Author(s): Bashar Ali Farea, Nor Shahida Mohd Shah
Abstract: In this paper, in-phase and quadrature-phase imbalances (IQI) problem in the recent discrete sine transform based Orthogonal frequency division multiple access (DST-OFDMA) and discrete sine transform based single-carrier frequency division multiple access (DST-SC-FDMA) is investigated and compensated. IQI problem is investigated in three scenarios, transmitter IQI scenario (TX IQI scenario), receiver IQI scenario (RX IQI scenario) and transmitter- receiver IQI scenario (TX-RX IQI scenario), with different subcarriers mapping for both FDMA systems. The simulation results show that the mismatch in the phase and amplitude between the two branches of local oscillator in the receiver scenario introduces a significant performance degradation of the both FDMA systems more than transmitter scenario. Thereby, a correction scheme is proposed in this paper in the RX IQI scenario to face the degradation in the performance.