A Compact All-Band Spacecraft Antenna with Stable Gain for Multi-Band GNSS Applications

This study presents a compact and stable gain spacecraft antenna that operates in all Global Navigation Satellite System (GNSS) bands from 1.164 GHz to 1.610 GHz. The proposed antenna structure based on the single-feed crossed bowtie antenna concept consists of four triangular patches excited with a 90° phase difference in between to generate right-hand circular polarization (RHCP), without needing complex feed networks. The radiator part of the antenna is covered by a radome and is also supported by a cylindrical dielectric cavity frame (DCF) to weaken the diffracted waves propagating along the ground plane while increasing vibration resistance. The fabricated antenna provides a return loss better than 10 dB with lower than 3 dB axial ratio and a stable gain around 7.2 ± 0.3 dBic over the entire GNSS bands, as well as a more compact and lightweight structural performance. It is also verified that the structural integrity and functional performance of the fabricated antenna remain consistent despite exposure to an equivalent vibration level in the launch process. The presented all-band spacecraft GNSS antenna is an innovative implementation with space industry insight for multi-band space applications that have application-specific limitations and provides consistent performance, as well as operational safety with the antenna design simplicity.