A low sidelobe level nonequispaced microstrip array antenna design for BTS application using genetic algorithm

Achieving low side lobe level array antennas without implementation of phase shifters or amplitude tapering is a valuable solution in cases, which the simplicity of the structure is of high importance. In this paper a low sidelobe level microstrip array antenna is designed for GSM base-station antenna application using genetic algorithm by variation of the distances between elements around their nominal value. Using only 5 elements, sidelobe levels less than 15 dB are achieved which shows about 2.3 dB improvements regarding the equispaced array. The results are verified using IE3D software and good agreement is observed. The far field patterns are provided for comparison purposes