Centralised Unit (CU)
The Centralised Unit is the part of a split 5G base station that runs the higher-layer, less time-critical radio protocols and can serve several distributed units.
What is Centralised Unit (CU)?
A 5G base station (gNB) can be split into a Centralised Unit, one or more Distributed Units and Radio Units. The CU hosts the RRC, SDAP and PDCP protocol layers. It is usually placed in a data centre or aggregation site and connects to its DUs over the F1 interface. It can be split further into control-plane and user-plane parts.