Energy-efficient Cooperative Transmission in Wireless Networks with Limited Channel State Information

This paper tackles the problem of minimum-energy cooperative transmission in wireless networks under the assumption of limited channel state information at the transmitters. It is assumed that only the average statistics of the fading channels are known to the transmitters. The objective here is to jointly optimize the set of relays and the transmission powers for both the broadcasting and cooperative transmission phases while satisfying probabilistic signal-to-noise ratio (SNR) constraints at the relays and at the destination node. Increasing the broadcasting power expands the set of potential relays and decreases the required power for cooperative transmission. Hence, there is a trade-off in the selection of the power values, which is addressed in this work by using a chance-constrained optimization framework. Simulations are presented to demonstrate the efficacy of the proposed approach.