Network MIMO: Overcoming Intercell Interference in Indoor Wireless Systems

``Network MIMO'' is a family of techniques whereby each user in a wireless system is served through all the access points within its range of influence. By tightly coordinating the transmission and reception of signals at multiple access points, Network MIMO transcends the limits on spectral efficiency due to intercell interference. Taking prior information-theoretic analyses of Network MIMO to the next level, this paper quantifies the spectral efficiency gains obtainable under realistic propagation and operational conditions. Our study relies on detailed simulations and, for specificity, is conducted within the framework of the IEEE 802.16e Mobile WiMAX system. All the relevant physical- layer functionalities of Mobile WiMAX are accurately replicated. Furthermore, to facilitate the coordination between access points, we postulate an indoor deployment organized around a Gigabit-ethernet backhaul. The results confirm that Network MIMO stands to provide a multiple-fold increase in spectral efficiency under such conditions.