Showing posts with label 5G. Show all posts
Showing posts with label 5G. Show all posts

Friday, July 6, 2018

RRC state Machine in 5G 38.331



A UE is either in RRC_CONNECTED state or in RRC_INACTIVE state when an RRC connection has been established. If this is not the case, i.e. no RRC connection is established, the UE is in RRC_IDLE state.


- RRC_IDLE: 
- A UE specific DRX may be configured by upper layers;
- UE controlled mobility based on network configuration;
- The UE:
             - Monitors a Paging channel;
             - Performs neighbouring cell measurements and cell (re-)selection; - Acquires system information

- RRC_INACTIVE:
- A UE specific DRX may be configured by upper layers or by RRC layer;
- UE controlled mobility based on network configuration;
- The UE stores the AS context;
- The UE:
            - Monitors a Paging channel; - Performs neighbouring cell measurements and cell (re-)selection;
           - Performs RAN-based notification area updates when moving outside the RAN-based notification area;

- RRC_CONNECTED:
- The UE stores the AS context;
- Transfer of unicast data to/from UE;
- At lower layers, the UE may be configured with a UE specific DRX;
- For UEs supporting CA, use of one or more SCells, aggregated with the SpCell, for increased bandwidth;
- For UEs supporting DC, use of one SCG, aggregated with the MCG, for increased bandwidth;
- Network controlled mobility within NR and to/from E-UTRAN;
- The UE:
             - Monitors a Paging channel;
             - Monitors control channels associated with the shared data channel to determine if data is scheduled for it;
             - Provides channel quality and feedback information;
             - Performs neighbouring cell measurements and measurement reporting;
             - Acquires system information.