17i5.12757
Reconfigurable ultra wideband to narrowband antenna for cognitive radio applications... (Aziz El Fatimi)
8. 2814 Ì ISSN: 1693-6930
[9] D. K. Barton, “Modern radar system analysis”, Norwood, MA, Artech House, 1988.
[10] T. E. Tuncer, B. Friedlander, “Classical and modern direction-of-arrival estimation”, Academic Press,
2009.
[11] B. R. Mahafza, “Introduction to radar analysis”, Chapman and Hall/CRC, 2017.
[12] L. Ge, et al., “Reconfigurable Magneto-Electric Dipole Antennas for Base Stations in Modern Wireless
Communication Systems,” Wireless Communications and Mobile Computing, vol. 2018, no. 1, pp. 1-8,
May 2018. DOI: https://doi.org/10.1155/2018/2408923
[13] A. Elkorany, S. Saad, D. Saleeb, “Compact Reconfigurable Band Notched UWB Cylindrical Dielectric
Resonator Antenna Using Single Varactor Diode,” Advanced Electromagnetics, vol. 7, no. 3, pp. 35-39,
2018. DOI: https://doi.org/10.7716/aem.v7i3.672
[14] M. Ng Mou Kehn, O. Quevedo-Teruel, E. Rajo-Iglesias, “Reconfigurable loaded planar inverted-f antenna
using varactor diodes,” IEEE Antennas and Wireless Propagation Letters, vol. 10, pp. 466–468, 2011.
DOI: 10.1109/LAWP.2011.2153174
[15] Y. Xu, Y. Tian, et al., “A novel RF MEMS switch on frequency reconfigurable antenna
application,” Microsystem Technologies, vol. 24, no. September, pp. 3833-3841, 2018. DOI:
https://doi.org/10.1007/s00542-018-3863-9.
[16] Y. Tawk, J. Costantine, C. G. Christodoulou, “A rotatable reconfigurable antenna for cognitive radio
applications,” IEEE Radio and Wireless Symposium, pp. 158-161, 2011.
[17] G. Ruvio, M. J. Ammann, Z. N. Chen, “Wideband reconfigurable rolled planar monopole an-
tenna,” IEEE Transactions on Antennas and Propagation, vol. 55, no. 6, pp. 1760-1767, 2007. DOI:
10.1109/TAP.2007.898575
[18] M. Saravanan, M. J. S. Rangachar, “Polarization Reconfigurable Square Patch Antenna for Wire-
less Communications,” Advanced Electromagnetics, vol. 7, no. 4, pp. 103–108, 2018. DOI:
https://doi.org/10.7716/aem.v7i4.805
[19] R. Kumar, S. A. Kumar, and K. P. Bhuvana, “Preparation and evaluation of bioactivity of porous bio-
glass tablets for bone tissue regeneration,” SciMedicine Journal, vol. 1, no. 3, pp. 112–123, 2019. DOI:
10.28991/SciMedJ-2019-0103-1
[20] H. H. Ahmed and S. R. Al-Zaidee, “Experimental investigation for effects of mini-piles on the struc-
tural response of raft foundations,” Civil Engineering Journal, vol. 5, no. 5, pp. 1084–1098, 2019. DOI:
10.28991/cej-2019-03091313
[21] O. A. Yamini, S. H. Mousavi, and M. Kavianpour, “Experimental investigation of using geo-
textile filter layer in articulated concrete block mattress revetment on coastal embankment,”
Journal of Ocean Engineering and Marine Energy, vol. 5, no. 2, pp. 119–133, 2019. DOI:
https://doi.org/10.1061/9780872626874.060
[22] S. Abbasiniazare, O. Manoochehri, K. Forooraghi, “A Reconfigurable Printed Dipole Antenna Using RF
PIN Diodes,” Microwave and Optical Technology Letters, vol. 56, no. 5, pp. 1151-1155, 2014. DOI:
https://doi.org/10.1002/mop.28293
[23] S. C. Bera, “P-I-N Diode. In: Microwave Active Devices and Circuits for Communication,” Lecture Notes
in Electrical Engineering, vol 533. Springer, 2019.
[24] NXP, “BAP65-02 Silicon PIN diode, Rev. 6.1 — 28 January 2019 Product data sheet”, 2019. [Online],
Available: https://www.nxp.com/docs/en/data-sheet/BAP65-02.pdf.
[25] R. H. Coase, “The federal communications commission,” Private and Common Property, Routledge, pp.
53-92, 2013.
[26] K. Javadi and N. Komjani, “Investigation into low sar pifa antenna and design a very low sar u-slot antenna
using frequency selective surface for cell-phones and wearable applications,” Emerging Science Journal,
vol. 1, no. 3, pp. 145–157, 2017. DOI: 10.28991/ijse-01117
[27] “Recommended Practice for Measurements and Computations of Radio Frequency Electromagnetic
Fields With Respect to Human Exposure to Such Fields, 100 kHz-300 GHz,” IEEE Standard C95.3,
pp. 1-126, 2002.
[28] J. Kumar, B. Basu, F. A. Talukdar, “Modeling of a PIN Diode RF Switch for Re configurable Antenna
Application,” Scientia Iranica, 2018. DOI: 10.24200/SCI.2018.20110
TELKOMNIKA Telecommun Comput El Control, Vol. 18, No. 6, December 2020 : 2807 – 2814