Synthesis of randomly spaced planar antenna array with low peak side lobe level (PSLL) using Modified Genetic Algorithm

Abstract

An optimization technique for the synthesis of randomly spaced planar antenna (RSPA) array with reduced peak side lobe levels is proposed in this paper. Authors assumed two constraints during the synthesis process: the first is to maintain constant amplitude excitation across the entire array elements and the second one is to vary the inter-element spacing randomly within 0.5λ-1.5λ. A Modified Genetic Algorithm (M- GA) is devised in the present study to find the most optimum arrangement of inter-element spacings corresponding to the radiation pattern with low peak side lobe level (PSLL). To authenticate the efficacy of the proposed technique, an 8×12- element RSPA array is considered as an example and analyzed for its performance. The numerical results obtained through the proposed method are compared with that of an array of equal dimension and with uniform inter-element spacing. The PSLL in both azimuth and elevation planes of synthesized RSPA array is much lower than that uniformly spaced planar antenna (USPA) array.