5g split

5G networks, the term "split" typically refers to the functional split between different network components in the radio access network (RAN). The 5G RAN architecture introduces a concept known as functional split to enable greater flexibility, scalability, and efficiency in the deployment and operation of radio access networks. The functional split divides the processing tasks between the central unit (CU) and the distributed unit (DU) in the RAN.

Here is a technical explanation of the 5G split architecture:

1. Central Unit (CU):
   • The CU is the central processing unit responsible for higher-layer functions in the radio access network.
   • It handles functions like radio resource management, connection management, and mobility management.
   • The CU is typically located in a centralized data center, making it easier to scale and manage.
2. Distributed Unit (DU):
   • The DU is responsible for lower-layer functions related to the radio interface.
   • It handles functions such as physical layer processing, beamforming, and modulation/demodulation.
   • DUs are distributed closer to the cell sites or even at the antenna site (depending on the deployment scenario), reducing latency and improving radio performance.
3. Functional Split Options:
   • The functional split can be categorized into different options based on the division of tasks between CU and DU.
   • Common functional split options include:
     • Option 2: CU handles the higher-layer functions, while the DU handles lower-layer functions up to the physical layer.
     • Option 7-2x: CU handles the higher-layer functions, and the DU is further split into a lower DU (L-DU) and an upper DU (U-DU). The L-DU handles lower-layer functions, and the U-DU handles upper-layer functions closer to the CU.
4. Front Haul:
   • The communication link between the CU and DU is known as the front haul.
   • Front haul connectivity is critical for ensuring low-latency and high-throughput communication between the central and distributed units.
   • Depending on the functional split option, different fronthaul requirements may exist, such as capacity and latency considerations.
5. Benefits of Functional Split:
   • Flexibility: The functional split allows network operators to optimize their networks for specific use cases by choosing the appropriate split option.
   • Scalability: It enables easier scaling of network capacity by independently scaling the CU and DU components.
   • Efficiency: By distributing lower-layer functions closer to the edge, the network can be more efficient in terms of latency and resource utilization.

5G functional split is a key architectural concept that defines how processing tasks are divided between the central and distributed units in the radio access network. The flexibility offered by different functional split options allows operators to tailor their networks to specific performance and deployment requirements.