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direwolf/fsk_demod_state.h

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Version 1.0 - Initial commit Changes to be committed: new file: .gitattributes new file: .gitignore new file: APRStt-Implementation-Notes.pdf new file: CHANGES.txt new file: LICENSE-dire-wolf.txt new file: LICENSE-other.txt new file: Makefile.linux new file: Makefile.win new file: Quick-Start-Guide-Windows.pdf new file: Raspberry-Pi-APRS.pdf new file: User-Guide.pdf new file: aclients.c new file: aprs_tt.c new file: aprs_tt.h new file: atest.c new file: audio.c new file: audio.h new file: audio_win.c new file: ax25_pad.c new file: ax25_pad.h new file: beacon.c new file: beacon.h new file: config.c new file: config.h new file: decode_aprs.c new file: decode_aprs.h new file: dedupe.c new file: dedupe.h new file: demod.c new file: demod.h new file: demod_9600.c new file: demod_9600.h new file: demod_afsk.c new file: demod_afsk.h new file: digipeater.c new file: digipeater.h new file: direwolf.c new file: direwolf.conf new file: direwolf.desktop new file: direwolf.h new file: dsp.c new file: dsp.h new file: dtmf.c new file: dtmf.h new file: dw-icon.ico new file: dw-icon.png new file: dw-icon.rc new file: dw-start.sh new file: dwgps.c new file: dwgps.h new file: encode_aprs.c new file: encode_aprs.h new file: fcs_calc.c new file: fcs_calc.h new file: fsk_demod_agc.h new file: fsk_demod_state.h new file: fsk_filters.h new file: fsk_gen_filter.h new file: gen_packets.c new file: gen_tone.c new file: gen_tone.h new file: hdlc_rec.c new file: hdlc_rec.h new file: hdlc_rec2.c new file: hdlc_rec2.h new file: hdlc_send.c new file: hdlc_send.h new file: igate.c new file: igate.h new file: kiss.c new file: kiss.h new file: kiss_frame.c new file: kiss_frame.h new file: kissnet.c new file: kissnet.h new file: latlong.c new file: latlong.h new file: ll2utm.c new file: misc/README-dire-wolf.txt new file: misc/strcasestr.c new file: misc/strsep.c new file: misc/strtok_r.c new file: morse.c new file: multi_modem.c new file: multi_modem.h new file: ptt.c new file: ptt.h new file: pttest.c new file: rdq.c new file: rdq.h new file: redecode.c new file: redecode.h new file: regex/COPYING new file: regex/INSTALL new file: regex/LICENSES new file: regex/NEWS new file: regex/README new file: regex/README-dire-wolf.txt new file: regex/re_comp.h new file: regex/regcomp.c new file: regex/regex.c new file: regex/regex.h new file: regex/regex_internal.c new file: regex/regex_internal.h new file: regex/regexec.c new file: rrbb.c new file: rrbb.h new file: server.c new file: server.h new file: symbols-new.txt new file: symbols.c new file: symbols.h new file: symbolsX.txt new file: textcolor.c new file: textcolor.h new file: tocalls.txt new file: tq.c new file: tq.h new file: tt_text.c new file: tt_text.h new file: tt_user.c new file: tt_user.h new file: tune.h new file: udp_test.c new file: utm/LatLong-UTMconversion.c new file: utm/LatLong-UTMconversion.h new file: utm/README.txt new file: utm/SwissGrid.cpp new file: utm/UTMConversions.cpp new file: utm/constants.h new file: utm2ll.c new file: version.h new file: xmit.c new file: xmit.h
2015-07-27 00:35:07 +00:00
/* fsk_demod_state.h */
#ifndef FSK_DEMOD_STATE_H
/*
* Demodulator state.
* Different copy is required for each channel & subchannel being processed concurrently.
*/
typedef enum bp_window_e { BP_WINDOW_TRUNCATED,
BP_WINDOW_COSINE,
BP_WINDOW_HAMMING,
BP_WINDOW_BLACKMAN,
BP_WINDOW_FLATTOP } bp_window_t;
struct demodulator_state_s
{
/*
* These are set once during initialization.
*/
#define TICKS_PER_PLL_CYCLE ( 256.0 * 256.0 * 256.0 * 256.0 )
int pll_step_per_sample; // PLL is advanced by this much each audio sample.
// Data is sampled when it overflows.
int ms_filter_size; /* Size of mark & space filters, in audio samples. */
/* Started off as a guess of one bit length */
/* but somewhat longer turned out to be better. */
/* Currently using same size for any prefilter. */
#define MAX_FILTER_SIZE 320 /* 304 is needed for profile C, 300 baud & 44100. */
/*
* FIR filter length relative to one bit time.
* Use same for both bandpass and lowpass.
*/
float filter_len_bits;
/*
* Window type for the mark/space filters.
*/
bp_window_t bp_window;
/*
* Alternate Low pass filters.
* First is arbitrary number for quick IIR.
* Second is frequency as ratio to baud rate for FIR.
*/
int lpf_use_fir; /* 0 for IIR, 1 for FIR. */
float lpf_iir;
float lpf_baud;
/*
* Automatic gain control. Fast attack and slow decay factors.
*/
float agc_fast_attack;
float agc_slow_decay;
/*
* Hysteresis before final demodulator 0 / 1 decision.
*/
float hysteresis;
/*
* Phase Locked Loop (PLL) inertia.
* Larger number means less influence by signal transitions.
*/
float pll_locked_inertia;
float pll_searching_inertia;
/*
* Optional band pass pre-filter before mark/space detector.
*/
int use_prefilter; /* True to enable it. */
float prefilter_baud; /* Cutoff frequencies, as fraction of */
/* baud rate, beyond tones used. */
/* Example, if we used 1600/1800 tones at */
/* 300 baud, and this was 0.5, the cutoff */
/* frequencies would be: */
/* lower = min(1600,1800) - 0.5 * 300 = 1450 */
/* upper = max(1600,1800) + 0.5 * 300 = 1950 */
float pre_filter[MAX_FILTER_SIZE] __attribute__((aligned(16)));
/*
* Kernel for the mark and space detection filters.
*/
float m_sin_table[MAX_FILTER_SIZE] __attribute__((aligned(16)));
float m_cos_table[MAX_FILTER_SIZE] __attribute__((aligned(16)));
float s_sin_table[MAX_FILTER_SIZE] __attribute__((aligned(16)));
float s_cos_table[MAX_FILTER_SIZE] __attribute__((aligned(16)));
/*
* The rest are continuously updated.
*/
signed int data_clock_pll; // PLL for data clock recovery.
// It is incremented by pll_step_per_sample
// for each audio sample.
signed int prev_d_c_pll; // Previous value of above, before
// incrementing, to detect overflows.
/*
* Most recent raw audio samples, before/after prefiltering.
*/
float raw_cb[MAX_FILTER_SIZE] __attribute__((aligned(16)));
/*
* Input to the mark/space detector.
* Could be prefiltered or raw audio.
*/
float ms_in_cb[MAX_FILTER_SIZE] __attribute__((aligned(16)));
/*
* Outputs from the mark and space amplitude detection,
* used as inputs to the FIR lowpass filters.
* Kernel for the lowpass filters.
*/
int lp_filter_size;
float m_amp_cb[MAX_FILTER_SIZE] __attribute__((aligned(16)));
float s_amp_cb[MAX_FILTER_SIZE] __attribute__((aligned(16)));
float lp_filter[MAX_FILTER_SIZE] __attribute__((aligned(16)));
float m_peak, s_peak;
float m_valley, s_valley;
float m_amp_prev, s_amp_prev;
int prev_demod_data; // Previous data bit detected.
// Used to look for transitions.
/* These are used only for "9600" baud data. */
int lfsr; // Descrambler shift register.
/*
* Finally, try to come up with some sort of measure of the audio input level.
* Let's try gathering both the peak and average of the
* absolute value of the input signal over some period such as 100 mS.
*
*/
int lev_period; // How many samples go into one measure.
int lev_count; // Number accumulated so far.
float lev_peak_acc; // Highest peak so far.
float lev_sum_acc; // Accumulated sum so far.
/*
* These will be updated every 'lev_period' samples:
*/
float lev_last_peak;
float lev_last_ave;
float lev_prev_peak;
float lev_prev_ave;
};
#define FSK_DEMOD_STATE_H 1
#endif