Matrix method for near-field diagnostic techniques of phased arrays

Near-field measurements can be used as diagnostic tools to reconstruct the aperture field distribution of planar array antennas and to locate their possible defective elements. A method for obtaining the individual element excitation of an array antenna from measured near-fields is presented. A computer simulation is performed to evaluate the effect of various near-field parameters such as the measurement distance and the sample spacing on the reconstruction of the excitation. The validity of the approach has been verified using both synthetic and actual measurements data. Good results have been obtained.