Description
A radio frequency (RF) signal refers to a wireless electromagnetic signal used as a form of communication, if one is discussing wireless electronics. Radio waves are a form of electromagnetic radiation with identified radio frequencies that range from 3Hz to 300 GHz. Frequency refers to the rate of oscillation (of the radio waves.) RF propagation occurs at the speed of light and does not need a medium like air in order to travel. RF waves occur naturally from sun flares, lightning, and from stars in space that radiate RF waves as they age. Humankind communicates with artificially created radio waves that oscillate at various chosen frequencies. RF communication is used in many industries including television broadcasting, radar systems, computer and mobile platform networks, remote control, remote metering/monitoring, and many more.
Features
Radio Frequency (RF) Systems are the most widely used systems today. RF EAS system works like this: A label -- basically a miniature, disposable electronic circuit and antenna -- 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). Sensors (gates/pedestals) based on EAS-RF technology 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 prefer this because it virtually eliminates false alarms!
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