LTE: How does an UE come to know about its own DCI over the PDCCH ?

Question

N numbers of UEs can be scheduled at a particular TTI. So How does an UE get to know its own DCI ?

Answer 1

Every DCI message carries carries a set of information, which need to be protected as well as make sure that packet is received by intended UE. Each DCI packet has CRC for error-correction and CRC is scrambled with UE-CRNTI.

Whenever an UE receives a DCI packet over the PDCCH, it de-scrambled CRC with its own C-RNTI.
If de-scrambling operation is successful then only it go head to process the packet else it discards the received packet.

Answer 2

A UE gets assigned a Temporary C-RNTI via the Random Access Response Message.