Pub Date : 2017-04-20DOI: 10.1109/INMMIC.2017.7927301
T. Johansen, V. Midili, M. Squartecchia, V. Zhurbenko, V. Nodjiadjim, J. Dupuy, M. Riet, A. Konczykowska
A large-signal modeling approach has been developed for multi-finger devices fabricated in an Indium Phosphide (InP) Double Heterojunction Bipolar Transistor (DHBT) process. The approach utilizes unit-finger device models embedded in a multi-port parasitic network. The unit-finger model is based on an improved UCSD HBT model formulation avoiding an erroneous RciCbci transit-time contribution from the intrinsic collector region as found in other III-V based HBT models. The mutual heating between fingers is modeled by a thermal coupling network with parameters extracted from electro-thermal simulations. The multi-finger modeling approach is verified against measurements on an 84 GHz power amplifier utilizing four finger InP DHBTs in a stacked configuration.
{"title":"Large-signal modeling of multi-finger InP DHBT devices at millimeter-wave frequencies","authors":"T. Johansen, V. Midili, M. Squartecchia, V. Zhurbenko, V. Nodjiadjim, J. Dupuy, M. Riet, A. Konczykowska","doi":"10.1109/INMMIC.2017.7927301","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927301","url":null,"abstract":"A large-signal modeling approach has been developed for multi-finger devices fabricated in an Indium Phosphide (InP) Double Heterojunction Bipolar Transistor (DHBT) process. The approach utilizes unit-finger device models embedded in a multi-port parasitic network. The unit-finger model is based on an improved UCSD HBT model formulation avoiding an erroneous RciCbci transit-time contribution from the intrinsic collector region as found in other III-V based HBT models. The mutual heating between fingers is modeled by a thermal coupling network with parameters extracted from electro-thermal simulations. The multi-finger modeling approach is verified against measurements on an 84 GHz power amplifier utilizing four finger InP DHBTs in a stacked configuration.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117263593","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 : 2017-04-20DOI: 10.1109/INMMIC.2017.7927304
L. Pantoli, V. Stornelli, G. Leuzzi, L. HongJun, Hu Zhifu
In this work we present a pHMET single chip integrated active filter for high performances RF applications. The filter is based on a high-Q active inductor (AI) and is designed by the use of a single transistor for each resonator cell and a compensation net-work that allows controlling both the inductance value and its series resistance. The filter has been optimised for operating between 1800 MHz and 2100 MHz with a narrow 3 dB bandwidth of 30 MHz and a rejection ratio of 30dB at 30 MHz from the center frequency. The −8 dBm P1dB compression point and a dynamic range of 75 dB are obtained with a DC power consumption of 120 mW.
{"title":"GaAs MMIC tunable active filter","authors":"L. Pantoli, V. Stornelli, G. Leuzzi, L. HongJun, Hu Zhifu","doi":"10.1109/INMMIC.2017.7927304","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927304","url":null,"abstract":"In this work we present a pHMET single chip integrated active filter for high performances RF applications. The filter is based on a high-Q active inductor (AI) and is designed by the use of a single transistor for each resonator cell and a compensation net-work that allows controlling both the inductance value and its series resistance. The filter has been optimised for operating between 1800 MHz and 2100 MHz with a narrow 3 dB bandwidth of 30 MHz and a rejection ratio of 30dB at 30 MHz from the center frequency. The −8 dBm P1dB compression point and a dynamic range of 75 dB are obtained with a DC power consumption of 120 mW.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123955627","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 : 2017-04-01DOI: 10.1109/INMMIC.2017.7927302
Francesco Trevisan, A. Raffo, G. Bosi, V. Vadalà, G. Vannini, G. Formicone, J. Burger, J. Custer
In this paper an automated measurement system for the investigation of degradation phenomena in GaN FETs is presented. The system is able to perform both static and dynamic stress cycles under actual device operation, gathering useful information strictly related to the “health” of the device. As case study a 75-VDC GaN HEMT was used for a 19-hours stress test, putting in evidence how the device performance slightly degrades during the stress experiment.
本文介绍了一种用于研究氮化镓场效应管中降解现象的自动测量系统。该系统能够在实际设备操作下执行静态和动态应力循环，收集与设备“健康”严格相关的有用信息。作为案例研究，使用75-VDC GaN HEMT进行了19小时的压力测试，证明了在压力实验中设备性能略有下降。
{"title":"75-VDC GaN technology investigation from a degradation perspective","authors":"Francesco Trevisan, A. Raffo, G. Bosi, V. Vadalà, G. Vannini, G. Formicone, J. Burger, J. Custer","doi":"10.1109/INMMIC.2017.7927302","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927302","url":null,"abstract":"In this paper an automated measurement system for the investigation of degradation phenomena in GaN FETs is presented. The system is able to perform both static and dynamic stress cycles under actual device operation, gathering useful information strictly related to the “health” of the device. As case study a 75-VDC GaN HEMT was used for a 19-hours stress test, putting in evidence how the device performance slightly degrades during the stress experiment.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124233530","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 : 2017-04-01DOI: 10.1109/INMMIC.2017.7927307
N. Leder, B. Pichler, G. Magerl, H. Arthaber
All-digital radio frequency transmitters (DRFTx) offer many potential benefits for future RF applications. However, their design requires the use of nonlinear models that can describe the memory induced, nonlinear behavior of these circuits. The model needs to cover a huge bandwidth and incorporate the behavior of the digital-analog-converter within the DRFTx. Gaining highly synchronous recordings from such a mixed signal RF circuit, which is required for modeling and verification, is a demanding task. This paper demonstrates how a correlative multistage synchronization can be used to synchronize such measurements. It also demonstrates how sensitive the uncompensated normalized mean square error (NMSE) is to timing offsets when comparing signal from different recordings and how time-frequency methods can be used to gain more robust error measures through delay tracking and compensation.
{"title":"Delay compensation and tracking for all-digital RF-transmitter models","authors":"N. Leder, B. Pichler, G. Magerl, H. Arthaber","doi":"10.1109/INMMIC.2017.7927307","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927307","url":null,"abstract":"All-digital radio frequency transmitters (DRFTx) offer many potential benefits for future RF applications. However, their design requires the use of nonlinear models that can describe the memory induced, nonlinear behavior of these circuits. The model needs to cover a huge bandwidth and incorporate the behavior of the digital-analog-converter within the DRFTx. Gaining highly synchronous recordings from such a mixed signal RF circuit, which is required for modeling and verification, is a demanding task. This paper demonstrates how a correlative multistage synchronization can be used to synchronize such measurements. It also demonstrates how sensitive the uncompensated normalized mean square error (NMSE) is to timing offsets when comparing signal from different recordings and how time-frequency methods can be used to gain more robust error measures through delay tracking and compensation.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132711505","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 : 2017-04-01DOI: 10.1109/INMMIC.2017.7927309
E. Auerbach, N. Leder, S. Gider, D. Suess, H. Arthaber
The MgO-based magnetic tunnel junction (MTJ) is the basis of modern hard disk drives' magnetic read sensors. Within its operating bandwidth, the sensor's performance is significantly affected by nonlinear and oscillating behavior arising from the MTJ's magnetization dynamics at microwave frequencies. Static I-V curve measurements are commonly used to characterize sensor's nonlinear effects. Unfortunately, these do not sufficiently capture the MTJ's magnetization dynamics. In this paper, we demonstrate the use of the two-tone measurement technique for full treatment of the sensor's nonlinear effects in conjunction with dynamic ones. This approach is new in the field of magnetism and magnetic materials, and it has its challenges due to the nature of the device. Nevertheless, the experimental results demonstrate how the two-tone measurement technique can be used to characterize magnetic sensor nonlinear properties.
{"title":"Characterization of dynamic nonlinear effects in MTJ-based magnetic sensors","authors":"E. Auerbach, N. Leder, S. Gider, D. Suess, H. Arthaber","doi":"10.1109/INMMIC.2017.7927309","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927309","url":null,"abstract":"The MgO-based magnetic tunnel junction (MTJ) is the basis of modern hard disk drives' magnetic read sensors. Within its operating bandwidth, the sensor's performance is significantly affected by nonlinear and oscillating behavior arising from the MTJ's magnetization dynamics at microwave frequencies. Static I-V curve measurements are commonly used to characterize sensor's nonlinear effects. Unfortunately, these do not sufficiently capture the MTJ's magnetization dynamics. In this paper, we demonstrate the use of the two-tone measurement technique for full treatment of the sensor's nonlinear effects in conjunction with dynamic ones. This approach is new in the field of magnetism and magnetic materials, and it has its challenges due to the nature of the device. Nevertheless, the experimental results demonstrate how the two-tone measurement technique can be used to characterize magnetic sensor nonlinear properties.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124914123","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 : 2017-04-01DOI: 10.1109/INMMIC.2017.7927312
J. King, T. Brazil
This paper presents a simple and accurate extension of Vector Fitting for the inclusion of bandpass linear time invariant (LTI) frequency-domain data within a nonlinear baseband time domain simulation. The time-domain response is obtained as a complex-valued sum of decaying exponentials, which may be then convolved with the complex baseband form of the input signal to obtain the corresponding complex baseband output. This allows networks which are most accurately described in the frequency domain, such as frequency-dispersive transmission lines, to be included as part of a general time-domain nonlinear circuit solver. While the method is general, this contribution utilises bandpass frequency-domain data in the form of network scattering parameters.
{"title":"Time-domain simulation of passband S-parameter networks using complex baseband vector fitting","authors":"J. King, T. Brazil","doi":"10.1109/INMMIC.2017.7927312","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927312","url":null,"abstract":"This paper presents a simple and accurate extension of Vector Fitting for the inclusion of bandpass linear time invariant (LTI) frequency-domain data within a nonlinear baseband time domain simulation. The time-domain response is obtained as a complex-valued sum of decaying exponentials, which may be then convolved with the complex baseband form of the input signal to obtain the corresponding complex baseband output. This allows networks which are most accurately described in the frequency domain, such as frequency-dispersive transmission lines, to be included as part of a general time-domain nonlinear circuit solver. While the method is general, this contribution utilises bandpass frequency-domain data in the form of network scattering parameters.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131028069","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 : 2017-04-01DOI: 10.1109/INMMIC.2017.7927314
C. Fager, Katharina Hausmair, K. Buisman, K. Andersson, Esther Sienkiewicz, D. Gustafsson
This paper investigates nonlinear distortion effects in active antenna phased array transmitters. Using a nonlinear modeling technique, the joint interactions between power amplifiers and antennas are investigated in detail. Numerical simulations based on a 28 GHz GaN MMIC PA and a 64-element antenna array are used to exemplify the use of the proposed technique in a typical 5G application. The results show that the antenna mutual coupling will cause the individual PA compression characteristics and hence the far field distortion to depend significantly on beam steer angle.
研究了有源天线相控阵发射机的非线性畸变效应。利用非线性建模技术，详细研究了功率放大器与天线之间的联合相互作用。基于28 GHz GaN MMIC PA和64元天线阵列的数值模拟用于举例说明所提出的技术在典型5G应用中的使用。结果表明，天线的相互耦合将导致各个声源的压缩特性，从而导致远场畸变显著依赖于波束转向角。
{"title":"Analysis of nonlinear distortion in phased array transmitters","authors":"C. Fager, Katharina Hausmair, K. Buisman, K. Andersson, Esther Sienkiewicz, D. Gustafsson","doi":"10.1109/INMMIC.2017.7927314","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927314","url":null,"abstract":"This paper investigates nonlinear distortion effects in active antenna phased array transmitters. Using a nonlinear modeling technique, the joint interactions between power amplifiers and antennas are investigated in detail. Numerical simulations based on a 28 GHz GaN MMIC PA and a 64-element antenna array are used to exemplify the use of the proposed technique in a typical 5G application. The results show that the antenna mutual coupling will cause the individual PA compression characteristics and hence the far field distortion to depend significantly on beam steer angle.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133771852","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 : 2017-04-01DOI: 10.1109/INMMIC.2017.7927300
A. M. Bughio, S. Guerrieri, F. Bonani, G. Ghione
FinFETs operated with varying bias, and in particular with Short-circuited Gates (SG) or Independent Gates (IG), are actively investigated for RF analog applications. The device process variability is known to vary, at least for DC performances, according to the FINFET bias. This paper presents a novel, comprehensive physics-based variability analysis focused on AC parameters for a double-gate (DG) MOSFET (FinFET) both in SG and IG conditions. The analysis is carried out with a numerically efficient Green's Function technique [1], [2], that exploits a nonlinear variability analysis tool in quasi-linear condition. The AC variability analysis of the FinFET includes selected geometrical and physical parameters, such as the fin width, the source/drain-gate distance and the doping level, whose role is especially relevant for the extraction of the device parasitics' variations. We demonstrate that the sensitivity of the AC parameters differs in the IG and SG case, especially concerning gate capacitances.
{"title":"Physics-based modeling of FinFET RF variability under Shorted- and Independent-Gates bias","authors":"A. M. Bughio, S. Guerrieri, F. Bonani, G. Ghione","doi":"10.1109/INMMIC.2017.7927300","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927300","url":null,"abstract":"FinFETs operated with varying bias, and in particular with Short-circuited Gates (SG) or Independent Gates (IG), are actively investigated for RF analog applications. The device process variability is known to vary, at least for DC performances, according to the FINFET bias. This paper presents a novel, comprehensive physics-based variability analysis focused on AC parameters for a double-gate (DG) MOSFET (FinFET) both in SG and IG conditions. The analysis is carried out with a numerically efficient Green's Function technique [1], [2], that exploits a nonlinear variability analysis tool in quasi-linear condition. The AC variability analysis of the FinFET includes selected geometrical and physical parameters, such as the fin width, the source/drain-gate distance and the doping level, whose role is especially relevant for the extraction of the device parasitics' variations. We demonstrate that the sensitivity of the AC parameters differs in the IG and SG case, especially concerning gate capacitances.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"155 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126823340","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 : 2017-04-01DOI: 10.1109/INMMIC.2017.7927311
V. Camarchia, R. Quaglia, C. Ramella, M. Pirola
This paper presents three power amplifiers designed for 15 GHz microwave radio application employing GaN 0.25 μm technology. The first design is a 3W combined power amplifier, the second is a 7–15 GHz dual-band 3 W combined power amplifier, and the third is a 4W Doherty power amplifier. Advantages and limitations of GaN 0.25 μm technology applied to the three different design solutions for this specific application are discussed, presenting and comparing the measurement results obtained on the developed amplifiers.
{"title":"Power amplifier MMICs for 15 GHz microwave links in 0.25 üm GaN technology","authors":"V. Camarchia, R. Quaglia, C. Ramella, M. Pirola","doi":"10.1109/INMMIC.2017.7927311","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927311","url":null,"abstract":"This paper presents three power amplifiers designed for 15 GHz microwave radio application employing GaN 0.25 μm technology. The first design is a 3W combined power amplifier, the second is a 7–15 GHz dual-band 3 W combined power amplifier, and the third is a 4W Doherty power amplifier. Advantages and limitations of GaN 0.25 μm technology applied to the three different design solutions for this specific application are discussed, presenting and comparing the measurement results obtained on the developed amplifiers.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122354270","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 : 2017-04-01DOI: 10.1109/INMMIC.2017.7927313
G. P. Gibiino, K. Łukasik, P. Barmuta, D. Schreurs, A. Santarelli, F. Filicori
This work proposes a behavioral modeling approach suitable for power amplifier (PA) operation under dynamic load modulation. The model accounts for the PA nonlinear dynamic effects by means of 1st order kernel functions of the modified Volterra formulation, extracted from automated Nonlinear Vector Network Analyzer (NVNA) measurements. Validation experiments under wideband load modulation are reported for a commercial PA concurrently excited by an RF multi-tone at the input, and by another multi-tone actively injected at the output in order to generate a dynamic load. The experiment is performed at 2.4 GHz with 20 MHz bandwidth signals.
{"title":"Behavioral modeling of RF PAs under wideband load modulation","authors":"G. P. Gibiino, K. Łukasik, P. Barmuta, D. Schreurs, A. Santarelli, F. Filicori","doi":"10.1109/INMMIC.2017.7927313","DOIUrl":"https://doi.org/10.1109/INMMIC.2017.7927313","url":null,"abstract":"This work proposes a behavioral modeling approach suitable for power amplifier (PA) operation under dynamic load modulation. The model accounts for the PA nonlinear dynamic effects by means of 1st order kernel functions of the modified Volterra formulation, extracted from automated Nonlinear Vector Network Analyzer (NVNA) measurements. Validation experiments under wideband load modulation are reported for a commercial PA concurrently excited by an RF multi-tone at the input, and by another multi-tone actively injected at the output in order to generate a dynamic load. The experiment is performed at 2.4 GHz with 20 MHz bandwidth signals.","PeriodicalId":322300,"journal":{"name":"2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC)","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128776951","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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