2008 11th IEEE Singapore International Conference on Communication Systems最新文献_第10页

A new hop rate estimation method for high-speed frequency-hopping signals 一种新的高速跳频信号跳频估计方法

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737399

Yingke Lei, Yanhua Wu

引用次数: 3

Optimal fully adaptive power management protocols for asynchronous multi-hop ad hoc wireless networks 异步多跳自组织无线网络的最佳全自适应电源管理协议

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737248

Zi-Tsan Chou, Yu-Hsiang Lin, R. Jan

{"title":"Optimal fully adaptive power management protocols for asynchronous multi-hop ad hoc wireless networks","authors":"Zi-Tsan Chou, Yu-Hsiang Lin, R. Jan","doi":"10.1109/ICCS.2008.4737248","DOIUrl":"https://doi.org/10.1109/ICCS.2008.4737248","url":null,"abstract":"In wireless ad hoc networks, IEEE 802.11 power management may completely fail if power-saving (PS for short) stations are out of synchronization. To fix this problem, proposed various cyclic quorum-based power management (CQPM) protocols, which, however, may also completely fail if some PS stations have different schedule repetition intervals (SRIs). To conquer all these problems, we propose the OAPM protocol, which has the following attractive features. (i) By means of novel factor-hereditary quorum space techniques, OAPM ensures that two PS neighbors can discover each other in finite time regardless of their clock difference and their individual SRIs. (ii) Given the maximum value of SRI, Smax, the number of tunable SRIs for every PS station is Smax. (iii) The idle duty cycles for all SRIs are minimal. (iv) The time complexity of OAPM neighbor maintenance is constant. (v) A cross-layer SRI adjustment scheme is proposed such that a PS station can adaptively tune its SRI according to traffic QoS requirements. Primary simulation results show that OAPM achieves better energy efficiency than existing CQPM protocols.","PeriodicalId":208126,"journal":{"name":"2008 11th IEEE Singapore International Conference on Communication Systems","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121379411","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

Rejection of AR-type interference in DS spread spectrum systems with improved code-aided technique 改进码辅助技术抑制DS扩频系统中ar型干扰

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737229

Cheng Wang, R. Ying, Yuhang Yang, Chen He

引用次数: 1

Soft-quantized demodulation for BPSK over discrete-time memoryless fading channel 离散时间无记忆衰落信道上BPSK的软量化解调

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737307

Qiuliang Xie, Kewu Peng, Jian Song, Changyong Pan, Zhixing Yang

引用次数: 2

A SNR-insensitive Doppler shift estimator in wireless communications 无线通信中信噪比不敏感的多普勒频移估计器

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737234

Jingyu Hua, L. Meng, Xiaojian Xu, Zhijiang Xu, Dongming Wang

引用次数: 0

A modified precoding scheme for MIMO downlink channel with imperfect CSIT 一种改进的具有不完全CSIT的MIMO下行信道预编码方案

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737304

Peng Cao, Guixia Kang, Ningbo Zhang, Ping Zhang

引用次数: 3

A channel estimation method for NC-OFDM systems in cognitive radio context 认知无线电环境下NC-OFDM系统的信道估计方法

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737173

Shenmin Zhang, Jun Wang, Shaoqian Li

{"title":"A channel estimation method for NC-OFDM systems in cognitive radio context","authors":"Shenmin Zhang, Jun Wang, Shaoqian Li","doi":"10.1109/ICCS.2008.4737173","DOIUrl":"https://doi.org/10.1109/ICCS.2008.4737173","url":null,"abstract":"In orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems, the sub-carriers, which span the spectrum used by licensed users (LUs), should be deactivated to avoid interference. The resulted OFDM system is called non-contiguous OFDM (NC-OFDM) system. For NC-OFDM systems, as no pilot symbols can be transmitted over these deactivated subcarriers, the conventional modified least square channel estimation can not be applied. In this paper, we propose a new channel estimation method to address this issue. In the proposed channel estimation, we use the LS channel estimation to obtain the channel fading coefficients associated with the subcarriers over which the pilot symbols are transmitted. Furthermore, we compute the time domain channel pulse response based on the basic principle of Fourier transform. Then, we adopt inverse discrete Fourier transform (IDFT) based channel estimation noise reduction to improve the channel estimation accuracy. For slow time-varying channel, we also propose to use pilot-block average based channel estimation noise reduction to further improve the channel estimation performance. Simulation results validate our proposed channel estimation method.","PeriodicalId":208126,"journal":{"name":"2008 11th IEEE Singapore International Conference on Communication Systems","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127364327","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

Low-complexity turbo equalization for single-carrier systems without cyclic prefix 无循环前缀单载波系统的低复杂度涡轮均衡

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737351

Dongming Wang, Chao Wei, Zhiwen Pan, X. You, Chung Hyun Kyu, Jeong Byung Jang

引用次数: 10

MCAD: Multiple connection based anomaly detection MCAD:基于多连接的异常检测

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737333

Xin He, S. Parameswaran

引用次数: 4

QoS provisioning for VoIP over wireless local area networks 无线局域网VoIP的QoS提供

2008 11th IEEE Singapore International Conference on Communication Systems Pub Date : 2008-11-01 DOI: 10.1109/ICCS.2008.4737317

Eng Hwee Ong, J. Khan

{"title":"QoS provisioning for VoIP over wireless local area networks","authors":"Eng Hwee Ong, J. Khan","doi":"10.1109/ICCS.2008.4737317","DOIUrl":"https://doi.org/10.1109/ICCS.2008.4737317","url":null,"abstract":"With proliferation of the IEEE 802.11 WLAN and the emerging 802.11n standard, the WLAN is poised as a promising ubiquitous networking technology to support VoIP services, which is gaining popularity due to their high cost efficiency. However, the 802.11 WLAN is not designed to support delay sensitive traffic such as VoIP. This problem is magnified during a handover as user roam the WLAN network resulting in excessive handover latency and consequently packet loss. In addition, a 802.11 WLAN handover process is predominantly based on the physical layer detection without QoS considerations. This often causes overloading of access points and consequently all its associated connections would suffer from high delay, resulting in unacceptable QoS for the VoIP services. The former can be resolved by reducing handover latency to achieve seamless handover and the latter can be mitigated by employing link layer detection in the 802.11 WLAN handover process and having an appropriate admission control scheme. In this paper, we proposed an integrated load balancing scheme incorporating (i) QoS-based fast handover to support seamless handover by eliminating both detection and scanning phases from the 802.11 WLAN handover process; and (ii) soft admission control to protect QoS of existing voice connections when resources are low. This synergy guarantees service QoS during and after handover respectively. Simulations showed that our proposed integrated load balancing scheme is capable of providing seamless handover and QoS enhancements in terms of increased throughput, reduced packet loss and bounded delay when considering heterogeneous voice traffic of different packetization intervals. Particularly, our proposed scheme effectuate QoS balance of both delay and throughput which jointly optimize overall system utilization.","PeriodicalId":208126,"journal":{"name":"2008 11th IEEE Singapore International Conference on Communication Systems","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131842771","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: 17