An aperture-coupled circularly polarized stacked microstrip antenna for GPS frequency bands L1, L2, and L5

This paper has investigated the technique of stacking microstrip antennas to achieve dual frequency operation for GPS frequencies L1 and L2/L5. The coupling between the two patches is dependent on the relative size of the patches and also whether the top patch is smaller or larger than the bottom patch. The relative patch sizes must be adjusted for proper impedance match. The design of this antenna was a tedious process and required numerous empirical tunings due to the number of interacting parameters. The designed antenna is currently under fabrication and measured results will be provided during the presentation.