An All-Phase-Vector-Fitting-Based Self-Calibration Method for Elemental Digital Phased Array with Distributed Local Oscillators

In this paper, a self-calibration method based on all phase vector fitting for elemental digital phased array with distributed local oscillators is proposed. Firstly, aiming at the problem of the random phase caused by the distributed local oscillators, an elemental digital phased array with distributed local oscillators model is constructed. Then, the third-order fitting curve of the receiver reference power in all phase range is obtained by an external calibration, which is used as a reference to calibrate the transmission channel with random phase by the all phase vector fitting method. Finally, the self-calibration method is verified by using a four-channel elemental digital phased array. Based on this method, the calibrated mean absolute error of the phase difference among the phased array channels is reduced to 3.08°.