Explicit Calibration of mmWave Phased Arrays with Phase Dependent Errors

Abstract: We consider an error model for phased array with gain errors and phase errors, with errors dependent on the phase applied and the antenna index. Under this model, we propose an algorithm for measuring the errors by selectively turning on the antennas at specific phases and measuring the transmitted power. In our algorithm, the antennas are turned on individually and then pairwise for the measurements, and rotation of the phased array is not required. We give numerical results to measure the accuracy of the algorithm as a function of the signal-to-noise ratio in the measurement setup. We also compare the performance of our algorithm with the traditional rotating electric vector (REV) method and observe the superiority of our algorithm. Simulations also demonstrate an improvement in the coverage on comparing the cumulative distribution function (CDF) of equivalent isotropically radiated power (EIRP) before and after calibration.