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绳连接和访问信息。在过去的十年中，随着移动电话和无线LAN卡的普及，这一目标取得了巨大的进步。特别是，在使用多个天线阵列的推动下，时空处理已成为无线技术的关键推动因素。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，最先进的无线网络远远没有实现其能力。无线信道的关键挑战在于其在时间、频率和空间上的色散特性，这是由于物理信号在多个空间分布的路径上传播所导致的。这激发了这个项目的核心问题：管理分散无线信道上的可靠通信的关键因素是什么？分散无线信道上的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？我们将利用基于物理无线信道虚拟表示的新框架来解决这些多方面的问题。虚拟表示是解构色散无线信道下丰富结构的有力工具。正如我们在本提案中所展示的，虚拟表示框架所提供的见解对无线通信系统的设计和分析具有深刻而广泛的影响。在这个框架内，我们建议的研究计划有三个广泛的综合推动力：

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: