fix for tx_amp_backoff_dB = 0

openair1/PHY/INIT/nr_init.c

@@ -520,7 +520,7 @@ int phy_init_nr_gNB(PHY_VARS_gNB *gNB,
   AssertFatal(pdcch_dmrs!=NULL, "NR init: pdcch_dmrs malloc failed\n");
 
   gNB->bad_pucch = 0;
-
+  if (gNB->TX_AMP == 0) gNB->TX_AMP = AMP;
   // ceil(((NB_RB<<1)*3)/32) // 3 RE *2(QPSK)
   int pdcch_dmrs_init_length =  (((fp->N_RB_DL<<1)*3)>>5)+1;
 

openair1/PHY/MODULATION/nr_modulation.c

@@ -146,8 +146,9 @@ void nr_modulation(uint32_t *in,
   case 2:
     nr_mod_table128 = (__m128i*) nr_qpsk_byte_mod_table;
     out128 = (__m128i*) out;
-    for (i=0; i<length/8; i++)
+    for (i=0; i<length/8; i++) 
       out128[i] = nr_mod_table128[in_bytes[i]];
+
     // the bits that are left out
     i = i*8/2;
     nr_mod_table32 = (int32_t*) nr_qpsk_mod_table;

openair1/PHY/NR_REFSIG/nr_gen_mod_table.c

@@ -47,7 +47,7 @@ void nr_generate_modulation_table() {
   for (i=0; i<4; i++) {
     nr_qpsk_mod_table[i*2]   = (short)(1-2*(i&1))*val*sqrt2*sqrt2;
     nr_qpsk_mod_table[i*2+1] = (short)(1-2*((i>>1)&1))*val*sqrt2*sqrt2;
-    //printf("%d j%d\n",nr_qpsk_mod_table[i*2],nr_qpsk_mod_table[i*2+1]);
+    //printf("QPSK : %d j%d\n",nr_qpsk_mod_table[i*2],nr_qpsk_mod_table[i*2+1]);
   }
 
 #if defined(__SSE2__)
@@ -57,7 +57,6 @@ void nr_generate_modulation_table() {
     for (j=0; j<4; j++) {
       table[i*8+(j*2)]   = (short)(1-2*((i>>(j*2))&1))*val*sqrt2*sqrt2;
       table[i*8+(j*2)+1] = (short)(1-2*((i>>(j*2+1))&1))*val*sqrt2*sqrt2;
-      //printf("%d j%d\n",nr_qpsk_byte_mod_table[i*8+(j*2)],nr_qpsk_byte_mod_table[i*8+(j*2)+1]);
     }
   }
 #endif
@@ -68,7 +67,7 @@ void nr_generate_modulation_table() {
     for (j=0; j<2; j++) {
       table[i*4+(j*2)]   = (short)((1-2*((i>>(j*4))&1))*(2-(1-2*((i>>(j*4+2))&1))))*val*sqrt10*sqrt2;
       table[i*4+(j*2)+1] = (short)((1-2*((i>>(j*4+1))&1))*(2-(1-2*((i>>(j*4+3))&1))))*val*sqrt10*sqrt2;
-     //printf("%d j%d\n",nr_16qam_byte_mod_table[i*4+(j*2)],nr_16qam_byte_mod_table[i*4+(j*2)+1]);
+      //printf("%d j%d\n",nr_16qam_byte_mod_table[i*4+(j*2)],nr_16qam_byte_mod_table[i*4+(j*2)+1]);
     }
   }
 
@@ -76,7 +75,7 @@ void nr_generate_modulation_table() {
   for (i=0; i<16; i++) {
     table[i*2]   = (short)((1-2*(i&1))*(2-(1-2*((i>>2)&1))))*val*sqrt10*sqrt2;
     table[i*2+1] = (short)((1-2*((i>>1)&1))*(2-(1-2*((i>>3)&1))))*val*sqrt10*sqrt2;
-    //printf("%d j%d\n",table[i*2],table[i*2+1]);
+   // printf("%d j%d\n",table[i*2],table[i*2+1]);
   }
 
   //64QAM

openair1/PHY/NR_TRANSPORT/nr_dlsch.c

@@ -60,7 +60,7 @@ void nr_generate_pdsch(processingData_L1tx_t *msgTx,
   PHY_VARS_gNB *gNB = msgTx->gNB;
   NR_gNB_DLSCH_t *dlsch;
   int32_t** txdataF = gNB->common_vars.txdataF;
-  int16_t amp = AMP;
+  int16_t amp = gNB->TX_AMP;
   int xOverhead = 0;
   NR_DL_FRAME_PARMS *frame_parms = &gNB->frame_parms;
   time_stats_t *dlsch_encoding_stats=&gNB->dlsch_encoding_stats;

openair1/PHY/defs_gNB.h

@@ -765,6 +765,8 @@ typedef struct PHY_VARS_gNB_s {
   uint8_t pbch_configured;
   char gNB_generate_rar;
 
+  // reference amplitude for TX 
+  int16_t TX_AMP;
   // PUCCH0 Look-up table for cyclic-shifts
   NR_gNB_PUCCH0_LUT_t pucch0_lut;
 

openair2/GNB_APP/L1_nr_paramdef.h

@@ -52,6 +52,7 @@
 #define CONFIG_STRING_L1_PRACH_DTX_THRESHOLD               "prach_dtx_threshold"
 #define CONFIG_STRING_L1_PUSCH_DTX_THRESHOLD               "pusch_dtx_threshold"
 #define CONFIG_STRING_L1_MAX_LDPC_ITERATIONS               "max_ldpc_iterations"
+#define CONFIG_STRING_L1_TX_AMP_BACKOFF_dB                 "tx_amp_backoff_dB"
 /*----------------------------------------------------------------------------------------------------------------------------------------------------*/
 /*                                            L1 configuration parameters                                                                             */
 /*   optname                                         helpstr   paramflags    XXXptr              defXXXval                  type           numelt     */
@@ -72,6 +73,7 @@
 {CONFIG_STRING_L1_PRACH_DTX_THRESHOLD,               NULL,      0,         uptr:NULL,           defintval:150,             TYPE_UINT,     0},         \
 {CONFIG_STRING_L1_PUSCH_DTX_THRESHOLD,               NULL,      0,         uptr:NULL,           defintval:50,              TYPE_UINT,     0},         \
 {CONFIG_STRING_L1_MAX_LDPC_ITERATIONS,               NULL,      0,         uptr:NULL,           defintval:5,               TYPE_UINT,     0},          \
+{CONFIG_STRING_L1_TX_AMP_BACKOFF_dB,                 NULL,      0,         uptr:NULL,           defintval:36,               TYPE_UINT,     0},          \
 }
 #define L1_CC_IDX                                          0
 #define L1_TRANSPORT_N_PREFERENCE_IDX                      1
@@ -88,6 +90,7 @@
 #define L1_PRACH_DTX_THRESHOLD                             12
 #define L1_PUSCH_DTX_THRESHOLD                             13
 #define L1_MAX_LDPC_ITERATIONS                             14
+#define L1_TX_AMP_BACKOFF_dB                               15
 
 /*----------------------------------------------------------------------------------------------------------------------------------------------------*/
 #endif

openair2/GNB_APP/gnb_config.c

@@ -729,6 +729,9 @@ void RCconfig_NR_L1(void) {
       RC.gNB[j]->prach_thres        = *(L1_ParamList.paramarray[j][L1_PRACH_DTX_THRESHOLD].uptr);
       RC.gNB[j]->pusch_thres        = *(L1_ParamList.paramarray[j][L1_PUSCH_DTX_THRESHOLD].uptr);
       RC.gNB[j]->max_ldpc_iterations = *(L1_ParamList.paramarray[j][L1_MAX_LDPC_ITERATIONS].uptr);
+      RC.gNB[j]->TX_AMP             = (int16_t)(32767.0/pow(10.0,.05*(double)(*L1_ParamList.paramarray[j][L1_TX_AMP_BACKOFF_dB].uptr)));
+      LOG_I(PHY,"TX_AMP = %d (-%d dBFS)\n",RC.gNB[j]->TX_AMP,*L1_ParamList.paramarray[j][L1_TX_AMP_BACKOFF_dB].uptr);
+      AssertFatal(RC.gNB[j]->TX_AMP > 300,"TX_AMP is too small\n");
       RC.gNB[j]->num_ulprbbl        = num_prbbl;
       RC.gNB[j]->ap_N1              = N1;
       RC.gNB[j]->ap_N2              = N2;