Low Backhaul Distributed Detection Strategies for an Interference Limited Uplink Cellular System

Abstract

This paper deals with multiuser detection through base station cooperation in uplink interference limited scenarios. At high frequency reuse, each base station not only receives signals from the desired user but also from the co-channel interferers in the neighboring cells. We propose distributed interference mitigation which in turn requires joint scheduling of the users onto resources so as to permit sequential processing of the received signals at various cooperating base stations. The detected information bits or their reliability information is passed on from one base station to another, enabling better detection of the received data streams there. Since hard bits or quantized reliability information is transferred the backhaul traffic required for cooperation between the base stations is reduced, and is always less than joint detection for a few base stations in cooperation. The proposed strategies are to be used together with joint detection in a cellular network to minimize total backhaul traffic. Different sequential cooperation strategies have been investigated giving better or comparable performance to that of an isolated single user depending upon the amount of backhaul invested.