radiosonde_auto_rx/demod/mod/demod_mod.h

#include <math.h>
#include <complex.h>

typedef unsigned char  ui8_t;
typedef unsigned short ui16_t;
typedef unsigned int   ui32_t;
typedef char  i8_t;
typedef short i16_t;
typedef int   i32_t;


typedef struct {
    int sr;       // sample_rate
    int LOG2N;
    int N;
    int N2;
    float *xn;
    float complex  *ew;
    float complex  *Fm;
    float complex  *X;
    float complex  *Z;
    float complex  *cx;
    float complex  *win; // float real
} dft_t;


typedef struct {
    FILE *fp;
    //
    int sr;       // sample_rate
    int bps;      // bits/sample
    int nch;      // channels
    int ch;       // select channel
    //
    int symlen;
    int symhd;
    float sps;    // samples per symbol
    float _spb;   // samples per bit
    float br;     // baud rate
    //
    ui32_t sample_in;
    ui32_t sample_out;
    ui32_t delay;
    ui32_t sc;
    int buffered;
    int L;
    int M;
    int K;
    float *match;
    float *bufs;
    float dc_ofs;
    float dc;
    float mv;
    ui32_t mv_pos;
    //
    int N_norm;
    int Nvar;
    float xsum;
    float qsum;
    float *xs;
    float *qs;

    // IQ-data
    int opt_iq;
    int N_IQBUF;
    float complex *raw_iqbuf;
    float complex *rot_iqbuf;
    float complex F1sum;
    float complex F2sum;

    //
    char *rawbits;
    char *hdr;
    int hdrlen;

    //
    float BT; // bw/time (ISI)
    float h;  // modulation index

    // DFT
    dft_t DFT;

    double df;
    int len_sq;

    ui32_t sample_posframe;
    ui32_t sample_posnoise;

    double V_noise;
    double V_signal;
    double SNRdB;

    // decimate
    int decM;
    ui32_t sr_base;
    ui32_t dectaps;
    ui32_t sample_dec;
    ui32_t lut_len;
    float complex *decXbuffer;
    float complex *decMbuf;
    float complex *ex; // exp_lut
    double xlt_fq;

    // IF: lowpass
    int opt_lp;
    int lpIQ_bw;
    int lpIQtaps; // ui32_t
    float *ws_lpIQ;
    float complex *lpIQ_buf;

} dsp_t;


typedef struct {
    int sr;       // sample_rate
    int bps;      // bits_sample  bits/sample
    int nch;      // channels
    int sel_ch;   // select wav channel
} pcm_t;



float read_wav_header(pcm_t *, FILE *);
int f32buf_sample(dsp_t *, int);
int read_slbit(dsp_t *, int*, int, int, int, float, int);

int get_fqofs_rs41(dsp_t *, ui32_t, float *, float *);
float get_bufvar(dsp_t *, int);
float get_bufmu(dsp_t *, int);

int init_buffers(dsp_t *);
int free_buffers(dsp_t *);

ui32_t get_sample(dsp_t *);

int find_header(dsp_t *, float, int, int, int);