Patent ID: 8583387

Claim:
An ultrasonic sensing system comprising: an ultrasonic sensor including a microcontroller, a transducer electrically connected to the microcontroller and configured to generate an ultrasonic signal and to receive a reflection of the ultrasonic signal from a surface of a fluid, and a driver electrically connected to the microcontroller and configured to output a pulse-width modulated (PWM) signal based on the reflection, the PWM signal including: a period, and a plurality of pulses including a first pulse having a first pulse width, and encoding a first predetermined parameter based on the first pulse width and a second pulse, having a second pulse width, and encoding a second predetermined parameter based on the second pulse width, the second predetermined parameter different from the first predetermined parameter; and a processor configured to receive the PWM signal from the driver and perform a diagnostic assessment of the ultrasonic sensor based on the period of the PWM signal and the widths of the plurality of pulses of the PWM signal.