Low Complexity ZF Receiver Design for Multi-User GFDMA Uplink Systems

This paper presents a low complexity receiver for multi-user uplink transmission using generalized frequency division multiplexing (GFDM). By exploiting the frequency spreading filter in the GFDM, the banded and circulant properties of the frequency transformed modulation matrices of individual users are developed. According to the newly developed properties in the frequency domain, a novel low complexity zero-forcing (ZF) receiver is developed for multi-user GFDM uplink systems in the frequency selective channels. The proposed receiver can be realized by successive discrete Fourier transforms and one-tap equalization, avoiding the huge computation caused by the inverse of the large dimensional equivalent system matrix. Simulation results show that the proposed receiver provides nearly the same symbol error rate as the traditional ZF equalizer with substantially reduced computational complexity.