Rate Region of the Multi-Cell Multiple Access Channel under Backhaul and Latency Constraints

Recently, multi-cell joint transmission and joint detection schemes have been identified as promising features of next generation mobile communications systems, as they enable to actively exploit inter-cell interference rather than treating it as noise. Both for uplink and downlink, concrete algorithms have been proposed, and strong increases in spectral efficiency and system fairness have been predicted. Besides posing strong requirements towards the time and frequency synchronization of communicating entities, one essential problem connected to multi-cell cooperative signal processing is the large extent of backhaul required between base stations and an increased detection latency. In this paper, we focus on the latter two aspects in the context of a cellular uplink. We consider different schemes of multi-cell cooperative detection and introduce a framework that allows to derive general backhaul- or latency-constrained rate regions for multi-cell multiple access channels (MAC).