Techniques for developing and realizing a broadband, loaded wire antenna with a transmission line transformer matching network are presented. The component values and position of a parallel inductor-resistor load circuit are optimized via a genetic algorithm to improve the bandwidth of a straight-wire monopole antenna. Candidate antennas are analyzed by solving the electric field integral equation with a lumped-load model included. This model has been enhanced with fast algorithms from the literature in order to improve computational efficiency during optimization. Subsequent to optimization, the curved-wire integral equation solution is used to more closely model a real-world monopole loaded with a helical coil and parallel resistor. The measured input voltage standing wave ratio of the loaded antenna with matching network is below 3.5 over a 5:1 bandwidth (200--1000 MHz). The computed system gain is above -4.0 dBi over the band 220--1000 MHz. ¿ 2001 American Geophysical Union