3 * Copyright 2006 Free Software Foundation, Inc.
5 * This file is part of GNU Radio
7 * GNU Radio is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 3, or (at your option)
12 * GNU Radio is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with GNU Radio; see the file COPYING. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street,
20 * Boston, MA 02110-1301, USA.
27 #include <gr_constellation_decoder_cb.h>
28 #include <gr_io_signature.h>
36 static const bool compute_EVM = false;
38 gr_constellation_decoder_cb_sptr
39 gr_make_constellation_decoder_cb (const std::vector<gr_complex> &sym_position,
40 const std::vector<unsigned char> &sym_value_out)
42 return gr_constellation_decoder_cb_sptr
43 (new gr_constellation_decoder_cb(sym_position, sym_value_out));
46 gr_constellation_decoder_cb::
47 gr_constellation_decoder_cb (const std::vector<gr_complex> &sym_position,
48 const std::vector<unsigned char> &sym_value_out)
49 : gr_sync_block ("constellation_decoder_cb",
50 gr_make_io_signature (1, 1, sizeof (gr_complex)),
51 gr_make_io_signature (1, 1, sizeof (unsigned char)))
53 if (!set_constellation(sym_position,sym_value_out))
54 throw std::invalid_argument("constellation_decoder_cb");
58 gr_constellation_decoder_cb::~gr_constellation_decoder_cb(){}
62 gr_constellation_decoder_cb::set_constellation(const std::vector<gr_complex> &sym_position,
63 const std::vector<unsigned char> &sym_value_out)
65 if (sym_position.size() != sym_value_out.size())
68 if (sym_position.size()<1)
71 d_sym_position = sym_position;
72 d_sym_value_out = sym_value_out;
78 gr_constellation_decoder_cb::work(int noutput_items,
79 gr_vector_const_void_star &input_items,
80 gr_vector_void_star &output_items)
82 gr_complex const *in = (const gr_complex *) input_items[0];
83 unsigned char *out = (unsigned char *) output_items[0];
84 unsigned int table_size = d_sym_value_out.size();
85 unsigned int min_index = 0;
86 float min_euclid_dist = 0;
87 float euclid_dist = 0;
88 double total_error = 0;
90 for(int i = 0; i < noutput_items; i++){
91 min_euclid_dist = norm(in[i] - d_sym_position[0]);
93 for (unsigned int j = 1; j < table_size; j++){
94 euclid_dist = norm(in[i] - d_sym_position[j]);
95 if (euclid_dist < min_euclid_dist){
96 min_euclid_dist = euclid_dist;
101 out[i] = d_sym_value_out[min_index];
104 total_error += sqrtf(min_euclid_dist);
108 double mean = total_error / noutput_items;
109 double rms = sqrt(mean * mean);
110 fprintf(stderr, "EVM = %8.4f\n", rms);
113 return noutput_items;