Array self calibration: Identifiability issues

Array self calibration consists of identifying array shape distortions and deviations to gain and phase sensor responses, in an unknown source field. Conditions of local identifiability of these parameters are established, and turn out to depend on the type of array and the type of field. The minimal number of sources and sensors is calculated in each case, and the nature of the remaining degrees of freedom is interpreted. With an additional knowledge, that can be provided by a manœuvre or by a perfect sensor, it is shown that the latter parameters can be in turn identified.