Time reversal receive antenna shift keying on MIMO LOS channel

Receive Antenna Shift Keying (RASK) is a Spatial Modulation (SM) transmission scheme that has recently been under study because of its low detection complexity and its ability to increase the spectral efficiency when combined with classical IQ modulation schemes. The idea is that the transmitter uses a focusing technique to target one of the receive antennas. The transmitted information is coded depending on the index of the receive antenna that have been targeted. Note that in this case, the sent signal does not contain any information, that's why RASK can be combined with any classical IQ modulation. Different focusing techniques could be used to target a receive antenna. In this study, the Time Reversal preprocessing technique is used at the transmitter side. In this paper, theoretical performance of the Bit Error Rate and of the focusing gain are established for the RASK scheme in a MIMO Line-of-Sight configuration with two receive antennas. Also, a testbed is evaluated and used to provide RASK performance in realistic conditions.