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Acoustic-pulse compression is obtained in systems with differenttimebandwidth products by applying the digital matched-filter technique toultrasonic non-destructive testing.The signal is linearly frequency-modulated(LFM)pulse and the digitized electrical-excitation signalitself is used as a digita1 matched filter.Experimental results are in goodagreement with theory.Suppressions of side lobes achieve -41.9 dB and-41.5 dB for the Hamming and Gaussian weighted signals respectively.It shows that the application of the digital matched-filter technique im-proves the performances of a ultrasonic testing system explicitly.
Acoustic-pulse compression is obtained in systems with differenttimebandwidth products by applying the digital matched-filter technique toultrasonic non-destructive testing. Signal is linearly frequency-modulated (LFM) pulse and the digitized electrical-excitation signalitself is used as a digita1 matched filter . Experimental results are in good agreement with theory. Aspect count of side lobes achieve -41.9 dB and -41.5 dB for the Hamming and Gaussian weighted signals respectively. It shows that the application of the digital matched-filter technique im-proves the performances of an ultrasonic testing system explicitly.