fixeria has submitted this change. ( https://gerrit.osmocom.org/c/osmo-pcu/+/29880 ) Change subject: bts: bts_snd_dl_ass(): clarify the meaning of last_rts_fn + 21216 ...................................................................... bts: bts_snd_dl_ass(): clarify the meaning of last_rts_fn + 21216 Change-Id: I8127e17607426443bb95b42873b580fc9f400af9 --- M src/bts.cpp 1 file changed, 5 insertions(+), 2 deletions(-) Approvals: pespin: Looks good to me, approved Jenkins Builder: Verified diff --git a/src/bts.cpp b/src/bts.cpp index df08cc6..3eb41d2 100644 --- a/src/bts.cpp +++ b/src/bts.cpp @@ -1083,8 +1083,11 @@ LOGPTBF(tbf, LOGL_INFO, "TX: START Immediate Assignment Downlink (PCH)\n"); bitvec *immediate_assignment = bitvec_alloc(22, tall_pcu_ctx); /* without plen */ bitvec_unhex(immediate_assignment, DUMMY_VEC); /* standard '2B'O padding */ - /* use request reference that has maximum distance to current time, - * so the assignment will not conflict with possible RACH requests. */ + /* 3GPP TS 44.018, section 9.1.18.0d states that the network shall code the + * Request Reference IE, e.g. by using a suitably offset frame number, such + * that the resource reference cannot be confused with any CHANNEL REQUEST + * message sent by a mobile station. Use last_rts_fn + 21216 (16 TDMA + * super-frame periods, or ~21.3 seconds) to achieve a decent distance. */ LOGP(DRLCMAC, LOGL_DEBUG, " - TRX=%d (%d) TS=%d TA=%d\n", trx_no, tbf->trx->arfcn, ts_no, tbf->ta()); plen = Encoding::write_immediate_assignment(&bts->trx[trx_no].pdch[ts_no], -- To view, visit https://gerrit.osmocom.org/c/osmo-pcu/+/29880 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: osmo-pcu Gerrit-Branch: master Gerrit-Change-Id: I8127e17607426443bb95b42873b580fc9f400af9 Gerrit-Change-Number: 29880 Gerrit-PatchSet: 1 Gerrit-Owner: fixeria <vyanitskiy(a)sysmocom.de> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: fixeria <vyanitskiy(a)sysmocom.de> Gerrit-Reviewer: pespin <pespin(a)sysmocom.de> Gerrit-MessageType: merged