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On the Ergodic Capacity Region of the Separately Correlated Rician Fading Multiple Access MIMO Channel 分离相关衰落多址MIMO信道遍历容量区域研究
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.295
Erwin Riegler, G. Taricco
{"title":"On the Ergodic Capacity Region of the Separately Correlated Rician Fading Multiple Access MIMO Channel","authors":"Erwin Riegler, G. Taricco","doi":"10.1109/GLOCOM.2007.295","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.295","url":null,"abstract":"The ergodic capacity region of a multiple access separately-correlated Rician fading MIMO channel is investigated by using an asymptotic approach. It is assumed that the number of transmit and receive antennas grow asymptotically approaching finite values while the number of users and the SNR are kept finite. It is shown by numerical results that this asymptotic approach is very accurate even when the number of antennas is as low as a few units. The ergodic capacity achieving covariance matrices for all users are derived according to the algorithm provided and the corresponding capacity is compared with the mutual information achieved by iid power allocation. Monte-Carlo simulations are also reported in order to verify the accuracy of the asymptotic results.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127502368","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}
引用次数: 10
Enhancing QoS Support in IEEE 802.11e HCCA 增强IEEE 802.11e HCCA对QoS的支持
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.931
Qinglin Zhao, D. Tsang
{"title":"Enhancing QoS Support in IEEE 802.11e HCCA","authors":"Qinglin Zhao, D. Tsang","doi":"10.1109/GLOCOM.2007.931","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.931","url":null,"abstract":"IEEE 802.11e standard develops a reference design to support the contention-free access. In the reference design, the packet transmission opportunity (TXOP) duration is calculated based on the mean data rate and the mean packet size, whereas the scheduled service interval (SI) is calculated based on the most stringent delay requirement. Such design can not effectively utilize the bandwidth and support the guaranteed packet loss requirement. This paper proposes a packet-loss-based and bandwidth-utilization-based (PB-based) design to address the two problems. In the PB-based design, the TXOP is calculated based on the data rate and packet size fluctuation, whereas the SI is calculated based on different delay requirements. In addition, when packet loss requirement is not taken into account, we propose an equal-spacing-based (ES-based) design to improve the bandwidth utilization. The proposed designs are helpful to provide more comprehensive QoS support.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125832527","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}
引用次数: 9
EXIT Chart Analysis of an Iterative Receiver with Channel Estimation 信道估计的迭代接收机出口图分析
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.762
D. P. Shepherd, Zhenning Shi, M. Anderson, M. Reed
{"title":"EXIT Chart Analysis of an Iterative Receiver with Channel Estimation","authors":"D. P. Shepherd, Zhenning Shi, M. Anderson, M. Reed","doi":"10.1109/GLOCOM.2007.762","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.762","url":null,"abstract":"In this paper we derive a novel extrinsic information transfer (EXIT) function for a channel estimator that uses both pilot symbols and soft decoding information. We consider a CDMA system with forward error correction that employs iterative multiuser detection based on soft interference cancellation and single user decoding. The J function is useful in convergence analysis as it provides a mapping between mutual information and variance. J functions are derived for both the flat-fading Rayleigh channel and channel estimate, allowing the a priori inputs to the channel estimator, interference canceller and decoder to be modeled. Algorithms for obtaining the EXIT functions for the three receiver blocks are proposed. We then combine the EXIT functions to create an EXIT chart that can be used to predict the behaviour of the overall receiver. Simulations are run for a 3GPP-like receiver in a mobile environment with a vehicle speed of 100 km/h. It is found that under these conditions, the detector trajectory closely matches our proposed EXIT chart.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126141523","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}
引用次数: 22
A Performance Study of IP and MPLS Traffic Engineering Techniques Under Traffic Variations 流量变化下IP和MPLS流量工程技术的性能研究
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.522
S. Dasgupta, J. D. Oliveira, J. Vasseur
{"title":"A Performance Study of IP and MPLS Traffic Engineering Techniques Under Traffic Variations","authors":"S. Dasgupta, J. D. Oliveira, J. Vasseur","doi":"10.1109/GLOCOM.2007.522","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.522","url":null,"abstract":"In this paper, a quantitative study of the benefits and shortcomings of IP and MPLS traffic engineering techniques under realistic traffic variation scenarios is presented. While both techniques can achieve similar degree of optimization under steady state conditions, our simulation results show the impact on each when realistic traffic variations are induced in the network. A detailed simulator has been developed to facilitate the study, and several new metrics of interest are analyzed to present a novel point of view.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126168457","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}
引用次数: 4
On Sphere Detection and Minimum-Phase Prefiltered Reduced-State Sequence Estimation 球面检测与最小相位预滤波约态序列估计
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.806
Morten Hansen, O. Winther, Lars P. B. Christensen
{"title":"On Sphere Detection and Minimum-Phase Prefiltered Reduced-State Sequence Estimation","authors":"Morten Hansen, O. Winther, Lars P. B. Christensen","doi":"10.1109/GLOCOM.2007.806","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.806","url":null,"abstract":"In this paper, prefiltering techniques for sphere detection (SD) in frequency-selective channels are examined. It is shown that a link between QL-factorization of the channel matrix and minimum-phase prefiltering exists. As a result, it is possible to regard SD as a generalization of traditional reduced- state sequence estimation, providing a unifying framework for the two detection methods. It is illustrated how minimum-phase prefiltering or the linear minimum mean-square error decision feedback equalization (LMMSE-DFE) forward filter is capable of reducing the complexity of sphere detectors significantly, while still obtaining near-optimal performance. The significant reduction in complexity is obtained as prefiltering enables earlier decision making in SD. Simulations carried out in an EDGE system confirm that prefiltering leads to a considerable complexity reduction for sphere detectors.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123213401","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}
引用次数: 3
Normalization of Linear Vector Channels 线性向量通道的归一化
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.862
A. Kotelba, A. Mämmelä, Desmond P. Taylor
{"title":"Normalization of Linear Vector Channels","authors":"A. Kotelba, A. Mämmelä, Desmond P. Taylor","doi":"10.1109/GLOCOM.2007.862","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.862","url":null,"abstract":"In this paper we study the normalization of mathematical models of linear vector channels. The ratio of the received energy to the transmitted energy is the energy gain of the channel. All physical systems follow an energy conservation law which implies that the energy gain of the channel is less than or equal to one. The major approaches for normalization include setting of either the average energy gain or the peak energy gain to unity. The peak energy gain of many mathematical fading models is infinite and those models cannot be normalized by the peak energy gain. We propose a new approach to normalization where the mathematical channel model is guaranteed to represent a physical system with a predefined probability. We show that the proper normalization of the mathematical model and the selection of the correct performance measure are of paramount importance in comparative performance analysis of adaptive transmission systems.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"191 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123277891","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}
引用次数: 4
Intelligent Estimation of Gateways Count for Reduced Data Latency in Wireless Sensor Networks 减少无线传感器网络数据延迟的网关数智能估计
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.174
W. Youssef, M. Younis
{"title":"Intelligent Estimation of Gateways Count for Reduced Data Latency in Wireless Sensor Networks","authors":"W. Youssef, M. Younis","doi":"10.1109/GLOCOM.2007.174","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.174","url":null,"abstract":"Wireless sensor networks (WSNs) have recently gained increased attention due to their potential use in numerous civil and military applications. In many of these applications, resource-constrained sensors are deployed to probe their surroundings and report their findings to one or multiple gateway nodes. In large networks, many sensors get involved in data relaying making the data latency unacceptably high. Since the number of deployed gateways and their locations impact the operation of the network, one of the option for reducing the data collection delay is to employ many gateways and appropriately place them in close proximity to data sources. However, increasing the gateway count imposes high cost for the additional hardware resources and their deployment means, thus a tradeoff would be unavoidable. In this paper, we introduce a novel approach for estimating the least number of gateways required for meeting some upper bound on data latency. In addition, we present a heuristic for finding best locations for these gateways. Validation results confirm the effectiveness of the proposed approach.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125335139","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}
引用次数: 9
Iterative Decoding of Concatenated Channel Coding and Trellis Shaping Based on Markov Model 基于马尔可夫模型的串联信道编码迭代译码及栅格整形
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.742
M. Tanahashi, H. Ochiai
{"title":"Iterative Decoding of Concatenated Channel Coding and Trellis Shaping Based on Markov Model","authors":"M. Tanahashi, H. Ochiai","doi":"10.1109/GLOCOM.2007.742","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.742","url":null,"abstract":"The trellis shaping (TS) is an effective technique not only for average power reduction of high-order QAM signals, but also for peak power reduction of band-limited single-carrier PSK signals. Our recent work has demonstrated that signals with almost constant envelope can be generated. Compared to the unshaped PSK system, however, this shaping process introduces signal constellation expansion exclusively for peak power reduction and thus reduces the minimum Euclidean distance of the PSK signal constellation, rendering the overall system sensitive to channel noise. To overcome this drawback, this paper proposes a new decoding algorithm of the TS that exploits the Markov process property of the shaped symbols. This decoding algorithm can work alone, but becomes more effective when the shaping encoder is serially concatenated with a channel coding. The simulation results demonstrate that this serial concatenation together with an iterative decoding between shaping and coding can achieve a significant amount of coding gain.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125346870","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}
引用次数: 2
Cognitive Radio Networks: How Much Spectrum Sharing is Optimal? 认知无线电网络:多少频谱共享是最优的?
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.596
Sudhir Srinivasa, S. Jafar
{"title":"Cognitive Radio Networks: How Much Spectrum Sharing is Optimal?","authors":"Sudhir Srinivasa, S. Jafar","doi":"10.1109/GLOCOM.2007.596","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.596","url":null,"abstract":"We explore the performance tradeoff between opportunistic and regulated access inherent in the design of multiuser cognitive radio networks. We consider a cognitive radio system with sensing limits at the secondary users and interference tolerance limits at the primary and secondary users. Our objective is to determine the optimal amount of spectrum sharing, i.e., the number of secondary users that maximizes the total deliverable throughput in the system. We begin with the case of perfect primary user detection and zero interference tolerance at each of the primary and secondary nodes. We find that the optimal fraction of licensed users lies between the two extremes of fully opportunistic and fully licensed operation and is equal to the traffic duty cycle. For the more involved case of imperfect sensing and non-zero interference tolerance constraints, we provide numerical simulation results to study the tradeoff between licensing and autonomy and the impact of primary user sensing and interference tolerance on the deliverable throughput.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125545499","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}
引用次数: 41
Combined SINR Based Vertical Handoff Algorithm for Next Generation Heterogeneous Wireless Networks 基于联合SINR的下一代异构无线网络垂直切换算法
IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference Pub Date : 2007-12-26 DOI: 10.1109/GLOCOM.2007.852
Kemeng Yang, I. Gondal, B. Qiu, L. Dooley
{"title":"Combined SINR Based Vertical Handoff Algorithm for Next Generation Heterogeneous Wireless Networks","authors":"Kemeng Yang, I. Gondal, B. Qiu, L. Dooley","doi":"10.1109/GLOCOM.2007.852","DOIUrl":"https://doi.org/10.1109/GLOCOM.2007.852","url":null,"abstract":"Next generation heterogeneous wireless networks offer the end users with assurance of QoS inside each access network as well as during vertical handoff between them. For guaranteed QoS, the vertical handoff algorithm must be QoS aware, which cannot be achieved with the use of traditional RSS as the vertical handoff criteria. In this paper, we propose a novel vertical handoff algorithm which uses received SINR from various access networks as the handoff criteria. This algorithm consider the combined effects of SINR from different access networks with SINR value from one network being converted to equivalent SINR value to the target network, so the handoff algorithm can have the knowledge of achievable bandwidths from both access networks to make handoff decisions with QoS consideration. Analytical results confirm that the new SINR based vertical handoff algorithm can consistently offer the end user with maximum available bandwidth during vertical handoff contrary to the RSS based vertical handoff, whose performance differs under different network conditions. System level simulations also reveal the improvement of overall system throughputs using SINR based vertical handoff, comparing with the RSS based vertical handoff.","PeriodicalId":370937,"journal":{"name":"IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126660992","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}
引用次数: 179
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