diff options
Diffstat (limited to 'gssm/src/lib/bursts.cc')
| -rw-r--r-- | gssm/src/lib/bursts.cc | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/gssm/src/lib/bursts.cc b/gssm/src/lib/bursts.cc new file mode 100644 index 0000000..cd35382 --- /dev/null +++ b/gssm/src/lib/bursts.cc @@ -0,0 +1,153 @@ +// $Id: bursts.cc,v 1.1.1.1 2007-06-01 04:26:57 jl Exp $ + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include "burst_types.h" + +void display_burst_type(burst_t t) { + + switch(t) { + case burst_n_0: + case burst_n_1: + case burst_n_2: + case burst_n_3: + case burst_n_4: + case burst_n_5: + case burst_n_6: + case burst_n_7: + printf("normal burst %d", t); + break; + case burst_fc: + printf("frequency correction burst"); + break; + case burst_fc_c: + printf("frequency correction burst (COMPACT)"); + break; + case burst_s: + printf("synchronization burst"); + break; + case burst_s_cts: + printf("synchronization burst (CTS)"); + break; + case burst_s_c: + printf("synchronization burst (COMPACT)"); + break; + case burst_d: + printf("dummy burst"); + break; + case burst_a: + printf("access burst"); + break; + case burst_a_ts1: + printf("access burst (TS1)"); + break; + case burst_a_ts2: + printf("access burst (TS2)"); + break; + default: + printf("unknown burst type"); + break; + } +} + + +static int burst_diff(const unsigned char *b1, const unsigned char *b2, + unsigned int l) { + + int d = 0; + unsigned int i; + + for(i = 0; i < l; i++) + d += (b1[i] ^ b2[i]); + return d; +} + + +int search_fc(unsigned char *buf) { + + return !(burst_diff(buf + TB_OS1, tail_bits, TB_LEN) + + burst_diff(buf + TB_OS2, tail_bits, TB_LEN) + + burst_diff(buf + FC_OS, fc_fb, FC_CODE_LEN)); +} + + +int is_dummy_burst(const unsigned char *buf) { + + int i; + + for(i = 0; i < D_CODE_LEN; i++) + if(buf[i + D_MB_OS] != d_mb[i]) + return 0; + return 1; +} + + +burst_t search_burst(unsigned char *buf, int max_burst_errors, int *rmin_o) { + + int i, d_burst[N_BURST_TYPES], t_d, d_min, rmin; + burst_t bt_min; + + for(i = 0; i < N_BURST_TYPES; i++) + d_burst[i] = max_burst_errors + 1; + + // access burst (uplink only) + t_d = burst_diff(buf + AB_ETB_OS, ab_etb, AB_ETB_CODE_LEN); + d_burst[(int)burst_a] = + t_d + burst_diff(buf + AB_SSB_OS, ab_ssb, AB_SSB_CODE_LEN); + + d_burst[(int)burst_a_ts1] = + t_d + burst_diff(buf + AB_SSB_OS, ab_ts1_ssb, AB_SSB_CODE_LEN); + + d_burst[(int)burst_a_ts2] = + t_d + burst_diff(buf + AB_SSB_OS, ab_ts2_ssb, AB_SSB_CODE_LEN); + + // check tail bits + t_d = + burst_diff(buf + TB_OS1, tail_bits, TB_LEN) + + burst_diff(buf + TB_OS2, tail_bits, TB_LEN); + + // normal bursts + for(i = 0; i < N_TSC_NUM; i++) + d_burst[(int)burst_n_0 + i] = + t_d + burst_diff(buf + N_TSC_OS, n_tsc[i], N_TSC_CODE_LEN); + + // frequency correction + d_burst[(int)burst_fc] = + t_d + burst_diff(buf + FC_OS, fc_fb, FC_CODE_LEN); + + d_burst[(int)burst_fc_c] = + t_d + burst_diff(buf + FC_OS, fc_compact_fb, FC_CODE_LEN); + + // synchronization burst + d_burst[(int)burst_s] = + t_d + burst_diff(buf + SB_ETS_OS, sb_etsc, SB_CODE_LEN); + + d_burst[(int)burst_s_cts] = + t_d + burst_diff(buf + SB_ETS_OS, sb_cts_etsc, SB_CODE_LEN); + + d_burst[(int)burst_s_c] = + t_d + burst_diff(buf + SB_ETS_OS, sb_compact_etsc, SB_CODE_LEN); + + // dummy + d_burst[(int)burst_d] = + t_d + burst_diff(buf + D_MB_OS, d_mb, D_CODE_LEN); + + d_burst[(int)burst_not_a_burst] = max_burst_errors; + + rmin = BURST_LENGTH; + d_min = max_burst_errors + 1; + bt_min = burst_not_a_burst; + for(i = 0; i < N_BURST_TYPES; i++) { + if(d_burst[i] < d_min) { + bt_min = (burst_t)i; + d_min = d_burst[i]; + } + if((d_burst[i] < rmin) && ((burst_t)i != burst_not_a_burst)) + rmin = d_burst[i]; + } + if(rmin_o) + *rmin_o = rmin; + return bt_min; +} |