diff --git a/executables/nr-ru.c b/executables/nr-ru.c
index d6f7fb4374..b2c6e94acf 100644
--- a/executables/nr-ru.c
+++ b/executables/nr-ru.c
@@ -118,6 +118,7 @@ uint16_t sl_ahead;
 
 extern int emulate_rf;
 extern int numerology;
+extern int usrp_tx_thread;
 
 /*************************************************************/
 /* Functions to attach and configure RRU                     */
@@ -1510,12 +1511,14 @@ void *ru_thread( void *param ) {
     if ((ru->is_slave) && (ru->if_south == LOCAL_RF)) do_ru_synch(ru);
 
     // start trx write thread
-    if (ru->start_write_thread){
-      if(ru->start_write_thread(ru) != 0){
-        LOG_E(HW,"Could not start tx write thread\n");
-      }
-      else{
-        LOG_I(PHY,"tx write thread ready\n");
+    if(usrp_tx_thread == 1){
+      if (ru->start_write_thread){
+        if(ru->start_write_thread(ru) != 0){
+          LOG_E(HW,"Could not start tx write thread\n");
+        }
+        else{
+          LOG_I(PHY,"tx write thread ready\n");
+        }
       }
     }
   }
diff --git a/executables/nr-softmodem-common.h b/executables/nr-softmodem-common.h
index 305e4c4fc8..c968fee7b6 100644
--- a/executables/nr-softmodem-common.h
+++ b/executables/nr-softmodem-common.h
@@ -90,6 +90,7 @@
 #define CONFIG_HLP_EMULATE_RF    "Emulated RF enabled(disable by defult)\n"
 #define CONFIG_HLP_PARALLEL_CMD  "three config for level of parallelism 'PARALLEL_SINGLE_THREAD', 'PARALLEL_RU_L1_SPLIT', or 'PARALLEL_RU_L1_TRX_SPLIT'\n"
 #define CONFIG_HLP_WORKER_CMD    "two option for worker 'WORKER_DISABLE' or 'WORKER_ENABLE'\n"
+#define CONFIG_HLP_USRP_THREAD   "having extra thead for usrp tx\n"
 #define CONFIG_HLP_DISABLNBIOT   "disable nb-iot, even if defined in config\n"
 
 #define CONFIG_HLP_USRP_ARGS     "set the arguments to identify USRP (same syntax as in UHD)\n"
@@ -144,6 +145,10 @@ extern int sync_var;
 extern int transmission_mode;
 extern double cpuf;
 
+extern int emulate_rf;
+extern int numerology;
+extern int usrp_tx_thread;
+
 extern volatile int start_eNB;
 extern volatile int start_UE;
 
diff --git a/executables/nr-softmodem.c b/executables/nr-softmodem.c
index 2a9b3a0700..bf77125975 100644
--- a/executables/nr-softmodem.c
+++ b/executables/nr-softmodem.c
@@ -183,6 +183,7 @@ extern void *udp_eNB_task(void *args_p);
 int transmission_mode=1;
 int emulate_rf = 0;
 int numerology = 0;
+int usrp_tx_thread = 0;
 
 
 static char *parallel_config = NULL;
diff --git a/executables/nr-softmodem.h b/executables/nr-softmodem.h
index 27e3ba1e3e..d113ae45aa 100644
--- a/executables/nr-softmodem.h
+++ b/executables/nr-softmodem.h
@@ -34,6 +34,7 @@
     {"emulate-rf" ,           CONFIG_HLP_EMULATE_RF,  PARAMFLAG_BOOL,   iptr:&emulate_rf,                   defintval:0,                   TYPE_INT,    0},        \
     {"parallel-config",       CONFIG_HLP_PARALLEL_CMD,0,                strptr:(char **)&parallel_config,   defstrval:NULL,                TYPE_STRING, 0},        \
     {"worker-config",         CONFIG_HLP_WORKER_CMD,  0,                strptr:(char **)&worker_config,     defstrval:NULL,                TYPE_STRING, 0},        \
+    {"usrp-tx-thread-config", CONFIG_HLP_USRP_THREAD, 0,                iptr:&usrp_tx_thread,               defstrval:0,                   TYPE_INT,    0},        \
     {"s" ,                    CONFIG_HLP_SNR,         0,                dblptr:&snr_dB,                     defdblval:25,                  TYPE_DOUBLE, 0},        \
   }
 
diff --git a/executables/nr-uesoftmodem.c b/executables/nr-uesoftmodem.c
index 5d3edbfcb1..dd881c409b 100644
--- a/executables/nr-uesoftmodem.c
+++ b/executables/nr-uesoftmodem.c
@@ -173,6 +173,7 @@ uint64_t num_missed_slots=0; // counter for the number of missed slots
 
 int transmission_mode=1;
 int numerology = 0;
+int usrp_tx_thread = 0;
 
 /* flag set by eNB conf file to specify if the radio head is local or remote (default option is local) */
 //uint8_t local_remote_radio = BBU_LOCAL_RADIO_HEAD;
diff --git a/openair1/PHY/LTE_TRANSPORT/dlsch_coding.c b/openair1/PHY/LTE_TRANSPORT/dlsch_coding.c
index 15eb5206a1..14036ad43a 100644
--- a/openair1/PHY/LTE_TRANSPORT/dlsch_coding.c
+++ b/openair1/PHY/LTE_TRANSPORT/dlsch_coding.c
@@ -422,6 +422,6 @@ int dlsch_encoding(PHY_VARS_eNB *eNB,
     else
       r_offset += Nl*Qm * ((GpmodC==0?0:1) + (Gp/C));
   }
-
+  VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_ENB_DLSCH_ENCODING, VCD_FUNCTION_OUT);
   return(0);
 }
diff --git a/targets/ARCH/BLADERF/USERSPACE/LIB/bladerf_lib.c b/targets/ARCH/BLADERF/USERSPACE/LIB/bladerf_lib.c
index c4e593ca92..af5ab5ad6d 100644
--- a/targets/ARCH/BLADERF/USERSPACE/LIB/bladerf_lib.c
+++ b/targets/ARCH/BLADERF/USERSPACE/LIB/bladerf_lib.c
@@ -330,7 +330,10 @@ int trx_brf_set_gains(openair0_device* device,
 {
     return(0);
 }
-
+int trx_brf_write_init(openair0_device *device)
+{
+    return 0;
+}
 
 #define RXDCLENGTH 16384
 int16_t cos_fsover8[8]  = {2047,   1447,      0,  -1448,  -2047,  -1448,     0,   1447};
@@ -1145,6 +1148,7 @@ int device_init(openair0_device *device,
     device->trx_stop_func        = trx_brf_stop;
     device->trx_set_freq_func    = trx_brf_set_freq;
     device->trx_set_gains_func   = trx_brf_set_gains;
+    device->trx_write_init       = trx_brf_write_init;
     device->openair0_cfg = openair0_cfg;
     device->priv = (void *)brf;
 
diff --git a/targets/ARCH/ETHERNET/USERSPACE/LIB/ethernet_lib.c b/targets/ARCH/ETHERNET/USERSPACE/LIB/ethernet_lib.c
index c5822a3650..c72e7d4130 100644
--- a/targets/ARCH/ETHERNET/USERSPACE/LIB/ethernet_lib.c
+++ b/targets/ARCH/ETHERNET/USERSPACE/LIB/ethernet_lib.c
@@ -197,6 +197,10 @@ int trx_eth_reset_stats(openair0_device* device)
     return(0);
 }
 
+int trx_eth_write_init(openair0_device *device)
+{
+    return 0;
+}
 
 int ethernet_tune(openair0_device *device,
                   unsigned int option,
@@ -415,8 +419,9 @@ int transport_init(openair0_device *device,
     device->trx_reset_stats_func = trx_eth_reset_stats;
     device->trx_end_func         = trx_eth_end;
     device->trx_stop_func        = trx_eth_stop;
-    device->trx_set_freq_func = trx_eth_set_freq;
-    device->trx_set_gains_func = trx_eth_set_gains;
+    device->trx_set_freq_func    = trx_eth_set_freq;
+    device->trx_set_gains_func   = trx_eth_set_gains;
+    device->trx_write_init       = trx_eth_write_init;
 
     if (eth->flags == ETH_RAW_MODE) {
         device->trx_write_func   = trx_eth_write_raw;
diff --git a/targets/ARCH/IRIS/USERSPACE/LIB/iris_lib.cpp b/targets/ARCH/IRIS/USERSPACE/LIB/iris_lib.cpp
index 5b20d8a8c7..1273097f3b 100644
--- a/targets/ARCH/IRIS/USERSPACE/LIB/iris_lib.cpp
+++ b/targets/ARCH/IRIS/USERSPACE/LIB/iris_lib.cpp
@@ -510,6 +510,11 @@ int trx_iris_reset_stats(openair0_device *device) {
 
 }
 
+int trx_iris_write_init(openair0_device *device)
+{
+    return 0;
+}
+
 
 extern "C" {
 /*! \brief Initialize Openair Iris target. It returns 0 if OK
@@ -831,6 +836,7 @@ int device_init(openair0_device *device, openair0_config_t *openair0_cfg) {
     device->trx_set_freq_func = trx_iris_set_freq;
     device->trx_set_gains_func = trx_iris_set_gains;
     device->openair0_cfg = openair0_cfg;
+    device->trx_write_init = trx_iris_write_init;
 
     s->sample_rate = openair0_cfg[0].sample_rate;
     // TODO:
diff --git a/targets/ARCH/LMSSDR/USERSPACE/LIB/lms_lib.cpp b/targets/ARCH/LMSSDR/USERSPACE/LIB/lms_lib.cpp
index 9fcfbdf571..79a389bfeb 100644
--- a/targets/ARCH/LMSSDR/USERSPACE/LIB/lms_lib.cpp
+++ b/targets/ARCH/LMSSDR/USERSPACE/LIB/lms_lib.cpp
@@ -350,6 +350,10 @@ void trx_lms_end(openair0_device *device) {
 
 }
 
+int trx_lms_write_init(openair0_device *device)
+{
+    return 0;
+}
 extern "C" {
 /*! \brief Initialize Openair LMSSDR target. It returns 0 if OK
 * \param device the hardware to use
@@ -406,6 +410,7 @@ int device_init(openair0_device *device, openair0_config_t *openair0_cfg){
   device->trx_stop_func = trx_lms_stop;
   device->trx_set_freq_func = trx_lms_set_freq;
   device->trx_set_gains_func = trx_lms_set_gains;
+  device->trx_write_init = trx_lms_write_init;
 
   device->openair0_cfg = openair0_cfg;
 
diff --git a/targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp b/targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp
index 08f0cd720b..62f77699a4 100644
--- a/targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp
+++ b/targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp
@@ -70,6 +70,8 @@
  * @{
  */
 
+extern int usrp_tx_thread;
+
 
 typedef struct {
 
@@ -345,7 +347,6 @@ static int trx_usrp_write(openair0_device *device,
   int flags_msb = (flags>>8)&0xff;
 
   int end;
-  int write_tread = 0;
   openair0_thread_t *write_thread = &device->write_thread;
   openair0_write_package_t *write_package = write_thread->write_package;
 
@@ -382,7 +383,7 @@ static int trx_usrp_write(openair0_device *device,
      last_packet_state  = true;
     }
 
-  if(write_tread == 0){
+  if(usrp_tx_thread == 0){
 #if defined(__x86_64) || defined(__i386__)
   #ifdef __AVX2__
       nsamps2 = (nsamps+7)>>3;
@@ -586,7 +587,7 @@ void *trx_usrp_write_thread(void * arg){
   return NULL;
 }
 
-int trx_write_init(openair0_device *device){
+int trx_usrp_write_init(openair0_device *device){
 
   uhd::set_thread_priority_safe(1.0);
   openair0_thread_t *write_thread = &device->write_thread;
@@ -932,7 +933,7 @@ extern "C" {
     device->trx_stop_func  = trx_usrp_stop;
     device->trx_set_freq_func = trx_usrp_set_freq;
     device->trx_set_gains_func   = trx_usrp_set_gains;
-    device->trx_write_init = trx_write_init;
+    device->trx_write_init = trx_usrp_write_init;
 
 
     // hotfix! to be checked later
diff --git a/targets/ARCH/tcp_bridge/tcp_bridge.c b/targets/ARCH/tcp_bridge/tcp_bridge.c
index 8b287acfa1..f8c12dcb7a 100644
--- a/targets/ARCH/tcp_bridge/tcp_bridge.c
+++ b/targets/ARCH/tcp_bridge/tcp_bridge.c
@@ -243,6 +243,11 @@ ts += nsamps;
   return nsamps;
 }
 
+int tcp_bridge_write_init(openair0_device *device)
+{
+    return 0;
+}
+
 __attribute__((__visibility__("default")))
 int device_init(openair0_device* device, openair0_config_t *openair0_cfg)
 {
@@ -267,6 +272,7 @@ int device_init(openair0_device* device, openair0_config_t *openair0_cfg)
   device->trx_set_gains_func = tcp_bridge_set_gains;
   device->trx_write_func   = tcp_bridge_write;
   device->trx_read_func    = tcp_bridge_read;
+  device->trx_write_init   = tcp_bridge_write_init;
 
   device->priv = tcp_bridge;
 
diff --git a/targets/RT/USER/lte-ru.c b/targets/RT/USER/lte-ru.c
index d2e734f205..4d89020077 100644
--- a/targets/RT/USER/lte-ru.c
+++ b/targets/RT/USER/lte-ru.c
@@ -679,7 +679,11 @@ void rx_rf(RU_t *ru,
     resynch=1;
   }
 
-  proc->timestamp_rx = ts-ru->ts_offset;
+  if(get_softmodem_params()->emulate_rf) {
+    proc->timestamp_rx = old_ts + fp->samples_per_tti;
+  } else {
+    proc->timestamp_rx = ts-ru->ts_offset;
+  }
 
   //  AssertFatal(rxs == fp->samples_per_tti,
   //        "rx_rf: Asked for %d samples, got %d from SDR\n",fp->samples_per_tti,rxs);
@@ -2337,19 +2341,22 @@ void init_RU_proc(RU_t *ru) {
     LOG_I(PHY,"%s() DJP - added creation of pthread_prach\n", __FUNCTION__);
     pthread_create( &proc->pthread_prach, attr_prach, ru_thread_prach, (void *)ru );
     ru->state=RU_RUN;
-    fill_rf_config(ru,ru->rf_config_file);
-    init_frame_parms(ru->frame_parms,1);
-    ru->frame_parms->nb_antennas_rx = ru->nb_rx;
-    phy_init_RU(ru);
-    ret = openair0_device_load(&ru->rfdevice,&ru->openair0_cfg);
-    if (ret < 0) {
-       LOG_I(PHY,"Exiting, cannot load device. Make sure that your SDR board is connected!\n");
-       exit(1);
-    }
+    if(!get_softmodem_params()->emulate_rf)
+    {
+      fill_rf_config(ru,ru->rf_config_file);
+      init_frame_parms(ru->frame_parms,1);
+      ru->frame_parms->nb_antennas_rx = ru->nb_rx;
+      phy_init_RU(ru);
+      ret = openair0_device_load(&ru->rfdevice,&ru->openair0_cfg);
+      if (ret < 0) {
+         LOG_I(PHY,"Exiting, cannot load device. Make sure that your SDR board is connected!\n");
+         exit(1);
+      }
 
-    if (setup_RU_buffers(ru)!=0) {
-      LOG_I(PHY,"Exiting, cannot initialize RU Buffers\n");
-      exit(1);
+      if (setup_RU_buffers(ru)!=0) {
+        LOG_I(PHY,"Exiting, cannot initialize RU Buffers\n");
+        exit(1);
+      }
     }
   }
 
diff --git a/targets/RT/USER/lte-softmodem.c b/targets/RT/USER/lte-softmodem.c
index d8c5e25593..4715a4e995 100644
--- a/targets/RT/USER/lte-softmodem.c
+++ b/targets/RT/USER/lte-softmodem.c
@@ -170,6 +170,7 @@ extern void init_eNB_afterRU(void);
 int transmission_mode=1;
 int emulate_rf = 0;
 int numerology = 0;
+int usrp_tx_thread = 0;
 
 THREAD_STRUCT thread_struct;
 /* struct for ethernet specific parameters given in eNB conf file */
@@ -659,6 +660,7 @@ int main ( int argc, char **argv )
          initTpool("n", L1proc->threadPool, true);
       initNotifiedFIFO(L1proc->respEncode);
       initNotifiedFIFO(L1proc->respDecode);
+      RC.eNB[x][CC_id]->proc.L1_proc_tx.threadPool = L1proc->threadPool;
     }
 
 
diff --git a/targets/RT/USER/lte-softmodem.h b/targets/RT/USER/lte-softmodem.h
index c5fdb5f546..1c537dabe3 100644
--- a/targets/RT/USER/lte-softmodem.h
+++ b/targets/RT/USER/lte-softmodem.h
@@ -155,6 +155,10 @@ extern int sync_var;
 extern int transmission_mode;
 extern double cpuf;
 
+extern int emulate_rf;
+extern int numerology;
+extern int usrp_tx_thread;
+
 // In lte-enb.c
 extern void stop_eNB(int);
 extern void kill_eNB_proc(int inst);
diff --git a/targets/RT/USER/lte-uesoftmodem.c b/targets/RT/USER/lte-uesoftmodem.c
index 2c9271888b..a45ecd2298 100644
--- a/targets/RT/USER/lte-uesoftmodem.c
+++ b/targets/RT/USER/lte-uesoftmodem.c
@@ -171,6 +171,8 @@ extern void get_uethreads_params(void);
 
 int transmission_mode=1;
 
+int usrp_tx_thread = 0;
+
 
 char *usrp_args=NULL;
 char *usrp_clksrc=NULL;