Design of a CPW-fed notched planar monopole antenna for multiband operations using a genetic algorithm

A CPW-fed notched planar monopole antenna is designed for multiband operations using a genetic algorithm (GA) in conjunction with the method of moments (MoM). By introducing a suitable notch to a rectangular CPW-fed patch, the desired multi-frequency resonant modes and broad impedance bandwidths can be obtained. The use of a GA enabled the dimensions of the CPW-fed notched patch structure to be changed at will as optimum impedance matching at the selected bands was sought. Prototypes of the proposed GA-optimised design were constructed and studied experimentally. The measured results of the resulting antenna not only explore good multiband operations with 10 dB impedance bandwidths of 15.3%, 16.6% and 18% at the design bands of 2.42, 3.61 and 5.28 GHz, respectively, but also show good agreement with the numerical prediction. Additionally, details of the physical GA implementation for the optimised configuration are presented and discussed.