Frequently Asked RFID Questions
Automatic identification, or Auto ID for short, is the methods and means to automatically identify objects, capture data about those objects, and pass that data to a computer system. This all happens without any human interaction. The goals of these systems are to reduce human input error and increase efficiency in automated systems. There are a handful of different technologies that fall under the auto-ID umbrella, such as bar codes, smart cards, voice recognition, some biometric technologies (retinal scans, for instance), optical character recognition (OCR) and radio frequency identification (RFID).
What is RFID?
Radio frequency identification, or RFID, is the wireless method of transmitting data between a transponder (tag) and an interrogator (reader) for the purpose of automatically identifying and tracking objects. RFID can be passive, in which the tag harvests power from the RF field generated by the reader, or active, where the tag has its own power source and actively transmits back to the reader.
Does RFID have advantages over barcodes?
RFID has several distinct advantages over using barcode technology:
- RFID does not require line of sight to read tags, and can be read through materials like plastic and wood.
- RFID can uniquely identify billions of objects with no overlap, barcodes typically identify only the type of object.
- RFID tags can be read from very long distances, 30 feet or more, compared to a few feet for barcodes.
- Many RFID tags can be read at once, making them very useful for inventory purposes.
In what ways are companies using RFID today?
Thousands of companies around the world use RFID today to improve internal efficiencies. RFID is used to automatically track inventory in warehouses and retail stores; it is used to authenticate ink in printers; to verify that medical consumables are genuine and unused; to track people and workers in hazardous places, and IT equipment in offices. RFID is used in places where unique objects need to be identified fast and accurately, which can be just about anywhere (See Case Studies for more examples of how RFID is benefiting companies today.)
How does an RFID system work?
An RFID system is typically made up of three components: an interrogator (or reader,) an antenna connected to the reader, and a transponder (or tag.) Most systems require that the reader transmit a signal first, which is radiated by the antenna. The tag, which is made up of a small microchip and an antenna, is woken up by the reader’s signal and interprets what it is saying. Based on what the tag receives, it transmits its own signal back to the reader, which is usually an ID or some other stored information. In passive RFID, the tag does not have its own power source, so it harvests the energy created by the reader, then uses a technique called backscattering to send information back. In Active RFID systems, the transponder has its own power source and can transmit data back to the reader.
What is the difference between low-, high-, and ultra-high frequencies?
Just as your radio tunes in to different frequencies to hear different channels, RFID tags and readers have to be tuned to the same frequency to communicate. RFID systems use many different frequencies, but generally the most common are low-frequency (around 125 KHz), high-frequency (13.56 MHz) and ultra-high-frequency or UHF (860-960 MHz). Microwave (2.45 GHz) is also used in some applications. Radio waves behave differently at different frequencies, so you have to choose the right frequency for the right application.
How do I know which frequency is right for my application?
Each RFID frequency has its own benefits, which make it more useful for certain applications than others. Low frequency RFID has very short detection range, but the best penetration through water. These tags are commonly used for animal tracking or tagging produce. High frequency tags have better detection range, and can store a lot of information. These tags are used to authenticate consumables such as printer ink, or are used in credit card and secure credentials because they can store encrypted information. Ultra high frequency has the longest range and many tags can be read simultaneously. UHF is well suited for inventory management or detecting people and objects from far away.
Do all countries use the same frequencies?
No. Which frequencies are allowed for use various depending on the country you are in. Some RFID frequencies are more standardized than others. For example, Low frequency is typically used between 125-134KHz, and High Frequency is almost always 13.56MHz. Ultra-high frequency RFID is newer, so there is more variability. Each country allots part of the frequency spectrum between 860-960MHz for RFID. For example, in North America they use 902-928MHz, but Europe uses 865-868MHz. The frequency band and regulations governing the use of these bands can be difficult to navigate, but we know the way through. See our Regulatory Testing services for more information.
Are there any standards for RFID?
Yes. The International Organization for Standardization (ISO) has been making RFID standards for more than 20 years. ISO 15693 and ISO 14443 are well-established HF standards. The EPCglobal Class 1 Gen 2 standard has been adopted as a global standard (ISO 18000-6C), and ISO 18000-7 is an international standard for active tags operating at 433 MHz.
What is EPC Class 1 Gen 2 (C1G2)?
Gen 2 is the shorthand name given to EPCglobal’s second-generation EPC air-interface protocol (the language tags and readers use to communicate). It was designed to work internationally and has other enhancements, such as a dense reader mode of operation, which prevents readers from interfering with one another when many are used in close proximity to one another. EPCGlobal is now part of the GS1 standards organization.
What’s the difference between ISO and EPC?
The Electronic Product Code is a standard created by EPCglobal, designed as a global standard for use in many industries. In July 2006, the EPC Gen 2 protocol was approved and adopted by the International Standards Organization as the ISO 18000-6C standard. ISO has created many standards for RFID that deal with both the air-interface protocol and applications for RFID. EPC deals with more than just how tags and readers communicate. EPCglobal has created a suite of standards to govern how EPC data is shared among companies and other organizations.
What is ISO 18000-6?
ISO 18000-6 is an international standard governing the way tags and readers communicate in the UHF spectrum. There are currently three versions: 18000-6A, 18000-6B and 18000-6C. Of these, 18000-6C is by far the most commonly used.
Other RFID Issues
Are there any health risks associated with RFID and radio waves?
Some have questioned whether electromagnetic fields (EMF) generated by power lines, mobile phones, WLANs, RFID readers and other wireless devices may be harmful to human health. There have been a large body of studies conducted, some by the World Health Organization, that have shown that EMF exposure below the limits recommended in internationally adopted guidelines has not revealed any known negative health effects. To ensure a uniform benchmark for compliance, EPCglobal recommends adhering to the human exposure limits for EMF as developed by the International Consortium on Non-Ionizing Radiation Protection (ICNIRP) and recommended by the WHO.
How can RFID improve worker safety?
RFID can be used to prevent unauthorized workers from using dangerous machines, or to track personnel in hazardous areas. When using machinery, a worker may have to present the proper RFID credentials, which show that the worker is trained and authorized to use that machine, or it will not turn on. In hazardous areas, RFID can monitor workers in safe zones and send alerts if they are left. RFID readers can also be placed on large outdoor machines like bulldozers so they can detect works that the driver cannot see. If the reader sees a worker, an alert is sent to the driver instantly.
How can RFID improve promotional and marketing incentives?
Companies such as Kimberly-Clark, Procter & Gamble and many others are using RFID to track the location of promotional displays in the supply chain and within RFID-enabled stores. By knowing that promotional displays are not where they need to be, these companies can proactively work with retailers to get displays out, thereby increasing sales. RFID also has the potential to improve in-store marketing by enabling retailers to advertise to shoppers depending on where they are in the store. Shopping carts with smart terminals containing an RFID reader can read tags on shelves and, say, promote beer on sale when the consumer is in front of the beer section in the store. In the future, when more individual products are tagged, some envision readers in carts identifying products and pitching related items. For instance, when a customer places lettuce in a cart, the smart terminal might flash an ad for salad dressing.