O-RAN radio units (O-RUs) need to conform with both 3GPP standards and O-RAN ALLIANCE specifications.
Fronthaul conformance tests as defined by the O-RAN ALLIANCE verify the proper behaviour of fronthaul interfaces and ensure that the O-RU designs are interoperable with the O-RAN distributed unit (O-DU).
O-RAN ALLIANCE Global PlugFests are periodic events organized and co-sponsored by O-RAN ALLIANCE to enable efficient progress of the O-RAN ecosystem through well-organized testing and integration.
Vendors and providers come together to test, evaluate and verify their products and solutions. The O-RAN ALLIANCE Global PlugFest Fall 2023 was held in 16 labs across eight countries.
Performing O-RU conformance tests in an automated setup was one of the focus areas at the Japan O-RAN PlugFest. There, O-RU vendors like NEC had the opportunity to verify the conformance of their platforms with test and measurement solutions from Rohde & Schwarz and VIAVI Solutions amongst others.
The setup used at the O-RAN PlugFest in Japan to validate NEC’s O-RU consisted of the following test solutions:
- The R&S SMM100A vector signal generator and R&S FSVA3000 signal and spectrum analyzer from Rohde & Schwarz emulated a real-world radio environment by generating, capturing and analyzing RF signals. For in-depth debugging R&S VSE vector signal explorer analysis software was used allowing to access detailed measurement results.
- The TM500 O-RU Tester from VIAVI Solutions has implemented the O-DU side of the M-plane and C/U-plane functionality which was necessary for the configuration of the interface with the O-RU and to exchange I/Q data over the Open Fronthaul.
- The O-RU Test Manager application from VIAVI has provided a single point of control for the integrated system and has ensured a seamless, fully automated user experience throughout the test setup.
With this setup, automated conformance tests per specification O-RAN.WG4 CONF.0-v09.00 was performed. Additionally, the operation of Open Fronthaul (O-FH) control plane (C-plane), user plane (U-Plane), synchronization plane (S-plane) and management plane (M-Plane) was verified. The setup also supported test cases from 3GPP TS 38.141-1 for base station (BS) conducted conformance transceiver testing.