- 1 What Is RFID?
- 2 How Does An RFID System Work?
- 3 RFID Application
- 4 Radio Frequency Identification Tag (RFID Tag)
- 5 Challenges
- 6 Frequency Types
- 7 Classification of Tags
What Is RFID?
Radio-Frequency Identification (RFID) is the use of radio waves to read and capture data stored on a tag attached to an object. RFID has many benefits over systems that use barcode asset tracking software. The most notable is that the data of the RFID tag can be read outside the line-of-sight, whereas barcodes should be aligned with an optical scanner.
How Does An RFID System Work?
An RFID system is made up of 2 parts: a Tag or Label and a Reader. RFID tags or Labels are embedded with the transmitter and receiver. The RFID component on the tags has 2 parts: a microchip that stores and processes data, and an antenna to receive and transmit a signal. The tag contains the specific serial number for one particular object.
It belongs to a group of technologies referred to as Automatic Identification and Data Capture (AIDC). AIDC methods automatically identify objects, collect information about them, and enter that information directly into computer systems with little or no human intervention.
RFID methods utilize radio waves to accomplish this. At a simple level, RFID systems consist of 3 components: an RFID tag or smart label, an RFID reader, and an antenna. Tags contain an integrated circuit and an antenna, which are used to transmit data to the Reader. Then the reader converts the radio waves to a more usable form of data. The information collected from the tags is transferred through a communications interface to a host computer system, where the data can be stored in a database.
- Inventory Management
- Asset Tracking
- Personnel Tracking
- Controlling Access to Restricted Areas
- ID Badging
- Supply Chain Management
- Counterfeit Prevention (e.g. in the pharmaceutical industry)
Radio Frequency Identification Tag (RFID Tag)
The RFID tag is an electronic tag which exchanges data with an RFID reader through radio waves. Most RFID tags are made up of at least 2 main parts. the first one is an antenna, which receives Radio Frequency (RF) signals. The second one is an Integrated Circuit (IC), which is used for processing and storing data, as well as modulating and demodulating the radio waves, which are received or sent by the antenna. An RFID tag is also called as an RFID chip.
In RFID technology, “tag” also includes labels and cards. This kind of tag depends on the body or object where the tag is attached. RFID systems can operate in either High Frequency (HF), Ultra High Frequency (UHF) or Low Frequency (LF). Thus, tags can also vary in terms of the frequencies on which they operate.
If you’re all in on RFID technology, however, it’s wise to think about these challenges:-
- RFID Can Be More Costly: Whether it be software or hardware, RFID needs more costly equipment that needs to be maintained through the life of the solution. Also, tags, whether they be Active, Passive or Semi-Passive, can set a business back ways. Although costs have fallen with RFID upgrades since the 1970s, businesses are still taking a pass because of the steep costs.
- Trouble With Metals And Liquids: RFID had a difficult relationship working among liquids and metals, as both make it harder to get proper reads on assets. With metal, the problem stems from the radio waves or signals bouncing all over the place. Liquids play disturbance with RFID in that it can absorb signals sent from a tag.
- Tough-To-Grasp Technology: Understanding the different tags and frequencies as well as how to use RFID equipment can be a challenge. Managers need to be up on the technology so that they will train their workers on the ins and outs of RFID and a new workflow.
- The RFID Collision Course: In dealing with RFID technology, workers come across the reader and tag collisions. With reader collision, an employee might come across interference from another reader in the field. Tag collision is a little different, in that employees with readers face problems in reading an abundance of tags at just the once. It happens when more than one tag reflects a signal or a wave, and it also confuses the reader.
Low Frequency (LF) RFID:
These RFID systems operate in the 30 kilohertz to 300-kilohertz range, and have a read range of up to 10 cm. while they have a shorter read range and slower information read rate than alternative technologies, they perform better in the presence of metal or liquids. Common standards for Low-Frequency RFID include ISO 14223 and ISO/IEC 18000-2. Low-frequency tags are used in access control, livestock tracking, and different applications where a short read range is acceptable.
High Frequency (HF) RFID
HF systems operate in the 3 megahertz to 30 megahertz range and provide reading distances of 10 cm to 1 m. Common applications include electronic ticketing, payment, and data transfer. Near Field Communication (NFC), technology is based on HF RFID and has been used for payment cards and hotel key card applications. Different types of smart card and proximity card payment and security systems also use HF technology. Standards include ISO 15693, ECMA-340, ISO/IEC 18092 (for NFC), ISO/IEC 14443A and ISO/IEC 14443 (for MIFARE and different smart card solutions).
Ultra-High Frequency (UHF) RFID
These systems have a frequency range between 300 MHz and 3 GHz, provide read ranges up to 12 m, and have faster data transfer rates. They’re more sensitive to interference from metals, liquids, and electromagnetic signals, however, new design innovations have helped mitigate some of these issues.
UHF tags are less expensive to manufacture, and as such are usually used in retail inventory tracking, pharmaceutical anti-counterfeiting, and other applications where large volumes of tags are needed. The EPCglobal Gen2/ISO 18000-6C standard is a popular global standard for item-level tracking applications.
Classification of Tags
There are 2 different common classifications of tags, depending on how the tag communicates with the reader:
Active RFID tags have their own transmitter and power supply. These are mostly UHF solutions, and read ranges will extend up to 100 meters in some instances. Active tags are usually larger and more expensive than their passive counterparts and are used to track large assets (like vehicles, and machines). Active RFID tags are usually equipped with sensors that measure and transmit temperature, humidity, light, and shock/vibration information for the objects they’re connected to.
There are 2 types of active tags. Transponders only “wake up” and transmit information when they receive a radio wave from a reader. For example, a transponder attached to a vehicle in a toll payment or checkpoint control location would only be active when passing through a specific gate. This helps to conserve battery life.
Beacons emit a signal at a pre-set interval. This type of active tag is used in Real-Time Location Systems for tracking anything from wheelchairs at a hospital to large cargo containers at a shipping dock.
In passive RFID solutions, the reader and reader antenna sends a signal to the tag, and that signal is used to power on the tag and reflect energy back to the reader. There are passive LF, HF, and UHF systems. Read ranges are shorter than with active tags and are restricted by the power of the radio wave reflected back to the reader (commonly referred to as tag backscatter).
Passive tags are usually smaller, less costly, and more flexible than active tags. This means they will be connected or even embedded on a wider form of objects. Passive UHF tags are usually used for item-level tracking of consumer goods and pharmaceuticals.
Battery-Assisted Passive (BAP) RFID
This hybrid type of RFID tag has also emerged. BAP systems, or semi-passive RFID systems, incorporate a power supply into a passive tag configuration. The power source helps to make sure that all of the captured energy from the reader can be used to reflect the signal, which improves read distance and data transfer rates. Unlike active RFID transponders, BAP tags don’t have their own transmitters.
By matching the right type of RFID tag to your application, you can ensure a successful deployment and reap the full advantages of the technology. The various types of RFID technology permit you to get creative to solve real-world business issues.