An Antenna Diversity and Combining System for Improved Mobile GNSS Reception

A new GNSS diversity system for L1 band is presented which enables beamforming and other forms of GNSS antenna signal combination. The system consists of two antenna structures providing three decorrelated antenna ports, which are connected to a three-way phase shifting and switching module. A combiner merges all paths to one RF signal, which enables the connection to every customary GNSS receiver. Fields of application are given especially in high precision navigation for example in difficult receiving scenarios. The diversity system enables to reduce or avoid disturbing reflected and diffracted signals and can avoid adverse receiving conditions by steering the antennas combination pattern. Measurement results of a first hardware demonstrator are presented, proving the ability of the antenna diversity system to cancel out reflection paths while maintaining the omnidirectional reception of all the line of sight satellite signals.