◼️5G RAN interfaces with 5G Core.
◼️NG Interface
gNB is connected to the 5G core network by means of NG interface. Through to paths are:
- gNB is connected to the AMF by the means of the NG control-plane part (NG-c)
- gNB is connected to the UPF by the means of NG user-plane part (NG-u)
- One gNB can be connected to several APFs/UPFs for the purpose of load sharing and redundancy
◼️Xn Interface
Concreting gNBs to each other, the main use is
- Support active-mode mobility
- Support dual connectivity
- Multicell Radio Resource Management (RRM) functions
- Lossless mobility between neighbouring cells by means of packet forwarding
◼️There is also a standardized way to split the gNB into two parts as follows:
▪️Centralized Unit (gNB-CU)
- This applied for Non-real time applications, consists of the high layers of protocol stack RRC, PDCP, SDAP.
▪️Distributed Unit (gNB-DU)
- This applied for Real-Time applications, contains lower layers of protocol stack RLC, MAC, PHY.
◼️ F1 Interface Connecting between Centralized Unit and Distributed Units.
◼️Uu Interface
This interface is well known as it's Connecting between the gNB and UEs users Equipments.
AMF: Access Mobility Function
UPF: User Plane Function
#5G #ran #communication
