From 7c941435ad6fccde51cb219ae12a09729e8d6369 Mon Sep 17 00:00:00 2001
From: Guido Casati <guido.casati@iis.fraunhofer.de>
Date: Mon, 15 Nov 2021 16:06:28 +0100
Subject: [PATCH] Bugfix wrong configuration of initial ack nack timing in FDD
 mode

---
 openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
index ef3ac0d5f5..d202145864 100644
--- a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
+++ b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
@@ -1310,8 +1310,9 @@ int nr_acknack_scheduling(int mod_id,
     AssertFatal(pucch->sr_flag + pucch->dai_c == 0,
                 "expected no SR/AckNack for UE %d in %4d.%2d, but has %d/%d for %4d.%2d\n",
                 UE_id, frame, slot, pucch->sr_flag, pucch->dai_c, pucch->frame, pucch->ul_slot);
-    pucch->frame = frame;
-    pucch->ul_slot = tdd ? first_ul_slot_tdd : slot + minfbtime;
+    const int s = tdd ? first_ul_slot_tdd : slot + minfbtime;
+    pucch->frame = (s < n_slots_frame - 1) ? frame : (frame + 1) % 1024;
+    pucch->ul_slot = s % n_slots_frame;
   }
 
   // Find the right timing_indicator value.