Criticisms of the Woodward-Lawson method

Abstract

An antenna pattern synthesis technique, applicable to equispaced linear arrays and continuous 1 ine sources, was first introduced by Woodward [l] in 1946 and then elaborated in collaboration with Lawson [21 in 1948. Known as the Woodward-Lawson method, it has been used to synthesize shaped beam patterns. Simply stated, it consists of the superposition of a family of excitations, each with au niform amplitude distribution and a uniform progressive phase distribution. The first partial excitation produces a pattern with a main beam s iadnde lobes that tail off from a level of -13.5 dB; the placement of the main beam is governed by the value of the uniform progressive phase. The second partial excitation does likewise, but its uniform progressive phase is adjusted so that its main beam peak coincides with an innermost null of the first pattern, etc. This scheme results in the filling in of a sequence of nulls in the first pattern; the amount of null-filling i s governed by the relative amplitudes of the partial excitations.