ITR: Cooperative Wireless Networks

ITR：合作无线网络

• 批准号: 0219892
• 负责人: Hesham El Gamal
• 金额: $ 40万
• 依托单位: Ohio State University Research Foundation -DO NOT USE
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0219892&HistoricalAwards=false
• 关键词: ITR; Cooperative; Wireless; Networks

We are in the midst of a new wireless revolution, brought on bythe adoption of wireless networks for consumer, military,scientific and other applications. Wireless networks are acollection of terminals, or nodes, that are capable oftransmitting and receiving information to nearby nodes usingwireless access methods. The harsh characteristics of the wireless channel provide thefundamental challenge for communication between wireless networknodes. The key to reliable communication over wireless links is theexploitation of diversity, i.e., observation of the sameinformation through different fading conditions. While it ispossible to harness diversity by transmitting the same signal atdifferent times or frequencies, the implied redundancy is costlyfrom a bandwidth perspective. It has been shown, however, thatintroducing additional antennas at the source and/ordestination enables diversity gain without compromise inbandwidth efficiency. Wireless network nodes may or may not be equipped with multipleantennas. How then, can they ensure reliable andefficient communication over the fading wireless channel? In this research, we investigatenovel strategies by which nodestransmit and receive cooperatively, allowingexploitation of spatial diversity gain that would otherwise beunavailable.The lack of structure in ``ad-hoc'' wireless networks isadvantageous from the viewpoint of flexibility,re-configurability, and low management cost. The same lack ofstructure, however, makes the implementation of cooperativestrategies challenging. It may be difficult, for example, to knowwhich of the helper nodes have correctly received the message. Infact, it may be difficult to know which, if any, of the nodes canbe enlisted as helpers. In this research, we solve these problemsthrough the combination of distributed cooperative codingstrategies, clever protocols, and sophisticated signalprocessing techniques. The PIs are leveraging their respective expertise inspace-time coding and blind signal processing to devisepractical strategies for cooperative communication inwireless networks. In addition, this research investigates thefundamental limits on the capacity of cooperative wirelessnetworks through a study of information-theoretic bounds.

我们正处于一场新的无线革命之中，这是由消费者、军事、科学和其他应用采用无线网络带来的。无线网络是一组终端或节点，它们能够使用无线接入方法向附近的节点发送和接收信息。无线信道的恶劣特性为无线网络节点之间的通信带来了根本性的挑战。在无线链路上进行可靠通信的关键是利用分集，即，通过不同的衰落条件观察相同的信息。虽然可以通过在不同的时间或频率传输相同的信号来利用多样性，但从带宽的角度来看，隐含的冗余是昂贵的。然而，已经表明，在源和/或目的地引入额外的天线可以在不影响带宽效率的情况下实现分集增益。无线网络节点可以配备或可以不配备多个天线。那么，他们如何才能确保在衰落的无线信道上进行可靠和高效的通信呢？在这项研究中，我们研究了新的策略，通过该节点transmit和接收合作，allowingexploitation的空间分集增益，否则benavailable.The缺乏结构的“广告”无线网络是有利的，从灵活性，可重新配置，和低管理成本的观点。然而，同样缺乏结构，使得合作战略的实施具有挑战性。例如，可能很难知道哪个帮助节点已经正确地接收到消息。事实上，很难知道哪些节点（如果有的话）可以被用作助手。在这项研究中，我们解决了这些问题，通过结合分布式合作codingstrategies，聪明的协议，和先进的信号处理技术。PI利用他们各自的专业知识--空时编码和盲信号处理，为无线网络中的协作通信设计实用的策略。此外，本研究还通过研究信息论界限来探讨协作无线网络容量的根本限制。