5 Things Must Know for RFID Starters
On this post, we will cover RFID basics to help a newcomer gain a flavour of the technology. This is by no means comprehensive, and only aims to serve starters rather than the main dish itself.
RFID Types
RFID is commonly grouped into its operating frequencies.
- Low Frequencies or LF
RFID devices operate at 125 KHz - 148 KHz. The reading range at this frequency is typically 0.5 inches to 4 inches. - High Frequencies or HF
RFID devices operate at 13.56Mhz. The reading range of HF devices typically go from a few inches to several feet. With longer reading distances, HF enables other commonly installed applications such as RFID security gates, library management applications. Singapore National Library Board ( NLB ) uses HF technology for all its library branches. - Ultra High Frequencies or UHF
Commerical companies like Intermec and Alien Technology offer devices in this space. UHF devices operate in 915 MHz. UHF devices achieve the furthest reading range of the three. Typically from above 1 metre.
RFID Nemesis
There are several factors, arising from environmental or project requirement, that will degrade the smooth functioning of a RFID setup.
- Metal Effects
HF Devices suffers serious interface from metallic objects. Metallic objects blocks the path of HF signals, with the effect of degrading or in some circumstances cancel the readability of the devices. LF devices on the other hand works fairly well in both metal and fluid based environments. - Fluid Effects
UHF devices cannot negotiate RF signals in the presence of fluids such as the human body. The human body composed mostly fluid cause serious signal interference for UHF devices. To do a simple experiment. Place an UHF tag completely hidden in your palm, and bring the UHF tag completed enclosed in your palm close to a reader-antenna. The result is, the tag remains undetected even at close range.
Standards
International Standards defines a framework for interoperability between manufacturers of tags, readers and antenna. This creates a platform that allows different vendors to create hardware and software products to work with each other by adhering to operating standards. Again, the list is by no means comprehensive but aims only give you a flavour of the existing commonly applied standards in the RFID world.
EPCGlobal is a non-profit group that is leading the overall industry to develop standards for the use Electronic Product Code ( EPC ) in RFID. They are instrumental in driving the RFID Gen(eration) 2 specification and getting a slew of vendors to roll out products based on the new specifications. The RFID Gen 2 is submitted to the ISO standards committee.
ISO 15693 defines the ISO standard for devices operating in the 13.56 MHz frequency.
ISO 11784 & ISO 11785 defines the standards that regulate RFID usage for animals. While ISO 11784 defines the data structure of the identification code, ISO 11785 specifies the protocol aspects for the transponderd, data transmission requirements between the transponder and the transceiver.
RFID Gen 2 defines a specification that combines RFID technology, the Internet and Electronic Product Codes to provide a highly efficient information delivery throughout supply chains.
RFID Middleware
RFID Middleware is a software platform that manages RFID data. The middleware software layer filters RFID data from RFID Readers, and routes the data to a multitude of enterprise systems within the business. A significant component common with providers of RFID middleware software is the RFID device management. This layer of software negotiates events triggered by new RFID data detected at the RFID reader device level. New RFID data is subsequently filtered and translated to business related events and sent to the respective systems for appropriate response.
RFID Integration
RFID integration stems from the need for organizations to incoporate RFID technology into existing hardware and software infrastructure. Almost all the time, phase-in approach to RFID adoption is preferred in order to control the costs and risks of the investment. There is a certain amount of complexity involved in RFID integration. For sizeable projects, this will include the integration of the RFID middleware software that provides a platform for scalability.
For example, existing software process will have a built-in procedure to issuing unique identification codes for current inventory. By what means, can additional software be structured to seamlessly incoporate RFID to existing systems? Bearing in mind the freshly integrated RFID component should not disrupt the existing operations flow.
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