Cognitive radio system with a two-user non-binary network-coded cooperative secondary network

We investigate the performance of a network coding based secondary network in a cognitive radio system under spectrum sharing constraints. The secondary network is composed of two users that cooperate to transmit their information to a common secondary destination. The outage probability is analyzed under a given maximum interference constraint set by the primary network as well as to the maximum transmit power limit of the secondary users. Theoretical and numerical results show that the adequate use of network coding by the secondary network can provide significant gains in terms of outage probability and diversity order when compared to non cooperative or traditional cooperative techniques.