fixed initialization of rotation for symbol 0

openair1/PHY/MODULATION/nr_modulation.c

@@ -411,8 +411,11 @@ void init_symbol_rotation(NR_DL_FRAME_PARMS *fp,uint64_t CarrierFreq) {
   double tl=0,poff,exp_re,exp_im;
   double Ncp,Ncpm1=Ncp0;
 
-  fp->symbol_rotation[0] = 32767;
-  fp->symbol_rotation[1] = 0;
+  poff = 2*M_PI*((Ncp0*Tc))*f0;
+  exp_re = cos(poff);
+  exp_im = sin(-poff);
+  fp->symbol_rotation[0]=(int16_t)floor(exp_re*32767);
+  fp->symbol_rotation[1]=(int16_t)floor(exp_im*32767);
   LOG_I(PHY,"Doing symbol rotation calculation for gNB TX/RX, f0 %f Hz, Nsymb %d\n",f0,nsymb);
   LOG_I(PHY,"Symbol rotation %d/%d => (%d,%d)\n",0,nsymb,fp->symbol_rotation[0],fp->symbol_rotation[1]);
   for (int l=1;l<nsymb;l++) {

openair1/PHY/MODULATION/slot_fep_nr.c

@@ -488,9 +488,9 @@ int nr_slot_fep_ul(NR_DL_FRAME_PARMS *frame_parms,
   rxdataF[symbol * frame_parms->ofdm_symbol_size] = 0;
 
   int symb_offset = (Ns%frame_parms->slots_per_subframe)*frame_parms->symbols_per_slot;
-  int32_t rot2 = ((uint32_t*)frame_parms->symbol_rotation)[symbol+symb_offset];
+  uint32_t rot2 = ((uint32_t*)frame_parms->symbol_rotation)[symbol+symb_offset];
   ((int16_t*)&rot2)[1]=-((int16_t*)&rot2)[1];
-  LOG_D(PHY,"slot %d, symb_offset %d rotating by %d.%d\n",slot,symbol_offset,((int16_t*)&rot2)[0],((int16_t*)&rot2)[1]);
+  LOG_D(PHY,"slot %d, symb_offset %d rotating by %d.%d\n",Ns,symb_offset,((int16_t*)&rot2)[0],((int16_t*)&rot2)[1]);
   rotate_cpx_vector((int16_t *)&rxdataF[frame_parms->ofdm_symbol_size*symbol],
 		    (int16_t*)&rot2,
 		    (int16_t *)&rxdataF[frame_parms->ofdm_symbol_size*symbol],

openair1/SIMULATION/NR_PHY/ulsim.c

@@ -926,13 +926,16 @@ int main(int argc, char **argv)
         start_meas(&gNB->phy_proc_rx);
         phy_procedures_gNB_common_RX(gNB, frame, slot);
 
+        phy_procedures_gNB_uespec_RX(gNB, frame, slot);
+
 	if (n_trials==1 && round==0) {
 	  LOG_M("rxsig0.m","rx0",&gNB->common_vars.rxdata[0][slot_offset],slot_length,1,1);
 
 	  LOG_M("rxsigF0.m","rxsF0",gNB->common_vars.rxdataF[0]+start_symbol*frame_parms->ofdm_symbol_size,nb_symb_sch*frame_parms->ofdm_symbol_size,1,1);
 
 	}
-        phy_procedures_gNB_uespec_RX(gNB, frame, slot);
+
+
 	if (n_trials == 1  && round==0) { 
 #ifdef __AVX2__
 	  int off = ((nb_rb&1) == 1)? 4:0;