Pub Date : 2011-06-05DOI: 10.1109/MWSYM.2011.5972580
Yuandan Dong, T. Itoh
A novel design concept for compact dual-band substrate integrated waveguide (SIW) filters using the complementary split-ring resonators (CSRRs) is presented. By loading two different types of CSRRs on the waveguide surface, two passbands propagating below the waveguide cutoff frequency are generated separately. The proposed structure allows relatively independent control over the center frequencies and the coupling coefficients. The working principle is illustrated and the filter design methodology is examined. Two two-pole filters with dual-band operation are demonstrated, showing advantages in terms of the compact size, good selectivity and stopband rejection, easy fabrication and integration with other circuits.
{"title":"Miniaturized dual-band substrate integrated waveguide filters using complementary split-ring resonators","authors":"Yuandan Dong, T. Itoh","doi":"10.1109/MWSYM.2011.5972580","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972580","url":null,"abstract":"A novel design concept for compact dual-band substrate integrated waveguide (SIW) filters using the complementary split-ring resonators (CSRRs) is presented. By loading two different types of CSRRs on the waveguide surface, two passbands propagating below the waveguide cutoff frequency are generated separately. The proposed structure allows relatively independent control over the center frequencies and the coupling coefficients. The working principle is illustrated and the filter design methodology is examined. Two two-pole filters with dual-band operation are demonstrated, showing advantages in terms of the compact size, good selectivity and stopband rejection, easy fabrication and integration with other circuits.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122240079","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972562
Min Wang, C. Saavedra
A single-sideband upconverter mixer with sideband selection capability is presented. Sideband selection is accomplished by inverting the polarity of either the I or Q differential IF signals into the upconverter by means of a switch network. The mixer operates at an LO frequency of 5 GHz and an IF of 100 MHz, and thus it produces an upper sideband at 5.1 GHz and a lower sideband at 4.9 GHz. Experimental results show that the mixer has a conversion gain of over 12 dB and that its IP1dB is −12 dBm and its IIP3 is −5 dBm. The OP1dB and OIP3 of the upconverter are 0 dBm and +6.5 dBm, respectively. The chip was fabricated using a standard 130 nm CMOS process, it consumes a total of 26 mW of dc power and the circuit core occupies an area of 0.49 mm2.
{"title":"Fully monolithic single-sideband upconverter mixer with sideband selection","authors":"Min Wang, C. Saavedra","doi":"10.1109/MWSYM.2011.5972562","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972562","url":null,"abstract":"A single-sideband upconverter mixer with sideband selection capability is presented. Sideband selection is accomplished by inverting the polarity of either the I or Q differential IF signals into the upconverter by means of a switch network. The mixer operates at an LO frequency of 5 GHz and an IF of 100 MHz, and thus it produces an upper sideband at 5.1 GHz and a lower sideband at 4.9 GHz. Experimental results show that the mixer has a conversion gain of over 12 dB and that its IP1dB is −12 dBm and its IIP3 is −5 dBm. The OP1dB and OIP3 of the upconverter are 0 dBm and +6.5 dBm, respectively. The chip was fabricated using a standard 130 nm CMOS process, it consumes a total of 26 mW of dc power and the circuit core occupies an area of 0.49 mm2.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125726603","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972639
F. Ferranti, M. Nakhla, G. Antonini, T. Dhaene, L. Knockaert, A. Ruehli
We propose a novel model order reduction technique that is able to accurately reduce electrically large systems with delay elements, which can be described by means of neutral delayed differential equations. It is based on an adaptive multipoint expansion and model order reduction of equivalent first order systems. The neutral delayed differential formulation is preserved in the reduced model. Pertinent numerical results validate the proposed model order reduction approach.
{"title":"Reduced order modeling of delayed PEEC circuits","authors":"F. Ferranti, M. Nakhla, G. Antonini, T. Dhaene, L. Knockaert, A. Ruehli","doi":"10.1109/MWSYM.2011.5972639","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972639","url":null,"abstract":"We propose a novel model order reduction technique that is able to accurately reduce electrically large systems with delay elements, which can be described by means of neutral delayed differential equations. It is based on an adaptive multipoint expansion and model order reduction of equivalent first order systems. The neutral delayed differential formulation is preserved in the reduced model. Pertinent numerical results validate the proposed model order reduction approach.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126083776","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972752
Jun Liu, Lingling Sun, Zhiping Yu, M. Condon
A simple method to determine the power dissipation dependent thermal resistance and the junction temperature of a power AlGaN/GaN HEMT proposed. The method is based on a rigorous mathematical treatment of the nonlinear characteristics of thermal resistance. It is hence suitable for modeling of transistors operating at any power densities. This method has been verified by an accurate predicting of junction temperature of an 8×80µm×0.3µm AlGaN/GaN HEMT, fabricated with an in-house AlGaN/GaN HEMTs technology.
{"title":"A simple method to determine power-dissipation dependent thermal resistance for GaN HEMTs","authors":"Jun Liu, Lingling Sun, Zhiping Yu, M. Condon","doi":"10.1109/MWSYM.2011.5972752","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972752","url":null,"abstract":"A simple method to determine the power dissipation dependent thermal resistance and the junction temperature of a power AlGaN/GaN HEMT proposed. The method is based on a rigorous mathematical treatment of the nonlinear characteristics of thermal resistance. It is hence suitable for modeling of transistors operating at any power densities. This method has been verified by an accurate predicting of junction temperature of an 8×80µm×0.3µm AlGaN/GaN HEMT, fabricated with an in-house AlGaN/GaN HEMTs technology.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"40 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120939959","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972726
R Patil Vijay, D. Slichter, I. Siddiqi
Over the past decade, quantum coherent behavior has been observed in electrical circuits engineered to have discrete, individually addressable energy levels. These devices operate at cryogenic temperatures and microwave frequencies—conditions which permit the utilization of superconducting passive and active resonant circuits for measurement. The basic architecture of a quantum dispersive measurement consisting of a two level quantum bit coupled to a LC tank circuit is reviewed. Recent progress with this type of readout has led to the real time monitoring of a superconducting qubit with the observation of quantum jumps between energy levels.
{"title":"Dispersive microwave readout for quantum electrical circuits","authors":"R Patil Vijay, D. Slichter, I. Siddiqi","doi":"10.1109/MWSYM.2011.5972726","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972726","url":null,"abstract":"Over the past decade, quantum coherent behavior has been observed in electrical circuits engineered to have discrete, individually addressable energy levels. These devices operate at cryogenic temperatures and microwave frequencies—conditions which permit the utilization of superconducting passive and active resonant circuits for measurement. The basic architecture of a quantum dispersive measurement consisting of a two level quantum bit coupled to a LC tank circuit is reviewed. Recent progress with this type of readout has led to the real time monitoring of a superconducting qubit with the observation of quantum jumps between energy levels.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124974176","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972899
T. Villela
In this paper, it is presented a brief overview of the work done in Brazil related to the development of instrumentation for measurements of the Cosmic Microwave Background and its contaminants. The microwave components and systems developed over the past two decades encompass waveguides, corrugated horns, transitions, ortho-mode transducers, receivers, and optical system. Partial to complete designs, simulations, and fabrication of these systems were conducted in order to build radiotelescopes that operated on the ground and on board stratospheric balloons to produce maps of the microwave emission of the sky between 1.465 GHz and 100 GHz.
{"title":"Microwave instrumentation for astrophysical observations: Some contributions","authors":"T. Villela","doi":"10.1109/MWSYM.2011.5972899","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972899","url":null,"abstract":"In this paper, it is presented a brief overview of the work done in Brazil related to the development of instrumentation for measurements of the Cosmic Microwave Background and its contaminants. The microwave components and systems developed over the past two decades encompass waveguides, corrugated horns, transitions, ortho-mode transducers, receivers, and optical system. Partial to complete designs, simulations, and fabrication of these systems were conducted in order to build radiotelescopes that operated on the ground and on board stratospheric balloons to produce maps of the microwave emission of the sky between 1.465 GHz and 100 GHz.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125007501","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972877
Bo Li, T. Salter, Yiming Zhai, Bo Yang, X. Shao, G. Metze, N. Goldsman
Wireless sensor networks(WSN) demand low power and low cost transceiver design. In this paper, an integrated transceiver system has been designed and fabricated using a 0.13µm CMOS process for ultra low power WSN applications. The system integrates an OOK receiver, a transmitter, RF/DC switches and a voltage regulator which provides comprehensive on-chip biasing circuitry in a 2×2mm2 chip. A common source low noise amplifier (LNA) works at sub-threshold range to achieve maximum power efficiency. A Villard voltage doubler circuit and a voltage transformer have been used to significantly improve the OOK signal demodulation efficiency and the system sensitivity with near zero power consumption. The system obtains a receiver sensitivity of −60 dBm with 4mW@1.4V.
无线传感器网络(WSN)要求低功耗、低成本的收发器设计。本文采用0.13 μ m CMOS工艺设计并制作了一个集成收发器系统，用于超低功耗WSN应用。该系统集成了OOK接收器、发射器、RF/DC开关和电压调节器，在2×2mm2芯片中提供了全面的片上偏置电路。普通源低噪声放大器(LNA)工作在亚阈值范围，以实现最大的功率效率。采用维拉德倍压电路和电压互感器，在接近零功耗的情况下显著提高了OOK信号解调效率和系统灵敏度。系统通过4mW@1.4V得到了−60dbm的接收机灵敏度。
{"title":"An integrated low power transceiver system","authors":"Bo Li, T. Salter, Yiming Zhai, Bo Yang, X. Shao, G. Metze, N. Goldsman","doi":"10.1109/MWSYM.2011.5972877","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972877","url":null,"abstract":"Wireless sensor networks(WSN) demand low power and low cost transceiver design. In this paper, an integrated transceiver system has been designed and fabricated using a 0.13µm CMOS process for ultra low power WSN applications. The system integrates an OOK receiver, a transmitter, RF/DC switches and a voltage regulator which provides comprehensive on-chip biasing circuitry in a 2×2mm2 chip. A common source low noise amplifier (LNA) works at sub-threshold range to achieve maximum power efficiency. A Villard voltage doubler circuit and a voltage transformer have been used to significantly improve the OOK signal demodulation efficiency and the system sensitivity with near zero power consumption. The system obtains a receiver sensitivity of −60 dBm with 4mW@1.4V.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125271462","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972898
C. Jung, B. Thomas, C. Lee, A. Peralta, J. Gill, K. Cooper, G. Chattopadhyay, E. Schlecht, R. Lin, I. Mehdi
Advanced semiconductor nanofabrication techniques are utilized to design, fabricate and demonstrate a super-compact, low-mass (<10 grams) submillimeter-wave heterodyne front-end. RF elements such as waveguides and channels are fabricated in a silicon wafer substrate using deep-reactive ion etching (DRIE). Etched patterns with sidewalls angles controlled with 1° precision are reported, while maintaining a surface roughness of better than 20 nm rms for the etched structures. This approach is being developed to build compact 2-D imaging arrays in the THz frequency range.
{"title":"Compact submillimeter-wave receivers made with semiconductor nano-fabrication technologies","authors":"C. Jung, B. Thomas, C. Lee, A. Peralta, J. Gill, K. Cooper, G. Chattopadhyay, E. Schlecht, R. Lin, I. Mehdi","doi":"10.1109/MWSYM.2011.5972898","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972898","url":null,"abstract":"Advanced semiconductor nanofabrication techniques are utilized to design, fabricate and demonstrate a super-compact, low-mass (<10 grams) submillimeter-wave heterodyne front-end. RF elements such as waveguides and channels are fabricated in a silicon wafer substrate using deep-reactive ion etching (DRIE). Etched patterns with sidewalls angles controlled with 1° precision are reported, while maintaining a surface roughness of better than 20 nm rms for the etched structures. This approach is being developed to build compact 2-D imaging arrays in the THz frequency range.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125210123","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972666
O. Civi, S. Demir, T. Akin
A review of the on-going research in Turkey, -in Middle East Technical University (METU)-, on tunable microwave components and reconfigurable antennas produced by RF MEMS technology is presented in this paper. As a key element of reconfigurable structures, several capacitive contact shunt RF MEMS switches are designed, fabricated and measured. Lifetime measurements show that these switches can operate more than 3.2 billion cycles with a bipolar actuation without any degradation in performance. Design and measurement results of some RF MEMS components fabricated in microelectronics fabrication facilities of METU such as switches, DMTL phase shifters, tunable impedance matching circuits, frequency tunable antennas, electronically scanning arrays and reflectarrays are presented focusing on the latest results.
{"title":"Reconfigurable antennas using RF-MEMS research in Turkey","authors":"O. Civi, S. Demir, T. Akin","doi":"10.1109/MWSYM.2011.5972666","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972666","url":null,"abstract":"A review of the on-going research in Turkey, -in Middle East Technical University (METU)-, on tunable microwave components and reconfigurable antennas produced by RF MEMS technology is presented in this paper. As a key element of reconfigurable structures, several capacitive contact shunt RF MEMS switches are designed, fabricated and measured. Lifetime measurements show that these switches can operate more than 3.2 billion cycles with a bipolar actuation without any degradation in performance. Design and measurement results of some RF MEMS components fabricated in microelectronics fabrication facilities of METU such as switches, DMTL phase shifters, tunable impedance matching circuits, frequency tunable antennas, electronically scanning arrays and reflectarrays are presented focusing on the latest results.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":" 21","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113948978","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 : 2011-06-05DOI: 10.1109/MWSYM.2011.5972657
D. Kang, Dongsu Kim, Yunsung Cho, Jooseung Kim, Byungjoon Park, Chenxi Zhao, Bumman Kim
A Doherty power amplifier (PA) for long term evolution (LTE) applications is fully integrated on a 1.4×1.4 mm2 die using a 2-µm InGaP/GaAs hetero-junction bipolar transistor (HBT) process. The quarter-wavelength transformer is the bandwidth (BW) limit of the Doherty PA. Other bandwidth limiting factors are analyzed and eliminated. A conventional phase compensation circuit and an additional offset line are merged into the input network of the Doherty PA and the output circuit of the peaking amplifier, respectively. The multi-section output matching having the same impedance transformation and a broadband input matching are utilized. A Wilkinson power divider is transformed into a lumped type and integrated on a chip for enhancing the bandwidth of Doherty operation. For a LTE signal with a 7.5-dB peak-to-average power ratio (PAPR) and a 10-MHz BW, the PA with a supply voltage of 4.5 V delivers a power-added efficiency (PAE) of 36.3%, and an adjacent channel leakage ratio (ACLR) of −32 dBc with an average output power of 27.5 dBm at a frequency of 1.85 GHz. Across 1.6–2.1 GHz, the PA performs a PAE of over 30%, a gain of over 28 dB and an ACLR of below −31 dBc at an average output power of 27.5 dBm while satisfying the standard spectrum mask. These results verify that the proposed bandwidth enhancement techniques are effective for the handset Doherty PA.
{"title":"1.6–2.1 GHz broadband Doherty power amplifiers for LTE handset applications","authors":"D. Kang, Dongsu Kim, Yunsung Cho, Jooseung Kim, Byungjoon Park, Chenxi Zhao, Bumman Kim","doi":"10.1109/MWSYM.2011.5972657","DOIUrl":"https://doi.org/10.1109/MWSYM.2011.5972657","url":null,"abstract":"A Doherty power amplifier (PA) for long term evolution (LTE) applications is fully integrated on a 1.4×1.4 mm2 die using a 2-µm InGaP/GaAs hetero-junction bipolar transistor (HBT) process. The quarter-wavelength transformer is the bandwidth (BW) limit of the Doherty PA. Other bandwidth limiting factors are analyzed and eliminated. A conventional phase compensation circuit and an additional offset line are merged into the input network of the Doherty PA and the output circuit of the peaking amplifier, respectively. The multi-section output matching having the same impedance transformation and a broadband input matching are utilized. A Wilkinson power divider is transformed into a lumped type and integrated on a chip for enhancing the bandwidth of Doherty operation. For a LTE signal with a 7.5-dB peak-to-average power ratio (PAPR) and a 10-MHz BW, the PA with a supply voltage of 4.5 V delivers a power-added efficiency (PAE) of 36.3%, and an adjacent channel leakage ratio (ACLR) of −32 dBc with an average output power of 27.5 dBm at a frequency of 1.85 GHz. Across 1.6–2.1 GHz, the PA performs a PAE of over 30%, a gain of over 28 dB and an ACLR of below −31 dBc at an average output power of 27.5 dBm while satisfying the standard spectrum mask. These results verify that the proposed bandwidth enhancement techniques are effective for the handset Doherty PA.","PeriodicalId":294862,"journal":{"name":"2011 IEEE MTT-S International Microwave Symposium","volume":"123 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114009816","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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