RFID tags consist of an integrated circuit (IC) attached to an antenna with typically a small coil of wires plus some protective packaging (like a plastic card) as determined by the application requirements. Tags are sometimes called 'transponders', and sometimes are called inlays, although technically an inlay is a tag mounted on a substrate that is ready to be converted into a smart label.
RFID tags can come in many forms and sizes. Some can be as small as a grain of rice. Data is stored in the IC and transmitted through the antenna to a reader. RFID tags are either no battery or self-powered by a battery. Tags also can be read-only (stored data can be read but not changed), read/write (stored data can be altered or rewritten), or a combination, in which some data is permanently stored while other memory is left accessible for later encoding and updates.
A tag power source can be passive, semi-passive or active, they are designed to function on specific frequencies or frequency ranges and come in many form factors such as labels, wristbands, buttons or embedded into items.
How Do Rfid Tags Work?
RFID Tags contain electronically-stored information that acts as a label for object identification. Tags identify, categorize and track specific assets. They contain more information and data capacity as compared to barcodes. Unlike barcodes, in an RFID system, many tags are read simultaneously and data is read from and written to a tag. You can categorize RFID tags in different ways by power source, frequency and form factor. In order to function, all tags need power to energize the chip and to transmit and receive data. The way the tag receives its power determines whether it is passive, semi-passive or active.
The majority of passive tags use EEPROM memory. Some are laser programmed at the silicon level. Many active tags utilize battery-backed SRAM. Passive tags (non-battery) typically have anywhere from 64 bits to 1 kilobyte of nonvolatile memory.
Active tags, such as those used in military tags, have memories as high as 128 kilobytes.
The typical operating temperature for an RFID inlay (tag) found in most smart labels is between -25º C and 70º C. Storage temperature typically is between -40º C and 85º C. These values will vary from manufacturer to manufacturer and will depend on the tag components. There are industrial tags available in the market that will withstand temperatures as high as 250º C, which could, for example, stand up to heat sterilization requirements for medical items.
What are the types of RFID Tags?
Tags that feature RFID inlays designed to provide optimal read ranges in most applications; Typically smaller in size, they are available in paper and synthetic materials for use on non-metallic surfaces, plastics or corrugate.
Tags that feature inlays that offer a higher level of read performance when placed on or near challenging materials or need to be read at an angle and where longer ranges are required. Typically larger in size, they are available in paper and synthetic materials for use on non-metallic surfaces, plastics or corrugate.
Labels with special designs featuring leading inlays that enable longer read ranges on-metal or for challenging applications.
Flag: Label design that flags away from an asset’s surface either distancing the inlay from it, or works with it, to provide reliable readability.
On-Metal: Label features a foam layer between inlay and adhesive to reduce the interference of metal to provide reliable readability.
Encapsulated Tags: Inlay inserted between two tag materials for applications where adhesive is not needed.
What are RFID Tags used for?
RFID Tags are used to identify and track any assets. They help to improve efficiency as they can scan a large number of tags simultaneously or those that could be inside a box or hidden from view.
RFID tagging provides visibility of product movement, streamlines distribution, improves demand forecasting, and makes manufacturing more responsive. Some of greatest advantages of RFID have been demonstrated in item-level deployments at apparel retail stores. Item-level tagging, where small non-descript RFID tags are typically embedded in existing apparel hang tags, are helping solve retailers’ challenges including out-of-stock levels, inventory accuracy, and helping customers quickly and easily find the size, style and color they are looking for.
Both General Purpose and Advanced tags can also be used in a variety of applications such as in Transportation and Logistics in distribution, shipping and receiving, warehouse operations including case, pallet and cross-docking applications. In Manufacturing, applications include work-in-process, product labeling, product ID/serial numbers, security and product lifecycle tagging. In Healthcare, they can be used for patient ID, specimen, laboratory and pharmacy labeling, document and patient records management.
Specialty labels are designed for use of more challenging applications. In Transportation and Logistics, they are used for fleet management and to track metal and liquid-filled containers. In Manufacturing, they can be used for asset tracking of tools, fixtures, metal parts, returnable containers and chemical drums. In Retail, for identification of jewelry, sunglasses and other small delicate items. IT asset tracking of mobile computers, printers, antennas and infrastructure components. Finally, in Healthcare, they can be used to track wheelchairs, beds, oxygen canisters, IV pumps and medical diagnostic tools.