Hamlib/gnuradio/demod.h

153 wiersze
4.3 KiB
C++

/*
* Hamlib GNUradio backend - Demodulator chain class
* Copyright (c) 2003-2004 by Stephane Fillod
*
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifndef _DEMOD_H
#define _DEMOD_H 1
#include <VrSigProc.h>
#include <GrFreqXlatingFIRfilterCCF.h>
#include <GrFIRfilterFFF.h>
#include <VrAmp.h>
//#include <GrAGC.h>
#include <HrAGC.h>
#include <gr_firdes.h>
#include <gr_fir_builderF.h>
#include "hamlib/rig.h"
#include "misc.h"
#define d_iType VrComplex
#define d_oType float
class DemodChainCF {
public:
DemodChainCF (VrSource<d_iType> *d_source, VrSink<d_oType> *d_sink, rmode_t mode, pbwidth_t width, int input_rate, freq_t centerfreq = 0) :
d_source(d_source), d_sink(d_sink), mode(mode), width(width), input_rate(input_rate), centerfreq(centerfreq), rf_gain(1.0), if_width_of_transition_band(1000), CFIRdecimate(1), RFIRdecimate(1) {}
virtual ~DemodChainCF () { delete agc; delete mixer; delete gainstage; delete audio_filter; }
virtual const char *name() { return rig_strrmode(mode); }
virtual void connect (void);
void setWidth (pbwidth_t width);
void setFreq (freq_t centerfreq);
rmode_t mode;
pbwidth_t width;
protected:
VrSource<d_iType> *d_source;
VrSink<d_oType> *d_sink;
VrSigProc *demod_in;
VrSigProc *demod_out;
HrAGC<d_oType,d_oType> *agc;
GrFreqXlatingFIRfilterCCF *mixer;
VrAmp<d_oType,d_oType> *gainstage;
GrFIRfilterFFF *audio_filter;
int input_rate;
freq_t centerfreq;
float rf_gain;
double if_width_of_transition_band;
int CFIRdecimate;
int RFIRdecimate;
};
void DemodChainCF::connect()
{
// change_filt();
vector<float> channel_coeffs =
gr_firdes::low_pass (rf_gain, // gain
input_rate, // sampling rate
width/2, // low-pass cutoff freq
if_width_of_transition_band, // width of transition band
gr_firdes::WIN_HAMMING);
rig_debug(RIG_DEBUG_VERBOSE, "Number of channel_coeffs: %d\n", channel_coeffs.size ());
vector<float> audio_coeffs =
gr_firdes::band_pass (1, // gain
input_rate, // sampling rate
300,
width,
250, // width of transition band
gr_firdes::WIN_HAMMING);
rig_debug(RIG_DEBUG_VERBOSE, "Number of audio_coeffs: %d\n", audio_coeffs.size ());
mixer = new GrFreqXlatingFIRfilterCCF (CFIRdecimate, channel_coeffs, centerfreq);
agc = new HrAGC<d_oType,d_oType>(1e-2);
gainstage = new VrAmp<float,float>(1); /* AF */
audio_filter = new GrFIRfilterFFF (RFIRdecimate, audio_coeffs);
NWO_CONNECT (d_source, mixer);
NWO_CONNECT (mixer, demod_in);
NWO_CONNECT (demod_out, agc);
NWO_CONNECT (agc, gainstage);
NWO_CONNECT (gainstage, audio_filter);
NWO_CONNECT (audio_filter, d_sink);
}
void DemodChainCF::setFreq (freq_t centerfreq)
{
rig_debug(RIG_DEBUG_TRACE,"%s: %lld\n",__FUNCTION__, centerfreq);
mixer->setCenterFreq(centerfreq);
}
void DemodChainCF::setWidth (pbwidth_t width)
{
// change_filt();
vector<float> channel_coeffs =
gr_firdes::low_pass (1.0, // gain
input_rate, // sampling rate
width/2, // low-pass cutoff freq
if_width_of_transition_band, // width of transition band
gr_firdes::WIN_HAMMING);
rig_debug(RIG_DEBUG_VERBOSE, "%s: Number of channel_coeffs: %d\n", __FUNCTION__, channel_coeffs.size ());
vector<float> audio_coeffs =
gr_firdes::band_pass (1, // gain
input_rate, // sampling rate
300,
width,
250, // width of transition band
gr_firdes::WIN_HAMMING);
rig_debug(RIG_DEBUG_VERBOSE, "Number of audio_coeffs: %d\n", audio_coeffs.size ());
mixer->setTaps(channel_coeffs);
audio_filter->setTaps(audio_coeffs);
}
#endif /* _DEMOD_H */