1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
/* -*- c++ -*- */
/*
* Copyright 2004 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* GNU Radio is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Radio; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifndef INCLUDED_GR_REMEZ_H
#define INCLUDED_GR_REMEZ_H
#include <gr_core_api.h>
#include <gr_types.h>
#include <string>
#include <stdexcept>
/*!
* \brief Parks-McClellan FIR filter design.
*
* \ingroup filter_design
*
* Calculates the optimal (in the Chebyshev/minimax sense) FIR filter
* inpulse reponse given a set of band edges, the desired reponse on
* those bands, and the weight given to the error in those bands.
*
* \param order filter order (number of taps in the returned filter - 1)
* \param bands frequency at the band edges [ b1 e1 b2 e2 b3 e3 ...]
* \param ampl desired amplitude at the band edges [ a(b1) a(e1) a(b2) a(e2) ...]
* \param error_weight weighting applied to each band (usually 1)
* \param filter_type one of "bandpass", "hilbert" or "differentiator"
* \param grid_density determines how accurately the filter will be constructed. \
* The minimum value is 16; higher values are slower to compute.
*
* Frequency is in the range [0, 1], with 1 being the Nyquist frequency (Fs/2)
*
* \returns vector of computed taps
*
* \throws std::runtime_error if args are invalid or calculation fails to converge.
*/
GR_CORE_API std::vector<double>
gr_remez (int order,
const std::vector<double> &bands,
const std::vector<double> &l,
const std::vector<double> &error_weight,
const std::string filter_type = "bandpass",
int grid_density = 16
) throw (std::runtime_error);
#endif /* INCLUDED_GR_REMEZ_H */
|
