A low-complexity grouped MMSE interference cancellation scheme for OFDMA uplink systems with carrier frequency offsets

In this paper, we consider interference cancellation (IC) schemes for uplink orthogonal frequency division multiple-access (OFDMA) systems with carrier frequency offsets (CFOs). To improve the detection performance without increasing the computational complexity of the detector, we propose a low-complexity multi-stage interference cancellation (MIC) scheme based on a grouped minimum mean squared error (GMMSE) algorithm. In the proposed scheme, a novel IC strategy is employed. The simulation results show that the proposed IC scheme outperforms other existing schemes with considerable low complexity in both subband carrier assignment scheme (CAS) and generalized CAS scenarios.