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Radio frequency identification (RFID) is a broad term that covers a suite of automatic identification technologies. RFID systems, broadly speaking, use radio waves to identify objects remotely, so they can be tracked and managed more effectively. The RFID Professional Institute (RFIDPI) covers all types of RFID, including active systems, passive systems and chipless RFID technologies. Exams also have questions related to alternatives to RFID that do not use radio waves, such as QR codes, ultrasound and infrared, because these are used for the same purpose as RFID but are more suitable for some applications.

The Associate Certificate covers all types of RFID and alternative technologies (which may be more suitable for specific applications). The goal of this exam is to demonstrate that the credential holder has an understanding of the different types of RFID and alternative systems, the standards the apply to them, how they work  in the real world and their most common applications.

The Professional Certificate can only be taken by those who have already received the Associate Certificate. It also covers all types of RFID systems and a few alternatives to RFID, but the focus of the Professional Certificate is to show the certificate holder has a good understanding of how to choose the right type of RFID for a specific application, can develop the business case for a solution, can write the application requirements and knows the steps to take to ensure a successful project. Future exams will focus on advanced skills covering specific technologies (see Types of Certifications).

Below is a brief description of the different types of RFID technologies covered in the Associate Certificate Exam. Download the curriculum for more details on exactly what is and is not covered.


See Get Certified for more information on how to prepare for the Institute's certification exams. certification exams:

Active RFID

Active RFID describes an RFID system where both the interrogator and the tag have their own power source. It is called active because the transponder actively broadcasts an RF signal. The tag’s energy source is usually a battery, but can be solar energy or other sources. Among the active systems covered in the exam are those operating at 433 MHz, 900 MHz, 2.45 GHz and ultra wide-band systems that operate between 3 GHz and 10 Ghz.

Passive RFID

Passive RFID describes an RFID system in which the tag does not have the capability of generating an RF field on its own. For passive RFID, communication from the tag to the interrogator is accomplished by modulating the received energy provided by the interrogator. This modulation can be detected in an RF field change by the interrogator.

For inductively coupled systems (usually for frequencies less than 30 MHz), this is called load modulation, as the interrogator sees a load variation of the inductively coupled tag. For wave propagation systems (usually for frequencies greater than 30 MHz), this is called backscatter, as the interrogator sees a variation of the power reflected by the tag due to the modulation. Tags using their own energy source, such as a battery, while maintaining the communication principles of passive RFID are usually called battery-assisted passive (BAP) RFID.

LF (Low Frequency)

Low-frequency tags have a long wave-length and are better able to penetrate certain “conductive” materials (e.g. thin metallic substances, or objects with high-water content, such as fruit or beverages). Typically the LF read range is limited to less than 3 feet, or 1 meter.

ISO 11784/85, ISO 14223 and ISO/IEC 18000-2 are standards for low-frequency RFID systems.

HF (High Frequency)

High-frequency transponders work fairly well on objects made of metal and can work around goods with medium to high water content. Typically, HF RFID systems work in ranges of inches, but they can have a maximum read range of about 3 feet (approximately 1 meter). Typical HF RFID applications include, but are not limited to, tracking library books, patient flow tracking and transit tickets.

ISO/IEC 14443 is the proximity smart card standard for 13.56 MHz. The communication range is usually less than 4 inches (10 centimeters), and applications include access, loyalty and government ID cards, as well as public transport.

ISO/IEC 15693 is the vicinity smart card standard for 13.56 MHz, while GS1 EPCglobal HF and ISO/IEC 18000 are the corresponding standards for item management. The communication range is usually up to 3 feet (1 meter), and applications include ski ticketing and libraries.


Near Field Communication (NFC) is a newer version of RFID based on the ISO/IEC 18092 and ISO/IEC 14443 HF standards. It operates at a maximum range of about 4 inches (10.2 centimeters) and can be set up for one- or two-way communications. NFC is similar to passive RFID due to its ability to read and write to passive smart tags. But in addition to passive read-write capabilities, NFC has two additional modes, both of which involve dynamic, two-way communication: card emulation and peer-to-peer (P2P). With NFC, both devices may initiate communication, wherein the initiator always becomes the interrogator. NFC-enabled mobile phones are such an example. They can behave like a tag, but also as an interrogator since they are able to read tags. In such a way, they can read tag information, store it on the mobile phone and emulate the tag thereafter.

ISO/IEC 18092 is the base standard for NFC. ISO/IEC 21451 is an extension and, as a result, NFC supports P2P communication, which is the key differentiator between NFC and pure passive RFID. But it also supports the reading of smart cards based on ISO/IEC 14443 Type A and Type B, ISO/IEC 15693 and a Japanese industry standard known as Felica. The communication range for all variants is typically less than 10 centimeters.

(Ultra High Frequency)

UHF frequencies typically offer much better read range—up to 20 meters (65.6 feet)—using wave-propagation (depending on the RFID system setup) and can transfer data faster (i.e. read many more tags per second) than low- and high-frequency solutions. However, because UHF radio waves have a shorter wavelength, their signal is more likely to be attenuated (or weakened) or have difficulty passing through metal or water. However, in some special applications, short-range inductive coupling is used for this frequency, thus avoiding the effects of wave attenuation around metal or water, as in HF tags.

Given their high data-transfer rate, UHF RFID tags are well suited for applications which require that many items be read simultaneously, such as boxes of goods as they pass through a dock door into a warehouse or marathon racers as they cross a finish line. Additionally, due to the longer read range of the tags and readers, other common UHF RFID applications include some electronic toll collection and parking access control.

ISO/IEC 18000-63 is the main standard for passive RFID in the UHF frequency band from 860 to 960 MHz. Most applications benefit from the long communication distance of more than 10 meters (32.8 feet) based on wave propagation. Applications using these standards include supply chain management and asset tracking.

Real-Time Location Systems (RTLS)

A real-time location system (RTLS) is typically an active RF technology that can detect a tag's current location and its unique identifier. RTLS solutions are used in a variety of sectors, including, but not limited to, supply chain and logistics, health care, industrial, military, retail and recreation applications.

Increasing the number of interrogators increases location capabilities. Starting with a single interrogator, 1D distance measurements are possible. Three-dimensional (3D) positioning is usually performed with three or more interrogators. RTLS solutions are usually implemented using active RFID tags that beacon—that is, they broadcast a signal at set intervals.

Currently, there are a variety of proprietary systems, some based on one or more of the following: Wi-Fi (IEEE 802.11), ZigBee, infrared, ultrasound, ultrawide-band (UWB) and other various RF technologies.

RFID Alternatives

There are a number of technologies that identify and track objects, but which don't use radio waves. These include infrared, ultrasound and 2D barcode systems. Successful certificate candidates must demonstrate an understanding of these technologies and where they are more appropriate than RFID systems.

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If you are an experienced RFID professional who would like to contribute your expertise to the development of the Institute's examination materials, click here to find out more about the role of SMEs.

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