Outage analysis of various cooperative strategies for the Multiple Access Multiple Relay Channel

In this paper, we study the individual and common symmetric ∊-outage achievable rates of various cooperative strategies adapted to the slow fading Multiple Access Multiple Relay Channel (MAMRC). Channel links are independent and subject to slow Rayleigh fading and additive white Gaussian noise. No Channel State Information at the Transmitter (CSIT) is available. Common to all investigated cooperation schemes are the following assumptions: (1) The sources are independent and want to communicate their messages to a single destination with the help of multiple relays using Joint Network Channel Coding (JNCC) and Decoding (JNCD); (2) Each relay is half-duplex and applies a Selective Decode and Forward (SDF) cooperative strategy, i.e., it forwards a deterministic function of the source messages that are decoded without errors. The cooperation schemes differ in the assignment of the available channel uses to the sources and the relays, ranging from the less efficient orthogonal assignment where sources and relays are given non-overlapping channel uses to the most efficient one where sources and relays can transmit simultaneously in all available channel uses.