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#include "../libfilter/iir_filter.h"
#include "../libfilter/fir_filter.h"
typedef struct psk_mod {
int (*send_bit)(void *inst);
void *inst;
double symbol_pos; /* current position in symbol */
double symbols_per_sample; /* change of position per sample */
double phase_shift; /* carrier phase shift */
double carrier_phase; /* current carrier phase */
double carrier_phaseshift; /* shift of phase per sample */
fir_filter_t *lp[2]; /* filter for limiting spectrum */
int spl_count; /* SIT: counter for 30 samples (symbol duration) */
int sym_list[5]; /* SIT: list of 5 symbols */
int sym_count; /* SIT: current list index */
} psk_mod_t;
typedef struct psk_demod {
void (*receive_bit)(void *inst, int bit);
void *inst;
double carrier_phase; /* current carrier phase */
double carrier_phaseshift; /* shift of phase per sample */
fir_filter_t *lp[2]; /* filter for limiting spectrum */
iir_filter_t lp_error[2]; /* filter for phase correction */
iir_filter_t lp_clock; /* filter for symbol clock */
uint16_t last_phase_error; /* error phase of last sample */
int32_t phase_error; /* current phase error */
sample_t last_amplitude; /* clock amplitude of last sample */
int sample_delay; /* delay of quarter symbol length in samples */
int sample_timer; /* counter to wait for the symbol's sample point */
uint8_t last_sector; /* sector of last symbol */
} psk_demod_t;
int psk_mod_init(psk_mod_t *psk, void *inst, int (*send_bit)(void *inst), int samplerate, double symbolrate);
void psk_mod_exit(psk_mod_t *psk);
void psk_mod(psk_mod_t *psk, sample_t *sample, int length);
int psk_demod_init(psk_demod_t *psk, void *inst, void (*receive_bit)(void *inst, int bit), int samplerate, double symbolrate);
void psk_demod_exit(psk_demod_t *psk);
void psk_demod(psk_demod_t *psk, sample_t *sample, int length);
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