feat(nr): implement rank-8 PDSCH

executables/nr-ue.c

@@ -763,8 +763,9 @@ void *UE_thread(void *arg)
 
   if (get_softmodem_params()->sync_ref && UE->sl_mode == 2) {
     UE->is_synchronized = 1;
-  } else {
-    //warm up the RF board
+  } else if (!IS_SOFTMODEM_RFSIM) {
+    // Warm up physical RF hardware. RFsim has no RF board to settle, and
+    // discarding 100 simulated frames only delays initial synchronization.
     openair0_timestamp_t tmp;
     for (int i = 0; i < 50; i++)
       readFrame(UE, &tmp, duration_rx_to_tx, true);