Radio Network Controller
- Node B
- RNC
- SGSN
- GGSN
A radio network controller (RNC) (English for radio network controller ) is a network element of the UMTS mobile radio digital network.
General
To a radio network controller a number of UMTS base stations (Node B) are connected. The interface between a RNC and a Node B is referred to as lub interface. An RNC together with its attached Node Bs a Radio Network Subsystem (RNS). RNA or RNC are connected to the UMTS core network. The interface between RNC and RNA, and the UMTS core network is the lu interface.
Tasks
The essential task of a Radio Network Controller is to manage the connected to it Node Bs and its radio resources. This includes the administration of the codes for WCDMA channels, the RF power control ( power control) as well as the initiation and coordination of the cell change (handover). Different from the Base Station Controller of the GSM network, which correspond to the radio network controllers in the UMTS network, adjacent RNCs may be interconnected via the Iur interface to one another. The Iur interface is essentially required for the so-called soft handover.
To obtain a basis for decisions Power Control and Handover, level and quality measurements are carried out and communicated to the measurement results of the RNC mobile station and base station.
Roll
- Controlling RNC - RNC A warrants to the Node Bs connected to it, for which he manages the radio resources, the role of the so-called Controlling RNC. For each Node B there is exactly one Controlling RNC.
- Serving RNC - with respect to a connection between user equipment (UE) and the UTRAN assumes a role of the serving RNC, the RNC. The serving RNC manages the connection between the UE and the UTRAN, and controls the Iub interface for the UE. For each UE having a connection to the UTRAN there is exactly one serving RNC.
- Drift RNC - An RNC in the role of a drift RNC supports a Serving RNC with it manages radio resources.