maki/openairinterface5g
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Merge remote-tracking branch 'origin/issue-954-fix' into integration_2025_w38 (!3568)

Browse Source 
Fix UE DCI monitoring after RRC setup

After the UE is configured with pdcch-Config, it continues to monitor
fallback search spaces in pdcch-ConfigCommon for DCI with C-RNTI.

The rational is that after sending RRC Setup the network won't know if
the UE has received and successfully applied it. Hence the network would
still continue to use the fallback DCI till it receives RRC setup
complete.

Closes #954
This commit is contained in:
Jaroslava Fiedlerova
2025-09-17 10:14:57 +02:00
parent a9a554508d 524aa84e96
commit 44fa1c2244
1 changed files with 32 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files
openair2/LAYER2/NR_MAC_UE/nr_ue_dci_configuration.c
+32 -9
View File
@@ -489,19 +489,42 @@ void ue_dci_configuration(NR_UE_MAC_INST_t *mac, fapi_nr_dl_config_request_t *dl
config_dci_pdu(mac, dl_config, rnti_type, slot, ra_SS);
}
} else if (mac->state == UE_CONNECTED) {
/*
In RRC Connected state, the UE monitors for fallback DCI with C-RNTI in common and UE-specific SS.
First the UE check all UE specific SS. If no fallback DCI is configured, it configures one of following
common SS with the shown priority
1. RA SS
2. Other SI SS
3. Paging SS
4. SIB1 SS
There is a possibility that gNB could configure multiple UE-specific SS for fallback DCI or/and common SS,
and in a given slot more than one SS become active. For the moment, we assume such configuration wouldn't happen
and hence don't handle it for the sake of implementation simplicity.
*/
bool configured_fallback_dci = false;
for (int i = 0; i < pdcch_config->list_SS.count; i++) {
NR_SearchSpace_t *ss = pdcch_config->list_SS.array[i];
if (is_ss_monitor_occasion(frame, slot, slots_per_frame, ss))
if (is_ss_monitor_occasion(frame, slot, slots_per_frame, ss)) {
config_dci_pdu(mac, dl_config, TYPE_C_RNTI_, slot, ss);
configured_fallback_dci |= (ss->searchSpaceType->present == NR_SearchSpace__searchSpaceType_PR_common);
}
}
const NR_SearchSpace_t *ra_SS = get_common_search_space(mac, pdcch_config->ra_SS_id);
if (pdcch_config->list_SS.count == 0 && ra_SS) {
// If the UE has not been provided a Type3-PDCCH CSS set or a USS set and
// the UE has received a C-RNTI and has been provided a Type1-PDCCH CSS set,
// the UE monitors PDCCH candidates for DCI format 0_0 and DCI format 1_0
// with CRC scrambled by the C-RNTI in the Type1-PDCCH CSS set
if (is_ss_monitor_occasion(frame, slot, slots_per_frame, ra_SS))
config_dci_pdu(mac, dl_config, TYPE_C_RNTI_, slot, ra_SS);
const NR_SearchSpace_t *css = NULL;
if (!configured_fallback_dci) {
#define CSS_VALID_CUR_SLOT(CSS) \
((CSS > -1) && is_ss_monitor_occasion(frame, slot, slots_per_frame, get_common_search_space(mac, CSS)))
if (CSS_VALID_CUR_SLOT(pdcch_config->ra_SS_id))
css = get_common_search_space(mac, pdcch_config->ra_SS_id);
else if (CSS_VALID_CUR_SLOT(pdcch_config->otherSI_SS_id))
css = get_common_search_space(mac, pdcch_config->otherSI_SS_id);
else if (CSS_VALID_CUR_SLOT(pdcch_config->paging_SS_id))
css = get_common_search_space(mac, pdcch_config->paging_SS_id);
#undef CSS_VALID_CUR_SLOT
else
css = mac->search_space_zero;
AssertFatal(css, "Atleast one CSS should be present in connected state\n");
config_dci_pdu(mac, dl_config, TYPE_C_RNTI_, slot, css);
}
}
}