Design of non-uniform linear antenna arrays with digitized spacing and amplitude levels

Recent developments in space exploration have shown a need for high resolution, high gain antennas. The introduction of non-uniform linear array theory has provided a means by which arrays may be designed to produce narrow main beams with fewer elements than required by uniform arrays. A general theory has not been developed, however, and the design engineer has been left with only trial-and-error methods with which to work. In this study a technique has been developed by which non-uniform antenna arrays may be synthesized to meet a given set of specifications with reasonable accuracy. The elements of the array are required to occupy any one of a number of preselected positions, and there may be coincidence of elements as the array is built up. Coincidence corresponds to multiplying the current of a single element by a factor equal to the number of elements found in the position in the completed design. It is seen that this method results in quantized, or digitized, amplitudes and spacing of the elements in the linear array. This method is ideal for solution on a digital computer, where the field pattern may be optimized with respect to any one of several parameters. Several design examples are given, and in general it is found that arrays can be designed, by this method, to have higher directivity, lower sidelobes and fewer elements than uniform linear arrays of the same aperture or with the same number of elements --Abstract, page ii