1. How does an RFID system work?
The basics of an RFID system include the RFID tag and the interrogator or reader with an RFID antenna. Information is sent to and read from RFID tags by a reader using radio waves.
In passive systems, which are the most common, an RFID reader transmits an energy field that “wakes up” the tag and provides the power for the tag to communicate.
In active systems, a battery in the tag boosts the effective operating range of the tag and offers additional features over passive tags, such as temperature sensing. The chip then modulates the waves that the tag sends back to the reader and the reader converts the new waves into digital data.
Data collected from tags passes through familiar communication interfaces to business computer systems much in the same manner that data scanned from bar code labels is captured and passed to a business system.
2. What is the difference between active and passive tags?
Active RFID tags are also known as transponders because they have transmitters, which are always on, and their own power source.
Active tags use batteries for this power source, which runs the microchip”s circuitry and broadcasts a signal up to distances of 100 feet to an RFID reader.
Active tags are typically larger and more expensive than passive RFID tags, but can hold more data about the product and are commonly used for high-value asset tracking and for processes where tags can be re-used.
Active RFID tags may be read-write, meaning data they contain can be written over and changed.
Passive RFID tags are smaller and do not require their own power source.
Passive tags use the radio signal of an RFID reader to initiate the request for a reply.
Passive RFID tags have smaller read ranges, about 20 feet, and are in a read-only format.
Passive tags are less expensive making them ideal for compliance initiatives where the tag is disposed with product packaging.
At this point, passive tags and the respective hardware provide the most standardization and interoperability.
Semi-Passive tags are also available and offer users a boost in the typical 20-foot read range of a passive tag.
Semi-Passive tags use a small battery to power the circuitry of the chip, but communicate by drawing power from the RFID reader.
3. What are some initial benefits of RFID technology?
RFID technology can deliver benefits in many areas, from tracking work in process to speeding up throughput in a warehouse. The tangible benefits available through the deployment of RFID technology are:
Cost reductions through improved inventory and asset management
Increased revenues by reducing shrinkage and improving inventory turns
Theft prevention by identifying diversion points within the supply chain
Increased competitive advantage through improved productivity.
The truly real-time data available from the manufacturing floor with RFID allows companies to increase inventory control, improve production planning and tighten product distribution.
4. What are some of the most common applications for RFID?
Right now, the common buzz for RFID use is in compliance solutions for suppliers to retailers such as Wal-Mart and the DoD. RFID has numerous beneficial applications, hence the increasing number of mandates from major companies.
RFID can track everything from livestock on a farm to the wire crimper in a tool crib. Typically, RFID applications include asset tracking, access control and payment systems (toll road collection). Because of the enormous potential of RFID, it is beneficial to look at RFID beyond compliance initiatives.
Applying RFID to different areas of the supply chain will help product traceability, improve production planning and reduce costs for inventory management.
5. What are some of common characteristics of RFID?
RFID does not require line-of-sight to read and write the tag data.
RFID systems offer simultaneous identification capturing data from multiple tags within range of the antenna at the same time.
RFID tags read at very rapid rates – RFID can read tag identification codes at a rate of up to 1,000 tags per second.
RFID tags can be encapsulated in hardened plastic making them durable and ideal for harsh environments involving elements such as grease, dirt or paint.
Active RFID tags can support read/write operations, enabling real-time information updates as a tagged item moves through the supply chain.
