What is RFID? RFID versus Bar Coding

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1 What is RFID? There are two primary types of RFID that are used in tagging, tracking and finding items. RFID stands for Radio-Frequency Identification. The acronym refers to small electronic devices (labels and tags) that consist of a small computer chip and an antenna. The RFID device serves the same purpose as a bar code or a magnetic strip on the back of a credit card or ATM card; it provides a unique identifier for that object. And, just as a bar code or magnetic strip must be scanned to get the information, the RFID device must be scanned to retrieve the identifying information. RFID versus Bar Coding A significant advantage of RFID devices over the others mentioned above is that the RFID device does not need to be positioned precisely relative to the scanner. We're all familiar with the difficulty that store checkout clerks sometimes have in making sure that a barcode can be read. With RFID, items/tags can be detected 'many at a time' and 'from a distance', whereas bar codes have to be scanned with 'line of sight' from very close proximity. Further, with RFID, items can be FOUND with radio waves, whereas bar codes are essentially useless for finding missing items! UHF RFID Overview UHF RFID technology (Ultra High Frequency) utilizes tags that are powered by radio waves received from portable or detection-zone RFID scanners. A common example of UHF tags are the transportation cards (that hold a $ value available for fares) used by city metro systems. UHF tags do not send a signal unless they are being scanned by a radio wave. In the United States the radio frequency used for item tagging and tracking is 915 MHz. In other countries, the frequency varies between 840 and 955 MHz. UHF tags typically have a detection distance of up to 20' using portable scanners, or up to 40' when using detectionzone antennas. UHF RFID labels generally have a cost of approximately $0.20, depending on the material onto which the label will be placed, and the quantity procured. Active RFID Overview Active RFID technology utilizes tags that have a battery within the tag enclosure, that can be used as a partial or complete source of power for the tag's circuitry and antenna. Some active tags contain replaceable batteries for years of use; others are sealed units. A common example of active tags are the tags used in vehicle for auto-detection when passing through

2 toll booths. Active tags have a typical detection distance up to approximately 300', or greater distances depending on the type of antenna implemented for detecting the tags. Active tags typically have a cost of approximately $15.00 to $50.00, depending on quantity, and depending on special features like motion sensing, tamper detection, temperature sensing, etc. The most common Active RFID frequency is 433 MHz. UHF RFID Tags, Labels and Hardware The antenna and chip are manufactured together as a unit, and are typically referred to as an 'inlay', as pictured below. The copper color above is the antenna, that absorbs radio waves to power the computer chip. The computer ship is the small dot in the middle of the inlay. The computer chip typically includes a random, 24 character # that is 'married' in a database to the ID # of the item to be tagged and tracked. Alternatively, the RFID # in the chip can be 'over-written' with any ID # preferred, typically a # from a host database. The size of the antenna is highly important to the range at which the tag can be detected. An optimal size is approximately 3 7/8 by 5/8. However, a wide range of sizes are available. Tags are available in self-adhesive and hanging styles. The inlay is most often 'built-into' a label or tag. The type of label or tag varies primarily on the type of material onto which the tag is placed. Metal or fluids cause a tag to be unreadable, and therefore the tag must be placed on a foam material to raise the inlay away from the item being tagged, and are generally approximately 1/16 to 1/8 high. If the item to be tagged is not a metal or fluid-containing item, then 'flat' labels can be used, and are less expensive than 'raised' tags. Example RFID UHF tags are shown below:

3 File Folders Non-Metal or Fluid-Containing Items / Containers Tags for Metal or Fluid-Containing Items

4 Hanging Tags RFID ID Cards (people tracking)

5 RFID Scanning Devices There are two primary types of scanners used to emit radio waves to track and find items: portable and 'fixed' scanners. Portable Scanners Portable scanners are most frequently used to inventory items in a storage environment, for example, hospital surgical supplies in a storage room, or, to scan items-in-circulation, for example, file folder records. Portable scanners include a drop-down list of locations (people / places) and can be used to inventory all of the items at each location. This data updates the database to monitor current locations of items, so that when staff search the database, they can determine the correct location of an item. Additionally, the scanner functions similar to a metal detector, enabling a User to enter a missing item #, and the scanner can be pointed around storage areas and work areas. When the needed item is detected, the scanner will beep and highlight the item (the scanner has a list of all missing items), and then will beep faster as you get closer to the item, or more slowly if moving away from the item. Fixed Scanners Whereas portable scanners are handheld and carried by staff to perform RFID functions, Fixed Scanners are placed at strategic 'fixed' locations to track the movement of items and people over time. Fixed scanners can be placed on work surfaces/desks, along hallways, in offices, at office doorways, at entrance/exits, at elevators/stairwells or at any 'choke-point' desired. The scanners can detect items and/or people, and will update the database with 'most recent place detected'.

6 Desktop Detectors Desktop detectors connect to the USB port on a computing device in the work area. The device is 'named' in the database for a location. For example, detector serial # 123 = John Doe's office. Anytime an item is detected by the device, the location of the item is automatically updated in the database to the location associated with the scanner's location. These devices typically send radio waves upward and have a read distance of under 1'. 4 x 4 x 2 Choke-Point Detectors Office, choke-point or doorway detectors are connected to a network via cable or wireless communications to the network server. Choke point antennas can be placed above ceiling tiles, on ceiling tiles, on walls, on any work surface and/or can be mounted in stand-up 'portals' (similar to a doorway at a retail store). Generally, it is ideal for at least two antennas to be at each detection-point, to saturate an area with radio waves. However, single antennas can be used for a detection-point, depending on where the antenna is placed and how items will pass by the antenna. It should be noted that RFID performs best when the radio waves hit the item frontally, versus edge-on. For example, if someone is carrying a file folder on their hip, RFID is more effective 'hitting' the folder from a side-mounted antenna versus a ceiling mounted antenna.

7 Doorway Detectors Doorway detectors are primarily intended to track all the items returning-to or being removedfrom a storage area, such as a file room, evidence room, inventory area, etc. RFID doorways have the ability to track both people and items, including the direction of travel. Alarms and/or video cameras can be connected to RFID doorways to control and monitor access. Security Integration RFID and Security Systems work together to provide solutions that are not available with either RFID or Security Systems alone. Security systems can only trigger based on simple business rules, like no person should be at this location or motion. With RFID, complex business rules can be applied, such as this item with this person is not authorized for this exit. Common security components include alarms, lights, video and alerts.

8 Active RFID Tags, Labels and Hardware RFID Active tags are larger than UHF tags, given that a battery is enclosed. The tags send out a continuous or periodic signal. Active RFID readers (antennas) are available in a variety of styles to read close distances, such as a doorway, or 1,000's of feet, such as on a construction site. The key difference from UHF RFID technology, is that antennas can be place such that all items are detected at all times, such as tracking assets within a hospital. Active RFID is also ideally suited for tracking first responders at a disaster site, or, for personnel mustering. Active Tags Active RFID ID Cards Active RFID Scanners