diff --git a/openair2/LAYER2/NR_MAC_UE/mac_defs.h b/openair2/LAYER2/NR_MAC_UE/mac_defs.h
index ddb522dfb5..95df46fb72 100644
--- a/openair2/LAYER2/NR_MAC_UE/mac_defs.h
+++ b/openair2/LAYER2/NR_MAC_UE/mac_defs.h
@@ -283,8 +283,6 @@ typedef struct {
   int ra_preamble_rx_target_power;
   /// RA Preamble Power Ramping Step in dB
   uint32_t preamble_power_ramping_step;
-  uint8_t preamble_backoff;
-  uint8_t scaling_factor_bi;
   /// UE configured maximum output power
   int Pc_max;
 } NR_PRACH_RESOURCES_t;
@@ -310,8 +308,6 @@ typedef struct {
   bool cfra;
   /// RA type
   nr_ra_type_t ra_type;
-  /// RA rx frame offset: compensate RA rx offset introduced by OAI gNB.
-  uint8_t RA_offset;
   /// MsgB SuccessRAR MAC subheader
   int8_t MsgB_R;
   int8_t MsgB_CH_ACESS_CPEXT;
@@ -333,18 +329,15 @@ typedef struct {
   int restricted_set_config;
   // selected SSB for RACH (not the SSB-Index but the cumulative index, excluding not trasmitted SSBs)
   int ra_ssb;
-  /// Random-access window counter
-  int16_t RA_window_cnt;
-  /// Flag to monitor if matching RAPID was received in RAR
-  uint8_t RA_RAPID_found;
-  /// Flag to monitor if BI was received in RAR
-  uint8_t RA_BI_found;
-  /// Random-access backoff counter
-  int16_t RA_backoff_indicator;
+  /// Random-access response window timer
+  NR_timer_t response_window_timer;
+  bool start_response_window;
+  /// Random-access backoff timer
+  NR_timer_t RA_backoff_timer;
+  int RA_backoff_limit;
+  uint8_t scaling_factor_bi;
   /// Flag to indicate whether preambles Group A is selected
   bool RA_GroupA;
-  /// RA backoff counter
-  int16_t RA_backoff_cnt;
   /// RA max number of preamble transmissions
   int preambleTransMax;
   /// Received TPC command (in dB) from RAR
diff --git a/openair2/LAYER2/NR_MAC_UE/mac_proto.h b/openair2/LAYER2/NR_MAC_UE/mac_proto.h
index 6d2c7a1efd..2157a6c1c8 100644
--- a/openair2/LAYER2/NR_MAC_UE/mac_proto.h
+++ b/openair2/LAYER2/NR_MAC_UE/mac_proto.h
@@ -212,7 +212,6 @@ void set_harq_status(NR_UE_MAC_INST_t *mac,
 bool get_downlink_ack(NR_UE_MAC_INST_t *mac, frame_t frame, int slot, PUCCH_sched_t *pucch);
 initial_pucch_resource_t get_initial_pucch_resource(const int idx);
 void multiplex_pucch_resource(NR_UE_MAC_INST_t *mac, PUCCH_sched_t *pucch, int num_res);
-uint32_t get_backoff_indicator(int idx);
 int16_t get_pucch_tx_power_ue(NR_UE_MAC_INST_t *mac,
                               int scs,
                               NR_PUCCH_Config_t *pucch_Config,
@@ -307,10 +306,6 @@ void nr_ra_failed(NR_UE_MAC_INST_t *mac, uint8_t CC_id, NR_PRACH_RESOURCES_t *pr
 
 void nr_ra_succeeded(NR_UE_MAC_INST_t *mac, const uint8_t gNB_index, const frame_t frame, const int slot);
 
-int16_t nr_get_RA_window_2Step(const NR_MsgA_ConfigCommon_r16_t *msgA_ConfigCommon_r16);
-
-int16_t nr_get_RA_window_4Step(const NR_RACH_ConfigCommon_t *rach_ConfigCommon);
-
 void nr_get_RA_window(NR_UE_MAC_INST_t *mac);
 
 /*@mac pointer to MAC instance
@@ -336,6 +331,8 @@ NR_UE_L2_STATE_t nr_ue_get_sync_state(module_id_t mod_id);
 
 int16_t get_prach_tx_power(NR_UE_MAC_INST_t *mac);
 void schedule_RA_after_SR_failure(NR_UE_MAC_INST_t *mac);
+void nr_rar_not_successful(NR_UE_MAC_INST_t *mac);
+void ra_resource_selection(NR_UE_MAC_INST_t *mac);
 void nr_Msg3_transmitted(NR_UE_MAC_INST_t *mac, uint8_t CC_id, frame_t frameP, slot_t slotP, uint8_t gNB_id);
 void trigger_MAC_UE_RA(NR_UE_MAC_INST_t *mac, dci_pdu_rel15_t *pdcch_order);
 void nr_get_Msg3_MsgA_PUSCH_payload(NR_UE_MAC_INST_t *mac, uint8_t *buf, int TBS_max);
diff --git a/openair2/LAYER2/NR_MAC_UE/mac_tables.c b/openair2/LAYER2/NR_MAC_UE/mac_tables.c
index bd4cc6d8f3..a313600609 100644
--- a/openair2/LAYER2/NR_MAC_UE/mac_tables.c
+++ b/openair2/LAYER2/NR_MAC_UE/mac_tables.c
@@ -412,30 +412,6 @@ static const uint8_t table_7_3_2_3_3_4_twoCodeword[6][14] = {
   {2,1,1,1,1,0,0,1,1,1,1,0,0,2},
 };
 
-// table 7.2-1 TS 38.321
-static const uint32_t table_7_2_1[16] = {
-  5,    // row index 0
-  10,   // row index 1
-  20,   // row index 2
-  30,   // row index 3
-  40,   // row index 4
-  60,   // row index 5
-  80,   // row index 6
-  120,  // row index 7
-  160,  // row index 8
-  240,  // row index 9
-  320,  // row index 10
-  480,  // row index 11
-  960,  // row index 12
-  1920, // row index 13
-};
-
-uint32_t get_backoff_indicator(int idx)
-{
-  AssertFatal(idx < 16, "Backoff indicator index %d exeeding table size\n", idx);
-  return table_7_2_1[idx];
-}
-
 static inline uint16_t packBits(const uint8_t *toPack, const int nb)
 {
   int res = 0;
diff --git a/openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c b/openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c
index 9a4caa7038..02afecec81 100644
--- a/openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c
+++ b/openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c
@@ -450,7 +450,7 @@ static void select_prach_occasion(RA_config_t *ra,
     seed = 1;
   } else {
     // & to truncate the int64_t and keep only the LSB bits, up to sizeof(int)
-    seed = (unsigned int) (rdtsc_oai() & ~0);
+    seed = (unsigned int)(rdtsc_oai() & ~0);
   }
 
   int num_ros_per_ssb = 0;
@@ -630,7 +630,7 @@ static void ra_preamble_msga_transmission(RA_config_t *ra, int scs)
 }
 
 // 38.321 Section 5.1.2 Random Access Resource selection
-static void ra_resource_selection(NR_UE_MAC_INST_t *mac)
+void ra_resource_selection(NR_UE_MAC_INST_t *mac)
 {
   configure_ra_preamble(mac);
   const NR_UE_UL_BWP_t *current_UL_BWP = mac->current_UL_BWP;
@@ -640,6 +640,189 @@ static void ra_resource_selection(NR_UE_MAC_INST_t *mac)
   ra_preamble_msga_transmission(&mac->ra, mu);
 }
 
+static int nr_get_RA_window_2Step_v17(long msgB_ResponseWindow)
+{
+  switch (msgB_ResponseWindow) {
+    case NR_RACH_ConfigGenericTwoStepRA_r16__ext1__msgB_ResponseWindow_v1700_sl240:
+      return 240;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__ext1__msgB_ResponseWindow_v1700_sl640:
+      return 640;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__ext1__msgB_ResponseWindow_v1700_sl960:
+      return 960;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__ext1__msgB_ResponseWindow_v1700_sl1280:
+      return 1280;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__ext1__msgB_ResponseWindow_v1700_sl1920:
+      return 1920;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__ext1__msgB_ResponseWindow_v1700_sl2560:
+      return 2590;
+    default:
+      AssertFatal(false, "illegal msgB_responseWindow value %ld\n", msgB_ResponseWindow);
+      break;
+  }
+  return 0;
+}
+
+static int nr_get_RA_window_2Step_v16(long msgB_ResponseWindow)
+{
+  switch (msgB_ResponseWindow) {
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl1:
+      return 1;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl2:
+      return 2;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl4:
+      return 4;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl8:
+      return 8;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl10:
+      return 10;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl20:
+      return 20;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl40:
+      return 40;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl80:
+      return 80;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl160:
+      return 160;
+      break;
+    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl320:
+      return 360;
+      break;
+    default:
+      AssertFatal(false, "illegal msgB_responseWindow value %ld\n", msgB_ResponseWindow);
+      break;
+  }
+  return 0;
+}
+
+static int nr_get_RA_window_4Step_v16(long ra_ResponseWindow)
+{
+  switch (ra_ResponseWindow) {
+    case NR_RACH_ConfigGeneric__ext1__ra_ResponseWindow_v1610_sl60:
+      return 60;
+    case NR_RACH_ConfigGeneric__ext1__ra_ResponseWindow_v1610_sl160:
+      return 160;
+    default:
+      AssertFatal(false, "illegal ra_ResponseWindow value %ld\n", ra_ResponseWindow);
+  }
+  return 0;
+}
+
+static int nr_get_RA_window_4Step_v17(long ra_ResponseWindow)
+{
+  switch (ra_ResponseWindow) {
+    case NR_RACH_ConfigGeneric__ext2__ra_ResponseWindow_v1700_sl240:
+      return 240;
+    case NR_RACH_ConfigGeneric__ext2__ra_ResponseWindow_v1700_sl320:
+      return 320;
+    case NR_RACH_ConfigGeneric__ext2__ra_ResponseWindow_v1700_sl640:
+      return 640;
+    case NR_RACH_ConfigGeneric__ext2__ra_ResponseWindow_v1700_sl960:
+      return 960;
+    case NR_RACH_ConfigGeneric__ext2__ra_ResponseWindow_v1700_sl1280:
+      return 1280;
+    case NR_RACH_ConfigGeneric__ext2__ra_ResponseWindow_v1700_sl1920:
+      return 1920;
+    case NR_RACH_ConfigGeneric__ext2__ra_ResponseWindow_v1700_sl2560:
+      return 2590;
+    default:
+      AssertFatal(false, "illegal msgB_responseWindow value %ld\n", ra_ResponseWindow);
+  }
+  return 0;
+}
+
+static int nr_get_RA_window_4Step(long ra_ResponseWindow)
+{
+  switch (ra_ResponseWindow) {
+    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl1:
+      return 1;
+      break;
+    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl2:
+      return 2;
+      break;
+    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl4:
+      return 4;
+      break;
+    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl8:
+      return 8;
+      break;
+    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl10:
+      return 10;
+      break;
+    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl20:
+      return 20;
+      break;
+    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl40:
+      return 40;
+      break;
+    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl80:
+      return 80;
+      break;
+    default:
+      AssertFatal(false, "illegal ra_ResponseWindow value %ld\n", ra_ResponseWindow);
+      break;
+  }
+  return 0;
+}
+
+static void setup_ra_response_window(RA_config_t *ra,
+                                     int slots_per_frame,
+                                     NR_NTN_Config_r17_t *ntn_Config_r17,
+                                     NR_RACH_ConfigGeneric_t *configGeneric,
+                                     NR_RACH_ConfigGenericTwoStepRA_r16_t *twostep,
+                                     ntn_timing_advance_componets_t *ntn_ta)
+{
+  int respwind_value = 0;
+  if (ra->ra_type == RA_2_STEP) {
+    long *msgB_ResponseWindow = twostep->msgB_ResponseWindow_r16;
+    if (msgB_ResponseWindow)
+      respwind_value = nr_get_RA_window_2Step_v16(*msgB_ResponseWindow);
+    if (twostep->ext1 && twostep->ext1->msgB_ResponseWindow_v1700) {
+      AssertFatal(msgB_ResponseWindow == NULL,
+                  "The network does not configure msgB-ResponseWindow-r16 simultaneously with msgB-ResponseWindow-v1700\n");
+      msgB_ResponseWindow = twostep->ext1->msgB_ResponseWindow_v1700;
+      if (msgB_ResponseWindow)
+        respwind_value = nr_get_RA_window_2Step_v17(*msgB_ResponseWindow);
+    }
+    // The network configures a value lower than or equal to 40ms
+    int slots_40ms = 4 * slots_per_frame;
+    AssertFatal(respwind_value != 0 && respwind_value <= slots_40ms, "Invalid MSGB response window value\n");
+  } else {
+    AssertFatal(ra->ra_type == RA_4_STEP, "Invalid RA type\n");
+    long *response_window = NULL;
+    if (configGeneric->ext1 && configGeneric->ext1->ra_ResponseWindow_v1610)
+      respwind_value = nr_get_RA_window_4Step_v16(*configGeneric->ext1->ra_ResponseWindow_v1610);
+    if (configGeneric->ext2 && configGeneric->ext2->ra_ResponseWindow_v1700) {
+      AssertFatal(response_window == NULL, "ra_ResponseWindow_v1610 and ra_ResponseWindow_v1700 are mutually exclusive\n");
+      respwind_value = nr_get_RA_window_4Step_v17(*configGeneric->ext2->ra_ResponseWindow_v1700);
+    }
+    if (!response_window)
+      respwind_value = nr_get_RA_window_4Step(configGeneric->ra_ResponseWindow);
+    // The network configures a value lower than or equal to 10ms
+    AssertFatal(respwind_value != 0 && respwind_value <= slots_per_frame, "Invalid RAR response window value\n");
+  }
+
+  int ta_Common_slots = 0;
+  if (ntn_Config_r17) {
+    const double ta_Common_ms = GET_COMPLETE_TIME_ADVANCE_MS(ntn_ta);
+    ta_Common_slots = (int)ceil(ta_Common_ms * slots_per_frame / 10);
+  }
+
+  nr_timer_setup(&ra->response_window_timer, respwind_value + ta_Common_slots, 1);
+}
+
 // Random Access procedure initialization as per 5.1.1 and initialization of variables specific
 // to Random Access type as specified in clause 5.1.1a (3GPP TS 38.321 version 16.2.1 Release 16)
 bool init_RA(NR_UE_MAC_INST_t *mac, int frame)
@@ -704,8 +887,6 @@ bool init_RA(NR_UE_MAC_INST_t *mac, int frame)
   prach_resources->preamble_tx_counter = 1;
   // set the PREAMBLE_POWER_RAMPING_COUNTER to 1
   prach_resources->preamble_power_ramping_cnt = 1;
-  // set the PREAMBLE_BACKOFF to 0 ms TODO to be set as a timer?
-  prach_resources->preamble_backoff = 0;
   // set POWER_OFFSET_2STEP_RA to 0 dB
   prach_resources->power_offset_2step = 0;
 
@@ -826,7 +1007,7 @@ bool init_RA(NR_UE_MAC_INST_t *mac, int frame)
   else
     prach_resources->preamble_power_ramping_step = rach_ConfigGeneric->powerRampingStep << 1;
 
-  prach_resources->scaling_factor_bi = 1;
+  ra->scaling_factor_bi = 1;
 
   if (ra->ra_type == RA_2_STEP && twostep_generic && twostep_generic->msgA_PreambleReceivedTargetPower_r16)
     ra->preambleReceivedTargetPower_config = *twostep_generic->msgA_PreambleReceivedTargetPower_r16;
@@ -863,9 +1044,6 @@ bool init_RA(NR_UE_MAC_INST_t *mac, int frame)
   else
     ra->msg3_deltaPreamble = mac->current_UL_BWP->msg3_DeltaPreamble ? *mac->current_UL_BWP->msg3_DeltaPreamble << 1 : 0;
 
-  ra->RA_RAPID_found = 0;
-  ra->RA_backoff_cnt = 0;
-  ra->RA_window_cnt = -1;
   ra->new_ssb = false;
 
   if (ra->ra_type == RA_2_STEP && twostep_generic && twostep_generic->msgA_PRACH_ConfigurationIndex_r16)
@@ -882,18 +1060,16 @@ bool init_RA(NR_UE_MAC_INST_t *mac, int frame)
   else
     ra->num_fd_occasions = 1 << rach_ConfigGeneric->msg1_FDM;
 
+  setup_ra_response_window(ra,
+                           mac->frame_structure.numb_slots_frame,
+                           mac->sc_info.ntn_Config_r17,
+                           rach_ConfigGeneric,
+                           twostep_generic,
+                           &mac->ntn_ta);
+  ra->start_response_window = false;
   return true;
 }
 
-static void nr_get_prach_resources(NR_UE_MAC_INST_t *mac, NR_PRACH_RESOURCES_t *prach_resources)
-{
-  const int ul_mu = mac->current_UL_BWP->scs;
-  const int mu = nr_get_prach_or_ul_mu(mac->current_UL_BWP->msgA_ConfigCommon_r16, mac->current_UL_BWP->rach_ConfigCommon, ul_mu);
-  if (prach_resources->preamble_tx_counter > 1)
-    prach_resources->preamble_power_ramping_cnt++;
-  prach_resources->ra_preamble_rx_target_power = get_ra_preamble_rx_target_power(&mac->ra, mu);
-}
-
 void nr_Msg3_transmitted(NR_UE_MAC_INST_t *mac, uint8_t CC_id, frame_t frameP, slot_t slotP, uint8_t gNB_id)
 {
   RA_config_t *ra = &mac->ra;
@@ -1012,48 +1188,15 @@ void nr_ue_manage_ra_procedure(NR_UE_MAC_INST_t *mac, int CC_id, frame_t frame,
 
   LOG_D(NR_MAC, "[UE %d][%d.%d]: ra_state %d, RA_active %d\n", mac->ue_id, frame, nr_slot_tx, ra->ra_state, ra->RA_active);
 
-  if (ra->ra_state < nrRA_SUCCEEDED) {
-    if (ra->RA_window_cnt != -1) { // RACH is active
-
-      LOG_D(MAC, "[%d.%d] RA is active: RA window count %d, RA backoff count %d\n", frame, nr_slot_tx, ra->RA_window_cnt, ra->RA_backoff_cnt);
-
-      if (ra->RA_BI_found){
-        prach_resources->preamble_backoff = prach_resources->scaling_factor_bi * ra->RA_backoff_indicator;
-      } else {
-        prach_resources->preamble_backoff = 0;
-      }
-
-      if (ra->RA_window_cnt >= 0 && ra->RA_RAPID_found == 1) {
-
-        if(ra->cfra) {
-          // Reset RA_active flag: it disables Msg3 retransmission (8.3 of TS 38.213)
-          nr_ra_succeeded(mac, gNB_id, frame, nr_slot_tx);
-        }
-
-      } else if (ra->RA_window_cnt == 0 && !ra->RA_RAPID_found && ra->ra_state != nrRA_WAIT_MSGB) {
-        LOG_W(MAC, "[UE %d][%d:%d] RAR reception failed \n", mac->ue_id, frame, nr_slot_tx);
-
-        nr_ra_failed(mac, CC_id, prach_resources, frame, nr_slot_tx);
-
-      } else if (ra->RA_window_cnt > 0) {
-
-        LOG_D(MAC, "[UE %d][%d.%d]: RAR not received yet (RA window count %d) \n", mac->ue_id, frame, nr_slot_tx, ra->RA_window_cnt);
-
-        // Fill in preamble and PRACH resources
-        ra->RA_window_cnt--;
-        if (ra->ra_state == nrRA_GENERATE_PREAMBLE) {
-          nr_get_prach_resources(mac, prach_resources);
-        }
-      } else if (ra->RA_backoff_cnt > 0) {
-
-        LOG_D(MAC, "[UE %d][%d.%d]: RAR not received yet (RA backoff count %d) \n", mac->ue_id, frame, nr_slot_tx, ra->RA_backoff_cnt);
-
-        ra->RA_backoff_cnt--;
-
-        if ((ra->RA_backoff_cnt > 0 && ra->ra_state == nrRA_GENERATE_PREAMBLE) || ra->RA_backoff_cnt == 0) {
-          nr_get_prach_resources(mac, prach_resources);
-        }
-      }
+  if (nr_timer_is_active(&ra->RA_backoff_timer)) {
+    // if the criteria (as defined in clause 5.1.2) to select contention-free Random Access Resources
+    // is met during the backoff time
+    // TODO verify what does this mean
+    if (ra->cfra) {
+      // perform the Random Access Resource selection procedure
+      nr_timer_stop(&ra->RA_backoff_timer);
+      mac->ra.ra_state = nrRA_GENERATE_PREAMBLE;
+      ra_resource_selection(mac);
     }
   }
 
@@ -1062,102 +1205,6 @@ void nr_ue_manage_ra_procedure(NR_UE_MAC_INST_t *mac, int CC_id, frame_t frame,
   }
 }
 
-int16_t nr_get_RA_window_2Step(const NR_MsgA_ConfigCommon_r16_t *msgA_ConfigCommon_r16)
-{
-  int16_t ra_ResponseWindow = *msgA_ConfigCommon_r16->rach_ConfigCommonTwoStepRA_r16
-                              .rach_ConfigGenericTwoStepRA_r16.msgB_ResponseWindow_r16;
-
-  switch (ra_ResponseWindow) {
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl1:
-      return 1;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl2:
-      return 2;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl4:
-      return 4;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl8:
-      return 8;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl10:
-      return 10;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl20:
-      return 20;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl40:
-      return 40;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl80:
-      return 80;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl160:
-      return 160;
-      break;
-    case NR_RACH_ConfigGenericTwoStepRA_r16__msgB_ResponseWindow_r16_sl320:
-      return 360;
-      break;
-    default:
-      AssertFatal(false, "illegal msgB_responseWindow value %d\n", ra_ResponseWindow);
-      break;
-  }
-  return 0;
-}
-
-int16_t nr_get_RA_window_4Step(const NR_RACH_ConfigCommon_t *rach_ConfigCommon)
-{
-  int16_t ra_ResponseWindow = rach_ConfigCommon->rach_ConfigGeneric.ra_ResponseWindow;
-
-  switch (ra_ResponseWindow) {
-    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl1:
-      return 1;
-      break;
-    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl2:
-      return 2;
-      break;
-    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl4:
-      return 4;
-      break;
-    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl8:
-      return 8;
-      break;
-    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl10:
-      return 10;
-      break;
-    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl20:
-      return 20;
-      break;
-    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl40:
-      return 40;
-      break;
-    case NR_RACH_ConfigGeneric__ra_ResponseWindow_sl80:
-      return 80;
-      break;
-    default:
-      AssertFatal(false, "illegal ra_ResponseWindow value %d\n", ra_ResponseWindow);
-      break;
-  }
-  return 0;
-}
-
-void nr_get_RA_window(NR_UE_MAC_INST_t *mac)
-{
-  RA_config_t *ra = &mac->ra;
-  NR_RACH_ConfigCommon_t *setup = mac->current_UL_BWP->rach_ConfigCommon;
-  AssertFatal(&setup->rach_ConfigGeneric != NULL, "In %s: FATAL! rach_ConfigGeneric is NULL...\n", __FUNCTION__);
-  const double ta_Common_ms = GET_COMPLETE_TIME_ADVANCE_MS(&mac->ntn_ta);
-  int slots_per_frame = mac->frame_structure.numb_slots_frame;
-  const int slots_per_ms = slots_per_frame / 10;
-  const int ra_Offset_slots = ra->RA_offset * slots_per_frame;
-  const int ta_Common_slots = (int)ceil(ta_Common_ms * slots_per_ms);
-
-  ra->RA_window_cnt = ra_Offset_slots + ta_Common_slots; // taking into account the 2 frames gap introduced by OAI gNB
-
-  ra->RA_window_cnt += ra->ra_type == RA_2_STEP ? nr_get_RA_window_2Step(mac->current_UL_BWP->msgA_ConfigCommon_r16)
-                                                : nr_get_RA_window_4Step(mac->current_UL_BWP->rach_ConfigCommon);
-}
-
 ////////////////////////////////////////////////////////////////////////////
 /////////* Random Access Contention Resolution (5.1.35 TS 38.321) */////////
 ////////////////////////////////////////////////////////////////////////////
@@ -1188,7 +1235,6 @@ void nr_ra_succeeded(NR_UE_MAC_INST_t *mac, const uint8_t gNB_index, const frame
 
   if (ra->cfra) {
     LOG_I(MAC, "[UE %d][%d.%d][RAPROC] RA procedure succeeded. CFRA: RAR successfully received.\n", mac->ue_id, frame, slot);
-    ra->RA_window_cnt = -1;
   } else if (ra->ra_type == RA_2_STEP) {
     LOG_A(MAC,
           "[UE %d][%d.%d][RAPROC] 2-Step RA procedure succeeded. CBRA: Contention Resolution is successful.\n",
@@ -1210,7 +1256,6 @@ void nr_ra_succeeded(NR_UE_MAC_INST_t *mac, const uint8_t gNB_index, const frame
     LOG_D(MAC, "[UE %d][%d.%d] CBRA: cleared contention resolution timer...\n", mac->ue_id, frame, slot);
   }
 
-  LOG_D(MAC, "[UE %d] clearing RA_active flag...\n", mac->ue_id);
   ra->RA_active = false;
   ra->msg3_C_RNTI = false;
   ra->ra_state = nrRA_SUCCEEDED;
@@ -1219,6 +1264,35 @@ void nr_ra_succeeded(NR_UE_MAC_INST_t *mac, const uint8_t gNB_index, const frame
   nr_mac_rrc_ra_ind(mac->ue_id, frame, true);
 }
 
+void nr_rar_not_successful(NR_UE_MAC_INST_t *mac)
+{
+  LOG_W(MAC, "[UE %d] RAR reception failed\n", mac->ue_id);
+  RA_config_t *ra = &mac->ra;
+  NR_PRACH_RESOURCES_t *prach_resources = &ra->prach_resources;
+  prach_resources->preamble_tx_counter++;
+  bool ra_completed = false;
+  if (prach_resources->preamble_tx_counter == ra->preambleTransMax + 1) {
+    // if the Random Access Preamble is transmitted on the SpCell
+    // TODO to be verified, this means SA if I'm not mistaken
+    if (IS_SA_MODE(get_softmodem_params())) {
+      // TODO indicate a Random Access problem to upper layers
+    } else {
+      // if the Random Access Preamble is transmitted on an SCell:
+      // consider the Random Access procedure unsuccessfully completed.
+      ra_completed = true;
+      ra->ra_state = nrRA_UE_IDLE;
+    }
+  }
+  if (!ra_completed) {
+    // select a random backoff time according to a uniform distribution
+    // between 0 and the PREAMBLE_BACKOFF
+    uint32_t seed = (unsigned int)(rdtsc_oai() & ~0);
+    uint32_t random_backoff = rand_r(&seed) % ra->RA_backoff_limit; // in slots
+    nr_timer_setup(&ra->RA_backoff_timer, random_backoff, 1);
+    nr_timer_start(&ra->RA_backoff_timer);
+  }
+}
+
 // Handling failure of RA procedure @ MAC layer
 // according to section 5 of 3GPP TS 38.321 version 16.2.1 Release 16
 // todo:
@@ -1226,17 +1300,6 @@ void nr_ra_succeeded(NR_UE_MAC_INST_t *mac, const uint8_t gNB_index, const frame
 void nr_ra_failed(NR_UE_MAC_INST_t *mac, uint8_t CC_id, NR_PRACH_RESOURCES_t *prach_resources, frame_t frame, int slot)
 {
   RA_config_t *ra = &mac->ra;
-  // Random seed generation
-  unsigned int seed;
-
-  if (IS_SOFTMODEM_IQPLAYER || IS_SOFTMODEM_IQRECORDER) {
-    // Overwrite seed with non-random seed for IQ player/recorder
-    seed = 1;
-  } else {
-    // & to truncate the int64_t and keep only the LSB bits, up to sizeof(int)
-    seed = (unsigned int)(rdtsc_oai() & ~0);
-  }
-  
   ra->ra_PreambleIndex = -1;
   ra->ra_state = nrRA_UE_IDLE;
 
@@ -1255,13 +1318,10 @@ void nr_ra_failed(NR_UE_MAC_INST_t *mac, uint8_t CC_id, NR_PRACH_RESOURCES_t *pr
           slot,
           ra->preambleTransMax);
 
-    ra->RA_backoff_cnt = rand_r(&seed) % (prach_resources->preamble_backoff + 1);
     prach_resources->preamble_tx_counter = 1;
     prach_resources->preamble_power_ramping_step += 2; // 2 dB increment
     prach_resources->ra_preamble_rx_target_power = get_ra_preamble_rx_target_power(ra, mac->current_UL_BWP->scs);
 
-  } else {
-    nr_get_RA_window(mac);
   }
 }
 
diff --git a/openair2/LAYER2/NR_MAC_UE/nr_ue_dci_configuration.c b/openair2/LAYER2/NR_MAC_UE/nr_ue_dci_configuration.c
index b2fcab87c3..237838e4dc 100644
--- a/openair2/LAYER2/NR_MAC_UE/nr_ue_dci_configuration.c
+++ b/openair2/LAYER2/NR_MAC_UE/nr_ue_dci_configuration.c
@@ -563,6 +563,12 @@ void ue_dci_configuration(NR_UE_MAC_INST_t *mac, fapi_nr_dl_config_request_t *dl
   if (mac->state == UE_PERFORMING_RA && mac->ra.ra_state >= nrRA_WAIT_RAR) {
     // if RA is ongoing use RA search space
     if (is_ss_monitor_occasion(frame, slot, slots_per_frame, pdcch_config->ra_SS)) {
+      // The RA response window starts at the first symbol of the earliest CORESET
+      // the UE is configured to receive PDCCH for Type1-PDCCH CSS set
+      if (mac->ra.start_response_window) {
+        nr_timer_start(&mac->ra.response_window_timer);
+        mac->ra.start_response_window = false;
+      }
       nr_rnti_type_t rnti_type = 0;
       if (mac->ra.ra_type == RA_4_STEP) {
         rnti_type = mac->ra.ra_state == nrRA_WAIT_RAR ? TYPE_RA_RNTI_ : TYPE_TC_RNTI_;
diff --git a/openair2/LAYER2/NR_MAC_UE/nr_ue_power_procedures.c b/openair2/LAYER2/NR_MAC_UE/nr_ue_power_procedures.c
index 0c024560d7..9db464f015 100644
--- a/openair2/LAYER2/NR_MAC_UE/nr_ue_power_procedures.c
+++ b/openair2/LAYER2/NR_MAC_UE/nr_ue_power_procedures.c
@@ -492,9 +492,7 @@ int get_pusch_tx_power_ue(NR_UE_MAC_INST_t *mac,
     if (current_UL_BWP->msg3_DeltaPreamble) {
       DELTA_PREAMBLE_MSG3 = *current_UL_BWP->msg3_DeltaPreamble;
     }
-    NR_RACH_ConfigCommon_t *nr_rach_ConfigCommon = current_UL_BWP->rach_ConfigCommon;
-    long preambleReceivedTargetPower = nr_rach_ConfigCommon->rach_ConfigGeneric.preambleReceivedTargetPower;
-    int P_O_PRE = preambleReceivedTargetPower;
+    int P_O_PRE = mac->ra.prach_resources.ra_preamble_rx_target_power;
     P_O_NOMINAL_PUSCH = P_O_PRE + DELTA_PREAMBLE_MSG3;
 
     if (has_pusch_power_control_config && pusch_Config->pusch_PowerControl->msg3_Alpha) {
diff --git a/openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c b/openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c
index 54f047f46d..a77067395f 100644
--- a/openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c
+++ b/openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c
@@ -59,6 +59,25 @@
 // #define DEBUG_MIB
 // #define ENABLE_MAC_PAYLOAD_DEBUG 1
 // #define DEBUG_RAR
+
+// table 7.2-1 TS 38.321
+const uint16_t table_7_2_1[16] = {
+    5,    // row index 0
+    10,   // row index 1
+    20,   // row index 2
+    30,   // row index 3
+    40,   // row index 4
+    60,   // row index 5
+    80,   // row index 6
+    120,  // row index 7
+    160,  // row index 8
+    240,  // row index 9
+    320,  // row index 10
+    480,  // row index 11
+    960,  // row index 12
+    1920, // row index 13
+};
+
 /* TS 36.213 Table 9.2.3-3: Mapping of values for one HARQ-ACK bit to sequences */
 static const int sequence_cyclic_shift_1_harq_ack_bit[2]
 /*        HARQ-ACK Value        0    1 */
@@ -701,7 +720,7 @@ static int nr_ue_process_dci_dl_10(NR_UE_MAC_INST_t *mac,
       dlsch_pdu->SubcarrierSpacing = mac->mib->subCarrierSpacingCommon + 2;
   } else {
     dlsch_pdu->SubcarrierSpacing = current_DL_BWP->scs;
-    if (mac->ra.RA_window_cnt >= 0 && rnti_type == TYPE_RA_RNTI_) {
+    if (nr_timer_is_active(&mac->ra.response_window_timer) && rnti_type == TYPE_RA_RNTI_) {
       dl_conf_req->pdu_type = FAPI_NR_DL_CONFIG_TYPE_RA_DLSCH;
     } else {
       dl_conf_req->pdu_type = FAPI_NR_DL_CONFIG_TYPE_DLSCH;
@@ -3414,11 +3433,11 @@ static bool check_ra_contention_resolution(const uint8_t *pdu, const uint8_t *co
 }
 
 static int nr_ue_validate_successrar(uint8_t *pduP,
-                              int32_t pdu_len,
-                              NR_UE_MAC_INST_t *mac,
-                              uint8_t gNB_index,
-                              frame_t frameP,
-                              int slot)
+                                     int32_t pdu_len,
+                                     NR_UE_MAC_INST_t *mac,
+                                     uint8_t gNB_index,
+                                     frame_t frameP,
+                                     int slot)
 {
   // TS 38.321 - Figure 6.1.5a-1: BI MAC subheader
   // TS 38.321 - Figure 6.1.5a-3: SuccessRAR MAC subheader
@@ -3426,6 +3445,7 @@ static int nr_ue_validate_successrar(uint8_t *pduP,
   uint8_t E = 1;
   uint8_t cont_res_id[6];
   RA_config_t *ra = &mac->ra;
+  ra->RA_backoff_limit = 0;
 
   while (n < pdu_len && E) {
     E = (pduP[n] >> 7) & 0x1;
@@ -3433,7 +3453,9 @@ static int nr_ue_validate_successrar(uint8_t *pduP,
     if (SUCESS_RAR_header_T1 == 0) { // T2 exist
       int SUCESS_RAR_header_T2 = (pduP[n] >> 5) & 0x1;
       if (SUCESS_RAR_header_T2 == 0) { // BI
-        ra->RA_backoff_indicator = pduP[n] & 0x0F;
+        int bi_ms = table_7_2_1[(pduP[n] & 0x0F)] * ra->scaling_factor_bi;
+        int slots_per_ms = mac->frame_structure.numb_slots_frame / 10;
+        ra->RA_backoff_limit = bi_ms * slots_per_ms;
         n++;
       } else { // S
         n++;
@@ -3476,6 +3498,7 @@ static int nr_ue_validate_successrar(uint8_t *pduP,
         bool ra_success = check_ra_contention_resolution(cont_res_id, ra->cont_res_id);
 
         if (ra->RA_active && ra_success) {
+          nr_timer_stop(&ra->response_window_timer);
           nr_ra_succeeded(mac, gNB_index, frameP, slot);
         } else if (!ra_success) {
           // nr_ra_failed(mac, CC_id, &ra->prach_resources, frameP, slot);
@@ -3841,6 +3864,115 @@ int nr_write_ce_ulsch_pdu(uint8_t *mac_ce,
   return mac_ce - pdu;
 }
 
+static void handle_rar_reception(NR_UE_MAC_INST_t *mac, nr_downlink_indication_t *dlinfo, NR_MAC_RAR *rar, frame_t frame, int slot)
+{
+  RAR_grant_t rar_grant;
+  RA_config_t *ra = &mac->ra;
+#ifdef DEBUG_RAR
+  // CSI
+  unsigned char csi_req = (unsigned char)(rar->UL_GRANT_4 & 0x01);
+#endif
+
+  // TPC
+  unsigned char tpc_command = (unsigned char)((rar->UL_GRANT_4 >> 1) & 0x07);
+  ra->Msg3_TPC = (tpc_command << 1) - 6;
+
+  // MCS
+  rar_grant.mcs = (unsigned char)(rar->UL_GRANT_4 >> 4);
+  // time alloc
+  rar_grant.Msg3_t_alloc = (unsigned char)(rar->UL_GRANT_3 & 0x0f);
+  // frequency alloc
+  rar_grant.Msg3_f_alloc = (uint16_t)((rar->UL_GRANT_3 >> 4) | (rar->UL_GRANT_2 << 4) | ((rar->UL_GRANT_1 & 0x03) << 12));
+  // frequency hopping
+  rar_grant.freq_hopping = (unsigned char)(rar->UL_GRANT_1 >> 2);
+
+  // Schedule Msg3
+  const NR_UE_UL_BWP_t *current_UL_BWP = mac->current_UL_BWP;
+  const NR_UE_DL_BWP_t *current_DL_BWP = mac->current_DL_BWP;
+  const NR_BWP_PDCCH_t *pdcch_config = &mac->config_BWP_PDCCH[current_DL_BWP->bwp_id];
+  NR_tda_info_t tda_info = get_ul_tda_info(current_UL_BWP,
+                                           *pdcch_config->ra_SS->controlResourceSetId,
+                                           pdcch_config->ra_SS->searchSpaceType->present,
+                                           TYPE_RA_RNTI_,
+                                           rar_grant.Msg3_t_alloc);
+  if (!tda_info.valid_tda || tda_info.nrOfSymbols == 0) {
+    LOG_E(MAC, "Cannot schedule Msg3. Something wrong in TDA information\n");
+    return;
+  }
+  frame_t frame_tx = 0;
+  int slot_tx = 0;
+  const int ntn_ue_koffset = GET_NTN_UE_K_OFFSET(&mac->ntn_ta, mac->current_UL_BWP->scs);
+  int ret = nr_ue_pusch_scheduler(mac, 1, frame, slot, &frame_tx, &slot_tx, tda_info.k2 + ntn_ue_koffset);
+
+  // TA command
+  // if the timeAlignmentTimer associated with this TAG is not running
+  if (!nr_timer_is_active(&mac->time_alignment_timer)) {
+    const int ta = rar->TA2 + (rar->TA1 << 5);
+    set_time_alignment(mac, ta, rar_ta, frame_tx, slot_tx);
+    LOG_W(MAC, "received TA command %d\n", 31 + ta);
+  }
+  // else ignore the received Timing Advance Command
+
+#ifdef DEBUG_RAR
+  LOG_I(NR_MAC, "rarh->E = 0x%x\n", rarh->E);
+  LOG_I(NR_MAC, "rarh->T = 0x%x\n", rarh->T);
+  LOG_I(NR_MAC, "rarh->RAPID = 0x%x (%i)\n", rarh->RAPID, rarh->RAPID);
+
+  LOG_I(NR_MAC, "rar->R = 0x%x\n", rar->R);
+  LOG_I(NR_MAC, "rar->TA1 = 0x%x\n", rar->TA1);
+
+  LOG_I(NR_MAC, "rar->TA2 = 0x%x\n", rar->TA2);
+  LOG_I(NR_MAC, "rar->UL_GRANT_1 = 0x%x\n", rar->UL_GRANT_1);
+
+  LOG_I(NR_MAC, "rar->UL_GRANT_2 = 0x%x\n", rar->UL_GRANT_2);
+  LOG_I(NR_MAC, "rar->UL_GRANT_3 = 0x%x\n", rar->UL_GRANT_3);
+  LOG_I(NR_MAC, "rar->UL_GRANT_4 = 0x%x\n", rar->UL_GRANT_4);
+
+  LOG_I(NR_MAC, "rar->TCRNTI_1 = 0x%x\n", rar->TCRNTI_1);
+  LOG_I(NR_MAC, "rar->TCRNTI_2 = 0x%x\n", rar->TCRNTI_2);
+
+  LOG_I(NR_MAC,
+        "[%d.%d]: [UE %d] Received RAR with t_alloc %d f_alloc %d ta_command %d mcs %d freq_hopping %d tpc_command %d\n",
+        frame,
+        slot,
+        mac->ue_id,
+        rar_grant.Msg3_t_alloc,
+        rar_grant.Msg3_f_alloc,
+        ta_command,
+        rar_grant.mcs,
+        rar_grant.freq_hopping,
+        tpc_command);
+#endif
+
+  if (ret != -1) {
+    uint16_t rnti = mac->crnti;
+    // Upon successful reception, set the T-CRNTI to the RAR value
+    // if the RA preamble is selected among the contention-based RA Preambles
+    if (!ra->cfra) {
+      ra->t_crnti = rar->TCRNTI_2 + (rar->TCRNTI_1 << 8);
+      rnti = ra->t_crnti;
+      if (!ra->msg3_C_RNTI)
+        nr_mac_rrc_msg3_ind(mac->ue_id, rnti, dlinfo->gNB_index);
+    }
+    fapi_nr_ul_config_request_pdu_t *pdu = lockGet_ul_config(mac, frame_tx, slot_tx, FAPI_NR_UL_CONFIG_TYPE_PUSCH);
+    if (!pdu)
+      return;
+    // Config Msg3 PDU
+    int ret = nr_config_pusch_pdu(mac,
+                                  &tda_info,
+                                  &pdu->pusch_config_pdu,
+                                  NULL,
+                                  NULL,
+                                  &rar_grant,
+                                  rnti,
+                                  NR_SearchSpace__searchSpaceType_PR_common,
+                                  NR_DCI_NONE);
+    if (ret != 0)
+      remove_ul_config_last_item(pdu);
+    release_ul_config(pdu, false);
+  }
+}
+
 /////////////////////////////////////
 //    Random Access Response PDU   //
 //         TS 38.213 ch 8.2        //
@@ -3885,13 +4017,10 @@ static void nr_ue_process_rar(NR_UE_MAC_INST_t *mac, nr_downlink_indication_t *d
   }
 
   RA_config_t *ra = &mac->ra;
+  ra->t_crnti = 0;
   uint8_t n_subPDUs  = 0;  // number of RAR payloads
   uint8_t n_subheaders = 0;  // number of MAC RAR subheaders
   uint8_t *dlsch_buffer = dl_info->rx_ind->rx_indication_body[pdu_id].pdsch_pdu.pdu;
-  uint8_t is_Msg3 = 1;
-  frame_t frame_tx = 0;
-  int slot_tx = 0;
-  int ret = 0;
   NR_RA_HEADER_RAPID *rarh = (NR_RA_HEADER_RAPID *) dlsch_buffer; // RAR subheader pointer
   NR_MAC_RAR *rar = (NR_MAC_RAR *) (dlsch_buffer + 1);   // RAR subPDU pointer
   uint8_t preamble_index = ra->ra_PreambleIndex;
@@ -3900,7 +4029,8 @@ static void nr_ue_process_rar(NR_UE_MAC_INST_t *mac, nr_downlink_indication_t *d
   T(T_NRUE_MAC_DL_RAR_PDU_WITH_DATA, T_INT(rnti), T_INT(frame), T_INT(slot),
     T_BUFFER(dlsch_buffer, dl_info->rx_ind->rx_indication_body[pdu_id].pdsch_pdu.pdu_length));
 
-  LOG_D(NR_MAC, "[%d.%d]: [UE %d][RAPROC] invoking MAC for received RAR (current preamble %d)\n", frame, slot, mac->ue_id, preamble_index);
+  ra->RA_backoff_limit = 0;
+  LOG_D(NR_MAC, "[%d.%d]: [UE %d][RAPROC] MAC received RAR (current preamble %d)\n", frame, slot, mac->ue_id, preamble_index);
 
   while (1) {
     n_subheaders++;
@@ -3908,10 +4038,11 @@ static void nr_ue_process_rar(NR_UE_MAC_INST_t *mac, nr_downlink_indication_t *d
       n_subPDUs++;
       LOG_I(NR_MAC, "[UE %d][RAPROC][RA-RNTI %04x] Got RAPID RAR subPDU\n", mac->ue_id, rnti);
     } else {
-      ra->RA_backoff_indicator = get_backoff_indicator(((NR_RA_HEADER_BI *)rarh)->BI);
-      ra->RA_BI_found = 1;
-      LOG_I(NR_MAC, "[UE %d][RAPROC][RA-RNTI %04x] Got BI RAR subPDU %d ms\n", mac->ue_id, ra->RA_backoff_indicator, rnti);
-      if ( ((NR_RA_HEADER_BI *)rarh)->E == 1) {
+      int bi_ms = table_7_2_1[((NR_RA_HEADER_BI *)rarh)->BI] * ra->scaling_factor_bi;
+      int slots_per_ms = mac->frame_structure.numb_slots_frame / 10;
+      ra->RA_backoff_limit = bi_ms * slots_per_ms;
+      LOG_I(NR_MAC, "[UE %d][RAPROC][RA-RNTI %04x] Got BI RAR subPDU %d ms\n", mac->ue_id, rnti, bi_ms);
+      if (((NR_RA_HEADER_BI *)rarh)->E == 1) {
         rarh += sizeof(NR_RA_HEADER_BI);
         continue;
       } else {
@@ -3919,9 +4050,15 @@ static void nr_ue_process_rar(NR_UE_MAC_INST_t *mac, nr_downlink_indication_t *d
       }
     }
     if (rarh->RAPID == preamble_index) {
+      // The MAC entity may stop ra-ResponseWindow (and hence monitoring for Random Access Response(s)) after
+      // successful reception of a Random Access Response containing Random Access Preamble identifiers
+      // that matches the transmitted PREAMBLE_INDEX.
+      nr_timer_stop(&ra->response_window_timer);
       LOG_A(NR_MAC, "[UE %d][RAPROC][%d.%d] Found RAR with the intended RAPID %d\n", mac->ue_id, frame, slot, rarh->RAPID);
       rar = (NR_MAC_RAR *) (dlsch_buffer + n_subheaders + (n_subPDUs - 1) * sizeof(NR_MAC_RAR));
-      ra->RA_RAPID_found = 1;
+      handle_rar_reception(mac, dl_info, rar, frame, slot);
+      if (ra->cfra)
+        nr_ra_succeeded(mac, dl_info->gNB_index, frame, slot);
       if (get_softmodem_params()->emulate_l1) {
         /* When we are emulating L1 with multiple UEs, the rx_indication will have
            multiple RAR PDUs. The code would previously handle each of these PDUs,
@@ -3971,142 +4108,6 @@ static void nr_ue_process_rar(NR_UE_MAC_INST_t *mac, nr_downlink_indication_t *d
         rarh->RAPID,
         preamble_index);
 #endif
-
-  if (ra->RA_RAPID_found) {
-    RAR_grant_t rar_grant;
-
-#ifdef DEBUG_RAR
-    // CSI
-    unsigned char csi_req = (unsigned char) (rar->UL_GRANT_4 & 0x01);
-#endif
-
-    // TPC
-    unsigned char tpc_command = (unsigned char) ((rar->UL_GRANT_4 >> 1) & 0x07);
-    switch (tpc_command){
-      case 0:
-        ra->Msg3_TPC = -6;
-        break;
-      case 1:
-        ra->Msg3_TPC = -4;
-        break;
-      case 2:
-        ra->Msg3_TPC = -2;
-        break;
-      case 3:
-        ra->Msg3_TPC = 0;
-        break;
-      case 4:
-        ra->Msg3_TPC = 2;
-        break;
-      case 5:
-        ra->Msg3_TPC = 4;
-        break;
-      case 6:
-        ra->Msg3_TPC = 6;
-        break;
-      case 7:
-        ra->Msg3_TPC = 8;
-        break;
-      default:
-        LOG_E(NR_PHY, "RAR impossible msg3 TPC\n");
-    }
-    // MCS
-    rar_grant.mcs = (unsigned char) (rar->UL_GRANT_4 >> 4);
-    // time alloc
-    rar_grant.Msg3_t_alloc = (unsigned char) (rar->UL_GRANT_3 & 0x0f);
-    // frequency alloc
-    rar_grant.Msg3_f_alloc = (uint16_t) ((rar->UL_GRANT_3 >> 4) | (rar->UL_GRANT_2 << 4) | ((rar->UL_GRANT_1 & 0x03) << 12));
-    // frequency hopping
-    rar_grant.freq_hopping = (unsigned char) (rar->UL_GRANT_1 >> 2);
-
-    // Schedule Msg3
-    const NR_UE_UL_BWP_t *current_UL_BWP = mac->current_UL_BWP;
-    const NR_UE_DL_BWP_t *current_DL_BWP = mac->current_DL_BWP;
-    const NR_BWP_PDCCH_t *pdcch_config = &mac->config_BWP_PDCCH[current_DL_BWP->bwp_id];
-    NR_tda_info_t tda_info = get_ul_tda_info(current_UL_BWP,
-                                             *pdcch_config->ra_SS->controlResourceSetId,
-                                             pdcch_config->ra_SS->searchSpaceType->present,
-                                             TYPE_RA_RNTI_,
-                                             rar_grant.Msg3_t_alloc);
-    if (!tda_info.valid_tda || tda_info.nrOfSymbols == 0) {
-      LOG_E(MAC, "Cannot schedule Msg3. Something wrong in TDA information\n");
-      return;
-    }
-    const int ntn_ue_koffset = GET_NTN_UE_K_OFFSET(&mac->ntn_ta, mac->current_UL_BWP->scs);
-    ret = nr_ue_pusch_scheduler(mac, is_Msg3, frame, slot, &frame_tx, &slot_tx, tda_info.k2 + ntn_ue_koffset);
-
-    // TA command
-    // if the timeAlignmentTimer associated with this TAG is not running
-    if (!nr_timer_is_active(&mac->time_alignment_timer)) {
-      const int ta = rar->TA2 + (rar->TA1 << 5);
-      set_time_alignment(mac, ta, rar_ta, frame_tx, slot_tx);
-      LOG_W(MAC, "received TA command %d\n", 31 + ta);
-    }
-    // else ignore the received Timing Advance Command
-
-#ifdef DEBUG_RAR
-    LOG_I(NR_MAC, "rarh->E = 0x%x\n", rarh->E);
-    LOG_I(NR_MAC, "rarh->T = 0x%x\n", rarh->T);
-    LOG_I(NR_MAC, "rarh->RAPID = 0x%x (%i)\n", rarh->RAPID, rarh->RAPID);
-
-    LOG_I(NR_MAC, "rar->R = 0x%x\n", rar->R);
-    LOG_I(NR_MAC, "rar->TA1 = 0x%x\n", rar->TA1);
-
-    LOG_I(NR_MAC, "rar->TA2 = 0x%x\n", rar->TA2);
-    LOG_I(NR_MAC, "rar->UL_GRANT_1 = 0x%x\n", rar->UL_GRANT_1);
-
-    LOG_I(NR_MAC, "rar->UL_GRANT_2 = 0x%x\n", rar->UL_GRANT_2);
-    LOG_I(NR_MAC, "rar->UL_GRANT_3 = 0x%x\n", rar->UL_GRANT_3);
-    LOG_I(NR_MAC, "rar->UL_GRANT_4 = 0x%x\n", rar->UL_GRANT_4);
-
-    LOG_I(NR_MAC, "rar->TCRNTI_1 = 0x%x\n", rar->TCRNTI_1);
-    LOG_I(NR_MAC, "rar->TCRNTI_2 = 0x%x\n", rar->TCRNTI_2);
-
-    LOG_I(NR_MAC, "[%d.%d]: [UE %d] Received RAR with t_alloc %d f_alloc %d ta_command %d mcs %d freq_hopping %d tpc_command %d\n",
-          frame,
-          slot,
-          mac->ue_id,
-          rar_grant.Msg3_t_alloc,
-          rar_grant.Msg3_f_alloc,
-          ta_command,
-          rar_grant.mcs,
-          rar_grant.freq_hopping,
-          tpc_command);
-#endif
-
-    if (ret != -1) {
-      uint16_t rnti = mac->crnti;
-      // Upon successful reception, set the T-CRNTI to the RAR value if the RA preamble is selected among the contention-based RA Preambles
-      if (!ra->cfra) {
-        ra->t_crnti = rar->TCRNTI_2 + (rar->TCRNTI_1 << 8);
-        rnti = ra->t_crnti;
-        if (!ra->msg3_C_RNTI)
-          nr_mac_rrc_msg3_ind(mac->ue_id, rnti, dl_info->gNB_index);
-      }
-      fapi_nr_ul_config_request_pdu_t *pdu = lockGet_ul_config(mac, frame_tx, slot_tx, FAPI_NR_UL_CONFIG_TYPE_PUSCH);
-      if (!pdu)
-        return;
-      // Config Msg3 PDU
-      int ret = nr_config_pusch_pdu(mac,
-                                    &tda_info,
-                                    &pdu->pusch_config_pdu,
-                                    NULL,
-                                    NULL,
-                                    &rar_grant,
-                                    rnti,
-                                    NR_SearchSpace__searchSpaceType_PR_common,
-                                    NR_DCI_NONE);
-      if (ret != 0)
-        remove_ul_config_last_item(pdu);
-      release_ul_config(pdu, false);
-    }
-
-  } else {
-    ra->t_crnti = 0;
-    // TODO if the Random Access Preamble was not selected by the MAC entity
-    //      among the contention-based Random Access Preamble
-    //      apply the Timing Advance Command and start or restart the timeAlignmentTimer
-  }
   return;
 }
 
diff --git a/openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c b/openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c
index d4d4aa3a4d..a5f129e312 100644
--- a/openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c
+++ b/openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c
@@ -236,6 +236,15 @@ void update_mac_timers(NR_UE_MAC_INST_t *mac)
       phr_info->phr_reporting |= (1 << phr_cause_periodic_timer);
     }
   }
+  bool ra_window_expired = nr_timer_tick(&mac->ra.response_window_timer);
+  if (ra_window_expired) // consider the Random Access Response reception not successful
+    nr_rar_not_successful(mac);
+  bool ra_backoff_expired = nr_timer_tick(&mac->ra.RA_backoff_timer);
+  if (ra_backoff_expired) {
+    // perform the Random Access Resource selection procedure after the backoff time
+    mac->ra.ra_state = nrRA_GENERATE_PREAMBLE;
+    ra_resource_selection(mac);
+  }
 }
 
 void remove_ul_config_last_item(fapi_nr_ul_config_request_pdu_t *pdu)
@@ -2064,7 +2073,6 @@ static bool is_prach_frame(frame_t frame, prach_occasion_info_t *prach_occasion_
 static void nr_ue_prach_scheduler(NR_UE_MAC_INST_t *mac, frame_t frameP, slot_t slotP)
 {
   RA_config_t *ra = &mac->ra;
-  ra->RA_offset = 2; // to compensate the rx frame offset at the gNB
   if (ra->ra_state != nrRA_GENERATE_PREAMBLE)
     return;
 
@@ -2076,7 +2084,6 @@ static void nr_ue_prach_scheduler(NR_UE_MAC_INST_t *mac, frame_t frameP, slot_t
 
   if (is_ul_slot(slotP, &mac->frame_structure)) {
     if (slotP == prach_occasion_info->slot) {
-      nr_get_RA_window(mac);
       fapi_nr_ul_config_request_pdu_t *pdu = lockGet_ul_config(mac, frameP, slotP, FAPI_NR_UL_CONFIG_TYPE_PRACH);
       if (!pdu) {
         LOG_E(NR_MAC, "Error in PRACH allocation\n");
@@ -2156,6 +2163,7 @@ static void nr_ue_prach_scheduler(NR_UE_MAC_INST_t *mac, frame_t frameP, slot_t
 
       if (ra->ra_type == RA_4_STEP) {
         ra->ra_state = nrRA_WAIT_RAR;
+        ra->start_response_window = true;
       } else if (ra->ra_type == RA_2_STEP) {
         NR_MsgA_PUSCH_Resource_r16_t *msgA_PUSCH_Resource =
             mac->current_UL_BWP->msgA_ConfigCommon_r16->msgA_PUSCH_Config_r16->msgA_PUSCH_ResourceGroupA_r16;
diff --git a/openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_power_procedures.cpp b/openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_power_procedures.cpp
index bcbec989c2..7dc0b43ec3 100644
--- a/openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_power_procedures.cpp
+++ b/openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_power_procedures.cpp
@@ -192,8 +192,6 @@ TEST(pusch_power_control, pusch_power_control_msg3)
   current_UL_BWP.BWPSize = 106;
   current_UL_BWP.channel_bandwidth = 40;
   mac.current_UL_BWP = &current_UL_BWP;
-  NR_RACH_ConfigCommon_t nr_rach_ConfigCommon = {0};
-  current_UL_BWP.rach_ConfigCommon = &nr_rach_ConfigCommon;
   mac.nr_band = 78;
   NR_PUSCH_Config_t pusch_Config = {0};
   current_UL_BWP.pusch_Config = &pusch_Config;
@@ -229,8 +227,8 @@ TEST(pusch_power_control, pusch_power_control_msg3)
                             num_rb,
                             start_prb);
 
-  long preambleReceivedTargetPower = -96;
-  nr_rach_ConfigCommon.rach_ConfigGeneric.preambleReceivedTargetPower = preambleReceivedTargetPower;
+  int preambleReceivedTargetPower = -96;
+  mac.ra.prach_resources.ra_preamble_rx_target_power = preambleReceivedTargetPower;
 
   int power = get_pusch_tx_power_ue(&mac,
                                     num_rb,
@@ -247,7 +245,7 @@ TEST(pusch_power_control, pusch_power_control_msg3)
                                     false);
   EXPECT_EQ(power, -84);
   EXPECT_LT(power, P_CMAX);
-  nr_rach_ConfigCommon.rach_ConfigGeneric.preambleReceivedTargetPower -= 2;
+  mac.ra.prach_resources.ra_preamble_rx_target_power -= 2;
 
   int reduced_power = get_pusch_tx_power_ue(&mac,
                                             num_rb,
@@ -372,8 +370,6 @@ TEST(pusch_power_control, pusch_power_control_state_initialization)
   current_UL_BWP.BWPSize = 106;
   current_UL_BWP.channel_bandwidth = 40;
   mac.current_UL_BWP = &current_UL_BWP;
-  NR_RACH_ConfigCommon_t nr_rach_ConfigCommon = {0};
-  current_UL_BWP.rach_ConfigCommon = &nr_rach_ConfigCommon;
   mac.nr_band = 78;
   NR_PUSCH_Config_t pusch_Config = {0};
   current_UL_BWP.pusch_Config = &pusch_Config;
@@ -393,8 +389,8 @@ TEST(pusch_power_control, pusch_power_control_state_initialization)
   uint32_t sum_bits_in_codeblocks = 56;
   int delta_pusch = 0;
   bool is_rar_tx_retx = true;
-  long preambleReceivedTargetPower = -96;
-  nr_rach_ConfigCommon.rach_ConfigGeneric.preambleReceivedTargetPower = preambleReceivedTargetPower;
+  int preambleReceivedTargetPower = -96;
+  mac.ra.prach_resources.ra_preamble_rx_target_power = preambleReceivedTargetPower;
 
   get_pusch_tx_power_ue(&mac,
                         num_rb,
diff --git a/openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_ra_procedures.cpp b/openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_ra_procedures.cpp
index 6e8916f6f0..504abae957 100644
--- a/openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_ra_procedures.cpp
+++ b/openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_ra_procedures.cpp
@@ -101,6 +101,7 @@ TEST(test_init_ra, four_step_cbra)
   mac.p_Max = 23;
   mac.nr_band = 78;
   mac.frame_structure.frame_type = TDD;
+  mac.frame_structure.numb_slots_frame = 20;
   mac.frequency_range = FR1;
   mac.first_sync_frame = 0;
   int frame = 151;
@@ -135,6 +136,7 @@ TEST(test_init_ra, four_step_cfra)
   mac.p_Max = 23;
   mac.nr_band = 78;
   mac.frame_structure.frame_type = TDD;
+  mac.frame_structure.numb_slots_frame = 20;
   mac.frequency_range = FR1;
   mac.first_sync_frame = 0;
   int frame = 151;
diff --git a/openair2/NR_UE_PHY_INTERFACE/NR_IF_Module.c b/openair2/NR_UE_PHY_INTERFACE/NR_IF_Module.c
index 9e7310cf40..d3e7a5a9aa 100644
--- a/openair2/NR_UE_PHY_INTERFACE/NR_IF_Module.c
+++ b/openair2/NR_UE_PHY_INTERFACE/NR_IF_Module.c
@@ -390,8 +390,7 @@ static bool is_my_dci(NR_UE_MAC_INST_t *mac, nfapi_nr_dl_dci_pdu_t *received_pdu
      already. Only once the RA procedure succeeds is the CRNTI value updated
      to the TC_RNTI. */
   if (get_softmodem_params()->nsa) {
-    if (received_pdu->RNTI != mac->crnti &&
-        (received_pdu->RNTI != mac->ra.ra_rnti || mac->ra.RA_RAPID_found))
+    if (received_pdu->RNTI != mac->crnti && (received_pdu->RNTI != mac->ra.ra_rnti))
       return false;
   }
   if (IS_SA_MODE(get_softmodem_params())) {
@@ -1292,11 +1291,11 @@ static uint32_t nr_ue_dl_processing(NR_UE_MAC_INST_t *mac, nr_downlink_indicatio
           ret_mask |= (handle_dlsch(mac, dl_info, i)) << FAPI_NR_RX_PDU_TYPE_DLSCH;
           break;
         case FAPI_NR_RX_PDU_TYPE_RAR:
-          ret_mask |= (handle_dlsch(mac, dl_info, i)) << FAPI_NR_RX_PDU_TYPE_RAR;
           if (!dl_info->rx_ind->rx_indication_body[i].pdsch_pdu.ack_nack)
             LOG_W(PHY, "Received a RAR-Msg2 but LDPC decode failed\n");
           else
             LOG_I(PHY, "RAR-Msg2 decoded\n");
+          ret_mask |= (handle_dlsch(mac, dl_info, i)) << FAPI_NR_RX_PDU_TYPE_RAR;
           break;
         case FAPI_NR_CSIRS_IND:
           ret_mask |= (handle_csirs_measurements(mac,