2FSK modulation for multiuser physical-layer network coding network

The physical-layer network coding (PNC) has become a hot research topic, since it can potentially reduce the transmission time slots and increase the channel capacity. However, current studies are mainly concentrated on three nodes (two users and one relay) network. This paper considers a specific multiuser network that includes M (M>2) users with one relay, and illustrates the transmission scheme and evaluates its bit error rate (BER), information theoretical capacity and anti-noise performance under AWGN channel. Moreover, 2FSK is considered in the proposed network, since it does not need accurate phase tracking. Simulation results show that its information theoretical capacity would decrease significantly with the number of users in this network increase, however the capacity of the proposed scheme is still better than that of the IEEE802.11 networks.