On Performance of Multi-Timeslots Network Coding (MTNC) in Wireless Relay Networks

Considering a wireless relay network composed of a source, several relays and a destination where the source transmits data packets to the destination through both direct and relay paths, a multi-timeslots network coding (MTNC) scheme is proposed to combat the lossy nature of wireless channel where the relay nodes with satisfying relay-destination (r - d) channel state firstly perform network coding on the successfully decoded data packets received from the source at previous timeslots and then forward the coded version to the destination. We focus on three metrics - Ergodic capacity, outage probability and symbol error rate to evaluate the performance of MTNC scheme and the replication-based relay (RR) scheme where a "best" relay node is selected out to replicate and forward the data packet. Precise closed form expression of ergodic capacity, tight estimated closed form expression of outage probability (OP) and symbol error rate (SER) are derived for both schemes, and also numerical results are shown to prove the gain of network coding. However, with increasing of the relay number, the improvement of outage probability and SER is limited.