3 * Copyright 2009,2010 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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15 * GNU General Public License for more details.
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27 #include <gr_pfb_channelizer_ccf.h>
28 #include <gr_fir_ccf.h>
29 #include <gr_fir_util.h>
31 #include <gr_io_signature.h>
35 gr_pfb_channelizer_ccf_sptr gr_make_pfb_channelizer_ccf (unsigned int numchans,
36 const std::vector<float> &taps,
37 float oversample_rate)
39 return gr_pfb_channelizer_ccf_sptr (new gr_pfb_channelizer_ccf (numchans, taps,
44 gr_pfb_channelizer_ccf::gr_pfb_channelizer_ccf (unsigned int numchans,
45 const std::vector<float> &taps,
46 float oversample_rate)
47 : gr_sync_block ("pfb_channelizer_ccf",
48 gr_make_io_signature (numchans, numchans, sizeof(gr_complex)),
49 gr_make_io_signature (1, 1, numchans*sizeof(gr_complex))),
50 d_updated (false), d_oversample_rate(oversample_rate)
52 d_numchans = numchans;
53 d_filters = std::vector<gr_fir_ccf*>(d_numchans);
55 // Create an FIR filter for each channel and zero out the taps
56 std::vector<float> vtaps(0, d_numchans);
57 for(unsigned int i = 0; i < d_numchans; i++) {
58 d_filters[i] = gr_fir_util::create_gr_fir_ccf(vtaps);
61 // Now, actually set the filters' taps
64 // Create the FFT to handle the output de-spinning of the channels
65 d_fft = new gri_fft_complex (d_numchans, false);
68 gr_pfb_channelizer_ccf::~gr_pfb_channelizer_ccf ()
70 for(unsigned int i = 0; i < d_numchans; i++) {
76 gr_pfb_channelizer_ccf::set_taps (const std::vector<float> &taps)
80 unsigned int ntaps = taps.size();
81 d_taps_per_filter = (unsigned int)ceil((double)ntaps/(double)d_numchans);
83 // Create d_numchan vectors to store each channel's taps
84 d_taps.resize(d_numchans);
86 // Make a vector of the taps plus fill it out with 0's to fill
87 // each polyphase filter with exactly d_taps_per_filter
88 std::vector<float> tmp_taps;
90 while((float)(tmp_taps.size()) < d_numchans*d_taps_per_filter) {
91 tmp_taps.push_back(0.0);
94 // Partition the filter
95 for(i = 0; i < d_numchans; i++) {
96 // Each channel uses all d_taps_per_filter with 0's if not enough taps to fill out
97 d_taps[i] = std::vector<float>(d_taps_per_filter, 0);
98 for(j = 0; j < d_taps_per_filter; j++) {
99 d_taps[i][j] = tmp_taps[i + j*d_numchans]; // add taps to channels in reverse order
102 // Build a filter for each channel and add it's taps to it
103 d_filters[i]->set_taps(d_taps[i]);
106 // Set the history to ensure enough input items for each filter
107 set_history (d_taps_per_filter);
113 gr_pfb_channelizer_ccf::print_taps()
116 for(i = 0; i < d_numchans; i++) {
117 printf("filter[%d]: [", i);
118 for(j = 0; j < d_taps_per_filter; j++) {
119 printf(" %.4e", d_taps[i][j]);
127 gr_pfb_channelizer_ccf::work (int noutput_items,
128 gr_vector_const_void_star &input_items,
129 gr_vector_void_star &output_items)
131 gr_complex *in = (gr_complex *) input_items[0];
132 gr_complex *out = (gr_complex *) output_items[0];
136 return 0; // history requirements may have changed.
139 int M = d_oversample_rate;
145 printf("\nnoutput_items = %d\n", noutput_items);
146 printf("N = %d M = %d r = %d\n", N, M, r);
148 //for(int n = 1; n < noutput_items; n++) {
149 while(n < noutput_items) {
152 //printf("i = %d i >= 0 n = %d\n", i, n);
154 in = (gr_complex*)input_items[j];
155 d_fft->get_inbuf()[i] = d_filters[i]->filter(&in[n]);
161 //printf("i = %d r = %d i >= r\n", i, r);
164 in = (gr_complex*)input_items[j];
165 d_fft->get_inbuf()[i] = d_filters[i]->filter(&in[n-1]);
172 // Move through filters from bottom to top
173 for(int j = d_numchans-1; j >= 0; j--) {
174 // Take in the items from the first input stream to d_numchans
175 in = (gr_complex*)input_items[d_numchans - 1 - j];
177 // Filter current input stream from bottom filter to top
178 d_fft->get_inbuf()[j] = d_filters[j]->filter(&in[i]);
182 // despin through FFT
184 memcpy(&out[d_numchans*n], d_fft->get_outbuf(), d_numchans*sizeof(gr_complex));
185 //memcpy(&out[d_numchans*i], d_fft->get_outbuf(), d_numchans*sizeof(gr_complex));
188 return noutput_items;