Performance Assessment of a Smart GNSS Antenna Array with Digital Beamforming Supported by a FPGA Platform

New positioning solutions are a key factor in the pursuit of autonomous driving. GNSS is the most common method, however traditional systems may have high position errors due to multipath signals. In this work, we present a GNSS adaptive antenna with beamforming capabilities that can apply spatial filtering to mitigate interferences and improve satellite connectivity, reducing the positioning error. The array, developed with off-the-shelf GNSS antennas, was used to demonstrate the improvement of the gain, leading to better signal to noise ratio, comparatively to the traditional GNSS antenna, while maintaining circular polarization in all directions. A digital beamforming solution was employed with the software defined platform based on a Xilinx ZCU216. The full system performance was tested in an anechoic chamber, where good results were obtained in both single and multibeam scenarios, with great agreement between the simulated and measured data. The results presented in this paper validate the proposed FPGA-based array and beamforming development platform, paving the way for the seamless and rapid design and test of numerous antenna array geometries with up to 16 channels and beamforming algorithms, including adaptive ones. This powerful and versatile tool will accelerate research on performance improvement of GNSS reception.