Why is Certifying MulteFire Devices Important?

Scott Fischel, MFA Certification Work Group Chair, interviews Luisa Natividad Caro García of DEKRA Testing and Certification, S.A.U.

To support the MulteFire 1.9 GHz (sXGP) Certification Program, the MFA announced its first MFA Authorized Test Lab (ATL) at DEKRA in Yokohama, Japan. In November 2020, the MFA announced that DEKRA’s lab in Malaga, Spain, was the MFA’s second ATL, approved for performing MulteFire 1.0 Certification testing. DEKRA has been an active supporter of the MFA’s efforts to deliver MulteFire technology in unlicensed and shared spectrum bands for private LTE networks and is the world’s largest unlisted expert organization in the TIC (testing, inspection, certification) industry.

We spoke with DEKRA’s Luisa Natividad Caro García (Nati) about the key role certification plays in ensuring industry standards and the certification process for MulteFire 1.0 devices:

What is your professional experience with certification testing?
For more than 20 years, I have been involved in testing and certification activities for various technologies such as Bluetooth, Wi-Fi, 2G, 3G, 4G/LTE and more, in different capacities including project management and team leader. Currently, as the Wireless Laboratory Manager at DEKRA Testing and Certification, S.A.U., I manage a lab consisting of 17 employees.

Why is a certification program critical for the success of industry standards?
Certification programs play a key role in ensuring devices can successfully interoperate, as manufacturers can implement standards in different ways. Certification programs utilize test labs, such as the DEKRA ATLs, to ensure devices work as expected and to provide the proper guidance if not.

In addition, they can play a large role in expanding an industry standard’s ecosystem. Once vendors certify the first products, this encourages additional vendors to follow suit. In this case, we expect the recently certified Nokia MulteFire 1.0 user equipment to foster growth within the MulteFire ecosystem.

What are the benefits of certifying my device at the DEKRA ATL? Can’t vendors prove specification conformance on their own?
DEKRA’s vast experience with certification testing is unmatched, as we not only offer testing services but provide recommendations on how to solve the potential conformance and interoperability issues. This consulting aspect is particularly beneficial, as opposed to relying on internal testing. In addition, participating in the MulteFire Certification Programs is a crucial step to minimize the risk of issues when products are in the field.
As DEKRA is an official MFA Authorized Test Lab (ATL), vendors with MFA-certified devices can add the MFA logo seal to their products. This offers the end-user assurance that the device will work properly, and in-turn positively influence purchasing decisions.

What is DEKRA’s experience with industry standard certification programs?
DEKRA offers services in a wide variety of aspects related to certification and is present in many key regions offering regulatory, conformance, interoperability, performance, usability and field testing. We have extensive experience in providing consulting services for associations to define their certification program and provide tests for standard development. DEKRA helps to create customized test tools for certification testing and has adapted its existing tools to match MulteFire requirements.

What devices are eligible for MulteFire 1.0 Certification? Is there anything I need to do to prep my device for MulteFire 1.0 Certification testing?
For the MulteFire 1.0 Certification Program, DEKRA tests eNodeB (eNB) radio access network elements and user equipment (UE). We test this combined ecosystem of eNBs and UEs, making sure that the implementation of MulteFire 1.0 standard in the device is correct, according to the current scope of certification defined by the MFA.

Those interested in viewing the detailed requirements for MulteFire 1.0 Certification testing are encouraged to review the project management document as provided by the MFA Certification Work Group. In summary, manufacturers must provide the final hardware, and preferably also the software. It is expected that your devices will be close to final commercialization.

The vendor will provide the corresponding antennas for their devices, the Evolved Packet Core (EPC) in case of eNB certification, as well as the required guidelines to connect their pieces to the ecosystem.

What tests are conducted for MulteFire 1.0 Certification?
The MulteFire 1.0 Certification Program tests for both conformance and interoperability. Conformance testing ensures that devices have properly conformed to the MulteFire 1.0 standard and is done in a lab environment using specialized test equipment to perform RF parametric and protocol testing. Interoperability testing helps to test coexistence with other technologies. Since MulteFire 1.0 technology operates in unlicensed spectrum, it is important to make sure devices implementing MulteFire 1.0 successfully coexist with Wi-Fi and similar technologies.

To test for interoperability, DEKRA checks that the device works with reference implementations in environments that represent typical use cases. This involves checking how UEs interact with eNBs, testing vendor eNBs to a reference UE and vice versa. To determine how the device interacts with Wi-Fi, DEKRA creates data transfers within the Wi-Fi link and MulteFire link and assesses the impact of both.

Does DEKRA and the MFA Certification Work Group have any plans to test for conformance metrics in the future?
Ultimately, our goal is to expand the conformance testing for MulteFire. This expansion could potentially include the use of third-party tools such as Sanjole WaveJudge analyzer to test specific modes and conformance metrics.

How long does certification take?
In accordance with full MFA Certification Work Group (CWG) requirements, certification could take anywhere between one to two weeks, dependent on the availability of reference devices.

What are some common development errors that could be avoided prior to certification testing?
In our experience, manufacturers often do not follow the Technology Specifications in detail when developing the product for testing. The manufacturer should consider the requirements of the technology specifications as well as the certification testing requirements during the design and development stages so that the product under test is more likely to be compliant. Otherwise, when failures are encountered at the certification stage, a re-design will be required to correct those failures, leading to higher costs and delays to time to market.

In addition, the vendor should consider the specific sample preparation requirements that are applicable to the device for the certification programs. Often, we see the vendor does not provide the prepared samples for testing, e.g. without the required RF, power and data connectors/cables, without the needed test modes, or without enabling internal logging. However, it is important to note that the certification scheme should indicate the mandatory sample preparations that must be compiled in order to make a device suitable for certification, or the certification scheme will provide alternate test procedures and/or waivers for devices that cannot comply with such requirements by design.

What if my device doesn’t pass MulteFire 1.0 Certification?
If your device does not pass MulteFire 1.0 certification, the next steps are to identify where the issue is, and DEKRA will help provide consultation to solve this issue. As the MulteFire 1.0 Certification program progresses, this consultation will improve as we gain more experience in MulteFire 1.0 technology testing.
MFA Ecosystem Expansion

The MFA thanks Nati for sharing her experience with DEKRA certification testing and her insight into the importance of certifying devices. We look forward to continuing collaboration with the DEKRA ATLs as the MulteFire ecosystem expands

If you’d like to participate in the MulteFire 1.0 or MulteFire 1.9 GHz Certification programs, please fill out this form to get in touch with the MFA Certification Authority.