2007 4th International Symposium on Wireless Communication Systems最新文献_第2页

A Simplified Approach to Multicast Forwarding Gateways in MANET MANET中组播转发网关的一种简化方法

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392375

Y. Lacharite, Maoyu Wang, L. Lamont, L. Landmark

{"title":"A Simplified Approach to Multicast Forwarding Gateways in MANET","authors":"Y. Lacharite, Maoyu Wang, L. Lamont, L. Landmark","doi":"10.1109/ISWCS.2007.4392375","DOIUrl":"https://doi.org/10.1109/ISWCS.2007.4392375","url":null,"abstract":"Simplified multicast forwarding (SMF) provides an optimized flooding mechanism in MANET environments to efficiently propagate multicast packets. The main difference between the SMF and traditional multicast routing is that no multicast tree is built and maintained, and no group membership management is needed. Therefore all the nodes in MANET receive the multicast information. However, a multicast border gateway is required in a MANET to interoperate with other multicast routing protocols in the wired domain as SMF does not make use of traditional multicast method. We propose a MANET SMF gateway implementation solution that addresses the issues encountered within the gateway configuration, such as interaction with the protocol independent multicast protocol (PIM). We will present the results of a tested single-gateway MANET implementation, and will also introduce a proposal for the multiple-gateway scenario. In the IETF MANET working group, the SMF design group also presents proposals for handling multiple gateways; they recommend to apply a <taggerID> to the multicast traffic when multiple gateways are injecting a flow into a MANET area. However this approach implies that equal multicast packets disseminated into the MANET by different gateways have different taggerlD, and hence these packets cannot be detected as duplicates. Our approach differs by preferring the use of hashing by the gateways for marking equal packets injected into the MANET, hence making these equal packets compliant for duplicate detection. This article demonstrates a successful implementation of the gateway functionality and extends its analysis by proposing a solution for the multiple-gateway configuration.","PeriodicalId":261480,"journal":{"name":"2007 4th International Symposium on Wireless Communication Systems","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121599298","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: 11

Downlink DSTBC-WCDMA in a Fast Time-Dispersive Channel 快速时间色散信道中的下行DSTBC-WCDMA

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392391

Edwin M. Umali, Y. Yamao

引用次数: 1

An Efficient Fixed Complexity QRD-M Algorithm for MIMO-OFDM using Per-Survivor Slicing 基于Per-Survivor切片的MIMO-OFDM高效固定复杂度QRD-M算法

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392405

T. Detert

{"title":"An Efficient Fixed Complexity QRD-M Algorithm for MIMO-OFDM using Per-Survivor Slicing","authors":"T. Detert","doi":"10.1109/ISWCS.2007.4392405","DOIUrl":"https://doi.org/10.1109/ISWCS.2007.4392405","url":null,"abstract":"We propose a reduced complexity QRD-M algorithm based on two techniques: Diagonal Loading Preconditioning (DLP) to mitigate the impact of weak main diagonal elements of the channel matrix, and Per-Survivor Slicing (PSS) to allow for pruning of unnecessary branch computations. Both techniques can be combined. In comparison to previously published detectors, both techniques allow for fixed low complexity that is independent of the SNR. For PSS, a local slicer carries out P tentative decisions on possible symbols based on the symbol alphabet A of size |A|. Only for the P symbols closest in Euclidean distance to the received symbol soft estimate, branch metrics are computed, the remaining |A|-P symbols are dropped. M survivors are retained at each stage. In addition, we show that the previously proposed MMSE QRD- M algorithm (MQRD-M algorithm) has an error floor at high SNR. We show that DLP improves the QRD-M algorithm and outperforms the MQRD-M algorithm. In comparison to MQRD-M algorithm, neither the noise variance needs to be estimated, nor a prefilter (which would require a matrix inversion) is needed. Further, in order to take into account the different strengths of the layers, we propose to partition an available fixed number of branches in relation to the SNR of the layers. The proposed PSS technique is improved by this approach. DLP and PSS significantly lower the complexity. For 16-QAM modulation in a 4 times 4 MIMO system, e.g., the number of branches using the proposed PSS technique is 31.25% of the ordinary QRD-M algorithm if M = 16. With DLP used together with PSS, M can be lowered further, so that with 10.2% of the branches of QRD-M algorithm, only a small loss of 1 dB occurs.","PeriodicalId":261480,"journal":{"name":"2007 4th International Symposium on Wireless Communication Systems","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131695659","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

Evaluation of WiMAX Uplink Performance in High Altitude Platforms Cellular System 高空平台蜂窝系统WiMAX上行链路性能评估

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392458

Zhe Yang, A. Mohammed

引用次数: 7

Progressive Hypercube Decoding 渐进式超立方体解码

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392290

F. A. Monteiro, I. Wassell

引用次数: 0

Analyzing IKEv2 Performance when Protecting Mobile IPv6 Signaling 保护移动IPv6信令时IKEv2性能分析

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392368

Z. Faigl, S. Lindskog, A. Brunström

引用次数: 5

On the impact of the pilot density in the channel estimation of MC-CDMA systems 导频密度对MC-CDMA系统信道估计的影响

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392446

C. Ribeiro, A. Gameiro

引用次数: 0

Layered LDGM codes: a capacity-approaching structure for arbitrary rates 分层LDGM代码:任意费率的容量逼近结构

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392293

M. González-López, F. J. Vázquez-Araújo, L. Castedo, J. Garcia-Frías

引用次数: 5

Load-Balanced Cluster-Based Cooperative MIMO Transmission for Wireless Sensor Networks 基于负载均衡集群的无线传感器网络协同MIMO传输

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392411

Tianshi Gao, Lin Zhang, Yi Gai, X. Shan

引用次数: 9

Cross Slot Antenna with U-Shaped Tuning Stub for Ultra Wideband Applications 用于超宽带应用的u形调谐根交叉槽天线

2007 4th International Symposium on Wireless Communication Systems Pub Date : 2007-12-04 DOI: 10.1109/ISWCS.2007.4392353

N. Sargolzaei, D. S. Javan, S. Sadat

引用次数: 57