Method of null steering without using phase shifters

Abstract

Null steering without using phase shifters is achieved by forcing the zeros of the array factor to occur in conjugate pairs on the unit circle in the complex plane. It is shown that if the number of jammers is much smaller than half the total number of elements in the array, it is possible to optimise the pattern as well as suppressing the jammers. Alternatively, wide nulls in the radiation pattern can be easily approximated.