Differential evolution to synthesize low sidelobe thinned isophoric time‐modulated planar array with increased directivity

Abstract

In this article, a novel method for synthesizing rectangular planar array through thinning and time-modulation is proposed. A new differential evolution based approach that generates a rank based population is adopted to find out the optimum element off position for thinning and ontime duration to modulate the antenna elements in time domain. The proposed synthesis method defines a preservative boundary at the array center where the antenna elements are not thinned and timemodulated rather uniformly excited. It is shown that this proposed thinning and time-modulation strategy with an optimum preservative boundary helps to realize low side lobe radiation pattern with increased directivity by controlling less number of optimization variables as compared to traditional approach. It also reduces the feed network complexity specifically for large antenna arrays. K E Y W O R D S differential evolution, preservative boundary, side lobe level, thinning, time modulation

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