Design of Optimal Constellation for Massive SIMO Systems with Riemannian Distance

摘要

This paper considers a flat fading noncoherent wireless communication system with a single transmitter antenna and massive multiple receiver antennas, in which the channel coefficients change every two time slots. For such a system, we first parameterize all the high rate constellations which enable each transmitted symbol and the channel coefficients to be uniquely identified in a noise-free case when the number of the receiver antennas goes to infinity. Then, for a noisy channel with the limited number of the receiver antennas, we propose the design of an optimal constellation that maximizes the minimum distance between any two distinct constellation points using the first kind of a Riemannian distance (RD) measure subject to constraints on an average power and total transmission bits. A closed-form optimal solution is attained by first characterizing the optimal structure for any fixed bits on each parameter space and then, finding an optimal bit assignment that further maximizes the achieved minimum distance. One of the significant advantages of such optimal design is that it enables us to develop a fast closedform RD detector. Finally, computer simulations demonstrate that our proposed scheme outperforms the methods in literature for the same system.