What are active RFID tags and how do they work?
The next logical step in the world of RFID tags bring advantages and characteristics of great value to the industry, which allow us to trace items in a manner that is far superior to the one provided by passive rfid tags.
An active RFID system consists of a reader, an active tag and an antenna. Unlike passive RFID tags that simply contain an antenna and a microchip without an internal power supply, an active RFID tag has its own power supply, which is usually an integrated long-life battery that allows the tag to transmit data continuously and uninterruptedly, regardless of whether or not it is in the field of action of a reader.
What frequencis are often used?
There are two main frequencies used by active systems: 433 MHz and 915 MHz.
User preferences, label selection or environmental considerations often determine the frequency to be used in each application.
Companies usually prefer RFID systems operating at 433 MHz for the simple reason that they have a longer wavelength, allowing them to work with materials normally considered difficult for RFID such as water or metals.
For more information on frequencies and RFID technology, you can visit our article: What is RFID.
TYPES OF RFID TAGS
There are two main types of active RFID tags: Transponders and Beacons.
- Transponders are very efficient active tags because they conserve battery life when the tag is out of reach of the reader. When a reader appears within range, it will send a signal and then the transponder will respond with a signal back with the relevant information.
- Transponders are typically used in access control systems, aircraft location, traceability, identification and navigation systems.
- Beacons, are active RFID tags that constantly emit information. In this case, the tag does not wait to hear the reader’s signal and instead sends the information contained in it every 3 – 5 seconds.
- The reading distance can reach hundreds of meters, but usually the transmitting power is adjusted to a lower power, thus preserving battery life while maintaining a considerable reading distance of about 100 meters.
- They are usually used in the oil and gas industry, as well as in cargo tracking and mining applications.
WHAT IS THE SHELF LIFE OF THE ACTIVE RFID TAGS AND INLAYS?
Active RFID tags are typically powered by a battery that lasts between 3 and 5 years, but when the battery fails, the active tag needs to be replaced.
The functionality of the system depends entirely on the type of tag chosen for the application. Most active RFID tags are responsible for withstanding adverse environmental conditions, such as extreme temperatures and humidity, which is why they are often encapsulated in a rugged housing that ensures a long lasting life.
As the market matures, the study of replaceable batteries begins to become a reality that will allow us to save on cost and duration. But until this technology is implemented, we will have to change our active tags every time they exhaust their battery.
HOW MUCH DOES AN ACTIVE RFID COST?
Nowadays, we can find a wide range of active tags, finding the cheapest around 15€ and being able to find the most expensive ones over 100€ depending on the product, therefore, given the investment required for an active RFID system, active tags are usually reserved for the tracking of high value assets or for items in which a precise tracking of the location is necessary for the success of the system, and due to the size of the battery, to a larger number of circuits, active RFID tags are, by necessity, much larger than passive tags.
Not only that, but some may have on-board sensors that track environmental parameters. These sensors can track humidity levels, temperature and other key identifiers for the system, causing the price per tag to skyrocket. For more information on RFID system pricing, go to RFID Costs.
– Extremely long reading range
– Increased labeling capabilities with associated technologies (GPS, sensors, etc.)
– Extremely rugged label options
– Much higher price than passive tags.
RFID tags are a fundamental component of any internal traceability system. They use radio frequency to transmit the information contained in them to a reader to identify an asset.
Radio frequency identification is a technology that allows us to identify almost any object wirelessly using data transmitted through radio waves. It knows the components that make up an RFID system.