Why radar might save autonomous cars in bad weather

Autonomous vehicles lose perception ability in fog and rain because cameras and lidar degrade. This work integrates 4D imaging radar—which sees through weather via radio waves and motion—into multi-agent perception systems with a Doppler-guided attention mechanism. Two new benchmarks (OPV2V-R, Adver-City-R) with simulated weather allow testing. Results show radar can replace or complement lidar, with major robustness gains in adverse conditions and validation on real truck data.