RFID Technology Basics

What is RFID technology?

Radio Frequency Identification (RFID) is a contactless technology that uses electromagnetic waves to wirelessly transfer a digital ID and additional data between an RFID tag and a reader. This technology enables businesses, organizations, and consumers to assign a unique digital identity—often referred to as a digital twin—to physical objects. This unique ID allows for easy identification, authentication, tracking, and interaction with the objects in real-time.

Unlike other auto-ID technologies, such as optical QR codes, RFID does not require a direct line of sight for data transfer. By integrating RFID technology into their operations, businesses can streamline their processes, enhance operational visibility, and improve overall efficiency, allowing for better management and tracking of assets, inventory, and other items.

Components of an RFID system, how RFID works?

An RFID system is a comprehensive setup that uses wireless radio frequency technology to identify, track, and manage objects. While RFID tags are an integral part of the system, the RFID system also includes other essential components like readers, antennas, and the host system. Together, these elements form a complete solution for businesses looking to address specific operational challenges.

Reader: The reader is a core component of the RFID system, responsible for transmitting radio frequency (RF) energy to activate RFID tags. It also receives and decodes the data sent by the tags. Typically, an RFID reader consists of an RF module, a microprocessor, and an interface that connects the reader to the host system, enabling data transfer and further processing.
Antenna: The antenna in an RFID system is responsible for transmitting RF energy from the reader to the tag and receiving the data sent by the tag. Antennas come in various shapes and sizes to suit different applications, and they can either be integrated into the reader or positioned as a separate component.
Tag: The RFID tag is attached to the item being tracked and is responsible for storing and transmitting the data associated with that item. It contains a microchip and an antenna (don’t confuse it with the reader’s antenna), which work together to enable communication with the reader. RFID tags can be either passive, drawing energy from the reader to transmit data, or active, with their own internal power source to enable longer-range communication.
Host System: The host system refers to the software and hardware infrastructure that controls and manages the RFID system. It typically includes a computer, server, or cloud-based platform running RFID software that communicates with the readers and processes the data collected from the tags. The host system ensures that all RFID data is organized, analyzed, and integrated into the broader business operations.

RFID works by using radio waves to communicate between RFID tags and readers. The RFID reader emits a radio frequency signal through its antenna, which is modulated with data and sent out into the surrounding area. When an RFID tag comes within range of the signal, it captures the energy from the reader’s radio waves. If the tag is passive, it uses this energy to activate and transmit its data back to the reader. If the tag is active, it uses its own power source to send the data.

Once the reader receives the data, it decodes it and sends it to the host system for processing. The host system then integrates the data into business operations, enabling real-time tracking and management of the tagged objects. This process allows RFID to identify and track items wirelessly, without the need for direct line-of-sight scanning, making it a highly efficient solution for a variety of applications.

Passive RFID tags vs Active RFID tags

RFID tags are a crucial component of RFID technology, enabling the wireless tracking and identification of objects. These tags come in two primary types: passive and active, each offering distinct benefits depending on the specific application requirements.

Passive RFID Tags:
Passive RFID tags do not have their own power source and instead rely on energy from the RFID reader to activate and transmit data. They are the most widely used type of RFID tag, primarily because of their lower cost compared to active RFID tags. Common applications for passive RFID tags include retail inventory management, asset tracking, and access control systems. Additionally, passive tags are often used in embedded solutions to provide a unique identifier for products throughout their lifecycle.

Active RFID Tags:
Active RFID tags come equipped with an internal power source, typically a battery, which allows them to transmit data over much greater distances. These tags are often chosen for use in applications like supply chain management and long-range asset tracking, where extended range is essential. However, they tend to be more expensive than passive RFID tags due to their built-in power supply.

Aside from these two main types, there are also hybrid RFID tags, such as semi-passive and battery-assisted passive (BAP) RFID tags. These variants combine the features of both passive and active tags, offering unique advantages for specific use cases.

	Passive	Active
Battery	No	Yes
Reading range	Up to 20m	Up to 100m
Memory, functions	Memory limited to RFID chip Reader logs reads	May have larger memory May self log data to memory
Cost	Low	High

The decision between passive and active RFID tags largely depends on the specific requirements of the application. If your application demands a cost-effective solution with compact size and long lifespan, passive RFID tags are likely the better option. In contrast, active RFID tags are more suitable for applications requiring long-range communication and continuous data transmission. Since passive RFID tags dominate the market due to their affordability and versatility, our company also focuses primarily on providing passive RFID tag solutions.

Barcode vs RFID

Barcode

Barcode has been a universal fundamental element of all industrial products since the 1970s. It remains and should last for the next 1-2 decades in global industries, although some new technologies like RFID are emerging, it benefits from the significant features of barcode technology:

Lowest cost and based on well build barcode infrastructure under international standard,
Fast one by one reading, billions of products scanned at the checkout counter,
Easily accessible cyber-physical data connection plays a crucial role in collaborating with the back IT management system,
Easy to attach on any product, no doubt, be an essential element of the management system.

Industries and retailer businesses are recently facing a comprehensive challenge caused by competition of similar product global purchasing, labor and production cost continually rising, flexibility requirement ever-increasing from the market. All facts had been leading to tighter profit margins, more efficient industrial processes. Most successful business owners were mindful of a promotive solution to improve inventory control, asset tracking, and supply chain management, and auto-industry as well.

RFID

With our experience in the global Auto-ID industry during the recent two decades, radio frequency identification technology is no doubt the best-upgraded version of barcode technology. And sure to be wildly applied in all industries production management, chain supplier, and logistics management in the coming years to meet the trend of new era global industry regarding the characteristics of RFID as below.

Group multiple reading (bulk reading) instead of single reading by barcode,
Omni-direction and penetrating reading, the RFID tag can be read even inside a container.
50 to 70 times faster than barcode data collection
Convey data capacity several times more significant than a barcode, with secure data protection.
RFID data deletable after a whole process cycle,
save a lot of labor work to move packages by a designed auto data collection with an array of RFID antennas and readers, no need to open the package for checking.
integrating RFID data algorithms in inventory management systems, for accurate retail warehouse inventory realized with RFID handsets, or some RFID fixed on-site readers, approved in many apparel retail management systems.

Besides RFID in industry and logistic applications, billions of item-level RFID tags used on high value-added, high accuracy, and efficient logistics requiring products, like clothing, cosmetics, medicine, alcohol, fresh foods, and military products in the recent 5 years.

The prime advantages of RFID on item level

through an RFID tunnel or an RFID chamber, RFID item tags in a container can be read at high speed without opening the package. A sophisticated allocation package can ensure a transparent and efficient operation.
securely encrypted RFID data to protect the business information and prohibit most of the counterfeit products into the supplier chain.
A tamper-evident seal RFID tag gets fake products by an authorization APP operated by end-users or distributors.
Brand owner published APP allows end consumers to get online support directly with operation videos and instructions with NFC enabled mobile devices, which cover most of the market. All tracking information found through mobile phones. After-sales service, re-ordering, quality feedback, and tracing becomes much more straightforward.
RFID technology can realize the complicated management to avoid those lost in barcode systems, including cross-boundary selling, lack of stock and overstock, vicarious inventory, overdue orders.
brand owners are very interested in Dual-Frequency RFID (both UHF and NFC work in the same microchip) for expensive alcohol or pharmacy products. It can work both long-range readings around 8 meters and can be read by NFC mobile phone simultaneously, fulfill both fast logistics and chain supply, as well as NFC’s supported functions at the end-customer side.
A proper design whole processes management by RFID can cover the whole history of the product life, beginning from the production management, supply chain, distribution, verification before purchase, and customer’s after-sales service, as well ax re-ordering.

Additional subscriptions before RFID application

RFID is probably an updated version of barcode, and it means if you have successful experience of most management systems based on barcodes, RFID offers a smooth transition from existing data-based systems to achieve the targeted performance. In other words, it is better to establish an RFID system based on industry-standard 3.0, cooperating with RFID middleware and hardware to achieve the desired goal.
To fulfill an efficient inventory of mass products, a expect RFID regular rate up to 100% on-site, client need to provide the details of the product with the package (especially the high humidity or and metal include), and to stack way on a pallet. We design and develop a customized RFID tag and read facilities to work together and get rid of interference caused by RFID sensitivity of the environment.
RFID applications must work with regulated and managed policies in standardized operations toward automatic in and out data collection.
RFID project investment is still relatively expensive, although RFID tags and readers have been 10 times cheaper than 10 years ago. An excellent ROI (Return On Investment) can achieve long-term consideration instead of some risk caused by cheap parts.

What is the difference between RFID and NFC ?

RFID and NFC are two very similar wireless communication technologies, and they are used in many applications. RFID vs NFC: what is the difference between RFID and NFC?

RFID, radio frequency identification, is a general term for all contactless communication, and NFC is a subset of RFID. It is a wireless technology mainly used to transmit data. Its main purpose is to automatically trace and track the RFID tags attached to objects. RFID frequency range includes: low frequency (LF), high frequency (HF) and ultra high frequency (UHF). Reading range of LF and HF systems is usually only several centimeters. While, reading distance of UHF tag is usually more than one meter.

NFC, near field communication, based on RFID protocol, with short reading distance. The main difference with RFID is that the NFC device can not only act as a reader, but also as a tag in card emulation mode. And in peer-to-peer mode, information can also be transferred between two NFC devices. NFC reading distance usually very short, no more than 5cm. It is mostly used for cashless payment, membership management, transportation, access control, business process management, labor management and e-government.

RFID (Radio Frequency Identification)	NFC (Near Field Communication)
RFID is item centirc, NFC is user centric, and NFC is a subset of RFID.
* Invented in the 1980’s	* Invented in 2002
* Improves upon printed barcodes Does not require line of sight Increased read range Can be read quickly in batches	* Improves upon QR codes Does not require line of sight Increased security Added intelligence
* Stores and transmits simple ID’s	* Stores and transmits multiple data types
* Inventory tracking through the supply chain	* Adds utility to products during use
* Loss prevention	* Product authentication
Time to connect: <1ms	Time to connect: <1ms
Read Range: (passive) 1m-10m (active) 10m-100m	Read Range: 0cm-5cm
Tag Reader: Fixed infrastructure reader Handheld reader	Tag Reader: Smartphone
Tag Price: <$0.10	Tag Price: >$0.10
What can RFID be used for?	What can NFC be used for?
* Track and trace inventory management (Locate items within a space) * Loss prevention (Alerts stolen products) * Access control * Race timing (Provides a seamless race-day experience) * Attendee tracking (Eliminates registration lines) * Pet / livestock identification	* Content Channel (Embedded experiences, exclusive content, messaging, product gamification) * Customer acquisition across sales channels (Product registration, store check-in) * Product authentication / Brand protection * Mobile payments (Upsell experience, Resell experience)

How to select the right RFID tag?

Selecting a right RFID tag is not easy. It require fully understand the relationship between tags, read / write devices, and systems, the purpose of RFID tags application. RFID tag performance is impacted by working environment. Some factors should be considered to select proper RFID tags, such as the tag type, the operating frequency, the object material which the tag to be attached, installation, reading range, reading rate, tag specification, working environment, variable data processing, cost, etc.

1, Frequency

Passive RFID tag has three kinds of frequency, LF, HF and UHF. Selecting the right frequency depends on some factors such as read range requirements, data read rate, security level, cost, etc. Applications like access control and payment systems require a short read range, and typically use HF tags. UHF tags are ideal for applications requiring long read range.

LF (Low Frequency): For special application environment and there is no requirement for reading distance, LF can be considered. Such as animal management, etc. Since LF transfers data slowly, small limited storage memory, poor flexibility, most of the low-frequency is unwritable, weak security, and the hundreds of coil wires has causes the costs more, and it is not easy to make flexible labels. So the market share is getting less and less.
HF (High Frequency): Readable and writable. HF is selected for applications with more capacity and high encryption level, such as payment, ticketing, security access control, membership management, identification applications,
UHF (Ultra High Frequency): Readable and writable, long reading distance up to 10 meters, anti-collision, bulk rain UHF tagsreading, fast transmission speed, 1,000 tags (EPC C1G2) are full readable at a time. Linear and circular polarization antenna design, which can meet the requirements of different applications, low cost, easy operation, and wide range of applications. The-state-of-the-art IoT is already adopted UHF technology, such as in the supply chain, warehouse management applications, logistics, retail and other management.

2, Environmental Factors

The environmental conditions are the main considerations for RFID tags selection. The environmental conditions that affect the performance of the tags are mainly temperature, humidity, indoor or outdoor use, compression and anti-collision, metal, oil, acid, and alkali chemicals.

Such as the label embedded in the product may encounter high temperature and strong pressure during the product manufacturing processer. For outdoor applications, UV, rain, and temperature on label life should be considered.

3, Tag Type

The factors of the choice tag type are the reading range, application environment, cost, size, material, installation, and application in special industries.

The RFID tag encapsulations are available in PVC, PET, PPS, nylon, ABS, ceramic, silicone, inlay, RF-4, paper.

RFID flexible tag: If you need long read distances, and normal applications and storage environments, economic cost, generally PET or Paper flexible UHF tags are best choice.

Involving the metal and harsh working environment, such as oil, chemical, high and low temperature, rigid hard-enclosed plastic housing RFID tag, ceramic RFID tag is best for selection.

LF, HF laminated hard PVC RFID tag is normally used for common application environment and cost-effective requirements.

There are also special application such as waste management, laundry industry, and pharmaceuticals.

4, Reading Direction

Tag performance is affected by the orientation of the antenna of the reading device. When the plane of the tag and the plane of the antenna are parallel to each other, the optimal tag orientation appears. In this direction, the tag will get the maximum power. As the tag rotates, it presents a smaller effective area for incoming radio waves, so less power is collected. The tag read range decreases as the collection power decreases.

Most passive UHF tags have a dipole antenna, with zero points at the north and south poles. Such tags cannot be read when the magnetic pole axis on the tag antenna is perpendicular to the plane of the interrogator antenna. The best effect appears when the RFID tag antenna coil parallel to the coil of the reader.

5, RFID Tag Placement

Placement of the RFID tag on the object will affect the tag’s performance. Especially the effect of moisture and metal on the performance of the tag is obvious. For these factors, HUAYUAN has special solutions when designing and selecting tags, such as wine, shampoo, beverage, many drugs in liquid form, and liquid food in bottles.

To read a UHF label attached to a package containing an aqueous liquid, there must be a certain space between the label and the liquid bottle. The RFID label can be designed according to the actual packaging so that its antenna always away from the liquid. Such as HUAYUAN RFID tag for liquid tracking.

6, RFID Tag Installation

The installation methods of RFID tag are self-adhesive, screw, rivet, hanging, magnet adsorption. This depends on the actual situation of the managed requirement. Permanently fixed or transferable require or not.

For the self-adhesive tag, you also need to know the material of the object, which the tag will be stuck on in order to determine what type of glue to use.

The installation of on metal RFID tag could be by rivets, screws or magnets.

Types of memory in Gen 2 UHF RFID tags

Gen 2 UHF RFID tags consist of an antenna and a chip, technically known as an integrated circuit (IC). Here, we will explore the four memory banks within the IC of a UHF RFID tag, detailing when to use each. The four types of memory in Gen 2 tags are:

Reserved Memory
EPC Memory
TID Memory
User Memory

More information about each RFID tag memory bank.

Reserved Memory

Key Function: Stores Access and Kill Passcodes
Writable: Yes, for updating passcodes

Reserved memory contains the kill password and the access password, each 32 bits long. The kill password is designed to permanently disable the tag (though it is rarely utilized), while the access password controls the write permissions of the tag. This memory bank is only writable when you need to set specific passwords. Generally, it is not used unless your application requires heightened security, as it cannot store any data beyond these two codes.

EPC Memory

Key Function: Primary Writable Memory
Writable: Yes

EPC memory holds the Electronic Product Code (EPC) and provides a minimum of 96 bits of writable memory. This memory bank is the most commonly used in applications requiring 96 bits of data. Some tags allow the allocation of additional bits to EPC memory from the user memory. EPC memory serves as the first writable memory bank.

TID Memory

Key Function: Tag’s Unique ID
Writable: No

TID memory is reserved for storing the unique identification number assigned to the tag by the manufacturer during production. This portion of memory is typically read-only and cannot be modified.

User Memory

Key Function: Additional Writable Memory
Writable: Yes

User memory provides extra writable space for users who need more than what the EPC section can offer. While there is no standardized amount of writable memory across tags, extended user memory typically ranges up to 512 bits, with some high-capacity tags offering up to 4K or 8K bytes. This serves as the second writable memory bank for Gen 2 ICs.

When starting your application and selecting an RFID tag, in order to know about how much memory is on each tag’s IC, you can check the specifications page on each tag’s data sheet. Or take a look at our UHF IC RFID comparison guide.

Manufacturer	IC	EPC (bits)	User (bits)	Read Sensitivity (dBm)
NXP	UCODE 8	128	0	-23
NXP	UCODE 9	96	0	-24
NXP	UCODE 9xm	128/256/496	752/624/384	-24
Impinj	Monza 4E	496	128	-19.5
Impinj	Monza 4QT	128	512	-19.5
Impinj	Monza R6	96	0	-22.1
Impinj	Monza R6-P	96/128	32	-22.1
Impinj	M730	128	0	-24
Impinj	M750	96	32	-24
Impinj	M781	128	512	-23.5
Impinj	M830	128	0	-25.5
Alien	Higgs 9	96	668	-20
FUDAN	FM13UF011E	96/496	512/112	-24
FUDAN	FM13UF0051E	128	32	-24
Quanray	Qstar-7U	128	128	-24