5G • RAN
CSS
Common Search Space
PDCCH search space monitored by all UEs for broadcast control information, paging, and random access.
Technical Explanation
Common Search Spaces (CSS) are defined for broadcast and group control signaling. Types include Type0-PDCCH CSS (SIB1), Type0A-PDCCH CSS (OSI), Type1-PDCCH CSS (RACH Msg2/Msg4 with RA-RNTI/TC-RNTI), Type2-PDCCH CSS (Paging with P-RNTI), and Type3-PDCCH CSS (group power control and SFI).
Key Functions
- Carries broadcast DCIs for system information and paging
- Monitors random access response and contention resolution grants
- Supports aggregation levels 4, 8, and 16 for high coverage reliability
Specifications
3GPP TS 38.213
Interfaces
Uu
Related 5G Concepts
Want to memorize 5G concepts like this one?
Study it with SuperMemo SM-2 spaced repetition flashcards.