Pub Date : 2005-09-11DOI: 10.1109/PIMRC.2005.1651823
G. Manfredi, P. Annese, U. Spagnolini
High speed downlink packet access (HSDPA) is an evolutionary step to boost the WCDMA performance for downlink packet traffic as it increases spectral efficiency by supporting high user data rates. Because of the time varying channel fluctuations of wireless links, efficient use of the large available bandwidth cannot be achieved without adopting channel aware packet scheduling strategies. The HSDPA scheduling algorithm is based on splitting the scheduling decision into user selection and resource allocation. In this paper, we propose two user selection algorithms that can be adjusted (or pre-configured) in terms of cell throughput and/or user throughput fairness. Finally, we discuss a channel aware resource allocation algorithm that aims to maximize the number of served users among the selected ones, without any loss of the overall cell throughput with respect to the traditional greedy resource assignment
{"title":"A channel aware scheduling algorithm for HSDPA system","authors":"G. Manfredi, P. Annese, U. Spagnolini","doi":"10.1109/PIMRC.2005.1651823","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651823","url":null,"abstract":"High speed downlink packet access (HSDPA) is an evolutionary step to boost the WCDMA performance for downlink packet traffic as it increases spectral efficiency by supporting high user data rates. Because of the time varying channel fluctuations of wireless links, efficient use of the large available bandwidth cannot be achieved without adopting channel aware packet scheduling strategies. The HSDPA scheduling algorithm is based on splitting the scheduling decision into user selection and resource allocation. In this paper, we propose two user selection algorithms that can be adjusted (or pre-configured) in terms of cell throughput and/or user throughput fairness. Finally, we discuss a channel aware resource allocation algorithm that aims to maximize the number of served users among the selected ones, without any loss of the overall cell throughput with respect to the traditional greedy resource assignment","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128622956","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651561
M. Bengtsson, D. Bartolomé, J. Vicario, C. Antón-Haro
In this paper, we address the problem of transmit beamforming, power allocation, bit loading, and admission control in a multi-user scenario, where several single antenna mobile terminals are served by one base station equipped with an antenna array. In particular, we explore the impact of using either optimal or zero-forcing transmit beamforming schemes in combination with different bit allocation strategies, namely the maximization of the sum rate (MSR), the maximization of the minimum rate (MMR) and a modified version of the latter, for a finite set of modulation schemes. The performance evaluation is conducted by means of system-level simulations, using a realistic channel model for urban micro cells, with an emphasis not only on the aggregated cell throughput but also on the associated fairness issues
{"title":"Beamforming and bit-loading strategies for multi-user SDMA with admission control","authors":"M. Bengtsson, D. Bartolomé, J. Vicario, C. Antón-Haro","doi":"10.1109/PIMRC.2005.1651561","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651561","url":null,"abstract":"In this paper, we address the problem of transmit beamforming, power allocation, bit loading, and admission control in a multi-user scenario, where several single antenna mobile terminals are served by one base station equipped with an antenna array. In particular, we explore the impact of using either optimal or zero-forcing transmit beamforming schemes in combination with different bit allocation strategies, namely the maximization of the sum rate (MSR), the maximization of the minimum rate (MMR) and a modified version of the latter, for a finite set of modulation schemes. The performance evaluation is conducted by means of system-level simulations, using a realistic channel model for urban micro cells, with an emphasis not only on the aggregated cell throughput but also on the associated fairness issues","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129840358","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}
In 3G WCDMA, several multi-code assignment mechanisms have proposed to reduce the waste rate. Nevertheless, these methods bring two inevitable drawbacks including, high complexity of handling multiple codes, and increasing the cost of using more rake combiners at both the base stations and mobile nodes. Therefore, we propose an adaptive grouping code assignment herein to provide a single channelization code for any possible rate of traffic, even though the required rate is not powers of two of the basic rate. Based on the dynamic programming algorithm, the adaptive grouping approach forms several calls into a group. Then it allocates a subtree to the group and adaptively shares the subtree codes for these calls in the concept of time-sharing of slots during a group cycle time. Numerical results indicate that the proposed adaptive grouping approach reduces significantly the waste rate and thus increases the system utilization
{"title":"Adaptive Time-sharing Based Grouping Code Assignment in Mobile WCDMA Networks","authors":"Ben-Jye Chang, Min-Xiou Chen, Ren-Hung Hwang, Kun-Chan Tsai","doi":"10.1109/PIMRC.2005.1651455","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651455","url":null,"abstract":"In 3G WCDMA, several multi-code assignment mechanisms have proposed to reduce the waste rate. Nevertheless, these methods bring two inevitable drawbacks including, high complexity of handling multiple codes, and increasing the cost of using more rake combiners at both the base stations and mobile nodes. Therefore, we propose an adaptive grouping code assignment herein to provide a single channelization code for any possible rate of traffic, even though the required rate is not powers of two of the basic rate. Based on the dynamic programming algorithm, the adaptive grouping approach forms several calls into a group. Then it allocates a subtree to the group and adaptively shares the subtree codes for these calls in the concept of time-sharing of slots during a group cycle time. Numerical results indicate that the proposed adaptive grouping approach reduces significantly the waste rate and thus increases the system utilization","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126900662","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651852
M. Rezaei, S. Wenger, M. Gabbouj
In this paper, we propose a real-time, low-complexity video rate control algorithm designed to obey buffer constraints. The algorithm is optimized for streaming and local recording applications in mobile devices. Today, most mobile phones include a digital camera that can be used to capture video. The on-phone processor technology has become powerful enough to encode video in real-time. The resulting file can, for example, be archived in the phone's memory, or (progressively or as one block) downloaded, through the 3G mobile network, Bluetooth, or WLAN, to Internet-connected computer systems. From here, all forms of multimedia transmission, such as streaming, file sharing, or multimedia mail become possible. In local recording and streaming applications on a mobile phone, we assume that no memory for storage of uncompressed video is available. Therefore, look-ahead and multi-path rate control is not possible. Furthermore, considering the processing power and, more importantly, battery life constraints in mobile devices, the proposed algorithm needs to be as simple as possible. The described algorithm implements a variable bitrate (VBR) by controlling the quantization scale (QS) on a per picture basis. The QS is calculated based on two other QSs, which correspond to constant rate and constant quality rate controls. The algorithm utilizes the variable bitrate benefits as much as possible so as to minimize the variation of the QS scale, and to provide encoded video with high visual quality. Although it strictly obeys buffering constraints as discussed later, the experimental results show that it allows encoded video at average quality levels significantly higher than reported in earlier works
{"title":"Video rate control for streaming and local recording optimized for mobile devices","authors":"M. Rezaei, S. Wenger, M. Gabbouj","doi":"10.1109/PIMRC.2005.1651852","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651852","url":null,"abstract":"In this paper, we propose a real-time, low-complexity video rate control algorithm designed to obey buffer constraints. The algorithm is optimized for streaming and local recording applications in mobile devices. Today, most mobile phones include a digital camera that can be used to capture video. The on-phone processor technology has become powerful enough to encode video in real-time. The resulting file can, for example, be archived in the phone's memory, or (progressively or as one block) downloaded, through the 3G mobile network, Bluetooth, or WLAN, to Internet-connected computer systems. From here, all forms of multimedia transmission, such as streaming, file sharing, or multimedia mail become possible. In local recording and streaming applications on a mobile phone, we assume that no memory for storage of uncompressed video is available. Therefore, look-ahead and multi-path rate control is not possible. Furthermore, considering the processing power and, more importantly, battery life constraints in mobile devices, the proposed algorithm needs to be as simple as possible. The described algorithm implements a variable bitrate (VBR) by controlling the quantization scale (QS) on a per picture basis. The QS is calculated based on two other QSs, which correspond to constant rate and constant quality rate controls. The algorithm utilizes the variable bitrate benefits as much as possible so as to minimize the variation of the QS scale, and to provide encoded video with high visual quality. Although it strictly obeys buffering constraints as discussed later, the experimental results show that it allows encoded video at average quality levels significantly higher than reported in earlier works","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123661620","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651614
E. Strinati, S. Simoens, J. Boutros
This paper deals with packet error rate (PER) prediction and its impact on adaptive modulation and coding (AMC) for an OFDM turbo coded transmission on a multipath channel. We compare four link quality metrics (LQM), including the signal to noise ratio (SNR), the capacity, and two LQM which we designed to exploit the soft outputs of the turbo-decoder. Since error prediction is used to perform AMC, we assess the throughput performance of a realistic system employing each of the four LQM. The comparison shows that while SNR performs poorly and capacity remains suboptimum, the two metrics exploiting soft outputs approach the throughput which would be achieved by perfect PER prediction
{"title":"New error prediction techniques for turbo-coded OFDM systems and impact on adaptive modulation and coding","authors":"E. Strinati, S. Simoens, J. Boutros","doi":"10.1109/PIMRC.2005.1651614","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651614","url":null,"abstract":"This paper deals with packet error rate (PER) prediction and its impact on adaptive modulation and coding (AMC) for an OFDM turbo coded transmission on a multipath channel. We compare four link quality metrics (LQM), including the signal to noise ratio (SNR), the capacity, and two LQM which we designed to exploit the soft outputs of the turbo-decoder. Since error prediction is used to perform AMC, we assess the throughput performance of a realistic system employing each of the four LQM. The comparison shows that while SNR performs poorly and capacity remains suboptimum, the two metrics exploiting soft outputs approach the throughput which would be achieved by perfect PER prediction","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"253 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123682141","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651643
A. Mallahzadeh, M. Khajehpour
A ridged circular patch antenna element excited by a transmission line proximity method is analyzed. The approach is based on conserving the reaction at the ridged position using the cavity model with the assumption of a linear variation of the current distribution on the overlap region of the line and the patch. For a given thickness and patch radius, the smallest line to ground plane spacing for which the radiator is matched to the line is found. Finally, our results are compared with measured data
{"title":"The ridged circular disk microstrip antenna element excited by a microstrip transmission line proximity method","authors":"A. Mallahzadeh, M. Khajehpour","doi":"10.1109/PIMRC.2005.1651643","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651643","url":null,"abstract":"A ridged circular patch antenna element excited by a transmission line proximity method is analyzed. The approach is based on conserving the reaction at the ridged position using the cavity model with the assumption of a linear variation of the current distribution on the overlap region of the line and the patch. For a given thickness and patch radius, the smallest line to ground plane spacing for which the radiator is matched to the line is found. Finally, our results are compared with measured data","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"14 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123684797","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651540
N. Tönder, H. Rohling
In this paper, orthogonal frequency division multiplexing (OFDM) systems with coherent, incoherent and quasi-coherent demodulation schemes will be considered respectively. Resulting system performance figures will be compared in terms of bit error rate (BER) and hardware complexity. It is well known that non-differential modulation and coherent demodulation techniques have optimum BER performance but lead to a significantly increased system overhead due to pilot signals and system complexity due to channel estimation procedure. This paper describes differential modulation schemes, which do not require any radio channel estimation, and two related incoherent and quasi-coherent demodulation techniques. The resulting BER performance is nearly identical compared with coherent demodulation, but the computation complexity is drastically reduced. A field programmable gate array (FPGA) based experimental system has been developed, which is used for BER performance measurements and system complexity considerations
{"title":"DAPSK schemes for low-complexity OFDM systems","authors":"N. Tönder, H. Rohling","doi":"10.1109/PIMRC.2005.1651540","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651540","url":null,"abstract":"In this paper, orthogonal frequency division multiplexing (OFDM) systems with coherent, incoherent and quasi-coherent demodulation schemes will be considered respectively. Resulting system performance figures will be compared in terms of bit error rate (BER) and hardware complexity. It is well known that non-differential modulation and coherent demodulation techniques have optimum BER performance but lead to a significantly increased system overhead due to pilot signals and system complexity due to channel estimation procedure. This paper describes differential modulation schemes, which do not require any radio channel estimation, and two related incoherent and quasi-coherent demodulation techniques. The resulting BER performance is nearly identical compared with coherent demodulation, but the computation complexity is drastically reduced. A field programmable gate array (FPGA) based experimental system has been developed, which is used for BER performance measurements and system complexity considerations","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114011344","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651830
C. Guthy, J. Brehmer, W. Utschick
In bottom-up cross-layer optimization, each layer offers a set of feasible operation points to the layer above, enabling the application to decide which parameter setup is optimum. In this paper, the capabilities of the physical layer in a multi-user MISO system are described in terms of the users' outage probabilities. Optimum descriptions are given by sets of efficient outage probability tuples. We first derive a closed-form expression for a user's outage probability in the presence of multi-user interference. Next, the set of efficient outage probability tuples under a simplified SDMA transmit strategy is derived. We show how a good approximate description of the efficient set is found by equidistant sampling. Finally, the performance of the proposed transmit strategy is compared with an orthogonal multiple access scheme, demonstrating that optimum mode selection at the physical layer can lead to significant performance gains at the application layer
{"title":"Physical layer characterization of a multi-user MISO system by efficient outage probabilities","authors":"C. Guthy, J. Brehmer, W. Utschick","doi":"10.1109/PIMRC.2005.1651830","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651830","url":null,"abstract":"In bottom-up cross-layer optimization, each layer offers a set of feasible operation points to the layer above, enabling the application to decide which parameter setup is optimum. In this paper, the capabilities of the physical layer in a multi-user MISO system are described in terms of the users' outage probabilities. Optimum descriptions are given by sets of efficient outage probability tuples. We first derive a closed-form expression for a user's outage probability in the presence of multi-user interference. Next, the set of efficient outage probability tuples under a simplified SDMA transmit strategy is derived. We show how a good approximate description of the efficient set is found by equidistant sampling. Finally, the performance of the proposed transmit strategy is compared with an orthogonal multiple access scheme, demonstrating that optimum mode selection at the physical layer can lead to significant performance gains at the application layer","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127615405","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651909
T. Clevorn, F. Oldewurtel, S. Godtmann, P. Vary
We propose the application of iterative demodulation at a DVB-S2 receiver. The demodulation is improved by feedback of extrinsic information from the decoder of the LDPC channel code. The presented simulation results show an enhancement of about 0.3 dB, which is notable taking the gap to the Shannon limit into account. The additionally required computational demand is negligible and the receiver only needs to be slightly modified. With the unmodified transmitter the proposed scheme is completely standard compliant
{"title":"Iterative demodulation for DVB-S2","authors":"T. Clevorn, F. Oldewurtel, S. Godtmann, P. Vary","doi":"10.1109/PIMRC.2005.1651909","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651909","url":null,"abstract":"We propose the application of iterative demodulation at a DVB-S2 receiver. The demodulation is improved by feedback of extrinsic information from the decoder of the LDPC channel code. The presented simulation results show an enhancement of about 0.3 dB, which is notable taking the gap to the Shannon limit into account. The additionally required computational demand is negligible and the receiver only needs to be slightly modified. With the unmodified transmitter the proposed scheme is completely standard compliant","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127698626","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 : 2005-09-11DOI: 10.1109/PIMRC.2005.1651696
B. Zerlin, J. Brehmer, J. Nossek
Like numerous other applications, novel cross-layer optimization schemes require the determination of the outage probability of fading channels. Relying on the assumption of frequency selective Rayleigh fading channels we develop a closed form expression for the probability density function of the sum of the square channel coefficients at the output of maximum ratio combining (MRC) receivers. This allows for the formulation of the channel outage probability directly in terms of the channel energy and thus enables the analytic derivation of the outage probability in multi-user CDMA systems. Moreover, low complexity lower and upper bounds are derived, which provide the means for a well fitting approximation of the exact result directly through the cumulative distribution of the channel energy as obtained at the MRC output
{"title":"On the channel outage probability of multi-user CDMA systems","authors":"B. Zerlin, J. Brehmer, J. Nossek","doi":"10.1109/PIMRC.2005.1651696","DOIUrl":"https://doi.org/10.1109/PIMRC.2005.1651696","url":null,"abstract":"Like numerous other applications, novel cross-layer optimization schemes require the determination of the outage probability of fading channels. Relying on the assumption of frequency selective Rayleigh fading channels we develop a closed form expression for the probability density function of the sum of the square channel coefficients at the output of maximum ratio combining (MRC) receivers. This allows for the formulation of the channel outage probability directly in terms of the channel energy and thus enables the analytic derivation of the outage probability in multi-user CDMA systems. Moreover, low complexity lower and upper bounds are derived, which provide the means for a well fitting approximation of the exact result directly through the cumulative distribution of the channel energy as obtained at the MRC output","PeriodicalId":248766,"journal":{"name":"2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127774952","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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