Abstract: An digital interface and receiver for time-of-flight level measurement and pulse-echo ranging systems. The level measurement device comprises a controller, a transducer, a transmitter stage, an interface, and a digital receive signal processing module. The transmitter is operatively coupled to the transducer and responsive to the controller for emitting energy pulses directed at the surface of a material contained in a vessel. The interface is operatively coupled to the transducer and includes an analog-to-digital converter for digitizing the energy pulses reflected by the surface. The digital receive signal processing module comprises a plurality of program components for processing the digitized echo pulses and determining a level measurement for the material contained in the vessel.

Abstract: A method and apparatus for calibrating and/or improving the accuracy of time of flight ranging or level measurement systems. A correction factor is determined and applied to the calculated receive times for echo pulses in response to a change in the amplitude of the echo pulses or in response to a change in the noise floor.