On Base Station Cooperation Schemes for Uplink Network Mimo under a Constrained Backhaul

An increasing demand for higher spectral efficiencies in mobile communications will require next generation cellular systems to employ a dense reuse of spectrum in combination with smart interference mitigation or cancellation schemes. Recent publications have revealed the large potential spectral efficiency and fairness gains achievable with multi-cell cooperative schemes, where multiple base stations jointly receive or transmit signals connected to multiple terminals, often referred to as network MIMO. One main issue, however, is the large extent of backhaul capacity required between cooperating base stations. In this paper, we focus on the cellular uplink and investigate the information theoretical limits of joint detection under a constrained backhaul. We propose a framework that incorporates different concepts from information theory and allows us to observe the benefit of different kinds of information exchange between the base stations. Monte Carlo simulation results suggest that a next generation cellular system should ideally adapt the base station cooperation scheme according to the current channel realization.