In this paper a fifth order wide-band Chebyshev micro-strip filter is designed at 5.2 GHz frequency, where the spectrum contains white spaces. The fifth order is extended to 7th, 9th, 11th, and 13th order and simulated using HFSS EM simulator. Simulation results show that compared to 5th order, the higher order filters provide more and more reduction in out-of-band emissions in increasing order from 5th to 13th order filter. A 13th order filter is fabricated and tested for more reduction in the OOBE by using dumbbell shaped slots as defected ground plane structure. Five such slots are made in the ground plane for better results to reduce more OOBE. This 13th order filer with slots is fabricated and tested. The substrate chosen is FR4 with height 1.6 mm. Here we have given a mathematical treatment for emission mask for OOBE according to ITU recommendations. The designed filter’s transmission characteristics from port 1 to port 2 give good agreement with the recommendations.
{"title":"Analysis of higher order Microstrip Filter to Reduce Out-of-Band Emissions","authors":"M. K H, S. Mehta","doi":"10.7716/aem.v12i1.1693","DOIUrl":"https://doi.org/10.7716/aem.v12i1.1693","url":null,"abstract":"In this paper a fifth order wide-band Chebyshev micro-strip filter is designed at 5.2 GHz frequency, where the spectrum contains white spaces. The fifth order is extended to 7th, 9th, 11th, and 13th order and simulated using HFSS EM simulator. Simulation results show that compared to 5th order, the higher order filters provide more and more reduction in out-of-band emissions in increasing order from 5th to 13th order filter. A 13th order filter is fabricated and tested for more reduction in the OOBE by using dumbbell shaped slots as defected ground plane structure. Five such slots are made in the ground plane for better results to reduce more OOBE. This 13th order filer with slots is fabricated and tested. The substrate chosen is FR4 with height 1.6 mm. Here we have given a mathematical treatment for emission mask for OOBE according to ITU recommendations. The designed filter’s transmission characteristics from port 1 to port 2 give good agreement with the recommendations.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44568170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The present work studied effects of transformation of refractive index periodicity on electromagnetic wave propagation through grating waveguides. In lieu of the standard refractive index periodicity, although its unit cell consists of two kinds of materials, we consider few such unit cells as a new supercell, where the material parameters in a standard unit cell are changed. It has been shown how by changing parameters of the periodicity to control the wavelength and intensity of resonant optical mode (guided mode resonance) arising inside grating area. High quality factor calculated for the specific angle of incidence and periodicity parameter. Thus, we demonstrated that transformation of refractive index provides additional tools of controlling the GMR, and that means the sample can be designed more functional in terms of real application.
{"title":"Electromagnetic guided mode resonance in dielectric grating affected by transformation of refractive index periodicity","authors":"A. Abramov, Y. Yue, V. Rumyantsev","doi":"10.7716/aem.v12i1.2127","DOIUrl":"https://doi.org/10.7716/aem.v12i1.2127","url":null,"abstract":"The present work studied effects of transformation of refractive index periodicity on electromagnetic wave propagation through grating waveguides. In lieu of the standard refractive index periodicity, although its unit cell consists of two kinds of materials, we consider few such unit cells as a new supercell, where the material parameters in a standard unit cell are changed. It has been shown how by changing parameters of the periodicity to control the wavelength and intensity of resonant optical mode (guided mode resonance) arising inside grating area. High quality factor calculated for the specific angle of incidence and periodicity parameter. Thus, we demonstrated that transformation of refractive index provides additional tools of controlling the GMR, and that means the sample can be designed more functional in terms of real application.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43166910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Numerical results for the attenuation constant obtained by using the generalized telegraphist’s equations (GTEs) based electromagnetic analysis method and comparison with the HFSS (High Frequency Structure Simulator) results are reported. To calculate the attenuation constant with the GTEs method, not only the amplitudes of the voltage modes but also the amplitudes of the current modes must be found. In this paper, it is demonstrated that the relationships reported by other authors for the amplitudes of the current modes are not correct and new ones are proposed. To validate these relationships, the attenuation constants for homogeneous and different partially dielectric-filled rectangular waveguides are computed for the fundamental propagation mode by using the GTEs based analysis method and the results are compared with those obtained with HFSS. It is shown that using the revised relationships for the amplitudes of the current modes, the GTE method can be used to compute accurately the propagation and attenuation constant, but only for propagation modes in which the components of the electric field are not oriented perpendicular to the interface between different dielectrics. This limitation is not due to the proposed current mode relationships, but is due to the GTE method which cannot highlight the electric field discontinuities.
{"title":"On the Computation of the Attenuation Constant by Using the Generalized Telegraphist’s Equations Based Electromagnetic Analysis Method","authors":"S. Simion","doi":"10.7716/aem.v12i1.2086","DOIUrl":"https://doi.org/10.7716/aem.v12i1.2086","url":null,"abstract":"Numerical results for the attenuation constant obtained by using the generalized telegraphist’s equations (GTEs) based electromagnetic analysis method and comparison with the HFSS (High Frequency Structure Simulator) results are reported. To calculate the attenuation constant with the GTEs method, not only the amplitudes of the voltage modes but also the amplitudes of the current modes must be found. In this paper, it is demonstrated that the relationships reported by other authors for the amplitudes of the current modes are not correct and new ones are proposed. To validate these relationships, the attenuation constants for homogeneous and different partially dielectric-filled rectangular waveguides are computed for the fundamental propagation mode by using the GTEs based analysis method and the results are compared with those obtained with HFSS. It is shown that using the revised relationships for the amplitudes of the current modes, the GTE method can be used to compute accurately the propagation and attenuation constant, but only for propagation modes in which the components of the electric field are not oriented perpendicular to the interface between different dielectrics. This limitation is not due to the proposed current mode relationships, but is due to the GTE method which cannot highlight the electric field discontinuities.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47653921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A low-profile printed slot antenna (PSA) backed by broadband planar artificial magnetic conductor (AMC) is introduced in this study. Firstly, a suggested PSA with the radiating tapered slots excited by coplanar-waveguide (CPW) is used to expand the bandwidth in the measured range of 9-11 GHz (S11≤ -10 dB). Then, the suggested planar AMC surface as the ground plane of the antenna is inserted into the PSA to gain improved radiation efficiency. The realized result from the PSA with the 9×9 planar AMC array exhibits -10 dB measured impedance bandwidth from 6.63 to 13.73 GHz (70%). The suggested PSA with AMC compared to the PSA without AMC exhibits a size reduction of 60%, enhanced bandwidth of 50%, and excellent impedance matching with a minimum value of almost -40 dB. The novel AMC unit cell is realized to operate at 10.14 GHz with an AMC bandwidth of 8-12.35 GHz (43.1%) for X-band operation. Besides, by loading a periodic AMC unit cells into PSA, a high gain of more than 11 dBi with uni-directional radiation patterns is achieved.
{"title":"Broadband Printed Tapered Slot Antenna Fed by CPW Fulfilled with Planar Artificial Magnetic Conductor for X-Band Operation","authors":"H. Malekpoor","doi":"10.7716/aem.v12i1.2087","DOIUrl":"https://doi.org/10.7716/aem.v12i1.2087","url":null,"abstract":"A low-profile printed slot antenna (PSA) backed by broadband planar artificial magnetic conductor (AMC) is introduced in this study. Firstly, a suggested PSA with the radiating tapered slots excited by coplanar-waveguide (CPW) is used to expand the bandwidth in the measured range of 9-11 GHz (S11≤ -10 dB). Then, the suggested planar AMC surface as the ground plane of the antenna is inserted into the PSA to gain improved radiation efficiency. The realized result from the PSA with the 9×9 planar AMC array exhibits -10 dB measured impedance bandwidth from 6.63 to 13.73 GHz (70%). The suggested PSA with AMC compared to the PSA without AMC exhibits a size reduction of 60%, enhanced bandwidth of 50%, and excellent impedance matching with a minimum value of almost -40 dB. The novel AMC unit cell is realized to operate at 10.14 GHz with an AMC bandwidth of 8-12.35 GHz (43.1%) for X-band operation. Besides, by loading a periodic AMC unit cells into PSA, a high gain of more than 11 dBi with uni-directional radiation patterns is achieved.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41788000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
According to the analysis of shear flow and pressure difference flow of MR fluids, the damping force of MR shear-valve damping force was analysed and calculated, and a magnetic circuit of Magnetorheological (MR) damper was designed. Based on the designed magnetic circuit, the degree of magnetic saturation and the dynamic characteristics of MR fluid damper, such as impedance, current, velocity and frequency were investigated. Magnetic induction testing of damping clearance was conducted, the test results show that when the coil current is 1.4A, the magnetic induction intensity reaches 0.55T.The bench test results show that when the piston speed is constant and the current is less than 1.36A, the variation range of damping force increases significantly. However, when the current is greater than 1.36A, the damping force tends to be stable and the coil reaches magnetic saturation, and energy indication characteristic of MR damper also show the same trend, which are consistent with the theoretical results. The results of this study can provide useful guidance for the magnetic circuit design of shear-valve MR fluid damper.
{"title":"Theoretical design and experimental study of magnetic circuit for magnetorheological (MR) damper of shear-valve mode","authors":"Y. Liu, A. Li, Z. Sun, S. Chen","doi":"10.7716/aem.v11i4.2055","DOIUrl":"https://doi.org/10.7716/aem.v11i4.2055","url":null,"abstract":"According to the analysis of shear flow and pressure difference flow of MR fluids, the damping force of MR shear-valve damping force was analysed and calculated, and a magnetic circuit of Magnetorheological (MR) damper was designed. Based on the designed magnetic circuit, the degree of magnetic saturation and the dynamic characteristics of MR fluid damper, such as impedance, current, velocity and frequency were investigated. Magnetic induction testing of damping clearance was conducted, the test results show that when the coil current is 1.4A, the magnetic induction intensity reaches 0.55T.The bench test results show that when the piston speed is constant and the current is less than 1.36A, the variation range of damping force increases significantly. However, when the current is greater than 1.36A, the damping force tends to be stable and the coil reaches magnetic saturation, and energy indication characteristic of MR damper also show the same trend, which are consistent with the theoretical results. The results of this study can provide useful guidance for the magnetic circuit design of shear-valve MR fluid damper.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46229311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents a triple-band low-profile circularly polarized (CP) hexagonal dielectric resonator antenna (HDRA) array for various wireless applications. A 4-element linear array is designed using a simple microstrip power divider to improve the performance of the HDRA. This HDRA excites TEd01 mode at a first resonant frequency of 1.52 GHz. The proposed design operates in three frequency bands, i.e. 1.44 - 1.61 GHz, 2.95 - 3.27 GHz, and 4.00 - 4.84 GHz with the fractional bandwidth of 10.98%,11.02% and 22.20%, respectively. It also provides good gain and more than 70% of radiation efficiency with a better radiation pattern at all the resonating points. Further, it has a CP bandwidth of 50 MHz and 650 MHz around 3.12 GHz and 4.25 GHz, respectively. The proposed HDRA array is suitable for different wireless applications such as GPS (1 - 2 GHz), WiMAX (2 - 4 GHz), and WLAN (4 - 8 GHz).
{"title":"A Low-profile 4-element Circularly Polarized Hexagonal DRA Array for Triple-band Wireless Applications","authors":"A. Vahora, K. Pandya","doi":"10.7716/aem.v11i4.2004","DOIUrl":"https://doi.org/10.7716/aem.v11i4.2004","url":null,"abstract":"This paper presents a triple-band low-profile circularly polarized (CP) hexagonal dielectric resonator antenna (HDRA) array for various wireless applications. A 4-element linear array is designed using a simple microstrip power divider to improve the performance of the HDRA. This HDRA excites TEd01 mode at a first resonant frequency of 1.52 GHz. The proposed design operates in three frequency bands, i.e. 1.44 - 1.61 GHz, 2.95 - 3.27 GHz, and 4.00 - 4.84 GHz with the fractional bandwidth of 10.98%,11.02% and 22.20%, respectively. It also provides good gain and more than 70% of radiation efficiency with a better radiation pattern at all the resonating points. Further, it has a CP bandwidth of 50 MHz and 650 MHz around 3.12 GHz and 4.25 GHz, respectively. The proposed HDRA array is suitable for different wireless applications such as GPS (1 - 2 GHz), WiMAX (2 - 4 GHz), and WLAN (4 - 8 GHz).","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41615419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper develops new integral formulas intended for detailed studies of electromagnetics normal modes in spherical and spherical annular cavities.
本文提出了新的积分公式，用于详细研究球形和球形环形腔中的电磁学法模。
{"title":"Some integrals involving squares of Bessel functions or of generalized Legendre polynomials","authors":"E. Matagne","doi":"10.7716/aem.v11i4.1946","DOIUrl":"https://doi.org/10.7716/aem.v11i4.1946","url":null,"abstract":"This paper develops new integral formulas intended for detailed studies of electromagnetics normal modes in spherical and spherical annular cavities.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46506120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper develops analytical expressions of energy, thrust and losses for all electromagnetics normal modes in spherical and annular spherical cavities. The implications on the spherical Casimir effect are also investigated.
{"title":"Detailed Analysis of the Electromagnetic Normal Modes of Spherical and Annular Spherical Cavities: Energy, Thrust and Losses. Implications on the Spherical Casimir Effect","authors":"E. Matagne","doi":"10.7716/aem.v11i4.1945","DOIUrl":"https://doi.org/10.7716/aem.v11i4.1945","url":null,"abstract":"This paper develops analytical expressions of energy, thrust and losses for all electromagnetics normal modes in spherical and annular spherical cavities. The implications on the spherical Casimir effect are also investigated.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48146634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
For the efficient utilization of electromagnetic radio spectrum cognitive radio communication system is employed, which deals with the spectrum scarcity. An efficient antenna is essential for the appropriate selection of the available frequencies. This paper presents the design and implementation of frequency reconfigurable antenna for cognitive radio applications. Reconfigurable inverted U-shape microstrip patch antenna feeding by 50 W microstrip line is designed and implemented. The designed and implemented antenna applied for switching frequency between 3.25 GHz to 4.1 GHz by choosing a specific sub-band from the specified wideband. The frequency reconfiguration was achieved by using twelve PIN diode switches by placing them on the slotted ground plane of the antenna. The PIN diodes were organized in such a way as to alter antenna bandwidth and to shift the operating band. The switching of PIN diodes controlled using the microcontroller to select the appropriate frequency. The performance of the simulated and fabricated antenna is investigated using different parameters.
{"title":"Frequency selective reconfigurable microstrip antenna for cognitive radio applications","authors":"D. S. Aldar","doi":"10.7716/aem.v11i4.1696","DOIUrl":"https://doi.org/10.7716/aem.v11i4.1696","url":null,"abstract":"For the efficient utilization of electromagnetic radio spectrum cognitive radio communication system is employed, which deals with the spectrum scarcity. An efficient antenna is essential for the appropriate selection of the available frequencies. This paper presents the design and implementation of frequency reconfigurable antenna for cognitive radio applications. Reconfigurable inverted U-shape microstrip patch antenna feeding by 50 W microstrip line is designed and implemented. The designed and implemented antenna applied for switching frequency between 3.25 GHz to 4.1 GHz by choosing a specific sub-band from the specified wideband. The frequency reconfiguration was achieved by using twelve PIN diode switches by placing them on the slotted ground plane of the antenna. The PIN diodes were organized in such a way as to alter antenna bandwidth and to shift the operating band. The switching of PIN diodes controlled using the microcontroller to select the appropriate frequency. The performance of the simulated and fabricated antenna is investigated using different parameters.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44642751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Industrial Internet of Things (IIoT) is a domain between IoT and Industry 4.0 that brings an evolution in automation and data exchange. Multiband and the wideband antenna are an important part to support high-rate IoT/IIoT communication through the wireless systems. In this study, we optimized a Vivaldi antenna for triple-band operation at well-known IIoT bands without adding any slot or extra structure. The antenna gets a large bandwidth of over 8%, 12%, and 19% at 2.4GHz, 4GHz, and 5.6GHz resonant frequencies, respectively. To improve several antenna characteristics such as resistance matching, gain, and radiation efficiency, an L shape symmetric Substrate Integrated Waveguide (SIW) structure is proposed. At the 5.6 GHz band, the SIW antenna achieves over 25% increase in radiation efficiency that reaches 99% although FR4 substrate is chosen to design the antenna. The proposed Vivaldi antenna is analyzed using CST simulation and measured using VNA equipment with an agree well result. Besides, we also set up a reality wireless system to test the antenna at two important IIoT bands: 2.4GHz and 5GHz.
{"title":"The Performance Enhancement of Triple-band Vivaldi Antenna using SIW Structure for IIoT applications","authors":"T. Nguyen, T. Duong, D. Pham","doi":"10.7716/aem.v11i4.2010","DOIUrl":"https://doi.org/10.7716/aem.v11i4.2010","url":null,"abstract":"The Industrial Internet of Things (IIoT) is a domain between IoT and Industry 4.0 that brings an evolution in automation and data exchange. Multiband and the wideband antenna are an important part to support high-rate IoT/IIoT communication through the wireless systems. In this study, we optimized a Vivaldi antenna for triple-band operation at well-known IIoT bands without adding any slot or extra structure. The antenna gets a large bandwidth of over 8%, 12%, and 19% at 2.4GHz, 4GHz, and 5.6GHz resonant frequencies, respectively. To improve several antenna characteristics such as resistance matching, gain, and radiation efficiency, an L shape symmetric Substrate Integrated Waveguide (SIW) structure is proposed. At the 5.6 GHz band, the SIW antenna achieves over 25% increase in radiation efficiency that reaches 99% although FR4 substrate is chosen to design the antenna. The proposed Vivaldi antenna is analyzed using CST simulation and measured using VNA equipment with an agree well result. Besides, we also set up a reality wireless system to test the antenna at two important IIoT bands: 2.4GHz and 5GHz.","PeriodicalId":44653,"journal":{"name":"Advanced Electromagnetics","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42496976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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