Presenting a Method for Wide Band Nulling by Spiral Array Antenna

Spiral phased array antenna nulling is presented. The array factor and classic method for spiral array antenna proposed here. Proposed method and genetic algorithm for optimization of fixed nulling in spiral array antenna are used and compared. The goal is to achieve a -20 dB in null over the wide frequency band. Our simulation shows -20 dB over 75 MHz null bandwidth, in VHF band by GA and over 90 MHz null bandwidth by proposed design method.