Optimal Design of Uniform Planar Antenna Arrays for Strong Line-of-Sight MIMO Channels

We investigate the optimal design of uniform planar antenna arrays employed in multiple-input multiple-output communications where a strong line-of-sight (LOS) component is present. A new general geometrical model is introduced to model the LOS channel, which allows for any orientation of the two arrays. Based on this model, we derive the optimal design equations with respect to maximizing Shannon capacity, which turn out to be solvable for several interesting cases. The solutions reveal that the proposed principle is best suited for fixed applications, as e.g. fixed wireless access. The LOS channel matrix is used in a Ricean channel model to evaluate performance under different channel conditions. Results show that even with some deviation from the optimal design, we get good performance compared to the case of uncorrelated Rayleigh subchannels