CFO included in pbchsim

openair1/SIMULATION/NR_PHY/pbchsim.c

@@ -87,10 +87,12 @@ int main(int argc, char **argv)
 
   int i,l,aa;
   double sigma2, sigma2_dB=10,SNR,snr0=-2.0,snr1=2.0;
+  double cfo=0;
   uint8_t snr1set=0;
   int **txdata;
   double **s_re,**s_im,**r_re,**r_im;
   double iqim = 0.0;
+  double ip =0.0;
   unsigned char pbch_pdu[6];
   //  int sync_pos, sync_pos_slot;
   //  FILE *rx_frame_file;
@@ -118,7 +120,7 @@ int main(int argc, char **argv)
 
   double pbch_sinr;
   int pbch_tx_ant;
-  int N_RB_DL=273,mu=1;
+  int N_RB_DL=106,mu=1;
 
   unsigned char frame_type = 0;
   unsigned char pbch_phase = 0;
@@ -144,7 +146,7 @@ int main(int argc, char **argv)
 
   randominit(0);
 
-  while ((c = getopt (argc, argv, "f:hA:pf:g:i:j:n:s:S:t:x:y:z:N:F:GR:dP:IL:")) != -1) {
+  while ((c = getopt (argc, argv, "f:hA:pf:g:i:j:n:o:s:S:t:x:y:z:N:F:GR:dP:IL:")) != -1) {
     switch (c) {
     case 'f':
       write_output_file=1;
@@ -210,6 +212,11 @@ int main(int argc, char **argv)
       n_trials = atoi(optarg);
       break;
 
+    case 'o':
+      cfo = atof(optarg);
+      msg("Setting CFO to %f Hz\n",cfo);
+      break;
+
     case 's':
       snr0 = atof(optarg);
       msg("Setting SNR0 to %f\n",snr0);
@@ -323,6 +330,7 @@ int main(int argc, char **argv)
       printf("-z Number of RX antennas used in UE\n");
       printf("-i Relative strength of first intefering eNB (in dB) - cell_id mod 3 = 1\n");
       printf("-j Relative strength of second intefering eNB (in dB) - cell_id mod 3 = 2\n");
+      printf("-o Carrier frequency offset in Hz\n");
       printf("-N Nid_cell\n");
       printf("-R N_RB_DL\n");
       printf("-O oversampling factor (1,2,4,8,16)\n");
@@ -358,26 +366,43 @@ int main(int argc, char **argv)
   nr_phy_config_request_sim(gNB,N_RB_DL,N_RB_DL,mu);
   phy_init_nr_gNB(gNB,0,0);
 
-  double fs,bw;
+  double fs,bw,scs,eps;
 
   if (mu == 1 && N_RB_DL == 217) { 
     fs = 122.88e6;
     bw = 80e6;
+    scs = 30000;
   }					       
   else if (mu == 1 && N_RB_DL == 245) {
     fs = 122.88e6;
     bw = 90e6;
+    scs = 30000;
   }
   else if (mu == 1 && N_RB_DL == 273) {
     fs = 122.88e6;
     bw = 100e6;
+    scs = 30000;
   }
   else if (mu == 1 && N_RB_DL == 106) { 
     fs = 61.44e6;
     bw = 40e6;
+    scs = 30000;
   }
   else AssertFatal(1==0,"Unsupported numerology for mu %d, N_RB %d\n",mu, N_RB_DL);
 
+  // cfo with respect to sub-carrier spacing
+  eps = cfo/scs;
+  int IFO;
+
+  if(eps!=0.0){
+	printf("Introducing a CFO of %lf relative to SCS of %d kHz\n",eps,(int)(scs/1000));
+	if (eps>0)	
+  	  IFO=(int)(eps+0.5);
+	else
+	  IFO=(int)(eps-0.5);
+	printf("FFO = %lf; IFO = %d\n",eps-IFO,IFO);
+  }
+
   gNB2UE = new_channel_desc_scm(n_tx,
                                 n_rx,
                                 channel_model,
@@ -490,6 +515,7 @@ int main(int argc, char **argv)
 
   //  printf("txlev %d (%f)\n",txlev,10*log10(txlev));
 
+
   for (i=0; i<frame_length_complex_samples; i++) {
     for (aa=0; aa<frame_parms->nb_antennas_tx; aa++) {
       r_re[aa][i] = ((double)(((short *)txdata[aa]))[(i<<1)]);
@@ -511,7 +537,30 @@ int main(int argc, char **argv)
       sigma2_dB = 10*log10((double)txlev)-SNR;
       sigma2 = pow(10,sigma2_dB/10);
       //      printf("sigma2 %f (%f dB)\n",sigma2,sigma2_dB);
+ 
+      if(eps!=0.0)
+        rf_rx(r_re,  // real part of txdata
+           r_im,  // imag part of txdata
+           NULL,  // interference real part
+           NULL, // interference imag part
+           0,  // interference power
+           frame_parms->nb_antennas_rx,  // number of rx antennas
+           frame_length_complex_samples,  // number of samples in frame
+           1.0e7/frame_length_complex_samples,   //sampling time (ns)
+           cfo,	// frequency offset in Hz
+           0.0, // drift (not implemented)
+           0.0, // noise figure (not implemented)
+           0.0, // rx gain in dB ?
+           200, // 3rd order non-linearity in dB ?
+           &ip, // initial phase
+           30.0e3,  // phase noise cutoff in kHz
+           -500.0, // phase noise amplitude in dBc
+           0.0,  // IQ imbalance (dB),
+	   0.0); // IQ phase imbalance (rad)
 
+
+
+   
       for (i=0; i<frame_length_complex_samples; i++) {
 	for (aa=0; aa<frame_parms->nb_antennas_rx; aa++) {
 	  

openair1/SIMULATION/RF/rf.c

@@ -107,10 +107,10 @@ void rf_rx(double **r_re,
     exit(-1);
   }
 
-  if (fabs(f_off) > 10000.0) {
+/*  if (fabs(f_off) > 10000.0) {
     printf("rf.c: Illegal f_off %f\n",f_off);
     exit(-1);
-  }
+  }*/
 
   if (fabs(drift) > 1000.0) {
     printf("rf.c: Illegal drift %f\n",drift);