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Raisied Cosine FIR Filter Function
 Syntax `h = srrcfir(`Nsampsym, Ntaps, beta, KaiserFactor`)` Include: `include spt\srrcfir.oms` See Also pwlfir , pbfir , hilbert , linfir , rcfir
``` ARGUMENTS:   INPUTS:     Nsampsym     = Number of samples per symbol.     Ntaps        = Number of filter taps, >= 2.     beta         = Excess bandwidth, 0 <= beta <= 1.0     KaiserFactor = Kaiser window factor, 2 < K < 20.                    If this is out-of-range, no window is applied.   OUTPUTS:     h = column vector of filter coefficients. Peak sample is 1.0.   RETURN: VECTOR, DOUBLE, filter coefficients. ```
Description ``` ```This function creates a Square-Root Raised Cosine FIR filter, commonly used as a pulse-shaping fiter in digital communication signal generation. This is the filter that would typically be used once in a transmitter and once in a receiver to achieve an overall rasied cosine response. ``` ```"Nsampsym" is the number of samples per symbol resolution of the filter. "Ntaps" is the length of the desired FIR and can be either odd or even. ``` ```"beta" is the excess bandwidth for the FIR (sometimes called "alpha") and is between 0.0 and 1.0. ``` ```The "KaiserFactor" is the adjustment factor for a Kaiser window that may be applied to the FIR during design for sideband suppression. If no windowing is desired, set this any value outside it's range of 2 to 20, 0(zero) for example. ``` ```The function returns a column vector, double precision, of row length "Ntaps". ``` ```Example
Create a 33-tap raised cosine FIR and plot the impulse and frequency responses. ``` Nsampsym     = 4; Nspan        = 8; Ntaps        = Nsampsym*Nspan+1;    # Number of taps beta         = 0.25d0; KaiserFactor = 2d0; h            = srrcfir(Nsampsym, Ntaps, beta, KaiserFactor); ``` ``` ```