Low Complexity IQ Mismatch Compensation Algorithm With Channel Awareness for Two-Path Successive Relay Networks

In this letter, we develop an in-phase and quadrature-phase mismatch compensation algorithm with channel awareness for two-path successive relay networks. Staring from the maximum likelihood criterion, the proposed estimator exploits the a posteriori probabilities provided by the data detector to iteratively improve the estimation process with the aid of an expectation-maximization procedure. The proposed algorithm has many interesting features such as low complexity, accommodating with any soft detector, treating all unknown parameters as a single parameter, and applicability to both uncoded and coded networks. The performance of the proposed algorithm is assessed via Monte Carlo simulations.