Spatial half-duplex: Precoder design and experimental evaluation

In this paper, we study spatial half-duplex, where an antenna array is partitioned such that a subset of antennas is used for transmission, and others for reception in the same time and frequency. We use transmit-precoders to partition the antennas and design optimal precoders under two approaches. In one approach, precoder minimizes self-interference, for fixed downlink-rate. In another approach, precoder maximizes downlink-rate, for fixed self-interference power. For both approaches, the problems are modeled as convex programs. We characterize the performance of precoders using over-the-air channel measurements and identify the regimes in which spatial half-duplex strictly outperforms time or frequency half-duplex.