Ejemplo n.º 1
0
/* the gateway function */
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{

  srslte_cell_t cell; 
  srslte_pss_synch_t pss; 
  cf_t *input_symbols;
  int frame_len; 
  
  if (nrhs < NOF_INPUTS) {
    help();
    return;
  }
    
  srslte_use_standard_symbol_size(true);  
    
  if (mexutils_read_cell(ENBCFG, &cell)) {
    help();
    return;
  }
  
  /* Allocate input buffers */
  frame_len = mexutils_read_cf(INPUT, &input_symbols);
  if (frame_len < 0) {
    mexErrMsgTxt("Error reading input symbols\n");
    return;
  }
  
  if (nrhs == NOF_INPUTS+1) {
    frame_len = (int) mxGetScalar(prhs[NOF_INPUTS]);
  }
  
  if (srslte_pss_synch_init_fft(&pss, frame_len, srslte_symbol_sz(cell.nof_prb))) {
    fprintf(stderr, "Error initiating PSS\n");
    exit(-1);
  }
  if (srslte_pss_synch_set_N_id_2(&pss, cell.id%3)) {
    fprintf(stderr, "Error setting N_id_2=%d\n",cell.id%3);
    exit(-1);
  }
  srslte_pss_synch_set_ema_alpha(&pss, 1.0);     
      
  int peak_idx = srslte_pss_synch_find_pss(&pss, input_symbols, NULL);

  if (nlhs >= 1) { 
    plhs[0] = mxCreateDoubleScalar(peak_idx);
  }
  if (nlhs >= 2) {
    mexutils_write_cf(pss.conv_output, &plhs[1], frame_len, 1);  
  }
    
  srslte_pss_synch_free(&pss);
  free(input_symbols);

  return;
}
Ejemplo n.º 2
0
/* the gateway function */
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
  int i; 
  srslte_cell_t cell; 
  srslte_ofdm_t ofdm_rx; 
  srslte_pdsch_t pdsch;
  srslte_chest_dl_t chest; 
  cf_t *input_fft;
  srslte_pdsch_cfg_t cfg;
  srslte_softbuffer_rx_t softbuffer; 
  uint32_t rnti32;
  uint32_t cfi; 

  if (nrhs < NOF_INPUTS) {
    help();
    return;
  }

  srslte_verbose = SRSLTE_VERBOSE_DEBUG;
  bzero(&cfg, sizeof(srslte_pdsch_cfg_t));

  if (mexutils_read_cell(ENBCFG, &cell)) {
    help();
    return;
  }
  
  if (mexutils_read_uint32_struct(PDSCHCFG, "RNTI", &rnti32)) {
    mexErrMsgTxt("Field RNTI not found in pdsch config\n");
    return;
  }
  
  if (mexutils_read_uint32_struct(ENBCFG, "CFI", &cfi)) {
    help();
    return;
  }
  if (mexutils_read_uint32_struct(ENBCFG, "NSubframe", &cfg.sf_idx)) {
    help();
    return;
  }

  if (srslte_ofdm_rx_init(&ofdm_rx, cell.cp, cell.nof_prb)) {
    fprintf(stderr, "Error initializing FFT\n");
    return;
  }

  if (srslte_pdsch_init(&pdsch, cell)) {
    mexErrMsgTxt("Error initiating PDSCH\n");
    return;
  }
  srslte_pdsch_set_rnti(&pdsch, (uint16_t) (rnti32 & 0xffff));

  if (srslte_softbuffer_rx_init(&softbuffer, cell.nof_prb)) {
    mexErrMsgTxt("Error initiating soft buffer\n");
    return;
  }
  
  if (srslte_chest_dl_init(&chest, cell)) {
    mexErrMsgTxt("Error initializing equalizer\n");
    return;
  }

  srslte_ra_dl_grant_t grant; 
  grant.mcs.tbs = mxGetScalar(TBS);
  if (grant.mcs.tbs == 0) {
    mexErrMsgTxt("Error trblklen is zero\n");
    return;
  }
  if (srslte_cbsegm(&cfg.cb_segm, grant.mcs.tbs)) {
    mexErrMsgTxt("Error computing CB segmentation\n");
    return; 
  }

  if (mexutils_read_uint32_struct(PDSCHCFG, "RV", &cfg.rv)) {
    mexErrMsgTxt("Field RV not found in pdsch config\n");
    return;
  }

  uint32_t max_iterations = 5;
  mexutils_read_uint32_struct(PDSCHCFG, "NTurboDecIts", &max_iterations);
  
  char *mod_str = mexutils_get_char_struct(PDSCHCFG, "Modulation");
  
  if (!strcmp(mod_str, "QPSK")) {
    grant.mcs.mod = SRSLTE_MOD_QPSK;
  } else if (!strcmp(mod_str, "16QAM")) {
    grant.mcs.mod = SRSLTE_MOD_16QAM;
  } else if (!strcmp(mod_str, "64QAM")) {
    grant.mcs.mod = SRSLTE_MOD_64QAM;
  } else {
   mexErrMsgTxt("Unknown modulation\n");
   return;
  }

  mxFree(mod_str);
  
  mxArray *p; 
  p = mxGetField(PDSCHCFG, 0, "PRBSet");
  if (!p) {
    mexErrMsgTxt("Error field PRBSet not found\n");
    return;
  } 
  
  float *prbset_f;
  uint64_t *prbset;
  if (mxGetClassID(p) == mxDOUBLE_CLASS) {
    grant.nof_prb = mexutils_read_f(p, &prbset_f);
    prbset = malloc(sizeof(uint64_t)*grant.nof_prb);
    for (i=0;i<grant.nof_prb;i++) {
      prbset[i] = (uint64_t) prbset_f[i];
    }
  } else {
    grant.nof_prb = mexutils_read_uint64(p, &prbset);
  }
  
  for (i=0;i<cell.nof_prb;i++) {
    grant.prb_idx[0][i] = false; 
    for (int j=0;j<grant.nof_prb && !grant.prb_idx[0][i];j++) {
      if ((int) prbset[j] == i) {
        grant.prb_idx[0][i] = true;
      }
    }
    grant.prb_idx[1][i] = grant.prb_idx[0][i];
  }
  
  free(prbset);
  
  /* Configure rest of pdsch_cfg parameters */
  grant.Qm = srslte_mod_bits_x_symbol(grant.mcs.mod);
  if (srslte_pdsch_cfg(&cfg, cell, &grant, cfi, cfg.sf_idx, cfg.rv)) {
    fprintf(stderr, "Error configuring PDSCH\n");
    exit(-1);
  }
      
  /** Allocate input buffers */
  int nof_retx=1; 
  if (mexutils_isCell(INPUT)) {
    nof_retx = mexutils_getLength(INPUT);
  } 
  
  cf_t *ce[SRSLTE_MAX_PORTS];
  for (i=0;i<cell.nof_ports;i++) {
    ce[i] = srslte_vec_malloc(SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
  }

  uint8_t *data_bytes = srslte_vec_malloc(sizeof(uint8_t) * grant.mcs.tbs/8);
  if (!data_bytes) {
    return;
  }
  srslte_sch_set_max_noi(&pdsch.dl_sch, max_iterations);

  input_fft = NULL; 
  int r=-1;
  for (int rvIdx=0;rvIdx<nof_retx && r != 0;rvIdx++) {
    
    mxArray *tmp = (mxArray*) INPUT; 
    if (mexutils_isCell(INPUT)) {
      tmp = mexutils_getCellArray(INPUT, rvIdx);
      if (nof_retx > 1) {
        cfg.rv = rv_seq[rvIdx%4];
      }
    } 
    
    // Read input signal 
    cf_t *input_signal = NULL; 
    int insignal_len = mexutils_read_cf(tmp, &input_signal);
    if (insignal_len < 0) {
      mexErrMsgTxt("Error reading input signal\n");
      return; 
    }
    if (insignal_len == SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp)) {
      input_fft = input_signal; 
    } else {
      input_fft = srslte_vec_malloc(SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));  
      srslte_ofdm_rx_sf(&ofdm_rx, input_signal, input_fft);
      free(input_signal);
    }
    
    if (nrhs > NOF_INPUTS) {
      cf_t *cearray = NULL; 
      mexutils_read_cf(prhs[NOF_INPUTS], &cearray);
      cf_t *cearray_ptr = cearray; 
      for (i=0;i<cell.nof_ports;i++) {
        for (int j=0;j<SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp);j++) {
          ce[i][j] = *cearray_ptr;
          cearray_ptr++;
        }
      }    
      if (cearray)
        free(cearray);
    } else {
      srslte_chest_dl_estimate(&chest, input_fft, ce, cfg.sf_idx);    
    }
    
    float noise_power;
    if (nrhs > NOF_INPUTS + 1) {
      noise_power = mxGetScalar(prhs[NOF_INPUTS+1]);
    } else if (nrhs > NOF_INPUTS) {
      noise_power = 0; 
    } else {
      noise_power = srslte_chest_dl_get_noise_estimate(&chest);
    }

    r = srslte_pdsch_decode(&pdsch, &cfg, &softbuffer, input_fft, ce, noise_power, data_bytes);
  }
  
  uint8_t *data = malloc(grant.mcs.tbs);
  srslte_bit_unpack_vector(data_bytes, data, grant.mcs.tbs);
  
  if (nlhs >= 1) { 
    plhs[0] = mxCreateLogicalScalar(r == 0);
  }
  if (nlhs >= 2) {
    mexutils_write_uint8(data, &plhs[1], grant.mcs.tbs, 1);  
  }
  if (nlhs >= 3) {
    mexutils_write_cf(pdsch.symbols[0], &plhs[2], cfg.nbits.nof_re, 1);  
  }
  if (nlhs >= 4) {
    mexutils_write_cf(pdsch.d, &plhs[3], cfg.nbits.nof_re, 1);  
  }
  if (nlhs >= 5) {
    mexutils_write_s(pdsch.e, &plhs[4], cfg.nbits.nof_bits, 1);  
  }
  
  srslte_softbuffer_rx_free(&softbuffer);
  srslte_chest_dl_free(&chest);
  srslte_pdsch_free(&pdsch);
  srslte_ofdm_rx_free(&ofdm_rx);
  
  for (i=0;i<cell.nof_ports;i++) {
    free(ce[i]);
  }
  free(data_bytes);
  free(data);
  if (input_fft) {
    free(input_fft); 
  }
  
  return;
}
Ejemplo n.º 3
0
/* the gateway function */
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
  int i; 
  srslte_cell_t cell; 
  srslte_pdsch_t pdsch;
  srslte_chest_dl_t chest; 
  srslte_ofdm_t fft; 
  cf_t *input_fft, *input_signal;
  int nof_re; 
  srslte_pdsch_cfg_t cfg;
  srslte_softbuffer_rx_t softbuffer; 
  uint32_t rnti32;
  uint32_t cfi; 

  if (nrhs < NOF_INPUTS) {
    help();
    return;
  }

  bzero(&cfg, sizeof(srslte_pdsch_cfg_t));

  if (mexutils_read_cell(ENBCFG, &cell)) {
    help();
    return;
  }
  
  if (mexutils_read_uint32_struct(PDSCHCFG, "RNTI", &rnti32)) {
    mexErrMsgTxt("Field RNTI not found in pdsch config\n");
    return;
  }
  
  if (mexutils_read_uint32_struct(ENBCFG, "CFI", &cfi)) {
    help();
    return;
  }
  if (mexutils_read_uint32_struct(ENBCFG, "NSubframe", &cfg.sf_idx)) {
    help();
    return;
  }

  if (srslte_pdsch_init(&pdsch, cell)) {
    mexErrMsgTxt("Error initiating PDSCH\n");
    return;
  }
  srslte_pdsch_set_rnti(&pdsch, (uint16_t) (rnti32 & 0xffff));

  if (srslte_softbuffer_rx_init(&softbuffer, cell)) {
    mexErrMsgTxt("Error initiating soft buffer\n");
    return;
  }
  
  if (srslte_chest_dl_init(&chest, cell)) {
    mexErrMsgTxt("Error initializing equalizer\n");
    return;
  }

  if (srslte_ofdm_rx_init(&fft, cell.cp, cell.nof_prb)) {
    mexErrMsgTxt("Error initializing FFT\n");
    return;
  }
  
  nof_re = 2 * SRSLTE_CP_NORM_NSYMB * cell.nof_prb * SRSLTE_NRE;

  cfg.grant.mcs.tbs = mxGetScalar(TBS);
  if (cfg.grant.mcs.tbs == 0) {
    mexErrMsgTxt("Error trblklen is zero\n");
    return;
  }
  if (srslte_cbsegm(&cfg.cb_segm, cfg.grant.mcs.tbs)) {
    mexErrMsgTxt("Error computing CB segmentation\n");
    return; 
  }

  if (mexutils_read_uint32_struct(PDSCHCFG, "RV", &cfg.rv)) {
    mexErrMsgTxt("Field RV not found in pdsch config\n");
    return;
  }
  
  char *mod_str = mexutils_get_char_struct(PDSCHCFG, "Modulation");
  
  if (!strcmp(mod_str, "QPSK")) {
    cfg.grant.mcs.mod = SRSLTE_MOD_QPSK;
  } else if (!strcmp(mod_str, "16QAM")) {
    cfg.grant.mcs.mod = SRSLTE_MOD_16QAM;
  } else if (!strcmp(mod_str, "64QAM")) {
    cfg.grant.mcs.mod = SRSLTE_MOD_64QAM;
  } else {
   mexErrMsgTxt("Unknown modulation\n");
   return;
  }

  mxFree(mod_str);
  
  float *prbset; 
  mxArray *p; 
  p = mxGetField(PDSCHCFG, 0, "PRBSet");
  if (!p) {
    mexErrMsgTxt("Error field PRBSet not found\n");
    return;
  } 
  
  // Only localized PRB supported 
  cfg.grant.nof_prb = mexutils_read_f(p, &prbset);

  for (i=0;i<cell.nof_prb;i++) {
    cfg.grant.prb_idx[0][i] = false; 
    for (int j=0;j<cfg.grant.nof_prb && !cfg.grant.prb_idx[0][i];j++) {
      if ((int) prbset[j] == i) {
        cfg.grant.prb_idx[0][i] = true;
      }
    }
  }
  memcpy(&cfg.grant.prb_idx[1], &cfg.grant.prb_idx[0], SRSLTE_MAX_PRB*sizeof(bool));

  free(prbset);
  
  srslte_dl_dci_to_grant_nof_re(&cfg.grant, cell, cfg.sf_idx, cell.nof_prb<10?(cfi+1):cfi);
  
  // Fill rest of grant structure 
  cfg.grant.lstart = cell.nof_prb<10?(cfi+1):cfi;
  cfg.grant.nof_symb = 2*SRSLTE_CP_NSYMB(cell.cp)-cfg.grant.lstart;
  cfg.grant.Qm = srslte_mod_bits_x_symbol(cfg.grant.mcs.mod);
  cfg.grant.nof_bits = cfg.grant.nof_re * cfg.grant.Qm;     
    
  /** Allocate input buffers */
  if (mexutils_read_cf(INPUT, &input_signal) < 0) {
    mexErrMsgTxt("Error reading input signal\n");
    return; 
  }
  input_fft = srslte_vec_malloc(SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
  
  cf_t *ce[SRSLTE_MAX_PORTS];
  for (i=0;i<cell.nof_ports;i++) {
    ce[i] = srslte_vec_malloc(SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
  }
  
  srslte_ofdm_rx_sf(&fft, input_signal, input_fft);

  if (nrhs > NOF_INPUTS) {
    cf_t *cearray = NULL; 
    nof_re = mexutils_read_cf(prhs[NOF_INPUTS], &cearray);
    cf_t *cearray_ptr = cearray; 
    for (i=0;i<cell.nof_ports;i++) {
      for (int j=0;j<nof_re/cell.nof_ports;j++) {
        ce[i][j] = *cearray;
        cearray++;
      }
    }    
    if (cearray_ptr)
      free(cearray_ptr);
  } else {
    srslte_chest_dl_estimate(&chest, input_fft, ce, cfg.sf_idx);    
  }
  float noise_power;
  if (nrhs > NOF_INPUTS + 1) {
    noise_power = mxGetScalar(prhs[NOF_INPUTS+1]);
  } else {
    noise_power = srslte_chest_dl_get_noise_estimate(&chest);
  }
  
  uint8_t *data = malloc(sizeof(uint8_t) * cfg.grant.mcs.tbs);
  if (!data) {
    return;
  }

  int r = srslte_pdsch_decode(&pdsch, &cfg, &softbuffer, input_fft, ce, noise_power, data);

  
  if (nlhs >= 1) { 
    plhs[0] = mxCreateLogicalScalar(r == 0);
  }
  if (nlhs >= 2) {
    mexutils_write_uint8(data, &plhs[1], cfg.grant.mcs.tbs, 1);  
  }
  if (nlhs >= 3) {
    mexutils_write_cf(pdsch.symbols[0], &plhs[2], cfg.grant.nof_re, 1);  
  }
  if (nlhs >= 4) {
    mexutils_write_cf(pdsch.d, &plhs[3], cfg.grant.nof_re, 1);  
  }
  if (nlhs >= 5) {
    mexutils_write_f(pdsch.e, &plhs[4], cfg.grant.nof_bits, 1);  
  }
  
  srslte_chest_dl_free(&chest);
  srslte_ofdm_rx_free(&fft);
  srslte_pdsch_free(&pdsch);
  
  for (i=0;i<cell.nof_ports;i++) {
    free(ce[i]);
  }
  free(data);
  free(input_signal);
  free(input_fft);
  
  return;
}
Ejemplo n.º 4
0
/* the gateway function */
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
  int i; 
  lte_cell_t cell; 
  pcfich_t pcfich;
  chest_dl_t chest; 
  lte_fft_t fft; 
  regs_t regs;
  uint32_t sf_idx; 
  cf_t *input_fft, *input_signal;
  
  if (nrhs != NOF_INPUTS) {
    help();
    return;
  }
    
  if (mexutils_read_cell(ENBCFG, &cell)) {
    help();
    return;
  }
  
  if (mexutils_read_uint32_struct(ENBCFG, "NSubframe", &sf_idx)) {
    help();
    return;
  }

  if (chest_dl_init(&chest, cell)) {
    mexErrMsgTxt("Error initializing equalizer\n");
    return;
  }

  if (lte_fft_init(&fft, cell.cp, cell.nof_prb)) {
    mexErrMsgTxt("Error initializing FFT\n");
    return;
  }
  
  if (regs_init(&regs, cell)) {
    mexErrMsgTxt("Error initiating regs\n");
    return;
  }
  
  if (pcfich_init(&pcfich, &regs, cell)) {
    mexErrMsgTxt("Error creating PBCH object\n");
    return;
  }
      
  /** Allocate input buffers */
  if (mexutils_read_cf(INPUT, &input_signal) < 0) {
    mexErrMsgTxt("Error reading input signal\n");
    return; 
  }
  input_fft = vec_malloc(SF_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
  
  // Set Channel estimates to 1.0 (ignore fading) 
  cf_t *ce[MAX_PORTS];
  for (i=0;i<cell.nof_ports;i++) {
    ce[i] = vec_malloc(SF_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
  }
  
  lte_fft_run_sf(&fft, input_signal, input_fft);

  if (nrhs > NOF_INPUTS) {
    cf_t *cearray; 
    mexutils_read_cf(prhs[NOF_INPUTS], &cearray);
    for (i=0;i<cell.nof_ports;i++) {
      for (int j=0;j<SF_LEN_RE(cell.nof_prb, cell.cp);j++) {
        ce[i][j] = *cearray;
        cearray++;
      }
    }
  } else {
    chest_dl_estimate(&chest, input_fft, ce, sf_idx);    
  }
  float noise_power;
  if (nrhs > NOF_INPUTS + 1) {
    noise_power = mxGetScalar(prhs[NOF_INPUTS+1]);
  } else {
    noise_power = chest_dl_get_noise_estimate(&chest);
  }
    
    
  uint32_t cfi;
  float corr_res; 
  int n = pcfich_decode(&pcfich, input_fft, ce, noise_power,  sf_idx, &cfi, &corr_res);

  if (nlhs >= 1) { 
    if (n < 0) {      
      plhs[0] = mxCreateDoubleScalar(-1);
    } else {
      plhs[0] = mxCreateDoubleScalar(cfi);      
    }
  }
  if (nlhs >= 2) {
    mexutils_write_cf(pcfich.pcfich_d, &plhs[1], 16, 1);  
  }
  if (nlhs >= 3) {
    mexutils_write_cf(pcfich.pcfich_symbols[0], &plhs[2], 16, 1);  
  }
  
  chest_dl_free(&chest);
  lte_fft_free(&fft);
  pcfich_free(&pcfich);
  regs_free(&regs);
  
  for (i=0;i<cell.nof_ports;i++) {
    free(ce[i]);
  }
  free(input_signal);
  free(input_fft);
  
  return;
}
Ejemplo n.º 5
0
/* the gateway function */
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
  cf_t *input = NULL;
  cf_t *hest = NULL; 
  cf_t *output = NULL; 
  uint32_t nof_symbols = 0; 
  
  if (nrhs < NOF_INPUTS) {
    help();
    return;
  }
  
  // Read input symbols
  nof_symbols = mexutils_read_cf(INPUT, &input);
  if (nof_symbols < 0) {
    mexErrMsgTxt("Error reading input\n");
    return; 
  }
  // Read channel estimates
  uint32_t nof_symbols2 = mexutils_read_cf(HEST, &hest);
  if (nof_symbols < 0) {
    mexErrMsgTxt("Error reading hest\n");
    return; 
  }
  if ((nof_symbols2 % nof_symbols) != 0) {
    mexErrMsgTxt("Hest size must be multiple of input size\n");
    return; 
  }
  // Calculate number of ports
  uint32_t nof_ports = nof_symbols2/nof_symbols; 
  
  cf_t *x[8]; 
  cf_t *h[4];
  
  /* Allocate memory */
  output = srslte_vec_malloc(sizeof(cf_t)*nof_symbols);
  int i;
  for (i = 0; i < nof_ports; i++) {
    x[i] = srslte_vec_malloc(sizeof(cf_t)*nof_symbols);
    h[i] = &hest[i*nof_symbols];
  }
  for (;i<8;i++) {
    x[i] = NULL; 
  }
  for (i=nof_ports;i<4;i++) {
    h[i] = NULL; 
  }
  
  srslte_predecoding_diversity(input, h, x, nof_ports, nof_symbols); 
  srslte_layerdemap_diversity(x, output, nof_ports, nof_symbols / nof_ports);


  if (nlhs >= 1) { 
    mexutils_write_cf(output, &plhs[0], nof_symbols, 1);  
  }
  
  if (input) {
    free(input);
  }
  if (output) {
    free(output);
  }
  for (i=0;i<8;i++) {
    if (x[i]) {
      free(x[i]);      
    }
  }

  return;
}
Ejemplo n.º 6
0
/* the gateway function */
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
  int i; 
  srslte_cell_t cell; 
  srslte_phich_t phich;
  srslte_chest_dl_t chest; 
  srslte_ofdm_t ofdm_rx; 
  srslte_regs_t regs;
  uint32_t sf_idx; 
  cf_t *input_fft, *input_signal;
  
  if (nrhs < NOF_INPUTS) {
    help();
    return;
  }
    
  if (mexutils_read_cell(ENBCFG, &cell)) {
    help();
    return;
  }
  
  if (mexutils_read_uint32_struct(ENBCFG, "NSubframe", &sf_idx)) {
    help();
    return;
  }

  if (srslte_chest_dl_init(&chest, cell)) {
    mexErrMsgTxt("Error initializing equalizer\n");
    return;
  }

  if (srslte_ofdm_rx_init(&ofdm_rx, cell.cp, cell.nof_prb)) {
    mexErrMsgTxt("Error initializing FFT\n");
    return;
  }
  
  if (srslte_regs_init(&regs, cell)) {
    mexErrMsgTxt("Error initiating regs\n");
    return;
  }
  
  if (srslte_phich_init(&phich, &regs, cell)) {
    mexErrMsgTxt("Error creating PHICH object\n");
    return;
  }
      
// Read input signal 
  input_signal = NULL; 
  int insignal_len = mexutils_read_cf(INPUT, &input_signal);
  if (insignal_len < 0) {
    mexErrMsgTxt("Error reading input signal\n");
    return; 
  }
  if (insignal_len == SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp)) {
    input_fft = input_signal; 
  } else {
    input_fft = srslte_vec_malloc(SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));  
    srslte_ofdm_rx_sf(&ofdm_rx, input_signal, input_fft);
    free(input_signal);
  }  
  
  cf_t *ce[SRSLTE_MAX_PORTS];
  for (i=0;i<cell.nof_ports;i++) {
    ce[i] = srslte_vec_malloc(SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp) * sizeof(cf_t));
  }
  
  if (nrhs > NOF_INPUTS) {
    cf_t *cearray = NULL; 
    mexutils_read_cf(prhs[NOF_INPUTS], &cearray);
    cf_t *cearray_ptr = cearray; 
    for (i=0;i<cell.nof_ports;i++) {
      for (int j=0;j<SRSLTE_SF_LEN_RE(cell.nof_prb, cell.cp);j++) {
        ce[i][j] = *cearray_ptr;
        cearray_ptr++;
      }
    }
    if (cearray) {
      free(cearray);
    }
  } else {
    srslte_chest_dl_estimate(&chest, input_fft, ce, sf_idx);    
  }
  float noise_power;
  if (nrhs > NOF_INPUTS + 1) {
    noise_power = mxGetScalar(prhs[NOF_INPUTS+1]);
  } else if (nrhs > NOF_INPUTS) {
    noise_power = 0; 
  } else {
    noise_power = srslte_chest_dl_get_noise_estimate(&chest);
  } 
  
  // Read hires values 
  float *hires = NULL; 
  int nhires = mexutils_read_f(HIRES, &hires); 
  if (nhires != 2) {
    mexErrMsgTxt("Expecting 2 values for hires parameter\n");
    return; 
  }
  uint32_t ngroup = (uint32_t) hires[0]; 
  uint32_t nseq   = (uint32_t) hires[1]; 
  uint8_t ack;
  float corr_res; 
  int n = srslte_phich_decode(&phich, input_fft, ce, noise_power, ngroup, nseq, sf_idx, &ack, &corr_res);

  if (nlhs >= 1) { 
    if (n < 0) {      
      plhs[0] = mxCreateDoubleScalar(-1);
    } else {
      plhs[0] = mxCreateDoubleScalar(ack);      
    }
  }
  if (nlhs >= 2) {
    mexutils_write_cf(phich.z, &plhs[1], 1, SRSLTE_PHICH_NBITS);  
  }
  
  srslte_chest_dl_free(&chest);
  srslte_ofdm_rx_free(&ofdm_rx);
  srslte_phich_free(&phich);
  srslte_regs_free(&regs);
  
  for (i=0;i<cell.nof_ports;i++) {
    free(ce[i]);
  }
  free(input_fft);
  
  return;
}