An ultra-wideband balanced bandpass filter (BPF) by using multilayer liquid crystal polymer (LCP) circuit technology with self-packaging feature is presented in this paper. The differential-mode (DM) half circuit of the proposed filter is provided and analyzed, showing that the balanced filter exhibits a four-pole ultra-wideband Chebyshev filtering response. In addition, the common-mode (CM) signals can be suppressed in a wide bandwidth region owing to the all-stop coupled-line topology in the CM equivalent circuit. Finally, an LCP balanced BPF with ultra-wideband Chebyshev response is designed, fabricated and measured. Simulated and measured results are recorded in good agreement, well validating the design method.
{"title":"Self-Packaged Ultra-Wideband Balanced Bandpass Filter Using Multilayer Liquid Crystal Polymer Circuit Technology","authors":"Feng Huang, Khaled Aliqab, Jianpeng Wang, Jiasheng Hong, Wen Wu","doi":"10.1109/IEEE-IWS.2019.8803897","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803897","url":null,"abstract":"An ultra-wideband balanced bandpass filter (BPF) by using multilayer liquid crystal polymer (LCP) circuit technology with self-packaging feature is presented in this paper. The differential-mode (DM) half circuit of the proposed filter is provided and analyzed, showing that the balanced filter exhibits a four-pole ultra-wideband Chebyshev filtering response. In addition, the common-mode (CM) signals can be suppressed in a wide bandwidth region owing to the all-stop coupled-line topology in the CM equivalent circuit. Finally, an LCP balanced BPF with ultra-wideband Chebyshev response is designed, fabricated and measured. Simulated and measured results are recorded in good agreement, well validating the design method.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116548802","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 : 2019-08-19DOI: 10.1109/IEEE-IWS.2019.8803929
Abdoalbaset Abohmra, Fizzah Jilani, H. Abbas, M. Imran, Q. Abbasi
This paper presents the potential of a graphene antenna in the terahertz band for flexible and wearable telecommunication applications. Graphene with its extraordinary electronic properties can be used to fabricate low-profile antennas that provide wearability. Here we investigate the possible resonant frequencies of graphene antenna in the terahertz band by varying the graphene chemical potential from 0.1 eV to 0.4 eV and the relaxation time from 0.1 ps to 0.8 ps. We show that the antenna can resonate at three different frequencies of 4.546 THz, 4.636THz and 5.347 THz. An improved bandwidth at higher chemical potential 0.4 eV observed at 5.5 THz but it is accompanied by a lower directivity compared with the other two resonant frequencies. Moreover, we evaluated the effect of the substrate thickness on surface plasmon polarities (SPPs). Such flexible antennas with a large bandwidth and tunability point to a bright future of terahertz frequency wearable applications.
{"title":"Terahertz Antenna based on Graphene for Wearable Applications","authors":"Abdoalbaset Abohmra, Fizzah Jilani, H. Abbas, M. Imran, Q. Abbasi","doi":"10.1109/IEEE-IWS.2019.8803929","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803929","url":null,"abstract":"This paper presents the potential of a graphene antenna in the terahertz band for flexible and wearable telecommunication applications. Graphene with its extraordinary electronic properties can be used to fabricate low-profile antennas that provide wearability. Here we investigate the possible resonant frequencies of graphene antenna in the terahertz band by varying the graphene chemical potential from 0.1 eV to 0.4 eV and the relaxation time from 0.1 ps to 0.8 ps. We show that the antenna can resonate at three different frequencies of 4.546 THz, 4.636THz and 5.347 THz. An improved bandwidth at higher chemical potential 0.4 eV observed at 5.5 THz but it is accompanied by a lower directivity compared with the other two resonant frequencies. Moreover, we evaluated the effect of the substrate thickness on surface plasmon polarities (SPPs). Such flexible antennas with a large bandwidth and tunability point to a bright future of terahertz frequency wearable applications.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127567333","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 : 2019-08-19DOI: 10.1109/IEEE-IWS.2019.8803875
A. Valavanis, O. Auriacombe, T. Rawlings, Y. Han, S. Rea, M. Crook, C. Arena, D. Walker, D. Brooks, G. Yu, L. Li, A. Davies, G. Savini, E. Linfield, B. Ellison, E. Sáenz
Terahertz-frequency quantum-cascade lasers (THz QCLs) are compact, electrically-driven sources of narrowband radiation in the ~2–5-THz band. Numerous scientifically important gas-phase species within the Earth’s upper atmosphere have distinctive spectral features within this band, making QCLs attractive sources for spectroscopic and radiometric atmospheric studies. In this paper, we demonstrate the integration of a QCL with a satellite-compliant cryocooler, precision-micromachined waveguide, a pair of diagonal feedhorns and a Cassegrain telescope, as key steps toward a complete 3.5-THz integrated receiver system.
{"title":"Waveguide-integrated THz Quantum-Cascade Lasers for Atmospheric-Research Satellite Payloads","authors":"A. Valavanis, O. Auriacombe, T. Rawlings, Y. Han, S. Rea, M. Crook, C. Arena, D. Walker, D. Brooks, G. Yu, L. Li, A. Davies, G. Savini, E. Linfield, B. Ellison, E. Sáenz","doi":"10.1109/IEEE-IWS.2019.8803875","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803875","url":null,"abstract":"Terahertz-frequency quantum-cascade lasers (THz QCLs) are compact, electrically-driven sources of narrowband radiation in the ~2–5-THz band. Numerous scientifically important gas-phase species within the Earth’s upper atmosphere have distinctive spectral features within this band, making QCLs attractive sources for spectroscopic and radiometric atmospheric studies. In this paper, we demonstrate the integration of a QCL with a satellite-compliant cryocooler, precision-micromachined waveguide, a pair of diagonal feedhorns and a Cassegrain telescope, as key steps toward a complete 3.5-THz integrated receiver system.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126877681","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 : 2019-08-19DOI: 10.1109/IEEE-IWS.2019.8804154
Shaowei Dai, Minghui Li, Q. Abbasi, M. Imran
This paper presents a new structure and algorithm to improve the tracking speed of a Generalized Sidelobe Canceler (GSC) based adaptive beamformer. Iterative methods like Conjugate Gradient algorithm to calculate the beamformer weight vector eliminates the complexity of Matrix reversing. But the reduced complexity comes with time cost which requires iterations of calculation before converging to the desired direction. To combat the problem, a Simplified Zero Placement algorithm is proposed to set the initial weight vector to make the starting value near the optimum location of weight vector. Numerical simulation and analysis confirms the effectiveness of the proposed solution.
{"title":"Improve Tracking Speed of Beamformer With Simplified Zero Placement Algorithm","authors":"Shaowei Dai, Minghui Li, Q. Abbasi, M. Imran","doi":"10.1109/IEEE-IWS.2019.8804154","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804154","url":null,"abstract":"This paper presents a new structure and algorithm to improve the tracking speed of a Generalized Sidelobe Canceler (GSC) based adaptive beamformer. Iterative methods like Conjugate Gradient algorithm to calculate the beamformer weight vector eliminates the complexity of Matrix reversing. But the reduced complexity comes with time cost which requires iterations of calculation before converging to the desired direction. To combat the problem, a Simplified Zero Placement algorithm is proposed to set the initial weight vector to make the starting value near the optimum location of weight vector. Numerical simulation and analysis confirms the effectiveness of the proposed solution.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132744209","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}
A compact dual-polarized patch antenna loaded with metamaterial unit cell is presented in this paper for broadband wireless communication systems. The unit cell is composed of two crossed open loop resonators, which are printed on the crossed substrates. Thanks to the loading of the unit cell, a compact patch antenna is realized with two reflection zeroes. The antenna is driven by the differential ports to obtain high isolation and low cross-polarization. The proposed antenna was fabricated and measured for verification. Measured results show that the proposed antenna has the impedance bandwidth of 17 % for S11 < −10 dB with the cross polarization lower than -33 dB. Both the simulated and measured results prove that the proposed antenna can be a good candidate for the wireless communication.
{"title":"A Compact Dual-Polarized Patch Antenna Loaded With Metamaterial Unit Cell for Broadband Wireless Communication","authors":"Lehu Wen, S. Gao, Qingling Yang, Q. Luo, Xiaofei Ren, Jian Wu","doi":"10.1109/IEEE-IWS.2019.8804152","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804152","url":null,"abstract":"A compact dual-polarized patch antenna loaded with metamaterial unit cell is presented in this paper for broadband wireless communication systems. The unit cell is composed of two crossed open loop resonators, which are printed on the crossed substrates. Thanks to the loading of the unit cell, a compact patch antenna is realized with two reflection zeroes. The antenna is driven by the differential ports to obtain high isolation and low cross-polarization. The proposed antenna was fabricated and measured for verification. Measured results show that the proposed antenna has the impedance bandwidth of 17 % for S11 < −10 dB with the cross polarization lower than -33 dB. Both the simulated and measured results prove that the proposed antenna can be a good candidate for the wireless communication.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"102 15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128285795","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 : 2019-08-19DOI: 10.1109/IEEE-IWS.2019.8804072
Jeppe Bro Kristensen, Michel Massanet Ginard, O. K. Jensen, M. Shen
This paper presents a Non-Line-Of-Sight (NLOS) identification approach based on machine learning algorithms for ultra wide band positioning systems. The identification of NLOS conditions is crucial for positioning using trilateration as NLOS introduces positive biases in the calculated distances. The proposed method is based on the classification of the Channel Impulse Responses using Fisher’s Linear Discriminant and Support Vector Machines (SVM). The proposed approach has been validated by measurements in both an anechoic chamber where known reflections and obstacles are introduced and in a basement corridor as real environment scenario with more than 500 and 700 measured data sets for training, respectively. Results show an average identification accuracy of 92% for the case using SVM in the anechoic chamber and almost 100% for Fisher’s discriminant combined with SVM for the corridor scenario.
{"title":"Non-Line-of-Sight Identification for UWB Indoor Positioning Systems using Support Vector Machines","authors":"Jeppe Bro Kristensen, Michel Massanet Ginard, O. K. Jensen, M. Shen","doi":"10.1109/IEEE-IWS.2019.8804072","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804072","url":null,"abstract":"This paper presents a Non-Line-Of-Sight (NLOS) identification approach based on machine learning algorithms for ultra wide band positioning systems. The identification of NLOS conditions is crucial for positioning using trilateration as NLOS introduces positive biases in the calculated distances. The proposed method is based on the classification of the Channel Impulse Responses using Fisher’s Linear Discriminant and Support Vector Machines (SVM). The proposed approach has been validated by measurements in both an anechoic chamber where known reflections and obstacles are introduced and in a basement corridor as real environment scenario with more than 500 and 700 measured data sets for training, respectively. Results show an average identification accuracy of 92% for the case using SVM in the anechoic chamber and almost 100% for Fisher’s discriminant combined with SVM for the corridor scenario.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128153055","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 : 2019-05-22DOI: 10.1109/IEEE-IWS.2019.8804102
Xiaoyu Wang, Chao Yu, Yue Li, W. Hong, A. Zhu
In this paper, a single channel over-the-air (OTA) data acquisition approach for real-time calibration of digital predistorter in multiple-input multiple-output transmitters is proposed. By using the data acquired from the far-field OTA tests, the output of each power amplifier (PA) can be virtually reconstructed and thus the linearization reference at the main beam direction can be accurately estimated. Digital predistortion (DPD) can therefore be effectively constructed without direct measurement at PA output. Experimental results demonstrate that the proposed scheme can accurately estimate far-field main beam data and the proposed DPD can achieve excellent linearization performance.
{"title":"Real-Time Single Channel Over-the-Air Data Acquisition for Digital Predistortion of 5G Massive MIMO Wireless Transmitters","authors":"Xiaoyu Wang, Chao Yu, Yue Li, W. Hong, A. Zhu","doi":"10.1109/IEEE-IWS.2019.8804102","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804102","url":null,"abstract":"In this paper, a single channel over-the-air (OTA) data acquisition approach for real-time calibration of digital predistorter in multiple-input multiple-output transmitters is proposed. By using the data acquired from the far-field OTA tests, the output of each power amplifier (PA) can be virtually reconstructed and thus the linearization reference at the main beam direction can be accurately estimated. Digital predistortion (DPD) can therefore be effectively constructed without direct measurement at PA output. Experimental results demonstrate that the proposed scheme can accurately estimate far-field main beam data and the proposed DPD can achieve excellent linearization performance.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117197481","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8803903
Zhe Chen, D. Milosevic, P. Baltus, Hao Gao
This paper presents a co-design of Ka-band high-gain low-noise amplifier (LNA) integrated circuit (IC) and chip-on-board packaging for the 5G applications. In this high-gain Ka-band LNA, a dual-LC tank matching technique is applied at the input to achieve wide-band simultaneous noise and power matching. This LNA IC is implemented in a 0.25 µm SiGe BiC-MOS technology, and it is packaged in a chip-on-board technique. Therefore, this IC is co-designed with bond-wires and passive structures on the printed circuit board. The measured results show that this LNA chip provides 28 dB peak gain at 32 GHz and larger than 20 dB power gain from 27 to 35 GHz. The in-band noise figure is between 3.1 and 4.1 dB. After packing, the packaged amplifier can deliver 19 dB power gain and 5.6 dB NF at 29 GHz.
{"title":"Co-Design of a Ka-Band High-Gain Low-Noise Amplifier and Chip-on-Board Packaging","authors":"Zhe Chen, D. Milosevic, P. Baltus, Hao Gao","doi":"10.1109/IEEE-IWS.2019.8803903","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803903","url":null,"abstract":"This paper presents a co-design of Ka-band high-gain low-noise amplifier (LNA) integrated circuit (IC) and chip-on-board packaging for the 5G applications. In this high-gain Ka-band LNA, a dual-LC tank matching technique is applied at the input to achieve wide-band simultaneous noise and power matching. This LNA IC is implemented in a 0.25 µm SiGe BiC-MOS technology, and it is packaged in a chip-on-board technique. Therefore, this IC is co-designed with bond-wires and passive structures on the printed circuit board. The measured results show that this LNA chip provides 28 dB peak gain at 32 GHz and larger than 20 dB power gain from 27 to 35 GHz. The in-band noise figure is between 3.1 and 4.1 dB. After packing, the packaged amplifier can deliver 19 dB power gain and 5.6 dB NF at 29 GHz.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115576508","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8804049
R. S. Zakariyya, Md Khalid Hossain Jewel, O. J. Famoriji, F. Lin
Error detection and error correction are one of the pillars of any communication system which serve as an error correction mechanism and improve signal quality. In this paper, we present a turbo channel coding algorithm for up-link transport channel in narrowband internet of things. The proposed channel coding uses 24-bit CRC syndrome calculator and turbo codes with a tail bit convolutional encoder to transmits NB-IoT packet date from MAC layer to physical layer over AWGN. In addition, we carried out performance analysis and simulation of the proposed algorithm in accordance with NB-IoT requirement specified by 3GPP standard.
{"title":"Channel Coding Analysis for NB-IoT Up-Link Transport Channel","authors":"R. S. Zakariyya, Md Khalid Hossain Jewel, O. J. Famoriji, F. Lin","doi":"10.1109/IEEE-IWS.2019.8804049","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804049","url":null,"abstract":"Error detection and error correction are one of the pillars of any communication system which serve as an error correction mechanism and improve signal quality. In this paper, we present a turbo channel coding algorithm for up-link transport channel in narrowband internet of things. The proposed channel coding uses 24-bit CRC syndrome calculator and turbo codes with a tail bit convolutional encoder to transmits NB-IoT packet date from MAC layer to physical layer over AWGN. In addition, we carried out performance analysis and simulation of the proposed algorithm in accordance with NB-IoT requirement specified by 3GPP standard.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116238975","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8803850
Qinghua Wang, W. Che, G. Monti, F. Mastri, M. Mongiardo
This paper analyzes the problem of maximizing the gains of a single transmitter–single receiver inductive resonant Wireless Power Transfer link (WPT). Two different approaches are considered and compared: the use of impedance matching networks and the use of additional resonators (relay elements). It is shown that, if from a theoretical point of view the two approaches are equivalent, in some practical cases the maximization of the gains by means of relays may not be feasible.
{"title":"On the Use of Matching Networks and Relays for Maximizing the Gains of IR WPT Links","authors":"Qinghua Wang, W. Che, G. Monti, F. Mastri, M. Mongiardo","doi":"10.1109/IEEE-IWS.2019.8803850","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803850","url":null,"abstract":"This paper analyzes the problem of maximizing the gains of a single transmitter–single receiver inductive resonant Wireless Power Transfer link (WPT). Two different approaches are considered and compared: the use of impedance matching networks and the use of additional resonators (relay elements). It is shown that, if from a theoretical point of view the two approaches are equivalent, in some practical cases the maximization of the gains by means of relays may not be feasible.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132954032","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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