Cooperative multicast in wireless networks

Abstract

Wireless communication has fundamental impairments due to multi-path fading, attenuation, reflections, obstructions, and noise. More importantly, it has historically been designed to mimic a physical wire; in concept other communicators in the same region are viewed as crossed wires. Many systems overcome these limitations by either speaking more loudly, or subdividing the space to mimic the effect of a separate wire between each pair. This thesis will construct and test the value of a cooperative system where the routing and transmission are done together by using several of the radios in the space to help, rather than interfere. The novel element is wireless, cooperative multicast that could be the basis for a new broadcast distribution paradigm. In the first part of the thesis,. we investigate efficient ways to construct multicast trees by exploring cooperation among local radio nodes to increase throughput and conserve energy (or battery power), whereby we assume single transmitting node is engaged in a one-to-one or one-to-many transmission. In the second part of the thesis, we further investigate transmit diversity in the general context of cooperative routing, whereby multiple nodes are allowed for cooperative transmissions. Essentially, the techniques presented in the second part of the thesis can be further incorporated in the construction of multicast trees presented in the first part.