外文翻譯----基于混合信號(hào)的數(shù)據(jù)采集卡的虛擬示波器

1、1外文文獻(xiàn)A DAQ card based mixed signal virtual oscmoscopeAbstractComplex signals find many applications in SONAR, RADAR，Echo Location Systems and for studying the resonant frequencies. Digital Storage Oscilloscopcs(DSO) is u

2、sed these days for acquisition and display of routine signals. This instrument, found in every measurement laboratory, though potent in displaying simple periodic waveforms like sinusoids fails when frequency-varying ti

3、me signals are applied, This problem surfaces because the underlying technique of oscilloscope used to trigger the waveform does not acquiesce with complex signals like chirp. Ready solution to this problem is the mixed

4、signal oscilloscope. This is a costly solution and small laboratories cannot afford to have the costly instruments. In this paper, a cost effective DAQ card based mixed signal virtual 0scilloscope is proposed to study th

5、e complex signals. An intelligent technique, Weighted Hamming Distance (WHD) algorithm was used to accurately trigger the complex waveforms. Also for frequency domain analysis, Joint Time Frequency Analysis(JTFA) techniq

6、ues were used. A LabVlEW'TM based virtual instrument was designed and developed with a capability to acquire, display and analyze the triggered signal. The integrated programming language LabVIEWTM was chosen as it o

7、ffers many simple ready to use functions. In a way the proposal offers a cost effective, fast and flexible solution to treat the complex signals. The need to create such solutions is the consequence of costly hardware sy

8、stems. The deficiency of conventional hardware. Scheme for the virtual oscilloscope for complex signals with some real time experimental results are presented in this work.Kevywords: Virtual instrumentation,Chirp signal,

9、Data acquisition,Triggering, Complex signals, JTFA1.IntroductionFor the last two decades there has been a tremendous progress in computer technology. Measurement domain is no longer left unaffected. The way measurements