active RFID (active radio frequency identification)
Active RFID (radio frequency identification) tags are continuously operating, battery-powered sensors that gather and transmit data to a reading device.
An active RFID system consists of a reader, tag and antenna. Unlike passive RFID tags that contains merely an antenna and a microchip with no internal power source, an active RFID tag has its own power source -- an on-board, long-lasting battery that enables the tag to transmit data continuously, regardless of whether it's in the field range of a reader.
There are two kinds of active RFID tags: transponders and beacons. A transponder only communicates when it's in the immediate vicinity of a reader. A beacon broadcasts constantly. A number of unique characteristics are specific to active RFID tags. Because the tags are often required to survive in harsh environmental conditions like extreme temperatures or precipitation, some are encased in a protective shell. Given the size requirements of the battery, wiring and the durable exterior, active RFID tags are larger than passive tags. Some also have on-board sensors that track environmental parameters like the temperature, humidity, fluid and power consumption. They can also be used for highly specific use cases, such as sensing when a container door is open and there is a change in temperature. This gives shippers an extra insight that allows them to make important adjustments, like rerouting a shipment if it spoils.
Active RFID tags require low signal strength to communicate and can broadcast up to and even beyond a range of 100 meters. The cost per tag ranges anywhere from $15 to more than $100, depending on its capabilities. The high cost generally makes active RFID tags too expensive for simple inventory applications. They are better for tracking high-value items like cargo. Industries that commonly use active RFID tags in addition to shipping and logistics include automobile sales manufacturing, health and medical, construction, mining, remote monitoring and IT asset management.
