2008 IEEE International Networking and Communications Conference最新文献

Enhanced D-Tree - An Index Structure For Window Queries In Location Based Services 增强型D-Tree——基于位置的服务中窗口查询的索引结构

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562704

M. Vijayalakshmi, A. Kannan

{"title":"Enhanced D-Tree - An Index Structure For Window Queries In Location Based Services","authors":"M. Vijayalakshmi, A. Kannan","doi":"10.1109/INCC.2008.4562704","DOIUrl":"https://doi.org/10.1109/INCC.2008.4562704","url":null,"abstract":"Location based services is considered as a killer application in the wireless data market that provide information based on locations specified in the queries. We consider wireless data broadcasting as a way of disseminating information to a massive number of users. To address the issues of responsiveness, energy consumption and bandwidth contention in wireless communications, an index has to minimize the search time and maintain a small storage overhead. A linear index structure based on the D-tree is used to support location dependent queries, which is reduced to planar point queries. In this paper, we propose a modified D-tree index structure for processing location dependent information focusing on window queries via wireless data broadcast in a mobile environment. Hilbert curve is used to reduce the data regions that have to be searched from the whole space. Filtering mechanisms are used to find the real answer set. To improve the query processing two techniques namely, fixed grid assignment by which the given space is partitioned into several disjoint sub-grids and caching mechanism that improves access latency were used.","PeriodicalId":339313,"journal":{"name":"2008 IEEE International Networking and Communications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128984237","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

On Error-Constrained Data Throughput of Rapid Symbol Duration Adaptation with Imperfect Channel Information 不完全信道信息下符号持续时间快速自适应的错误约束数据吞吐量研究

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562699

D.C. Lee, M. Naeem, S. Xue

引用次数: 1

Spectral Detection and Time Delay Estimation of a Phase Coded Signal Corrupted by Colored Observation Noise 彩色观测噪声干扰下相位编码信号的频谱检测与时延估计

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562698

S. Awais, M.B. Malik

引用次数: 0

A Cross-Layer Optimization Approach for Efficient Data Gathering in Wireless Sensor Networks 无线传感器网络中高效数据采集的跨层优化方法

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562700

T. Canli, F. Nait-Abdesselam, A. Khokhar

{"title":"A Cross-Layer Optimization Approach for Efficient Data Gathering in Wireless Sensor Networks","authors":"T. Canli, F. Nait-Abdesselam, A. Khokhar","doi":"10.1109/INCC.2008.4562700","DOIUrl":"https://doi.org/10.1109/INCC.2008.4562700","url":null,"abstract":"Data collection techniques in wireless sensor networks (WSN) suffer from heavy congestion particularly at nodes closer to the sink node. In order to combat this problem, either complex MAC layer protocols have been proposed or non scalable data collection solutions have been designed. We propose a novel cross layer optimization approach that assumes a very simple MAC protocol and makes use of both routing and MAC layers information to reduce congestion, improve delivery ratio, and optimize energy usage. The proposed approach uses multiple disjoint collection trees, rooted from sink, with non overlapping duty cycles. At the MAC layer, we exploit the fact that nodes that are on different data collection trees need not to communicate with each other, hence the SMAC based wake up and sleep schedule for each tree is different. Existing multiple tree based data collection protocols have been designed primarily for fault tolerance or load balancing. For MAC layer part of our protocol, we have modified the SMAC code available in ns-2.28 to simulate our data collection scheme. Our scheme improves the data delivery ratio up to 40% for regular traffic, and reduces energy consumption by 30%.","PeriodicalId":339313,"journal":{"name":"2008 IEEE International Networking and Communications Conference","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133380138","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: 15

UMTS: High Speed Packet Access (HSPA) Technology UMTS:高速分组接入(HSPA)技术

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562669

S.I. Shah

{"title":"UMTS: High Speed Packet Access (HSPA) Technology","authors":"S.I. Shah","doi":"10.1109/INCC.2008.4562669","DOIUrl":"https://doi.org/10.1109/INCC.2008.4562669","url":null,"abstract":"As of July 31, 2007, there are over 522 million 3G subscribers in the world (source: 3gtoday.com). Out of these 130 million are on UMTS, a growth of almost 100% in one year. Data services are expected to grow significantly within the next few years. Current 2.5 G and 3 G operators are already reporting that a significant proportion of usage is now due to data, implying an increasing demand for high-data-rate, content-rich multimedia services. Although current Release 99 WCDMA systems offer a maximum practical data rate of 384 kbps, the 3rd Generation Partnership Project (3GPP) have included in Release 5 of the specifications a new high-speed, low-delay feature referred to as High Speed Downlink Packet Access (HSDPA). HSDPA also known as Release 5, provides significant enhancements to the Downlink compared to WCDMA Release 99 in terms of peak data rate, cell throughput, and round trip delay. This is achieved through the implementation of a fast channel control and allocation mechanism that employs such features as Adaptive Modulation and Coding and fast Hybrid Automatic Repeat Request (HARQ). Shorter Physical Layer frames are also employed High Speed Uplink Packet Access (HSUPA) (UMTS Release 6) complements the High Speed Downlink Packet Access (HSDPA) technology. As the name suggests the improvement is in the uplink where the theoretical uplink data rate can be up to 5.76 Mbps. Together, HSDPA and HSUPA offer reduced latency and much higher data rates on the downlink and uplink, theoretically as high as 14.","PeriodicalId":339313,"journal":{"name":"2008 IEEE International Networking and Communications Conference","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126253266","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: 8

Influence of pilot symbol configuration on data-aided phase noise estimation from a DCT basis expansion 导频符号配置对DCT基扩展数据辅助相位噪声估计的影响

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562696

J. Bhatti, M. Moeneclaey

引用次数: 8

Low Correlation Sequences for CDMA 用于CDMA的低相关序列

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562671

G. Garg

引用次数: 0

A simple cross-layer approach to reduce duplicate acknowledgements for TCP over WLAN 一个简单的跨层方法，以减少重复确认的TCP在WLAN上

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562693

A. Hussain, M. Akbar, M. A. Cheema

{"title":"A simple cross-layer approach to reduce duplicate acknowledgements for TCP over WLAN","authors":"A. Hussain, M. Akbar, M. A. Cheema","doi":"10.1109/INCC.2008.4562693","DOIUrl":"https://doi.org/10.1109/INCC.2008.4562693","url":null,"abstract":"TCP was designed to perform on wired networks, where packet loss is mostly caused by congestion, as compared to wireless networks, where losses due to error in channel are more likely. Hence TCP respond to all kind of losses by invoking congestion control and avoidance schemes resulting in performance degradation. Several solutions for the improvement of TCP over wireless link have been proposed which are divided into four broad categories, namely, transport layer, link layer, cross layer and split connection schemes. Wireless link layer protocol 802.11 is required to receive acknowledgment of every frame it sends, which is too conservative. This paper presents an improved delayed-ACK for wireless LANs (IDAWL), a new cross layer approach which reduces acknowledgments at link layer which a sender get, hence it eliminates the duplication of acknowledgement at link layer and transport layer. It is variation of DAWL in which ACK number of the TCP-ACK is sent at a MAC level and TCP ACK is discarded. This cross-layer approach leads to the local generation of the TCP acknowledgment of the downstream TCP data at the access point (AP). The performance of the proposed scheme is evaluated over NS-2 by comparing it with IEEE 802.11 and DAWL. The results show a significant improvement in TCP goodput.","PeriodicalId":339313,"journal":{"name":"2008 IEEE International Networking and Communications Conference","volume":"191 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116782277","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: 5

Performance Loss Due to Imperfect Knowledge of Offered Load in CAC Policies 由于不完全了解CAC策略中提供的负载而导致的性能损失

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562691

M. Naeem, D.C. Lee

引用次数: 0

Quality of Service: Model, Algorithms and Architectures 服务质量:模型、算法和体系结构

2008 IEEE International Networking and Communications Conference Pub Date : 2008-05-01 DOI: 10.1109/INCC.2008.4562672

A. Haque

引用次数: 0