Introduction
The first use of Radio Frequency Identification (RFID) was documented in the 1940’s by the British Royal Air Force to identify aircraft in World War II and was part of the refinement of radar. During the 1960’s RFID was first considered as a tracking solution in the commercial world. The first applications involving RFID were developed over the next twenty years. These commercial applications were concerned with identifying an item inside a single location.
The latest attempt to commercialize the use of RFID started in 1998, when researchers at the Massachusetts Institute of Technology (MIT) Auto-ID Center began to research new ways to track and identify objects as they moved between physical locations. This research centered on radio frequency technology and how information that is held on tags can be effectively scanned and shared in real time.
Mechanics Of RFID
The basic principle of RFID is identifying an object using a radio frequency transmission. The technology can be used to identify, track, sort or detect a wide variety of objects. Communication takes place between a reader or interrogator and a transponder or tag. Tags can either be active, which means it is powered by battery, or passive, which is powered by the reader field. The communication frequencies used depends to a large extent on the application, and range from 125KHz to 2.45 GHz. Regulations are imposed by most countries to control emissions and prevent interference with other industrial, scientific or medical equipment.
In a typical system tags are attached to objects. Each tag has some internal memory which it stores information about the object, such as its unique ID number, or details including date of manufacture and item information. When a tag passes through a field generated by a reader, it transmits this information back which identifies the object. Until recently the focus of RFID technology was mainly on tags and readers, which were being used in systems where relatively low volumes of data are involved. This is now changing as RFID in the supply chain is expected to generate huge volumes of data, which will have to be filtered and routed to ERP or Warehouse Management systems.
Electronic Product Code (EPC)
Electronic Product Code is the emerging RFID standard developed by the MIT AutoID center. It is the RFID version of the UPC barcode standard. Like UPC, EPC is intended to be used for specific product identification as well as case and pallet identification. However, EPC goes beyond UPC by not only identifying the item, but also providing access to additional data about the origin and history of the specific batches or serial numbers. The EPC tag itself identifies the manufacturer, product, version, and serial number.
Benefits Of RFID
Supply chain management is investing in RFID as it can give them advantages in visibility of their products through the supply chain. The benefits are seen as improving on other methods of visibility such as EDI, bar coding and Advance Ship Notifications (ASN). Other benefits of RFID can be seen outside of normal supply chain such as a reduction in theft from the store, transport or storage, and a deterrent to increasing product counterfeiting. Both of these issues are costing companies billions of dollars each year. Pharmaceutical companies are increasingly worried about counterfeiting and RFID tags on each product may help with this issue.
Advantages Of RFID Over Barcodes
Unlike barcodes, RFID technology does not require line of sight reading. The tag can be read through other items while barcodes require line of sight. This implies that a RFID reader could read a pallet of mixed products, all of which contain individual RFID tags, without having to physically move any of the items or open any cases. If the pallet was full of mixed items, the large number of RFID tags can be read almost instantaneously. The tags are not read simultaneously but the tags are read sequentially, but the time to read the tags would be microseconds.
The data on tag can be changed or added to as it passes through specific operations. Read-only tags are less expensive than read/write tags. RFID tags are less susceptible to poor environmental conditions where barcode labels can become unreadable. RFID tags can be sealed within a plastic enclosure eliminating many of the problems that affect barcodes in harsh environments where they are exposed to chemicals, heat and other harsh environments.