Sensor

A method of measuring temperature and/or pressure of a fluid, comprising:

• applying an electrical excitation signal to at least one transducer operable to convert the electrical excitation signal into an acoustic signal in an acoustic resonator for containing a fluid, to establish standing acoustic waves in the acoustic resonator;
• receiving an electrical response signal from at least one transducer operable to convert the acoustic signal in the acoustic resonator into an electrical response signal;
• processing the electrical excitation signal and the electrical response signal to determine an acoustic signal response;
• and
• determining one or more of a pressure and a temperature of the fluid in the acoustic resonator from the acoustic signal response.

A sensor, comprising:

• a resonator unit, the resonator unit comprising an acoustic resonator for containing a fluid, the acoustic resonator being operable to support standing acoustic waves, the resonator unit being operable to convert an electrical excitation signal into an acoustic signal in the acoustic resonator to establish the standing acoustic waves and operable to convert the acoustic signal in the acoustic resonator into an electrical response signal;
• and
• an electronic unit coupled to provide the electrical excitation signal to the resonator unit and to receive the electrical response signal from the resonator unit, the electronic unit comprising a processor and a memory containing instructions executable by the processor to:
• process the electrical excitation signal and the electrical response signal to determine an acoustic signal response;
• and
• determine one or more of a pressure and a temperature of the fluid in the acoustic resonator from the acoustic signal response.