Synthesis of non-uniformly spaced arrays using the Fourier transform and window techniques

Under the Fourier relation between the array factor and its corresponding source distribution, synthesis approaches of non-uniformly spaced arrays (NUSAs) are proposed. Using the Fourier transform and synthesis concepts of space-tapered arrays, the optimum patterns like Chebyshev are used to synthesise NUSAs with uniform amplitude, whose array factors have the performance approximated to the chosen patterns. The Fourier transform properties can be used to control the array factor so that the proposed approaches are applied in different synthesis specifications. Based on the synthesised NUSAs with uniform amplitude and window techniques, under the sampling theorem, NUSAs with non-uniform amplitude can be easily obtained to improve the performance of the array factor, mainly in the reduction of sidelobe level. Synthesis examples show the advantages of the presented methods.