fir_win (MathScript RT Module Function)
Owning Class: filter design
Requires: MathScript RT Module
Syntax
b = fir_win(n, w)
b = fir_win(n, w, option)
b = fir_win(n, w, window)
b = fir_win(n, w, s)
b = fir_win(n, w, option, window)
b = fir_win(n, w, option, s)
b = fir_win(n, w, option, window, s)
Legacy Name: fir1
Description
Uses the window design method to design a linear phase FIR filter. This function windows the impulse response with a Hamming window by default.
Inputs
| Name | Description | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | Specifies the filter order. n is a nonnegative integer. n must be even for filters with a non-zero gain at the Nyquist frequency. If n does not meet this condition, LabVIEW increases n by 1. | ||||||||||||
| w | Specifies the cutoff frequencies of the filter. w is real scalar or ascending vector with elements between 0 and 1. 1 represents the Nyquist frequency. fir_win generally designs a multiband FIR filter with bands 0<w<w1, w1<w<w2 … wn<w<1. | ||||||||||||
| option | Specifies the type of filter to design. option is a string that accepts the following values.
|
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| window | Specifies the window coefficients. The length of window must equal n + 1. If n is even and the filter has a non-zero gain at the Nyquist frequency, the length of window must equal n + 2. | ||||||||||||
| s | Specifies whether the magnitude of the designed filter is normalized. s is a string that accepts the following values.
|
Outputs
| Name | Description |
|---|---|
| b | Returns the filter coefficients of order n. b is a real vector. |
Examples
N = 5;
W = 0.2;
B = fir_win(N, W, 'low', win_hann2(6))