h = cl2bp (m, w1, w2, up, lo) ¶h = cl2bp (m, w1, w2, up, lo, gridsize) ¶Constrained L2 bandpass FIR filter design. This is a fast implementation of the algorithm cited below. Compared to remez, it offers implicit specification of transition bands, a higher likelihood of convergence, and an error criterion combining features of both L2 and Chebyshev approaches.
Inputs:
degree of cosine polynomial, i.e. the number of output coefficients will be m*2+1
bandpass filter cutoffs in the range 0 <= w1 < w2 <= pi, where pi is the Nyquist frequency
vector of 3 upper bounds for [stopband1, passband, stopband2]
vector of 3 lower bounds for [stopband1, passband, stopband2]
search grid size; larger values may improve accuracy, but greatly increase calculation time. Default value is 2048, max value is 1e6.
Output:
A vector of m*2+1 FIR coefficients, or an empty value if the solver failed to converge.
Example:
h = cl2bp(30, 0.3*pi, 0.6*pi, [0.02, 1.02, 0.02], [-0.02, 0.98, -0.02], 2^11);
Original Paper: I. W. Selesnick, M. Lang, and C. S. Burrus. A modified algorithm for constrained least square design of multiband FIR filters without specified transition bands. IEEE Trans. on Signal Processing, 46(2):497-501, February 1998.
See also: remez.
Package: signal