What is CPRI?
CPRI is an industry standard defining the electrical and logical interface between the Radio Equipment Controller (REC/BBU) and the Radio Equipment (RE/RRH) in base station and C-RAN architectures. It specifies how digitised IQ samples of the radio signal are transported over the fronthaul link.
How Does CPRI Work?
CPRI carries raw IQ samples using a time-division multiplexed (TDM) frame structure over dedicated fibre. The interface has very strict latency requirements (typically less than 100 µs round trip) and the bandwidth scales with the number of antenna ports and carrier bandwidth. eCPRI (enhanced CPRI), defined for Open RAN, uses Ethernet transport and a higher-layer functional split to dramatically reduce fronthaul bandwidth requirements.
Use Cases
Traditional C-RAN fronthaul between BBU pools and remote radio heads, eCPRI/O-RAN fronthaul between O-DU and O-RU in Open RAN deployments.
3GPP / Standards Reference
CPRI Specification v7.0, eCPRI Specification v2.0, O-RAN Alliance CUS-Plane Specification
Related Terms
C-RAN | RRH | Fronthaul | Open RAN | O-RAN
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This glossary entry is part of the 5GWorldPro Complete 5G Glossary. To go deeper into 5G architecture and technology, explore our 5G Training courses.
