phy: do not put random bits in unused DCI

This used to be done to ease power estimation in the UE,
but this is not correct. Let's put no energy in the REs
with no DCI data, which is what needs to be done.

Plus it consumes a lot of CPU because of calling taus()
way too much.

openair1/PHY/LTE_TRANSPORT/dci.c

@@ -291,24 +291,8 @@ uint8_t generate_dci_top(uint8_t num_pdcch_symbols,
   y[0] = &yseq0[0];
   y[1] = &yseq1[0];
 
-  if (IS_SOFTMODEM_BASICSIM) {
-    /* this should be the normal case
-     * but it has to be validated for all the various cases
-     * so let's just do it for the basic simulator
-     */
-    //  memset(e, 2, DCI_BITS_MAX);
-  } else {
-    // reset all bits to <NIL>, here we set <NIL> elements as 2
-    // memset(e, 2, DCI_BITS_MAX);
-    // here we interpret NIL as a random QPSK sequence. That makes power estimation easier.
-    for (i=0; i<DCI_BITS_MAX; i++)
-      e[i]=taus()&1;
-
-    /* clear all bits, the above code may generate too much false detections
-     * (not sure about this, to be checked somehow)
-     */
-    //memset(e, 0, DCI_BITS_MAX);
-  }/* BASIC_SIMULATOR */
+  /* reset all bits to <NIL>, here we set <NIL> elements as 2 */
+  memset(e, 2, DCI_BITS_MAX);
 
   e_ptr = e;
   VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_GENERATE_DCI0,1);