Pub Date : 2021-12-17DOI: 10.1109/imarc49196.2021.9714672
Shu Lin, H. Dong, Yang Liu, Xu-yao Zhang, Xingqi Zhang
This paper presents a simulation-based explanation of the mechanism of a micro-coaxial dual-frequency high-gain omnidirectional coaxial collinear (CoCo) antenna in the millimeter-wave band. Firstly, the antenna model is established, and simulation is carried out to extract the amplitude and phase of the current on the surface of the antenna radiator. Then, the dual-frequency and omnidirectional high-gain characteristics of the antenna are analyzed and explained. Finally, the corresponding relationship between the amplitude and phase distribution of the surface current and the dual-frequency characteristics of the antenna is analyzed. The analysis provided in this paper can guide the design of CoCo antennas.
{"title":"A Millimeter-wave Micro-coaxial Dual-frequency High-gain Omnidirectional CoCo Antenna","authors":"Shu Lin, H. Dong, Yang Liu, Xu-yao Zhang, Xingqi Zhang","doi":"10.1109/imarc49196.2021.9714672","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714672","url":null,"abstract":"This paper presents a simulation-based explanation of the mechanism of a micro-coaxial dual-frequency high-gain omnidirectional coaxial collinear (CoCo) antenna in the millimeter-wave band. Firstly, the antenna model is established, and simulation is carried out to extract the amplitude and phase of the current on the surface of the antenna radiator. Then, the dual-frequency and omnidirectional high-gain characteristics of the antenna are analyzed and explained. Finally, the corresponding relationship between the amplitude and phase distribution of the surface current and the dual-frequency characteristics of the antenna is analyzed. The analysis provided in this paper can guide the design of CoCo antennas.","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":"129655239","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/imarc49196.2021.9714626
P. Sharma, N. Gupta
In this paper a flexible microstrip antenna of $30.1 mathrm{~mm} times 30.1 mathrm{~mm}$, using Polydimethylsiloxane (PDMS) and Jean substrate is presented for Ultra-wideband (UWB) applications. The presented antenna design consists of a rectangular patch having two staircase steps of size $2 mathrm{~mm} times 2$ mm, with defected ground plane and two rectangular slots of 2 $mathrm{mm} times 4 mathrm{~mm}$ are used to enhance the performance and to give wideband characteristics. The comparative analysis performed on the proposed antenna structure using Jean and PDMS substrates shows that the PDMS can be a good candidate as a substrate for flexible antennas.
{"title":"Design and Analysis of Polydimethylsiloxane (PDMS) and Jean Substrate based Flexible Antenna for Ultra-wideband Applications","authors":"P. Sharma, N. Gupta","doi":"10.1109/imarc49196.2021.9714626","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714626","url":null,"abstract":"In this paper a flexible microstrip antenna of $30.1 mathrm{~mm} times 30.1 mathrm{~mm}$, using Polydimethylsiloxane (PDMS) and Jean substrate is presented for Ultra-wideband (UWB) applications. The presented antenna design consists of a rectangular patch having two staircase steps of size $2 mathrm{~mm} times 2$ mm, with defected ground plane and two rectangular slots of 2 $mathrm{mm} times 4 mathrm{~mm}$ are used to enhance the performance and to give wideband characteristics. The comparative analysis performed on the proposed antenna structure using Jean and PDMS substrates shows that the PDMS can be a good candidate as a substrate for flexible antennas.","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":"129910473","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/IMaRC49196.2021.9714666
Pratik Ghosh, B. Chaudhury
The 2D simulations of HPM breakdown induced plasma formation in the context of applications such as HPM switching and power limiter for protection of electronic components presented. Breakdown thresholds, the field strength and the initial plasma density that determines breakdown time are reported. The dependence of cutoff time on initial plasma as well as strength of microwave E-field are reported. The transmission and rejection capability of plasma for certain frequency is shown. Further, variations in permittivity and conductivity of breakdown plasma also studied. Study also highlights the importance of correct choice of diffusion coefficient in the given fluid-based model.
{"title":"Computational Investigation of Microwave Breakdown in HPM Switching and Protection","authors":"Pratik Ghosh, B. Chaudhury","doi":"10.1109/IMaRC49196.2021.9714666","DOIUrl":"https://doi.org/10.1109/IMaRC49196.2021.9714666","url":null,"abstract":"The 2D simulations of HPM breakdown induced plasma formation in the context of applications such as HPM switching and power limiter for protection of electronic components presented. Breakdown thresholds, the field strength and the initial plasma density that determines breakdown time are reported. The dependence of cutoff time on initial plasma as well as strength of microwave E-field are reported. The transmission and rejection capability of plasma for certain frequency is shown. Further, variations in permittivity and conductivity of breakdown plasma also studied. Study also highlights the importance of correct choice of diffusion coefficient in the given fluid-based model.","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":"130206253","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/imarc49196.2021.9714700
M. Bhavsar, Puja Srivastava, D. Singh, K. Parikh
This paper presents the design and measured performance of a novel 20.5-25.5GHz 8-Watt Power Amplifier (PA) Monolithic Microwave Integrated Circuit (MMIC). The circuit provides linear gain higher than 20dB, output power of 8-Watt and Power Added Efficiency (PAE) better than 30% over the band. The MMIC is designed using $0.15mu m$ GaN highelectron mobility transistor (HEMT) based GH15 process from UMS foundry. Two identical amplifiers are designed except different output power matching networks (OMN) to better understand effectiveness of novel OMN presented in the paper. Novel output power matching circuit used in the power amplifier adds minimum loss and reduces the spread of output impedance over the frequency to obtain output power, PAE and output matching over wider band. Total four HEMTs of size $75 mu m x 8$ are combined at final output stage to obtain desired output power. Transformation of output impedance from single point 50Ohm to required impedance for optimum PAE for HEMT is discussed in detail using smith chart showing contribution of each matching element.
本文介绍了一种新型的20.5-25.5GHz 8瓦功率放大器(PA)单片微波集成电路(MMIC)的设计和性能测试。该电路的线性增益高于20dB，输出功率为8瓦，功率附加效率(PAE)在该频段内优于30%。MMIC采用UMS代工公司基于GH15工艺的0.15 μ m$ GaN高电子迁移率晶体管(HEMT)设计。为了更好地理解本文提出的新型输出功率匹配网络的有效性，除了不同的输出功率匹配网络外，还设计了两个相同的放大器。在功率放大器中采用了新颖的输出功率匹配电路，使损耗最小，减少了输出阻抗在频率上的扩散，从而获得更宽频带的输出功率、PAE和输出匹配。在最终输出阶段，总共四个尺寸为$75 μ m x 8$的hemt组合在一起以获得所需的输出功率。用史密斯图详细讨论了输出阻抗从单点50欧姆到HEMT最佳PAE所需阻抗的转换，史密斯图显示了每个匹配元件的贡献。
{"title":"K-Band 8-Watt Power Amplifier MMICs using 150nm GaN process for Satellite Transponder","authors":"M. Bhavsar, Puja Srivastava, D. Singh, K. Parikh","doi":"10.1109/imarc49196.2021.9714700","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714700","url":null,"abstract":"This paper presents the design and measured performance of a novel 20.5-25.5GHz 8-Watt Power Amplifier (PA) Monolithic Microwave Integrated Circuit (MMIC). The circuit provides linear gain higher than 20dB, output power of 8-Watt and Power Added Efficiency (PAE) better than 30% over the band. The MMIC is designed using $0.15mu m$ GaN highelectron mobility transistor (HEMT) based GH15 process from UMS foundry. Two identical amplifiers are designed except different output power matching networks (OMN) to better understand effectiveness of novel OMN presented in the paper. Novel output power matching circuit used in the power amplifier adds minimum loss and reduces the spread of output impedance over the frequency to obtain output power, PAE and output matching over wider band. Total four HEMTs of size $75 mu m x 8$ are combined at final output stage to obtain desired output power. Transformation of output impedance from single point 50Ohm to required impedance for optimum PAE for HEMT is discussed in detail using smith chart showing contribution of each matching element.","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":"121677318","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/imarc49196.2021.9714707
Gouri Sharma, Anshul Gupta
A four-port cylindrical dielectric resonator antenna (CDRA) for WLAN/WiMAX has been described in this letter. Four cylindrical dielectric resonator antennas are placed on the upper part of the substrate and are fed with an aid of a rectangular aperture such that any two adjacent radiating antennas are orthogonal to each other. The antenna works in the frequency range of 5.03 to 5.92GHz. At the resonant frequency, the reduced mutual coupling is depicted to be better than -30dB. The diversity performance of the stated radiator is also found within optimal limits.
{"title":"Four Port Multiple Input Multiple Output DRA for WLAN/WiMAX Applications","authors":"Gouri Sharma, Anshul Gupta","doi":"10.1109/imarc49196.2021.9714707","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714707","url":null,"abstract":"A four-port cylindrical dielectric resonator antenna (CDRA) for WLAN/WiMAX has been described in this letter. Four cylindrical dielectric resonator antennas are placed on the upper part of the substrate and are fed with an aid of a rectangular aperture such that any two adjacent radiating antennas are orthogonal to each other. The antenna works in the frequency range of 5.03 to 5.92GHz. At the resonant frequency, the reduced mutual coupling is depicted to be better than -30dB. The diversity performance of the stated radiator is also found within optimal limits.","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":"125116394","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/imarc49196.2021.9714575
N. Gupta, H. Wanare, Gaganpreet Singh, J. Ramkumar, K. V. Srivastava, S. A. Ramakrishna
We have designed and experimentally realized an optically transparent, broadband, and polarization-insensitive metastructure. The proposed metastructure demonstrates farfield radiation management capabilities in widely separated electromagnetic regimes, namely, near-perfect absorption of farfield radiation at microwave frequencies and curated emission at infirared wavelengths. The metastructure provides a functional alternative to the hierarchical designs of radar-infrared bi-stealth as it accommodates the contrasting multispectral functionalities in a consolidated configuration. Furthermore, we also look beyond the notions of perfect absorption and highlight the prospects of arbitrarily large power absorption using evanescent fields, provided that we make a transition to the conjugate impedance matching condition.
{"title":"Multispectral Non-Hierarchical Metastructures for Radiation Management and Limits of Perfect Absorption","authors":"N. Gupta, H. Wanare, Gaganpreet Singh, J. Ramkumar, K. V. Srivastava, S. A. Ramakrishna","doi":"10.1109/imarc49196.2021.9714575","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714575","url":null,"abstract":"We have designed and experimentally realized an optically transparent, broadband, and polarization-insensitive metastructure. The proposed metastructure demonstrates farfield radiation management capabilities in widely separated electromagnetic regimes, namely, near-perfect absorption of farfield radiation at microwave frequencies and curated emission at infirared wavelengths. The metastructure provides a functional alternative to the hierarchical designs of radar-infrared bi-stealth as it accommodates the contrasting multispectral functionalities in a consolidated configuration. Furthermore, we also look beyond the notions of perfect absorption and highlight the prospects of arbitrarily large power absorption using evanescent fields, provided that we make a transition to the conjugate impedance matching condition.","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":"130521617","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/imarc49196.2021.9714701
K. K. Ansha, P. Abdulla, P. M. Jasmine
this paper presents the design of split ring circular slot arrays on the broad wall of the WR3 waveguide for the SubTHz applications. The proposed antenna covers an impedance bandwidth of 88GHz at -10 dB ranging from 244GHz to 332 GHz with a maximum gain of 15.3dBi and 3dB axial ratio bandwidth of 35.71GHz spanning from 251.72GHz to 287.51 GHz. All simulations are done in the CST microwave suite and the results are validated in HFSS software.
{"title":"Split Ring Circular Slot Arrays on WR3 Waveguide for Sub-THz Applications","authors":"K. K. Ansha, P. Abdulla, P. M. Jasmine","doi":"10.1109/imarc49196.2021.9714701","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714701","url":null,"abstract":"this paper presents the design of split ring circular slot arrays on the broad wall of the WR3 waveguide for the SubTHz applications. The proposed antenna covers an impedance bandwidth of 88GHz at -10 dB ranging from 244GHz to 332 GHz with a maximum gain of 15.3dBi and 3dB axial ratio bandwidth of 35.71GHz spanning from 251.72GHz to 287.51 GHz. All simulations are done in the CST microwave suite and the results are validated in HFSS software.","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":"116688230","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/imarc49196.2021.9714621
Sanjeev Kumar, S. Chatterjee, S. Koul
This paper presents Gm boosted CG-CS low power, high gain LNA for 5G applications. The LNA is cascaded with a CG cascoded stage and CS cascoded stage. In the first stage, a transformer-based gm boosting technique has been used along with series peaking. The second stage is used for increasing the gain in total. The $65 mathrm{~nm}$ CMOS process is used for simulations. The LNA simulations show a gain of $22 mathrm{~dB}$ and a noise Figure of $3.5 mathrm{~dB}$ with a $-3 mathrm{~dB}$ bandwidth of 6.7 GHz. The minimum NF obtained is $3.4 mathrm{~dB}$ at 38 GHz and is below $4 mathrm{~dB}$ from 33 GHz to 41 GHz. The proposed LNA consumes only $3.5 mathrm{~mW}$ from a 1-V supply.
{"title":"A 36 GHz Low Power LNA Using Gm-Boosting Technique","authors":"Sanjeev Kumar, S. Chatterjee, S. Koul","doi":"10.1109/imarc49196.2021.9714621","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714621","url":null,"abstract":"This paper presents Gm boosted CG-CS low power, high gain LNA for 5G applications. The LNA is cascaded with a CG cascoded stage and CS cascoded stage. In the first stage, a transformer-based gm boosting technique has been used along with series peaking. The second stage is used for increasing the gain in total. The $65 mathrm{~nm}$ CMOS process is used for simulations. The LNA simulations show a gain of $22 mathrm{~dB}$ and a noise Figure of $3.5 mathrm{~dB}$ with a $-3 mathrm{~dB}$ bandwidth of 6.7 GHz. The minimum NF obtained is $3.4 mathrm{~dB}$ at 38 GHz and is below $4 mathrm{~dB}$ from 33 GHz to 41 GHz. The proposed LNA consumes only $3.5 mathrm{~mW}$ from a 1-V supply.","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":"116839776","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/imarc49196.2021.9714699
Nhu-Huan Nguyen, A. Ghiotto, A. Vilcot, T. Vuong, Ke Wu
This paper presents a broadband AFSIW termination for applications in Ka-band (26.5GHz to 40GHz). Using a surface mounted absorbing material, this solution is found to be not sensitive to the dimension and position of the absorber, which enables mass-production capability. Measurement results validate the broadband response over the entire Ka-band. This novel AFSIW termination completes the library of available AFSIW components and contributes to paving the way towards the design of high-performance systems on substrate (SoS).
{"title":"Mass-Producible Broadband AFSIW Termination","authors":"Nhu-Huan Nguyen, A. Ghiotto, A. Vilcot, T. Vuong, Ke Wu","doi":"10.1109/imarc49196.2021.9714699","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714699","url":null,"abstract":"This paper presents a broadband AFSIW termination for applications in Ka-band (26.5GHz to 40GHz). Using a surface mounted absorbing material, this solution is found to be not sensitive to the dimension and position of the absorber, which enables mass-production capability. Measurement results validate the broadband response over the entire Ka-band. This novel AFSIW termination completes the library of available AFSIW components and contributes to paving the way towards the design of high-performance systems on substrate (SoS).","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":"116925421","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/imarc49196.2021.9714583
Anirudh Kumar, Priyanka Pai, V. Kavitha, S. Prashanth
This paper presents the design features, simulation & implementation of a X-band Pulsed Power Amplifier and down converter using double down conversion technique in a single mechanical housing. This module has been designed & tested for various features like high output power, high gain in PA section & low noise figure, excellent image rejection, high gain, MSTC, AGC & BITE check in Down converter section. Module is designed, fabricated & tested successfully and is meeting all the required specifications. A close match is achieved between the simulated & tested results. Mean Time Between Failure (MTBF) is predicted to be 13530Hrs.
{"title":"Design of X-Band Pulsed Power Amplifier & Downconverter","authors":"Anirudh Kumar, Priyanka Pai, V. Kavitha, S. Prashanth","doi":"10.1109/imarc49196.2021.9714583","DOIUrl":"https://doi.org/10.1109/imarc49196.2021.9714583","url":null,"abstract":"This paper presents the design features, simulation & implementation of a X-band Pulsed Power Amplifier and down converter using double down conversion technique in a single mechanical housing. This module has been designed & tested for various features like high output power, high gain in PA section & low noise figure, excellent image rejection, high gain, MSTC, AGC & BITE check in Down converter section. Module is designed, fabricated & tested successfully and is meeting all the required specifications. A close match is achieved between the simulated & tested results. Mean Time Between Failure (MTBF) is predicted to be 13530Hrs.","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":"134518879","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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