3 * Copyright 2009 Free Software Foundation, Inc.
5 * This file is part of GNU Radio
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8 * it under the terms of the GNU General Public License as published by
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14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
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19 * the Free Software Foundation, Inc., 51 Franklin Street,
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30 #include <gr_pfb_clock_sync_ccf.h>
31 #include <gr_fir_ccf.h>
32 #include <gr_fir_util.h>
33 #include <gr_io_signature.h>
36 gr_pfb_clock_sync_ccf_sptr gr_make_pfb_clock_sync_ccf (double sps, float gain,
37 const std::vector<float> &taps,
38 unsigned int filter_size,
40 float max_rate_deviation)
42 return gr_pfb_clock_sync_ccf_sptr (new gr_pfb_clock_sync_ccf (sps, gain, taps,
48 int ios[] = {sizeof(gr_complex), sizeof(float), sizeof(float), sizeof(float)};
49 std::vector<int> iosig(ios, ios+sizeof(ios)/sizeof(int));
50 gr_pfb_clock_sync_ccf::gr_pfb_clock_sync_ccf (double sps, float gain,
51 const std::vector<float> &taps,
52 unsigned int filter_size,
54 float max_rate_deviation)
55 : gr_block ("pfb_clock_sync_ccf",
56 gr_make_io_signature (1, 1, sizeof(gr_complex)),
57 gr_make_io_signaturev (1, 4, iosig)),
58 d_updated (false), d_nfilters(filter_size),
59 d_max_dev(max_rate_deviation)
61 d_nfilters = filter_size;
64 // Store the last filter between calls to work
65 // The accumulator keeps track of overflow to increment the stride correctly.
66 // set it here to the fractional difference based on the initial phaes
68 set_beta(0.25*gain*gain);
70 d_rate = (sps-floor(sps))*(double)d_nfilters;
71 d_filtnum = (int)floor(d_k);
73 d_filters = std::vector<gr_fir_ccf*>(d_nfilters);
74 d_diff_filters = std::vector<gr_fir_ccf*>(d_nfilters);
76 // Create an FIR filter for each channel and zero out the taps
77 std::vector<float> vtaps(0, d_nfilters);
78 for(unsigned int i = 0; i < d_nfilters; i++) {
79 d_filters[i] = gr_fir_util::create_gr_fir_ccf(vtaps);
80 d_diff_filters[i] = gr_fir_util::create_gr_fir_ccf(vtaps);
83 // Now, actually set the filters' taps
84 std::vector<float> dtaps;
85 create_diff_taps(taps, dtaps);
86 set_taps(taps, d_taps, d_filters);
87 set_taps(dtaps, d_dtaps, d_diff_filters);
90 gr_pfb_clock_sync_ccf::~gr_pfb_clock_sync_ccf ()
92 for(unsigned int i = 0; i < d_nfilters; i++) {
98 gr_pfb_clock_sync_ccf::set_taps (const std::vector<float> &newtaps,
99 std::vector< std::vector<float> > &ourtaps,
100 std::vector<gr_fir_ccf*> &ourfilter)
104 unsigned int ntaps = newtaps.size();
105 d_taps_per_filter = (unsigned int)ceil((double)ntaps/(double)d_nfilters);
107 // Create d_numchan vectors to store each channel's taps
108 ourtaps.resize(d_nfilters);
110 // Make a vector of the taps plus fill it out with 0's to fill
111 // each polyphase filter with exactly d_taps_per_filter
112 std::vector<float> tmp_taps;
114 while((float)(tmp_taps.size()) < d_nfilters*d_taps_per_filter) {
115 tmp_taps.push_back(0.0);
118 // Partition the filter
119 for(i = 0; i < d_nfilters; i++) {
120 // Each channel uses all d_taps_per_filter with 0's if not enough taps to fill out
121 //ourtaps[i] = std::vector<float>(d_taps_per_filter, 0);
122 ourtaps[d_nfilters-1-i] = std::vector<float>(d_taps_per_filter, 0);
123 for(j = 0; j < d_taps_per_filter; j++) {
124 ourtaps[d_nfilters - 1 - i][j] = tmp_taps[i + j*d_nfilters];
127 // Build a filter for each channel and add it's taps to it
128 //ourfilter[i]->set_taps(ourtaps[i]);
129 ourfilter[i]->set_taps(ourtaps[d_nfilters-1-i]);
132 // Set the history to ensure enough input items for each filter
133 set_history (d_taps_per_filter + d_sps);
139 gr_pfb_clock_sync_ccf::create_diff_taps(const std::vector<float> &newtaps,
140 std::vector<float> &difftaps)
142 float maxtap = -1e12;
144 difftaps.push_back(0); //newtaps[0]);
145 for(unsigned int i = 1; i < newtaps.size()-1; i++) {
146 float tap = newtaps[i+1] - newtaps[i-1];
151 difftaps.push_back(tap);
153 difftaps.push_back(0);//-newtaps[newtaps.size()-1]);
155 for(unsigned int i = 0; i < difftaps.size(); i++) {
156 difftaps[i] /= 1;//maxtap;
161 gr_pfb_clock_sync_ccf::print_taps()
165 for(i = 0; i < d_nfilters; i++) {
166 printf("[%.4e, ", d_taps[i][0]);
167 for(j = 1; j < d_taps_per_filter-1; j++) {
168 printf("%.4e,", d_taps[i][j]);
170 printf("%.4e],", d_taps[i][j]);
176 gr_pfb_clock_sync_ccf::print_diff_taps()
180 for(i = 0; i < d_nfilters; i++) {
181 printf("[%.4e, ", d_dtaps[i][0]);
182 for(j = 1; j < d_taps_per_filter-1; j++) {
183 printf("%.4e,", d_dtaps[i][j]);
185 printf("%.4e],", d_dtaps[i][j]);
192 gr_pfb_clock_sync_ccf::channel_taps(int channel)
194 std::vector<float> taps;
196 for(i = 0; i < d_taps_per_filter; i++) {
197 taps.push_back(d_taps[channel][i]);
203 gr_pfb_clock_sync_ccf::diff_channel_taps(int channel)
205 std::vector<float> taps;
207 for(i = 0; i < d_taps_per_filter; i++) {
208 taps.push_back(d_dtaps[channel][i]);
215 gr_pfb_clock_sync_ccf::general_work (int noutput_items,
216 gr_vector_int &ninput_items,
217 gr_vector_const_void_star &input_items,
218 gr_vector_void_star &output_items)
220 gr_complex *in = (gr_complex *) input_items[0];
221 gr_complex *out = (gr_complex *) output_items[0];
223 float *err, *outrate, *outk;
224 if(output_items.size() > 2) {
225 err = (float *) output_items[1];
226 outrate = (float*)output_items[2];
227 outk = (float*)output_items[3];
232 return 0; // history requirements may have changed.
235 // We need this many to process one output
236 int nrequired = ninput_items[0] - d_taps_per_filter;
238 int i = 0, count = 0;
239 float error, error_r, error_i;
241 // produce output as long as we can and there are enough input samples
242 while((i < noutput_items) && (count < nrequired)) {
243 d_filtnum = (int)floor(d_k);
245 // Keep the current filter number in [0, d_nfilters]
246 // If we've run beyond the last filter, wrap around and go to next sample
247 // If we've go below 0, wrap around and go to previous sample
248 while(d_filtnum >= d_nfilters) {
250 d_filtnum -= d_nfilters;
253 while(d_filtnum < 0) {
255 d_filtnum += d_nfilters;
259 out[i] = d_filters[d_filtnum]->filter(&in[count]);
260 gr_complex diff = d_diff_filters[d_filtnum]->filter(&in[count]);
261 error_r = out[i].real() * diff.real();
262 error_i = out[i].imag() * diff.imag();
263 error = error_i + error_r;
265 d_k = d_k + d_alpha*error + d_rate;
266 d_rate = d_rate + d_beta*error;
268 // Keep our rate within a good range
269 d_rate = gr_branchless_clip(d_rate, d_max_dev);
272 count += (int)floor(d_sps);
274 if(output_items.size() > 2) {