[debian/gnuradio] / gnuradio-core / src / lib / filter / gr_pfb_clock_sync_ccf.cc

/* -*- c++ -*- */
/*
 * Copyright 2009 Free Software Foundation, Inc.
 * 
 * This file is part of GNU Radio
 * 
 * GNU Radio is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3, or (at your option)
 * any later version.
 * 
 * GNU Radio is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <cstdio>
#include <cmath>

#include <gr_pfb_clock_sync_ccf.h>
#include <gr_fir_ccf.h>
#include <gr_fir_util.h>
#include <gr_io_signature.h>
#include <gr_math.h>

gr_pfb_clock_sync_ccf_sptr gr_make_pfb_clock_sync_ccf (float sps, float gain,
                                                       const std::vector<float> &taps,
                                                       unsigned int filter_size,
                                                       float init_phase)
{
  return gr_pfb_clock_sync_ccf_sptr (new gr_pfb_clock_sync_ccf (sps, gain, taps,
                                                                filter_size,
                                                                init_phase));
}


gr_pfb_clock_sync_ccf::gr_pfb_clock_sync_ccf (float sps, float gain,
                                              const std::vector<float> &taps,
                                              unsigned int filter_size,
                                              float init_phase)
  : gr_block ("pfb_clock_sync_ccf",
              gr_make_io_signature (1, 1, sizeof(gr_complex)),
              gr_make_io_signature2 (1, 2, sizeof(gr_complex), sizeof(float))),
    d_updated (false), d_sps(sps)
{
  d_nfilters = filter_size;

  // Store the last filter between calls to work
  // The accumulator keeps track of overflow to increment the stride correctly.
  // set it here to the fractional difference based on the initial phaes
  // assert(init_phase <= 2*M_PI);
  set_gain(gain);
  d_k = d_nfilters / 2;
  d_rate = 0;
  d_start_count = 0;
  

  d_filters = std::vector<gr_fir_ccf*>(d_nfilters);
  d_diff_filters = std::vector<gr_fir_ccf*>(d_nfilters);

  // Create an FIR filter for each channel and zero out the taps
  std::vector<float> vtaps(0, d_nfilters);
  for(unsigned int i = 0; i < d_nfilters; i++) {
    d_filters[i] = gr_fir_util::create_gr_fir_ccf(vtaps);
    d_diff_filters[i] = gr_fir_util::create_gr_fir_ccf(vtaps);
  }

  // Now, actually set the filters' taps
  std::vector<float> dtaps;
  create_diff_taps(taps, dtaps);
  set_taps(taps, d_taps, d_filters);
  set_taps(dtaps, d_dtaps, d_diff_filters);
}

gr_pfb_clock_sync_ccf::~gr_pfb_clock_sync_ccf ()
{
  for(unsigned int i = 0; i < d_nfilters; i++) {
    delete d_filters[i];
  }
}

void
gr_pfb_clock_sync_ccf::set_taps (const std::vector<float> &newtaps,
                                 std::vector< std::vector<float> > &ourtaps,
                                 std::vector<gr_fir_ccf*> &ourfilter)
{
  unsigned int i,j;

  unsigned int ntaps = newtaps.size();
  d_taps_per_filter = (unsigned int)ceil((double)ntaps/(double)d_nfilters);

  // Create d_numchan vectors to store each channel's taps
  ourtaps.resize(d_nfilters);
  
  // Make a vector of the taps plus fill it out with 0's to fill
  // each polyphase filter with exactly d_taps_per_filter
  std::vector<float> tmp_taps;
  tmp_taps = newtaps;
  while((float)(tmp_taps.size()) < d_nfilters*d_taps_per_filter) {
    tmp_taps.push_back(0.0);
  }
  
  // Partition the filter
  for(i = 0; i < d_nfilters; i++) {
    // Each channel uses all d_taps_per_filter with 0's if not enough taps to fill out
    ourtaps[i] = std::vector<float>(d_taps_per_filter, 0);
    for(j = 0; j < d_taps_per_filter; j++) {
      ourtaps[i][j] = tmp_taps[i + j*d_nfilters];  // add taps to channels in reverse order
    }
    
    // Build a filter for each channel and add it's taps to it
    ourfilter[i]->set_taps(ourtaps[i]);
  }

  // Set the history to ensure enough input items for each filter
  set_history (d_taps_per_filter + d_sps);

  d_updated = true;
}

void
gr_pfb_clock_sync_ccf::create_diff_taps(const std::vector<float> &newtaps,
                                        std::vector<float> &difftaps)
{
  float maxtap = -1e12;
  difftaps.clear();
  difftaps.push_back(0); //newtaps[0]);
  for(unsigned int i = 1; i < newtaps.size()-1; i++) {
    float tap = newtaps[i+1] - newtaps[i-1];
    if(tap > maxtap) {
     maxtap = tap;
    }
    //maxtap += tap;
    difftaps.push_back(tap);
  }
  difftaps.push_back(0);//-newtaps[newtaps.size()-1]);

  for(unsigned int i = 0; i < difftaps.size(); i++) {
    difftaps[i] /= 1;//maxtap;
  }
}

void
gr_pfb_clock_sync_ccf::print_taps()
{
  unsigned int i, j;
  for(i = 0; i < d_nfilters; i++) {
    printf("filter[%d]: [%.4e, ", i, d_taps[i][0]);
    for(j = 1; j < d_taps_per_filter-1; j++) {
      printf("%.4e,", d_taps[i][j]);
    }
    printf("%.4e]\n", d_taps[i][j]);
  }
}

void
gr_pfb_clock_sync_ccf::print_diff_taps()
{
  unsigned int i, j;
  for(i = 0; i < d_nfilters; i++) {
    printf("filter[%d]: [%.4e, ", i, d_dtaps[i][0]);
    for(j = 1; j < d_taps_per_filter-1; j++) {
      printf("%.4e,", d_dtaps[i][j]);
    }
    printf("%.4e]\n", d_dtaps[i][j]);
  }
}


std::vector<float>
gr_pfb_clock_sync_ccf::channel_taps(int channel)
{
  std::vector<float> taps;
  unsigned int i;
  for(i = 0; i < d_taps_per_filter; i++) {
    taps.push_back(d_taps[channel][i]);
  }
  return taps;
}

std::vector<float>
gr_pfb_clock_sync_ccf::diff_channel_taps(int channel)
{
  std::vector<float> taps;
  unsigned int i;
  for(i = 0; i < d_taps_per_filter; i++) {
    taps.push_back(d_dtaps[channel][i]);
  }
  return taps;
}


int
gr_pfb_clock_sync_ccf::general_work (int noutput_items,
                                     gr_vector_int &ninput_items,
                                     gr_vector_const_void_star &input_items,
                                     gr_vector_void_star &output_items)
{
  gr_complex *in = (gr_complex *) input_items[0];
  gr_complex *out = (gr_complex *) output_items[0];

  float *err;
  if(ninput_items.size() == 2)
    err = (float *) output_items[1];
  
  if (d_updated) {
    d_updated = false;
    return 0;                // history requirements may have changed.
  }

  // We need this many to process one output
  int nrequired = ninput_items[0] - d_taps_per_filter;

  int i = 0, count = d_start_count;
  float error = 0;

  // produce output as long as we can and there are enough input samples
  while((i < noutput_items) && (count < nrequired)) {
    int filtnum = (int)d_k;
    out[i] = d_filters[filtnum]->filter(&in[count]);
    error =  (out[i] * d_diff_filters[filtnum]->filter(&in[count])).real();

    if(ninput_items.size() == 2)
      err[i] = error;

    d_k = d_k + d_alpha*error + d_rate;
    d_rate = d_rate + d_beta*error;
    while(d_k >= d_nfilters) {
      d_k -= d_nfilters;
      count++;
    }
    while(d_k < 0) {
      d_k += d_nfilters;
      count--;
    }

    i++;
    count += d_sps;

    printf("error: %f  k: %f  rate: %f\n",
           error, d_k, d_rate);
  }

  // Set the start index at the next entrance to the work function
  // if we stop because we run out of input items, jump ahead in the
  // next call to work. Otherwise, we can start at zero.
  if(count > nrequired) {
    d_start_count = count - (nrequired);
    consume_each(ninput_items[0]-d_taps_per_filter);
  }
  else {
    d_start_count = 0;
    consume_each(count);
  }
  
  return i;
}