Local Calibration of Antenna Arrays

We consider a local calibration method which does not assume any specific model for the mismatch between the true and assumed array manifolds. The method is based on updating an initial array manifold locally, in the neighborhood of directions in which signals have been observed. The algorithm can handle direction-dependent mismatch and makes use of signals of opportunity whose directions are either known or unknovni. These signals arc observed over multiple data collection periods.