How does a RFID security access control system work?

by Vantage Security vantage security

Radio-Frequency Identification refers to the use of radio waves to read, capture, and interact with information saved on a tag. Tags are generally attached to objects, and can be read from several feet away. In addition, the tag doesn’t always have to be in the direct line-of-sight to initiate interaction.

An RFID tag is a wonderful and effective way to assign a unique identity to an object. Moreover, they do not need an internal power source, while a tag can be as small as a grain of black pepper. Meaning they are easily embedded almost anywhere — hence their popularity.

A basic RFID security access control system is made up of two parts: the tag, and the reader.


The RFID tag has an embedded transmitter and receiver. The actual RFID component contained in a tag has two parts: an integrated circuit for storing and processing information, and an antenna to receive and transmit a signal. The RFID tag has non-volatile memory storage, and can include either fixed or programmable logic for processing transmission and sensor data.

Tags can be passive, active, or battery-assistive passive.

A passive tag is the cheapest option, and features no battery. The tag uses radio energy transmitted by the reader.

An active tag features an onboard battery, periodically transmitting its credentials.

A battery-assistive passive tag also features a small onboard battery, but is only activated when in the presence of an RFID reader.

In addition, a tag may be either read-only, or read/write. A read-only tag has a factory assigned serial number used for identification in a database, while a read/write tag can have specific custom data written to the tag by the user.


The RFID reader has a two-way radio transmitter-receiver (transceiver), sometimes referred to as an interrogator. The transceiver transmits an encoded radio signal to interrogate the tag. The radio signal essentially wakes or activates the tag. In turn, the tag transponder converts the radio signal into usable power and responds to the reader.

Types of RFID Security Access Control System

We generally classify the type of RFID system by the type of tag and reader. There are three common combinations:


Passive Reader Active Tag (PRAT): The reader is passive, only receiving radio signals from an active tag. Because the tag is battery powered, the transmit/reception range can be from 0-2,000 feet (0-600m). As such, PRAT is a flexible RFID solution.

Active Reader Passive Tag (ARPT): The reader is active, transmitting an interrogator radio signal, receiving authentication signal replies from passive tags.

Active Reader Active Tag (ARAT): The reader is active, and interacts with active or battery-assistive passive tags.

The amount of information stored on an RFID tag varies. For instance, a passive tag may only store up to 1024 bytes of information — that’s just one kilobyte (KB). Laughable in terms of modern storage capacity, but enough to store a full name, identification number, birthday, SSN, credit card information, and so much more. The aerospace industry, however, uses passive ultra-high frequency RFID tags with 8KB storage to track part history over time. These could store a massive amount of personal data on.

Today, there are various areas where RFID Security Access Control System is being deployed.

Sponsor Ads

About Vantage Security Freshman   vantage security

1 connections, 0 recommendations, 33 honor points.
Joined APSense since, May 23rd, 2018, From Empire Heights Tower –A Business Bay, Dubai, UAE, United Arab Emirates.

Created on Aug 7th 2018 03:22. Viewed 571 times.


No comment, be the first to comment.
Please sign in before you comment.