Table Of Contents
- There’s more than one way to build an effective RF shield.
- RF shielding techniques should match the intended application.
- Working with a high-quality manufacturing partner is among the most effective RF shielding techniques.
Shielding devices from radio frequency interference (RFI) is nothing short of essential if you work in aerospace, defense, electric vehicles, mass transit, consumer electronics, telecommunications or a growing number of other industries. You know you have to do it, but do you know how you should do it?
As it turns out, there is more than one way to shield a device from RF signals. Each of these RF shielding techniques comes with special considerations for both design and manufacturing, and the resulting RF shields each perform differently in different environments and applications.
This blog post should help clear up any confusion. Read on to learn eight key RF shielding techniques you should know about.
RF shielding is about much more than design. It’s also about manufacturing. Make sure your chosen RF shielding technique is as effective as it should be by working with a high-quality manufacturing partner like Modus Advanced. Contact our team to get started.
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RF Shielding Gaskets
Gaskets that mitigate, reflect or redirect incoming RF signals are not RF shields on their own, but they are an important and often overlooked of all kinds of RF shields. Like other gaskets, RF shielding gaskets can be found in and surrounding openings in a part or device — in this case, the RF shield itself.
There’s nothing inherent in the shape of a gasket, which can vary widely depending on the manufacturing method used, that helps it mitigate RF signals. The “technique” behind this RF shielding technique is all about the conductive filler material used inside the elastomeric gasket material.
These filler materials are usually metal particles dispersed throughout the elastomer. When RF signals hit the gasket, the conductive filler materials mitigate them by absorbing, reflecting or dispersing them.
O-rings are much like gaskets when they are used to block RF signals. Typically, O-rings are made from metal, but when you need them to shield a part or device from RF signals, you will almost always need them to resemble the constitution of RF shielding gaskets: an elastomeric base filled with conductive metal particles.
Solid RF Shielding Enclosures
In some applications, you need a completely solid enclosure surrounding a highly sensitive device to ensure that no RFI can reach it. In such cases, you may need a solid RF shielding enclosure.
These are simply metal cases that completely surround their protected components. They have to be properly grounded to prevent certain RFI from entering them, but when they are, they’re highly effective.
Sometimes, components that are sensitive to RFI are also sensitive to overheating and must be vented to prevent it. In such a case, how do you keep out RF signals? With a vent shield. These shields can look a lot of different ways, but they are most commonly designed like solid enclosures but with a small vent or vents.
They are metal and keep RF signals from entering through the vent by keeping the vent holes small enough to bounce RFI away but let air pass through.
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Faraday cages are made from wire mesh that is placed around the object that needs to be protected from RFI. As radio signals hit the cage, the metal wire reflects and redistributes the signal evenly around the cage’s exterior, effectively eliminating the signal’s potential to reach the protected component inside.
Board RF Shields
Board RF shields are an RF shielding technique that requires extreme precision. In part, that’s because they are usually so small. These shields can take several forms, including as Faraday cages and solid enclosures, but they are placed on circuit board components to block signals or keep them from leaving.
Cable RF Shields
Certain cables are susceptible to RFI or may even produce unwanted RFI themselves. The only RF shielding technique that can accommodate this unique scenario is the cable RF shield. Cable RF shields can be metal foil, spiraled wiring or wire mesh wrapped around the cables from end to end.
Some RF shields are the size of buildings. That’s because they need to shield building-sized equipment from receiving or emitting RFI. The most common example of an RF shielded facility is an MRI room.
Shielded facilities are usually formed like solid enclosures or vented shields. A conductive metal sheet covers all six sides of the room that needs to be shielded to keep RF signals from leaving or entering.
Bonus RF Shielding Technique: Work with the Best Manufacturing Partner
You can choose the perfect RF shielding technique for your device and application and still have it fall flat. Usually, the reason for that is going to be that you chose the wrong manufacturing partner. The wrong manufacturing partner is the one that cuts corners on quality, does not advise on design and engineering concerns and works with dated or ineffective tools and materials.
The right manufacturing partner, on the other hand, is Modus Advanced. We lead the pack in RF shield manufacturing because we put quality first in everything we do. It also helps that we maintain a staff that is more than 10% engineers.
In any case, don’t fall into the trap of lower-quality manufacturing partners and watch your RF shield design fail. Instead, partner with Modus Advanced and get it done right. Give us a call at 925-960-8700 or contact us online to get started.