In this article, we will learn about RFID Technology and its Design, different types, working, applications, advantages and limitations.
Introduction
RFID (Radio Frequency Identification) is a wireless communication technology that uses radio waves to automatically identify tagged objects or things. It transmits data from an RFID tag to an RFID reader using an antenna, enabling accurate and real-time tracking.
In this technology, the RFID reader and RFID tag are the two basic components used, where data is digitally encoded in an RFID tag that can be read by the RFID reader.
The RFID reader is a device that has multiple antennas that transmit radio waves and receive radio signals back from the RFID tag. The RFID tag uses radio frequency to communicate its information, including its own identity, to nearby readers.
RFID technology is capable of storing, recovering, and re-recording a vast amount of data (up to four million characters and thousands of bytes) on a small chip and transmitting it through radio frequency or radio waves.
RFID technology is widely used in several commercial and industrial applications to search, identify, track, and communicate with various objects, people, items, or things. It automates the collection of data and reduces human effort and error. During the reading from the tag, line-of-sight and item-by-item scanning are not required. Multiple tags can be read by an RFID reader simultaneously, increasing efficiency.
Components of RFID Technology
Basically, RFID technology consists of four components. They are:
- RFID Tags
- RFID Reader
- Antenna
- Software
1. RFID Tags
It is a smart tag consisting of an electronic microchip that has a unique identification number embedded inside, as well as an antenna. It is also called a transponder.
RFID tags are smart labels that can store a range of information, from serial numbers to several pages of data, including a short description. For a high level of verification and authentication, some RFID tags use cryptographic security features.
The tag is located directly on the object to be identified, and an RFID reader can read the data stored on it from some distance away without direct contact. Unlike barcodes, the line-of-sight of the reader is not needed in RFID tags. Data can be exchanged between the transponder and reader device as long as the RFID tag or transponder remains in the electromagnetic field of the RFID reader/writer.
There are mainly two types of RFID tags:
i. Passive RFID Tag:
Passive RFID tags do not have a power source or batteries. They are powered by the radio signal transmitted from the RFID reader. They do not require a direct line-of-sight to a reader, but a shorter read range and smaller size and weight are preferred. These are the most commonly used tags.
ii. Active RFID Tag:
Active RFID tags have their own power source or battery, and power from the reader is not required. They can transmit data over a longer distance compared to passive tags. These are less common tags.
2. RFID Reader
RFID is the most significant hardware component in RFID technology and acts as the brain of the system. It transmits and receives radio waves for communication with the RFID tag or transponder. It is connected to the antenna and receives data from the RFID tag. It also converts received radio waves into digital data on a computer database.
According to mobility or physical orientation, RFID readers can be classified into two types: mobile RFID readers and fixed RFID readers. Mobile readers are handheld devices flexible for reading RFID tags. Fixed readers stay fixed in one location and are typically mounted on walls or kept on desks or any stationary locations.
3. Antenna
An RFID antenna is a component that regulates the transmission and reception of electromagnetic waves. It is designed to operate at a specific frequency according to the application in which it operates.
RFID antennas are often embedded on the RFID reader and are easily accessible for tags. Depending on the application and operating frequency of the system, the shape and size of antennas may differ.
4. Software
The software controls the RFID reader and RFID tags in RFID technology. RFID technology uses specific types of software programs for RFID operations. The software controls the RFID reader, scanning, and information retrieval from RFID tags. It is used to store data and information on a local computer or to forward it to cloud storage. RFID software is also necessary for erasing and reusing RFID tags.
How Does RFID Works?
The working of RFID technology is based on the principle of inductive coupling, including a source antenna and a receiver antenna. As we know, each RFID tag has a microchip containing a unique identification number, model, manufacturing date, expiry date, access information, short description, etc. The RFID reader accesses such information.
The operation of the RFID process starts with the scanning of an object or item. During scanning, tags are placed near the RFID reader or vice versa. The RFID reader emits electromagnetic signals through its antenna, and small coils embedded on the RFID tag pick up the transmitted signal from the reader. The tag (passive tag) that is nearby the reader is activated by the power of the reader.
Once the tag is activated, it sends radio waves back to the reader using the same antenna coils using the inductive coupling (backscatter coupling) method. The reader picks up the electromagnetic signal of the tag and interprets the frequency and finally translates it into meaningful data using the software.
The working mechanism of the RFID technology is shown in the above figure.
Types of RFID:
Depending upon the operational frequency, there are mainly three types of RFID systems. They are:
- Low Frequency (LF) RFID
- High Frequency (HF) RFID
- Ultra High Frequency (UHF) RFID
Low Frequency (LF) RFID:
The range of operational frequency in the LF RFID system is 30 KHZ-300 KHZ. Typical LF RFID systems work with 125 KHZ or 134 KHZ. There is a shot reading range (about 10 cm) and slow reading speed in this frequency range. Mostly, the LF RFID system is used in the application of access control and animal control.
High Frequency (HF) RFID:
The range of operational frequency in an HF RFID system is 3 MHZ – 30 MHZ. A typical HF RFID system works with 13.56 MHZ with a reading range from 10 cm to 1m. HF RFID systems are Mostly commonly used in ticketing, payments, and data transfer applications.
Ultra High Frequency (UHF) RFID:
The range of operational frequency in the UHF RFID system is 300 MHZ – 3 GHZ. A typical UHF RFID system works with 433 MHZ with a reading range of more than 12 m having a very high data transmission rate. Most RFID projects currently use the UHF RFID systems and hence making it the fastest-growing market segment.
Applications of RFID:
RFID technology is widely used in several commercial and industrial applications to search, identify, track, and communicate with various objects, people, items,s or things. Some common uses of RFID technology are as follows:
- Access control
- Retail sales and supply chain
- Inventory management and control
- Asset Tracking and Equipment tracking
- Vehicle tracking
- People and animal tracking
- Customer service and loss control
- Logistics and Shipping
- Automation on Manufacturing
- Medical and Hospital / Healthcare
- Tollgate system/Electronic road pricing
- Tap-and-go-credit card payment
Advantages of RFID:
RFID Technology provides reliable track and trace services in any environment. It can easily track and provide accurate and real-time information about inventory and product location.
The followings are the main advantages/benefits of RFID technology.
- Cost-effective solution
- Saving time through automation
- Tracking assets and managing inventory
- Improved data accuracy and availability
- Better control of production
- Shorter process
- Enhanced quality and traceability
- Enhancing health and safety
- Increased revenues
- Rapid payback time
Limitations of RFID:
Besides the numerous advantages of RFID technology, there are some limitations/disadvantages. Some of them are as follows:
- The cost of implementation is higher as compared to barcode scanners.
- Implementation can be complex and time-consuming.
- Signals from RFID readers can be blocked by any metal surface and thick materials.
- Accuracy is affected by signal quality (any obstruction could cause an error in data).
- Privacy and security problems with increased use of tags (especially personal information).
