'Tis the Season for Interfering LED Devices

When you think of an interferer affecting your WiFi or other communications system, the first thing that probably comes to mind is a communications device. Yet many non-communication sources of interference also exist. Light-emitting diodes (LEDs), for example, can affect the reception of FM radio, digital television (DTV) broadcast, very high frequency (VHF) communications, and Long Term Evolution (LTE) cellular up to 300 m. Many online forums cite examples of interference issues after installing LED lights in an office, workshop, or even a car. During the holiday season, the abundance of decorative LED lights in the environment make such interference even more likely.

In the U.S., LED light bulbs comply with Federal Communications Commission (FCC) rules stating they will not cause harmful interference to communications services. The rules acknowledge that LED lighting devices generate RF energy either through electronic power conversion or digital circuitry. Because these devices were not created to radiate RF energy, they fall under the category of unintentional radiators. Often, the interference stems from the lighting device’s electronic driver, which operates in the radio frequencies.

Although LEDs receive a lot of attention around this time of year, many other non-communications interferers exist in a typical household. Every appliance running on electricity generates an electromagnetic field. These fields may block or hinder the communications waves trying to travel through them, just as physical objects like insulation may do. Such appliances range from refrigerators to washing machines, dishwashers, toasters, and the oft-cited culprit, the microwave oven.

In such a crowded environment, communications manufacturers must satisfy or even surpass the attenuation required for unwanted emissions. They also must perform compliance testing beyond the traditional frequency range. In case these steps fail, they should offer tips to users in case they are faced with interference problems.

The prevalence of technology and communications in today’s world gives interference an increasingly high chance of developing. This trend results in the higher demands placed on communications manufacturers. In addition, new strategies are needed to detect, classify, locate, and mitigate interferers causing harm. Mitigating interference requires spectrum monitoring and signal analysis. For applications such as interference detection, users perform both of these steps in situ - often in dense signal environments. Our solutions can help you successfully navigate this process to find the source of your interference. In the meantime, if you start having issues with the communications in your home this holiday, make sure you check whether a router is located near some LED lighting decorations.

Click here for more information on our spectrum monitoring and signal analysis solutions.