R.F. Electronic Article Surveillance Systems

Radio Frequency (RF) Electronic Article Surveillance (EAS) Systems are widely used throughout the world in order to protect all manner of merchandise and to help reduce the incidents of theft.

RF tags and labels are getting smaller all the time and various configurations are available to suit almost every type of product, package or container.

The RF EAS system works in the following way:

A label - basically a miniature, disposable electronic circuit - and antenna which is attached to a product responds to a specific frequency emitted by a transmitter antenna (usually one pedestal of the entry/exit gate). The response from the label is then picked up by an adjacent receiver antenna (the other pedestal). This processes the label response signal and will trigger an alarm when it matches specific criteria. The distance between the two gates, or pedestals, can be up to 80 inches wide. Operating frequencies for RF systems generally range from 2 to 10 MHz (millions of cycles per second); this has become standard in many countries. Most of the time, RF systems use a frequency sweep technique in order to deal with different label frequencies.

Sometimes both the transmitter and receiver are combined in one antenna frame -- these are called mono systems and they can apply pulse or continuous sweep techniques or a combination of both.

Our Sensors (gates/pedestals) emit a low-energy RF pulse, which "listens" for the tag. This technology, known as digital signal processing, actually "learns" about its surroundings so that it can accurately distinguish between the tag signal and extraneous noise. Store employees love this because it virtually eliminates false alarms!