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#include "../libwave/wave.h"
#include "../libsamplerate/samplerate.h"
#include "../libemphasis/emphasis.h"
#include "../libjitter/jitter.h"
#include "../libfm/fm.h"
#include "../libam/am.h"
#include "../libdisplay/display.h"
enum modulation {
MODULATION_NONE = 0,
MODULATION_FM,
MODULATION_AM_DSB,
MODULATION_AM_USB,
MODULATION_AM_LSB,
};
enum audio_mode {
AUDIO_MODE_NONE = 0,
AUDIO_MODE_WAVEFILE = 1,
AUDIO_MODE_AUDIODEV = 2,
AUDIO_MODE_TESTTONE = 4,
};
typedef struct radio {
/* modes */
int buffer_size; /* maximum number of samples */
enum modulation modulation; /* modulation type */
enum audio_mode tx_audio_mode; /* mode for audio source */
enum audio_mode rx_audio_mode; /* mode for audio sink */
double volume; /* volume change (gain/dampen) */
int stereo; /* use stere FM */
int rds, rds2; /* use RDS */
int emphasis; /* use pre-/de-emphasis with FM */
/* audio stage */
double tx_audio_samplerate; /* sample rate of audio source */
double rx_audio_samplerate; /* sample rate of audio sink */
int tx_audio_channels; /* number of channels of audio source */
int rx_audio_channels; /* number of channels of audio sink */
double audio_bandwidth; /* audio bandwidth */
const char *tx_wave_file; /* wave file name of source */
const char *rx_wave_file; /* wave file name of sink */
wave_play_t wave_tx_play; /* wave playback process */
wave_rec_t wave_rx_rec; /* wave record process */
void *tx_sound; /* sound card process */
void *rx_sound; /* sound card process */
jitter_t tx_dejitter[2]; /* jitter buffer when reading from sound card */
uint16_t tx_sequence[2]; /* sequence & ts for jitter buffer */
uint32_t tx_timestamp[2];
jitter_t rx_dejitter[2]; /* jitter buffer when writing to sound card */
uint16_t rx_sequence[2]; /* sequence & ts for jitter buffer */
uint32_t rx_timestamp[2];
sample_t *testtone[2]; /* test tone sample */
int testtone_length;
int testtone_pos;
dispwav_t dispwav[2]; /* display wave form */
/* signal stage */
double signal_samplerate;
double signal_bandwidth;
samplerate_t tx_resampler[2]; /* resampling from audio rate to signal rate (two channels) */
samplerate_t rx_resampler[2]; /* resampling from signal rate to audi rate (two channels) */
emphasis_t fm_emphasis[2]; /* FM pre emphasis */
double fm_deviation; /* deviation of fm signal */
fm_mod_t fm_mod; /* FM modulation */
fm_demod_t fm_demod; /* FM modulation */
double pilot_phasestep; /* phase change of pilot tone for each sample */
double tx_pilot_phase; /* current phase of tx sine */
double rx_pilot_phase; /* current phase of rx mixer */
iir_filter_t tx_dc_removal[2]; /* AM/FM DC level removal */
iir_filter_t tx_am_bw_limit; /* AM bandwidth limiter */
iir_filter_t rx_lp_pilot_I; /* low pass filter for pilot tone extraction */
iir_filter_t rx_lp_pilot_Q; /* low pass filter for pilot tone extraction */
iir_filter_t rx_lp_sum; /* filter sum signal of stereo */
iir_filter_t rx_lp_diff; /* filter differential signal of stereo */
am_mod_t am_mod; /* AM modulation */
am_demod_t am_demod; /* AM modulation */
/* buffers */
sample_t *audio_buffer;
int audio_buffer_size;
sample_t *signal_buffer;
uint8_t *signal_power_buffer;
int signal_buffer_size;
sample_t *I_buffer;
sample_t *Q_buffer;
sample_t *carrier_buffer;
} radio_t;
int radio_init(radio_t *radio, int buffer_size, int samplerate, double frequency, const char *tx_wave_file, const char *rx_wave_file, const char *tx_audiodev, const char *rx_audiodev, enum modulation modulation, double bandwidth, double deviation, double modulation_index, double time_constant, double volume, int stereo, int rds, int rds2);
void radio_exit(radio_t *radio);
int radio_start(radio_t *radio);
int radio_tx(radio_t *radio, float *baseband, int num);
int radio_rx(radio_t *radio, float *baseband, int num);
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