On Delay Diversity in OQAM/FBMC Based Transmission Schemes

Offset quadrature amplitude modulation based filter bank multicarrier (OQAM/FBMC) is a spectrally efficient alternative to the conventional orthogonal frequency division multiplexing (OFDM) due to its feature of time-frequency localization. However, in presence of the intrinsic interference, it is not as straightforward as OFDM for OQAM/FBMC to benefit from the gains of incorporating multiple-input multiple-output processing, especially for the spatial diversity technique. In this paper, we propose a low-complexity delay diversity (DD) scheme for OQAM/FBMC systems, which is formed by transmitting delayed versions of the same signal on multiple transmit antennas. The associated channel estimation and equalization are also developed for OQAM/FBMC systems with DD. Simulation results verify the effectiveness of the proposed channel estimation method and demonstrate that the proposed DD scheme obtains significant improvements in bit error ratio performance.