Steady state analysis of coded cooperative networks with HARQ protocol

We consider a network with an arbitrary number of nodes, where transmission of data packet is enhanced by a medium access control protocol that allows cooperation among nodes and solves transmission failures by an automatic repeat request (ARQ) protocol. Nodes operate in half-duplex mode and may interfere with each other as no coordination is assumed. In this scenario, we first derive the outage probability for a given number of interfering nodes and then relate the interference level to the single node behavior. We analyze the network behavior with a steady state analysis that matches the number of interfering nodes with the number of ARQ retransmissions. Two alternatives for cooperation are considered: decode and forward (DF) cooperation and multiple input-single output (MISO) cooperation, where for each packet transmission either one node transmits at a given time or two cooperating nodes transmit simultaneously. In our steady state analysis we also include an opportunistic version of DF, where cooperation is activated only when the quality of the cooperator-destination link is better than that of the source-destination link. Moreover, we investigate cooperator selection based on its distance to the destination.