US Patent 8464583 Ultrasonic level measurement apparatus and method having variable transmit power

The invention provides a method for improving the accuracy of level measurement by reducing or eliminating receive circuit saturation in ultrasound level measurement apparatus. The method involves adjusting the transmit power in order to control echo amplitude, in particular to avoid saturation, when the surface being monitored is within a pre-defined distance from the ultrasound transducer. The particular advantage of the invention is that it may be implemented without change to the electronic circuitry embodied in the apparatus.