5G • 5G-Advanced (Rel-18)
Network-Controlled Repeaters (NCR)
3GPP Rel-18 Smart Network-Controlled Repeater Architecture
Smart RF repeaters controlled directly by the gNodeB via side-control signaling, steering beams dynamically to bend mmWave around obstacles without costly baseband hardware.
Technical Explanation
Conventional RF repeaters blindly amplify both signal and noise, causing self-oscillation and network interference. Standardized in Rel-18 (TR 38.867), Network-Controlled Repeaters (NCR) feature a control connection to the gNodeB. The gNodeB commands the NCR's beamforming weights, transmit timing, and power levels in real time, steering coverage around street corners at a fraction of the cost of a full base station.
Key Functions
- Amplifies and steers millimeter wave beams without expensive baseband demodulation hardware
- Receives real-time beam steering and timing commands directly from the serving gNodeB
- Eliminates noise accumulation and self-oscillation common in legacy analog repeaters
- Bends high-frequency 5G signals around urban street corners and into building lobbies
Specifications
3GPP TR 38.867, TS 38.300 (Rel-18)
Interfaces
Uu (Side-Control)RF Front-End
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