Optimum antenna topologies and adaptation strategies for SDMA

We investigate various antenna topologies and synchronization strategies in conjunction with spatial-reference (SR) algorithms for a macrocell base station antenna array. The directions-of-arrival (DOA) and the powers of the incoming: signals are determined by a ray tracing program, which allows for a realistic modeling of the mobile radio channel. Our results show that the performance of any array structure is determined by its aperture and not by its topology. A synchronization scheme based on both the correlation properties and signal-to-noise-and-interference (SNIR) values within the training sequence is found to give optimum performance.