Joint Transmitter-Receiver Code Design for Spread-FBMC/OQAM

Filter bank multi-carrier/offset quadrature amplitude modulation (FBMC/OQAM) is an alternative approach to orthogonal frequency division multiplexing (OFDM) system, which overcomes the shortcomings of OFDM by using well-localized prototype filters. In FBMC/OQAM, real-valued symbols are transmitted and the generated pure imaginary-valued intrinsic interference is removed by taking the real part of the demodulated signal. In literature, it has been shown that if the spread spectrum coding is combined with FBMC/OQAM, complex orthogonality is achieved. In this paper, spreading code at the transmitter and despreading code at the receiver are jointly designed based on the channel state information. An iterative algorithm is proposed to obtain transceiver codes. The proposed algorithm is derived from an optimization problem, in which signal to noise plus interference ratio (SINR) is maximized. Simulation results show that the proposed iterative algorithm overcomes other spread-FBMC/OQAM systems in terms of bit error rate (BER).