Method and analysis system for determining a state of a diaphragm of an ultrasound sensor

A method for determining a state of a diaphragm of an ultrasound sensor during operation of the ultrasound sensor, the method comprising:

• applying a first excitation signal in a predefined first frequency profile to the diaphragm of the ultrasound sensor;
• measuring a first voltage profile, which is caused by the first excitation signal, as a function of a frequency of the first excitation signal;
• applying a second excitation signal, which has a second frequency profile that differs from the first frequency profile, to the diaphragm of the ultrasound sensor;
• measuring a second voltage profile, which is caused by the second excitation signal, as a function of a frequency of the second excitation signal;
• shifting the first voltage profile by an amount in a first direction and shifting the second voltage profile by the same amount in a second direction, so that respective positions of maxima of the two voltage profiles are matched to each other in a predefined frequency range;
• determining a third voltage profile which runs between the shifted first voltage profile and the shifted second voltage profile;
• and
• determining the state of the diaphragm by comparing the third voltage profile to a predefined reference voltage profile, and/or determining the state of the diaphragm by determining at least one electrical parameter of a model for continuous excitation of the diaphragm and comparing at least one parameter with at least one predefined reference parameter.