Collaborative Research: Signal Processing in Wireless Ad Hoc Networking

合作研究：无线自组织网络中的信号处理项目摘要移动自组织网络（MANDIONAL）在基站不可用或建立成本太高的区域/情况下是非常理想的。 移动性导致的基础设施缺乏、连接时断时续以及拓扑结构的频繁变化给移动自组网的研究带来了巨大的挑战。 虽然大多数以前的努力主要集中在网络层，有令人信服的理由支持最近的信息理论和信号处理研究表明，一个综合的方法，寻求跨层的多样性开发可以导致更富有成效的结果。 本项目的目标是开发一个框架的通信，网络，和信号处理技术的MANNETWORK通过利用节点的合作，在物理层，介质访问，和网络层。 其中包括三个不同但又相互交织的研究方向：第一个是发展无线中继信道的分布式调制理论，包括无线中继信道特性的研究，中继网络相干、差分和非相干通信的调制和检测，中继节点的功率分配和布置。 第二个方向是开发带宽高效和延迟容忍的协作编码方案，以解决编码协作中特有的几个问题，包括由来自中继的重复传输引起的带宽扩展、由于中继的分布位置引起的节点不稳定性以及可扩展性（即，当实现分布式代码的某些协作节点由于衰落而失效时适度降级的能力）。 第三个方向是探索通过并行中继的网络，并开发考虑到无线电信号的实际特性并为多样性开发提供灵活框架的网络协议。

Collaborative Research: Signal Processing in Wireless Ad Hoc NetworkingProject AbstractMobile ad hoc networks (MANETs) are highly desirable in areas/situations where base stations are unavailable or too expensive to establish. Lack of infrastructure, intermittent connectivity, and frequent changes in topology due to mobility present significant challenges in the research of MANETs. While most prior efforts were primarily focused on the networking layer, there are compelling reasons supported by recent information theory and signal processing studies which indicate that an integrated approach seeking cross-layer diversity exploitation can lead to more fruitful results. This project follows that path.The objective of this project is to develop a framework of communication, networking, and signal processing techniques for MANETs by exploiting node cooperation at the physical, medium access, and networking layers. Three different but intertwined research directions are involved, Specifically, the first is to develop a distributive modulation theory over wireless relay channels, covering investigation of the characteristics of wireless relay channels, modulation and detection for coherent, differential and non-coherent communications for relay networks, power allocation and placement of relay nodes. The second direction is to develop bandwidth-efficient and delay-tolerant cooperative coding schemes to address several issues that are unique in coded cooperation, including bandwidth expansion caused by repetitive transmissions from relays, node asynchronism due to distributive locations of relays, and scalability (viz., the capability to degrade gracefully when some cooperating nodes that implement a distributive code fail because of fading). The third direction is to explore networking by parallel relays and develop networking protocols that take into account the realistic characteristics of radio signals and provide a flexible framework for diversity exploitation.