Welcome to RFID 101
1. What is RFID and How Does it Work?
Have you ever used a key card to enter a building or a hotel room? Ever checked out a book from the library? Or, have you ever paid for something by placing your cellphone or credit / debit card close a contactless payment system? If so, then you already know what RFID is.
RFID, or Radio Frequency IDentification, is a technology that uses radio waves to identify and track objects, people or animals. Think of it as a barcode system like the one they use at your local department store to identify items. When you go to pay for your items, the person working the checkout area uses a scanner to scan the barcode of each item you want to purchase. Using RFID is similar, only RFID is wireless and doesn’t require a direct line of sight between the scanner and the barcode.
2. Parts of an RFID System
An RFID system consists of three main components, a tag (or transponder), an RFID reader (or transceiver) and an antenna used to send and receive signals between the two. Occasionally, an interface may also be used as part of the system.
- Tags are (generally) small devices that store data and are attached to objects.
- Readers are devices that send and receive radio waves to communicate with the tags.
- Antennas help the reader to send and receive signals from the tags.
Now, let’s take a little more of an in-depth look at each of the components:
Tags:
Tags, though generally small, can come in just about any size and shape you can think of (check out or custom RFID solutions to see just what is available –link–). RFID tags are made up an integrated circuit (IC) and an antenna on a substrate. The circuit contains non-volatile memory, which stores data and a unique id number. Tags can be broken down into two types, passive tags and active tags.
- Passive tags, which can be either RO (read only) or RW (read write), don’t have a dedicated power source and lie dormant until they are activated by the radio frequency signal emitted by a reader. Upon being woken or excited by the signal, the tag begins to transmit its data back to the reader.
- Tags typically have an infinite life in terms of being read.
- Tags have finite life in terms of the number of writes. 100k writes is typical.
- Active tags are tags that are battery powered, and do not require the signal from the reader to transmit their data signal. Most active tags are known as TTO (tag talk only), meaning the tag continually transmits its data x number of times per second, and will be read if in range of a reader (which is really more of a listening post).
- Tag life very much depends upon the size of the battery and number of data transmissions, but can be as high as 4 years.
Readers:
Readers are network-connected devices that translate the 0’s and 1’s of tag data into languages like TTL or ASCII bytes that another machine or human can understand.
- Readers can have other functions, like I/O, sound a horn, illuminate a light, etc., or even logic tasks.
- Readers are capable of using many communication protocols including serial (RS232, RS485, RS422), USB, TTL, Wiegand and Ethernet.
Interfaces:
Although readers could output more in-depth language protocols, PLC languages, this would make a single reader significantly more expensive, so it makes more sense to network simple readers together. This process is most often this is handled by an interface, which can manage a network of readers, each reader having its own unique address.
- Typical protocols are specific to a particular PLC manufacturer like Ethernet/IP & DeviceNet (Allen Bradley PLC’s), Profibus & Profinet (Siemens), Modbus RTU and Modbus TCP (Modicon).
- We also offer standard TCPIP Ethernet and serial communications.
3. Types of RFID Systems.
There are three different types of RFID systems in use, and they are based upon the frequency range used by the components. There three types are:
- Low Frequency (LF) products that operate in the 30 KHz – 500 KHz range.
- High Frequency (HF) products that operate in the 3 MHz – 30 MHz range.
- Ultra-High Frequency (UHF) products that operate in the 300 MHz – 960 MHz range.
Each frequency product has its own advantages and disadvantages in terms of read range, data transfer speed and its ability to function with a specific type of material or in a given environment.
RFID, Inc. offers products of all three types.
To do a deep dive into the various frequencies available, please see out Summary of Frequencies page. (Link-blank)
4. How can I determine which frequency is the best option for what I need?
The answer to that question depends primarily on the read range necessary, followed by the type of material the tag will be mounted to or embedded in. The easiest way to figure out what is best for you to contact us using the form below. One of our technical advisors would be happy to work with you on finding the perfect RFID solution.
Have a question about our products?
Contact us today.
To contact RFID, Inc. simply fill out the form below. You are also welcome to give us a call directly at the number listed.
RFID, Inc.
14190 E. Jewell Avenue
Suite 4 Aurora, CO 80012
Phone.
(303) 366-1234
Email.
info@rfidinc-com.preview-domain.com
