Small Cell Forum (SCF) has released a paper outlining the key test configurations for 3GPP TS38.141 compliance testing of split 6 products using the SCF nFAPI 2.0 interface. Led by Forum members Keysight Technologies and Picocom, the paper aims to inform operators and integrators on how split 6 products can be tested, with specifications derived from 3GPP standards.

SCF’s comprehensive suite of 5G FAPI/nFAPI specifications stimulate innovation and competition across the small cell ecosystem by supporting multi-vendor interoperability within products and between different products of small cell networks, architected within the 3GPP defined disaggregated functional split framework.

Trends identified in SCF’s 2021 Market Forecast showed plans for Open RAN disaggregated networks—with considerable interest in split 6 for shorter range indoor enterprise, campus and private networks. Operators and systems integrators will need to integrate disaggregated network components including the CUs, DUs and RUs from different vendors, and for integration/testing these need to be compliant with 3GPP test specification TS38.141. However, the units need to be able to be tested individually as well as part of an integrated system and this paper lays out how this can be done. SCF228 S-RU and S-DU Test Support:

  • Provides an overview of 5G split 6 S-RU and S-DU products and architectures
  • Examines the impact of split 6 on 5G base station compliance testing
  • Develops options and proposes different solutions for testing S-RU and S-DUs
  • Delivers an overview of TS38.141 test approach for split 6 products.

“Open RAN disaggregated networks facilitate vendor diversification with radio units and distributed units supplied by different vendors. It is imperative that vendors can be confident their units are compliant when tested as a complete system, and a test solution particularly for S-RU needed developing.” said Vicky Messer, director of Product Management at Picocom.

“The test methodology recommended in this paper enables vendors to perform conformance testing without requiring any specialized test mode on their S-RU, thus removing a major pain point in the development and deployment process.” added Balaji Raghothaman, chief architect at Keysight Technologies.

“The SCF standardized nFAPI interface is an Open RAN interface that can be used across the ecosystem of S-RU vendors and S-DU vendors, but it is essential that it can also be used by test equipment vendors,” said Prabhakar Chitrapu, chair of Small Cell Forum. “This document from SCF is a timely companion to the nFAPI specifications, and is expected to accelerate the development, testing and deployment of S-RU and S-DU based disaggregated Open RAN solutions."