Grating-lobe suppression in phased arrays by subarray rotation

A method of suppressing grating lobes in a uniform planar array is presented. In this method, the array is divided into equal sub-arrays which are physically rotated with respect to each other by specified angles. As a result, the grating lobes, which remain at the same angular distance from the main beam, are multiplied in number by the number of subarrays while their amplitude is divided by the same number. Spacing within each subarray still remains uniform. Only at the subarray boundaries do different spacings occur.