Impact of Quantization Noise on the Quality of Ultrasonic Signal Deconvolution
In materials characterization, a material’s transfer function is calculated from experimental data. Sometimes, the transfer function of the measurement device, such as an ultrasonic transducer, must be known for this calculation. One of the common methods of obtaining a material transfer function is to measure an elastic waveform before and after it propagates through a material. Then, the transfer function is calculated by deconvolving the two waveforms. We illustrate this process in Fig. 1, where two transducers are placed with a section of plate material between them. The material transfer function is measured by deconvolving the signal at the first transducer from the signal at the second identical transducer. Ideally, this deconvolution would remove the transducer effects. Likewise, if the transducers were placed at the same location (d=0), the transfer function of one transducer could be calculated using a reference transducer.
KeywordsTransfer Function Discrete Fourier Transform Quantization Noise Digital Storage Oscilloscope Dynamic Range Signal
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