What Is RFID Chip? An RFID chip is a microchip that uses radio waves to transfer data to a reader. It is the smallest part of an RFID tag yet the most important as it holds the memory for data storage.
The chip is mostly located centrally and surrounded by a coiled wire, known as an antenna. The antenna is responsible for passing radio waves from the chip to the reader. When the tag is powered, it releases electromagnetic waves containing the required information.
RFID chips are used in access management, security access, library systems, time tracking (via electronic logging), identification documents, or medical records.
RFID Chip History
In 1982 Harry Stockman proposed that if every object had a unique identifier, then it would be possible to identify and track specific items using radio waves. This idea would later revolutionize inventory management and identification systems. He published his findings in the technical journal, IEEE Transactions on Microwave Theory and Techniques later that same year.
In 1994 the Auto-ID Lab was established at MIT by Professor Sandy Pentland and Researcher David Brock (who coined the term “RFID”). Their research led to the development of EPCglobal Incorporated – an organization responsible for standardizing RFID technology globally. They created a new numbering system known as EPC (electronic product code). EPC tags were designed to replace barcodes altogether because of their greater range of functionality and improved security features, such as encryption.
By the end of 2000, companies such as Gillette, Procter & Gamble, Motorola, and UPS began trialing RFID technology in their supply chain management setups. In 2002 alone more than 110 million items were tagged for inventory purposes via RFID chips which transmitted data to electronic hand-held devices carried by workers across the warehouse floor.
How Does RFID Chip Work
There are two types of RFID chips (tags) available in the market – active and passive. The difference between them is that active ones have their power sources whereas passive chips get energy from the electromagnetic field of a reader.
The chips consist of unique integrated circuits which can be recognized by radio waves from a reader device. Once powered, the RFID chip will transmit data back to the reader. A reader can transmit radio waves to the tag’s antenna up to 100m away.
RFID chips use certain standards that make them compatible with each other. So, one device will read any standard-compliant tags nearby, no matter which company manufactured it.
RFID Chip Components
An RFID chip consists of an integrated circuit which is typically made using silicon, packaged in a small case with an antenna. This usually resembles a small grain of rice or sand.
There are three components in an RFID device:
- The tag (chip)
- The transponder
- The reader
The tag contains information unique to each item, while the transponder receives energy from the reader unit through electromagnetic induction and transmits it back via radio waves.
The purpose of this electronic transaction between reader and transponder is to identify objects quickly by providing their electronic product code (EPC) number along with other information stored on the tag’s memory chip.
RFID Chip Functionality
An RFID system has two units – one at either end of the communication link.
- The reader is connected to a database through an access point, usually a computer or a programmable logic controller (PLC).
- The chip acts as a transponder, providing information for the reader to store and/or forward as necessary. Communication between reader and transponder is bidirectional: it may be initiated by either side.
Communication from reader unit to transponder occurs via electromagnetic induction using high-frequency radio signals which can penetrate various materials such as plastic, wood, and concrete without any loss of signal intensity. The RFID tag picks up this energy signal and uses it for its internal power supply, thereby increasing its transmission range.
Reader devices form a part of a much larger system that also includes the host computer to which they are attached. In almost all cases, this device is linked using wireless networks to other computers as well as various databases from which it can extract information relevant to its role in an access control network.
For example, if a door reader reads a tag, it not only identifies and authenticates the user but also stores their specific permissions and time signatures. This helps to monitor the human traffic accessing restricted areas. It also guarantees accountability among visitors and staff members.
Types of RFID Chips
There are two different types of RFID chips currently available on the market:
- Silicon Chip. This features a microchip that is encapsulated in a thin layer of epoxy resin and then inserted into a small plastic or glass tag
- Printed Circuit Board (or PCB). This chip contains no electrical parts by design. Instead, it consists of an etched copper antenna combined with an adjoining computer chip.
In some cases, RFID chips can be implemented as either silicon or PCB technology depending on their intended use.
Just like RFID chips, there are different types of RFID readers. For example, a label printer (which may also incorporate an antenna to transmit data) can only print new labels for already identified items. On the other hand, pallet scanners (used for high-speed stock control) look like ceiling-mounted scanners and use long-range antennas to identify tags across wide areas at very high speeds.
RFID Chip Technology
An RFID chip is made out of a thin sheet of glass or Mylar substrate material. It is coated with a special type of magnetic alloy which makes it responsive to very low frequency (VLF) signals in the 13.56 MHz range.
This VLF signal is supplied by most reader devices, which also send the carrier signal via the transmitting antenna to activate the tag’s amplifier circuit. A simple analogy might be that without this activation function, an RFID chip would remain “asleep” until woken up by incoming signals from readers.
RFID Chip Identification
The primary function of identification is authentication: verifying that people and goods are who they claim to be. This process must balance three factors:
- Privacy – ensuring that people cannot be identified unless they have been authorized to access certain resources
- Security – preventing unauthorized people from gaining access
- Convenience – making the process of identification as simple and speedy as possible
RFID chip identification is simple and efficient. Every authorized individual must hold an RFID tag that contains all their details in the chip. For them to be allowed access, an RFID reader will scan the tag, receive data, and compare it with an existing database. If they match, then the individual is allowed access and vice versa.
Each time, the tag’s unique serial number is transmitted to the reader where it is decoded into its original data, translated into human-readable form, and then transmitted to a central database for storage. This process is the same regardless of the type of reader device being used.
RFID Chip Security
When an electromagnetic signal is transmitted, it propagates through space in a wave-like pattern. This concept forms the basis for all wireless communication systems, such as cordless phones, FM radio, cellular telephony, and various other long and short-range communication schemes that we use every day.
The strength and direction of any given signal will vary according to several factors such as:
- The power output of the transmitting antenna
- The distance between transmitter and receiver
- Obstacles such as walls or furniture
- Atmospheric conditions
- Presence of other RF transmitters
Since RFID signals have low power, they face many penetration challenges when encountering sources of interference. As such, they require proximity to the reader for information to be passed (usually up to 100 meters).
Additionally, information stored in the RFID chip is encrypted. As such, cybercriminals can have access to the information unless they steal the specifically assigned RFID reader.
Applications of RFID Chip
RFID chips can be used in many different applications such as:
- Automated customer identification
- Automated toll collection systems
- E-tickets/ electronic boarding passes
- Access control systems
- Robotic guidance systems
- Supply chain management
- Article surveillance/security tagging
RFID operates well in open spaces where there are few physical obstructions to interfere with signal transmission, its performance is not so good when it comes to passing through walls, floors, or even tightly packed goods. This explains why RFID has not replaced barcodes where items are stacked on top of each other.
However, RFID is the best for tagging large objects that are unlikely to move around too much during transportation (such as vehicles). They have better storage than barcodes, which makes them ideal for tagging goods that require a lot of data for identification.
For example, an RFID tag can store data such as the last stock date, the last purchase, the manufacturing date, the batch number among other crucial information. On the contrary, a barcode is prone to environment-related destruction and stores little information. These factors have made RFID technology replace barcodes in many applications.