3 * Copyright 2004 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.
23 #ifndef INCLUDED_GRI_LFSR_15_1_0_H
24 #define INCLUDED_GRI_LFSR_15_1_0_H
27 * \brief Linear Feedback Shift Register using primitive polynomial x^15 + x + 1
30 * Generates a maximal length pseudo-random sequence of length 2^15 - 1 bits.
33 class gri_lfsr_15_1_0 {
34 unsigned long d_sr; // shift register
38 gri_lfsr_15_1_0 () { reset (); }
40 void reset () { d_sr = 0x7fff; }
43 d_sr = ((((d_sr >> 1) ^ d_sr) & 0x1) << 14) | (d_sr >> 1);
49 for (int i = 0; i < 8; i++){
58 #endif /* INCLUDED_GRI_LFSR_15_1_0_H */