5 Materials That Can Interfere with RFID Signals and How to Overcome Them

In the implementation of an RFID system, the success of tag reading is not only determined by the quality of the reader or antenna. Environmental factors and the materials surrounding the tag also play a large role. Some types of material can cause RFID interference, which hinders reading distance, reduces accuracy, or even makes the tag completely unreadable. Understanding the characteristics of these materials is an important step before implementing an RFID system in the field.

Types of Materials That Inhibit RFID Performance

The following are five materials that most often inhibit RFID performance, along with their explanations.

1. Metal

Metal is the main enemy of RFID technology, especially UHF RFID. Metal surfaces reflect and absorb radio waves, making it difficult for the signal from the reader to reach the tag or return to the antenna. As a result, reading becomes unstable or fails.

In industrial applications such as manufacturing and warehouses, this condition is often encountered on iron racks, machinery, and heavy equipment. To overcome this, on-metal RFID tags or special spacers are usually used to maintain optimal performance.

2. Liquid

Liquid materials, especially water, are very effective at absorbing radio waves. Because the human body is mostly composed of water, this phenomenon is also often seen in wearable applications or tracking items based on liquids.

In the food and beverage industry, bottles containing liquid can significantly reduce the RFID reading distance. Common solutions include using special antenna designs, proper tag placement, or selecting a tag type designed for liquid environments.

3. Human Body

The human body is a source of RFID interference due to its high water content. When a tag is close to the body, RF energy will be absorbed, causing reading performance to decrease.

This condition often occurs in access control systems, event management, or tracking assets carried by people. Therefore, the antenna position and tag orientation need to be carefully designed to minimize this obstruction.

4. Carbon and Carbon Fiber

Carbon-based materials, such as carbon fiber, have conductive properties that can interfere with RFID signal propagation. This interference is often unnoticed because their appearance is similar to plastic or other light materials.

In the automotive and aerospace industries, the use of carbon fiber is quite massive. Implementing RFID in this environment requires special testing to ensure tags remain consistently readable.

5. Active Electronic Devices

Electronic devices such as electric motors, inverters, and industrial machinery can generate electromagnetic noise. This noise has the potential to disrupt communication between the reader and the RFID tag.

Factory environments with many active machines often experience this condition. Adjusting the reader power, frequency selection, and strategic antenna placement are key to reducing the impact.

Conclusion

RFID interference is not just a technical problem, but a challenge for overall system design. Metal, liquid, the human body, carbon materials, and electronic devices are the five main materials that need to be anticipated from the start.

By understanding the characteristics of each material, businesses can design more accurate and reliable RFID solutions. The selection of the tag type, antenna position, and proper system configuration will greatly determine the success of the implementation in the field.

As an end-to-end RFID solution provider, TUDI is ready to help you analyze potential RFID interference and design a system that suits your business environmental conditions. Consult your needs with the TUDI expert team to get effective and sustainable RFID solutions.

Read Also: 6 Misconceptions About RFID Technology and the Facts