Level measurement with non-contact radar
Free-radiating radar sensors can determine the level of a medium without contact. The so-called FMCW radar measurement method (Frequency Modulated Continous Wave) is used for this purpose. The transmitted signal is modulated between two known frequency values (NivoRadar® 78...79 GHz) and the difference between the transmitted signal and the echo signal is measured. This difference frequency is directly proportional to the transit time and thus to the distance. The level can then be calculated by adjusting the respective vessel height.
Free-radiating radar sensors are used in both bulk solids and liquid applications.