--- /dev/null
+/* -*- c++ -*- */
+/*
+ * Copyright 2009,2010 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_fff.h>
+#include <gr_fir_fff.h>
+#include <gr_fir_util.h>
+#include <gr_io_signature.h>
+#include <gr_math.h>
+
+gr_pfb_clock_sync_fff_sptr gr_make_pfb_clock_sync_fff (double sps, float gain,
+ const std::vector<float> &taps,
+ unsigned int filter_size,
+ float init_phase,
+ float max_rate_deviation)
+{
+ return gr_pfb_clock_sync_fff_sptr (new gr_pfb_clock_sync_fff (sps, gain, taps,
+ filter_size,
+ init_phase,
+ max_rate_deviation));
+}
+
+static int ios[] = {sizeof(float), sizeof(float), sizeof(float), sizeof(float)};
+static std::vector<int> iosig(ios, ios+sizeof(ios)/sizeof(int));
+gr_pfb_clock_sync_fff::gr_pfb_clock_sync_fff (double sps, float gain,
+ const std::vector<float> &taps,
+ unsigned int filter_size,
+ float init_phase,
+ float max_rate_deviation)
+ : gr_block ("pfb_clock_sync_fff",
+ gr_make_io_signature (1, 1, sizeof(float)),
+ gr_make_io_signaturev (1, 4, iosig)),
+ d_updated (false), d_nfilters(filter_size),
+ d_max_dev(max_rate_deviation)
+{
+ d_nfilters = filter_size;
+ d_sps = floor(sps);
+
+ // 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
+ set_alpha(gain);
+ set_beta(0.25*gain*gain);
+ d_k = init_phase;
+ d_rate = (sps-floor(sps))*(double)d_nfilters;
+ d_rate_i = (int)floor(d_rate);
+ d_rate_f = d_rate - (float)d_rate_i;
+ d_filtnum = (int)floor(d_k);
+
+ d_filters = std::vector<gr_fir_fff*>(d_nfilters);
+ d_diff_filters = std::vector<gr_fir_fff*>(d_nfilters);
+
+ // Create an FIR filter for each channel and zero out the taps
+ std::vector<float> vtaps(0, d_nfilters);
+ for(int i = 0; i < d_nfilters; i++) {
+ d_filters[i] = gr_fir_util::create_gr_fir_fff(vtaps);
+ d_diff_filters[i] = gr_fir_util::create_gr_fir_fff(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_fff::~gr_pfb_clock_sync_fff ()
+{
+ for(int i = 0; i < d_nfilters; i++) {
+ delete d_filters[i];
+ delete d_diff_filters[i];
+ }
+}
+
+bool
+gr_pfb_clock_sync_fff::check_topology(int ninputs, int noutputs)
+{
+ return noutputs == 1 || noutputs == 4;
+}
+
+void
+gr_pfb_clock_sync_fff::set_taps (const std::vector<float> &newtaps,
+ std::vector< std::vector<float> > &ourtaps,
+ std::vector<gr_fir_fff*> &ourfilter)
+{
+ 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[d_nfilters-1-i] = std::vector<float>(d_taps_per_filter, 0);
+ for(j = 0; j < d_taps_per_filter; j++) {
+ ourtaps[d_nfilters - 1 - i][j] = tmp_taps[i + j*d_nfilters];
+ }
+
+ // Build a filter for each channel and add it's taps to it
+ ourfilter[i]->set_taps(ourtaps[d_nfilters-1-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_fff::create_diff_taps(const std::vector<float> &newtaps,
+ std::vector<float> &difftaps)
+{
+ float maxtap = 1e-20;
+ 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];
+ difftaps.push_back(tap);
+ if(tap > maxtap) {
+ maxtap = tap;
+ }
+ }
+ difftaps.push_back(0);//-newtaps[newtaps.size()-1]);
+
+ // Scale the differential taps; helps scale error term to better update state
+ // FIXME: should this be scaled this way or use the same gain as the taps?
+ for(unsigned int i = 0; i < difftaps.size(); i++) {
+ difftaps[i] /= maxtap;
+ }
+}
+
+void
+gr_pfb_clock_sync_fff::print_taps()
+{
+ int i, j;
+ printf("[ ");
+ for(i = 0; i < d_nfilters; i++) {
+ printf("[%.4e, ", d_taps[i][0]);
+ for(j = 1; j < d_taps_per_filter-1; j++) {
+ printf("%.4e,", d_taps[i][j]);
+ }
+ printf("%.4e],", d_taps[i][j]);
+ }
+ printf(" ]\n");
+}
+
+void
+gr_pfb_clock_sync_fff::print_diff_taps()
+{
+ int i, j;
+ printf("[ ");
+ for(i = 0; i < d_nfilters; i++) {
+ printf("[%.4e, ", d_dtaps[i][0]);
+ for(j = 1; j < d_taps_per_filter-1; j++) {
+ printf("%.4e,", d_dtaps[i][j]);
+ }
+ printf("%.4e],", d_dtaps[i][j]);
+ }
+ printf(" ]\n");
+}
+
+
+std::vector<float>
+gr_pfb_clock_sync_fff::channel_taps(int channel)
+{
+ std::vector<float> taps;
+ for(int i = 0; i < d_taps_per_filter; i++) {
+ taps.push_back(d_taps[channel][i]);
+ }
+ return taps;
+}
+
+std::vector<float>
+gr_pfb_clock_sync_fff::diff_channel_taps(int channel)
+{
+ std::vector<float> taps;
+ for(int i = 0; i < d_taps_per_filter; i++) {
+ taps.push_back(d_dtaps[channel][i]);
+ }
+ return taps;
+}
+
+
+int
+gr_pfb_clock_sync_fff::general_work (int noutput_items,
+ gr_vector_int &ninput_items,
+ gr_vector_const_void_star &input_items,
+ gr_vector_void_star &output_items)
+{
+ float *in = (float *) input_items[0];
+ float *out = (float *) output_items[0];
+
+ float *err = 0, *outrate = 0, *outk = 0;
+ if(output_items.size() == 4) {
+ err = (float *) output_items[1];
+ outrate = (float*)output_items[2];
+ outk = (float*)output_items[3];
+ }
+
+ 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 = 0;
+ float error;
+
+ // produce output as long as we can and there are enough input samples
+ while((i < noutput_items) && (count < nrequired)) {
+ d_filtnum = (int)floor(d_k);
+
+ // Keep the current filter number in [0, d_nfilters]
+ // If we've run beyond the last filter, wrap around and go to next sample
+ // If we've go below 0, wrap around and go to previous sample
+ while(d_filtnum >= d_nfilters) {
+ d_k -= d_nfilters;
+ d_filtnum -= d_nfilters;
+ count += 1;
+ }
+ while(d_filtnum < 0) {
+ d_k += d_nfilters;
+ d_filtnum += d_nfilters;
+ count -= 1;
+ }
+
+ out[i] = d_filters[d_filtnum]->filter(&in[count]);
+ float diff = d_diff_filters[d_filtnum]->filter(&in[count]);
+ error = out[i] * diff;
+
+ // Run the control loop to update the current phase (k) and tracking rate
+ d_k = d_k + d_alpha*error + d_rate_i + d_rate_f;
+ d_rate_f = d_rate_f + d_beta*error;
+
+ // Keep our rate within a good range
+ d_rate_f = gr_branchless_clip(d_rate_f, d_max_dev);
+
+ i++;
+ count += (int)floor(d_sps);
+
+ if(output_items.size() == 4) {
+ err[i] = error;
+ outrate[i] = d_rate_f;
+ outk[i] = d_k;
+ }
+ }
+ consume_each(count);
+
+ return i;
+}
projects / debian / gnuradio / blobdiff