What is the difference between the pulse radar method and the FMCW radar method?
A pulse radar sensor sends out a very short pulse which is reflected by the measured product and received back at the antenna. The time between emission and reception, which is proportional to the travelled distance and thus to the filling level in the vessel, is measured. An FMCW radar sensor sends out a continuous frequency-modulated signal. This signal is also reflected by the measured product and received back at the antenna. Because of the time the signal requires to travel the measuring distance, the sensor receives a different frequency than the one it sends out. The difference between these frequencies, which is also proportional to the travelled distance and thus to the level in the vessel, is measured.
