Robustness evaluation of software customized intelligent techniques for oscilloscopes triggering

This paper addresses the problem of time period measurement of complex waveforms using the algorithms, which utilizes the associative memory network based weighted hamming distance (whd) technique and autocorrelation based techniques for noiseless and noisy waveforms. In this work, robustness of both the advance techniques, have been evaluated by simulated addition of random noise to a test complex signal waveform. Here, Complex test waveforms are generated using LabVIEW® software and samples of the test waveforms are captured and stored in as real time test vectors using a PCI-6221 data acquisition card; and these captured test vectors are used for the robustness evaluation. For robustness evaluation, period measurement algorithms are implemented using Matlab®. The mean of minimum value of whd and peak value of coefficient of correlation are computed over 10000 cycles of the selected test waveform, with noise of various levels introduced in the test signal. From the results, it is found that both the techniques are capable of producing trigger pulses efficiently; that results into stable display of the selected complex test waveform even in the presence of noise. Correlation based technique is found to be slightly better from robustness point of view.

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