diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/osmo-bts-trx/scheduler_trx.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/src/osmo-bts-trx/scheduler_trx.c b/src/osmo-bts-trx/scheduler_trx.c index 7bdbc4f9..00d7bbb5 100644 --- a/src/osmo-bts-trx/scheduler_trx.c +++ b/src/osmo-bts-trx/scheduler_trx.c @@ -784,19 +784,22 @@ int rx_rach_fn(struct l1sched_trx *l1t, enum trx_chan_type chan, uint8_t ra; int rc; - /* It would be great if the transceiver were doing some kind of tagging, - * whether it is extended (11-bit) RACH or not. We would not need to guess - * it here. For now, let's try to correlate the synch. sequence of a received - * Access Burst with the known ones (3GPP TS 05.02, section 5.2.7), and - * fall-back to the default TS0 if it fails. This would save some CPU - * power, and what is more important - prevent possible collisions. */ + /* TSC (Training Sequence Code) is an optional parameter of the UL burst + * indication. We need this information in order to decide whether an + * Access Burst is 11-bit encoded or not (see OS#1854). If this information + * is absent, we try to correlate the received synch. sequence with the + * known ones (3GPP TS 05.02, section 5.2.7), and fall-back to the default + * TS0 if it fails. */ enum rach_synch_seq_t synch_seq = RACH_SYNCH_SEQ_TS0; int best_score = 127 * RACH_SYNCH_SEQ_LEN; /* Handover RACH cannot be extended (11-bit) */ - if (chan == TRXC_RACH) - /* TODO: check for TRX_BI_F_TS_INFO flag! */ - synch_seq = rach_get_synch_seq((sbit_t *) bi->burst, &best_score); + if (chan == TRXC_RACH) { + if (bi->flags & TRX_BI_F_TS_INFO) + synch_seq = (enum rach_synch_seq_t) bi->tsc; + else + synch_seq = rach_get_synch_seq((sbit_t *) bi->burst, &best_score); + } LOGL1S(DL1P, LOGL_DEBUG, l1t, bi->tn, chan, bi->fn, "Received RACH (%s; match=%.1f%%) toa=%d\n", |