The difference between lidar and millimeter wave radar

In simple terms, laser radar mainly detects the surrounding environment by emitting a laser beam. Vehicle laser radar generally uses multiple laser emitters and receivers to establish a three-dimensional point cloud image to achieve real-time environment sensing.
The advantage of LiDAR is that it has a wider detection range and higher detection accuracy. However, Lidar also has disadvantages: poor performance in extreme weather such as rain, snow and fog.
Millimeter wave radar refers to the radar with the working frequency band in the millimeter wave band. The principle of ranging is the same as that of the general radar, that is, the radio wave (radar wave) is sent out, and then the echo is received, and the target is measured according to the time difference between the transmitting and receiving. Location data. The millimeter wave radar is the frequency of this radio wave is the millimeter wave band.
The wavelength of the millimeter wave is between the centimeter wave and the light wave, so the millimeter wave has the advantages of microwave guidance and photoelectric guidance, and the guide head has the characteristics of small volume, light weight and high spatial resolution. In addition, the millimeter wave seeker has a strong ability to penetrate fog, smoke, and dust, which is a big advantage over laser radar.
The shortcomings of millimeter-wave radar are also very intuitive. The detection range is directly constrained by the band loss (high-band radar must be used to detect the far-reaching), and pedestrians cannot be perceived, and all obstacles around can not be accurately modeled.