Diversity Antenna System for Satellite Digital Audio Radio

A diversity antenna system with antennas embedded in rear view mirrors of a vehicle is proposed for satellite digital audio radio system. Antenna diversity is needed because hidden antennas exhibit limited capability and composite body vehicles have poor reception due to no ground plane availability. Pattern gain diversity achieved with the proposed system is proven with on-vehicle antenna simulations and gain measurements. Selection combining diversity receiver architecture is also proposed and the system is tested in real time under two fading scenarios: weak satellite signal in dense foliage and multipath terrestrial environment with frequent satellite blockages. In both cases, the diversity system outperformed the reference antenna system with less mutes times (0.6% versus 0.8% in multipath, 0.1% versus 0.25% in dense foliage) and Reed-Solomon block errors (1.75% versus 2.18% in multipath, 0.87% versus 1.18% in dense foliage). The proposed rear-view mirror location is ideal for minimum signal degradation compared to windshield, backlite, and dashboard antenna installations.