A system configured to provide respiratory therapy to a subject, the system comprising: a respiratory therapy delivery device configured to deliver breathable gas to an airway of a subject, wherein the respiratory therapy delivery device includes a piezoelectric element and a conduit configured to fluidly couple the piezoelectric element and a subject interface appliance; a sensor configured to generate output signals conveying information related to one or more characteristics of ultrasonic energy emitted by one or both of the respiratory therapy delivery device during operation and/or emitted from the airway of the subject; and one or more processors configured to execute computer program modules, the computer program modules comprising: a parameter determination module configured to determine, based on the generated output signals, a first parameter that indicates energy amplitude of the emitted ultrasonic energy; and a characterization module configured to determine a characterization of the emitted ultrasonic energy, wherein the characterization is based on the first parameter; and wherein the characterization comprises at least one of the group of: - whether ultrasonic energy emitted by the airway of the subject during inhalation is present; - a detection of one or more changes in temperature and/or humidity within the conduit; and - one or more respiratory parameters of the subject, characterized in that the computer program modules further comprise a control module configured to control the respiratory therapy delivery device during operation through an adjustment of the piezoelectric element responsive to the characterization. a respiratory therapy delivery device configured to deliver breathable gas to an airway of a subject, wherein the respiratory therapy delivery device includes a piezoelectric element and a conduit configured to fluidly couple the piezoelectric element and a subject interface appliance; a sensor configured to generate output signals conveying information related to one or more characteristics of ultrasonic energy emitted by one or both of the respiratory therapy delivery device during operation and/or emitted from the airway of the subject; and one or more processors configured to execute computer program modules, the computer program modules comprising: a parameter determination module configured to determine, based on the generated output signals, a first parameter that indicates energy amplitude of the emitted ultrasonic energy; and a characterization module configured to determine a characterization of the emitted ultrasonic energy, wherein the characterization is based on the first parameter; and wherein the characterization comprises at least one of the group of: - whether ultrasonic energy emitted by the airway of the subject during inhalation is present; - a detection of one or more changes in temperature and/or humidity within the conduit; and - one or more respiratory parameters of the subject, a parameter determination module configured to determine, based on the generated output signals, a first parameter that indicates energy amplitude of the emitted ultrasonic energy; and a characterization module configured to determine a characterization of the emitted ultrasonic energy, wherein the characterization is based on the first parameter; and wherein the characterization comprises at least one of the group of: - whether ultrasonic energy emitted by the airway of the subject during inhalation is present; - a detection of one or more changes in temperature and/or humidity within the conduit; and - one or more respiratory parameters of the subject, - whether ultrasonic energy emitted by the airway of the subject during inhalation is present; - a detection of one or more changes in temperature and/or humidity within the conduit; and - one or more respiratory parameters of the subject, characterized in that the computer program modules further comprise a control module configured to control the respiratory therapy delivery device during operation through an adjustment of the piezoelectric element responsive to the characterization.