Successive‐phase correction calibration method for modulated wideband converter system

Abstract

The modulated wideband converter (MWC) is a sub‐Nyquist sampling system recently proposed for sampling sparse multi‐band signals. However, due to non‐ideal analogue components, transfer‐matrix calibration is required for the successful reconstruction. In practice, it is difficult to control the phases of the consecutive sinusoidal inputs precisely which are used to calibrate the transfer‐matrix. Here, the authors propose a method of transfer‐matrix calibration for the MWC with digital expanded channels when the phases of the sinusoidal inputs are unknown. As the oblique elements of the MWC transfer‐matrix are equal, the authors can estimate the unknown phases first. The authors then obtain the actual transfer‐matrix by phase correction. Finally, the validity of this method is verified by simulation and hardware experiment. The system performance is measured by computing the signal‐to‐noise ratio and the mean‐square error between the original and reconstructed signals.