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SDR: Move FM modulation algorithms to a seperate file

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Andreas Eversberg
2017-02-09 19:24:09 +01:00
parent 4c0f8e7e95
commit 290b365d67
4 changed files with 240 additions and 98 deletions
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24
src/common/fm_modulation.h Normal file
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typedef struct fm_mod {
double samplerate; /* sample rate of in and out */
double offset; /* offset to calculated center frequency */
double amplitude; /* how much amplitude to add to the buff */
double phase; /* current phase of FM (used to shift and modulate ) */
double *sin_tab; /* sine/cosine table for modulation */
} fm_mod_t;
void fm_mod_init(fm_mod_t *mod, double samplerate, double offset, double amplitude);
void fm_modulate(fm_mod_t *mod, sample_t *samples, int num, float *buff);
typedef struct fm_demod {
double samplerate; /* sample rate of in and out */
double phase; /* current rotation phase (used to shift) */
double rot; /* rotation step per sample to shift rx frequency (used to shift) */
double last_phase; /* last phase of FM (used to demodulate) */
filter_t lp[2]; /* filters received IQ signal */
double *sin_tab; /* sine/cosine table rotation */
} fm_demod_t;
void fm_demod_init(fm_demod_t *demod, double samplerate, double offset, double bandwidth);
void fm_demodulate(fm_demod_t *demod, sample_t *samples, int num, float *buff);