Optimization of Sparse Frequency Diverse Array With Time-Invariant Spatial-Focusing Beampattern

The optimization of the sparse time-modulated optimized frequency offset frequency diverse array (S-TMOFO-FDA) with time-invariant spatial-focusing beampattern is presented. The minimum array with smallest number of elements is obtained through iterative optimization. From numerical results, the S-TMOFO-FDA can provide above 70% reduction in the element amount while displaying superior sidelobe performance than the same aperture-sized full uniform time-modulated logarithmically increasing frequency offset frequency diverse arrays. Furthermore, the scanning performance of the optimized array is also investigated. The S-TMOFO-FDAs of different array length are optimized.