Pub Date : 2008-10-01DOI: 10.1109/EMICC.2008.4772307
T. Thrivikraman, W. Kuo, J. Comeau, J. Cressler
This work presents a comparison of three single-pole double-throw (SPDT) nMOS RF switches implemented in commercially available Si-based 180, 130, and 90 nm technologies. In addition, a new series-shunt switch is presented that offers a means to improve switch isolation. Measured results of these RF switches demonstrates how technology node scaling impacts RF switch design and provides insight into the complicated trade-offs between insertion loss, isolation, and linearity.
{"title":"The Impact of Technology Node Scaling on nMOS SPDT RF Switches","authors":"T. Thrivikraman, W. Kuo, J. Comeau, J. Cressler","doi":"10.1109/EMICC.2008.4772307","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772307","url":null,"abstract":"This work presents a comparison of three single-pole double-throw (SPDT) nMOS RF switches implemented in commercially available Si-based 180, 130, and 90 nm technologies. In addition, a new series-shunt switch is presented that offers a means to improve switch isolation. Measured results of these RF switches demonstrates how technology node scaling impacts RF switch design and provides insight into the complicated trade-offs between insertion loss, isolation, and linearity.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134456956","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772355
C. Costrini, M. Calori, A. Cetronio, C. Lanzieri, S. Lavanga, M. Peroni, E. Limiti, A. Serino, G. Ghione, G. Melone
In this paper a first iteration design, fabrication and test of a two-stage X-Band MMIC HPA in micro-strip AlGaN/GaN technology is reported. With 20 V drain voltage operating bias point, at 3 dB compression point, the HPA delivers a pulsed output power ranging from 21 to 28.5 W, an associated gain from 12.9 to 16.5 dB and an associated PAE from circa 30% to 40%, over the 8-10.5 GHz frequency bandwidth. In the best performance frequency points (8.5 and 9 GHz) the HPA exhibits a saturated output power of 30 W with an associated PAE of 40%.
{"title":"A 20 Watt Micro-strip X-Band AlGaN/GaN HPA MMIC for Advanced Radar Applications","authors":"C. Costrini, M. Calori, A. Cetronio, C. Lanzieri, S. Lavanga, M. Peroni, E. Limiti, A. Serino, G. Ghione, G. Melone","doi":"10.1109/EMICC.2008.4772355","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772355","url":null,"abstract":"In this paper a first iteration design, fabrication and test of a two-stage X-Band MMIC HPA in micro-strip AlGaN/GaN technology is reported. With 20 V drain voltage operating bias point, at 3 dB compression point, the HPA delivers a pulsed output power ranging from 21 to 28.5 W, an associated gain from 12.9 to 16.5 dB and an associated PAE from circa 30% to 40%, over the 8-10.5 GHz frequency bandwidth. In the best performance frequency points (8.5 and 9 GHz) the HPA exhibits a saturated output power of 30 W with an associated PAE of 40%.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129366514","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772213
M. Peter, W. Keusgen, Jian Luo
This paper gives a review of important aspects and current developments in 60 GHz broadband communication. We present channel measurement results for a conference room and analyze the channel capacity. The results clearly demonstrate the capability of the 60 GHz approach. Finally, we outline a concept for a wireless 60 GHz in-flight entertainment system.
{"title":"A Survey on 60 GHz Broadband Communication: Capability, Applications and System Design","authors":"M. Peter, W. Keusgen, Jian Luo","doi":"10.1109/EMICC.2008.4772213","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772213","url":null,"abstract":"This paper gives a review of important aspects and current developments in 60 GHz broadband communication. We present channel measurement results for a conference room and analyze the channel capacity. The results clearly demonstrate the capability of the 60 GHz approach. Finally, we outline a concept for a wireless 60 GHz in-flight entertainment system.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116570294","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772267
D. Smith, G. Dambrine, J. Orlhac
This paper describes the industrial development methodology of a family of MHEMT technologies with gate lengths from 130 down to 50 nm. State of the art MMIC LNA performance for the commercial 70 nm technology at 90 and 150 GHz is presented.
{"title":"Industrial MHEMT Technologies for 80 - 220 GHz Applications","authors":"D. Smith, G. Dambrine, J. Orlhac","doi":"10.1109/EMICC.2008.4772267","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772267","url":null,"abstract":"This paper describes the industrial development methodology of a family of MHEMT technologies with gate lengths from 130 down to 50 nm. State of the art MMIC LNA performance for the commercial 70 nm technology at 90 and 150 GHz is presented.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125922175","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772256
Senhg-Feng Lu, Jyh-Chyurn Guo
A CMOS mixer was design with a new circuit scheme to realize low voltage and high linearity simultaneously. A double balanced Gilbert cell was adopted as the basic topology and TSMC 0.18 mum 1P6M CMOS process was employed for the on-chip RF circuit fabrication. The proposed new circuit scheme consists of LC-tanks as a capacitively coupled resonator for low voltage and multi-stage parallel RC networks for linearity improvement. Furthermore, multi-gated structure is applied at the RF input as a transconductance amplifier to enhance conversion gain and linearity. The new circuit scheme enables a successful low voltage operation at 1-V for 0.18 mum technology, The measured circuit performance demonstrates superior linearity with IIP3 of 11 dBm and P1dB of 2.2 dBm. The conversion gain can be maintained at 8.1 dB in a wide frequencies of 5 GHz to 6.8 GHz.
{"title":"5.5 GHz Low Voltage and High Linearity RF CMOS Mixer Design","authors":"Senhg-Feng Lu, Jyh-Chyurn Guo","doi":"10.1109/EMICC.2008.4772256","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772256","url":null,"abstract":"A CMOS mixer was design with a new circuit scheme to realize low voltage and high linearity simultaneously. A double balanced Gilbert cell was adopted as the basic topology and TSMC 0.18 mum 1P6M CMOS process was employed for the on-chip RF circuit fabrication. The proposed new circuit scheme consists of LC-tanks as a capacitively coupled resonator for low voltage and multi-stage parallel RC networks for linearity improvement. Furthermore, multi-gated structure is applied at the RF input as a transconductance amplifier to enhance conversion gain and linearity. The new circuit scheme enables a successful low voltage operation at 1-V for 0.18 mum technology, The measured circuit performance demonstrates superior linearity with IIP3 of 11 dBm and P1dB of 2.2 dBm. The conversion gain can be maintained at 8.1 dB in a wide frequencies of 5 GHz to 6.8 GHz.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129105509","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772246
A. Rodríguez-Testera, O. Mojón, M. Fernández-Barciela, E. Sánchez
A table-based nonlinear approach was used to predict the performance of a commercially packaged Schottky diode. Excellent results have been obtained which improve those of the analytical model provided by the manufacturer. Both models were extensively validated under DC, small and large-signal one-tone and two-tone excitations. Measurements for table-based model extraction and models validation were obtained by using a multi-tone nonlinear measurement system based on a LSNA. Time domain waveforms have once more been demonstrated as a key tool to compare large-signal models.
{"title":"Robust Packaged Diode Modelling with a Table-Based Approach","authors":"A. Rodríguez-Testera, O. Mojón, M. Fernández-Barciela, E. Sánchez","doi":"10.1109/EMICC.2008.4772246","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772246","url":null,"abstract":"A table-based nonlinear approach was used to predict the performance of a commercially packaged Schottky diode. Excellent results have been obtained which improve those of the analytical model provided by the manufacturer. Both models were extensively validated under DC, small and large-signal one-tone and two-tone excitations. Measurements for table-based model extraction and models validation were obtained by using a multi-tone nonlinear measurement system based on a LSNA. Time domain waveforms have once more been demonstrated as a key tool to compare large-signal models.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123155585","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772258
J. Cumana, C. Lautensack, M. Eickelkamp, J. Goliasch, A. Noculak, A. Vescan, R. Jansen
GaN HFETs and MISHFETs are promising power devices for RF and microwave power applications. However, the performance of devices can be compromised under some operating conditions. From the device development point of view, device optimization is necessary to obtain the best possible performance. For device modeling and design purposes, the device needs to be characterized and modeled accurately in order to foresee how the device will behave under realistic operating conditions. In this paper, an improved EEHEMT1-based model for GaN MISHFETs, will be introduced. This model is capable of describing the knee region of the device's output characteristics, dispersion effects as well as gate diode behavior accurately. The models will be incorporated in a switched-mode amplifier topology and evaluations will be made to determine the suitability of MISHFETs in these amplifiers.
GaN hfet和mishfet是射频和微波功率应用中很有前途的功率器件。但是，在某些操作条件下，设备的性能可能会受到影响。从器件开发的角度来看，器件优化是获得最佳性能的必要条件。为了设备建模和设计的目的，需要对设备进行准确的表征和建模，以便预见设备在实际操作条件下的行为。本文将介绍一种改进的基于eehemt1的GaN mishfet模型。该模型能够准确地描述器件输出特性、色散效应以及栅极二极管行为的膝区。这些模型将被整合到一个开关模式放大器拓扑结构中，并将进行评估，以确定mishfet在这些放大器中的适用性。
{"title":"Advanced Modeling of MISHFET Devices and their Performance in Current-Mode Class-D Power Amplifiers","authors":"J. Cumana, C. Lautensack, M. Eickelkamp, J. Goliasch, A. Noculak, A. Vescan, R. Jansen","doi":"10.1109/EMICC.2008.4772258","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772258","url":null,"abstract":"GaN HFETs and MISHFETs are promising power devices for RF and microwave power applications. However, the performance of devices can be compromised under some operating conditions. From the device development point of view, device optimization is necessary to obtain the best possible performance. For device modeling and design purposes, the device needs to be characterized and modeled accurately in order to foresee how the device will behave under realistic operating conditions. In this paper, an improved EEHEMT1-based model for GaN MISHFETs, will be introduced. This model is capable of describing the knee region of the device's output characteristics, dispersion effects as well as gate diode behavior accurately. The models will be incorporated in a switched-mode amplifier topology and evaluations will be made to determine the suitability of MISHFETs in these amplifiers.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131401927","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772316
Sang-Heung Lee, Ja-yol Lee, Hae-cheon Kim
In this paper, a 60 GHz MMIC down-conversion mixer for 60 GHz WPAN is designed and fabricated on chip using 0.25 mum SiGe:C BiCMOS process technology. This 60 GHz mixer is fully integrated on chip, including active input balun and output balun circuits. The results of the fabricated mixer measured at RF 60 GHz show conversion gain of 10.7 dB, LO to IF isolation and RF to IF isolation of above 30 dB, and input P1dB of -17 dBm. Also, the results of the fabricated mixer measured between RF 57 and 63 GHz show conversion gain of 12.0 ~ 10.7 dB, LO to IF isolation and RF to IF isolation of above 28 dB, and input P1dB of -17 ~ -18 dBm. The chip size of the manufactured mixer is 1.3 mm times 0.8 mm.
{"title":"A Fully Integrated 60 GHz SiGe BiCMOS Mixer","authors":"Sang-Heung Lee, Ja-yol Lee, Hae-cheon Kim","doi":"10.1109/EMICC.2008.4772316","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772316","url":null,"abstract":"In this paper, a 60 GHz MMIC down-conversion mixer for 60 GHz WPAN is designed and fabricated on chip using 0.25 mum SiGe:C BiCMOS process technology. This 60 GHz mixer is fully integrated on chip, including active input balun and output balun circuits. The results of the fabricated mixer measured at RF 60 GHz show conversion gain of 10.7 dB, LO to IF isolation and RF to IF isolation of above 30 dB, and input P1dB of -17 dBm. Also, the results of the fabricated mixer measured between RF 57 and 63 GHz show conversion gain of 12.0 ~ 10.7 dB, LO to IF isolation and RF to IF isolation of above 28 dB, and input P1dB of -17 ~ -18 dBm. The chip size of the manufactured mixer is 1.3 mm times 0.8 mm.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127224725","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772327
V. Napijalo, V. Cojocaru
An I/Q active mixer in LTCC technology using packaged HEMTs as mixing devices is described. A mixer is designed for use in the 24 GHz automotive radar application. An on-tile buffer amplifier was added to compensate for the limited power available from the system oscillator. Careful choice of the type or topology for each of the passive circuits implemented resulted in an optimal mixer layout, so a very small size for a ceramic tile of 15times15times0.8 mm3 was achieved. The measured conversion gain of the mixer for a 0 dBm LO level was -6.7 dB for I and -5.2 dB for Q. The amplitude imbalance between I and Q signals resulting from the aggressive miniaturization of the quadrature coupler could be compensated in the DSP stages of the system at no additional cost. The measured I-Q phase imbalance was around 3 degrees. The measured return losses at mixer ports and LO-RF isolations are also very good.
介绍了一种采用封装hemt作为混合器件的LTCC技术中的I/Q有源混频器。混频器设计用于24 GHz汽车雷达应用。增加了一个片上缓冲放大器来补偿系统振荡器提供的有限功率。为实现的每个无源电路精心选择类型或拓扑结构，从而实现最佳混频器布局，因此实现了瓷砖的15 × 15 × 0.8 mm3的非常小的尺寸。对于0 dBm的LO电平，混频器的测量转换增益为-6.7 dB (I)和-5.2 dB (Q)。由于正交耦合器的积极小型化而导致的I和Q信号之间的幅度不平衡可以在系统的DSP级中进行补偿，而无需额外成本。测得的I-Q相不平衡约为3度。在混频器端口和LO-RF隔离处测量的回波损耗也非常好。
{"title":"24 GHz LTCC I/Q Mixer Using Packaged HEMTs","authors":"V. Napijalo, V. Cojocaru","doi":"10.1109/EMICC.2008.4772327","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772327","url":null,"abstract":"An I/Q active mixer in LTCC technology using packaged HEMTs as mixing devices is described. A mixer is designed for use in the 24 GHz automotive radar application. An on-tile buffer amplifier was added to compensate for the limited power available from the system oscillator. Careful choice of the type or topology for each of the passive circuits implemented resulted in an optimal mixer layout, so a very small size for a ceramic tile of 15times15times0.8 mm3 was achieved. The measured conversion gain of the mixer for a 0 dBm LO level was -6.7 dB for I and -5.2 dB for Q. The amplitude imbalance between I and Q signals resulting from the aggressive miniaturization of the quadrature coupler could be compensated in the DSP stages of the system at no additional cost. The measured I-Q phase imbalance was around 3 degrees. The measured return losses at mixer ports and LO-RF isolations are also very good.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127006829","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 : 2008-10-01DOI: 10.1109/EMICC.2008.4772294
T. Wallin, J. Hellén, H. Berg, S.-E. Elfgren
Using traditional RFIC design architecture a broadband regenerative frequency divider is designed. By integrating the frequency divider in a single IC the size is reduced and the bandwidth is increased without compromising the phase noise performance. A one octave bandwidth, 3.2-6.4 GHz, is achieved with a phase noise floor below -157 dBc/Hz. For a narrower frequency band, 4.0-5.6 GHz, a phase noise floor below -167 dBc/Hz is measured. This is directly comparable to regenerative frequency dividers designed using conventional discrete components or commercially available dividers. At the same time the bandwidth is exceeded only by digital dividers, they however have a typical phase noise floor of -150 dBc/Hz at these frequencies. Both f0/2 and 3f0/2 are available at the output while the input frequency, f0, is suppressed to at least -20 dBc. The IC is manufactured by austriamicrosystems in their 0.35 mum SiGe-BiCMOS process with an fT of 70 GHz and is packaged in a 5times5 mm QFN plastic package.
{"title":"Regenerative Frequency Divider SiGe-RFIC with Octave Bandwidth and Low Phase Noise","authors":"T. Wallin, J. Hellén, H. Berg, S.-E. Elfgren","doi":"10.1109/EMICC.2008.4772294","DOIUrl":"https://doi.org/10.1109/EMICC.2008.4772294","url":null,"abstract":"Using traditional RFIC design architecture a broadband regenerative frequency divider is designed. By integrating the frequency divider in a single IC the size is reduced and the bandwidth is increased without compromising the phase noise performance. A one octave bandwidth, 3.2-6.4 GHz, is achieved with a phase noise floor below -157 dBc/Hz. For a narrower frequency band, 4.0-5.6 GHz, a phase noise floor below -167 dBc/Hz is measured. This is directly comparable to regenerative frequency dividers designed using conventional discrete components or commercially available dividers. At the same time the bandwidth is exceeded only by digital dividers, they however have a typical phase noise floor of -150 dBc/Hz at these frequencies. Both f0/2 and 3f0/2 are available at the output while the input frequency, f0, is suppressed to at least -20 dBc. The IC is manufactured by austriamicrosystems in their 0.35 mum SiGe-BiCMOS process with an fT of 70 GHz and is packaged in a 5times5 mm QFN plastic package.","PeriodicalId":344657,"journal":{"name":"2008 European Microwave Integrated Circuit Conference","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128171370","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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