LUIS PEDRO
14164
RFID or Radio Frequency Identification systems are wireless, contactless data transmission systems based on radio-frequency electromagnetic fields, they are used mainly for id authentication and tracking purposes. An
RFID system is made of three basic components:
· The tag/transponder device
· The reader/interrogator device
· The computer and Software Infrastructure
For a successful implementation of an RFID system it is mandatory that the components above mentioned be present forming a RFID system. The tags are attached to items that we wish to track or monitor, and they emit messages that are decoded by the interrogator devices. The interrogator device upon identified the unique ID emitted by the tag on the database triggers a module on the software infrastructure and acts upon it accordingly. Some tags are embedded with writable memory, therefore instead of only transmitting information they are also able to record it.
TYPES OF TAGS
The RFID tags are classified into two main types based on their initiation source; those are the active tags and the passive tags. The active tags have an independent power source which is great because allows them to transmit a stronger signal allowing coupling devices to detect them even more precisely, however to have an independent power source also means that this devices are also larger in size and cost, the smallest devices are usually about the size of a deck of cards, they normally operate at high frequencies (455 MHz) and distance ranges that cover between 20 to 100 meters.
As for the Passive tags which are widely available and flexible given there accessible costs and relatively smaller sizes, that allow them to be integrated into common products and materials account for a great portion of the growth in RFID expansion. The data transfer sequence is normally activated when a tag comes within the range of the interrogator device and uses the electromagnetic signal captured through its antenna to power up its on-board capacitor (this process in known as inductive coupling), once the capacitor has built enough charge it enables the tag circuit to transmit a modulated signal reply to the reader.
The tag (passive) uses two main methods to modulate the ID signal to be transmitted to the reader; these methods are associated with the capacity of the on-board capacitor, and they are Low frequency (below 100 MHz) and backscatter (above 100 MHz). in which passive tags operate are 128 KHz, 13 MHz, 915 MHz or 2.45 GHz with ranges that go up to a maximum of 30 feet.
RFID STANDARDS
RFID development communities have raised several efforts to set standards and applications for RFID technologies, the standards defined specify protocols for the air interface, the application support and coding mechanisms. On the basis of this work the ISO (International Standard Organization) has established 3 RFID main standards:
· ISO 14443, for contactless systems
· ISO 15693, for vicinity systems
· ISO 18000, to specify the air interfaces for the variety of RFID applications
Apart from these standards there also widely accepted standards in the development community such as the EPC (Electronic Product Code) standard that covers the air interfaces, the format for the product information stored in the tag, the middleware and database used for storing data about the tags. The EPC standard is managed by EPCglobal, a non-profit organization turned towards standardizing the RFID technology application.
RFID APPLICATIONS ADVANTAGES
· RFID does not require line of sight to detect and read the tag
· RFID offers greater read range
· RFID readers can detect multiple tags simultaneously without having to scan each separately.
· RFID tags store more information than barcode tags, allowing history information on a product to be purposefully tracked.
CHALLENGES AND ISSUES IN RFID
The usage of RFID systems has also raised several concerns and challenges over the years, these concerns are evaluated from the technological and usage points of view. On the usage point of view a major concern is
privacy, since it disconcerting to have your information tracked without your knowledge, just in parallel this also raises a security concern where users do not know the information they are giving away and if they are willing to share that information.
RFID Application Best Cases
The most successful example of implementation of RFID technologies in supply chain management is provided by Wal-Mart that has an in house proprietary RFID system that proves the utmost efficiency and effectiveness of this technology in movement and product tracking, given all its warehouses and suppliers are due to apply the same technologies in order to maintain their business transactions. It is reported that Wal-Mart estimates its saves with the implementation of the system to be up to $ 8 billion a year. The US Navy has also offered an insight into the application of RFID systems with the successful completion of its pilot project to monitor the loading of supplies into cargo containers the Navy was successful in reducing the errors in records and improve its efficiency and speed in loading the containers, as well personnel could be assigned to other concerning areas effectively.
The FDA (Food and Drug Administration)is also conducting an investigation to determine the possibility of implementing RFID technology to ensure the safety in the supply chain and the authenticity of the prescription drugs, the idea is to have each shipment marked with an RFID tag which will then be read by the suppliers to ensure its authenticity. Furthermore Hospitals are known to have started applying RFID technology bracelets on newborns to ensure identity and track them in case they are removed from the facilities; this also helped reduce the margin for errors on surgical patients that had been tagged.
Schools are also implementing these systems to monitor attendance and track the children within the school premises.
References:
Welnsteln, R. RFID: A Technical Overview and Its Application to the Enterprise. Published by IEEE May, June 2005. www.cs.sunysb.edu/~jgao/CSE370-spring07/RFID.pdf
No comments:
Post a Comment