2009 6th International Symposium on Wireless Communication Systems最新文献_第6页

A user-centric mobility framework for multimedia interactive applications 一个以用户为中心的移动框架，用于多媒体交互应用程序

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285365

R. Bolla, R. Rapuzzi, M. Repetto

引用次数: 7

A channel allocation algorithm for OSA-enabled IEEE 802.11 WLANs 用于支持osa的IEEE 802.11 wlan的信道分配算法

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285281

Francisco Novillo, M. Churchman, R. Ferrús, R. Agustí

{"title":"A channel allocation algorithm for OSA-enabled IEEE 802.11 WLANs","authors":"Francisco Novillo, M. Churchman, R. Ferrús, R. Agustí","doi":"10.1109/ISWCS.2009.5285281","DOIUrl":"https://doi.org/10.1109/ISWCS.2009.5285281","url":null,"abstract":"Channel allocation problem is a major challenge in wireless local area networks (WLANs), especially in dense deployments of access points (APs) where congestion of the unlicensed spectrum bands (i.e., ISM bands) could undermine achieved network performance. This paper analyses the possibility to alleviate congestion of the ISM band by allowing some APs to use additional channels located in licensed bands in an opportunistic manner whenever licensee services (i.e., primary users) are not affected. Availability of these additional channels in licensed bands is assumed not to be the same for all the APs. Based on this assumption, we formulate the problem for the channel assignment as a Binary Linear Programming (BLP) problem, which allows us to obtain an optimal solution despite an elevated execution time. We also develop a heuristic method based on building a Minimum Spanning Tree (MST) graph attending to interference conditions that is able to find near-optimal solutions with a shorter execution time. Results are provided to assess the benefits of such a proposal under different WLAN deployment situations and primary channel availability conditions.","PeriodicalId":344018,"journal":{"name":"2009 6th International Symposium on Wireless Communication Systems","volume":"181 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125617924","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: 7

Multimedia session continuity with context-aware capability in IMS-based network ims网络中具有上下文感知能力的多媒体会话连续性

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285326

Nguyen Huu Thanh, Le Thi Thuy Hang, T. Quynh, V. V. Yem, Nguyen Xuan Dung

{"title":"Multimedia session continuity with context-aware capability in IMS-based network","authors":"Nguyen Huu Thanh, Le Thi Thuy Hang, T. Quynh, V. V. Yem, Nguyen Xuan Dung","doi":"10.1109/ISWCS.2009.5285326","DOIUrl":"https://doi.org/10.1109/ISWCS.2009.5285326","url":null,"abstract":"In this paper we firstly proved that Mobile IP protocols are designed for mobility but not for session continuity. In contradiction, mSCTP (mobile Stream Control Transmission Protocol) appears to be the best protocol with regard to session continuity support, however it does not support location management mechanisms, thus context-aware QoS as well as other mechanisms based on knowledge of location are hardly accommodated. On the other hand, the standardized IP Multimedia Subsystem (IMS) solution initially introduced by 3GPP adopts the policy-based QoS model to map user's subscription to a pre-defined QoS level, to apply service-based charging and to prevent Theft-of-Service. In this article we propose a new approach that integrates mSCTP into IMS networks to facilitate session continuity and to provide mechanisms for service control. It is realized by a proxy based on mSCTP (mobile Stream Control Transmission Protocol) that acts as an anchor point for soft vertical handover of mobile nodes, which have multiple physical interfaces (e.g., WLAN/UMTS). The mSCTP-based proxy also supports QoS provisioning and adaptation for the mobile nodes when moving in a heterogeneous wireless environment. Results show that the signaling cost for handover in our approach can be up to 23 times smaller than that in the conventional approach.","PeriodicalId":344018,"journal":{"name":"2009 6th International Symposium on Wireless Communication Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130080738","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: 12

Distributed Interleave-Division Multiplexing Space-Time Codes for coded relay networks 编码中继网络的分布式交错多路空时码

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285280

P. Weitkemper, D. Wübben, K. Kammeyer

{"title":"Distributed Interleave-Division Multiplexing Space-Time Codes for coded relay networks","authors":"P. Weitkemper, D. Wübben, K. Kammeyer","doi":"10.1109/ISWCS.2009.5285280","DOIUrl":"https://doi.org/10.1109/ISWCS.2009.5285280","url":null,"abstract":"In this paper the application of the recently proposed Interleave-Division Multiplexing Space-Time Codes (IDM-STC) in coded relay networks is investigated. IDM-STC are a very flexible scheme to exploit space diversity with the benefits of IDM such as robustness against asynchronism and efficient iterative detection. While IDM-STC have been investigated for MIMO systems, relay networks induce additional constraints like imperfect decoding at the relay and limited cooperation. Consequently, not only the choice of the diversity scheme, but also the applied relay functionality significantly influences the overall performance. In this paper different relay schemes in combination with IDM-STC are considered for coded relay networks. Amplify-Forward (AF) does not assume any signal processing at the relays and just forwards the received signal. Decode-Forward (DF) fully decodes the received signal which can lead to error propagation. Another relaying scheme called Estimate-Forward (EF), which combines the advantages of AF and DF, was recently extended to coded systems and is called Decode-Estimate-Forward (DEF). A coded IDM-STC relay system with different relay schemes is investigated to show the good performance of IDM-STC combined with DEF in realistic scenarios with small overhead and robustness against asynchronism.","PeriodicalId":344018,"journal":{"name":"2009 6th International Symposium on Wireless Communication Systems","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127771010","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

A study of cooperative communication with consideration of power loss caused by relay abortion 考虑中继流产功率损失的合作通信研究

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285276

Mayumi Suzuki, O. Takyu, Y. Umeda

引用次数: 1

Joint power management and beamforming for base stations in Cognitive Radio systems 认知无线电系统中基站的联合功率管理和波束形成

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285316

Xiao Fu, Jun Wang, Shaoqian Li

引用次数: 27

Optimized Orphan Algorithm for IEEE 802.15.4 networks IEEE 802.15.4网络的优化孤儿算法

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285294

A. García-Sánchez, F. García-Sánchez, J. García-Haro

引用次数: 2

Optimising transmission path selection in SCTP based wireless networking 基于SCTP的无线网络传输路径选择优化

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285311

Martin Hynes, L. Kilmartin

{"title":"Optimising transmission path selection in SCTP based wireless networking","authors":"Martin Hynes, L. Kilmartin","doi":"10.1109/ISWCS.2009.5285311","DOIUrl":"https://doi.org/10.1109/ISWCS.2009.5285311","url":null,"abstract":"A number of different protocols have been proposed to support the concept of wireless terminal mobility. One such protocol is SCTP which includes functionality to monitor the characteristics of the primary path and all alternate secondary paths connecting two hosts. This supports a basic mechanism by which traffic can be switched from a primary path to a secondary path in the case of a primary path failure. This paper focuses on further enhancing this functionality to support switching between the available paths in order to optimise the overall data throughput between the hosts. A number of alternate algorithms are proposed to control this mechanism and the performance of these algorithms has been evaluated in a simulated network environment. The results of these simulations show that they can offer a superior performance as quantified in terms of mean handover rates and handover latency compared to the current SCTP standard algorithm and a previously suggested solution. It is shown that the proposed algorithms results in a reduction in the mean handover rate to approximately 4% of the mean handover rate of existing suggested handover control algorithms.","PeriodicalId":344018,"journal":{"name":"2009 6th International Symposium on Wireless Communication Systems","volume":"254 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114275884","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: 1

Seed graph expansion for construction of structured LDPC codes 构造结构化LDPC码的种子图展开

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285248

W. Sułek

引用次数: 6

Evaluation of wireless channel quality for an ad hoc network in the sky, SKYMESH 天空自组织网络无线信道质量评价，skyymesh

2009 6th International Symposium on Wireless Communication Systems Pub Date : 2009-09-07 DOI: 10.1109/ISWCS.2009.5285366

Tomoaki Umeki, Hiraku Okada, K. Mase

{"title":"Evaluation of wireless channel quality for an ad hoc network in the sky, SKYMESH","authors":"Tomoaki Umeki, Hiraku Okada, K. Mase","doi":"10.1109/ISWCS.2009.5285366","DOIUrl":"https://doi.org/10.1109/ISWCS.2009.5285366","url":null,"abstract":"This paper investigates the statistical characteristics of the wireless channel in an ad hoc network in the sky “SKYMESH,” which is a solution for temporal communication networks in the large-scale natural disasters. SKYMESH consists of balloon nodes, which are located at 50–100 m high over the the ground, and build the wireless network in the air. In this system, line-of-sight (LoS) is kept between balloon nodes, and the disaster area can be covered effectively. Wireless channel quality is quickly changed due to the swinging of balloon nodes. In order to investigate the statistical characteristics of the wireless channel, receive signal strength indicator (RSSI) and swing strength of the balloon nodes is measured in the field experiment at Niigata University in August 2008, and at Yamakoshi, Nagaoka-city in October 2008. As a result, when the angle rate of communication equipments increases, the standard deviation of RSSI in the inter-balloon communications increases. In the communications between the balloon and the ground nodes, long-term statistics is caused by the change of the antenna direction by wind, and short-term statistics is Nakagami-Rice fading environment.","PeriodicalId":344018,"journal":{"name":"2009 6th International Symposium on Wireless Communication Systems","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123102941","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: 14