Carrier sensing range analysis in a general IEEE 802.11 network with physical‐layer network coding

Abstract

In this paper, we investigate the carrier sensing range (CSR) of a general 802.11 network with physical‐layer network coding (PNC). We aim to derive a sufficient CSR that can prevent the hidden‐node collisions in a general 802.11 PNC network. The analysis includes two steps. First, we analyze the six link‐to‐link interference cases in an 802.11 PNC network to show that the mutual interference will be most severe when each node in the network initiates a two‐hop end node link. Second, we consider the worst interference case that all concurrently transmitting links in the network are two‐hop end node links and placed in the densest manner and develop a closed‐form expression of a sufficient CSR that prevents the hidden‐node collisions in a PNC network. From the analysis results, we find that to prevent the hidden‐node collisions, the CSR in PNC network should be bigger than the one in traditional non‐network‐coding network. Furthermore, we carry out extensive simulations to find out the throughput gain of PNC scheme in a general wireless network when considering the impact of CSR. Simulation results show that compared with the non‐network‐coding scheme, PNC scheme has throughput gain when a large proportion (i.e., 90%) of links in the network are two‐hop links and the link density has little effect on the throughput gain of PNC scheme. Copyright © 2014 John Wiley & Sons, Ltd.