Multi-Hop Cooperative Communication Technique for Cognitive DF and AF Relay Networks

摘要

In this paper, we analyze the performance of cognitive multi-hop networks employing the two most common cooperation protocols, decode-and-forward (DF) and amplify-and-forward (AF). In order to provide the primary quality of service, strict limits on the transmit powers of the secondary nodes are imposed. Considering transmissions over independent but not necessarily identically distributed (i.n.i.d.) Rayleigh fading channels, an exact closed-form expression for the outage probability (OP) of the secondary transmission is derived for cognitive DF relay networks under the constraint of satisfying a required OP of the primary transmission. In addition, for the cognitive AF relay networks, a lower bound for the OP and an upper bound for the symbol error probability of the secondary transmission under considering constraint on the received-interference at the primary destination is obtained. For additional insights, the diversity order for both cases is also provided .