February 18, 2020
5g, IoT, Technical, Innovation
5G promises to transform the way people access and interact with data. In particular, 5G NR mmWave—one of the three “types” of 5G—has enormous potential, delivering dramatically higher speed, higher capacity, and lower latency.
By integrating 5G NR mmWave into enhanced Mobile Broadband (eMBB) devices—such as laptops, networking equipment, gaming devices, and systems that support augmented reality (AR) and 3D/8k video content—a whole new world opens up thanks to the impressive performance increases that 5G NR mmWave delivers.
In addition to enhancing entertainment experiences and boosting productivity, 5G NR mmWave will help enable entirely new Internet of Things (IoT) applications— including those centered around autonomous vehicles, immersive AR and virtual reality (VR) experiences, as well as connected infrastructures for Smart City applications.
Here’s the thing, though: 5G NR mmWave’s innovations, including its use of newly opened millimeter wave spectrum between 24 GHz and 53 GHz, does not just deliver blazing speed and other performance enhancements. These 5G NR mmWave innovations also bring with them a unique set of new design considerations that engineers need to consider when creating an eMBB product.
By paying attention to the seven following 5G NR tips, designers can successfully avoid any product development pitfalls and successfully integrate 5G NR mmWave modules into their products, allowing them to take advantage of all that this new cellular standard has to offer.
It’s a fact of life: high-speed operation tends to generate heat, which means that a 5G NR mmWave device can run hot. Mitigating this heat requires a careful approach to thermal design. There are several ways to tackle this challenge, via either software or hardware modifications.
Software algorithms can monitor when operating temperatures get too high and then take corrective action to keep things cool by temporarily slowing data transmission, for example, or limiting the data being pushed to the modem. Alternately, a heat sink can be mechanically attached to the 5G NR mmWave module to draw off excess heat.
The bottom line? For any 5G NR mmWave application, it’s important to anticipate where hot spots might occur in the design and take any necessary steps to prevent the system from overheating.
High-speed operation doesn’t just mean more heat – it also means more wattage is required. Consider the following: if you add a low-power 5G NR mmWave antenna module to an eMBB device, the system will require an additional 4 watts of power. Adding a high-power mmWave antenna, meanwhile, could require as much as an additional 50 watts of power. Understanding these power requirements can help ensure you don’t run into any design complications down the road, after the development process is well underway.
5G NR mmWave is a significant departure from previous generations of cellular—and that means some of the hardware is a notable departure as well. Case in point: 5G NR mmWave antennas, which need special handling compared to other cellular antennas.
For example, in order to provide good mmWave antenna performance in all directions, mmWave antennas need to be carefully calibrated to optimize antenna transmission. Performance can easily be impacted by other electronics in the system.
The challenges don’t stop there. Another consideration with 5G NR mmWave antennas is that the plastic chosen to house the mmWave portion of the design needs to be as clear and penetrable as possible, since any signals in the range between 24 and 36 GHz—where 5G NR mmWave operates—can have difficulty passing through opaque materials.
Taking these unique antenna considerations into account is crucial, and it doesn’t end at the design stage, as we’ll see in the next tip.
You’re not done with the antenna yet: the 5G NR mmWave antenna needs to be calibrated again during manufacturing to ensure that the antenna performs properly.
This secondary calibration typically takes place in an anechoic chamber (a room that is non-reflective and echo-free), which isolates the radio frequency (RF) waves coming from the system so they can be characterized in isolation. Software tools offered by the 5G NR mmWave module provider can simplify the tasks of optimizing antenna characteristics and minimizing distortion, so keep an eye out for this option.
We’re all familiar with the ubiquitous USB port, and with many 4G cellular device designs, USB was the interface of choice. However, PCI Express (PCIe) – the standard interface for high-speed components on motherboard designs – is emerging as the better choice for 5G NR mmWave. This is because even the highest-performing version of USB—namely, USB3—can only support the minimum data-speed capabilities for 5G NR mmWave.
Additionally, USB3 has proven challenging to use and integrate at higher speeds, adding extra complications to system design. Also, the roadmap for PCIe promises to better keep pace with the ongoing evolution of cellular than USB. For all these reasons, many suppliers are starting to standardize on PCIe for their mobile broadband host interfaces and drivers.
The key takeway? Companies that have relied on USB in the past shouldn’t plan on doing so in the future and should take time now to get acquainted with PCIe.
From a regulatory point of view, a mmWave antenna module is inextricably tied to its host platform. This means that certification focuses less on the module level and more on the system level. This is a different—and broader— approach to device certification than what companies might traditionally be used to. Certification can’t be achieved simply by antenna performance alone; the system as a whole needs to pass muster.
To make things all the jollier, certification requirements around 5G NR mmWave can vary substantially from carrier to carrier, and the 5G NR mmWave piece is still evolving – which means specific requirements aren’t always easy to obtain. It’s a bit like aiming at a moving target.
Product designers can save time and money during the development process by working with a module provider who can not only help characterize the system but also help navigate the challenges of regulatory and carrier-specific certification.
Network deployment architectures are evolving, and there will likely be several different architectural standards in play for some time. For example, the legacy technology-oriented Non-Standalone Option 3 (NSA Option 3) architecture will overlap and coexist with the newer Standalone Option 2 (SA Option 2) architecture for a period of time.
What’s important here is that you don’t want to inadvertently “brick” a perfectly good eMBB device by only having it be compatible with one of these network architectures. It’s best to use a module that supports both standards, ensuring that the device can seamlessly transition to newer standards like SA Option 2 once they are available from a carrier.
Keep in mind that this isn’t a complete list of 5G NR tips, in addition to the above areas, there are other important things designers need to keep in mind as they develop new 5G NR mmWave products, including how to use the latest security technologies to protect the much larger amounts of data being transmitted. The 5G NR tips above, however, provide a great starting point, and partnering with a cellular expert like Sierra Wireless, with decades of leadership in cellular deployments of all kinds, can further smooth the path forward.
In addition to its extensive cellular technical expertise, Sierra Wireless addresses the concerns of 5G product developers with their devices, solutions, and services. For example, Sierra Wireless offers detailed thermal models of their modules, so developers can address the overall thermal design before they start working with actual hardware samples. When it comes to antennas, Sierra Wireless provides a software tool that is pre-loaded with characterization data to save time when placing and characterizing the antenna module. Additionally, Sierra Wireless is using the latest Qualcomm® 5G chipset—the SDX55—for its 5G NR mmWave cellular modules, which are compatible with both NSA Option 3 and SA Option 2 architectures.
Simply put, if there’s a design challenge around using 5G NR mmWave, Sierra Wireless has put careful thought into how best to address it.
Ready to get started? Start with Sierra and download our white paper, 5G Tips for Designers, to learn more on how you can keep your 5G design and development timelines on track, so you can quickly bring to market new IoT products that transform your business.
Get innovation delivered to your inbox. Sign up for our blog and stay on top of the very latest from Semtech (formerly Sierra Wireless).
