What is RFID? How it works and its applications – A Beginner’s Guide

22/09/2023

Nội Dung

What is RFID?

Definition: RFID stands for Radio Frequency Identification. It is a technology that enables remote identification using radio waves, allowing data stored on a chip to be read contactlessly via radio frequency transmission at distances ranging from 50 cm to 10 meters, depending on the type of RFID tag.

How RFID Works

RFID uses non-contact radio wave technology to transmit data. By attaching RFID tags to assets or goods, users can uniquely and automatically identify those items—enabling asset tracking and real-time inventory updates. RFID has taken automatic identification (Auto ID) technology to the next level by allowing tags to be read without the need to align a scanner directly with the tag’s surface. Depending on the type of RFID tag used, the read range can exceed 20 meters.

RFID has come a long way since its first applications, which were used to identify friendly or enemy aircraft during World War II. Over time, the technology has continuously improved in terms of usability and cost-efficiency, which has enabled its widespread adoption across various industries and areas of daily life.

Types of RFID

There are three main frequency ranges used in RFID transmission:

Low Frequency (LF): 125–134 kHz
High Frequency (HF): 13.56 MHz
Ultra High Frequency (UHF): 433 MHz and 860–960 MHz

LF- Low frequency

LF tags have longer wavelengths and can penetrate thin layers of metal. LF systems are ideal for reading objects with high water content, such as fruits or beverages. However, the read range is limited to just a few centimeters or inches. LF RFID tags are commonly used in access control and animal tagging.

HF- High frequency

HF tags work relatively well around metal surfaces and goods with moderate to high water content. Typical HF RFID systems have a maximum read range of about 1 meter. HF tags are widely used in library management, patient flow tracking, and check-in systems.

UHF- Ultra high frequency

UHF tags offer significantly longer read ranges (from 30 meters up to over 100 meters) and faster data transmission speeds—meaning they can read more tags per second compared to LF and HF tags. However, because UHF radio waves have shorter wavelengths, their signals are more susceptible to interference and cannot pass through metal or water.

Due to their high data transmission rates, UHF RFID is used in a wide range of applications, such as:

Automatically recording the movement of goods through warehouse control gates
Tracking race performance at finish lines in sporting events
Electronic toll collection
Parking access control systems

There are two types of UHF RFID: Active RFID and Passive RFID

Tiêu chí	Active RFID	Passive RFID
Definition	Active RFID tags have their own power source and continuously transmit signals to readers.	Passive RFID tags do not have an internal power source; they receive energy from the reader and use it to send back data.
Frequency Bands	433 MHz	860- 960 MHz
Read range	30- 100 m	25m (tiếp xúc gần)
Battery	Có	Không
Power source	Built into the tag	Supplied by the reader
Operation	Continuous tracking	Only activated and read upon reader request
Lifespan	Limited by battery (typically 3–5 years)	Unlimited
Advantages	Very long read range, lower infrastructure costs than passive systems, large memory capacity, high data transmission speed.	Low cost per tag, long read range, available in many shapes and sizes, globally standardized, high data transmission speed.
Disadvantages	Higher cost per tag, larger size, shipping limitations (due to battery), signal interference from metal and liquids, subject to certain EU regulations.	Higher cost for readers, moderate memory capacity, susceptible to interference from metal and liquids.
Applications	Due to higher costs, often used for high-value assets (e.g., pipelines, cargo containers, machinery).	Low-cost and flexible, widely used in inventory, asset management, livestock tracking, event timing, and event management.

Common Applications of RFID

RFID technology is increasingly being adopted across various industries due to its benefits in terms of data accuracy, labor efficiency, operational cost reduction, and time savings. Some typical applications include:

Timing for sports competitions
Asset management
Pharmaceutical tracking
Inventory tracking
Laundry and textile management
Library lending and return systems
Toll collection
Infant tracking in hospitals
Asset tracking in jewelry stores
Logistics and supply management
Contactless automated payments
Event attendee management
Security control and access management

Explore detailed RFID solutions across various industries provided by 1Gate here