Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714564
Serhat Erdogan, Madhavan Swaminathan
This paper presents design, fabrication and measurement results of a printed quasi-Yagi antenna with monopole radiator on glass substrate with low-loss polymer buildup films operating in D-band. Simulated peak gain of the antenna is 6.2 dBi, measured impedance bandwidth $left(left|S_{11}right|lt-10 mathrm{~dB}right)$ covers the entire D-band $(110-170 mathrm{GHz})$. Size of the antenna is $0.887 mathrm{~mm}$ $times 0.919 mathrm{~mm}$, or $0.413 lambda_{0} times 0.429 lambda_{0}$ at 140 GHz. Return loss measurements show high repeatability. Wide bandwidth of the antenna, high simulated gain, compact size, and advantages of glass-based packages in terms of supporting high level of integration using Glass Panel Embedding makes it suitable for handset devices for sub-THz wireless communications in D-band.
{"title":"D-band Quasi-Yagi Antenna in Glass-based Package","authors":"Serhat Erdogan, Madhavan Swaminathan","doi":"10.1109/imarc49196.2021.9714564","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714564","url":null,"abstract":"This paper presents design, fabrication and measurement results of a printed quasi-Yagi antenna with monopole radiator on glass substrate with low-loss polymer buildup films operating in D-band. Simulated peak gain of the antenna is 6.2 dBi, measured impedance bandwidth $left(left|S_{11}right|lt-10 mathrm{~dB}right)$ covers the entire D-band $(110-170 mathrm{GHz})$. Size of the antenna is $0.887 mathrm{~mm}$ $times 0.919 mathrm{~mm}$, or $0.413 lambda_{0} times 0.429 lambda_{0}$ at 140 GHz. Return loss measurements show high repeatability. Wide bandwidth of the antenna, high simulated gain, compact size, and advantages of glass-based packages in terms of supporting high level of integration using Glass Panel Embedding makes it suitable for handset devices for sub-THz wireless communications in D-band.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115890700","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714606
M. Kahar, M. Mandal, G. Chattopadhyay
This paper presents a comparative study on the insertion losses for E- and H-plane waveguide-based bandpass filters at THz frequencies. It is shown that the H-plane filters suffer from high loss due to higher surface current on the coupling irises. Finally, two E-plane filters and two H-plane filters with the fractional bandwidths of 2% and 2.5% are designed at 510 and 552.7 GHz, respectively. The filter responses are verified by using two commercially available electromagnetic full-wave simulators. A sensitivity analysis is also presented to estimate the changes in filter responses due to fabrication tolerances.
{"title":"Loss Studies For Waveguide Based E- and H-plane Bandpass Filters at Terahertz Frequencies","authors":"M. Kahar, M. Mandal, G. Chattopadhyay","doi":"10.1109/imarc49196.2021.9714606","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714606","url":null,"abstract":"This paper presents a comparative study on the insertion losses for E- and H-plane waveguide-based bandpass filters at THz frequencies. It is shown that the H-plane filters suffer from high loss due to higher surface current on the coupling irises. Finally, two E-plane filters and two H-plane filters with the fractional bandwidths of 2% and 2.5% are designed at 510 and 552.7 GHz, respectively. The filter responses are verified by using two commercially available electromagnetic full-wave simulators. A sensitivity analysis is also presented to estimate the changes in filter responses due to fabrication tolerances.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120921632","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714571
Shubhadip Paul, A. Banerjee, V. S. Bhadouria, M. Akhtar
In this paper, a Zero index metasurface (ZIM) loaded highly directive Yagi antenna is proposed for Microwave imaging of corrosion in steel-reinforced concrete (RC) structure. The zero index metasurface (ZIM) enhanced the gain of the reference Yagi antenna by $4mathrm{~dB}$ at 9GHz. A numerical model of the cylindrical metallic targets with and without corrosion inside the RC structure is designed for electromagnetic (EM) analysis. The proposed ZIM-based Yagi antenna transmits $mathbf{E M}$ signal and receives the scattered data from the RC structure, which is applied into a piecewise synthetic aperture radar (SAR) algorithm to enhance the spatial resolution of the target object. The numerical results show that the proposed microwave imaging technique using the ZIMbased Yagi antenna and SAR algorithm detects both the cylindrical shape metallic target with and without corrosion inside the RC structure and is also able to identify the corroded metallic target.
{"title":"Investigation of Corrosion in Steel Reinforced Concrete Structure using Directive ZIM based Yagi Antenna and SAR Technique","authors":"Shubhadip Paul, A. Banerjee, V. S. Bhadouria, M. Akhtar","doi":"10.1109/imarc49196.2021.9714571","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714571","url":null,"abstract":"In this paper, a Zero index metasurface (ZIM) loaded highly directive Yagi antenna is proposed for Microwave imaging of corrosion in steel-reinforced concrete (RC) structure. The zero index metasurface (ZIM) enhanced the gain of the reference Yagi antenna by $4mathrm{~dB}$ at 9GHz. A numerical model of the cylindrical metallic targets with and without corrosion inside the RC structure is designed for electromagnetic (EM) analysis. The proposed ZIM-based Yagi antenna transmits $mathbf{E M}$ signal and receives the scattered data from the RC structure, which is applied into a piecewise synthetic aperture radar (SAR) algorithm to enhance the spatial resolution of the target object. The numerical results show that the proposed microwave imaging technique using the ZIMbased Yagi antenna and SAR algorithm detects both the cylindrical shape metallic target with and without corrosion inside the RC structure and is also able to identify the corroded metallic target.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130149411","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714651
Nishant Shukla, Vikas Gupta, P. Ambati
A Q-band 4-pole quasi elliptic E-plane waveguide filter is designed and simulated. Filter circuit is based on liquid crystal polymer substrate so that the better fabrication tolerances can be achieved through lithography at Q-band frequency along with thermal control that liquid crystal polymers can provide due to the availability of broad range of material thermal coefficient of expansion (TCE). TE101 and TE102 modes have been utilized for the realization of quasi elliptic band pass filter response. Sensitivity analysis for dimensional tolerances in resonator dimensions is presented.
{"title":"Design of a Q-band Quasi-elliptic E-plane Filter based on Liquid Crystal Polymer","authors":"Nishant Shukla, Vikas Gupta, P. Ambati","doi":"10.1109/imarc49196.2021.9714651","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714651","url":null,"abstract":"A Q-band 4-pole quasi elliptic E-plane waveguide filter is designed and simulated. Filter circuit is based on liquid crystal polymer substrate so that the better fabrication tolerances can be achieved through lithography at Q-band frequency along with thermal control that liquid crystal polymers can provide due to the availability of broad range of material thermal coefficient of expansion (TCE). TE101 and TE102 modes have been utilized for the realization of quasi elliptic band pass filter response. Sensitivity analysis for dimensional tolerances in resonator dimensions is presented.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121731091","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714683
Antaryami Panigrahi, T. Nath, Subham Chourasia, Shiwam Gupta, Digantar Paul
In this work an all pMOS RF-DC power harvester optimized RF energy harvesting applications is presented. The proposed work is optimised for enhanced sensitivity with an L-match network for GSM band driving the cross coupled pMOS based rectifier, where these transistors operate in the weak inversion region. The rectifier performance is tested using simulation in 180nm CMOS technology for varying received power levels. The rectifier achieves an power conversion efficiency (PCE) of 43.15% and voltage conversion efficiency of 68.5% across load $10kOmega$.
{"title":"A CMOS RF-DC Converter in the GSM Band for RF Energy Harvesting Applications","authors":"Antaryami Panigrahi, T. Nath, Subham Chourasia, Shiwam Gupta, Digantar Paul","doi":"10.1109/imarc49196.2021.9714683","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714683","url":null,"abstract":"In this work an all pMOS RF-DC power harvester optimized RF energy harvesting applications is presented. The proposed work is optimised for enhanced sensitivity with an L-match network for GSM band driving the cross coupled pMOS based rectifier, where these transistors operate in the weak inversion region. The rectifier performance is tested using simulation in 180nm CMOS technology for varying received power levels. The rectifier achieves an power conversion efficiency (PCE) of 43.15% and voltage conversion efficiency of 68.5% across load $10kOmega$.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127526566","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714695
J. C. Dash, D. Sarkar
In this paper, the effect of car bumper permittivity variation on automotive MIMO RADAR antenna array is critically examined using metrics like bi-directional loss model and antenna array ambiguity function. First, a MIMO RADAR with two transmit and four receive antennas is designed and placed behind a simplified curved bumper CAD model. Next, the BLM as well as the AAAF for the antenna-bumper system is computed using the virtual array pattern approach. The proposed analysis provides quantitative insights into the effects on MIMO RADAR performance metrics like field-of-view, angular resolution and ambiguity in direction-of-arrival estimation, caused by real-life antenna-bumper interactions.
{"title":"Impacts on Automotive MIMO RADAR Performance due to Permittivity Variation of Bumper Material: Insights through Bi-directional Loss and Antenna Array Ambiguity Function","authors":"J. C. Dash, D. Sarkar","doi":"10.1109/imarc49196.2021.9714695","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714695","url":null,"abstract":"In this paper, the effect of car bumper permittivity variation on automotive MIMO RADAR antenna array is critically examined using metrics like bi-directional loss model and antenna array ambiguity function. First, a MIMO RADAR with two transmit and four receive antennas is designed and placed behind a simplified curved bumper CAD model. Next, the BLM as well as the AAAF for the antenna-bumper system is computed using the virtual array pattern approach. The proposed analysis provides quantitative insights into the effects on MIMO RADAR performance metrics like field-of-view, angular resolution and ambiguity in direction-of-arrival estimation, caused by real-life antenna-bumper interactions.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116580400","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714640
Alen Joe Antony, A. Anjay Sudesh, Anu Mohamed, R. Gopika, Arijit Mitra, D. Sarkar, C. Saha
In this paper, a variable phase shifter with 360° continuous phase shift range for the X-band phased array applications is presented. The system consists of a branchline coupler, a pair of variable reflection loads using varactor diodes and a switched line topology. The proposed reflective loads result in compact design and require only one control voltage for the varactors which results in simplified control circuit. An algorithm for the control circuit to predict the bias voltage for the required beam steering is also presented. This was further verified by designing and simulating a 4x4 antenna array in Ansys HFSS. The proposed phase shifter achieves an average insertion loss of 4.6 dB and return losses better than 12 dB at 10 GHz with a fractional bandwidth above 15% in simulation.
{"title":"Design of a 360° Continuously Variable Phase Shifter using Improved Regression Algorithm for X-band Phased Array Applications","authors":"Alen Joe Antony, A. Anjay Sudesh, Anu Mohamed, R. Gopika, Arijit Mitra, D. Sarkar, C. Saha","doi":"10.1109/imarc49196.2021.9714640","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714640","url":null,"abstract":"In this paper, a variable phase shifter with 360° continuous phase shift range for the X-band phased array applications is presented. The system consists of a branchline coupler, a pair of variable reflection loads using varactor diodes and a switched line topology. The proposed reflective loads result in compact design and require only one control voltage for the varactors which results in simplified control circuit. An algorithm for the control circuit to predict the bias voltage for the required beam steering is also presented. This was further verified by designing and simulating a 4x4 antenna array in Ansys HFSS. The proposed phase shifter achieves an average insertion loss of 4.6 dB and return losses better than 12 dB at 10 GHz with a fractional bandwidth above 15% in simulation.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124366278","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714636
Shruti Sinha, C. Rao, J. Dhar, R. Jyoti
This paper presents design and test results of compact monolithic 6-bit digital phase shifter (DPS) at S-band for radar applications. The optimum design topology of each bit is selected based on insertion loss, amplitude and phase errors and compactness. The phase shifter is fabricated using $0.25 mu mathrm{m}$ p-HEMT GaAs process from UMS foundry. The developed DPS is realized within the footprint of $4.8 mathrm{~mm} times 2.6 mathrm{~mm} times 0.1 mathrm{~mm}$, exhibits $6.0 mathrm{~dB}$ insertion loss with salient features of voltage wave standing ratio of less than 1.57, RMS amplitude error less than $0.30 mathrm{~dB}$ and RMS phase error better than 1° at 3.2GHz with 100 MHz bandwidth.
{"title":"S band Six-bit Digital Phase Shifter for RADAR applications","authors":"Shruti Sinha, C. Rao, J. Dhar, R. Jyoti","doi":"10.1109/imarc49196.2021.9714636","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714636","url":null,"abstract":"This paper presents design and test results of compact monolithic 6-bit digital phase shifter (DPS) at S-band for radar applications. The optimum design topology of each bit is selected based on insertion loss, amplitude and phase errors and compactness. The phase shifter is fabricated using $0.25 mu mathrm{m}$ p-HEMT GaAs process from UMS foundry. The developed DPS is realized within the footprint of $4.8 mathrm{~mm} times 2.6 mathrm{~mm} times 0.1 mathrm{~mm}$, exhibits $6.0 mathrm{~dB}$ insertion loss with salient features of voltage wave standing ratio of less than 1.57, RMS amplitude error less than $0.30 mathrm{~dB}$ and RMS phase error better than 1° at 3.2GHz with 100 MHz bandwidth.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132460893","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714562
Biswajit Pal, M. Mandal, M. Kahar, S. Dwari
This paper presents a design of a filtering attenuator. Conventional microstrip line resonators of a bandpass filter are loaded with PIN diodes and the resultant component provides band selectivity as well as electronically tunable attenuation. The diode is used as a variable resistor. Detail design steps are provided. A prototype filtering attenuator is fabricated to validate the theoretical approach. It provides an equal ripple bandwidth of 17% at 2.4GHz. The bandwidth can be changed according to application requirement. Hairpin resonators are used for the implementation. Measurement results show that the passband insertion loss of the filtering attenuator can be tuned over 3.8-30.4 dB maintaining a minimum return loss of 10dB.
{"title":"Filtering Attenuator with Electronically Tunable Attenuation","authors":"Biswajit Pal, M. Mandal, M. Kahar, S. Dwari","doi":"10.1109/imarc49196.2021.9714562","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714562","url":null,"abstract":"This paper presents a design of a filtering attenuator. Conventional microstrip line resonators of a bandpass filter are loaded with PIN diodes and the resultant component provides band selectivity as well as electronically tunable attenuation. The diode is used as a variable resistor. Detail design steps are provided. A prototype filtering attenuator is fabricated to validate the theoretical approach. It provides an equal ripple bandwidth of 17% at 2.4GHz. The bandwidth can be changed according to application requirement. Hairpin resonators are used for the implementation. Measurement results show that the passband insertion loss of the filtering attenuator can be tuned over 3.8-30.4 dB maintaining a minimum return loss of 10dB.","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130462307","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}
Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714589
Virendra Kumar, R. Verma, U. S. Pandey, K. S. Beenamole, R. Gangwar
This paper provides insight into the thermal drift in insertion characteristics of the T/R module and its effect on the radiation performance of an active phased array antenna. An efficient liquid-cooled heat exchanger plate is considered to achieve thermal equilibrium in an active phased array antenna to maintain its radiation performance. Herein, a theoretical investigation is carried out to quantify degradation in radiation performance due to change in complex excitation of radiation element at high temperature. This analysis provides theoretical guidelines for the reliable operation of active phased array antennas without performance degradation at high temperatures
{"title":"Thermal Equilibrium in T/R Module Operation and Active Phased Array Antenna Calibration","authors":"Virendra Kumar, R. Verma, U. S. Pandey, K. S. Beenamole, R. Gangwar","doi":"10.1109/imarc49196.2021.9714589","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714589","url":null,"abstract":"This paper provides insight into the thermal drift in insertion characteristics of the T/R module and its effect on the radiation performance of an active phased array antenna. An efficient liquid-cooled heat exchanger plate is considered to achieve thermal equilibrium in an active phased array antenna to maintain its radiation performance. Herein, a theoretical investigation is carried out to quantify degradation in radiation performance due to change in complex excitation of radiation element at high temperature. This analysis provides theoretical guidelines for the reliable operation of active phased array antennas without performance degradation at high temperatures","PeriodicalId":226787,"journal":{"name":"2021 IEEE MTT-S International Microwave and RF Conference (IMARC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133194944","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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