The 2RC Filter
Abstract
The 2RC filter was the earliest filter used in surface texture filtering. We introduce the time domain and frequency domain representation and show how these may be plotted in MATLAB. We describe how the 2RC weighting function in the time domain is really a high pass filter, although weighting functions in general are averaging filters and therefore low-pass filters. For the more interested reader, we derive the 2RC weighting function equation from first principles. This derivation also leads to a weighting function equation for the 2RC low-pass filter. We consider an example profile and filter it using both the Gaussian and 2RC filters to illustrate the different amplitude and phase transmission characteristics of the two filters.
Keywords
Transfer Function Weighting Function Voltage Signal Transmission Characteristic Amplitude TransmissionPreview
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References
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