The spectrum efficiency of a base station antenna array system for spatially selective transmission

The goal of this paper is to estimate the gain, in terms of system capacity at a given outage probability, which can be obtained by applying antenna arrays in the base stations of a mobile cellular network. For this purpose a propagation model which incorporates the angular distribution of the rays in the vicinity of the mobile is postulated. Also included in the model is the interference from co-channel cells. With the aid of the model, a weight selection algorithm is derived. The proposed system is simulated with different numbers of mobiles per channel in each cell and different numbers of antenna elements in the arrays. Also varied is the cluster size. This is done to determine the optimal trade-off between reduced cluster size and multiple mobiles per channel in each cell. The results show that it is possible to increase capacity between two and twelve times depending on the number of antennas in the arrays and the spread of the local scattering