Noise Balancing Block Diagonalization precoding for Base Station Cooperation

Previous studies on Base Station Cooperation (BSC) have shown its significant capacity gains. These studies usually ignore the fact that a practical cellular network has a large number of Base Stations (BSs) and to coordinate these BSs will incur heavy signalling overhead, high transmission latency. In order to utilize BSC, a network has to be divided into separate groups, each of which cooperate independently, limiting the number of BSs in one group. This arrangement will make a new kind of interference, which we name it Out of cooperative Group Interference (OGI). We show that OGI can cause severe performance degradation through our simulation study. To solve the problem, we propose a novel Noise Balancing Block Diagonal-ization (NB-BD) precoding algorithm to both cancel self-group interference and accommodate the OGI as extra noise. This NB-BD is simpler, more robust than traditional BD joint precoding and is shown to provide significant performance gains.