SIB Scheduling in LTE

System Information Blocks (SIBs) in LTE

System Information Blocks (SIBs) carry essential network configuration information in LTE. Below is a table summarizing SIB1 to SIB15, their functions, and examples.

SIB	Function / Purpose	Example
SIB1	- Contains PLMN, TAC, Cell ID, Scheduling Info, and Access Barring. - Defines cell suitability for camping.	📶 UE checks SIB1 to determine if it can camp on the network (e.g., PLMN = 404-45 for Jio India).
SIB2	- Provides RACH configuration, UL power control, and timer values. - Contains parameters for PRACH, PUSCH, PUCCH.	🔄 UE reads SIB2 for random access parameters to initiate RACH.
SIB3	- Governs cell reselection criteria (same frequency). - Defines Qrxlevmin, S-IntraSearch.	📡 UE in idle mode reads SIB3 to decide whether to reselect a different intra-frequency cell.
SIB4	- Contains neighboring intra-frequency cell information for reselection.	🔄 UE reads SIB4 to check neighbor cells on the same EARFCN.
SIB5	- Provides inter-frequency neighbor cell reselection parameters.	📶 UE checks SIB5 for cells on different frequencies (e.g., LTE band 3 → band 40).
SIB6	- Contains UTRA (3G) neighbor cell information for reselection.	🔄 UE reads SIB6 to switch from LTE to UMTS (3G) if LTE coverage is weak.
SIB7	- Contains GERAN (2G) neighbor cell information for reselection.	📡 UE reads SIB7 to switch to 2G (GSM) in poor LTE conditions.
SIB8	- Contains CDMA2000 (1xRTT) neighbor cell information.	📶 Used in CDMA/LTE networks like Verizon for fallback to 1xRTT.
SIB9	- Broadcasts Home eNB information (for closed subscriber groups).	🏠 UE checks SIB9 to determine if it is allowed to access a femtocell.
SIB10	- Sends Earthquake & Tsunami Warning System (ETWS) primary notification.	⚠️ Emergency alert received via SIB10 when an earthquake is detected.
SIB11	- Sends ETWS secondary notification (detailed info).	🌊 UE gets detailed tsunami warning via SIB11.
SIB12	- Provides Commercial Mobile Alert System (CMAS) notifications.	🚨 Emergency broadcast messages like government alerts.
SIB13	- Broadcasts MBSFN (Multicast-Broadcast Single Frequency Network) configuration for LTE Broadcast.	📺 Used for TV/video streaming in LTE-broadcast-enabled networks.
SIB14	- Contains additional ETWS notifications.	🚨 Further warning messages beyond SIB10 & SIB11.
SIB15	- Provides GPS assistance data for A-GPS (Assisted GPS).	📡 UE uses SIB15 for improved GPS positioning in LTE.

---

Key Points

• SIB1 is the most important as it determines whether a UE can camp on a cell.
• SIB2-5 help with random access and cell reselection.
• SIB6-8 assist in inter-RAT reselection (3G, 2G, CDMA).
• SIB10-12 are used for emergency alerts (ETWS, CMAS).
• SIB13-15 handle multicast, GPS, and additional warnings.