Interference Management for Cooperative Relay

While substantial research efforts have been invested on examining capacity improvement of cooperative relay, few have considered its impact on network performance, particular in the presence of interference. Our work provides a reference for effectiveness of cooperative diversity in interference limited ad hoc networks. Cooperative relay exploits spatial diversity available through cooperative terminal's relaying signals for one another, while with such forms of diversity comes the penalty of extra interference to other neighboring terminals. We demonstrate that careless usage of cooperative relay raises service blocking probability, and there is a tradeoff between spatial diversity and service disturbance through interference. We propose to incorporate the process of relay selection with that of channel access to achieve a balance of such tradeoff.

In this work, we consider three fundamental research issues which we believe are necessary to implementing cooperative diversity in ad hoc networks: choosing the appropriate relay, choosing the appropriate cooperative strategy, and resource allocation. We propose several policies for relay selection and two scheduling strategies for channel allocation. We observe that system-oriented relay selection and collaborative scheduling strategies are essential for interference limited systems.

On the Effectiveness of Cooperative Diversity in Ad Hoc Networks: A MAC Layer Study
Haitao Zheng, Yan Zhu, Cong Shen, Xiaodong Wang
PA, March 2005
[Abstract, PDF ]

Interference Management for Cooperative Relay in Ad Hoc Networks
Haitao Zheng, Yan Zhu
in preparation

Slides: ICASSP 05  
Haitao Zheng, April 16,?005