Galileo Antenna Gain Pattern Estimation for Signal Quality Monitoring

Abstract

The use of GNSS in safety critical applications imposes stringent requirements in terms of signal quality and integrity. A central element of the GNSS signal quality evaluation is the verification of the available power levels at user location. Given that the state of the GNSS satellite antenna may suffer some level of degradation due to the heavy strains during launch and space environment factors, its nominal performance may be affected, leading to possible anomalies in the radiated signal power. An analysis and evaluation of the GNSS signal quality requires the investigation of such anomalies. This paper describes the methodology and tests performed for GNSS satellite antenna gain pattern estimation for signal quality monitoring. As an example, the methodology is applied for the Galileo system. The obtained results suggest the feasibility of estimating satellite antenna gain patterns using observations from a measurement setup of reduced complexity (e.g. without high-gain antennas). These proof-of-concept tests help to pave the way for further implementation of a signal quality monitoring facility, which can significantly support safety critical applications in future. In addition, the presented methodology may be of interest for remote sensing applications based on GNSS reflectometry.