A method to measure the aperture field and experimentally determine the near-field phase center of a horn antenna

A method whereby the aperture field distribution of a horn antenna can be measured is proposed. The method is based on the measurement of the scattered field of a small conducting sphere in the aperture. The position of the phase center of the aperture field is calculated using the measured phase distribution of the field in the aperture via a simple type of convolution. In principle, the method is suited to determine the field distribution of other types of apertures illuminated by an electromagnetic field.<
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