Genetic algorithm optimization and realization of broadband loaded wire monopoles

In Yegin (1999) and Yegin and Martin (1997), a monopole antenna is loaded with three parallel inductor-resistor circuits and has an ideal lossless matching network consisting of a transformer, shunt inductors, and series capacitors. Although no measured results are presented, the numerical results indicate voltage standing wave ratio (VSWR) less than 3.5 and system gain greater than -5.5 dBi over a 25:1 bandwidth (20-500 MHz). In this paper, the system of Yegin is simplified and re-optimized over a 15:1 bandwidth in order to pursue a physically realizable design. Measured results of a constructed antenna and matching network indicate a bandwidth ratio of 12.6:1.