Proper normalization to noise power estimation in chest_dl

lib/src/phy/ch_estimation/chest_dl.c

@@ -282,11 +282,15 @@ static float estimate_noise_pilots(srslte_chest_dl_t *q, uint32_t port_id, srslt
   
   /* Compute average power. Normalized for filter len 3 using matlab */
   float norm  = 1;
+  if (q->average_subframe) {
+    norm = 32;
+  } else {
     if (q->smooth_filter_len == 3) {
       float a = q->smooth_filter[0];
       float norm3 = 6.143*a*a+0.04859*a-0.002774;
       norm /= norm3;
     }
+  }
   float power = norm*q->cell.nof_ports*srslte_vec_avg_power_cf(q->tmp_noise, nref);
   return power; 
 }