Accelerate the rollout of 5G infrastructure test solutions

Operators and equipment suppliers are adopting Open Radio Access Network (RAN) technologies, including O-RAN Alliance standards, to minimize infrastructure development costs and reduce barriers to new product innovation.

The global deployment of the fifth-generation mobile network (5G) continues to advance, and new services are gradually available to enhance user experience and implement challenging applications.

 

It is important to realize that the 5G network is not only an improvement in the performance of 4G technology (in terms of upload and download speed), or a simple upgrade to existing standards and protocols. In addition to typical mobile phone applications, 5G technology will be able to support higher-level services and applications, such as autonomous vehicles, vehicle-to-vehicle and vehicle-to-everything communication (V2V and V2X), virtual reality (VR) and augmented reality (AR), HD video streaming and IoT applications. The new features provided by 5G networks can be summarized as follows:

 

eMBB (Enhanced Mobile Broadband): 5G's higher bandwidth will allow smooth and efficient use of applications such as augmented reality, video streaming, and video conferencing;

mMTC (Massive Machine Type Communication): 5G will be able to manage large-scale connections (thousands of simultaneously connected devices and millions of connections) without overloading the network. This will allow effective management of complex IoT applications, such as smart homes, smart cities, smart grids, etc.;

URLLC (Ultra Reliable Low Latency Communication): This service will provide support for all applications that require real-time behavior and extremely low latency, such as factory automation, industrial control systems, autonomous vehicles, smart grids, and surgical robots.

The role of testing

Because of the rapid technological progress and 5G will place high requirements on network infrastructure, a comprehensive test plan from the laboratory to the field, from RAN to the core is required. In addition, operators and equipment suppliers are adopting Open Radio Access Network (RAN) technologies, including O-RAN Alliance standards, to minimize infrastructure development costs and reduce barriers to new product innovation.

 

As shown in Figure 1, the 5G network test mainly includes three stages:

 

Validation: The technology was validated in the laboratory before deployment.

Verification: Verify the network and its services on site through appropriate field tests.

Visibility: This stage aims at ensuring, optimizing the network and achieving profitability.

Figure 1: The three key stages of 5G testing (Figure provided by VIAVI Solutions)

 

5G test solution

The deployment of 5G networks and solutions requires a test and measurement company to help vendors and operators test their 5G telecommunications equipment. This involves not only wireless communication testing, but also optical fiber measurement, field measurement using a spectrum analyzer, and so on.

 

"In terms of telecommunications testing, we will test 3G, 4G and 5G networks, including open radio access networks," said Owen O'Donnell, VIAVI Solutions wireless solutions manager, in an interview with EE Times Europe. "Operators and equipment manufacturers around the world are adopting Open RAN to minimize infrastructure deployment costs and reduce barriers to new product innovation."

 

VIAVI Solutions stated that it has developed a comprehensive test suite that includes modules for laboratory verification, field deployment and service assurance.

 

One thing that needs to be clarified is the difference between laboratory and field testing. Labs are places where vendors who develop new base stations or 5G core networks want to test what has been developed to ensure that they are actually working in accordance with requirements or applicable standards. Telecommunications standards, such as those set by 3GPP, are developing very rapidly, and vendors need to develop their products to meet the new standards.

O'Donnell said: "Suppliers need to verify that they have actually correctly understood and implemented the standards. This is where VIAVI Solutions comes in. Therefore, we will help them go to the laboratory, and we will help them by simulating those elements. No."

 

For example, if a supplier wants to test a base station, VIAVI can provide solutions that simulate the behavior of thousands of UEs (such as mobile phones), send relevant messages to the base station and test whether it processes these UE messages correctly. At the other end of the base station, a core network can be simulated, so that the base station forwards the call setup request to the core network and gets the correct return from it. Therefore, the base station under test can use two VIAVI products, a UE simulator and a core network simulator. From a standard compliance point of view, this will help base station manufacturers to ensure that their base stations work properly.

 

O'Donnell said: "This test can be done in the laboratory. In the laboratory, things may fail without affecting anyone in the live network." "But when you enter the actual live network on site At that time, you also need to perform other tests, such as beamforming tests."

5G should provide users with better throughput, more connections, and more IoT devices.

"Operators have specific KPIs they want to achieve, but we don't know what these numbers are until we enter the site and measure the actual throughput and the number of connections to the terminal base station," O'Donnell said.

 

In 5G, the core network is completely different from the 4G core network. The core network has been completely re-developed and redesigned, and new elements have been added. Importantly, those independent elements of the core network can now be provided by different vendors.

 

"We need to make sure that all these elements work together, and then they work together with actual traffic," O'Donnell said.

 

This is exactly where TeraVM, one of the tools based on the VIAVI lab, comes in. TeraVM is an application simulation and security performance solution that provides comprehensive test coverage for application services, wired and wireless networks. Figure 2 shows how TeraVM and other VIAVI tools can be used to verify the 5G SBA (Service Based Architecture) virtual mobile core and its components.

 

Figure 2: Using TeraVM for 5G testing (Figure provided by VIAVI Solutions)

 

When people cannot easily access the laboratory (especially during a pandemic, such as the recent Covid-19), then they will move the test to the cloud. Therefore, they can access the system from home or from any location with IP connectivity. To meet this need, VIAVI puts its system test solution in the cloud. Users log in to Amazon Web Services, can select and reserve some instances, upload the test plan to these instances, and test on the cloud platform. Therefore, the test solution will only be used when necessary, that is, the time required to test the function.