Impact of the ground plane topology on the performances of a pyramidal multiband quadri-element antenna

This paper presents investigations performed on the ground plane topology of a pyramidal multiband quadri-element antenna recently introduced mainly for radio navigation applications. The analyses led to a new topology of ground plane that reduces the overall height of the antenna without affecting the electrical performances of the antenna, mainly input matching and radiation patterns. A solution with flat ground plane is also investigated for applications requiring further compactness. Simulations results are presented for the different considered design assuming a frequency plan including radio navigation frequency bands (L1/L5) as well as satellite telemetry frequency band (S-band). Only the lower frequency band is considered as it is the one mostly affected by the ground plane topology.