Basics of Radio Frequency Identification (RFID)

In this video, the presenter is explaining all about RFID (Radio Frequency Identification) Technolgy.

What is RFID?

RFID is a technology which works on radio frequency and it is used for the auto-identification for the different object.

The RFID system mainly consists of two parts.

1. RFID Reader or Interrogator
2. RFID Tags

In this RFID system, this RFID reader continuously sends radio waves of a particular frequency. If the object, on which this RFID tag is attached is within the range of these radio waves then it sends the feedback back to this RFID reader. And based on this feedback, RFID reader identifies the object.

RFID tags

Now, three different kinds of RFID tags are commercially available.

1. Passive tags
2. Active tags
3. Semi-passive tags

These passive tags do not have any power supply. They used to get their power from the incoming radio waves from the Readers.

While active tags have a power source for their internal circuitries. And for sending the response to the reader also, it uses its own power supply.

In the case of semi-passive tags, they have a power supply for internal circuitries, but for sending the response it relies on the radio waves received from the Reader.

Operating Frequency

This RFID system is mainly operated in three frequency bands.

1. LF: Low-Frequency band
2. HF: High-Frequency band
3. UHF: Ultra High-Frequency band

The exact frequency of operation varies from country to country.

Operating Principles

Most of the RFID systems operate on any of this two principles.

1. Load Modulation
2. Backscattered Modulations

Applications of RFID

1. Institutions: Library, Hospitals, Schools, and Colleges
2. Transportation and Logistics
3. Access Control
4. Sports
5. Animal Tracking

Courtesy: ALL ABOUT ELECTRONICS