How UE distinguished from SIB modification paging to which SIB modified?

Question

UE Receives SIB modification through paging message. But how UE will get to know which SIB is modified?

Answer 1

Hi,
UE don't get any notification of which MIB/SIB is being modified, UE will be in DRX connected mode, UE wakes up and read the downlink shared channel(PBCH and PDSCH). But will be unaware of which MIB/SIB are modified

Comments

After receiving paging, then How UE will acquire SIB, UE should know which SIB is modified right?

Answer 2

Example : SIB-3 is modified at the eNB [In case of LTE]

1. paging message will be broadcasted to all the UEs
2. UEs will receive PRNTI (0XFFFE) scrambled PDCCH, decodes it (when it wakes up at idle mode or connected mode DRX) and know the location of PDSCH (RRC paging message)
3. Paging message will be received/decoded at PDSCH channel (PDSCH->PCH->PCCH)
4. RRC will (ASN) decode the PCCH/paging message being received
5. If the IE systemInfoModification is set to true in the paging message, then RRC will send SI acquisition request to PHY
6. PHY will acquire SIB-1 and then RRC decodes SIB-1; periodicity and windowLength of SIB-3 will be obtained.
7. RRC will send these information to PHY; the PHY will acquire SIB-3 and forwards it to RRC.
8. RRC will (ASN) decode modified SIB-3 and stores it.