Wal-Mart RFID Mandate - Background
by Chris Coomber
Although barcodes have been around for quite some time, it wasn’t until the late 80s that they became most popular. In just three years the industry moved from 15,000 suppliers to 75,000.When Wal-Mart™ speaks, suppliers listen.Today due to a Wal-Mart™ RFID mandate the same is occurring. Wal-Mart™ now requests Radio Frequency Identification (RFID) and smart tag technology from their suppliers.RFID HistoryRFID was first introduced during the Second World War as a means for the Allied Forces to detect Friendly or Enemy aircrafts.As a result the term, Transponder (transmit, respond) Signal became widely used. However, instruments using transmitters to power data devices go back to the crystal radio sets.Welcome to the Fascinating World of Smart Tags and RFIDSince the adoption of the barcode into consumer products, there hasn’t been a technology that has been more talked about.RFID, like the barcode, is a great method of capturing data from products such as pallets, totes, bins, corrugated boxes, etc. and sending this data to a destination such as a data base, warehouse management system and/or machine (PLC) control.Advantage of RFID over Barcode Technologyrfid reader technologyThe major reason one would choose RFID over barcode technology is total visibility.Products tagged with RFID inlays are easier to track because once they enter the reader’s range they begin to transmit. This guarantees that you will know when a shipment reaches your location.Such knowledge enables you to get products on the shelves faster, prevent theft and provides better inventory control.Less Expensive in the Long RunAfter they are implemented RFID inlays or smart label technology provide significant cost and time savings over barcode.Rather than scanning each barcode, RFID inlay tags are activated as you get close to them with the RFID reader. This minimizes the considerable cost and time it takes to scan each package with a barcode reader.Dynamic Information Exchangerfid label technologyUnlike barcodes RFID tags allow for dynamic information exchange.A barcode once printed is already obsolete, since the information it contains cannon be changed. With an RFID reader, you can easily rewrite a tag.Active and Passive RFID * Active RFID uses a power source, generally a battery to energize the device and allows it to keep transmitting RF signals. * Passive RFID does not have any powering technology, so that passive device (transponder or tag) relies on the transmitter for its energy.Technology(This document will concentrate on Passive RFID technology): Passive RFID has three (3) major groups or frequency categories: * Low Frequency (LF – 125-134 KHz) * High Frequency (HF – 13.56 MHz) * Ultra High Frequency (UHF – 860-950 MHz)Two higher frequencies at 2.4 GHz and 5.4 GHz exist, however they are not widely used outside of special application. These frequency ranges have advantages, as well as limitations. Distance, interference, transmission speed and metal
Tell others about
this page:
Comments? Questions? Email Here