An antenna pattern measurement technique for eliminating the fields scattered from the edges of a finite ground plane

A novel antenna pattern measurement technique is presented to eliminate the effects of the finite ground plane and anechoic chamber wall reflections which significantly perturb antenna pattern measurements. This technique consists of the measurement of the edge-diffracted fields and their subsequent subtraction from the original pattern. A simple theoretical model is developed to introduce the subtraction technique, and comparisons are made which show the excellent agreement between theoretical (assuming an infinite ground plane) and 'corrected' experimental antenna patterns. Experimental results are given for open-ended waveguide, microstrip patch, and monopole antennas mounted on circular and square ground planes of various sizes. Time gating techniques are illustrated as well.>