Pub Date : 2008-03-05DOI: 10.1109/RWS.2008.4463518
S. Bensmida, O. Hammi, F. Ghannouchi
In this paper, a high efficiency GaN based power amplifier is designed using multi-harmonics load pull measurements. A load matching network that independently controls the load impedance at the fundamental, second and third harmonic frequencies is used for straightforward implementation. The continuously driven single-ended deep class AB biased power amplifier achieves a peak power added efficiency of 68% at saturation. It is found that the designed power amplifier exhibit highly non linear characteristics with 7 dB gain compression at saturation. Digital predistortion based linearizer is used to improve the linearity performance of the power amplifier under a WCDMA excitation (PAPR=9.8 dB). At a 10 dB output power back-off, 21% power added efficiency was measured along with 53 dBc adjacent channel leakage ratio.
{"title":"High efficiency digitally linearized GaN based power amplifier for 3G applications","authors":"S. Bensmida, O. Hammi, F. Ghannouchi","doi":"10.1109/RWS.2008.4463518","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463518","url":null,"abstract":"In this paper, a high efficiency GaN based power amplifier is designed using multi-harmonics load pull measurements. A load matching network that independently controls the load impedance at the fundamental, second and third harmonic frequencies is used for straightforward implementation. The continuously driven single-ended deep class AB biased power amplifier achieves a peak power added efficiency of 68% at saturation. It is found that the designed power amplifier exhibit highly non linear characteristics with 7 dB gain compression at saturation. Digital predistortion based linearizer is used to improve the linearity performance of the power amplifier under a WCDMA excitation (PAPR=9.8 dB). At a 10 dB output power back-off, 21% power added efficiency was measured along with 53 dBc adjacent channel leakage ratio.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"163 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122504914","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463624
C. Cook
This article illustrates the performance benefits to a cellular network of the introduction and integration of an underlain relay network. These relay elements are designed to operate in the service providers' licensed spectrum and provide a significant load balancing function between cells while increasing coverage restricted by shadowing and building penetration. The analysis is based on a mobile traffic simulation program developed by the author, which characterizes call blocking, call drops, handoffs and overhead messaging loads. The underlying relay elements are wirelessly integrated into the network. Both the underlying relay network and the Macro network are modeled with a number of dedicated voice channels. The number of voice channels allocated for each cell and relay is kept constant across the simulated, 19 cell, cluster and these allocations are varied between simulation runs for the design analysis curves.
{"title":"Performance simulation of a wireless relay network","authors":"C. Cook","doi":"10.1109/RWS.2008.4463624","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463624","url":null,"abstract":"This article illustrates the performance benefits to a cellular network of the introduction and integration of an underlain relay network. These relay elements are designed to operate in the service providers' licensed spectrum and provide a significant load balancing function between cells while increasing coverage restricted by shadowing and building penetration. The analysis is based on a mobile traffic simulation program developed by the author, which characterizes call blocking, call drops, handoffs and overhead messaging loads. The underlying relay elements are wirelessly integrated into the network. Both the underlying relay network and the Macro network are modeled with a number of dedicated voice channels. The number of voice channels allocated for each cell and relay is kept constant across the simulated, 19 cell, cluster and these allocations are varied between simulation runs for the design analysis curves.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128097348","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463479
T. Dey, S.K. Mondal, M. Hashem
To effectively support the communication in such a dynamic networking environment as the ad hoc networks, the routing protocol has to be adaptable to the spatial and temporal changes in the characteristics of the network, such as traffic and mobility patterns. In this paper, we propose and analyze a routing protocol called Adaptive Monitor Based Routing (AMBR) that discovers and maintains routes in hierarchical and distributed fashion and locally repairs the broken link. The main motivation behind the proposed AMBR is to drastically cut down flooding, to substantially tame the routing overhead, to repair broken link locally in order to minimize the routing overhead and to increase efficiencies in packet movement in the ad hoc networks. An analytical model for the AMBR technique is presented. Simulation results illustrate its performance and demonstrate its good behavior comparing with other prevalent protocols. The proposed protocol achieved substantial improvement in terms of flooding, routing overhead and network overhead and hence, provides enhanced reliability.
{"title":"Performance enhancement of ad hoc networks with adaptive monitor based routing","authors":"T. Dey, S.K. Mondal, M. Hashem","doi":"10.1109/RWS.2008.4463479","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463479","url":null,"abstract":"To effectively support the communication in such a dynamic networking environment as the ad hoc networks, the routing protocol has to be adaptable to the spatial and temporal changes in the characteristics of the network, such as traffic and mobility patterns. In this paper, we propose and analyze a routing protocol called Adaptive Monitor Based Routing (AMBR) that discovers and maintains routes in hierarchical and distributed fashion and locally repairs the broken link. The main motivation behind the proposed AMBR is to drastically cut down flooding, to substantially tame the routing overhead, to repair broken link locally in order to minimize the routing overhead and to increase efficiencies in packet movement in the ad hoc networks. An analytical model for the AMBR technique is presented. Simulation results illustrate its performance and demonstrate its good behavior comparing with other prevalent protocols. The proposed protocol achieved substantial improvement in terms of flooding, routing overhead and network overhead and hence, provides enhanced reliability.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132809326","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463605
M. Angermann, W. Truszkowski
This paper discusses the role of communication and localization as enabling technologies of swarm-intelligent systems. In this work swarm-intelligence is understood as an evolving capability of decentralized, self-organized systems whose elements are collectively able to coordinate and synchronize their actions towards fulfilling a common goal. In order to share their observations of the environment, processing results or internal states, a swarm's elements form a dynamic communication network. Additionally, the swarm elements form a second network, consisting of measurements for determining their relative positions. The paper discusses the fundamental differences between these two networks and illustrates the applicability of the swarm-intelligence perspective in several application fields.
{"title":"Communication and localization networks in swarm-intelligent systems","authors":"M. Angermann, W. Truszkowski","doi":"10.1109/RWS.2008.4463605","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463605","url":null,"abstract":"This paper discusses the role of communication and localization as enabling technologies of swarm-intelligent systems. In this work swarm-intelligence is understood as an evolving capability of decentralized, self-organized systems whose elements are collectively able to coordinate and synchronize their actions towards fulfilling a common goal. In order to share their observations of the environment, processing results or internal states, a swarm's elements form a dynamic communication network. Additionally, the swarm elements form a second network, consisting of measurements for determining their relative positions. The paper discusses the fundamental differences between these two networks and illustrates the applicability of the swarm-intelligence perspective in several application fields.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131996477","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463535
J. Schwartz, J. Azaña, D. Plant
We describe a fully-electronic system for compressing and/or reversing arbitrarily-shaped waveforms in the time-domain using the principles of temporal imaging. The system accepts a arbitrary time-windowed broadband input and outputs a chirped waveform with the same envelope but compressed and/or reversed in time. We present a demonstration of a 3X time-compression and a basic time-reversal on a simple waveform and discuss the challenges and limitations of the proposed technique.
{"title":"An electronic temporal imaging system for compression and reversal of arbitrary UWB waveforms","authors":"J. Schwartz, J. Azaña, D. Plant","doi":"10.1109/RWS.2008.4463535","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463535","url":null,"abstract":"We describe a fully-electronic system for compressing and/or reversing arbitrarily-shaped waveforms in the time-domain using the principles of temporal imaging. The system accepts a arbitrary time-windowed broadband input and outputs a chirped waveform with the same envelope but compressed and/or reversed in time. We present a demonstration of a 3X time-compression and a basic time-reversal on a simple waveform and discuss the challenges and limitations of the proposed technique.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134354105","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463513
Jin-Fa Chang, Yo‐Sheng Lin, Chi-Chen Chen, Chang‐Zhi Chen, Tao Wang, Shey-Shi Lu
We demonstrate that miniature millimeter-wave (MMW) band-pass filter can be obtained by replacing the traditional eoplanar waveguide structures with the miniature lumped-spiral inductors and metal-insulator-metal (MIM) capacitors. To study the substrate effects on the performances of the spiral inductor and filter, CMOS-compatible backside inductively-coupled-plasma (ICP) deep trench technology was used to selectively remove the silicon underneath them. The results show that a 70.9% (from 5.8 to 9.91) and a 298.7% (from 2.33 to 9.29) increase in Q-factor were achieved at 40 GHz and 60 GHz, respectively, for a 251.7 pH inductor after the ICP etching. In addition, a 0.9 dB (from -5.4 dB to -4.6 dB) improvement in peak insertion loss (S23) was achieved for the miniature bandpass filter with 3-dB bandwidth of 47.7 GHz (18.4 ~ 66.1 GHz) after the ICP etching. The chip area of the miniature filter was only 206 mum x 106 mum excluding the test pads.
{"title":"A miniature micro-machined millimeter-wave bandpass filter by CMOS compatible ICP deep-trench technology","authors":"Jin-Fa Chang, Yo‐Sheng Lin, Chi-Chen Chen, Chang‐Zhi Chen, Tao Wang, Shey-Shi Lu","doi":"10.1109/RWS.2008.4463513","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463513","url":null,"abstract":"We demonstrate that miniature millimeter-wave (MMW) band-pass filter can be obtained by replacing the traditional eoplanar waveguide structures with the miniature lumped-spiral inductors and metal-insulator-metal (MIM) capacitors. To study the substrate effects on the performances of the spiral inductor and filter, CMOS-compatible backside inductively-coupled-plasma (ICP) deep trench technology was used to selectively remove the silicon underneath them. The results show that a 70.9% (from 5.8 to 9.91) and a 298.7% (from 2.33 to 9.29) increase in Q-factor were achieved at 40 GHz and 60 GHz, respectively, for a 251.7 pH inductor after the ICP etching. In addition, a 0.9 dB (from -5.4 dB to -4.6 dB) improvement in peak insertion loss (S23) was achieved for the miniature bandpass filter with 3-dB bandwidth of 47.7 GHz (18.4 ~ 66.1 GHz) after the ICP etching. The chip area of the miniature filter was only 206 mum x 106 mum excluding the test pads.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134623692","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463537
D. Trinchero, A. Galardinr, R. Stefanelli, E. Guariso, F. Cambiotti, F. Troisr, L. Baldaccr, D. Della Monica, E. Ragno, R. Moriondo, M. Ancillr, S. Schiavr
The paper describes the results obtained from a research activity aimed to realise very-low-cost wireless transmitters for the realisation of high capacity point-to-point radio-links over huge distances. The transmitters were obtained from recycled PC hardware components and low- cost radio boards for IEEE 802.11a and IEEE 802.11 h applications. The manufactured hardware was used to implement a topology network made of links ranging from 100 to 300 kms. Performance analyses were run for about six months, showing extraordinary stability and reliability and excellent data transport performance..
{"title":"An independent, low cost and open source solution for the realisation of wireless links over huge multikilometric distance","authors":"D. Trinchero, A. Galardinr, R. Stefanelli, E. Guariso, F. Cambiotti, F. Troisr, L. Baldaccr, D. Della Monica, E. Ragno, R. Moriondo, M. Ancillr, S. Schiavr","doi":"10.1109/RWS.2008.4463537","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463537","url":null,"abstract":"The paper describes the results obtained from a research activity aimed to realise very-low-cost wireless transmitters for the realisation of high capacity point-to-point radio-links over huge distances. The transmitters were obtained from recycled PC hardware components and low- cost radio boards for IEEE 802.11a and IEEE 802.11 h applications. The manufactured hardware was used to implement a topology network made of links ranging from 100 to 300 kms. Performance analyses were run for about six months, showing extraordinary stability and reliability and excellent data transport performance..","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133735437","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463612
N. Sasaki, M. Fukuda, K. Kimoto, T. Kikkawa
Ultra-wideband (UWB) transmitter and receiver circuits were developed and inter-chip wireless communication with silicon integrated antennas using Gaussian monocycle pulse (GMP) was performed. Inter-chip data transmissions for stacked Si LS's having GMP transmitter circuits by use of 0.18 mum CMOS technology were performed. Differential Gaussian monocycle pulses with data rates of 200 Mbps were generated. On-off-keying (OOK) modulation scheme was adopted for data transmission. Synchronous GMP receiver having double GMP generators was developed. Clock timing and OOK data pulses were alternately sent using on-chip transmitting antenna. 200 Mbps data recovery was achieved at the distance of 0.5 mm.
研制了超宽带(UWB)收发电路，实现了基于高斯单环脉冲(GMP)的硅集成天线芯片间无线通信。采用0.18 μ m CMOS技术实现了具有GMP发射电路的堆叠Si LS的片间数据传输。产生数据速率为200mbps的高斯差分单环脉冲。数据传输采用开-关键(OOK)调制方式。研制了双GMP发生器同步GMP接收器。时钟定时和OOK数据脉冲通过片上发射天线交替发送。在0.5 mm的距离上实现了200mbps的数据恢复。
{"title":"CMOS UWB transmitter and receiver with silicon integrated antennas for inter-chip wireless interconnection","authors":"N. Sasaki, M. Fukuda, K. Kimoto, T. Kikkawa","doi":"10.1109/RWS.2008.4463612","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463612","url":null,"abstract":"Ultra-wideband (UWB) transmitter and receiver circuits were developed and inter-chip wireless communication with silicon integrated antennas using Gaussian monocycle pulse (GMP) was performed. Inter-chip data transmissions for stacked Si LS's having GMP transmitter circuits by use of 0.18 mum CMOS technology were performed. Differential Gaussian monocycle pulses with data rates of 200 Mbps were generated. On-off-keying (OOK) modulation scheme was adopted for data transmission. Synchronous GMP receiver having double GMP generators was developed. Clock timing and OOK data pulses were alternately sent using on-chip transmitting antenna. 200 Mbps data recovery was achieved at the distance of 0.5 mm.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132683047","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 : 2008-03-05DOI: 10.1049/iet-cds.2008.0362
V. Rajagopal, S. Islam, M. Haider, L. Zuo
We describe a divide-by-4 injection-locked frequency divider (ILFD) based on a novel process and temperature compensation technique. The ILFD possesses a wide locking range over process corners and a wide temperature range due to the proposed compensation technique. The core of the ILFD consists of ring oscillator based on a modified version of symmetric load (Maneatis) delay elements. A calibration circuitry can be used to further enhance the locking range. Measurement results show that the proposed ILFD functions as a divide-by-4 circuit for an input frequency range from 1.8 GHz to 3.2 GHz for a power level as low as -3 dBm. The worst-case power consumption was approx. 2 mW from a 1.8 V power supply. The proposed ILFD can be used as a low-power prescaler for multi-band applications.
{"title":"A wideband Injection Locked Frequency Divider based on a process and temperature compensated ring oscillator","authors":"V. Rajagopal, S. Islam, M. Haider, L. Zuo","doi":"10.1049/iet-cds.2008.0362","DOIUrl":"https://doi.org/10.1049/iet-cds.2008.0362","url":null,"abstract":"We describe a divide-by-4 injection-locked frequency divider (ILFD) based on a novel process and temperature compensation technique. The ILFD possesses a wide locking range over process corners and a wide temperature range due to the proposed compensation technique. The core of the ILFD consists of ring oscillator based on a modified version of symmetric load (Maneatis) delay elements. A calibration circuitry can be used to further enhance the locking range. Measurement results show that the proposed ILFD functions as a divide-by-4 circuit for an input frequency range from 1.8 GHz to 3.2 GHz for a power level as low as -3 dBm. The worst-case power consumption was approx. 2 mW from a 1.8 V power supply. The proposed ILFD can be used as a low-power prescaler for multi-band applications.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123979894","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 : 2008-03-05DOI: 10.1109/RWS.2008.4463554
J. Kountouriotis, D. Piazza, P. Mookiah, M. d'Amico, K. Dandekar
In this paper we investigate the performance of reconflgurable antennas in an MIMO ad-hoc network. The nodes employ the multiuser waterfllling (known also as iterative waterfllling) power allocation [1], [2] method and we use network sum capacity as a performance metric. We study a centralized configuration selection scheme, which can be used as an upper bound in the sum capacity using reconflgurable antennas, as well as a simple distributed configuration selection scheme, suitable for use in an ad-hoc MIMO network.
{"title":"Reconfigurable antennas for MIMO ad-hoc networks","authors":"J. Kountouriotis, D. Piazza, P. Mookiah, M. d'Amico, K. Dandekar","doi":"10.1109/RWS.2008.4463554","DOIUrl":"https://doi.org/10.1109/RWS.2008.4463554","url":null,"abstract":"In this paper we investigate the performance of reconflgurable antennas in an MIMO ad-hoc network. The nodes employ the multiuser waterfllling (known also as iterative waterfllling) power allocation [1], [2] method and we use network sum capacity as a performance metric. We study a centralized configuration selection scheme, which can be used as an upper bound in the sum capacity using reconflgurable antennas, as well as a simple distributed configuration selection scheme, suitable for use in an ad-hoc MIMO network.","PeriodicalId":431471,"journal":{"name":"2008 IEEE Radio and Wireless Symposium","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121572779","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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