Network interference cancellation

Due to the broadcasting nature of wireless transmission, concurrently active links can cause mutual interference to each other. This greatly limits the throughput, as well as, results in poor communication reliability especially for wireless systems with multiple links or hops. To overcome this limitation, many interference cancellation techniques, which have mainly focused on the interference among single-hop links, have been designed. In this paper and in contrast to most previous work, we present an efficient method, which we refer to as network interference cancellation or NICE, for effectively mitigating the interference from multi-hop transmissions. This method will make use of the prior knowledge about the interference, which an interfered node can obtain by receiving and processing the signals from the source node of a multi-hop transmission. Two NICE protocols, namely, decode-and-cancel, and amplify-and-cancel are proposed and analyzed. The two proposed protocols will be considered in relay-assisted wireless access networks as well as wireless ad hoc networks without fixed infrastructure to demonstrate the potential of NICE. It will be shown that by using NICE, more links are able to transmit simultaneously in the same frequency band, thereby, highly improving the spatial reuse of spectrum along with the throughput. Numerical results will also show that both of the two NICE protocols can achieve more than 30% throughput gain over conventional interference free scheduling methods.