CHARACTERISING SYSTEMS FOR RESPIRATORY THERAPY

Apparatus and methods provide system characterisation such as for operation of respiratory treatment apparatus. Such a characterisation may include a determination of a patient interface type and/or an event such as a leak or blocked vent. For a characterisation, one or more controller(s) or processor(s) may be configured to make a determination of parameters that best fit a template curve, such as a quadratic function, to a plurality of measurements, such as data points. Each data point may include a pressure value, and a flow rate value at the pressure value. Parameters from the function may then be applied, such as with a data structure to characterize the system, such as with an identification of the patient interface type from the parameters. In some versions, parameter(s) of operation of the apparatus may be adjusted based on the characterisation, such as by using the parameters of the template.