Combined equal and unequal element spacings for low sidelobe pattern of a symmetrical array with equal-amplitude elements

Numerical computations were made for a low-sidelobe-level 20-element symmetrical linear array whose equal-amplitude elements were spaced mostly equally (but some unequally) to yield aperture illumination densities along the array that approximate a truncated Gaussian distribution. It is argued that this design approach of using both equal and unequal interelement spacings and variations from the array analyzed should be investigated for large arrays and optimized for low sidelobe performance. Another design alternative for a large array is to have different size clusters of equally space elements with the intercluster spacings varied to attain desired tapered average illumination densities