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osmocom-analog/src/cnetz/dsp.h

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Implementation of C-Netz (German mobile telephone system)
2016-02-16 17:56:55 +00:00
void dsp_init(void);
Automatic FSK polarity selection on TX side This is done by simulating two cells with different polarities. On first message from mobile station, the cell with the correct polarity is used, the other is disabled. On RX side the polarity is not selected, since FSK decoder detects polarity for every frame.
2016-05-10 17:25:07 +00:00
int dsp_init_sender(cnetz_t *cnetz, int measure_speed, double clock_speed[2], double noise);
Implementation of C-Netz (German mobile telephone system)
2016-02-16 17:56:55 +00:00
void dsp_cleanup_sender(cnetz_t *cnetz);
void calc_clock_speed(cnetz_t *cnetz, uint64_t samples, int tx, int result);
C-Netz: Calibration/fix processing of tone levels on TX and RX side FSK and compander levels are adjusted. Eliminate offsets between subsequent speech chunks. This is done by high-pass filter. An offset is not passed to the filter. Do correct audio processing chain: time compress -> compressor -> scrambler / pre-emphasis -> TX RX -> de-scrambler / de-emphasis -> expander -> time expand
2016-05-13 06:56:26 +00:00
void unshrink_speech(cnetz_t *cnetz, int16_t *speech_buffer, int count);
Implementation of C-Netz (German mobile telephone system)
2016-02-16 17:56:55 +00:00