Pub Date : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803860
Lin Wang, Y. Chang, Bo Li, Peng Zhang
In this paper, a new design of multi-band artificial magnetic conductor (AMC) is proposed, which the electromagnetic band gaps are realized through four PIN diodes. By controlling the states of the diodes between "OFF" and "ON", the in-phase reflection frequency of the AMC can switch from 2.85GHz/4.25GHz to 5.2GHz. Equivalent circuit of the proposed AMC structure is given in this work. With detailed analysis of the Electric field distributions on the structure, one can clearly find the mechanism of the appearances of the multi in-phase reflection frequencies. Meanwhile, the bandwidth for each band is 13.33%, 4.23% and 4.81% respectively.
{"title":"Reconfigurable AMC Structure based on Multimode Resonances","authors":"Lin Wang, Y. Chang, Bo Li, Peng Zhang","doi":"10.1109/IEEE-IWS.2019.8803860","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803860","url":null,"abstract":"In this paper, a new design of multi-band artificial magnetic conductor (AMC) is proposed, which the electromagnetic band gaps are realized through four PIN diodes. By controlling the states of the diodes between \"OFF\" and \"ON\", the in-phase reflection frequency of the AMC can switch from 2.85GHz/4.25GHz to 5.2GHz. Equivalent circuit of the proposed AMC structure is given in this work. With detailed analysis of the Electric field distributions on the structure, one can clearly find the mechanism of the appearances of the multi in-phase reflection frequencies. Meanwhile, the bandwidth for each band is 13.33%, 4.23% and 4.81% respectively.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133816323","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803845
Mengchu Fang, Xiao Xu, T. Yoshimasu
A low-supply-voltage 15-GHz-band LC-VCO IC is presented in this paper to improve the phase noise and FoM performance. The proposed VCO IC adopts a drain harmonic tuned filter and an LC bias circuit to realize high load impedance at the third harmonics and to amplify carrier signal for improving the phase noise performance. The LC-VCO IC is designed, fabricated and fully evaluated on wafer in 40-nm SOI CMOS. The fabricated VCO IC has exhibited a measured phase noise of −132.0 dBc/Hz at 10-MHz offset frequency from the 15.58 GHz carrier frequency and a measured FoMT of −197.5 dBc/Hz with a supply voltage of 0.45 V.
{"title":"A Low Supply Voltage LC-VCO IC with a Drain Harmonic Tuned Filter in 40-nm SOI CMOS","authors":"Mengchu Fang, Xiao Xu, T. Yoshimasu","doi":"10.1109/IEEE-IWS.2019.8803845","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803845","url":null,"abstract":"A low-supply-voltage 15-GHz-band LC-VCO IC is presented in this paper to improve the phase noise and FoM performance. The proposed VCO IC adopts a drain harmonic tuned filter and an LC bias circuit to realize high load impedance at the third harmonics and to amplify carrier signal for improving the phase noise performance. The LC-VCO IC is designed, fabricated and fully evaluated on wafer in 40-nm SOI CMOS. The fabricated VCO IC has exhibited a measured phase noise of −132.0 dBc/Hz at 10-MHz offset frequency from the 15.58 GHz carrier frequency and a measured FoMT of −197.5 dBc/Hz with a supply voltage of 0.45 V.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132721913","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8804007
Hui-Wen Hung, P. Baltus, Hao Gao, F. Bruccoleri, K. van Hartingsveldt, K. Kianush
There is a great increasing demand to embed GNSS receivers on portable devices, because they can provide much higher positioning accuracy and better availability compared with GPS-only receivers. However, portable devices have strong limitations on power consumption and area. In order to realize a low power and compact GNSS receiver, this paper presents both system level and circuit level solutions. In the system level, a two-state GNSS receiver architecture is introduced with acquisition phase and tracking phase to optimize the power consumption. In the circuit level, a dual-mode inductorless LNTA with adaptive bias and with an active inductor for gain boosting is proposed. This LNTA is designed and layout in a 40nm CMOS technology.
{"title":"An Inductorless Power-Optimized Dual-Mode LNTA in a GNSS Receiver for Portable Devices","authors":"Hui-Wen Hung, P. Baltus, Hao Gao, F. Bruccoleri, K. van Hartingsveldt, K. Kianush","doi":"10.1109/IEEE-IWS.2019.8804007","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804007","url":null,"abstract":"There is a great increasing demand to embed GNSS receivers on portable devices, because they can provide much higher positioning accuracy and better availability compared with GPS-only receivers. However, portable devices have strong limitations on power consumption and area. In order to realize a low power and compact GNSS receiver, this paper presents both system level and circuit level solutions. In the system level, a two-state GNSS receiver architecture is introduced with acquisition phase and tracking phase to optimize the power consumption. In the circuit level, a dual-mode inductorless LNTA with adaptive bias and with an active inductor for gain boosting is proposed. This LNTA is designed and layout in a 40nm CMOS technology.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"300 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133710291","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803847
Songhu Ge, Hongbo Liu, Yongcai Liu, Jinling Xing, Jin Meng
In this paper, a baseband digital canceller is designed and implemented to cancel the co-site interference. Especially, in order to achieve high-speed low-latency cancellation performance, a transposed form retimed delayed LMS (TF-RDLMS) filter structure is introduced and extended to complex signal form. In the proposed complex TF-RDLMS filter, the basic Processing Module (PM) is established with a set of real cross-coupling signal flows. Then, the canceller is implemented with Xilinx field programmable gate array (FPGA) chip by cascading several PMs. Finally, the validity and effectiveness of the implemented canceller is confirmed by experimental results. It is shown that the canceller can achieve 31 dB and 27 dB cancellation performance for 5 MHz and 10 MHz interference signal, respectively.
{"title":"Design and Implementation of A Real-time Baseband Adaptive Digital Interference Canceller","authors":"Songhu Ge, Hongbo Liu, Yongcai Liu, Jinling Xing, Jin Meng","doi":"10.1109/IEEE-IWS.2019.8803847","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803847","url":null,"abstract":"In this paper, a baseband digital canceller is designed and implemented to cancel the co-site interference. Especially, in order to achieve high-speed low-latency cancellation performance, a transposed form retimed delayed LMS (TF-RDLMS) filter structure is introduced and extended to complex signal form. In the proposed complex TF-RDLMS filter, the basic Processing Module (PM) is established with a set of real cross-coupling signal flows. Then, the canceller is implemented with Xilinx field programmable gate array (FPGA) chip by cascading several PMs. Finally, the validity and effectiveness of the implemented canceller is confirmed by experimental results. It is shown that the canceller can achieve 31 dB and 27 dB cancellation performance for 5 MHz and 10 MHz interference signal, respectively.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122490908","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803985
Chang Liu, Hao Luo, Guoqiang Zhao, Houjun Sun
An omnidirectional circularly polarized (CP) antenna operating in W-band is proposed. The antenna has a simple structure, which consists of a dual-reflector antenna, an ortho-mode transducer (OMT) and a 3-dB coupler. The OMT adopts a novel septum-free structure, and can realize wideband, high isolation, and low loss. The results show that the dual-reflector antenna with this OMT has an impedance bandwidth from 91.1 to 96.8 GHz (the overlapped bandwidth limited by |S11| < -15dB, |S22|< -15dB) and a 3-dB axial-ratio bandwidth from 93.1 to 95.9 GHz. In addition, the omnidirectional CP radiation pattern can be obtained in the azimuth plane of θ = 40°- 80°.
{"title":"Design of a W-band Omnidirectional Circularly Polarized Antenna by Using OMT","authors":"Chang Liu, Hao Luo, Guoqiang Zhao, Houjun Sun","doi":"10.1109/IEEE-IWS.2019.8803985","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803985","url":null,"abstract":"An omnidirectional circularly polarized (CP) antenna operating in W-band is proposed. The antenna has a simple structure, which consists of a dual-reflector antenna, an ortho-mode transducer (OMT) and a 3-dB coupler. The OMT adopts a novel septum-free structure, and can realize wideband, high isolation, and low loss. The results show that the dual-reflector antenna with this OMT has an impedance bandwidth from 91.1 to 96.8 GHz (the overlapped bandwidth limited by |S11| < -15dB, |S22|< -15dB) and a 3-dB axial-ratio bandwidth from 93.1 to 95.9 GHz. In addition, the omnidirectional CP radiation pattern can be obtained in the azimuth plane of θ = 40°- 80°.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121761396","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803976
Jiale Yang, Gongan Qiu, Jin Shi
Multi-port filtering power dividing networks have been applied widely in modern communication systems due to their high integration level by fusing filtering function and power dividing function into one component. The reported filtering power dividing networks are realized by using filters cascading to power dividing network or using the two identical filtering structures symmetrically coupled to one input feed line, which always suffer from large circuit size. In this paper, three different methods for size reduction are reviewed, summarized and compared with each other, such as utilizing filtering structures to replace the quarter-wavelength transmission structures of power dividing network, using couplings between the four resonators formed in a ring-type coupling topology, as well as employing one filtering structure coupled with input/output feed lines. Each method is demonstrated by one specific case.
{"title":"Multi-port Filtering Power Dividing Networks","authors":"Jiale Yang, Gongan Qiu, Jin Shi","doi":"10.1109/IEEE-IWS.2019.8803976","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803976","url":null,"abstract":"Multi-port filtering power dividing networks have been applied widely in modern communication systems due to their high integration level by fusing filtering function and power dividing function into one component. The reported filtering power dividing networks are realized by using filters cascading to power dividing network or using the two identical filtering structures symmetrically coupled to one input feed line, which always suffer from large circuit size. In this paper, three different methods for size reduction are reviewed, summarized and compared with each other, such as utilizing filtering structures to replace the quarter-wavelength transmission structures of power dividing network, using couplings between the four resonators formed in a ring-type coupling topology, as well as employing one filtering structure coupled with input/output feed lines. Each method is demonstrated by one specific case.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114806666","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803919
Yu Gan, H. Meng, Yang Chen, Yanzhong Yu, W. Dou
In this paper, a discrete dielectric lens is presented. The proposed lens can convert an incident Gaussian beam in millimeter wave band to a plane wave. The unit cells of the transforming lens are cuboid elements drilled with air holes on dielectric substrate. The insertion phase distribution before and after the lens is calculated through the paraxial Gaussian beam formula and the phase shift is realized by different air hole radius and different substrate thickness. The 3D printing technology is employed to fabricate the lens. The results show that the plane wave transformed through the lens has very good performance. The gain is greater than 36.1dBi at 35GHz.
{"title":"Millimeter-Wave Beam Transforming Lens with 3D Printing Technology","authors":"Yu Gan, H. Meng, Yang Chen, Yanzhong Yu, W. Dou","doi":"10.1109/IEEE-IWS.2019.8803919","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803919","url":null,"abstract":"In this paper, a discrete dielectric lens is presented. The proposed lens can convert an incident Gaussian beam in millimeter wave band to a plane wave. The unit cells of the transforming lens are cuboid elements drilled with air holes on dielectric substrate. The insertion phase distribution before and after the lens is calculated through the paraxial Gaussian beam formula and the phase shift is realized by different air hole radius and different substrate thickness. The 3D printing technology is employed to fabricate the lens. The results show that the plane wave transformed through the lens has very good performance. The gain is greater than 36.1dBi at 35GHz.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116801593","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803988
Min Han, W. Dou
In this paper, an improved Capon estimator is introduced, and reserves the characteristics of signal space after filtering the noise. More precise power estimation for both noise and signal from different directions can be obtained. Then, the covariance matrices of both interference-plus-noise and signal are reconstructed. With the estimated noise power and the covariance matrices, we propose 4 similar algorithms. Different from the previous methods, the proposed algorithms avoid the robust conditions in the constraints, even to solve a new convex optimization problem which would increase the amount of computation significantly. Simulation results show that the improved Capon estimator achieves better spatial resolution than existing methods, and the performance of the proposed robust adaptive beamforming is almost close to the optimal value across a wide range of signal to interference and noise ratio.
{"title":"Unconstrained Robust Adaptive Beamforming with Improved Capon Estimator","authors":"Min Han, W. Dou","doi":"10.1109/IEEE-IWS.2019.8803988","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803988","url":null,"abstract":"In this paper, an improved Capon estimator is introduced, and reserves the characteristics of signal space after filtering the noise. More precise power estimation for both noise and signal from different directions can be obtained. Then, the covariance matrices of both interference-plus-noise and signal are reconstructed. With the estimated noise power and the covariance matrices, we propose 4 similar algorithms. Different from the previous methods, the proposed algorithms avoid the robust conditions in the constraints, even to solve a new convex optimization problem which would increase the amount of computation significantly. Simulation results show that the improved Capon estimator achieves better spatial resolution than existing methods, and the performance of the proposed robust adaptive beamforming is almost close to the optimal value across a wide range of signal to interference and noise ratio.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125407788","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803995
Donghao Li, K. Xu
A fifth-order bandpass filter (BPF) using three pairs of coupled lines and two shorted stepped-impedance stubs is proposed in this paper. Five transmission poles (TPs) within the passband and six deep transmission zeros (TZs) from 0 to 2f0 (f0:passband center frequency) can be realized through input admittance calculation. For demonstration, a sharp roll-off BPF prototype centered at 2 GHz with good in-band characteristics (insertion losses and return losses) and high stopband rejections is designed, whose 3-dB fractional bandwidth is of 34%.
{"title":"Sharp Roll-Off Bandpass Filter Using Coupled Lines and Stepped-Impedance Stubs","authors":"Donghao Li, K. Xu","doi":"10.1109/IEEE-IWS.2019.8803995","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803995","url":null,"abstract":"A fifth-order bandpass filter (BPF) using three pairs of coupled lines and two shorted stepped-impedance stubs is proposed in this paper. Five transmission poles (TPs) within the passband and six deep transmission zeros (TZs) from 0 to 2f0 (f0:passband center frequency) can be realized through input admittance calculation. For demonstration, a sharp roll-off BPF prototype centered at 2 GHz with good in-band characteristics (insertion losses and return losses) and high stopband rejections is designed, whose 3-dB fractional bandwidth is of 34%.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122390147","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 : 2019-05-01DOI: 10.1109/IEEE-IWS.2019.8803934
Dajiang Li, M. Tang, Xiaoming Chen, Yang Wang, Kun‐Zhi Hu, R. Ziolkowski
A planar, wideband, multi-polarization reconfigurable filtering antenna is proposed. By controlling the state of PIN diodes, the operation states of the filtering antenna can be switched among linear polarization (LP), left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP). The filtering antenna consists of a driven patch, a parasitic patch, and an established reconfigurable feed network. Two radiation nulls can be generated at the lower and upper band-edge in all operation states through interaction between the driven patch and feeding network. A pair of U-slots is etched on the driven patch to obtain the extra radiation null to further improve the sharp roll-off rate at the upper band-edge. The optimized prototype was fabricated and tested. The measured results, in good agreement with the simulated values, demonstrate that the filtenna has a wide -10dB fractional bandwidth: 15.6%, a realized gain value over operational bandwidth of 7.7 ± 0.5 dBi, and stable radiation performance. Furthermore, the filtenna presents a good out-of-band rejection level.
{"title":"Design of Planar, Wideband, Multi-Polarization Reconfigurable Filtering Antenna","authors":"Dajiang Li, M. Tang, Xiaoming Chen, Yang Wang, Kun‐Zhi Hu, R. Ziolkowski","doi":"10.1109/IEEE-IWS.2019.8803934","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803934","url":null,"abstract":"A planar, wideband, multi-polarization reconfigurable filtering antenna is proposed. By controlling the state of PIN diodes, the operation states of the filtering antenna can be switched among linear polarization (LP), left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP). The filtering antenna consists of a driven patch, a parasitic patch, and an established reconfigurable feed network. Two radiation nulls can be generated at the lower and upper band-edge in all operation states through interaction between the driven patch and feeding network. A pair of U-slots is etched on the driven patch to obtain the extra radiation null to further improve the sharp roll-off rate at the upper band-edge. The optimized prototype was fabricated and tested. The measured results, in good agreement with the simulated values, demonstrate that the filtenna has a wide -10dB fractional bandwidth: 15.6%, a realized gain value over operational bandwidth of 7.7 ± 0.5 dBi, and stable radiation performance. Furthermore, the filtenna presents a good out-of-band rejection level.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130944691","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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