System and method for monitoring a respiration rate of an occupant

An ultrasonic sensing system (100) includes an ultrasonic transmitter (106), an ultrasonic receiver (108), a processor (102) and a memory subsystem (104). The transmitter (106) is positioned to transmit an ultrasonic signal into a predetermined volume. The receiver (108) is positioned to receive a composite signal from the predetermined volume. The processor (102) is coupled to the transmitter (106), the receiver (108) and the memory subsystem (104). The memory subsystem (104) stores code that when executed by the processor (102) instructs the processor (102) to perform a number of steps to determine whether an occupant is present in the predetermined volume and whether the detected occupant has a respiration rate.