Running With O-RAN

5G standards are opening the world of hardware development to anyone that can build the best, cost-effective products. At the heart of many of those products is the system on a chip (SoC) that needs to be verified within the context of the overall system. Many new companies are in 5G chip development now, delivering custom solutions that match the many configurations need for different rural and city density needs. Because there are so many hardware and software configurations and use cases, verification of the silicon is critical. That is why Mentor developed an integrated pre- and post-silicon verification solution.

O-RAN is key

The key protocol for 5G is the Open Radio Access Network (O-RAN) standard. O-RAN is an open standard defined by a large alliance of telecommunication industry members. It defines open, interoperable interfaces, APIs, RAN virtualization, and big-data enabled RAN intelligence. Underlying the standard is the goal to utilize the same physical cables that are used within an Ethernet network.

O-RAN is a protocol that “sits” on top of the evolved Common Public Radio Interface (eCPRI) or IEEE 1914.3 standard for Radio over Ethernet (RoE), as Figure 3 shows. The fiber lines connect to an Ethernet network, the eCPRI or IEEE1914.3 define the fronthaul packets, and O-RAN defines how the devices communicate with these packets.

Fig. 1: O-RAN defines how devices communicate with packets.

O-RAN is a complex standard, with a six layer stack of functionality and there are currently 9 technical workgroups that are defining the specification. It is the architectural foundation for companies to build out intelligent 5G systems. O-RAN is so critical to the 5G ecosystem that in June, Mentor formally announced membership in the O-RAN Alliance to help drive interoperability requirements for 5G silicon. As an alliance member, Mentor focuses on verification and validation requirements for open standards-based, highly-configurable network development.

As the O-RAN standard develops, it is important to monitor any changes or additions and to make them available in the software that is at the center of the pre- and post-silicon solution. With an agile software architecture, new standard features can be implemented quickly with no changes required for the tool hardware itself. All the standard protocols are fully implemented in Mentor’s X-STEP software, which can be released to update any existing X-STEP customer.

Pre- and post-silicon verification

The pre-silicon solution (Figure 2) centers on using the Veloce emulation platform to simulate the silicon DUT. The test environment defines the base station control and antenna data that drives the X-STEP software. This software provides the protocols required to support 5G solutions. Teams can verify their system at speed, orders of magnitude faster than RTL simulation. VirtuaLAB models provide virtual representations of protocols, like Ethernet, to enable pre-silicon verification of interfaces on the SoC.

Fig. 2: Pre-silicon verification solution.

In the post-silicon solution (Figure 3), the actual silicon is available and verification teams begin their work in the lab using the X-STEP hardware to generate, capture, and analyze bit-accurate fronthaul traffic for any line rate. The same test environment is used and the same X-STEP software onboard the hardware platform supports the standards for 5G. With 100% visibility and control over fronthaul traffic, X-STEP ensures full interoperability between fronthaul devices that are in the early development phase, as well as in the field.

Fig. 3: Post-silicon verification solution.

The take-away

The open and flexible 5G standards are driving new development of highly customized hardware. This means that verification is key. By providing a single pre- and post-silicon verification solution the reuses the test environment and provides support of standards such as O-RAN, teams can bring their tested solutions to market faster. To learn more about the pre- and post-silicon 5G verification solution, read our new whitepaper, 5G SoCs Demand New Verification Approaches.