diff options
Diffstat (limited to 'src/lib/gsm_receiver_cf.cc')
| -rw-r--r-- | src/lib/gsm_receiver_cf.cc | 163 |
1 files changed, 142 insertions, 21 deletions
diff --git a/src/lib/gsm_receiver_cf.cc b/src/lib/gsm_receiver_cf.cc index f94e303..4742b33 100644 --- a/src/lib/gsm_receiver_cf.cc +++ b/src/lib/gsm_receiver_cf.cc @@ -33,21 +33,102 @@ #include <numeric> #include <gsm_receiver_cf.h> #include <viterbi_detector.h> +#include <string.h> #include <sch.h> + +#include "RxBurst.h" +#include "GSMCommon.h" + #define SYNC_SEARCH_RANGE 30 -#define TRAIN_SEARCH_RANGE 40 +// #define TRAIN_SEARCH_RANGE 40 +//FIXME: decide to use this define or not //TODO: this shouldn't be here - remove it when gsm receiver's interface will be ready +void decrypt(const unsigned char * burst_binary, byte * KC, float * decrypted_data, unsigned FN) +{ + byte AtoB[2*DATA_BITS]; + + keysetup(KC, FN); + runA51(AtoB); + + for (int i = 0; i < 148; i++) { + decrypted_data[i] = burst_binary[i]; + } + + for (int i = 0; i < 57; i++) { + decrypted_data[i+3] = AtoB[i] ^ burst_binary[i+3]; + } + + for (int i = 0; i < 57; i++) { + decrypted_data[i+88] = AtoB[i+57] ^ burst_binary[i+88]; + } +} + +void gsm_receiver_cf::read_key(std::string key) +{ + int i; + int b; + for (i = 0;i < 8;i++) { + b = d_hex_to_int[(char)key[(i)*2]]*16 + d_hex_to_int[(char)key[i*2+1]]; + d_KC[i] = (byte)b; + } +} + void gsm_receiver_cf::process_normal_burst(burst_counter burst_nr, const unsigned char * burst_binary) { - if (burst_nr.get_timeslot_nr() == 0) { -// printf(" %2d %6x %6x", burst_nr.get_t2(), burst_nr.get_frame_nr(), burst_nr.get_frame_nr_mod()); -// for (int i = 0; i < BURST_SIZE ; i++) { -// printf(" %d", burst_binary[i]); -// } -// std::cout << "\n"; -// std::cout << " bcc: " << d_bcc << "\n"; +// static byte KC[] = { 0xAD, 0x6A, 0x3E, 0xC2, 0xB4, 0x42, 0xE4, 0x00 }; +// static byte KC[] = { 0x2B, 0x08, 0x74, 0x9F, 0xDD, 0x0D, 0x9C, 0x00 }; +// printf("%x", KC[0]); + float decrypted_data[148]; + unsigned char * voice_frame; + +// if (burst_nr.get_timeslot_nr() == 7) { + if (burst_nr.get_timeslot_nr() >= 1 && burst_nr.get_timeslot_nr() <= 7) { + decrypt(burst_binary, d_KC, decrypted_data, burst_nr.get_frame_nr_mod()); + + GSM::Time time(burst_nr.get_frame_nr(), burst_nr.get_timeslot_nr()); + GSM::RxBurst rxbrst(decrypted_data, time); + switch (burst_nr.get_timeslot_nr()) { + case 1: + if ( d_tch_decoder1.processBurst( rxbrst ) == true) { + fwrite(d_tch_decoder1.get_voice_frame(), 1 , 33, d_gsm_file); + } + break; + case 2: + if ( d_tch_decoder2.processBurst( rxbrst ) == true) { + fwrite(d_tch_decoder2.get_voice_frame(), 1 , 33, d_gsm_file); + } + break; + case 3: + if ( d_tch_decoder3.processBurst( rxbrst ) == true) { + fwrite(d_tch_decoder3.get_voice_frame(), 1 , 33, d_gsm_file); + } + break; + case 4: + if ( d_tch_decoder4.processBurst( rxbrst ) == true) { + fwrite(d_tch_decoder4.get_voice_frame(), 1 , 33, d_gsm_file); + } + break; + case 5: + if ( d_tch_decoder5.processBurst( rxbrst ) == true) { + fwrite(d_tch_decoder5.get_voice_frame(), 1 , 33, d_gsm_file); + } + break; + case 6: + if ( d_tch_decoder6.processBurst( rxbrst ) == true) { + fwrite(d_tch_decoder6.get_voice_frame(), 1 , 33, d_gsm_file); + } + break; + case 7: + if ( d_tch_decoder7.processBurst( rxbrst ) == true) { + fwrite(d_tch_decoder7.get_voice_frame(), 1 , 33, d_gsm_file); + } + break; + } + } + + if (burst_nr.get_timeslot_nr() == 0) { GS_process(&d_gs_ctx, TIMESLOT0, 6, &burst_binary[3], burst_nr.get_frame_nr()); } } @@ -59,8 +140,24 @@ void gsm_receiver_cf::configure_receiver() d_channel_conf.set_burst_types(TSC0, TEST_CCH_FRAMES, sizeof(TEST_CCH_FRAMES) / sizeof(unsigned), normal_burst); d_channel_conf.set_burst_types(TSC0, FCCH_FRAMES, sizeof(FCCH_FRAMES) / sizeof(unsigned), fcch_burst); + d_channel_conf.set_multiframe_type(TIMESLOT1, multiframe_26); + d_channel_conf.set_burst_types(TIMESLOT1, TRAFFIC_CHANNEL_F, sizeof(TRAFFIC_CHANNEL_F) / sizeof(unsigned), dummy_or_normal); + d_channel_conf.set_multiframe_type(TIMESLOT2, multiframe_26); + d_channel_conf.set_burst_types(TIMESLOT2, TRAFFIC_CHANNEL_F, sizeof(TRAFFIC_CHANNEL_F) / sizeof(unsigned), dummy_or_normal); + + d_channel_conf.set_multiframe_type(TIMESLOT3, multiframe_26); + d_channel_conf.set_burst_types(TIMESLOT3, TRAFFIC_CHANNEL_F, sizeof(TRAFFIC_CHANNEL_F) / sizeof(unsigned), dummy_or_normal); + d_channel_conf.set_multiframe_type(TIMESLOT4, multiframe_26); + d_channel_conf.set_burst_types(TIMESLOT4, TRAFFIC_CHANNEL_F, sizeof(TRAFFIC_CHANNEL_F) / sizeof(unsigned), dummy_or_normal); + + d_channel_conf.set_multiframe_type(TIMESLOT5, multiframe_26); + d_channel_conf.set_burst_types(TIMESLOT5, TRAFFIC_CHANNEL_F, sizeof(TRAFFIC_CHANNEL_F) / sizeof(unsigned), dummy_or_normal); + d_channel_conf.set_multiframe_type(TIMESLOT6, multiframe_26); + d_channel_conf.set_burst_types(TIMESLOT6, TRAFFIC_CHANNEL_F, sizeof(TRAFFIC_CHANNEL_F) / sizeof(unsigned), dummy_or_normal); + d_channel_conf.set_multiframe_type(TIMESLOT7, multiframe_26); d_channel_conf.set_burst_types(TIMESLOT7, TRAFFIC_CHANNEL_F, sizeof(TRAFFIC_CHANNEL_F) / sizeof(unsigned), dummy_or_normal); + } @@ -70,9 +167,9 @@ typedef std::vector<float> vector_float; typedef boost::circular_buffer<float> circular_buffer_float; gsm_receiver_cf_sptr -gsm_make_receiver_cf(gr_feval_dd *tuner, gr_feval_dd *synchronizer, int osr) +gsm_make_receiver_cf(gr_feval_dd *tuner, gr_feval_dd *synchronizer, int osr, std::string key) { - return gsm_receiver_cf_sptr(new gsm_receiver_cf(tuner, synchronizer, osr)); + return gsm_receiver_cf_sptr(new gsm_receiver_cf(tuner, synchronizer, osr, key)); } static const int MIN_IN = 1; // mininum number of input streams @@ -83,7 +180,7 @@ static const int MAX_OUT = 1; // maximum number of output streams /* * The private constructor */ -gsm_receiver_cf::gsm_receiver_cf(gr_feval_dd *tuner, gr_feval_dd *synchronizer, int osr) +gsm_receiver_cf::gsm_receiver_cf(gr_feval_dd *tuner, gr_feval_dd *synchronizer, int osr, std::string key) : gr_block("gsm_receiver", gr_make_io_signature(MIN_IN, MAX_IN, sizeof(gr_complex)), gr_make_io_signature(MIN_OUT, MAX_OUT, 142 * sizeof(float))), @@ -95,15 +192,21 @@ gsm_receiver_cf::gsm_receiver_cf(gr_feval_dd *tuner, gr_feval_dd *synchronizer, d_freq_offset(0), d_state(first_fcch_search), d_burst_nr(osr), - d_failed_sch(0) + d_failed_sch(0), + d_tch_decoder1( GSM::gFACCH_TCHFMapping ), + d_tch_decoder2( GSM::gFACCH_TCHFMapping ), + d_tch_decoder3( GSM::gFACCH_TCHFMapping ), + d_tch_decoder4( GSM::gFACCH_TCHFMapping ), + d_tch_decoder5( GSM::gFACCH_TCHFMapping ), + d_tch_decoder6( GSM::gFACCH_TCHFMapping ), + d_tch_decoder7( GSM::gFACCH_TCHFMapping ) { int i; gmsk_mapper(SYNC_BITS, N_SYNC_BITS, d_sch_training_seq, gr_complex(0.0, -1.0)); - for (i = 0; i < TRAIN_SEQ_NUM; i++) { gr_complex startpoint; if (i == 6) { //this is nasty hack - startpoint = gr_complex(-1.0, 0.0); //if I don't change it here all bits of normal bursts for BTSes with bcc=6 will have negative values + startpoint = gr_complex(-1.0, 0.0); //if I don't change it here all bits of normal bursts for BTSes with bcc=6 will have reversed values } else { startpoint = gr_complex(1.0, 0.0); //I've checked this hack for bcc==0,1,2,3,4,6 } //I don't know what about bcc==5 and 7 yet @@ -111,7 +214,25 @@ gsm_receiver_cf::gsm_receiver_cf(gr_feval_dd *tuner, gr_feval_dd *synchronizer, gmsk_mapper(train_seq[i], N_TRAIN_BITS, d_norm_training_seq[i], startpoint); } - + d_gsm_file = fopen( "speech.gsm", "wb" ); + + d_hex_to_int['0'] = 0; + d_hex_to_int['4'] = 4; + d_hex_to_int['8'] = 8; + d_hex_to_int['c'] = 0xc; + d_hex_to_int['1'] = 1; + d_hex_to_int['5'] = 5; + d_hex_to_int['9'] = 9; + d_hex_to_int['d'] = 0xd; + d_hex_to_int['2'] = 2; + d_hex_to_int['6'] = 6; + d_hex_to_int['a'] = 0xa; + d_hex_to_int['e'] = 0xe; + d_hex_to_int['3'] = 3; + d_hex_to_int['7'] = 7; + d_hex_to_int['b'] = 0xb; + d_hex_to_int['f'] = 0xf; + read_key(key); /* Initialize GSM Stack */ GS_new(&d_gs_ctx); //TODO: remove it! it's not a right place for a decoder } @@ -153,7 +274,7 @@ gsm_receiver_cf::general_work(int noutput_items, break; case next_fcch_search: { //this state is used because it takes some time (a bunch of buffered samples) - float prev_freq_offset = d_freq_offset; //before previous set_frequqency cause change + float prev_freq_offset = d_freq_offset; //before previous set_frequqency cause change if (find_fcch_burst(input, nitems_items[0])) { if (abs(prev_freq_offset - d_freq_offset) > FCCH_MAX_FREQ_OFFSET) { set_frequency(d_freq_offset); //call set_frequncy only frequency offset change is greater than some value @@ -253,13 +374,13 @@ gsm_receiver_cf::general_work(int noutput_items, break; case normal_burst: //if it's normal burst - burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], TRAIN_SEARCH_RANGE, d_bcc); //get channel impulse response for given training sequence number - d_bcc + burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], d_bcc); //get channel impulse response for given training sequence number - d_bcc detect_burst(input, &channel_imp_resp[0], burst_start, output_binary); //MLSE detection of bits process_normal_burst(d_burst_nr, output_binary); //TODO: this shouldn't be here - remove it when gsm receiver's interface will be ready break; case dummy_or_normal: { - burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], TRAIN_SEARCH_RANGE, TS_DUMMY); + burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], TS_DUMMY); detect_burst(input, &channel_imp_resp[0], burst_start, output_binary); std::vector<unsigned char> v(20); @@ -268,7 +389,7 @@ gsm_receiver_cf::general_work(int noutput_items, int different_bits = (it - v.begin()); if (different_bits > 2) { - burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], TRAIN_SEARCH_RANGE, d_bcc); + burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], d_bcc); detect_burst(input, &channel_imp_resp[0], burst_start, output_binary); if (!output_binary[0] && !output_binary[1] && !output_binary[2]) { process_normal_burst(d_burst_nr, output_binary); //TODO: this shouldn't be here - remove it when gsm receiver's interface will be ready @@ -283,7 +404,7 @@ gsm_receiver_cf::general_work(int noutput_items, break; case dummy: //if it's dummy - burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], TRAIN_SEARCH_RANGE, TS_DUMMY); //read dummy + burst_start = get_norm_chan_imp_resp(input, &channel_imp_resp[0], TS_DUMMY); //read dummy detect_burst(input, &channel_imp_resp[0], burst_start, output_binary); // but as far as I know it's pointless break; case empty: //if it's empty burst @@ -652,7 +773,7 @@ inline void gsm_receiver_cf::mafi(const gr_complex * input, int nitems, gr_compl //TODO: get_norm_chan_imp_resp is similar to get_sch_chan_imp_resp - consider joining this two functions //TODO: this is place where most errors are introduced and can be corrected by improvements to this fuction //especially computations of strongest_window_nr -int gsm_receiver_cf::get_norm_chan_imp_resp(const gr_complex *input, gr_complex * chan_imp_resp, unsigned search_range, int bcc) +int gsm_receiver_cf::get_norm_chan_imp_resp(const gr_complex *input, gr_complex * chan_imp_resp, int bcc) { vector_complex correlation_buffer; vector_float power_buffer; |