Hybrid-ARQ Interference Channels with Receiver Cooperation

A two-user uplink interference channel with hybrid automatic retransmission request (HARQ) and base station cooperation is analyzed. Two forms of base station cooperation are studied: wireless and wireline cooperation. In wireless cooperation, the first base station that decodes its desired user´s message acts as a relay for the co-channel user via space-time coding during the remaining HARQ rounds. This cooperative HARQ protocol is spectrally efficient despite the half-duplex constraint imposed on wireless transceivers. In wireline cooperation, the base stations cooperate via a wireline link with a fixed capacity. Individual user outage probabilities at each HARQ round are computed for both forms of base station cooperation. Based on these outage probabilities, an upper bound of the total user throughput is determined subject to individual user outage probability constraints after a maximum number of L HARQ rounds. For interference-limited scenarios, base station cooperation provides throughput gains up to a factor of 5.