Improving signal integrity in time domain measurements of antenna boresight fields

Radiated electric field of an antenna, normalized to the asymptotic far field, is investigated as a function of distance. Far fields are extracted from sampled near fields in the boresight direction by minimizing the mean square error between the sampled fields and the fields fitted with a power series in 1/r where r is the distance between the antenna and the field point. Computed results are presented over a range of parameters such as the frequency, and the maximum distance between transmit and receive apertures, by optimizing the number of field samples and their spacing.