Communication over Dispersive Wireless Channels: Theory and Methods Based on Physical Principles

无线革命的目标是提供无处不在的无线连接和信息访问。在过去的十年里，随着蜂窝电话和无线局域网卡的普及，朝着这一目标取得了巨大的进展。特别是，空时处理，使用多天线阵列的刺激下，已经成为无线技术的关键使能器。尽管最近在无线通信研究和技术方面取得了进展，但由于我们对共享物理无线信道的基本理解存在重大差距，最先进的技术还远远没有实现无线网络的容量。无线信道所带来的关键挑战是由于其在时间、频率和空间上的分散性，这是由多个空间分布路径上的物理信号传播引起的。这激发了这个项目的核心问题：在分散的无线信道上控制可靠通信的关键因素是什么？在分散的无线信道上通信的基本限制是什么？指导实际系统设计的关键原则是什么？我们将利用一个新的框架，基于物理无线信道的虚拟表示来解决这些多方面的问题。虚拟表示是一个强大的解构工具，用于揭示分散无线信道下的丰富结构。正如我们在这个建议中所展示的那样，虚拟表示框架所提供的见解在无线通信系统的设计和分析中具有深刻而广泛的影响。在这个框架内，我们提出的研究计划有三个广泛的综合目标：

The goal of the wireless revolution is to provide ubiquitous tetherless connectivity and access to information.The last decade has seen great progress towards this goal with cellular phones and wireless LAN cardsnow being commonplace. In particular, space-time processing, spurred by the use of multiple antennaarrays, has emerged as a key enabler of wireless technology. Notwithstanding recent advances in wirelesscommunications research and technology, the state-of-the-art is far from realizing the capacity of wirelessnetworks because of significant gaps in our fundamental understanding of the shared physical wirelesschannel. The key challenges posed by the wireless channel are due to its dispersive nature in time, frequencyand space resulting from physical signal propagation over multiple spatially distributed paths. This motivatesthe central questions at the heart of this project:What are the key factors that govern reliable communication over dispersive wireless channels?What are the fundamental limits on communication over dispersive wireless channels?What are the key principles that guide practical system design?We will leverage a novel framework based on a virtual representation of physical wireless channels toaddress these multi-faceted questions. The virtual representation is a powerful deconstructing tool for unravelingthe rich structure underlying dispersive wireless channels. As we demonstrate in this proposal,the insights afforded by the virtual representation framework have deep and wide ranging implications inthe design and analysis of wireless communication systems. Within this framework, our proposed researchprogram has three broad integrated thrusts: