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Nyquist Frequency

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    283115

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    Note

    The LabVIEW run-time engine needs to be installed on the computer (Windows only), and can be obtained for free from here (user registration required, also free):  http://www.ni.com/download/labview-run-time-engine-2010-sp1/2292/en/

    Simulations themselves can be obtained here:  https://sites.google.com/a/cord.edu/labview-for-analytical-chemistry/

    Run the application called Nyquist.exe.  Set the analog signal frequency to 10 and signal amplitude to 5. Set the Noise Standard Deviation at 0.

    1. Describe the Nyquist Sampling Theorem. Your textbook or other resources on the internet will be helpful for this.

     

     

     

     

    1. Describe what your digitally sampled signal looks like if the sampling frequency is the same as the analog signal frequency.

     

     

     

     

     

    1. Based upon the Nyquist sampling theorem, what is the minimum sampling rate you should use for this analog signal?

     

     

     

     

     

    1. Using the minimum sampling rate, what are the differences between the analog and the digital signals?

     

     

     

     

     

    1. What happens as the sampling rate drops below the Nyquist frequency?

     

     

     

     

     

    1. With no noise on the analog signal, at what sampling frequency does the shape of the digital signal begin to differ significantly from the analog signal?

     

     

     

     

    1. Increase the noise standard deviation from 0 to 1 to 2 to 3. How does the analog signal change as the noise standard deviation increases?  How does your answer to the previous question change?

     

     

     

     

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