How to choose the best test equipment for 5G open RUs — Sangam

Prakash Sangam

The architectures of vRAN and open RAN with their disaggregation and open interfaces are opening the doors for smaller players, particularly radio unit (RU) vendors. As a result, there is now a pressing need for robust RU testing within the industry.

These new Open RAN RU (O-RU) players have different test equipment requirements from traditional vendors. They demand purpose-built, user-friendly, compact, cost-effective testing solutions to meet their needs.

Recognizing this demand, the Test and Measurement (T&M) industry has risen to the challenge and is actively developing the right solutions to address their unique requirements. LitePoint's IQFR1-RU is an excellent example of one such solution.

RU testing is critical for vRAN/open RAN deployments

The vRAN/open RAN architecture disaggregates the software and hardware components and enables multi-vendor interoperability. Its implementation depends on whether the operator is an existing (brownfield) or a new one (greenfield). For existing operators, the process typically involves two steps: first, implementing a single-vendor vRAN with open interfaces, and second, transitioning to a multi-vendor fully open RAN. New operators, on the other hand, can achieve this in a single step.

The key point to note is that both options significantly lower the entry barriers, allowing new players to enter the market. This trend is particularly evident in the RU space, where new original design manufacturers (ODMs) like Foxconn, LiteOn, Pegatron, Sercomm, WNC, and many others have already introduced a range of products. Many others are planning to jump into the fray soon. Most traditional RAN players support vRAN/open RAN and also offer O-RUs.

Operators will require hundreds of thousands of RUs with varying configurations, ranging from 2x2 MIMO to 64T64R, many spectrum bands, bandwidths over 400 MHz, etc. The sweet spot for new O-RU entrants appears to be 2x2 and 4x4 MIMO, Sub-6 GHz, and up to 100 MHz bandwidth, as these configurations are less complex, relatively easier to develop, and are well-suited to complement macro deployments with smaller indoor or outdoor cell sites. Additionally, the expanding ecosystem around these configurations can make them cost-effective. In a recent report, Stefan Pongratz, VP of Dell'Oro, said, "…although massive MIMO traction is increasing, from a volume perspective, 2x2 and 4x4 MIMO configurations make up more than 80% of overall shipments…."

From the operators' perspective, the deployment of a large number of RUs allows them to experiment with new vendors without risking the entire network. Because of the sheer volume, even a small cost-efficiency achieved per RU can result in substantial overall cost and power consumption savings.

However, the introduction of new interfaces and new entrants poses serious interoperability challenges. Specifically, the new standardized optical Front-Haul interface makes the O-RU testing unique compared to traditional RUs. Further, the critical role that O-RUs play in the overall system performance is making robust testing a fundamental requirement for the industry.

Unique testing needs of O-RUs

Traditional infrastructure vendors invest substantial amounts of money in building end-to-end testing infrastructure. The Test and Measurement (T&M) ecosystem has historically been tailored to meet their requirements. Together they have developed sophisticated, flexible, multifunction testing systems comprising multiple units that can be utilized for different network protocols, and types of radios, supporting varying technologies and configurations. These comprehensive testing solutions can cost tens of millions of dollars.

On the other hand, new O-RU players have distinct needs that differ from traditional vendors. Firstly, they may not require complete end-to-end testing if they solely focus on O-RUs. Secondly, they don't need the flexibility to support multiple configurations since many of them specialize in producing and selling high-volume RUs with a subset of features. Thirdly, they may not possess elaborate testing facilities and thus require compact testing solutions. Fourthly, they may lack teams of highly qualified test engineers who are proficient in configuring, operating, and troubleshooting complex test instruments. Furthermore, the cost is their most critical consideration, especially when scaling testing to hundreds of thousands of O-RUs.

Moreover, new O-RU players will also seek readymade automation software and tools to simplify their testing processes. They will want solutions that not only cover their design validation test scenarios but can also scale to the manufacturing environment.

Right solutions are emerging

Indeed, the T&M industry has recognized the challenge and is actively developing suitable solutions to cater to the unique needs of the O-RU market. An excellent example of such a solution is IQFR1-RU O-RAN Radio Unit Test System by LitePoint, a Teradyne company. This tester is a recent addition to LitePoint's comprehensive suite of wireless test solutions.


The IQFR1-RU is a compact, feature-rich, and high-performance RU testing kit specifically designed and built to address the requirements of O-RU vendors. Today's O-RU test solutions comprise multiple signal generators, a signal analyzer, a DU emulator, and RF interfacing components. In contrast, IQFR1-RU is designed as a single-box wrap-around solution for O-RUs, simplifying test setups. It is ideal for Design and Verification Testing  (DVT) and allows companies to scale seamlessly into production testing. It supports 3GPP Rel. 16 and the latest O-RAN Alliance radio specifications. It comes with a suite of software automation tools with many test cases preconfigured. The IQFR1-RU is being used by many O-RAN silicon and O-RU makers today.

Recognizing the market opportunity, other players in the T&M industry are following LitePoint's lead and are working on optimizing solutions for O-RAN product testing. It will be interesting to observe how this new market and competitive landscape develops in the coming months and years.

Prakash Sangam is the founder and principal at Tantra Analyst, a leading boutique research and advisory firm. He is a recognized expert in 5G, Wi-Fi, AI, Cloud and IoT. To read articles like this and get an up-to-date analysis of the latest mobile and tech industry news, sign-up for our monthly newsletter at, or listen to our Tantra's Mantra podcast.

Industry Voices are opinion columns written by outside contributors — often industry experts or analysts — who are invited to the conversation by Fierce Wireless staff. They do not necessarily represent the opinions of the Fierce Wireless editorial board.