Receive Antenna Shift Keying Modulation Testbed for Wireless Communications Systems

Time Reversal (TR) applied to wireless communications systems has already shown very promising results at low Signal-to-Noise Ratio (SNR). In this paper, we describe a prototype implementing the Receive Antenna Shift Keying (RASK) modulation scheme combined with TR. RASK modulation consists in focusing a signal onto one receive antenna among several antennas. The index of the target receive antenna is updated every symbol duration and is coded by the binary sequence to be transmitted during the considered symbol. For spatial signal focusing, TR pre-filtering technique is used at the transmitter side. In this study, we also propose a very simple and efficient way to discriminate the collected information at the receiver side. This technique allows receivers with low complexity to be implemented in a multiple-input multiple-output (MIMO) configuration. Moreover, we evaluate the performance of RASK modulation according to the number of antennas at the transmitter and receiver side and demonstrate the feasibility of our approach in a realistic scenario.