Pub Date : 2006-07-02DOI: 10.1109/SPAWC.2006.346359
Cheng Wang, E. Au, R. Murch, V. Lau
Zero-forcing (ZF) detection is a simple and effective technique for retrieving multiple transmitted data streams at the receiver in multiple-input multiple-output (MIMO) wireless antenna systems. However the detection requires accurate channel state information (CSI) which may not be available in practice. In this paper, the impact of imperfect CSI on the performance of MIMO ZF receiver over uncorrelated Rayleigh flat fading channel is analytically assessed. In particular, tight approximation of the post-processing SNR distribution is derived and system performance in terms of outage probability and the BER of MPSK modulation is obtained in closed-form. The tightness of our analytical approximation is verified by the simulation results
{"title":"Closed-Form Outage Probability and BER of MIMO Zero-Forcing Receiver in the Presence of Imperfect CSI","authors":"Cheng Wang, E. Au, R. Murch, V. Lau","doi":"10.1109/SPAWC.2006.346359","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346359","url":null,"abstract":"Zero-forcing (ZF) detection is a simple and effective technique for retrieving multiple transmitted data streams at the receiver in multiple-input multiple-output (MIMO) wireless antenna systems. However the detection requires accurate channel state information (CSI) which may not be available in practice. In this paper, the impact of imperfect CSI on the performance of MIMO ZF receiver over uncorrelated Rayleigh flat fading channel is analytically assessed. In particular, tight approximation of the post-processing SNR distribution is derived and system performance in terms of outage probability and the BER of MPSK modulation is obtained in closed-form. The tightness of our analytical approximation is verified by the simulation results","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128113739","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346394
P. Anghel, G. Leus, Mostafa Kaveh
We propose a distributed space-time coding (DSTC) systems based on the Alamouti design. We discuss the limitations in the relay channel of the "out of the box" Alamouti scheme and the additional complexity required to overcome its loss of diversity. Using a bit error rate based antenna selection approach, we design DSTC systems with one regenerative relay that improve on the classical Alamouti scheme when utilized in a two-hop channel. We prove that the proposed one relay DSTC system collects the full diversity of the distributed MISO channel. We also introduce a less complex DSTC system in which the relaying energies depend on the error probabilities at the relays. Numerical results show that the proposed systems perform close to the error probability lower bound obtained by considering error-free reception at the relays
{"title":"A Full-Diversity Distributed Space-Time Coding System with Regenerative Relays","authors":"P. Anghel, G. Leus, Mostafa Kaveh","doi":"10.1109/SPAWC.2006.346394","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346394","url":null,"abstract":"We propose a distributed space-time coding (DSTC) systems based on the Alamouti design. We discuss the limitations in the relay channel of the \"out of the box\" Alamouti scheme and the additional complexity required to overcome its loss of diversity. Using a bit error rate based antenna selection approach, we design DSTC systems with one regenerative relay that improve on the classical Alamouti scheme when utilized in a two-hop channel. We prove that the proposed one relay DSTC system collects the full diversity of the distributed MISO channel. We also introduce a less complex DSTC system in which the relaying energies depend on the error probabilities at the relays. Numerical results show that the proposed systems perform close to the error probability lower bound obtained by considering error-free reception at the relays","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128157162","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346437
Taiwen Tang, C. Chae, R. Heath, Sunghyun Cho
In this paper, a relaying strategy that uses multiple input multiple output (MIMO) fixed relays with linear processing for multiuser transmission in cellular networks is proposed. This approach applies to the two hop relaying scenario for coverage enhancement, where the base station transmits data to multiple users through one fixed relay (multiuser transmission). The fixed relay processes the received signal by applying a linear transformation and forwards the processed signal to multiple users. We propose an implementable multiuser precoding strategy that combines Tomlinson-Harashima precoding at the base station and linear signal processing at the relay with adaptive stream selection and QAM modulation. We propose a reduced complexity algorithm to select a subset of users to avoid an exhaustive search over all user permutations. Simulations illustrate the sum rate using Tomlinson-Harashima precoding without coding
{"title":"Tomlinson-Harashima Precoding with Adaptive Modulation for Fixed Relay Networks","authors":"Taiwen Tang, C. Chae, R. Heath, Sunghyun Cho","doi":"10.1109/SPAWC.2006.346437","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346437","url":null,"abstract":"In this paper, a relaying strategy that uses multiple input multiple output (MIMO) fixed relays with linear processing for multiuser transmission in cellular networks is proposed. This approach applies to the two hop relaying scenario for coverage enhancement, where the base station transmits data to multiple users through one fixed relay (multiuser transmission). The fixed relay processes the received signal by applying a linear transformation and forwards the processed signal to multiple users. We propose an implementable multiuser precoding strategy that combines Tomlinson-Harashima precoding at the base station and linear signal processing at the relay with adaptive stream selection and QAM modulation. We propose a reduced complexity algorithm to select a subset of users to avoid an exhaustive search over all user permutations. Simulations illustrate the sum rate using Tomlinson-Harashima precoding without coding","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121459490","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346373
J. Delmas, P. Comon, Y. Meurisse
This paper considers the problem of blind estimation of finite impulse responses (FIR) of single-input single-output (SISO) channels from second order statistics of transformed data, when the channel is excited by binary phase shift keying (BPSK), minimum shift keying (MSK) or quadrature phase shift keying (QPSK) inputs. Identifiability conditions are derived by considering that noncircularity induces diversity. Performance issues are also addressed by using standard subspace-based estimators, with benchmarks such as asymptotically minimum variance (AMV) bounds based on different statistics
{"title":"Identifiability of BPSK, MSK and QPSK FIR SISO Channels from Modified Second-Order Statistics","authors":"J. Delmas, P. Comon, Y. Meurisse","doi":"10.1109/SPAWC.2006.346373","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346373","url":null,"abstract":"This paper considers the problem of blind estimation of finite impulse responses (FIR) of single-input single-output (SISO) channels from second order statistics of transformed data, when the channel is excited by binary phase shift keying (BPSK), minimum shift keying (MSK) or quadrature phase shift keying (QPSK) inputs. Identifiability conditions are derived by considering that noncircularity induces diversity. Performance issues are also addressed by using standard subspace-based estimators, with benchmarks such as asymptotically minimum variance (AMV) bounds based on different statistics","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128797742","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346419
H. Boche, M. Schubert
We analyze and compare two iterative algorithms for the joint optimization of powers and receive strategies in a multiuser network. The design goal is to minimize the total power while fulfilling individual QoS requirements. This problem can be solved by the fixed-point iteration proposed by Yates, (1995) as well as by a recently proposed matrix-based iteration (M. Schubert and H. Boche, 2006; H. Boche et al., 2005). It was observed in the literature that the matrix-based iteration has an excellent convergence speed. However, an analytical investigation of the convergence behavior has been an open problem so far. In this paper, we show that the matrix-based iteration performs better than the fixed-point iteration in each step, given the same initialization. The resulting sequence of power vectors is component-wise monotonic decreasing. We also show that the matrix-based iteration has super-linear convergence. If the underlying interference functions are smooth, then the algorithm even has quadratic convergence, whereas the convergence of the fixed-point iteration is only linear, and depends on the system load. This explains the convergence behavior observed from simulations
分析比较了多用户网络中功率和接收策略联合优化的两种迭代算法。设计目标是在满足单个QoS要求的同时最小化总功率。这个问题可以通过Yates(1995)提出的不动点迭代以及最近提出的基于矩阵的迭代(M. Schubert和H. Boche, 2006;H. Boche et al.， 2005)。从文献中观察到，基于矩阵的迭代具有优异的收敛速度。然而，对收敛性的分析研究至今仍是一个开放性问题。在本文中，我们证明了在初始化相同的情况下，基于矩阵的迭代在每一步中都优于定点迭代。所得的幂向量序列是分量单调递减的。我们还证明了基于矩阵的迭代具有超线性收敛性。如果底层干扰函数是光滑的，则该算法甚至具有二次收敛性，而不动点迭代的收敛性仅为线性，并且依赖于系统负载。这解释了从模拟中观察到的收敛行为
{"title":"Convergence Behavior of Matrix-Based Iterative Transceiver Optimization","authors":"H. Boche, M. Schubert","doi":"10.1109/SPAWC.2006.346419","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346419","url":null,"abstract":"We analyze and compare two iterative algorithms for the joint optimization of powers and receive strategies in a multiuser network. The design goal is to minimize the total power while fulfilling individual QoS requirements. This problem can be solved by the fixed-point iteration proposed by Yates, (1995) as well as by a recently proposed matrix-based iteration (M. Schubert and H. Boche, 2006; H. Boche et al., 2005). It was observed in the literature that the matrix-based iteration has an excellent convergence speed. However, an analytical investigation of the convergence behavior has been an open problem so far. In this paper, we show that the matrix-based iteration performs better than the fixed-point iteration in each step, given the same initialization. The resulting sequence of power vectors is component-wise monotonic decreasing. We also show that the matrix-based iteration has super-linear convergence. If the underlying interference functions are smooth, then the algorithm even has quadratic convergence, whereas the convergence of the fixed-point iteration is only linear, and depends on the system load. This explains the convergence behavior observed from simulations","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116088853","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346369
Jeng-Kuang Hwang, Yu-Lun Chiu, R. Chung
A high performance and computation efficient decision-feedback receiver for M-ary bi-orthogonal keying (MBOK) direct-sequence ultra-wideband radio (DS-UWB) is proposed. First, an insightful vector-matrix signal model for UWB channel dispersion over many consecutive symbols is built up. Then, by modifying a baseline MBOK-RAKE receiver, we propose a novel RAKE with bidirectional decision feedback (RAKE-BDDF) receiver to efficiently cancel both the post-cursor and pre-cursor intersymbol interference (ISI) and multi-code interference (MCI) at symbol rate. Simulation results are included for 802.15.3a CM2 and CM4 UWB channels. It is seen that the RAKE-BDDF receiver can attain a performance close to the matched filter bound, with only a slight increase in the receiver complexity than that of the RAKE receiver
{"title":"A Novel Decision-Feedback Receiver for MBOK Direct Sequence Ultra-Wideband Radio","authors":"Jeng-Kuang Hwang, Yu-Lun Chiu, R. Chung","doi":"10.1109/SPAWC.2006.346369","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346369","url":null,"abstract":"A high performance and computation efficient decision-feedback receiver for M-ary bi-orthogonal keying (MBOK) direct-sequence ultra-wideband radio (DS-UWB) is proposed. First, an insightful vector-matrix signal model for UWB channel dispersion over many consecutive symbols is built up. Then, by modifying a baseline MBOK-RAKE receiver, we propose a novel RAKE with bidirectional decision feedback (RAKE-BDDF) receiver to efficiently cancel both the post-cursor and pre-cursor intersymbol interference (ISI) and multi-code interference (MCI) at symbol rate. Simulation results are included for 802.15.3a CM2 and CM4 UWB channels. It is seen that the RAKE-BDDF receiver can attain a performance close to the matched filter bound, with only a slight increase in the receiver complexity than that of the RAKE receiver","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115338129","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346436
J. M. Huerta, Josep Vidal
The position estimation accuracy is severely impaired by the nonline of sight (NLOS) effect present in urban scenarios. When estimating the position of a mobile terminal (MT) using some base stations (BS), it is of vital importance to know which ones are in NLOS with the MT. The present document shows a dual tracker system to follow the LOS-NLOS situations and the position of a MT. The first tracker provides an estimation of the probability of being at each situation. This information is used by the second tracker, an improved unscented Kalman filter, to weight the information from each BS to enhance the final positioning accuracy. The approach is tested under a real scenario with severe NLOS conditions and with a limited number of available BS
{"title":"LOS-NLOS Situation Tracking for Positioning Systems","authors":"J. M. Huerta, Josep Vidal","doi":"10.1109/SPAWC.2006.346436","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346436","url":null,"abstract":"The position estimation accuracy is severely impaired by the nonline of sight (NLOS) effect present in urban scenarios. When estimating the position of a mobile terminal (MT) using some base stations (BS), it is of vital importance to know which ones are in NLOS with the MT. The present document shows a dual tracker system to follow the LOS-NLOS situations and the position of a MT. The first tracker provides an estimation of the probability of being at each situation. This information is used by the second tracker, an improved unscented Kalman filter, to weight the information from each BS to enhance the final positioning accuracy. The approach is tested under a real scenario with severe NLOS conditions and with a limited number of available BS","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114391293","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346393
B. Krongold
Orthogonal frequency-division multiple access (OFDMA) technology is being considered for uplink (UL) transmission in future mobile standards. While such systems can enjoy the advantages of OFDM, it also shares its disadvantages, and in particular, a large peak-to-average power ratio (PAR). PAR reduction techniques can be employed, but with a fraction of the bandwidth used by each user, the UL-OFDMA scenario is different than for traditional OFDM systems. Tone reservation has been proposed as one technique in recent 3GPP standards meetings, but in this paper, we offer more efficient algorithms that are well-suited for the UL-OFDMA case and easily incorporate any necessary power-spectral density (PSD) constraints
{"title":"PAR Reduction in the Uplink for OFDMA Systems","authors":"B. Krongold","doi":"10.1109/SPAWC.2006.346393","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346393","url":null,"abstract":"Orthogonal frequency-division multiple access (OFDMA) technology is being considered for uplink (UL) transmission in future mobile standards. While such systems can enjoy the advantages of OFDM, it also shares its disadvantages, and in particular, a large peak-to-average power ratio (PAR). PAR reduction techniques can be employed, but with a fraction of the bandwidth used by each user, the UL-OFDMA scenario is different than for traditional OFDM systems. Tone reservation has been proposed as one technique in recent 3GPP standards meetings, but in this paper, we offer more efficient algorithms that are well-suited for the UL-OFDMA case and easily incorporate any necessary power-spectral density (PSD) constraints","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114694548","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346407
H. Kulatunga, V. Kadirkamanathan
A joint decoding method for space-time block codes is presented. The space-time coded signals can be viewed as a first-order Markov chain, permitting the development of a multiple model algorithm. Therefore the quasi-static assumption can be relaxed and joint channel and symbol estimation is carried out at each time-instant as opposed to at the end of a block duration
{"title":"Space-Time Block Coding: Joint Detection and Channel Estimation using Multiple Model Theory","authors":"H. Kulatunga, V. Kadirkamanathan","doi":"10.1109/SPAWC.2006.346407","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346407","url":null,"abstract":"A joint decoding method for space-time block codes is presented. The space-time coded signals can be viewed as a first-order Markov chain, permitting the development of a multiple model algorithm. Therefore the quasi-static assumption can be relaxed and joint channel and symbol estimation is carried out at each time-instant as opposed to at the end of a block duration","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122736995","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 : 2006-07-02DOI: 10.1109/SPAWC.2006.346439
A. Bastug, D. Slock
We consider iterative WCDMA receiver techniques for the UMTS FDD downlink. The popular LMMSE chip equalizer-correlator receiver does not exploit subspaces in partially loaded systems. This is in contrast to the symbol level LMMSE receiver, which is time-varying though, due to the scrambler, and hence too complex to implement. A compromise can be found by performing symbol level multi-stage Wiener filtering (MSWF), which is an iterative solution in which the complexity per iteration becomes comparable to twice that of the RAKE receiver. Since the MSWF works best when the input is white, better performance is obtained if the RAKE in each MSWF stage gets replaced by a chip equalizer-correlator. One of the main contributions here is to point out that the chip equalizer benefits from a separate optimization in every stage. This is shown through a mix of analysis and simulation results
{"title":"Optimization Combined Chip and Symbol Level Equalization for Downlink WCDMA Reception","authors":"A. Bastug, D. Slock","doi":"10.1109/SPAWC.2006.346439","DOIUrl":"https://doi.org/10.1109/SPAWC.2006.346439","url":null,"abstract":"We consider iterative WCDMA receiver techniques for the UMTS FDD downlink. The popular LMMSE chip equalizer-correlator receiver does not exploit subspaces in partially loaded systems. This is in contrast to the symbol level LMMSE receiver, which is time-varying though, due to the scrambler, and hence too complex to implement. A compromise can be found by performing symbol level multi-stage Wiener filtering (MSWF), which is an iterative solution in which the complexity per iteration becomes comparable to twice that of the RAKE receiver. Since the MSWF works best when the input is white, better performance is obtained if the RAKE in each MSWF stage gets replaced by a chip equalizer-correlator. One of the main contributions here is to point out that the chip equalizer benefits from a separate optimization in every stage. This is shown through a mix of analysis and simulation results","PeriodicalId":414942,"journal":{"name":"2006 IEEE 7th Workshop on Signal Processing Advances in Wireless Communications","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116618486","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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