Aerosol generator comprising a surface acoustic wave atomiser

An aerosol-generator for an aerosol-generating device, the aerosol-generator comprising:

• a surface acoustic wave atomiser comprising:
• a substrate comprising an active surface defining an atomisation region, and
• a transducer disposed on the active surface of the substrate;
• a supply element arranged to supply a liquid aerosol-forming substrate to the atomisation region;
• and
• a controller configured to:
• operate the transducer as an input transducer to generate surface acoustic waves on the active surface of the substrate,
• operate the transducer as an output transducer to sense surface acoustic waves on the active surface of the substrate,
• receive an output signal from the transducer when the transducer is operated as the output transducer,
• provide an input signal to the transducer when the transducer is operated as an input transducer, and
• vary the input signal to control the input transducer based on the output signal received by the controller from the transducer when the transducer is operated as an output transducer.