Efficient MISO system combining Time Reversal and OFDM/OQAM

Applying OFDM/OQAM system to multiple antennas systems is expected to be a very efficient system because optimally exploiting both bandwidth and spatial diversity. Nevertheless, combining these two techniques ineluctably leads to a system with low freedom degrees at the transmitter side, in terms of number on antenna for example or to receivers with high complexity in order to deal with generated interferences.This article proposes to use Time Reversal as precoding of a OFDM/OQAM system irrespective of the number of transmit antennas in a MISO system. As already demonstrated for MISO OFDM system, the equivalent channel coefficients are proven to be purely real, and thus received signals can more efficiently and coherently added at the receiver side. In fact, this ”equivalent channel” allows, under some assumptions, to totally suppress the residual interference. Bit Error Rate simulation results are finally provided showing the efficiency of the global system.The computational simplicity and the results also indicates that the proposed system is well suited for large MISO systems.