The frequency modulation has big advantages compared to the amplitude modulation, even if the amplitude modulation is still used in most of the measurements systems in the common market. The advantage is associated to the fact that the information is not transferred using the height of a tension or of a current, but the number of pulsation (frequency) in a certain time period. As a result it can be less easily disturbed and does not depend on the quality of the cable connection.

Comparison of the amplitude measurement and the frequency measurement