3.1 Perception Layer: Multi‑Sensor Iteration and Upgrade, Accelerated Domestic Substitution
The perception layer serves as the "eyes" of intelligent driving. Its core sensors include cameras, ultrasonic radars, millimeter‑wave radars, and LiDAR, each with complementary performance, cost, and application scenarios, together forming a complete environmental perception system.
Ultrasonic radar has the lowest cost—averaging only RMB 28 per unit in 2025—but its detection range is only a few meters and its function is limited; it is currently used solely for reversing assistance.
Cameras offer a balanced cost‑performance ratio and can recognize semantic information such as colors and traffic signs. They are standard hardware for all intelligent driving systems, with an average unit price of about RMB 266 in 2025. Their only drawback is relatively weak perception stability in harsh environments.
Millimeter‑wave radar excels at anti‑interference, unaffected by rain, snow, or fog; it provides high speed measurement accuracy and a detection range of 200‑400 meters. In 2025, the average unit price dropped to RMB 111. Its accuracy is slightly inferior to LiDAR, but high‑end 4D millimeter‑wave radar performs comparably to a 64‑line LiDAR, making it a mainstream blind‑spot supplement sensor.
LiDAR leads the industry in perception accuracy, point cloud density, and detection range. For example, the Hesai ATX LiDAR achieves a point cloud density of 3.84 million points per second, far surpassing the 30,000‑100,000 points per second of 4D millimeter‑wave radar. It can precisely identify small targets and irregular obstacles, meeting the safety redundancy requirements of high‑level autonomous driving. Its drawbacks are relatively high cost and weaker penetration in rain and snow; the average unit price in 2025 was about RMB 1,835.
Currently, the core debate in the perception layer revolves around LiDAR adoption: on one hand, LiDAR costs remain high, prompting mid‑ and low‑end vehicles to adopt "millimeter‑wave radar + camera" solutions without LiDAR for cost control; on the other hand, multi‑sensor fusion algorithms are complex, making it difficult to define priority levels among different hardware data, leading to information conflicts and system misjudgments that require ongoing technical optimization.