Spatial multiplexing via antenna switching

A simple scheme for spatially multiplexing two BPSK signals using a switched antenna system with a single RF chain, a shared RF-DC cable and a shared RF-DC feeding circuit is proposed. The idea is to modulate the first BPSK substream to one of the two array elements while exciting the second element parasitically by the field of the first one. The second substream is encoded in such a way to control which of the two elements will be driven. Decorrelating the two BPSK signals at the transmitter side is achieved by mapping the signals onto a set of orthogonal functions while the matching impedance of the two antenna elements is optimized for the maximum outage rate by maximizing the matching efficiency and minimizing the power imbalance between the basis functions, simultaneously.