Broadband monopole/ dipole antenna with parallel inductor-resistor load circuits and matching networks

Shawn D. Rogers
Chalmers M. Butler
Anthony Q. Martin

Document Type Patent


A broadband loaded antenna and matching network with related methods for design optimization are disclosed. The loaded antenna structures may preferably be either monopole or dipole antennas, but the particular methods and techniques presented herein may be applied to additional antenna configurations. The load circuits positioned along an antenna may comprise parallel inductor-resistor configurations or other combinations of passive circuit elements. A matching network for connecting an antenna to a transmission line or other medium preferably includes at least a transmission line transformer and a parallel inductor. Various optimization techniques are presented to optimize the design of such broadband monopole antennas. These techniques include implementation of simple genetic algorithms (GAs) or micro-GAs. Component modeling for selected components may be effected through either lumped element representation or curved wire representation. Measured results are presented to ensure that certain design criteria are met, including low voltage standing wave ratio (VSWR) and high gain over a desired frequency band.