Downlink with partially cooperating base stations

For a downlink scenario with two base stations and one receiving mobile, where the base stations are connected by a noiseless finite-capacity backbone, we determine the optimal cooperation and coding strategy. The performance is not influenced by the degree of channel state information at the mobile, but it increases with increasing channel state information at the base stations. If the link capacities exceed finite thresholds, the system achieves full-cooperation performance. The optimal cooperation protocol is a simple one-shot strategy.