diff --git a/openair1/SIMULATION/NR_PHY/dlsim.c b/openair1/SIMULATION/NR_PHY/dlsim.c
index be2c966f95db676bc38a90f2e423925411708431..73a540747a122a4f07dd7db9b72dc661aa7c70da 100644
--- a/openair1/SIMULATION/NR_PHY/dlsim.c
+++ b/openair1/SIMULATION/NR_PHY/dlsim.c
@@ -77,6 +77,7 @@ int32_t uplink_frequency_offset[MAX_NUM_CCs][4];
 double cpuf;
 
 int sf_ahead=4 ;
+int sl_ahead=0;
 uint8_t nfapi_mode = 0;
 uint16_t NB_UE_INST = 1;
 
diff --git a/openair1/SIMULATION/NR_PHY/ulsim.c b/openair1/SIMULATION/NR_PHY/ulsim.c
index cab19f50b41f2f1a2f9385d3eb4b4bc80b25b07a..5816befd934ff28399328ef4d400e2d14661440c 100644
--- a/openair1/SIMULATION/NR_PHY/ulsim.c
+++ b/openair1/SIMULATION/NR_PHY/ulsim.c
@@ -63,6 +63,7 @@ RAN_CONTEXT_t RC;
 int32_t uplink_frequency_offset[MAX_NUM_CCs][4];
 
 int sf_ahead=4 ;
+int sl_ahead=0;
 double cpuf;
 uint8_t nfapi_mode = 0;
 uint16_t NB_UE_INST = 1;