Cooperative antenna concepts for interference mitigation

For future cellular mobile radio systems optimum interference mitigation is one of the key challenges. Cooperative antenna systems promise significant performance gains with respect to throughput, capacity and coverage, but they are difficult to realize in practical systems. Major challenges are channel estimation to many base stations (BS) with high accuracy and data exchange between tightly coupled BSs with low delay. In practical systems cancellation of a limited number of interferers is reasonable, while measurements as well as simulation results show that 40 to 50 interferers might contribute significantly to the resulting interference. For this reason in this paper the interference floor is investigated in more detail as well as a novel combination of interference coordination - reducing the interference floor - with cancellation of a few geographically nearby interferers is proposed.