Compact MIMO Antennas and HAP Diversity for Enhanced Data Rate Communications

In this paper we address the potential gain of using various compact MIMO antenna array configurations in conjunction with HAP (high altitude platforms) diversity techniques in order to enhance the data rates in HAP communication systems. We also investigate the effects of spatial correlation and mutual coupling between the separate antenna elements on system performance. Simulation results show that although the capacity is degraded by correlation and mutual coupling, we still achieve significant capacity gain compared to the single HAP case. Simulations also show the existence of an optimum separation angle between HAPs that maximizes capacity.