Synthesis of broadside and scanned beam pattern with time modulated antenna array using Artificial Bees Colony algorithm

Abstract

The article describes the application of Artificial Bees Colony algorithm for synthesis of broadside and scanned beam pattern using time modulated linear antenna array. The algorithm is used to obtain the optimum time pulses in order to generate the desired beam pattern at the central frequency while constraining the side band radiation bellow a fixed level. Two instances have been presented: first one synthesizes broad side radiation pattern with fixed sidelobe level (SLL) and first null beam width (FNBW) while second one generates scanned beam pattern steered at different scan angle from broadside with fixed sidelobe level (SLL) and first null beam width (FNBW). Time modulated linear antenna array consisting of 16 elements printed dipoles above a ground plane is simulated. The proposed technique utilizes on-off RF switches and operated at 3GHz central frequency and time switched at 1MHz pulse repetition frequency. Simulated results are in good agreement with those obtained using analytical approaches. Reduction of radiated power at sideband frequencies increases the gain of the proposed array.