ITR: From Sensor Networks to Multimedia Systems: New Views on MIMO Channels

随着无线通信的日益普及，我们继续寻求按需提供异类数据的高保真传输。为了实现这一目标，必须对现有的无线系统进行重大改进。所提出的研究的主要目的是通过多输入/多输出无线系统的概化来扩展调制和相关接收器设计的技术水平。在理论分析所承诺的使用多个发射和接收天线系统的巨大容量优势的刺激下，空时编码和调制方案的设计和分析受到了极大的关注。实验发射分集系统提供了进一步的希望，现有系统和理论之间的差距可以被弥合。拟议的研究将包括商业无线系统，如蜂窝通信网络，以及更具投机性的系统，如自组织传感器网络。抽象地说，这两个网络在网络参数信息和控制方面代表了极端。蜂窝通信系统的特征是具有简单的层次结构，以基站为中央控制器，适度的功率限制，高度可靠的用户，以及适度的每个小区的用户密度，并且拥有所有活动用户的几乎完整的参数信息。相比之下，传感器网络可能会有嵌套的簇头层次结构，与少量节点进行通信，严重的功率限制，不可靠的节点和密集的部署。我们将考虑三个主要的研究焦点：传感器网络的协作通信；干扰信道的传输分集方案；以及空时方法与多媒体系统的耦合。

ABSTRACT0313392Mitra, UrbashiU of Southern CaliforniaWith the emerging ubiquity of wireless communications, we continue to seek to provide high fidelity transmission of heterogenous data on demand. To fulfill this objective, significant improvements must be made over current wireless systems. The principal aim of the proposed research is to extend the state of the art of modulation and associated receiver designs for multiple-input/multiple-output wireless systems via the generalization of such channels. Spurred by the substantial capacity advantages promised by theoretical analysis for the use of multiple transmit and receive antenna systems, significant attention has been devoted to the design and analysis of spacetime coding and modulation schemes. Experimental transmit diversity systems have offered further hope that the gap between existing systems and theory can be bridged. The proposed research shall encompass commercial wireless systems such as cellular communication networks as well as more speculative systems such as ad hoc sensor networks. Abstractly, these two networks represent extremes in terms of network parameter information and control. A cellular communication system can be characterized as having a simple hierarchy with a basestation as central controller, modest power constraints, highly reliable users, and modest density of users per cell, and possessor of near-complete parameter information of all active users. In contrast, a sensor network will likely have a nested hierarchy of clusterheads communicating with a small set of nodes, severe power limitations, unreliable nodes, and dense deployments. We shall consider three main research foci: collaborative communication for sensor networks; transmit diversity schemes for interference channels; and the coupling of space-time methodswith multimedia systems.