发布求助
文献互助 智能选刊 最新文献

1st International Symposium onWireless Communication Systems, 2004.最新文献

筛选
英文 中文
Supporting real-time applications with better QoS guarantees in 802.11 在802.11中支持具有更好QoS保证的实时应用
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407272
K. Diwakar, S. Iyer
{"title":"Supporting real-time applications with better QoS guarantees in 802.11","authors":"K. Diwakar, S. Iyer","doi":"10.1109/ISWCS.2004.1407272","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407272","url":null,"abstract":"The proliferation of IEEE 802.11 based wireless LANs has led to a lot of interest in providing quality of service(QoS) guarantees in such networks. 802.11e is the QoS variant of the 802.11 family of protocols. It suggests a flow-based solution based on priority queues at the node, for providing QoS guarantees. We propose a different approach, using a variant of TDMA, called dynamic time-division multiple access(DTMA). It is based on the observation that the ratio of data transmission time to control packet (poll or acknowledgement) transmission time is typically 6:1, and drops down almost to 2:1 when the data packet size becomes smaller than 600 bytes. DTMA focusses on reducing control information and thereby increasing time available for data transmission. More time available for data transmission implies increased throughput. We expunge the overhead of control packets in HCF by using cumulative acknowledgements and piggybacking. Taking advantage of 802.11's inherent limited range, DTMA, a modified TDMA is used for data transfer in HCF, without encountering the problem of distributed time synchronization. In this paper, we do the analysis of 802.11e and DTMA using probability models and also present simulation results to support these models. Thus, aided by simulations and analytical methods, we prove that DTMA has stricter and lesser delay bounds than 802.11e, for real-time and QoS sensitive applications. We also show that DTMA enhances the overall throughput by almost 20%, thereby implying better QoS guarantees in the 802.11 domain.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128608555","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
Analog MIMO detector: the concept and initial results 模拟MIMO检测器:概念和初步结果
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407253
R. Piechocki, J. Garrido, D. McNamara, Joe McGeehan, A. Nix
{"title":"Analog MIMO detector: the concept and initial results","authors":"R. Piechocki, J. Garrido, D. McNamara, Joe McGeehan, A. Nix","doi":"10.1109/ISWCS.2004.1407253","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407253","url":null,"abstract":"In this contribution we propose an analogue receiver that can perform turbo detection in MIMO systems. The receiver is built from discrete non-linear analogue devices that perform detection in a \"free-flow\" network (no notion of iterations). This contribution can be viewed as an extension of analogue turbo decoder concepts to include MIMO detection. These first analogue implementations report reductions of few orders of magnitude in the number of required transistors, consumed energy and the same order of improvement in processing speed. Our implementation of MIMO decoder brings about the same advantages, when compared to traditional (DSP/FPGA) implementations.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130130621","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
An advanced multi-element microcellular ray tracing model 一种先进的多元素微细胞射线追踪模型
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407285
K. H. Ng, E. Tameh, A. Nix
{"title":"An advanced multi-element microcellular ray tracing model","authors":"K. H. Ng, E. Tameh, A. Nix","doi":"10.1109/ISWCS.2004.1407285","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407285","url":null,"abstract":"In this paper an advanced site specific image-based ray-tracing model is developed that enables multi-element outdoor propagation analysis to be performed in a microcellular environment. Sophisticated optimization techniques such as pre-processing the environment database using object partitioning, visibility determination, diffraction image tree pre-calculation techniques, and parallel processing are used to improve run time efficiency. A comparison of path loss prediction with multi-element site specific measurements shows strong agreement, with a mean error of 3.6 dB and a standard deviation of 3.2 dB. The model is also shown to be capable of performing detailed MIMO analysis.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"96 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130960185","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: 16
Evolutionary cell planner 进化细胞规划器
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407213
Yee Hui Lee, P. Chong
{"title":"Evolutionary cell planner","authors":"Yee Hui Lee, P. Chong","doi":"10.1109/ISWCS.2004.1407213","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407213","url":null,"abstract":"Much work has been done on the use of heuristic techniques for the optimization and planning of mobile networks [Xuemin Huang et al., 2000]-[Xuemin Huang, 2001]. Monte Carlo, genetic algorithm (GA) [D.E. Goldberg, 1989] and simulated annealing (SA) have been used for the purpose of cell planning with moderate success. In this paper, a proposed evolutionary learning technique [Y.H. Lee et al., 2004] is used for the optimization and cell planning. This technique is able to perform a heuristic search with intelligence; knowledge gained from information gathered from previously searched problem space. The success of this technique is attributed to its ability to evolve the cell planning design in an intelligent way with knowledge of the previously searched cell plans. In this paper, a simple example, with Singapore as the model, is used to illustrate the capability of the evolutionary cell planner.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"460 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122994318","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
Multi-standard simulation of WLAN/UMTS/GSM transceivers for analog front-end validation and design 多标准仿真WLAN/UMTS/GSM收发器的模拟前端验证与设计
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407200
S. Vitali, N. D. Laurentiis, G. Albertazzi, Federico Agnelli, R. Rovatti
{"title":"Multi-standard simulation of WLAN/UMTS/GSM transceivers for analog front-end validation and design","authors":"S. Vitali, N. D. Laurentiis, G. Albertazzi, Federico Agnelli, R. Rovatti","doi":"10.1109/ISWCS.2004.1407200","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407200","url":null,"abstract":"A system-level multi-standard simulator is set up to help the architectural and circuit-level design of RF front-ends whose building blocks are meant to be shared between transceiver chains of different standards. The simulator distinguishes the baseband digital processing and analog processing. Non idealities of analog blocks are modeled in detail taking into account the nonlinearities, band limitation, losses, thermal noise, etc. The simulator provides all classical compliance tests (sensitivity, maximum input, adjacent channel rejection, pureness of modulation, spectral profile, etc.) and can also assess the joint effect of high-level analog design parameters on the performance of the transmission chain at bit- or packet- level.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"PP 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126404021","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: 6
An enhanced Reed-Solomon decoder for wireless communication systems 一种用于无线通信系统的增强型里德-所罗门解码器
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407237
S. Egorov, G. Markarian
{"title":"An enhanced Reed-Solomon decoder for wireless communication systems","authors":"S. Egorov, G. Markarian","doi":"10.1109/ISWCS.2004.1407237","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407237","url":null,"abstract":"The Reed-Solomon decoder based on the modified Blahut procedure is proposed. This decoder provides error correction beyond half the minimum code distance. An architecture of a searcher for unknown discrepancies is given. This architecture allows the implementation complexity of the decoder to be decreased considerably. The coding gain and implementation complexity of the proposed decoder are shown.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126031578","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: 0
Speed effect on the link level performance of a multi node B enhanced UTRAN architecture 速度对多节点B增强型UTRAN架构链路级性能的影响
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407201
D. Argiles, Ó. Lázaro, L. Rubio, N. Cardona, G. Piñero
{"title":"Speed effect on the link level performance of a multi node B enhanced UTRAN architecture","authors":"D. Argiles, Ó. Lázaro, L. Rubio, N. Cardona, G. Piñero","doi":"10.1109/ISWCS.2004.1407201","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407201","url":null,"abstract":"Future mobile communication requires not only increased bit rates but also flexible architectures, which could put the required resources where they are needed. In recent years, research on diversity techniques, smart antennas and beam forming algorithms have unveiled the potential of these techniques. The aim of this paper is to present and describe the multi node B (MNB) architecture, which could facilitate the controlled and concurrent operation of a number of these techniques in a flexible manner. This paper analyses the link level performance of the proposed architecture compared with the existing STTD (space time transmit diversity) technique already contemplated by the 3GPP standards and highlights further improvements which could be obtained by the proposed architecture. Finally, a detailed speed effect analysis is carried out for the outdoor to indoor and pedestrian test environment.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"458 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115285710","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: 0
Comparison of robustness of MIMO schemes in the presence of interference 干扰条件下MIMO方案鲁棒性比较
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407256
H. Tan, Yang Sun, J. Thompson, D. Cruickshank
{"title":"Comparison of robustness of MIMO schemes in the presence of interference","authors":"H. Tan, Yang Sun, J. Thompson, D. Cruickshank","doi":"10.1109/ISWCS.2004.1407256","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407256","url":null,"abstract":"Multiuser interference (MUI) is a major problem in an orthogonal frequency division multiplexing (OFDM) multiple access system due the absence of unique spreading codes being assigned to different users for separation at the receiver. In our paper, we propose the use of spatial separation techniques to separate users at the receiver. The two proposed interference mitigation techniques, defined as interference cancellation (IC) and interference suppression (IS), can be employed to mitigate interference. However, depending on the scenario and restrictions imposed on either of these two techniques, this requires careful consideration especially in a multiple input multiple output (MIMO) system. Two particular MIMO schemes, V-BLAST and dual Alamouti space time block code (STBC), which are strong candidates for future wireless systems, are introduced. Their robustness in the presence of interference is compared and the selection of appropriate interference mitigation techniques is suggested. Results obtained from our simulator are shown to support this study.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"121 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121703392","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: 0
An efficient algorithm for joint carrier frequency offset and channel estimation in IEEE 802.16 OFDM systems ieee802.16 OFDM系统中联合载波频偏和信道估计的有效算法
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407283
N. Balamurali, D. Jalihal
{"title":"An efficient algorithm for joint carrier frequency offset and channel estimation in IEEE 802.16 OFDM systems","authors":"N. Balamurali, D. Jalihal","doi":"10.1109/ISWCS.2004.1407283","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407283","url":null,"abstract":"This paper develops a novel and simple algorithm to perform joint carrier frequency offset and channel estimation in orthogonal frequency division multiplexing (OFDM) systems. Carrier frequency offset of upto several frequency subcarrier spacings has to be estimated and compensated in order to enhance the OFDM system performance. The time domain synchronization algorithms using the preamble structure provided for fixed broadband wireless OFDM uplink access (IEEE 802.16 LAN/MAN standards) can only measure a frequency offset with an ambiguity equal to an even number of subcarrier spacings, in case of the actual offset being more than a subcarrier spacing. Our proposed algorithm uses the received preamble to jointly estimate this remaining integer part of the frequency offset and the initial channel impulse response using a least squares criterion in an iterative manner. Computer simulations show that the proposed estimator is very robust at low signal to noise ratios (SNRs) and operate near the Cramer-Rao bound for the variance of the frequency offset estimate.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125324970","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: 18
Asia-Pacific satellite communications system 亚太卫星通信系统
1st International Symposium onWireless Communication Systems, 2004. Pub Date : 2004-09-20 DOI: 10.1109/ISWCS.2004.1407251
K. Miyoshi, M. Miura
{"title":"Asia-Pacific satellite communications system","authors":"K. Miyoshi, M. Miura","doi":"10.1109/ISWCS.2004.1407251","DOIUrl":"https://doi.org/10.1109/ISWCS.2004.1407251","url":null,"abstract":"The authors propose herein a large-capacity satellite intranet and dedicated evolutionary communications services for business users, which offer high availability, low cost and security, by using a network that is separate from the Internet. Ka band spot beams enable high-speed transmission of 1.2 Gbps per transponder and 90 Gbps per satellite. By automatic switching to C band during heavy rain, a high availability of 99.95% can be achieved. A satellite transmission cost of 0.3 cents/Mbyte is expected to be attained due to the enormous satellite capacity. In the proposed system, satellites are used for communications traffic between the US and Asian countries and within Asia and Oceania. The system is versatile and is applicable globally.","PeriodicalId":122977,"journal":{"name":"1st International Symposium onWireless Communication Systems, 2004.","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122780854","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: 0
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：604180095
Book学术官方微信