What Is RFID?
Radio Frequency IDentification is a technology that allows almost any object to be wirelessly identified using data transmitted via radio waves.
Benefits of RFID
The ability to identify and track individual items, as well as crates of items, without line of sight can be an advantage for many companies across almost any vertical. For example, if a company has 5,000 identical plastic crates, an RFID tag can be placed on each one in order to recognize crate 1,948 from crate 3,097 without requiring line of sight. Identifying these crates can be crucial to the company’s bottom line when one is carrying valuable merchandise or a customer’s order. That company needs to not only keep track of that merchandise or order, but also potentially the crate itself, if it is one of the company’s assets. RFID can be used to locate and track these assets. Below are some additional benefits of using RFID:
- RFID doesn’t need line of sight
- RFID tags are able to be rewritten and reused
- RFID tags can be extremely durable against impact and environmental factors
- RFID tag data is encrypted and can also be locked for extra security
- RFID tags can hold more data than other types of tags or labels
- RFID readers can read hundreds of tags within seconds
- RFID tags can have information printed on them like instructions, barcodes, or company names
- RFID systems can be integrated with other internal systems or processes
What Makes Up an RFID System?
Several pieces of hardware are involved in creating a working RFID system. If a system is set up properly with the correct equipment and thoroughly tested and tuned, then it should be able to read moving or stationary tags with near 100% efficiency. Below are the different parts that make up a UHF RFID system.
Reader – An RFID reader is the “brain” of the system. Readers can be programmed to only read certain RFID tags, read tags at a certain time, read tags once in inventory mode, or read tags over and over to gauge specific information. Readers vary from around a few hundred dollars for a simple reader/writer to over several thousand dollars for a complex, high-performance reader.
Antenna – RFID antennas actually send the RF energy to the RFID tags in order to energize them and then listen to receive the tag’s reply. They are connected to the RFID reader using a coaxial cable, and function like a reader’s “arm” to send and receive information.
Tags – RFID tags are placed on objects and, unless they are active RFID tags, wait to be read or interrogated by the reader. Tags have one or more memory banks to store various information and unique identifiers.
Cables – Coaxial cables connect the reader and antenna allowing the reader to send commands via RF energy to the antenna. RFID cables vary in terms of connectors, length, and insulation rating – each which is important to understand for an application’s success.
Auxiliary Items – Depending on how complex an RFID system is, additional items can be added for ease-of-use or additional functionality. Those items include antenna mounting brackets, RFID printers, GPIO adapters, and portals.
Software – Some type of software is necessary in any RFID system. Whether it is just firmware and a basic software program, or firmware, middleware, and complex software – some type of software must be present in order for the hardware to perform even basic functions.
For more information about RFID and RFID systems, checkout our Beginner’s Guide to RFID.
Breaking Down RFID – Frequency Types
RFID tags communicate using electromagnetic waves and operate between 125 kHz and 960 MHz. Below is a breakdown of the different frequencies and how they are typically used.
Low Frequency – 125 – 134 kHz – Low Frequency (LF) is used for applications such as animal tracking. These tags are small and work well with tracking animals because water has almost no effect on their read range. The read range for low frequency is between contact to 10 centimeters in length.
High Frequency – 13.56 MHz – High Frequency (HF) systems have a read range from 1 centimeter to up to 1 meter in length. Near-Field Communication (NFC) is part of this frequency and is used in applications like smart posters, movie kiosks, and other short range applications such as transit ticketing systems.
Ultra-High Frequency – 865 – 960 MHz –this frequency (UHF RFID) makes up the bulk of RFID applications. The read range for passive UHF tags is from a few centimeters for small tags, to up to 35 feet in large tags. This frequency is often seen in tolling applications, asset tracking, race timing, and tool tracking.
Active RFID :
Active RFID – 433 MHz or 915 MHz – Active RFID tags contain a battery to boost their read range to anywhere between 100 and 300 meters in length. These tags can be read from a long distance away, but the battery life is only about 3-5 years and the tags are larger, bulkier, and higher-cost than their passive counterparts. Active tags are seen in construction yard applications (due to the long read range) and just about any system that requires real-time location (due to the continuous beaconing of the tags).
For more information on the different frequency types and their applications, checkout our eBook “Types of RFID and How They Are Used”.
What RFID Isn’t
- RFID technology isn’t an all-knowing, all-seeing, limitless technology.
- RFID tags do not store immense amounts of data – most are designed to hold a number for identification. While some tags can store more data in the user memory section, accessing that additional data slows down read time.
- RFID tags can’t be read from everywhere. Most UHF RFID tags, on average, can only read 14 – 20 feet depending on the frequency and size. The tags used in large outdoor applications CAN be read from up to 500 feet, but they are active RFID tags (which means they contain batteries and on average only live 3-5 years) and are pretty big – typically larger, heavier, and a good deal more expensive than passive tags.
- An RFID system isn’t cheap – most systems average in cost from a few hundred dollars for a small reader/writer and a few tags to over several thousands of dollars for a single read zone with a reader, a few antennas, and tags.
- RFID tags are not insecure or unprotected – most tags come with a security protocol that can be enhanced with software or the tag can be locked from being read with a passcode.
- Just like you can’t track down your “chipped” animal when it is lost (LF RFID), you can’t track tagged objects unless there is RFID hardware in the read area. If hardware is setup throughout a building, you can track a tagged object in the building, even (with the correct setup) identifying the room in which it is located. But, once the object leaves the building and the read area, the tag is no longer traceable unless introduced back into the read area.
RFID Around Me
Most people don’t realize how many times they have used RFID or driven past an RFID-enabled device on a daily or weekly basis. Access cards and key fobs to enter buildings, automated toll collection on highways, truck weigh stations, movie kiosks, and credit card chip readers are all around us and all use RFID technology – and that is just the beginning. Hotels are now using RFID for room keys, hospitals are using it for inventory control, warehouses for asset management, and construction sites for tool tracking; the possibilities are nearly infinite.
While most of those applications have been around a few years, more pop up every day. Whether tags are in wristbands at popular music festivals, in golf balls at driving ranges, interactive children’s toys, or inside a beer mug at a local bar (think self-serve beer) – the fact is, RFID technology is growing rapidly and is powering the Internet of Things (IoT). Endless applications are being brought to life every day that are quickly changing people’s questions from “What is RFID?” to “What can I do with RFID?”.