Augmented Hammerstein model for six-port-based wireless receiver calibration
An augmented Hammerstein model (AHM) is proposed for the first time to calibrate a six-port-based receiver (SPR) and to recover the in-phase I and the quadrature Q components of a modulated wideband RF signal. The proposed model is intended to provide a good compromise between complexity and accuracy. To verify the performance of the resulting calibration approach, an experimental validation has been performed with an SPR driven by wideband modulated signals with different bandwidths. An error vector magnitude between the transmitted and received signals of 2.17 and 1.33% has been reported for 64-QAM signals with 4 and 2 MHz bandwidths, respectively. The obtained measurement results have revealed the robustness and the superiority of the AHM-based single-step calibration technique compared with the two-step conventional procedure. Moreover, the AHM achieved the same performance as the published memory polynomial model while requiring ∼60% less coefficients leading to a less complexity calibration procedure with a lower number of calibration parameters and flops.
