Impact of Radiation Pattern of GNSS Receiver Patch Antenna in positioning during high rotation rate & Mitigation Techniques

Global Navigation Satellite System (GNSS) receivers are used in launch vehicles for aiding inertial navigation systems for improving the navigation accuracy. In satellites, they are used for finding the precise location of the spacecraft as well as for time based commanding. In a GNSS receiver system, configuration of antenna system along with antenna pattern and RF front-end configuration has a direct impact on visibility of GNSS satellites during different phases of the mission, especially under rotation dynamics. Internationally, the high dynamics capability of a GNSS receiver is specified in terms of linear dynamics. In this paper, an analysis on impact of antenna radiation pattern of a GNSS receiver under high rotation rate is studied. Different body rotation rates are simulated using a GNSS RF Signal Simulator and the performance of GNSS receiver antenna pattern in the two antenna configuration is studied in detail. Analysis of the flight performance of GNSS receiver system in orbital platform experiment under rotation rates is also highlighted in this paper. Limitation w.r.t two antenna configuration with single RF front-end is also discussed and a novel mitigation technique for the above problem using dual RF front-end configuration is also proposed.