On the design of broad-band loaded wire antennas using the simplified real frequency technique and a genetic algorithm

A novel design methodology for broad-band loaded wire antennas is presented that combines the genetic algorithm and the simplified real frequency technique (SRFT) to remove the requirement of choosing the types of load circuits and matching networks a priori. Analytical expressions for the impedance functions of load circuits and matching networks are obtained in the form of rational polynomials via the SRFT. The location of loads on the antenna and the resistance functions of the load circuits and matching networks are optimized using a genetic algorithm. Maximization of system gain in the azimuth and minimization of voltage standing wave ratio are sought as design objectives. The circuit topologies and the component values are automatically arrived at using Darlington synthesis after the optimization process is complete. Also demonstrated, is the use of this procedure to achieve broad-band operation in the HF band for the unloaded and loaded monopoles assuming electronically switched matching networks.