Pub Date : 2015-08-01DOI: 10.1109/RFIT.2015.7377915
M. Motoyoshi, Mikoto Nakamura, S. Kameda, N. Suematsu, T. Takagi, K. Tsubouchi
Self-directed beamforming system is to calculate phase difference from signals received at each element of the array antennas with digital signal processing and estimate the direction of arrival of the signal, and form a main beam to the direction. When conventional self-directed beamforming method is applied to broadband communication, the processing of broadband signals as many as antenna elements is required, thus it is difficult to add the method to mobile terminals. We have proposed self-directed beamforming method easily applied to broadband communication. In this method beams were controlled with phase information extracted from low frequency component of received signal. In this paper, prior to verification at RF-band, IF receiver modules were fabricated and the correct operation of the proposed method was confirmed. BF experiment using 2Gbps QPSK signal assuming IEEE 802.15.3c was performed. As a result of synthesis of four IF modules, improvement of the SNR approximately proportional to the number of the synthesized modules was confirmed.
{"title":"Self-directed beamforming IF receiver for broadband communication using low frequency loop control","authors":"M. Motoyoshi, Mikoto Nakamura, S. Kameda, N. Suematsu, T. Takagi, K. Tsubouchi","doi":"10.1109/RFIT.2015.7377915","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377915","url":null,"abstract":"Self-directed beamforming system is to calculate phase difference from signals received at each element of the array antennas with digital signal processing and estimate the direction of arrival of the signal, and form a main beam to the direction. When conventional self-directed beamforming method is applied to broadband communication, the processing of broadband signals as many as antenna elements is required, thus it is difficult to add the method to mobile terminals. We have proposed self-directed beamforming method easily applied to broadband communication. In this method beams were controlled with phase information extracted from low frequency component of received signal. In this paper, prior to verification at RF-band, IF receiver modules were fabricated and the correct operation of the proposed method was confirmed. BF experiment using 2Gbps QPSK signal assuming IEEE 802.15.3c was performed. As a result of synthesis of four IF modules, improvement of the SNR approximately proportional to the number of the synthesized modules was confirmed.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116572311","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377927
M. van Delden, G. Hasenaecker, N. Pohl, K. Aufinger, T. Musch
A programmable frequency divider operating at input frequencies from DC to 80 GHz for the use in fractional-N synthesizers is presented. The division factor can be set to all integer values between 12 and 259 and is applied by an 8 bit parallel interface for fast modulation. The remarkably high input frequency in combination with the programmability is achieved by a dual-modulus concept and differential emitter-coupled logic with a consequent merging of logic gates into flip-flops. Among this, a reset function has been implemented to synchronize multiple synthesizers. The frequency divider has been realized in a SiGe BiCMOS technology (fr/fmax=250/360 GHz). The divider works at a supply voltage of 3.3 V with a power consumption of less than 390 mW.
{"title":"An 80 GHz programmable frequency divider for wideband mm-Wave frequency ramp synthesis","authors":"M. van Delden, G. Hasenaecker, N. Pohl, K. Aufinger, T. Musch","doi":"10.1109/RFIT.2015.7377927","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377927","url":null,"abstract":"A programmable frequency divider operating at input frequencies from DC to 80 GHz for the use in fractional-N synthesizers is presented. The division factor can be set to all integer values between 12 and 259 and is applied by an 8 bit parallel interface for fast modulation. The remarkably high input frequency in combination with the programmability is achieved by a dual-modulus concept and differential emitter-coupled logic with a consequent merging of logic gates into flip-flops. Among this, a reset function has been implemented to synchronize multiple synthesizers. The frequency divider has been realized in a SiGe BiCMOS technology (fr/fmax=250/360 GHz). The divider works at a supply voltage of 3.3 V with a power consumption of less than 390 mW.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122692545","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377896
Ryo Shimofusa, Y. Okano
The specific absorption rate (SAR) is an indicator of the thermal effects caused by microwave exposure in biological tissues. Electric field probe scanning has been used as a practical SAR evaluation technology until now. A measurement standard is necessary for any physical quantity. In general, the existence of a standard constructed with a physically different procedure is important in uncertainty evaluation of the measurement standard. In this report, a thermal SAR measurement method using an optical fiber thermal sensor is proposed. The thermal SAR measurement method is not suitable for dosimetric assessments for an actual cellular phone. Nevertheless, a thermal sensor works independently of the frequency, and is therefore suitable for primary testing of an electric field probe scanning system. The results show that the proposed method is able to measure SAR within an error range of 1-13% in frequency range of 300-800 MHz and 2-6 GHz.
{"title":"Broadband measurement system for the specific absorption rate above 300 MHz","authors":"Ryo Shimofusa, Y. Okano","doi":"10.1109/RFIT.2015.7377896","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377896","url":null,"abstract":"The specific absorption rate (SAR) is an indicator of the thermal effects caused by microwave exposure in biological tissues. Electric field probe scanning has been used as a practical SAR evaluation technology until now. A measurement standard is necessary for any physical quantity. In general, the existence of a standard constructed with a physically different procedure is important in uncertainty evaluation of the measurement standard. In this report, a thermal SAR measurement method using an optical fiber thermal sensor is proposed. The thermal SAR measurement method is not suitable for dosimetric assessments for an actual cellular phone. Nevertheless, a thermal sensor works independently of the frequency, and is therefore suitable for primary testing of an electric field probe scanning system. The results show that the proposed method is able to measure SAR within an error range of 1-13% in frequency range of 300-800 MHz and 2-6 GHz.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131526284","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377922
I. Soga, Yohei Yagishita, H. Matsumura, Y. Kawano, Toshihide Suzuki, T. Iwai
This paper describes the implementation of 76-81 GHz power amplifier (PA) in 65 nm CMOS technology. A customized transistor model enables the designing circuits operating at mm-wave band. The output matching of the PA was composed of low-pass network to reduce both footprint and matching loss. This makes the PA ideal for phased array radars. The measured results at 79 GHz achieved the small signal gain of 25.1 dB, the saturated output power (Psat) of 11.5 dBm, and the power added efficiency (PAE) of 13.6% at the supply voltage of 0.8 V. These results agreed with the simulation.
{"title":"A 76–81 GHz high efficiency power amplifier for phased array automotive radar applications","authors":"I. Soga, Yohei Yagishita, H. Matsumura, Y. Kawano, Toshihide Suzuki, T. Iwai","doi":"10.1109/RFIT.2015.7377922","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377922","url":null,"abstract":"This paper describes the implementation of 76-81 GHz power amplifier (PA) in 65 nm CMOS technology. A customized transistor model enables the designing circuits operating at mm-wave band. The output matching of the PA was composed of low-pass network to reduce both footprint and matching loss. This makes the PA ideal for phased array radars. The measured results at 79 GHz achieved the small signal gain of 25.1 dB, the saturated output power (Psat) of 11.5 dBm, and the power added efficiency (PAE) of 13.6% at the supply voltage of 0.8 V. These results agreed with the simulation.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114600216","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377924
K. Ohhata
In this paper, the latest research results of high-speed, low-power subranging ADC technologies are presented. The offset cancelling charge steering amplifier realizes a low-power and high-precision comparator, resulting in a low-power subranging ADC without digital calibration. Moreover, the built-in threshold calibration combining offset drift compensation enables an extremely low-power subranging ADC that is equally matched for SAR ADCs.
{"title":"High-speed, low-power subranging ADCs","authors":"K. Ohhata","doi":"10.1109/RFIT.2015.7377924","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377924","url":null,"abstract":"In this paper, the latest research results of high-speed, low-power subranging ADC technologies are presented. The offset cancelling charge steering amplifier realizes a low-power and high-precision comparator, resulting in a low-power subranging ADC without digital calibration. Moreover, the built-in threshold calibration combining offset drift compensation enables an extremely low-power subranging ADC that is equally matched for SAR ADCs.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124753914","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377948
Y. Itoh, Hirohito Mizuo, A. Ohta
A dual-band SiGe HBT active load is presented for use in the reflection type phase shifter with a wide phase-shifting range and low insertion losses. The active load is based on a common-emitter configuration of SiGe HBTs employing stacked LC resonators in the load circuit for a wide shifting-range at multiple frequencies as well as RC series feedback circuits between emitter and ground for improving return losses. Since the parallel LC resonators with different resonant frequencies are stacked in configuration, the individual resonant frequency can be varied independently. The implemented dual-band active load using 0.35 μm SiGe HBTs with an ft of 25 GHz and Si varactor diodes with a capacitance ratio of 2.5:1 has achieved a maximal phase shift and a return loss of 270° and 0.6 dB at 0.64 GHz as well as 300o and 1.9 dB at 0.87 GHz, respectively.
{"title":"A dual-band SiGe HBT active load using stacked LC resonators and RC series feedback circuits","authors":"Y. Itoh, Hirohito Mizuo, A. Ohta","doi":"10.1109/RFIT.2015.7377948","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377948","url":null,"abstract":"A dual-band SiGe HBT active load is presented for use in the reflection type phase shifter with a wide phase-shifting range and low insertion losses. The active load is based on a common-emitter configuration of SiGe HBTs employing stacked LC resonators in the load circuit for a wide shifting-range at multiple frequencies as well as RC series feedback circuits between emitter and ground for improving return losses. Since the parallel LC resonators with different resonant frequencies are stacked in configuration, the individual resonant frequency can be varied independently. The implemented dual-band active load using 0.35 μm SiGe HBTs with an ft of 25 GHz and Si varactor diodes with a capacitance ratio of 2.5:1 has achieved a maximal phase shift and a return loss of 270° and 0.6 dB at 0.64 GHz as well as 300o and 1.9 dB at 0.87 GHz, respectively.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125075985","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377867
S. Masui, K. Kanda, K. Oishi, K. Philips, H. de Groot
An energy-efficient radio SoC with RF front-end, DBB (digital baseband) and MCU (microcontroller) for medical/healthcare applications in 315/400 MHz bands is presented. The SoC is fully-compliant with IEEE 802.15.6 standard in 402-405MHz MICS (Medical Implant Communication Service) band and 420-450MHz ISM (Industrial, Scientific, and Medical) band, and also supports a proprietary mode with a high data rate up to 3.6Mb/s to support applications such as EEG streaming. The ADPLL (all-digital phase-locked loop)-based transmitter is adopted to support various modulation schemes with limited power budget. Fabricated in 40nm CMOS technology with 1V supply, the transceiver SoC with DBB and MAC MCU has total power consumption of 3.5mW (RX, 3.6Mb/s, -77dBm sensitivity) and 3.0mW (TX, 3.6Mb/s, -16dBm PA output) enabling best-in-class power efficiency less than 1nJ/bit.
{"title":"An ultra-low-power wireless transceiver SoC for medical applications","authors":"S. Masui, K. Kanda, K. Oishi, K. Philips, H. de Groot","doi":"10.1109/RFIT.2015.7377867","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377867","url":null,"abstract":"An energy-efficient radio SoC with RF front-end, DBB (digital baseband) and MCU (microcontroller) for medical/healthcare applications in 315/400 MHz bands is presented. The SoC is fully-compliant with IEEE 802.15.6 standard in 402-405MHz MICS (Medical Implant Communication Service) band and 420-450MHz ISM (Industrial, Scientific, and Medical) band, and also supports a proprietary mode with a high data rate up to 3.6Mb/s to support applications such as EEG streaming. The ADPLL (all-digital phase-locked loop)-based transmitter is adopted to support various modulation schemes with limited power budget. Fabricated in 40nm CMOS technology with 1V supply, the transceiver SoC with DBB and MAC MCU has total power consumption of 3.5mW (RX, 3.6Mb/s, -77dBm sensitivity) and 3.0mW (TX, 3.6Mb/s, -16dBm PA output) enabling best-in-class power efficiency less than 1nJ/bit.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121895670","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377893
Yunshan Wang, Chau-Ching Chiong, Ji-Kang Nai, Huei Wang
A broadband, high gain low noise amplifier (LNA) for radio astronomy application is developed. This work is implemented using 0.15-μm GaAs pseudomorphic high electron mobility transistor (pHEMT) process. An inductive feedback gain compensation topology is applied for broadband design. This LNA shows small signal gain 34.3 dB from 3.2 to 14.7 GHz with 0.8-dB gain variation from 4.6 to 13.8 GHz and a dc consumption 45 mW. It demonstrates a measured noise figure between 1.3 and 1.6 dB from 4.6 to 13.8 GHz.
{"title":"A high gain broadband LNA in GaAs 0.15-μm pHEMT process using inductive feedback gain compensation for radio astronomy applications","authors":"Yunshan Wang, Chau-Ching Chiong, Ji-Kang Nai, Huei Wang","doi":"10.1109/RFIT.2015.7377893","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377893","url":null,"abstract":"A broadband, high gain low noise amplifier (LNA) for radio astronomy application is developed. This work is implemented using 0.15-μm GaAs pseudomorphic high electron mobility transistor (pHEMT) process. An inductive feedback gain compensation topology is applied for broadband design. This LNA shows small signal gain 34.3 dB from 3.2 to 14.7 GHz with 0.8-dB gain variation from 4.6 to 13.8 GHz and a dc consumption 45 mW. It demonstrates a measured noise figure between 1.3 and 1.6 dB from 4.6 to 13.8 GHz.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127599972","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377888
D. Kholodnyak, E. Zameshaeva, V. Turgaliev, E. Vorobev
Tunability analysis is presented for dual-frequency immittance inverters based on the dual-composite right/left-handed transmission line (D-CRLH TL) unit cells with variable capacitors. The inverter tunability is limited by a tolerable variation of the inverter parameter. At least ±10% tuning of the both inverter operational frequencies is shown feasible.
{"title":"Tunability of dual-frequency immittance inverters on dual-composite right/left-handed transmission lines (D-CRLH TL) with variable capacitors","authors":"D. Kholodnyak, E. Zameshaeva, V. Turgaliev, E. Vorobev","doi":"10.1109/RFIT.2015.7377888","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377888","url":null,"abstract":"Tunability analysis is presented for dual-frequency immittance inverters based on the dual-composite right/left-handed transmission line (D-CRLH TL) unit cells with variable capacitors. The inverter tunability is limited by a tolerable variation of the inverter parameter. At least ±10% tuning of the both inverter operational frequencies is shown feasible.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128358008","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 : 2015-08-01DOI: 10.1109/RFIT.2015.7377884
Ho-Jin Song, T. Tajima, T. Kosugi, H. Hamada, A. El Moutaouakil, H. Sugiyama, H. Matsuzaki, M. Yaita, S. Kodama, O. Kagami
In this report, we briefly presented the concept of the KIOSK data downloading system at 300-GHz and MMICs for the transmitter based on the state-of-art InP HEMTs technology. Recently, we have achieved the 20-Gbps error free data transmission (BER <; 10 -9) over 1-meter distance with the MMICs in well controlled experimental environment. Those results will be presented in future. In addition, concept and consideration for the small package for receiver modules was presented. Based on the standard LTCC technologies, we experimentally demonstrated the broadband high gain antenna with the volume less than 0.1 cc. This work was supported in part by the research and development program on Multi-tens gigabit wireless communication technology at sub-terahertz frequencies of the Ministry of Internal Affairs and Communications, Japan.
{"title":"Demonstration of KIOSK data downloading system at 300 GHz based on InP MMICs","authors":"Ho-Jin Song, T. Tajima, T. Kosugi, H. Hamada, A. El Moutaouakil, H. Sugiyama, H. Matsuzaki, M. Yaita, S. Kodama, O. Kagami","doi":"10.1109/RFIT.2015.7377884","DOIUrl":"https://doi.org/10.1109/RFIT.2015.7377884","url":null,"abstract":"In this report, we briefly presented the concept of the KIOSK data downloading system at 300-GHz and MMICs for the transmitter based on the state-of-art InP HEMTs technology. Recently, we have achieved the 20-Gbps error free data transmission (BER <; 10 -9) over 1-meter distance with the MMICs in well controlled experimental environment. Those results will be presented in future. In addition, concept and consideration for the small package for receiver modules was presented. Based on the standard LTCC technologies, we experimentally demonstrated the broadband high gain antenna with the volume less than 0.1 cc. This work was supported in part by the research and development program on Multi-tens gigabit wireless communication technology at sub-terahertz frequencies of the Ministry of Internal Affairs and Communications, Japan.","PeriodicalId":422369,"journal":{"name":"2015 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122864071","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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