What Are RF Shields and Why Are They So Important?

Radio and other electromagnetic waves propagate through every inch of space, and they can induce currents in wiring and other electrical components.

In sensitive applications, that can’t be allowed. To deal with this problem, modern designs in many industries implement RF shields that protect delicate electrical components from any incoming radio interference.

What Is an RF Shield?

An RF shield is any solution that blocks radio waves from passing through. In general, these solutions rely on metal casing around electrical components to absorb and disperse the incoming or outgoing waves.

There are many different materials and configurations that can go into making an RF shield for any individual application.

RF shielding protects devices from interference that can impact their operation and even cause lasting damage.

Depending on the sensitivity and nature of any device, the specifications for RF shields can vary widely.

Some require thick, specialized shielding, while others only need minimal shielding to ensure proper protection.

Most types of RF shielding work by creating a Faraday cage. When an incoming radio wave comes in contact with a continuous covering of conductive metal, it becomes dispersed across the surface.

The effect can be achieved with a literal cage made up of a grid of wires or by using a solid metal covering for electrical components.

Why Are RF Shields Necessary?

When a radio wave comes into contact with a wire, it can induce an electrical current. That’s how radio communications work, with the receiving antenna picking up the signal intentionally. However, this can create major issues when electronics pick up signals unintentionally.

In delicate electronics, signals can be of a low enough current that the noise created by radio interference can severely degrade the signal. This can ruin the signal, whether it’s a cellphone call or the image generated by medical scanning equipment.

Significant interference can even induce enough current to damage sensitive electronics.

As computer chips and other microelectronics continue to shrink in size, they are at an ever-increasing risk of this damage as the amount of current required to induce damage decreases.

RF shields are also used to keep radio interference in. If some component generates significant interference, it can be isolated with an RF shield to prevent interference with other components or devices.

Where Are RF Shields Used?

RF shields are used across a wide range of industries. Electronics of all kinds can require RF shields when their use could be affected by interference. As electronics become smaller and more sensitive, the need for RF shields is steadily increasing.

RF shields play a vital role in telecommunications infrastructure. Certain elements of devices and infrastructure need to be shielded from their own interference and interference from the network in general.

Medical devices implement RF shields to provide protection from interference with incredibly sensitive signals. MRIs and other imagining equipment can be affected by even minimal radio interference, requiring RF shielding at multiple levels to ensure proper operation.

Avionics is another industry that integrates RF shields into every piece of equipment. Airplanes, satellites, and other applications use sophisticated instruments for navigation and other processes. RF shielding protects these from the increased interference that can prove devastating at high altitudes.

These are a few examples where RF shields play a particularly prominent role, but they are also found in devices of all kinds. Consumer devices, lighting, cars, industrial equipment, and so much more need RF shields to protect against the many sources of interference in today’s world.