80GHz Radar Level Meter

Principle

The CPR6400 and CPR6900 series radar level meters use FMCW frequency modulated continuous wave technology for 80 GHz radar level meters. The radar emits a 76-81GHz high-frequency microwave signal with linear frequency modulation, which is emitted from the radar antenna. When the microwave signal encounters the surface of the measured medium, some of its energy is reflected back by the surface of the medium and received by the radar antenna. In radar, a portion of the microwave transmitted signal is mixed with the received signal to obtain the difference frequency signal between the two. The differential frequency signal is obtained by Fourier transform algorithms such as FFT or DFT to obtain the differential frequency spectrum signal, thereby obtaining the frequency difference. According to the linear frequency modulation signal, the frequency difference is proportional to time, thus obtaining the time difference. Based on the time difference and the distance between the antenna and the surface of the measured medium, the distance between the antenna and the surface of the measured medium can be calculated.