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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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 (float sps, float gain,
37 const std::vector<float> &taps,
38 unsigned int filter_size,
41 return gr_pfb_clock_sync_ccf_sptr (new gr_pfb_clock_sync_ccf (sps, gain, taps,
46 int ios[] = {sizeof(gr_complex), sizeof(float), sizeof(float), sizeof(float)};
47 std::vector<int> iosig(ios, ios+sizeof(ios)/sizeof(int));
48 gr_pfb_clock_sync_ccf::gr_pfb_clock_sync_ccf (float sps, float gain,
49 const std::vector<float> &taps,
50 unsigned int filter_size,
52 : gr_block ("pfb_clock_sync_ccf",
53 gr_make_io_signature (1, 1, sizeof(gr_complex)),
54 gr_make_io_signaturev (1, 4, iosig)),
55 d_updated (false), d_sps(sps)
57 d_nfilters = filter_size;
59 // Store the last filter between calls to work
60 // The accumulator keeps track of overflow to increment the stride correctly.
61 // set it here to the fractional difference based on the initial phaes
62 // assert(init_phase <= 2*M_PI);
64 set_beta(0.25*gain*gain);
70 d_filters = std::vector<gr_fir_ccf*>(d_nfilters);
71 d_diff_filters = std::vector<gr_fir_ccf*>(d_nfilters);
73 // Create an FIR filter for each channel and zero out the taps
74 std::vector<float> vtaps(0, d_nfilters);
75 for(unsigned int i = 0; i < d_nfilters; i++) {
76 d_filters[i] = gr_fir_util::create_gr_fir_ccf(vtaps);
77 d_diff_filters[i] = gr_fir_util::create_gr_fir_ccf(vtaps);
80 // Now, actually set the filters' taps
81 std::vector<float> dtaps;
82 create_diff_taps(taps, dtaps);
83 set_taps(taps, d_taps, d_filters);
84 set_taps(dtaps, d_dtaps, d_diff_filters);
87 gr_pfb_clock_sync_ccf::~gr_pfb_clock_sync_ccf ()
89 for(unsigned int i = 0; i < d_nfilters; i++) {
95 gr_pfb_clock_sync_ccf::set_taps (const std::vector<float> &newtaps,
96 std::vector< std::vector<float> > &ourtaps,
97 std::vector<gr_fir_ccf*> &ourfilter)
101 unsigned int ntaps = newtaps.size();
102 d_taps_per_filter = (unsigned int)ceil((double)ntaps/(double)d_nfilters);
104 // Create d_numchan vectors to store each channel's taps
105 ourtaps.resize(d_nfilters);
107 // Make a vector of the taps plus fill it out with 0's to fill
108 // each polyphase filter with exactly d_taps_per_filter
109 std::vector<float> tmp_taps;
111 while((float)(tmp_taps.size()) < d_nfilters*d_taps_per_filter) {
112 tmp_taps.push_back(0.0);
115 // Partition the filter
116 for(i = 0; i < d_nfilters; i++) {
117 // Each channel uses all d_taps_per_filter with 0's if not enough taps to fill out
118 //ourtaps[i] = std::vector<float>(d_taps_per_filter, 0);
119 ourtaps[d_nfilters-1-i] = std::vector<float>(d_taps_per_filter, 0);
120 for(j = 0; j < d_taps_per_filter; j++) {
121 ourtaps[d_nfilters - 1 - i][j] = tmp_taps[i + j*d_nfilters];
124 // Build a filter for each channel and add it's taps to it
125 //ourfilter[i]->set_taps(ourtaps[i]);
126 ourfilter[i]->set_taps(ourtaps[d_nfilters-1-i]);
129 // Set the history to ensure enough input items for each filter
130 set_history (d_taps_per_filter + d_sps);
136 gr_pfb_clock_sync_ccf::create_diff_taps(const std::vector<float> &newtaps,
137 std::vector<float> &difftaps)
139 float maxtap = -1e12;
141 difftaps.push_back(0); //newtaps[0]);
142 for(unsigned int i = 1; i < newtaps.size()-1; i++) {
143 float tap = newtaps[i+1] - newtaps[i-1];
148 difftaps.push_back(tap);
150 difftaps.push_back(0);//-newtaps[newtaps.size()-1]);
152 for(unsigned int i = 0; i < difftaps.size(); i++) {
153 difftaps[i] /= 1;//maxtap;
158 gr_pfb_clock_sync_ccf::print_taps()
162 for(i = 0; i < d_nfilters; i++) {
163 printf("[%.4e, ", d_taps[i][0]);
164 for(j = 1; j < d_taps_per_filter-1; j++) {
165 printf("%.4e,", d_taps[i][j]);
167 printf("%.4e],", d_taps[i][j]);
173 gr_pfb_clock_sync_ccf::print_diff_taps()
177 for(i = 0; i < d_nfilters; i++) {
178 printf("[%.4e, ", d_dtaps[i][0]);
179 for(j = 1; j < d_taps_per_filter-1; j++) {
180 printf("%.4e,", d_dtaps[i][j]);
182 printf("%.4e],", d_dtaps[i][j]);
189 gr_pfb_clock_sync_ccf::channel_taps(int channel)
191 std::vector<float> taps;
193 for(i = 0; i < d_taps_per_filter; i++) {
194 taps.push_back(d_taps[channel][i]);
200 gr_pfb_clock_sync_ccf::diff_channel_taps(int channel)
202 std::vector<float> taps;
204 for(i = 0; i < d_taps_per_filter; i++) {
205 taps.push_back(d_dtaps[channel][i]);
212 gr_pfb_clock_sync_ccf::general_work (int noutput_items,
213 gr_vector_int &ninput_items,
214 gr_vector_const_void_star &input_items,
215 gr_vector_void_star &output_items)
217 gr_complex *in = (gr_complex *) input_items[0];
218 gr_complex *out = (gr_complex *) output_items[0];
220 float *err, *outrate, *outk;
221 if(output_items.size() > 2) {
222 err = (float *) output_items[1];
223 outrate = (float*)output_items[2];
224 outk = (float*)output_items[3];
229 return 0; // history requirements may have changed.
232 // We need this many to process one output
233 int nrequired = ninput_items[0] - d_taps_per_filter;
235 int i = 0, count = d_start_count;
238 // produce output as long as we can and there are enough input samples
239 while((i < noutput_items) && (count < nrequired)) {
240 int filtnum = (int)d_k;
242 // FIXME: prevent this from asserting
243 assert(filtnum < d_nfilters);
244 out[i] = d_filters[filtnum]->filter(&in[count]);
245 error = (out[i] * d_diff_filters[filtnum]->filter(&in[count])).real();
247 d_k = d_k + d_alpha*error + d_rate;
248 d_rate = d_rate + d_beta*error;
249 while(d_k >= (float)d_nfilters) {
258 // Keep our rate within a good range
259 d_rate = gr_branchless_clip(d_rate, 1.5);
264 if(output_items.size() > 2) {
270 //printf("error: %f k: %f rate: %f\n",
271 // error, d_k, d_rate);
274 // Set the start index at the next entrance to the work function
275 // if we stop because we run out of input items, jump ahead in the
276 // next call to work. Otherwise, we can start at zero.
277 if(count > nrequired) {
278 d_start_count = count - (nrequired);
279 consume_each(ninput_items[0]-d_taps_per_filter);