Joint compensation of transmitter and receiver IQ imbalance in OFDM systems based on selective coefficient updating

approach at each branch of per-tone equalization (PTEQ) structure has been applied for insufficient cyclic prefix (CP) length. Because of the high amount of adaptive filters and their complex adaption process in PTEQ structure, SCU has been proposed. So using this method leads to reduce the computational complexity while the performance is almost being unchanged. Moreover, using set-membership filtering with variable step size is proposed for sufficient CP case to increase convergence speed and decrease the average of calculations. Simulation results show that these algorithms have similar performance in comparison with conventional algorithms while these reduce the amount of calculations. In addition, compensation of the channel effect, transmitter/ receiver in-phase/quadrature-phase (IQ) imbalance are achievable by these algorithms.