These sensors' main goal is to gather and transmits data to a device that performs reading data. The main difference between active and passive RFID’s that Passive RFIDs have no internal power source and are powered by electromagnetic energy that is obtained from the reader. On the contrary, an Active RFID use battery-powered tags.
The components of an Active RFID system are the reader, tag and antenna. The tags in an Active RFID are battery-powered and constantly broadcast their own signal. The two main frequencies that are used in these systems are 433 MHz and 2.45 GHz. The selection of the frequency depends on the user’s preference, the type of tag used and the environmental conditions. The two types of tags that can be used are transponders and beacons. The transponder tag is used when the reader sends a signal first and the transponder sends the signal back to the reader which the necessary information. These tags are efficient because of battery life. Beacon tags do the opposite and do not wait for the reader to send a signal. Instead, it will send out information constantly at set intervals.
The applications for Active RFIDs are that they are used to track real-time locations of objects that are in fast environments such as tolling. Active tags are used here as opposed to passive tags because they provide longer read proximity. Many companies also favour the 433 MHz. frequency because it provides a longer wavelength which allows companies to work in harsh environments such as metal and water. Transponder tags are commonly used in secure environments and payment systems.
