Array Excitation Error Analysis

The array pattern synthesis requires precise excitation of each antenna element by various synthesis techniques to obtain desired array pattern features, e.g., high directivity, low SLL, and null control. However, the realistic antenna element excitations inevitably differ from their expected values in practice. These errors would cause array pattern distortion, gain degradation, worse SLL, and null drifts [1–3]. Therefore, knowledge about the impacts of the excitation errors and the corresponding calibration methods are of high importance for phased array antennas. Many methods have been proposed to analyze the impacts of excitation errors on array performance. These analysis methods fall into mainly two different types, probabilistic methods and interval arithmetic (IA) based methods, which are presented in the following two subsections.