Ultrasonic DataAcquisition: Signal toNoise Ratio Improvement

Inthis paper an Ultrasonic DataAcquisition Systemanda digital signal processing algorithm inorder toimprove signal tonoise ratio andensuretheenvelope detection arepresented. TheDataAcquisition System isbased on an ADuC812micro-converter anda pairofMA400ST/R ultrasonic transducers. Thereceived dataare transmitted toa hostcomputerviaan RS232serial interface. Thedigital signal processing isperformed inMatlab, and,makesextensive useofthewell knownMovingAverage Filter (MAF)algorithm. MAF are extensively used as low-pass filters dueto their goodsmoothing performance andeaseofimplementation insoftware andhardware as well. In this paper we will demonstrate thatusing thesame MAF algorithm, one can address allthefiltering tasks (low-pass, high-pass, notch), implied bythe processofenvelope detection ofultrasonic echoes.