piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 1 | /* -*- c++ -*- */ |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 2 | /* |
ptrkrysik | 529895b | 2014-12-02 18:07:38 +0100 | [diff] [blame] | 3 | * @file |
| 4 | * @author Piotr Krysik <ptrkrysik@gmail.com> |
| 5 | * @section LICENSE |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 6 | * |
ptrkrysik | 529895b | 2014-12-02 18:07:38 +0100 | [diff] [blame] | 7 | * Gr-gsm is free software; you can redistribute it and/or modify |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 3, or (at your option) |
| 10 | * any later version. |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 11 | * |
ptrkrysik | 529895b | 2014-12-02 18:07:38 +0100 | [diff] [blame] | 12 | * Gr-gsm is distributed in the hope that it will be useful, |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 16 | * |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 17 | * You should have received a copy of the GNU General Public License |
ptrkrysik | 529895b | 2014-12-02 18:07:38 +0100 | [diff] [blame] | 18 | * along with gr-gsm; see the file COPYING. If not, write to |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 19 | * the Free Software Foundation, Inc., 51 Franklin Street, |
| 20 | * Boston, MA 02110-1301, USA. |
| 21 | */ |
| 22 | |
| 23 | #ifdef HAVE_CONFIG_H |
| 24 | #include "config.h" |
| 25 | #endif |
| 26 | |
| 27 | #include <gnuradio/io_signature.h> |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 28 | #include <gnuradio/math.h> |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 29 | #include <volk/volk.h> |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 30 | #include <math.h> |
| 31 | #include <boost/circular_buffer.hpp> |
| 32 | #include <algorithm> |
| 33 | #include <numeric> |
David Holm | f2497bd | 2014-12-01 21:22:37 +0100 | [diff] [blame] | 34 | #include <vector> |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 35 | #include <viterbi_detector.h> |
| 36 | #include <string.h> |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 37 | #include <iostream> |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 38 | #include <time.h> //!!! |
Piotr Krysik | 0a932e6 | 2016-08-29 07:37:30 +0200 | [diff] [blame] | 39 | //#include <iomanip> |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 40 | #include <boost/scoped_ptr.hpp> |
ptrkrysik | 3be74a7 | 2014-12-13 10:11:00 +0100 | [diff] [blame] | 41 | |
| 42 | #include <sch.h> |
| 43 | #include "receiver_impl.h" |
| 44 | #include <grgsm/endian.h> |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 45 | |
ptrkrysik | d85d460 | 2014-11-13 10:11:53 +0100 | [diff] [blame] | 46 | //files included for debuging |
| 47 | //#include "plotting/plotting.hpp" |
| 48 | //#include <pthread.h> |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 49 | |
| 50 | #define SYNC_SEARCH_RANGE 30 |
| 51 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 52 | namespace gr |
| 53 | { |
| 54 | namespace gsm |
| 55 | { |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 56 | receiver::sptr |
ptrkrysik | 380dea8 | 2015-08-06 10:11:58 +0200 | [diff] [blame] | 57 | receiver::make(int osr, const std::vector<int> &cell_allocation, const std::vector<int> &tseq_nums, bool process_uplink) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 58 | { |
| 59 | return gnuradio::get_initial_sptr |
ptrkrysik | 380dea8 | 2015-08-06 10:11:58 +0200 | [diff] [blame] | 60 | (new receiver_impl(osr, cell_allocation, tseq_nums, process_uplink)); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 61 | } |
| 62 | |
| 63 | /* |
| 64 | * The private constructor |
| 65 | */ |
ptrkrysik | 380dea8 | 2015-08-06 10:11:58 +0200 | [diff] [blame] | 66 | receiver_impl::receiver_impl(int osr, const std::vector<int> &cell_allocation, const std::vector<int> &tseq_nums, bool process_uplink) |
piotr | c7c249a | 2014-05-02 17:24:08 +0200 | [diff] [blame] | 67 | : gr::sync_block("receiver", |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 68 | gr::io_signature::make(1, -1, sizeof(gr_complex)), |
piotr | 7c82b17 | 2014-02-08 14:15:27 +0100 | [diff] [blame] | 69 | gr::io_signature::make(0, 0, 0)), |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 70 | d_OSR(osr), |
ptrkrysik | 380dea8 | 2015-08-06 10:11:58 +0200 | [diff] [blame] | 71 | d_process_uplink(process_uplink), |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 72 | d_chan_imp_length(CHAN_IMP_RESP_LENGTH), |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 73 | d_counter(0), |
| 74 | d_fcch_start_pos(0), |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 75 | d_freq_offset_setting(0), |
piotr | d6d6687 | 2014-08-06 15:20:33 +0200 | [diff] [blame] | 76 | d_state(fcch_search), |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 77 | d_burst_nr(osr), |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 78 | d_failed_sch(0), |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 79 | d_signal_dbm(-120), |
| 80 | d_tseq_nums(tseq_nums), |
ptrkrysik | 32c2116 | 2015-04-04 14:01:52 +0200 | [diff] [blame] | 81 | d_cell_allocation(cell_allocation), |
| 82 | d_last_time(0.0) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 83 | { |
| 84 | int i; |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 85 | //don't send samples to the receiver until there are at least samples for one |
piotr | 7f3f366 | 2014-07-08 16:47:53 +0200 | [diff] [blame] | 86 | set_output_multiple(floor((TS_BITS + 2 * GUARD_PERIOD) * d_OSR)); // burst and two gurad periods (one gurard period is an arbitrary overlap) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 87 | gmsk_mapper(SYNC_BITS, N_SYNC_BITS, d_sch_training_seq, gr_complex(0.0, -1.0)); |
| 88 | for (i = 0; i < TRAIN_SEQ_NUM; i++) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 89 | { |
piotr | f502e0f | 2014-04-24 10:28:29 +0200 | [diff] [blame] | 90 | gr_complex startpoint = (train_seq[i][0]==0) ? gr_complex(1.0, 0.0) : gr_complex(-1.0, 0.0); //if first bit of the seqeunce ==0 first symbol ==1 |
piotr | 7f3f366 | 2014-07-08 16:47:53 +0200 | [diff] [blame] | 91 | //if first bit of the seqeunce ==1 first symbol ==-1 |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 92 | gmsk_mapper(train_seq[i], N_TRAIN_BITS, d_norm_training_seq[i], startpoint); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 93 | } |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 94 | message_port_register_out(pmt::mp("C0")); |
| 95 | message_port_register_out(pmt::mp("CX")); |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 96 | message_port_register_out(pmt::mp("measurements")); |
piotr | 903b1d6 | 2014-04-17 11:33:27 +0200 | [diff] [blame] | 97 | configure_receiver(); //configure the receiver - tell it where to find which burst type |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 98 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 99 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 100 | /* |
| 101 | * Our virtual destructor. |
| 102 | */ |
| 103 | receiver_impl::~receiver_impl() |
| 104 | { |
| 105 | } |
| 106 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 107 | int |
piotr | c7c249a | 2014-05-02 17:24:08 +0200 | [diff] [blame] | 108 | receiver_impl::work(int noutput_items, |
| 109 | gr_vector_const_void_star &input_items, |
| 110 | gr_vector_void_star &output_items) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 111 | { |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 112 | // std::vector<const gr_complex *> iii = (std::vector<const gr_complex *>) input_items; // jak zrobić to rzutowanie poprawnie |
| 113 | gr_complex * input = (gr_complex *) input_items[0]; |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 114 | std::vector<tag_t> freq_offset_tags; |
| 115 | uint64_t start = nitems_read(0); |
| 116 | uint64_t stop = start + noutput_items; |
piotr | 7c82b17 | 2014-02-08 14:15:27 +0100 | [diff] [blame] | 117 | |
ptrkrysik | 32c2116 | 2015-04-04 14:01:52 +0200 | [diff] [blame] | 118 | float current_time = static_cast<float>(start)/(GSM_SYMBOL_RATE*d_OSR); |
| 119 | if((current_time - d_last_time) > 0.1) |
| 120 | { |
| 121 | pmt::pmt_t msg = pmt::make_tuple(pmt::mp("current_time"),pmt::from_double(current_time)); |
| 122 | message_port_pub(pmt::mp("measurements"), msg); |
| 123 | d_last_time = current_time; |
| 124 | } |
| 125 | |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 126 | pmt::pmt_t key = pmt::string_to_symbol("setting_freq_offset"); |
| 127 | get_tags_in_range(freq_offset_tags, 0, start, stop, key); |
| 128 | bool freq_offset_tag_in_fcch = false; |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 129 | |
| 130 | if(!freq_offset_tags.empty()){ |
| 131 | tag_t freq_offset_tag = freq_offset_tags[0]; |
Piotr Krysik | 43af70d | 2016-07-20 21:37:24 +0200 | [diff] [blame] | 132 | uint64_t tag_offset = freq_offset_tag.offset - start; |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 133 | |
| 134 | burst_type b_type = d_channel_conf.get_burst_type(d_burst_nr); |
| 135 | if(d_state == synchronized && b_type == fcch_burst){ |
| 136 | uint64_t last_sample_nr = ceil((GUARD_PERIOD + 2.0 * TAIL_BITS + 156.25) * d_OSR) + 1; |
| 137 | if(tag_offset < last_sample_nr){ |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 138 | freq_offset_tag_in_fcch = true; |
| 139 | } |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 140 | } |
Piotr Krysik | 43af70d | 2016-07-20 21:37:24 +0200 | [diff] [blame] | 141 | d_freq_offset_setting = pmt::to_double(freq_offset_tag.value); |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 142 | } |
| 143 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 144 | switch (d_state) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 145 | { |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 146 | //bootstrapping |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 147 | case fcch_search: |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 148 | { |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 149 | double freq_offset_tmp; |
| 150 | if (find_fcch_burst(input, noutput_items,freq_offset_tmp)) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 151 | { |
piotr | d6d6687 | 2014-08-06 15:20:33 +0200 | [diff] [blame] | 152 | pmt::pmt_t msg = pmt::make_tuple(pmt::mp("freq_offset"),pmt::from_double(freq_offset_tmp-d_freq_offset_setting),pmt::mp("fcch_search")); |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 153 | message_port_pub(pmt::mp("measurements"), msg); |
| 154 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 155 | d_state = sch_search; |
| 156 | } |
| 157 | else |
| 158 | { |
piotr | d6d6687 | 2014-08-06 15:20:33 +0200 | [diff] [blame] | 159 | d_state = fcch_search; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 160 | } |
| 161 | break; |
| 162 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 163 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 164 | case sch_search: |
| 165 | { |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 166 | std::vector<gr_complex> channel_imp_resp(CHAN_IMP_RESP_LENGTH*d_OSR); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 167 | int t1, t2, t3; |
| 168 | int burst_start = 0; |
| 169 | unsigned char output_binary[BURST_SIZE]; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 170 | |
piotr | c7c249a | 2014-05-02 17:24:08 +0200 | [diff] [blame] | 171 | if (reach_sch_burst(noutput_items)) //wait for a SCH burst |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 172 | { |
| 173 | burst_start = get_sch_chan_imp_resp(input, &channel_imp_resp[0]); //get channel impulse response from it |
| 174 | detect_burst(input, &channel_imp_resp[0], burst_start, output_binary); //detect bits using MLSE detection |
| 175 | if (decode_sch(&output_binary[3], &t1, &t2, &t3, &d_ncc, &d_bcc) == 0) //decode SCH burst |
| 176 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 177 | d_burst_nr.set(t1, t2, t3, 0); //set counter of bursts value |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 178 | d_burst_nr++; |
| 179 | |
piotr | 7f3f366 | 2014-07-08 16:47:53 +0200 | [diff] [blame] | 180 | consume_each(burst_start + BURST_SIZE * d_OSR + 4*d_OSR); //consume samples up to next guard period |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 181 | d_state = synchronized; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 182 | } |
| 183 | else |
| 184 | { |
piotr | d6d6687 | 2014-08-06 15:20:33 +0200 | [diff] [blame] | 185 | d_state = fcch_search; //if there is error in the sch burst go back to fcch search phase |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 186 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 187 | } |
| 188 | else |
| 189 | { |
| 190 | d_state = sch_search; |
| 191 | } |
| 192 | break; |
| 193 | } |
| 194 | //in this state receiver is synchronized and it processes bursts according to burst type for given burst number |
| 195 | case synchronized: |
| 196 | { |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 197 | std::vector<gr_complex> channel_imp_resp(CHAN_IMP_RESP_LENGTH*d_OSR); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 198 | int offset = 0; |
| 199 | int to_consume = 0; |
| 200 | unsigned char output_binary[BURST_SIZE]; |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 201 | burst_type b_type; |
ptrkrysik | 380dea8 | 2015-08-06 10:11:58 +0200 | [diff] [blame] | 202 | unsigned int inputs_to_process=d_cell_allocation.size(); |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 203 | |
ptrkrysik | 380dea8 | 2015-08-06 10:11:58 +0200 | [diff] [blame] | 204 | if(d_process_uplink) |
| 205 | { |
| 206 | inputs_to_process = 2*inputs_to_process; |
| 207 | } |
| 208 | |
| 209 | for(int input_nr=0; input_nr<inputs_to_process; input_nr++) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 210 | { |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 211 | double signal_pwr = 0; |
| 212 | input = (gr_complex *)input_items[input_nr]; |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 213 | |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 214 | for(int ii=GUARD_PERIOD;ii<TS_BITS;ii++) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 215 | { |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 216 | signal_pwr += abs(input[ii])*abs(input[ii]); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 217 | } |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 218 | signal_pwr = signal_pwr/(TS_BITS); |
| 219 | d_signal_dbm = round(10*log10(signal_pwr/50)); |
| 220 | if(input_nr==0){ |
| 221 | d_c0_signal_dbm = d_signal_dbm; |
| 222 | } |
| 223 | |
| 224 | if(input_nr==0) //for c0 channel burst type is controlled by channel configuration |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 225 | { |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 226 | b_type = d_channel_conf.get_burst_type(d_burst_nr); //get burst type for given burst number |
| 227 | } |
| 228 | else |
| 229 | { |
| 230 | b_type = normal_or_noise; //for the rest it can be only normal burst or noise (at least at this moment of development) |
| 231 | } |
| 232 | |
| 233 | switch (b_type) |
| 234 | { |
| 235 | case fcch_burst: //if it's FCCH burst |
| 236 | { |
Piotr Krysik | 43af70d | 2016-07-20 21:37:24 +0200 | [diff] [blame] | 237 | if(freq_offset_tag_in_fcch==false) |
| 238 | { |
| 239 | const unsigned first_sample = ceil((GUARD_PERIOD + 2 * TAIL_BITS) * d_OSR) + 1; |
| 240 | const unsigned last_sample = first_sample + USEFUL_BITS * d_OSR - TAIL_BITS * d_OSR; |
| 241 | double freq_offset_tmp = compute_freq_offset(input, first_sample, last_sample); //extract frequency offset from it |
Piotr Krysik | 43af70d | 2016-07-20 21:37:24 +0200 | [diff] [blame] | 242 | send_burst(d_burst_nr, fc_fb, GSMTAP_BURST_FCCH, input_nr); |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 243 | |
Piotr Krysik | 43af70d | 2016-07-20 21:37:24 +0200 | [diff] [blame] | 244 | pmt::pmt_t msg = pmt::make_tuple(pmt::mp("freq_offset"),pmt::from_double(freq_offset_tmp-d_freq_offset_setting),pmt::mp("synchronized")); |
| 245 | message_port_pub(pmt::mp("measurements"), msg); |
| 246 | } |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 247 | break; |
| 248 | } |
| 249 | case sch_burst: //if it's SCH burst |
| 250 | { |
| 251 | int t1, t2, t3, d_ncc, d_bcc; |
| 252 | d_c0_burst_start = get_sch_chan_imp_resp(input, &channel_imp_resp[0]); //get channel impulse response |
| 253 | |
| 254 | detect_burst(input, &channel_imp_resp[0], d_c0_burst_start, output_binary); //MLSE detection of bits |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 255 | send_burst(d_burst_nr, output_binary, GSMTAP_BURST_SCH, input_nr); |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 256 | if (decode_sch(&output_binary[3], &t1, &t2, &t3, &d_ncc, &d_bcc) == 0) //and decode SCH data |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 257 | { |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 258 | // d_burst_nr.set(t1, t2, t3, 0); //but only to check if burst_start value is correct |
| 259 | d_failed_sch = 0; |
| 260 | offset = d_c0_burst_start - floor((GUARD_PERIOD) * d_OSR); //compute offset from burst_start - burst should start after a guard period |
| 261 | to_consume += offset; //adjust with offset number of samples to be consumed |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 262 | } |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 263 | else |
| 264 | { |
| 265 | d_failed_sch++; |
| 266 | if (d_failed_sch >= MAX_SCH_ERRORS) |
| 267 | { |
| 268 | d_state = fcch_search; |
| 269 | pmt::pmt_t msg = pmt::make_tuple(pmt::mp("freq_offset"),pmt::from_double(0.0),pmt::mp("sync_loss")); |
| 270 | message_port_pub(pmt::mp("measurements"), msg); |
ptrkrysik | d57745d | 2014-12-02 19:05:36 +0100 | [diff] [blame] | 271 | //DCOUT("Re-Synchronization!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"); |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 272 | } |
| 273 | } |
| 274 | break; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 275 | } |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 276 | case normal_burst: |
| 277 | { |
| 278 | float normal_corr_max; //if it's normal burst |
| 279 | d_c0_burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], &normal_corr_max, d_bcc); //get channel impulse response for given training sequence number - d_bcc |
| 280 | detect_burst(input, &channel_imp_resp[0], d_c0_burst_start, output_binary); //MLSE detection of bits |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 281 | send_burst(d_burst_nr, output_binary, GSMTAP_BURST_NORMAL, input_nr); |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 282 | break; |
| 283 | } |
| 284 | case dummy_or_normal: |
| 285 | { |
| 286 | unsigned int normal_burst_start, dummy_burst_start; |
| 287 | float dummy_corr_max, normal_corr_max; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 288 | |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 289 | dummy_burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], &dummy_corr_max, TS_DUMMY); |
| 290 | normal_burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], &normal_corr_max, d_bcc); |
Piotr Krysik | 9bc0fc0 | 2017-01-18 21:53:17 +0100 | [diff] [blame^] | 291 | |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 292 | if (normal_corr_max > dummy_corr_max) |
| 293 | { |
| 294 | d_c0_burst_start = normal_burst_start; |
| 295 | detect_burst(input, &channel_imp_resp[0], normal_burst_start, output_binary); |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 296 | send_burst(d_burst_nr, output_binary, GSMTAP_BURST_NORMAL, input_nr); |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 297 | } |
| 298 | else |
| 299 | { |
| 300 | d_c0_burst_start = dummy_burst_start; |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 301 | send_burst(d_burst_nr, dummy_burst, GSMTAP_BURST_DUMMY, input_nr); |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 302 | } |
| 303 | break; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 304 | } |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 305 | case rach_burst: |
| 306 | break; |
| 307 | case dummy: |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 308 | send_burst(d_burst_nr, dummy_burst, GSMTAP_BURST_DUMMY, input_nr); |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 309 | break; |
| 310 | case normal_or_noise: |
| 311 | { |
| 312 | unsigned int burst_start; |
| 313 | float normal_corr_max_tmp; |
| 314 | float normal_corr_max=-1e6; |
| 315 | int max_tn; |
| 316 | std::vector<gr_complex> v(input, input + noutput_items); |
Piotr Krysik | f0ec659 | 2016-03-11 09:05:46 +0100 | [diff] [blame] | 317 | //if(d_signal_dbm>=d_c0_signal_dbm-13) |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 318 | { |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 319 | if(d_tseq_nums.size()==0) //there is no information about training sequence |
| 320 | { //however the receiver can detect it |
| 321 | get_norm_chan_imp_resp(input, &channel_imp_resp[0], &normal_corr_max, 0); |
| 322 | float ts_max=normal_corr_max; //with use of a very simple algorithm based on finding |
| 323 | int ts_max_num=0; //maximum correlation |
| 324 | for(int ss=1; ss<=7; ss++) |
| 325 | { |
| 326 | get_norm_chan_imp_resp(input, &channel_imp_resp[0], &normal_corr_max, ss); |
| 327 | if(ts_max<normal_corr_max) |
| 328 | { |
| 329 | ts_max = normal_corr_max; |
| 330 | ts_max_num = ss; |
| 331 | } |
| 332 | } |
| 333 | d_tseq_nums.push_back(ts_max_num); |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 334 | } |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 335 | int tseq_num; |
Piotr Krysik | f0ec659 | 2016-03-11 09:05:46 +0100 | [diff] [blame] | 336 | if(input_nr<=d_tseq_nums.size()) |
| 337 | { |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 338 | tseq_num = d_tseq_nums[input_nr-1]; |
Piotr Krysik | f0ec659 | 2016-03-11 09:05:46 +0100 | [diff] [blame] | 339 | } else |
| 340 | { |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 341 | tseq_num = d_tseq_nums.back(); |
| 342 | } |
| 343 | burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], &normal_corr_max, tseq_num); |
| 344 | // if(abs(d_c0_burst_start-burst_start)<=2){ //unused check/filter based on timing |
Piotr Krysik | f0ec659 | 2016-03-11 09:05:46 +0100 | [diff] [blame] | 345 | // if((normal_corr_max/sqrt(signal_pwr))>=0.9) |
| 346 | { |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 347 | detect_burst(input, &channel_imp_resp[0], burst_start, output_binary); |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 348 | send_burst(d_burst_nr, output_binary, GSMTAP_BURST_NORMAL, input_nr); |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 349 | } |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 350 | } |
| 351 | break; |
| 352 | } |
| 353 | case empty: //if it's empty burst |
| 354 | break; //do nothing |
| 355 | } |
| 356 | |
ptrkrysik | 91c2835 | 2015-06-07 18:36:15 +0200 | [diff] [blame] | 357 | if(input_nr==input_items.size()-1) |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 358 | { |
| 359 | d_burst_nr++; //go to next burst |
| 360 | to_consume += TS_BITS * d_OSR + d_burst_nr.get_offset(); //consume samples of the burst up to next guard period |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 361 | consume_each(to_consume); |
| 362 | } |
| 363 | //and add offset which is introduced by |
| 364 | //0.25 fractional part of a guard period |
| 365 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 366 | } |
| 367 | break; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 368 | } |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 369 | return 0; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 370 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 371 | |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 372 | bool receiver_impl::find_fcch_burst(const gr_complex *input, const int nitems, double & computed_freq_offset) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 373 | { |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 374 | boost::circular_buffer<float> phase_diff_buffer(FCCH_HITS_NEEDED * d_OSR); //circular buffer used to scan throug signal to find |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 375 | //best match for FCCH burst |
| 376 | float phase_diff = 0; |
| 377 | gr_complex conjprod; |
| 378 | int start_pos = -1; |
| 379 | int hit_count = 0; |
| 380 | int miss_count = 0; |
| 381 | float min_phase_diff; |
| 382 | float max_phase_diff; |
| 383 | double best_sum = 0; |
| 384 | float lowest_max_min_diff = 99999; |
| 385 | |
| 386 | int to_consume = 0; |
| 387 | int sample_number = 0; |
| 388 | bool end = false; |
| 389 | bool result = false; |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 390 | boost::circular_buffer<float>::iterator buffer_iter; |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 391 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 392 | /**@name Possible states of FCCH search algorithm*/ |
| 393 | //@{ |
| 394 | enum states |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 395 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 396 | init, ///< initialize variables |
| 397 | search, ///< search for positive samples |
| 398 | found_something, ///< search for FCCH and the best position of it |
| 399 | fcch_found, ///< when FCCH was found |
| 400 | search_fail ///< when there is no FCCH in the input vector |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 401 | } fcch_search_state; |
| 402 | //@} |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 403 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 404 | fcch_search_state = init; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 405 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 406 | while (!end) |
| 407 | { |
| 408 | switch (fcch_search_state) |
| 409 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 410 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 411 | case init: //initialize variables |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 412 | hit_count = 0; |
| 413 | miss_count = 0; |
| 414 | start_pos = -1; |
| 415 | lowest_max_min_diff = 99999; |
| 416 | phase_diff_buffer.clear(); |
| 417 | fcch_search_state = search; |
| 418 | |
| 419 | break; |
| 420 | |
piotr | 7c82b17 | 2014-02-08 14:15:27 +0100 | [diff] [blame] | 421 | case search: // search for positive samples |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 422 | sample_number++; |
| 423 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 424 | if (sample_number > nitems - FCCH_HITS_NEEDED * d_OSR) //if it isn't possible to find FCCH because |
| 425 | { |
piotr | 7c82b17 | 2014-02-08 14:15:27 +0100 | [diff] [blame] | 426 | //there's too few samples left to look into, |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 427 | to_consume = sample_number; //don't do anything with those samples which are left |
piotr | 7c82b17 | 2014-02-08 14:15:27 +0100 | [diff] [blame] | 428 | //and consume only those which were checked |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 429 | fcch_search_state = search_fail; |
| 430 | } |
| 431 | else |
| 432 | { |
| 433 | phase_diff = compute_phase_diff(input[sample_number], input[sample_number-1]); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 434 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 435 | if (phase_diff > 0) //if a positive phase difference was found |
| 436 | { |
| 437 | to_consume = sample_number; |
| 438 | fcch_search_state = found_something; //switch to state in which searches for FCCH |
| 439 | } |
| 440 | else |
| 441 | { |
| 442 | fcch_search_state = search; |
| 443 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 444 | } |
| 445 | |
| 446 | break; |
| 447 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 448 | case found_something: // search for FCCH and the best position of it |
| 449 | { |
| 450 | if (phase_diff > 0) |
| 451 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 452 | hit_count++; //positive phase differencies increases hits_count |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 453 | } |
| 454 | else |
| 455 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 456 | miss_count++; //negative increases miss_count |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 457 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 458 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 459 | if ((miss_count >= FCCH_MAX_MISSES * d_OSR) && (hit_count <= FCCH_HITS_NEEDED * d_OSR)) |
| 460 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 461 | //if miss_count exceeds limit before hit_count |
| 462 | fcch_search_state = init; //go to init |
| 463 | continue; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 464 | } |
| 465 | else if (((miss_count >= FCCH_MAX_MISSES * d_OSR) && (hit_count > FCCH_HITS_NEEDED * d_OSR)) || (hit_count > 2 * FCCH_HITS_NEEDED * d_OSR)) |
| 466 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 467 | //if hit_count and miss_count exceeds limit then FCCH was found |
| 468 | fcch_search_state = fcch_found; |
| 469 | continue; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 470 | } |
| 471 | else if ((miss_count < FCCH_MAX_MISSES * d_OSR) && (hit_count > FCCH_HITS_NEEDED * d_OSR)) |
| 472 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 473 | //find difference between minimal and maximal element in the buffer |
| 474 | //for FCCH this value should be low |
| 475 | //this part is searching for a region where this value is lowest |
| 476 | min_phase_diff = * (min_element(phase_diff_buffer.begin(), phase_diff_buffer.end())); |
| 477 | max_phase_diff = * (max_element(phase_diff_buffer.begin(), phase_diff_buffer.end())); |
| 478 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 479 | if (lowest_max_min_diff > max_phase_diff - min_phase_diff) |
| 480 | { |
| 481 | lowest_max_min_diff = max_phase_diff - min_phase_diff; |
| 482 | start_pos = sample_number - FCCH_HITS_NEEDED * d_OSR - FCCH_MAX_MISSES * d_OSR; //store start pos |
| 483 | best_sum = 0; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 484 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 485 | for (buffer_iter = phase_diff_buffer.begin(); |
| 486 | buffer_iter != (phase_diff_buffer.end()); |
| 487 | buffer_iter++) |
| 488 | { |
| 489 | best_sum += *buffer_iter - (M_PI / 2) / d_OSR; //store best value of phase offset sum |
| 490 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 491 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 492 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 493 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 494 | sample_number++; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 495 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 496 | if (sample_number >= nitems) //if there's no single sample left to check |
| 497 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 498 | fcch_search_state = search_fail;//FCCH search failed |
| 499 | continue; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 500 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 501 | |
| 502 | phase_diff = compute_phase_diff(input[sample_number], input[sample_number-1]); |
| 503 | phase_diff_buffer.push_back(phase_diff); |
| 504 | fcch_search_state = found_something; |
| 505 | } |
| 506 | break; |
| 507 | |
| 508 | case fcch_found: |
| 509 | { |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 510 | to_consume = start_pos + FCCH_HITS_NEEDED * d_OSR + 1; //consume one FCCH burst |
| 511 | |
| 512 | d_fcch_start_pos = d_counter + start_pos; |
| 513 | |
| 514 | //compute frequency offset |
| 515 | double phase_offset = best_sum / FCCH_HITS_NEEDED; |
piotr | 4089c1a | 2014-08-06 14:10:56 +0200 | [diff] [blame] | 516 | double freq_offset = phase_offset * 1625000.0/6 / (2 * M_PI); //1625000.0/6 - GMSK symbol rate in GSM |
| 517 | computed_freq_offset = freq_offset; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 518 | |
| 519 | end = true; |
| 520 | result = true; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 521 | break; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 522 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 523 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 524 | case search_fail: |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 525 | end = true; |
| 526 | result = false; |
| 527 | break; |
| 528 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 529 | } |
| 530 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 531 | d_counter += to_consume; |
| 532 | consume_each(to_consume); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 533 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 534 | return result; |
| 535 | } |
| 536 | |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 537 | double receiver_impl::estim_freq_norm(const gr_complex * input, unsigned first_sample, unsigned last_sample) //another frequency estimator |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 538 | { |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 539 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 540 | unsigned ii; |
| 541 | |
Piotr Krysik | 9bc0fc0 | 2017-01-18 21:53:17 +0100 | [diff] [blame^] | 542 | double sum = 0; |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 543 | |
Piotr Krysik | 9bc0fc0 | 2017-01-18 21:53:17 +0100 | [diff] [blame^] | 544 | for (ii = first_sample; ii < last_sample-1; ii++) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 545 | { |
Piotr Krysik | 9bc0fc0 | 2017-01-18 21:53:17 +0100 | [diff] [blame^] | 546 | sum += fast_atan2f(input[ii+1] * conj(input[ii])); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 547 | } |
Piotr Krysik | 9bc0fc0 | 2017-01-18 21:53:17 +0100 | [diff] [blame^] | 548 | int N = last_sample-1-first_sample; |
| 549 | return sum/(2*M_PI)/N * d_OSR; |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 550 | } |
| 551 | |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 552 | double receiver_impl::compute_freq_offset(const gr_complex * input, unsigned first_sample, unsigned last_sample) |
| 553 | { |
Piotr Krysik | 9bc0fc0 | 2017-01-18 21:53:17 +0100 | [diff] [blame^] | 554 | float freq_norm = estim_freq_norm(input, first_sample, last_sample); |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 555 | float freq_offset = (freq_norm - 0.25) * 1625000.0/6.0; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 556 | return freq_offset; |
| 557 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 558 | |
Piotr Krysik | d61f85b | 2016-08-29 07:38:25 +0200 | [diff] [blame] | 559 | //double receiver_impl::compute_freq_offset(const gr_complex * input, unsigned first_sample, unsigned last_sample) |
| 560 | //{ |
| 561 | // double phase_sum = 0; |
| 562 | // unsigned ii; |
| 563 | |
| 564 | // for (ii = first_sample; ii < last_sample; ii++) |
| 565 | // { |
| 566 | // double phase_diff = compute_phase_diff(input[ii], input[ii-1]) - (M_PI / 2) / d_OSR; |
| 567 | // phase_sum += phase_diff; |
| 568 | // } |
| 569 | |
| 570 | // double phase_offset = phase_sum / (last_sample - first_sample); |
| 571 | // double freq_offset = phase_offset * 1625000.0 / (12.0 * M_PI); |
| 572 | // return freq_offset; |
| 573 | //} |
| 574 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 575 | inline float receiver_impl::compute_phase_diff(gr_complex val1, gr_complex val2) |
| 576 | { |
| 577 | gr_complex conjprod = val1 * conj(val2); |
| 578 | return fast_atan2f(imag(conjprod), real(conjprod)); |
| 579 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 580 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 581 | bool receiver_impl::reach_sch_burst(const int nitems) |
| 582 | { |
| 583 | //it just consumes samples to get near to a SCH burst |
| 584 | int to_consume = 0; |
| 585 | bool result = false; |
| 586 | unsigned sample_nr_near_sch_start = d_fcch_start_pos + (FRAME_BITS - SAFETY_MARGIN) * d_OSR; |
| 587 | |
| 588 | //consume samples until d_counter will be equal to sample_nr_near_sch_start |
| 589 | if (d_counter < sample_nr_near_sch_start) |
| 590 | { |
| 591 | if (d_counter + nitems >= sample_nr_near_sch_start) |
| 592 | { |
| 593 | to_consume = sample_nr_near_sch_start - d_counter; |
| 594 | } |
| 595 | else |
| 596 | { |
| 597 | to_consume = nitems; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 598 | } |
| 599 | result = false; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 600 | } |
| 601 | else |
| 602 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 603 | to_consume = 0; |
| 604 | result = true; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 605 | } |
| 606 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 607 | d_counter += to_consume; |
| 608 | consume_each(to_consume); |
| 609 | return result; |
| 610 | } |
| 611 | |
| 612 | int receiver_impl::get_sch_chan_imp_resp(const gr_complex *input, gr_complex * chan_imp_resp) |
| 613 | { |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 614 | std::vector<gr_complex> correlation_buffer; |
| 615 | std::vector<float> power_buffer; |
| 616 | std::vector<float> window_energy_buffer; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 617 | |
| 618 | int strongest_window_nr; |
| 619 | int burst_start = 0; |
| 620 | int chan_imp_resp_center = 0; |
| 621 | float max_correlation = 0; |
| 622 | float energy = 0; |
| 623 | |
| 624 | for (int ii = SYNC_POS * d_OSR; ii < (SYNC_POS + SYNC_SEARCH_RANGE) *d_OSR; ii++) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 625 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 626 | gr_complex correlation = correlate_sequence(&d_sch_training_seq[5], N_SYNC_BITS - 10, &input[ii]); |
| 627 | correlation_buffer.push_back(correlation); |
| 628 | power_buffer.push_back(std::pow(abs(correlation), 2)); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 629 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 630 | //compute window energies |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 631 | std::vector<float>::iterator iter = power_buffer.begin(); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 632 | bool loop_end = false; |
| 633 | while (iter != power_buffer.end()) |
| 634 | { |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 635 | std::vector<float>::iterator iter_ii = iter; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 636 | energy = 0; |
| 637 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 638 | for (int ii = 0; ii < (d_chan_imp_length) *d_OSR; ii++, iter_ii++) |
| 639 | { |
| 640 | if (iter_ii == power_buffer.end()) |
| 641 | { |
| 642 | loop_end = true; |
| 643 | break; |
| 644 | } |
| 645 | energy += (*iter_ii); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 646 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 647 | if (loop_end) |
| 648 | { |
| 649 | break; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 650 | } |
| 651 | iter++; |
| 652 | window_energy_buffer.push_back(energy); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 653 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 654 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 655 | strongest_window_nr = max_element(window_energy_buffer.begin(), window_energy_buffer.end()) - window_energy_buffer.begin(); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 656 | // d_channel_imp_resp.clear(); |
| 657 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 658 | max_correlation = 0; |
| 659 | for (int ii = 0; ii < (d_chan_imp_length) *d_OSR; ii++) |
| 660 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 661 | gr_complex correlation = correlation_buffer[strongest_window_nr + ii]; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 662 | if (abs(correlation) > max_correlation) |
| 663 | { |
| 664 | chan_imp_resp_center = ii; |
| 665 | max_correlation = abs(correlation); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 666 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 667 | // d_channel_imp_resp.push_back(correlation); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 668 | chan_imp_resp[ii] = correlation; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 669 | } |
| 670 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 671 | burst_start = strongest_window_nr + chan_imp_resp_center - 48 * d_OSR - 2 * d_OSR + 2 + SYNC_POS * d_OSR; |
| 672 | return burst_start; |
| 673 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 674 | |
| 675 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 676 | void receiver_impl::detect_burst(const gr_complex * input, gr_complex * chan_imp_resp, int burst_start, unsigned char * output_binary) |
| 677 | { |
| 678 | float output[BURST_SIZE]; |
David Holm | f2497bd | 2014-12-01 21:22:37 +0100 | [diff] [blame] | 679 | std::vector<gr_complex> rhh_temp(CHAN_IMP_RESP_LENGTH*d_OSR); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 680 | gr_complex rhh[CHAN_IMP_RESP_LENGTH]; |
| 681 | gr_complex filtered_burst[BURST_SIZE]; |
| 682 | int start_state = 3; |
| 683 | unsigned int stop_states[2] = {4, 12}; |
| 684 | |
David Holm | f2497bd | 2014-12-01 21:22:37 +0100 | [diff] [blame] | 685 | autocorrelation(chan_imp_resp, &rhh_temp[0], d_chan_imp_length*d_OSR); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 686 | for (int ii = 0; ii < (d_chan_imp_length); ii++) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 687 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 688 | rhh[ii] = conj(rhh_temp[ii*d_OSR]); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 689 | } |
| 690 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 691 | mafi(&input[burst_start], BURST_SIZE, chan_imp_resp, d_chan_imp_length*d_OSR, filtered_burst); |
| 692 | |
| 693 | viterbi_detector(filtered_burst, BURST_SIZE, rhh, start_state, stop_states, 2, output); |
| 694 | |
| 695 | for (int i = 0; i < BURST_SIZE ; i++) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 696 | { |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 697 | output_binary[i] = (output[i] > 0); |
| 698 | } |
| 699 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 700 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 701 | void receiver_impl::gmsk_mapper(const unsigned char * input, int nitems, gr_complex * gmsk_output, gr_complex start_point) |
| 702 | { |
| 703 | gr_complex j = gr_complex(0.0, 1.0); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 704 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 705 | int current_symbol; |
| 706 | int encoded_symbol; |
| 707 | int previous_symbol = 2 * input[0] - 1; |
| 708 | gmsk_output[0] = start_point; |
| 709 | |
| 710 | for (int i = 1; i < nitems; i++) |
| 711 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 712 | //change bits representation to NRZ |
| 713 | current_symbol = 2 * input[i] - 1; |
| 714 | //differentially encode |
| 715 | encoded_symbol = current_symbol * previous_symbol; |
| 716 | //and do gmsk mapping |
| 717 | gmsk_output[i] = j * gr_complex(encoded_symbol, 0.0) * gmsk_output[i-1]; |
| 718 | previous_symbol = current_symbol; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 719 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 720 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 721 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 722 | gr_complex receiver_impl::correlate_sequence(const gr_complex * sequence, int length, const gr_complex * input) |
| 723 | { |
| 724 | gr_complex result(0.0, 0.0); |
| 725 | int sample_number = 0; |
| 726 | |
| 727 | for (int ii = 0; ii < length; ii++) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 728 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 729 | sample_number = (ii * d_OSR) ; |
| 730 | result += sequence[ii] * conj(input[sample_number]); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 731 | } |
| 732 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 733 | result = result / gr_complex(length, 0); |
| 734 | return result; |
| 735 | } |
| 736 | |
| 737 | //computes autocorrelation for positive arguments |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 738 | inline void receiver_impl::autocorrelation(const gr_complex * input, gr_complex * out, int nitems) |
| 739 | { |
| 740 | int i, k; |
| 741 | for (k = nitems - 1; k >= 0; k--) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 742 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 743 | out[k] = gr_complex(0, 0); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 744 | for (i = k; i < nitems; i++) |
| 745 | { |
| 746 | out[k] += input[i] * conj(input[i-k]); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 747 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 748 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 749 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 750 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 751 | inline void receiver_impl::mafi(const gr_complex * input, int nitems, gr_complex * filter, int filter_length, gr_complex * output) |
| 752 | { |
| 753 | int ii = 0, n, a; |
| 754 | |
| 755 | for (n = 0; n < nitems; n++) |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 756 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 757 | a = n * d_OSR; |
| 758 | output[n] = 0; |
| 759 | ii = 0; |
| 760 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 761 | while (ii < filter_length) |
| 762 | { |
piotr | da8a066 | 2014-04-24 10:29:38 +0200 | [diff] [blame] | 763 | if ((a + ii) >= nitems*d_OSR){ |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 764 | break; |
piotr | da8a066 | 2014-04-24 10:29:38 +0200 | [diff] [blame] | 765 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 766 | output[n] += input[a+ii] * filter[ii]; |
| 767 | ii++; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 768 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 769 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 770 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 771 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 772 | //especially computations of strongest_window_nr |
piotr | 7e3b0db | 2014-02-05 22:44:30 +0100 | [diff] [blame] | 773 | int receiver_impl::get_norm_chan_imp_resp(const gr_complex *input, gr_complex * chan_imp_resp, float *corr_max, int bcc) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 774 | { |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 775 | std::vector<gr_complex> correlation_buffer; |
| 776 | std::vector<float> power_buffer; |
| 777 | std::vector<float> window_energy_buffer; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 778 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 779 | int strongest_window_nr; |
| 780 | int burst_start = 0; |
| 781 | int chan_imp_resp_center = 0; |
| 782 | float max_correlation = 0; |
| 783 | float energy = 0; |
piotr | 5c82025 | 2014-04-17 09:43:02 +0200 | [diff] [blame] | 784 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 785 | int search_center = (int)((TRAIN_POS + GUARD_PERIOD) * d_OSR); |
piotr | 7c82b17 | 2014-02-08 14:15:27 +0100 | [diff] [blame] | 786 | int search_start_pos = search_center + 1 - 5*d_OSR; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 787 | // int search_start_pos = search_center - d_chan_imp_length * d_OSR; |
piotr | 5c82025 | 2014-04-17 09:43:02 +0200 | [diff] [blame] | 788 | int search_stop_pos = search_center + d_chan_imp_length * d_OSR + 5 * d_OSR; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 789 | |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 790 | for(int ii = search_start_pos; ii < search_stop_pos; ii++) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 791 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 792 | gr_complex correlation = correlate_sequence(&d_norm_training_seq[bcc][TRAIN_BEGINNING], N_TRAIN_BITS - 10, &input[ii]); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 793 | correlation_buffer.push_back(correlation); |
| 794 | power_buffer.push_back(std::pow(abs(correlation), 2)); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 795 | } |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 796 | // plot(power_buffer); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 797 | //compute window energies |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 798 | std::vector<float>::iterator iter = power_buffer.begin(); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 799 | bool loop_end = false; |
| 800 | while (iter != power_buffer.end()) |
| 801 | { |
ptrkrysik | ef5e2db | 2015-01-03 12:10:14 +0100 | [diff] [blame] | 802 | std::vector<float>::iterator iter_ii = iter; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 803 | energy = 0; |
| 804 | |
Piotr Krysik | 97d4f8a | 2016-02-11 08:40:44 +0100 | [diff] [blame] | 805 | for (int ii = 0; ii < (d_chan_imp_length)*d_OSR; ii++, iter_ii++) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 806 | { |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 807 | if (iter_ii == power_buffer.end()) |
| 808 | { |
| 809 | loop_end = true; |
| 810 | break; |
| 811 | } |
| 812 | energy += (*iter_ii); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 813 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 814 | if (loop_end) |
| 815 | { |
| 816 | break; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 817 | } |
| 818 | iter++; |
| 819 | |
| 820 | window_energy_buffer.push_back(energy); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 821 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 822 | |
piotr | 5c82025 | 2014-04-17 09:43:02 +0200 | [diff] [blame] | 823 | strongest_window_nr = max_element(window_energy_buffer.begin(), window_energy_buffer.end()-((d_chan_imp_length)*d_OSR)) - window_energy_buffer.begin(); |
| 824 | //strongest_window_nr = strongest_window_nr-d_OSR; |
| 825 | if(strongest_window_nr<0){ |
| 826 | strongest_window_nr = 0; |
| 827 | } |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 828 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 829 | max_correlation = 0; |
| 830 | for (int ii = 0; ii < (d_chan_imp_length)*d_OSR; ii++) |
| 831 | { |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 832 | gr_complex correlation = correlation_buffer[strongest_window_nr + ii]; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 833 | if (abs(correlation) > max_correlation) |
| 834 | { |
| 835 | chan_imp_resp_center = ii; |
| 836 | max_correlation = abs(correlation); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 837 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 838 | // d_channel_imp_resp.push_back(correlation); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 839 | chan_imp_resp[ii] = correlation; |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 840 | } |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 841 | |
piotr | 7e3b0db | 2014-02-05 22:44:30 +0100 | [diff] [blame] | 842 | *corr_max = max_correlation; |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 843 | |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 844 | //DCOUT("strongest_window_nr_new: " << strongest_window_nr); |
piotr | c7c249a | 2014-05-02 17:24:08 +0200 | [diff] [blame] | 845 | burst_start = search_start_pos + strongest_window_nr - TRAIN_POS * d_OSR; //compute first sample posiiton which corresponds to the first sample of the impulse response |
piotr | 7c82b17 | 2014-02-08 14:15:27 +0100 | [diff] [blame] | 846 | |
ptrkrysik | 5821379 | 2014-10-30 09:05:15 +0100 | [diff] [blame] | 847 | //DCOUT("burst_start: " << burst_start); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 848 | return burst_start; |
| 849 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 850 | |
| 851 | |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 852 | void receiver_impl::send_burst(burst_counter burst_nr, const unsigned char * burst_binary, uint8_t burst_type, unsigned int input_nr) |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 853 | { |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 854 | boost::scoped_ptr<gsmtap_hdr> tap_header(new gsmtap_hdr()); |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 855 | |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 856 | tap_header->version = GSMTAP_VERSION; |
ptrkrysik | 7f61c64 | 2014-10-30 08:57:27 +0100 | [diff] [blame] | 857 | tap_header->hdr_len = sizeof(gsmtap_hdr)/4; |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 858 | tap_header->type = GSMTAP_TYPE_UM_BURST; |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 859 | tap_header->sub_type = burst_type; |
ptrkrysik | 380dea8 | 2015-08-06 10:11:58 +0200 | [diff] [blame] | 860 | bool uplink_burst = (input_nr >= d_cell_allocation.size()); |
| 861 | if(!uplink_burst) // downlink burst |
| 862 | { |
| 863 | tap_header->timeslot = static_cast<uint8_t>(d_burst_nr.get_timeslot_nr()); |
| 864 | tap_header->frame_number = htobe32(d_burst_nr.get_frame_nr()); |
| 865 | tap_header->arfcn = htobe16(d_cell_allocation[input_nr]) ; |
| 866 | } |
| 867 | else //uplink burst |
| 868 | { |
| 869 | tap_header->timeslot = static_cast<uint8_t>(d_burst_nr.subtract_timeslots(3).get_timeslot_nr()); |
| 870 | tap_header->frame_number = htobe32(d_burst_nr.subtract_timeslots(3).get_frame_nr()); |
| 871 | input_nr = input_nr - d_cell_allocation.size(); |
| 872 | tap_header->arfcn = htobe16(d_cell_allocation[input_nr] | 0x4000); |
| 873 | } |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 874 | tap_header->signal_dbm = static_cast<int8_t>(d_signal_dbm); |
ptrkrysik | 6f6d46d | 2014-11-12 22:50:18 +0100 | [diff] [blame] | 875 | tap_header->snr_db = 0; |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 876 | |
| 877 | int8_t header_plus_burst[sizeof(gsmtap_hdr)+BURST_SIZE]; |
| 878 | memcpy(header_plus_burst, tap_header.get(), sizeof(gsmtap_hdr)); |
| 879 | memcpy(header_plus_burst+sizeof(gsmtap_hdr), burst_binary, BURST_SIZE); |
| 880 | |
| 881 | pmt::pmt_t blob_header_plus_burst = pmt::make_blob(header_plus_burst,sizeof(gsmtap_hdr)+BURST_SIZE); |
| 882 | pmt::pmt_t msg = pmt::cons(pmt::PMT_NIL, blob_header_plus_burst); |
piotr | f2b6a1b | 2014-08-04 11:28:59 +0200 | [diff] [blame] | 883 | |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 884 | if(input_nr==0){ |
| 885 | message_port_pub(pmt::mp("C0"), msg); |
| 886 | } else { |
| 887 | message_port_pub(pmt::mp("CX"), msg); |
| 888 | } |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 889 | } |
piotr | 6d152d9 | 2014-02-21 00:02:44 +0100 | [diff] [blame] | 890 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 891 | void receiver_impl::configure_receiver() |
| 892 | { |
piotr | ce92f98 | 2014-04-17 23:37:18 +0200 | [diff] [blame] | 893 | d_channel_conf.set_multiframe_type(TIMESLOT0, multiframe_51); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 894 | d_channel_conf.set_burst_types(TIMESLOT0, TEST51, sizeof(TEST51) / sizeof(unsigned), dummy_or_normal); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 895 | |
piotr | ce92f98 | 2014-04-17 23:37:18 +0200 | [diff] [blame] | 896 | d_channel_conf.set_burst_types(TIMESLOT0, TEST_CCH_FRAMES, sizeof(TEST_CCH_FRAMES) / sizeof(unsigned), dummy_or_normal); |
| 897 | d_channel_conf.set_burst_types(TIMESLOT0, FCCH_FRAMES, sizeof(FCCH_FRAMES) / sizeof(unsigned), fcch_burst); |
| 898 | d_channel_conf.set_burst_types(TIMESLOT0, SCH_FRAMES, sizeof(SCH_FRAMES) / sizeof(unsigned), sch_burst); |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 899 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 900 | d_channel_conf.set_multiframe_type(TIMESLOT1, multiframe_51); |
| 901 | d_channel_conf.set_burst_types(TIMESLOT1, TEST51, sizeof(TEST51) / sizeof(unsigned), dummy_or_normal); |
| 902 | d_channel_conf.set_multiframe_type(TIMESLOT2, multiframe_51); |
| 903 | d_channel_conf.set_burst_types(TIMESLOT2, TEST51, sizeof(TEST51) / sizeof(unsigned), dummy_or_normal); |
| 904 | d_channel_conf.set_multiframe_type(TIMESLOT3, multiframe_51); |
| 905 | d_channel_conf.set_burst_types(TIMESLOT3, TEST51, sizeof(TEST51) / sizeof(unsigned), dummy_or_normal); |
| 906 | d_channel_conf.set_multiframe_type(TIMESLOT4, multiframe_51); |
| 907 | d_channel_conf.set_burst_types(TIMESLOT4, TEST51, sizeof(TEST51) / sizeof(unsigned), dummy_or_normal); |
| 908 | d_channel_conf.set_multiframe_type(TIMESLOT5, multiframe_51); |
| 909 | d_channel_conf.set_burst_types(TIMESLOT5, TEST51, sizeof(TEST51) / sizeof(unsigned), dummy_or_normal); |
| 910 | d_channel_conf.set_multiframe_type(TIMESLOT6, multiframe_51); |
| 911 | d_channel_conf.set_burst_types(TIMESLOT6, TEST51, sizeof(TEST51) / sizeof(unsigned), dummy_or_normal); |
| 912 | d_channel_conf.set_multiframe_type(TIMESLOT7, multiframe_51); |
| 913 | d_channel_conf.set_burst_types(TIMESLOT7, TEST51, sizeof(TEST51) / sizeof(unsigned), dummy_or_normal); |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 914 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 915 | |
ptrkrysik | 7a7b9b0 | 2014-11-19 11:27:34 +0100 | [diff] [blame] | 916 | void receiver_impl::set_cell_allocation(const std::vector<int> &cell_allocation) |
piotr | f2b6a1b | 2014-08-04 11:28:59 +0200 | [diff] [blame] | 917 | { |
ptrkrysik | e518bbf | 2014-11-06 14:50:59 +0100 | [diff] [blame] | 918 | d_cell_allocation = cell_allocation; |
| 919 | } |
| 920 | |
| 921 | void receiver_impl::set_tseq_nums(const std::vector<int> & tseq_nums) |
| 922 | { |
| 923 | d_tseq_nums = tseq_nums; |
piotr | f2b6a1b | 2014-08-04 11:28:59 +0200 | [diff] [blame] | 924 | } |
| 925 | |
| 926 | void receiver_impl::reset() |
| 927 | { |
piotr | d6d6687 | 2014-08-06 15:20:33 +0200 | [diff] [blame] | 928 | d_state = fcch_search; |
piotr | f2b6a1b | 2014-08-04 11:28:59 +0200 | [diff] [blame] | 929 | } |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 930 | |
piotr | d0bf149 | 2014-02-05 17:27:32 +0100 | [diff] [blame] | 931 | } /* namespace gsm */ |
piotr | 437f546 | 2014-02-04 17:57:25 +0100 | [diff] [blame] | 932 | } /* namespace gr */ |
| 933 | |