Radiofrequency identification (RFID) tags are teeny-little devices that use low-power radio waves for receiving, storing, and transmitting data to transmit readers. They are comprised of the components including a microchip, antenna, and a protective multiple-layer that holds all the components together.
The following are the basic types of RFID tags:
Passive– These types of tags aren’t equipped with an internal power source, instead, they are powered by the electromagnetic energy that’s transmitted from an RFID reader.
Active – They are equipped with their transmitter and power-source tag.
Semi–passive – They are comprised of a power source that’s incorporated into a passive-tag configuration.
The RFID tags can be used on a variety of surfaces and they are widely available in a wide range of sizes and designs. They come in a wide array of form factors including wet inlays, dry inlays, wristbands, stickers and, fobs, etc. Additionally, they usually operate in three frequency ranges, ultra-high frequency, high-frequency, and low-frequency.
Facts about UHF RFID tags
– Many of them don’t have a battery, and they are exclusively-powered by electromagnetic waves.
– Active and batter-assist tags with batteries can achieve much longer read ranges.
– There is no requirement of the line of sight, unlike barcodes.
– The way these tags talk or couple to the RFID reader is called backscatter.
– There is an algorithm on each tag that’s known as anti-collision which defines the order for replying if multiple tags are in the reading area.
– The read ranges vary from inches to 120 feet depending on the tag.
– Altogether, the integrated circuit has four memory banks including EPC, TID, USER, Reserved, etc.
– Each type of tag is designed with a uniquely-shaped antenna to ensure the best reactance.
The four memory banks are as follows
EPC memory bank – It’s well-equipped with the electronic product mode which can easily vary in length from 96 to 496 bits. Some manufacturers use a unique number, while others use repetitive numbers.
User memory bank – The user memory bank usually ranges from 32 bits to 64k bits and isn’t included in IC. If the tag is possessed with a user memory bank, it can be utilized for the user-defined data about the item. This could include information like type, date, serial, number, item, etc.
Reserved memory bank – This has an access to lock passwords, which enables the memory of tag to be locked up by the user and requires a password for viewing and editing.
TID memory bank – This type of bank has a tag identifier that is randomized by a unique number that is only set by the manufacturer and cannot be changed. To allow the reader to read this number rather than the EPC, the reading settings must be changed and accommodated.
Since there’s a chance that the tag’s EPC number is not unique, it’s indispensable to check before purchasing it from the UHF RFID tag manufacturer. If you purchase a tag without any unique EPC number, it has to be reencoded with a specific number.