Frequency Notched UWB Planar Monopole Antenna Optimization Using a Finite Element Method-Based Approach

The objective of this work is the design and optimization of an ultrawideband (UWB) planar monopole antenna with frequency-notched behavior intended to get rid of the 5-6 GHz frequency band for WLAN compatibility purposes. An optimized profile UWB planar monopole designed by means of a Simulated Annealing algorithm and full three-dimensional finite element method, detailed in a companion paper, was considered as the design starting point. In order to design the band-notched rejection no full finite element analysis is carried out on each profile modification as is usual. The procedure is based on a genetic algorithm and a multipurpose admittance matrix approach instead. Artificial ports are allowed in the computational domain and an admittance-type matrix comes up. As a result, a multiport network describes the electromagnetics within the analysis domain. Circuit manipulations of this network efficiently outperform full-wave analyses for different monopole modifications, thus making it possible to use this strategy in a computer aided-design scheme.