Fix: interference power measurement on DRS.

openair1/PHY/LTE_TRANSPORT/ulsch_demodulation.c

@@ -1072,10 +1072,22 @@ void rx_ulsch(PHY_VARS_eNB *eNB,
   }
 
   for (i=0; i<frame_parms->nb_antennas_rx; i++) {
-    pusch_vars->ulsch_power[i] = signal_energy_nodc(pusch_vars->drs_ch_estimates[i],
-                                 ulsch[UE_id]->harq_processes[harq_pid]->nb_rb*12)/correction_factor;
-    LOG_D(PHY,"%4.4d.%d power harq_pid %d rb %2.2d TBS %2.2d (MPR_times_Ks %d correction %d)  power %d dBtimes10\n", proc->frame_rx, proc->subframe_rx, harq_pid,
-          ulsch[UE_id]->harq_processes[harq_pid]->nb_rb, ulsch[UE_id]->harq_processes[harq_pid]->TBS,MPR_times_100Ks,correction_factor,dB_fixed_times10(pusch_vars->ulsch_power[i]));
+    
+
+    pusch_vars->ulsch_interference_power[i] = interference_power(pusch_vars->drs_ch_estimates[i],ulsch[UE_id]->harq_processes[harq_pid]->nb_rb*12)/correction_factor;
+    pusch_vars->ulsch_power[i] = signal_power(pusch_vars->drs_ch_estimates[i],ulsch[UE_id]->harq_processes[harq_pid]->nb_rb*12)/correction_factor;
+
+    if(pusch_vars->ulsch_power[i]>0x20000000){
+      pusch_vars->ulsch_power[i] = 0x20000000;
+      pusch_vars->ulsch_interference_power[i] = 1;
+    }else{
+      pusch_vars->ulsch_power[i] -=  pusch_vars->ulsch_interference_power[i];
+      if(pusch_vars->ulsch_power[i]<1) pusch_vars->ulsch_power[i] = 1;
+      if(pusch_vars->ulsch_interference_power[i]<1)pusch_vars->ulsch_interference_power[i] = 1;
+    }
+
+    LOG_D(PHY,"%4.4d.%d power harq_pid %d rb %2.2d TBS %2.2d (MPR_times_Ks %d correction %d)  power %d dBtimes10\n", proc->frame_rx, proc->subframe_rx, harq_pid, ulsch[UE_id]->harq_processes[harq_pid]->nb_rb, ulsch[UE_id]->harq_processes[harq_pid]->TBS,MPR_times_100Ks,correction_factor,dB_fixed_times10(pusch_vars->ulsch_power[i])); 
+     
   }
 
   ulsch_channel_level(pusch_vars->drs_ch_estimates,

openair1/PHY/TOOLS/signal_energy.c

@@ -364,3 +364,66 @@ main(int argc,char **argv)
 }
 #endif
 
+#define SHRT_MIN -32768
+int32_t signal_power(int32_t *input, uint32_t length)
+{
+
+	uint32_t i;
+	int32_t temp;
+
+	__m128i in, in_clp, i16_min;
+	__m128  num0, num1;
+	__m128  recp1;
+
+	//init
+	num0 = _mm_setzero_ps();
+	i16_min = _mm_set1_epi16(SHRT_MIN);
+	recp1 = _mm_rcp_ps(_mm_cvtepi32_ps(_mm_set1_epi32(length)));
+	//Acc
+	for (i = 0; i < (length >> 2); i++) {
+		in = _mm_loadu_si128((__m128i *)input);
+		in_clp = _mm_subs_epi16(in, _mm_cmpeq_epi16(in, i16_min));//if in=SHRT_MIN in+1, else in
+		num0 = _mm_add_ps(num0, _mm_cvtepi32_ps(_mm_madd_epi16(in_clp, in_clp)));
+		input += 4;
+	}
+	//Ave
+	num1 = _mm_dp_ps(num0, recp1, 0xFF);
+	temp = _mm_cvtsi128_si32(_mm_cvttps_epi32(num1));
+
+	return temp;
+}
+
+int32_t interference_power(int32_t *input, uint32_t length)
+{
+
+	uint32_t i;
+	int32_t temp;
+
+	__m128i in, in_clp, i16_min;
+	__m128i num0, num1, num2, num3;
+	__m128  num4, num5, num6;
+	__m128  recp1;
+
+	//init
+	i16_min = _mm_set1_epi16(SHRT_MIN);
+	num5 = _mm_setzero_ps();
+	recp1 = _mm_rcp_ps(_mm_cvtepi32_ps(_mm_set1_epi32(length>>2)));// 1/n, n= length/4
+	//Acc
+	for (i = 0; i < (length >> 2); i++) {
+		in = _mm_loadu_si128((__m128i *)input);
+		in_clp = _mm_subs_epi16(in, _mm_cmpeq_epi16(in, i16_min));           //if in=SHRT_MIN, in+1, else in
+		num0 = _mm_cvtepi16_epi32(in_clp);                                   //lower 2 complex [0], [1]
+		num1 = _mm_cvtepi16_epi32(_mm_shuffle_epi32(in_clp, 0x4E));          //upper 2 complex [2], [3]
+		num2 = _mm_srai_epi32(_mm_add_epi32(num0, num1), 0x01);              //average A=complex( [0] + [2] ) / 2, B=complex( [1] + [3] ) / 2 
+		num3 = _mm_sub_epi32(num2, _mm_shuffle_epi32(num2, 0x4E));           //complexA-complexB, B-A
+		num4 = _mm_dp_ps(_mm_cvtepi32_ps(num3), _mm_cvtepi32_ps(num3), 0x3F);//C = num3 lower complex power, C, C, C
+		num5 = _mm_add_ps(num5, num4);                                       //Acc Cn, Cn, Cn, Cn, 
+		input += 4;
+	}
+	//Interference ve
+	num6 = _mm_mul_ps(num5, recp1); //Cn / n
+	temp = _mm_cvtsi128_si32(_mm_cvttps_epi32(num6));
+
+	return temp;
+}
+

openair1/PHY/TOOLS/tools_defs.h

@@ -431,6 +431,9 @@ int32_t subcarrier_energy(int32_t *,uint32_t, int32_t* subcarrier_energy, uint16
 */
 int32_t signal_energy_nodc(int32_t *,uint32_t);
 
+int32_t signal_power(int32_t *,uint32_t);
+int32_t interference_power(int32_t *,uint32_t);
+
 /*!\fn double signal_energy_fp(double *s_re[2], double *s_im[2],uint32_t, uint32_t,uint32_t);
 \brief Computes the signal energy per subcarrier
 */

openair1/PHY/defs_eNB.h

@@ -166,6 +166,8 @@ typedef struct {
   int32_t **ul_ch_magb;
   /// measured RX power based on DRS
   int ulsch_power[2];
+  /// measured Interference power based on DRS
+  int ulsch_interference_power[2];
   /// \brief llr values.
   /// - first index: ? [0..1179743] (hard coded)
   int16_t *llr;

openair1/SCHED/phy_procedures_lte_eNb.c

@@ -1605,7 +1605,7 @@ void fill_rx_indication(PHY_VARS_eNB *eNB,
 
   pdu->rx_indication_rel8.timing_advance = timing_advance_update;
   // estimate UL_CQI for MAC (from antenna port 0 only)
-  int SNRtimes10 = dB_fixed_times10(eNB->pusch_vars[UE_id]->ulsch_power[0]) - 10 * eNB->measurements.n0_subband_power_dB[0][0];
+  int SNRtimes10 = dB_fixed_times10(eNB->pusch_vars[UE_id]->ulsch_power[0]) - dB_fixed_times10(eNB->pusch_vars[UE_id]->ulsch_interference_power[0]);
 
   if (SNRtimes10 < -640)
     pdu->rx_indication_rel8.ul_cqi = 0;