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5G is quickly making waves across the electronics industry. These faster, higher-bandwidth networks offer extensive benefits for consumers and businesses alike, but they require a significant shift in hardware. Among these necessary changes, 5G electromagnetic interference (EMI) shielding is one of the most challenging for electronics engineers.
The need for reliable EMI shielding is nothing new. However, 5G introduces new obstacles, spurring a wave of innovation as developers work around them.
Compact EMI shielding
One of the biggest challenges with 5G networks and EMI shielding is 5G’s high frequency. The higher-frequency bands, particularly millimeter-wave, have wavelengths between 1 and 10 mm, resulting in higher capacity and throughput but shorter ranges. As a result, they rely on distributed networks of small cells instead of large, centralized towers, requiring smaller EMI shields.
Providing sufficient shielding in a smaller form factor is challenging. Processing ultra-high–frequency signals in less space also makes overheating a more prominent issue, but there is less room for heatsinks.
This challenge is leading to a surge in compact shielding and thermal management designs. As Faraday cages and heatsinks become unviable, attention turns to rethinking shielding materials. Thermal gels and lightweight alloys like aluminum provide effective alternatives to larger conventional materials.
Smaller open apertures
Similarly, 5G EMI shielding must consider any open apertures on the device. Shorter wavelengths create a larger risk of RF signals leaking through non-conductive or open areas. While these apertures are often avoidable, charging ports or cooling vents pose an issue.
Better internal thermal management can help by reducing the need for open apertures for cooling. Using batteries or energy-harvesting systems instead of wired power connections has a similar effect by removing the need for cable ports.
This solution works well for Industry 4.0 applications, which happen to be some of 5G’s biggest use cases today. Designing devices that forgo charging wires in favor of contained systems meets this need while reducing EMI risks from open charging ports.
Environmental shielding
As 5G grows, it will spur broader IoT adoption. Consequently, 5G devices must contend with challenging environmental conditions, requiring protection from heat, humidity, water and dirt on top of EMI.
Conventional shielding techniques and materials are effective against EMI but not environmental hazards. Device designers could implement separate EMI shielding and environmental protections, but this makes products bulky and complex.
A better alternative is to provide both defenses in a single enclosure. Metal-embedded silicone is a well-suited material for this application, as it resists water and extreme temperatures while blocking EMI. If a shield needs more conductivity, corrosion-resistant metals like silver provide more reliability than more conventional copper, as silver is much more resistant to oxidation and is more conductive. Silver-plated copper offers an effective middle ground between high resilience and cost-effectiveness.
Flexible shielding
Another innovation coming out of 5G EMI shielding is the growing prominence of flexible shielding. Rigid metal cages are quickly becoming outdated as 5G raises the need for smaller and environmentally resistant protection. Flexible fabric, foam and epoxy alternatives are taking their place. Using epoxy or foam lets the shielding form a complete seal around the protected components.
Flexible shielding is particularly advantageous for devices using system-in-package (SiP) designs instead of the more popular system-on-chip (SoC). While SoCs deliver better performance, SiPs offer more design flexibility and are suited for mobile gadgets using 5G networks. However, they also require more partitioning of individual components, making flexible shielding more desirable.
Thermal management innovations
5G also introduces more thermal management concerns in EMI shielding. 5G infrastructure and devices handle more data simultaneously in smaller packages, leading to higher temperatures. This obstacle has led to several important thermal management innovations.
Phase-change materials (PCMs) provide passive cooling, taking up less space and energy than active systems or conventional heatsinks. However, they previously haven’t been conductive enough to work in electronics-cooling applications. Recent research shows that by adding more conductive materials to PCMs, their efficacy significantly improves, making them viable for 5G applications like phones or IoT devices.
Changes to how 5G devices operate can help, too. Unlike 4G, 5G does not require constant transmission, enabling lower power consumption. Designing 5G base stations and IoT devices to go into sleep mode by default when not sending data will lower their energy usage, reducing resulting heat.
5G devices need complete EMI shielding to ensure that they operate properly at all times. While this may be a challenging undertaking, it paves the way for widespread technological improvements. As a result, the development of more resilient, flexible and effective EMI shielding can benefit the entire electronics industry, not just 5G devices.
About the author
Emily Newton is a technical writer and the editor-in-chief of Revolutionized. She enjoys researching and writing about how technology is changing the industrial sector.
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