DC component remover
Syntax
Hd = dcremover (Fc, DFormat)
Description
Implements a first order IIR highpass filter (DC component remover), defined in general as:
\(\displaystyle H(z)=G\times\Big(\frac{1-z^{-1}}{1-\alpha z^{-1}}\Big)\)
Defining this alpha filter in terms of a cut-off frequency, \(w_c\),
\(\displaystyle H(z)=\frac{1}{w_c+1} \bigg( \frac{1-z^{-1}} {1+\frac{w_c-1}{w_c+1} z^{-1}} \bigg) = \frac{1-z^{-1}}{(w_c+1)+(w_c-1)z^{-1}}\)
Fc: -3dB cut-off frequency, given by: \(w_c = \tan (\frac{\pi F _c}{f s}) \)
DFormat: allows you to specify the display format of resulting digital filter object.
symbolic |
Display a symbolic representation of the filter object. |
numeric |
Display a matrix representation of the filter object |
void |
Create a filter object, but do not display output |
Example
[code language=”java”]ClearH1; // clear primary filter from cascade
ShowH2DM; // show DM on chart
Main()
F=5;
Hd=dcremover(Fc,”symbolic”);
Num = getnum(Hd); // define numerator coefficients
Den = getden(Hd); // define denominator coefficients
Gain = getgain(Hd); // define gain
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See also
bessel / butter / cheby1 / cheby2 / ellip / arbmagphase / cplxfreqshift / dcremover / notch / peaking