Effect of relaying on capacity improvement in wireless local area networks

Wireless relay nodes can improve the capacity of wireless networks. In this work, we integrate wireless relay nodes into the infrastructure of a wireless local area network (WLAN). In particular, we investigate the effect of different relay strategies and optimal utilization of a fixed number of immobile relay nodes, which maximizes the expected throughput capacity of the network. We study how the number of relay nodes, the range of users, transmission power, path loss exponent, and traffic characteristics affect the optimal relay node placement and expected throughput capacity of the network. Our results show that a time-division relay strategy can far outperform a receive-and-retransmit relay strategy. Furthermore, for a wide range of system parameters, optimally placed relay nodes can significantly increase the network expected throughput capacity.