TM500 O-RU Tester

Validating the timing and synchronization between an emulated O-DU and O-RU. This is important as the timing ensures that all aspects of the management, control and user planes are synchronized and eliminates the risk of latencies or lost/dropped packets.

Ensuring inter-operation of the O-DU with different vendor O-RUs, which are all supposed to operate according to the O-RAN standard. This sounds easy and is one of the key goals with Open-RAN architecture, but in practice, it comes with challenges. Different vendor O-RUs may have different delay profiles, different software implementations and a different performance, meaning they may not plug, play and operate correctly.

The latency, maximum throughput and handling of certain features, such as beamforming, may not produce the same performance between two different vendors. Due to the flexibility that the O-RAN standard encompasses, testing must address the complexity of using different vendor combinations while expecting consistent results.

O-RU conformance, interoperability, and performance, including real-time generation of the O-RAN C/U-plane messaging for the IQ data stream

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In partnership with Rohde & Schwarz

The TM500 O-RU Tester is designed with two versatile test setup modes to cater to a variety of testing requirements and budget constraints. Each setup mode is tailored to provide specific benefits and functionalities:

TM500 O-RU Tester with VSA/VSG Test Setup

• High Precision: Utilizes a standalone Vector Signal Analyzer (VSA) and Vector Signal Generator (VSG) for broad capability signal analysis and generation, ideal for detailed performance assessment.
• Flexibility: Offers the ability to test a wide range of frequencies and bandwidths, supporting diverse O-RU configurations and compliance testing needs.
• Customizability: Adaptable to a variety of test scenarios, allowing users to configure and modify test parameters according to specific network demands.
• Use Case: Best suited for R&D and lab environments where precision and flexibility in signal manipulation are critical.

Proven in the spring 2022 O-RAN ALLIANCE Plugfest:

TM500 O-RU Tester with PVT360A Test Setup

• Integrated Solution: Incorporates the PVT360A, a compact, single-box VSA/VSG instrument that enhances test efficiency and reduces operational complexity.
• High Throughput: Designed for rapid testing with capabilities for simultaneous multi-port testing, reducing test times significantly.
• Scalability: Offers scalable options from basic single-generator setups to advanced configurations with multiple generators and analysers.
• Use Case: Ideal for the earlier stages of development when multiple engineers must work in parallel to perform functional and system level testing and where speed, efficiency, and cost-effectiveness are paramount.

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Why VIAVI and R&S:

• Solution designed for scalability
• Streamlined single control point for simplified usage
• Singular support ownership post-sales through VIAVI
• Compatible with TM500 for performance testing
• Leverage VIAVI RANtoCore market dominance, rooted in the industry-leading TM500
• Use R&S top-tier RF capabilities and market leadership

Complimentary to conformance testing, this goes beyond the O-RAN standards to test at the 3GPP level. We call this Direct Performance Testing (DPT) where the O-RU is tested with an emulated O-DU over the 3GPP stack. The advantages of doing this are numerous and enables a much smoother integration with a real O-DU ahead of E2E testing.

• Gets the best performance out of each O-RAN NW element prior to E2E testing
• Brings efficiency gains ahead of integration with O-DU and E2E performance testing e.g. eliminates issues that E2E testing can mask.
• Reduces "pointing the finger" culture e.g., elements from different vendors
• Raises the profile of a vendor NW components e.g., the O-RU conformance test cannot guarantee that it will workover the 3GPP 5G stack.

O-RU, O-DU and O-CU are tested in conjunction with a real or emulated core network. One of the aims is to obtain the best performance across all network components. This is a typical type of test that would be performed by a System Integrator or OTIC laboratory.

Watch a demonstration of end-to-end testing here:

Capacity testing scales the numbers of User Equipment devices (UEs), with carriers. This is a more realistic test that would emulate a real deployment. This type of test would ensure the best Quality of Service (QoS) for each user under different mobility and fading conditions.

O-RAN Alliance - Virtual Exhibition