Evaluation of an Uncertainty-Aware Late Fusion Algorithm for Multi-Source Bird's Eye View Detections Under Controlled Noise
Evaluating multi-sensor bird’s-eye view (BEV) detection fusion performance independently of detector errors remains challenging. To address this, we propose a noise-controllable, systematic evaluation framework and design UniKF—a Kalman filter-based, uncertainty-aware unified post-fusion algorithm. Our framework decouples detector errors from fusion performance via controlled noise injection into BEV feature maps or detections. UniKF explicitly models sensor-specific uncertainties (e.g., calibration and measurement noise) and temporal synchronization offsets, enabling robust cross-sensor fusion under realistic conditions. Experiments across varying noise levels demonstrate that UniKF reduces localization and orientation errors by approximately 3× and size estimation error by 2×, while maintaining near-perfect detection accuracy (99.5%–100% precision and recall). These results significantly outperform state-of-the-art fusion methods, validating both the efficacy of our evaluation framework and the robustness of UniKF under uncertainty.