Sudoku sequences, Costas sequences, and random permutations in a multi-sub-FDA radar

Abstract

Frequency diverse arrays (FDAs), which employ a small frequency increment across each array element, are of recent interest as a popular beam steering technique since they generate a range-angle dependent beampatterns. This paper explores the use of permutations of integers to specify multiples of a transmit frequency offset from carrier for the elements of a multi-sub-FDA, a new architecture in FDA research. The resulting patterns have a peak at a user-specified range and aspect angle, and are periodic in range. Range peak sidelobe ratio (PSLR) and integrated sidelobe level (ISL) analyses with respect to bandwidth reveal the utility of sequences obtained from solved Sudoku puzzles in providing far-field patterns for use in a beacon or for area surveillance.