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143 lines
4.1 KiB
C++
143 lines
4.1 KiB
C++
/* delay.c
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This file is part of a program that implements a Software-Defined Radio.
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Copyright (C) 2013, 2019 Warren Pratt, NR0V
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Copyright (C) 2024 Edouard Griffiths, F4EXB Adapted to SDRangel
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This program is free software; you can redistribute it and/or
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modify it under the terms of the GNU General Public License
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as published by the Free Software Foundation; either version 2
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of the License, or (at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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The author can be reached by email at
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warren@wpratt.com
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*/
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#include "comm.hpp"
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#include "delay.hpp"
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#include "fir.hpp"
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namespace WDSP {
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DELAY* create_delay (int run, int size, float* in, float* out, int rate, float tdelta, float tdelay)
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{
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DELAY *a = new DELAY;
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a->run = run;
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a->size = size;
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a->in = in;
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a->out = out;
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a->rate = rate;
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a->tdelta = tdelta;
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a->tdelay = tdelay;
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a->L = (int)(0.5 + 1.0 / (a->tdelta * (float)a->rate));
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a->adelta = 1.0 / (a->rate * a->L);
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a->ft = 0.45 / (float)a->L;
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a->ncoef = (int)(60.0 / a->ft);
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a->ncoef = (a->ncoef / a->L + 1) * a->L;
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a->cpp = a->ncoef / a->L;
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a->phnum = (int)(0.5 + a->tdelay / a->adelta);
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a->snum = a->phnum / a->L;
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a->phnum %= a->L;
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a->idx_in = 0;
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a->adelay = a->adelta * (a->snum * a->L + a->phnum);
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a->h = FIR::fir_bandpass (a->ncoef,-a->ft, +a->ft, 1.0, 1, 0, (float)a->L);
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a->rsize = a->cpp + (WSDEL - 1);
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a->ring = new float[a->rsize * 2]; // (float *) malloc0 (a->rsize * sizeof (complex));
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return a;
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}
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void DELAY::destroy_delay (DELAY *a)
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{
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delete[] (a->ring);
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delete[] (a->h);
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delete (a);
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}
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void DELAY::flush_delay (DELAY *a)
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{
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std::fill(a->ring, a->ring + a->cpp * 2, 0);
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a->idx_in = 0;
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}
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void DELAY::xdelay (DELAY *a)
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{
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if (a->run)
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{
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int i, j, k, idx, n;
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float Itmp, Qtmp;
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for (i = 0; i < a->size; i++)
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{
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a->ring[2 * a->idx_in + 0] = a->in[2 * i + 0];
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a->ring[2 * a->idx_in + 1] = a->in[2 * i + 1];
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Itmp = 0.0;
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Qtmp = 0.0;
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if ((n = a->idx_in + a->snum) >= a->rsize)
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n -= a->rsize;
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for (j = 0, k = a->L - 1 - a->phnum; j < a->cpp; j++, k+= a->L)
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{
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if ((idx = n + j) >= a->rsize)
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idx -= a->rsize;
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Itmp += a->ring[2 * idx + 0] * a->h[k];
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Qtmp += a->ring[2 * idx + 1] * a->h[k];
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}
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a->out[2 * i + 0] = Itmp;
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a->out[2 * i + 1] = Qtmp;
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if (--a->idx_in < 0)
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a->idx_in = a->rsize - 1;
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}
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}
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else if (a->out != a->in)
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std::copy( a->in, a->in + a->size * 2, a->out);
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}
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/********************************************************************************************************
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* *
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* Properties *
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* *
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********************************************************************************************************/
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void DELAY::SetDelayRun (DELAY *a, int run)
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{
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a->run = run;
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}
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float DELAY::SetDelayValue (DELAY *a, float tdelay)
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{
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float adelay;
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a->tdelay = tdelay;
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a->phnum = (int)(0.5 + a->tdelay / a->adelta);
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a->snum = a->phnum / a->L;
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a->phnum %= a->L;
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a->adelay = a->adelta * (a->snum * a->L + a->phnum);
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adelay = a->adelay;
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return adelay;
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}
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void DELAY::SetDelayBuffs (DELAY *a, int size, float* in, float* out)
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{
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a->size = size;
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a->in = in;
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a->out = out;
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}
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} // namespace WDSP
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