With the breakthrough of devices and signal processing technology, lidar technology will change from intensity? Modulation, AM) to FM (frequency? Modulation (FM) evolution. FMCW lidar combines radar signal processing technology with laser modulation and demodulation technology instead of simply timing laser pulses, thus solving the problems of poor anti-interference ability and low detection dimension of traditional TOF lidar (traditional lidar lacks Doppler image detection ability compared with microwave radar). Reflected in the application: 1, completely solve the security risks such as sunlight interference, malicious interference and crosstalk between laser radars. 2. Able to work in bad weather, such as rain and dust. Moving targets 3.200 meters away can be detected in real time with a few points (multi-frame images of the camera cannot). The motion information of the target can be used to distinguish the sensitivity of the target and predict the direction of the target, which has a revolutionary impact on the target perception and ranking ability of autonomous driving.
Compared with millimeter wave, FMCW lidar works on the laser carrier, and its imaging effect and target reflection characteristics are closer to the human eye recognition effect, and it will not be interfered by roadside metal objects (parked cars, metal trash cans, building corners) in the working process.
4D released by Guangshao Technology? Coherent Doppler lidar SH2 100 adopts patented coded modulation and homodyne demodulation technology, which avoids the dependence on the modulation linearity of laser light source, greatly reduces the complexity of the system and improves the stability. On the road test effect, SH2 100 reveals its revolutionary effect in the field of automatic driving from the perspective of Doppler, and solves the problem of traditional sensing technology to identify "illegal" moving targets in complex scenes. The following figure is a Doppler point cloud image of SH2 100, in which different colors are used to represent moving targets with different vector speeds.
Below -a (camera effect), the red circle area in the picture is two retrograde motorcycles. In the scene, due to the long distance of motorcycles (100m) and the interference of silver cars and roadside debris (trees, lampposts and bicycles), the traditional technology cannot effectively identify two retrograde objects. Below -b, the 4D Doppler image obtained at the same time of SH2 100 clearly captures two "green" moving targets (Doppler blue shift) in the laser Doppler dimension.
The following figure -c shows the camera imaging effect when the retrograde target approaches the radar equipment (10m). Due to the obstruction of the taxi, the camera image or millimeter wave can no longer find the retrograde motorcycle hidden behind the taxi. SH2 100 has the ability of full echo target Doppler detection, and the emitted laser penetrates the taxi window glass to obtain the distance and Doppler image of the target, which revolutionizes the ability of automatic driving moving target recognition and classification.
Because FMCW lidar has unique imaging effect (with dual detection advantages of millimeter wave and laser) and extremely high technical threshold, it is a revolutionary technology in the field of automatic driving, so FMCW lidar has become a "royal product" of several major manufacturers, and few products can be used and sold publicly. SH2 100 of Guangshao Technology? 4D coherent Doppler lidar made its debut at CES in 2020. In order to promote the rapid development of autonomous driving, Guangshao Technology will provide sample car trial and free Doppler road test data to the majority of autonomous driving companies and automobile manufacturers in 2020Q 1, and will deliver the first batch of SH2 100 products to users in Q3-Q4.
This article comes from car home, the author of the car manufacturer, and does not represent car home's position.