Channel shortening and equalization of OFDM/CDMA systems over doubly selective fading channels

The performance of orthogonal frequency division multiplexing/code-division multiple-access (OFDM/CDMA) system is featured by the resistance to frequency selective fading and the support of multiple user access. However, OFDM/CDMA system suffers from multiple-access interference (MAI) and doubly selective fading in highly mobile channel. Based on basis expansion model (BEM), this paper proposes a receiver with time domain channel shortening filter cascaded with one-tap frequency domain equalizer for down-link multiple-input multiple-output (MIMO) OFDM/CDMA system over doubly selective fading channel. Simulation results show that the proposed receiver not only suppresses multiple-access interference but also equalizes the time and frequency selectivity.