Enhanced Joint Channel and IQ Imbalance Parameter Estimation for Mobile Communications

This letter presents an enhanced joint channel and in-phase and quadrature-phase (IQ) imbalance parameter estimation method for communication systems. The proposed method first estimates the channel impulse response (CIR) with integrated IQ imbalance parameters, which contains twice the number of the original CIR parameters. To exploit the additional redundancy in the initial estimate, the alternating least square (ALS) algorithm is used to estimate the channel and the IQ imbalance parameters in an iterative manner. Particularly, the proposed method can exploit the beneficial linear structure of the initial estimate and largely reduce the required number of the estimated parameters, thereby enhancing the estimation performance. Simulation results demonstrate the efficacy of our proposed scheme in multipath fading channels even with severe IQ imbalance impairments.