Spherical modal filtering of antenna patterns augmented by translation of coordinate origin

This paper describes a novel method termed the Isofilter™ Technique, of isolating the radiation pattern of an individual radiator from among a composite set of radiators that form a complex radiation distribution. This technique proceeds via three successive steps: A spherical transform on an over-sampled data set, followed by a change of coordinate system followed in turn by filtering in the domain of the spherical modes to isolate a radiating source. The result is an approximate pattern of the individual radiator largely uncontaminated by the other competing sources of radiation.