mirror of
https://github.com/f4exb/sdrangel.git
synced 2025-10-31 13:00:26 -04:00
111 lines
4.4 KiB
C
111 lines
4.4 KiB
C
|
/*---------------------------------------------------------------------------*\
|
||
|
|
|
||
|
|
FILE........: codec2_fdmdv.h
|
||
|
|
AUTHOR......: David Rowe
|
||
|
|
DATE CREATED: April 14 2012
|
||
|
|
|
||
|
|
A 1400 bit/s (nominal) Frequency Division Multiplexed Digital Voice
|
||
|
|
(FDMDV) modem. Used for digital audio over HF SSB. See
|
||
|
|
README_fdmdv.txt for more information, and fdmdv_mod.c and
|
||
|
|
fdmdv_demod.c for example usage.
|
||
|
|
|
||
|
|
The name codec2_fdmdv.h is used to make it unique when "make
|
||
|
|
installed".
|
||
|
|
|
||
|
|
References:
|
||
|
|
|
||
|
|
[1] http://n1su.com/fdmdv/FDMDV_Docs_Rel_1_4b.pdf
|
||
|
|
|
||
|
|
\*---------------------------------------------------------------------------*/
|
||
|
|
|
||
|
|
/*
|
||
|
|
Copyright (C) 2012 David Rowe
|
||
|
|
|
||
|
|
All rights reserved.
|
||
|
|
|
||
|
|
This program is free software; you can redistribute it and/or modify
|
||
|
|
it under the terms of the GNU Lesser General Public License version 2.1, as
|
||
|
|
published by the Free Software Foundation. This program 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 Lesser General Public License
|
||
|
|
along with this program; if not, see <http://www.gnu.org/licenses/>.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef __FDMDV__
|
||
|
|
#define __FDMDV__
|
||
|
|
|
||
|
|
/* set up the calling convention for DLL function import/export for
|
||
|
|
WIN32 cross compiling */
|
||
|
|
|
||
|
|
#ifdef __CODEC2_WIN32__
|
||
|
|
#ifdef __CODEC2_BUILDING_DLL__
|
||
|
|
#define CODEC2_WIN32SUPPORT __declspec(dllexport) __stdcall
|
||
|
|
#else
|
||
|
|
#define CODEC2_WIN32SUPPORT __declspec(dllimport) __stdcall
|
||
|
|
#endif
|
||
|
|
#else
|
||
|
|
#define CODEC2_WIN32SUPPORT
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#include "codec2/comp.h"
|
||
|
|
#include "modem_stats.h"
|
||
|
|
|
||
|
|
#define FDMDV_NC 14 /* default number of data carriers */
|
||
|
|
#define FDMDV_NC_MAX 20 /* maximum number of data carriers */
|
||
|
|
#define FDMDV_BITS_PER_FRAME 28 /* 20ms frames, for nominal 1400 bit/s */
|
||
|
|
#define FDMDV_NOM_SAMPLES_PER_FRAME 160 /* modulator output samples/frame and nominal demod samples/frame */
|
||
|
|
/* at 8000 Hz sample rate */
|
||
|
|
#define FDMDV_MAX_SAMPLES_PER_FRAME 200 /* max demod samples/frame, use this to allocate storage */
|
||
|
|
#define FDMDV_SCALE 1000 /* suggested scaling for 16 bit shorts */
|
||
|
|
#define FDMDV_FCENTRE 1500 /* Centre frequency, Nc/2 carriers below this, Nc/2 carriers above (Hz) */
|
||
|
|
|
||
|
|
/* 8 to 48 kHz sample rate conversion */
|
||
|
|
|
||
|
|
#define FDMDV_OS 2 /* oversampling rate */
|
||
|
|
#define FDMDV_OS_TAPS_16K 48 /* number of OS filter taps at 16kHz */
|
||
|
|
#define FDMDV_OS_TAPS_8K (FDMDV_OS_TAPS_16K/FDMDV_OS) /* number of OS filter taps at 8kHz */
|
||
|
|
|
||
|
|
namespace FreeDV
|
||
|
|
{
|
||
|
|
|
||
|
|
/* FDMDV states and stats structures */
|
||
|
|
|
||
|
|
struct FDMDV;
|
||
|
|
|
||
|
|
struct FDMDV * fdmdv_create(int Nc);
|
||
|
|
void fdmdv_destroy(struct FDMDV *fdmdv_state);
|
||
|
|
void fdmdv_use_old_qpsk_mapping(struct FDMDV *fdmdv_state);
|
||
|
|
int fdmdv_bits_per_frame(struct FDMDV *fdmdv_state);
|
||
|
|
float fdmdv_get_fsep(struct FDMDV *fdmdv_state);
|
||
|
|
void fdmdv_set_fsep(struct FDMDV *fdmdv_state, float fsep);
|
||
|
|
|
||
|
|
void fdmdv_mod(struct FDMDV *fdmdv_state, COMP tx_fdm[], int tx_bits[], int *sync_bit);
|
||
|
|
void fdmdv_demod(struct FDMDV *fdmdv_state, int rx_bits[], int *reliable_sync_bit, COMP rx_fdm[], int *nin);
|
||
|
|
|
||
|
|
void fdmdv_get_test_bits(struct FDMDV *fdmdv_state, int tx_bits[]);
|
||
|
|
int fdmdv_error_pattern_size(struct FDMDV *fdmdv_state);
|
||
|
|
void fdmdv_put_test_bits(struct FDMDV *f, int *sync, short error_pattern[], int *bit_errors, int *ntest_bits, int rx_bits[]);
|
||
|
|
|
||
|
|
void fdmdv_get_demod_stats(struct FDMDV *fdmdv_state, struct MODEM_STATS *stats);
|
||
|
|
|
||
|
|
void fdmdv_8_to_16(float out16k[], float in8k[], int n);
|
||
|
|
void fdmdv_8_to_16_short(short out16k[], short in8k[], int n);
|
||
|
|
void fdmdv_16_to_8(float out8k[], float in16k[], int n);
|
||
|
|
void fdmdv_16_to_8_short(short out8k[], short in16k[], int n);
|
||
|
|
|
||
|
|
void fdmdv_freq_shift(COMP rx_fdm_fcorr[], COMP rx_fdm[], float foff, COMP *foff_phase_rect, int nin);
|
||
|
|
|
||
|
|
/* debug/development function(s) */
|
||
|
|
|
||
|
|
void fdmdv_dump_osc_mags(struct FDMDV *f);
|
||
|
|
void fdmdv_simulate_channel(float *sig_pwr_av, COMP samples[], int nin, float target_snr);
|
||
|
|
|
||
|
|
} // FreeDV
|
||
|
|
|
||
|
|
#endif
|
||
|
|
|