Applications for active and passive RFID tags

RFID technology is divided into three categories – Passive, Semi-Passive, and Active – depending on how the RFID label is powered and how the RFID label interacts with the device. To learn more, you can read the basic article about RFID.
Technical difference

Passive RFID tags have no internal energy source, but take energy from the radio waves sent from transmitters. These labels interact with the reader by responding to and modifying radio waves. Therefore, the reading range of the RFID tag is quite short (from a few centimeters to more than 4 meters), and memory is limited.
Active RFID tags, on the other hand, have a built-in power source (battery) and signal generator. Active RFID tags use these two components to transmit information to the reader. So, the range of active RFID labels can be up to tens of meters and has large memory.
Semi-passive RFID tags are a hybrid of the two above. They have a power source but do not have a signal generator, and use batteries to assist with connecting to the reader. Data from the reader is still being fed back, but with the help of the battery, it doesn’t need too much power from the reader – increasing range.

Application of each type of RFID label

Passive RFID tags

Because passive RFID labels have the lowest prices of the three, they are often used when handling large quantities of goods, requiring no long reading. In addition, passive RFID labels can operate at multiple frequencies, each serving a specific purpose.
Low Frequency (125kHz): Has a low reading range but can be read in environments with lots of liquids and humidity. This type of label is used to track pets as well as integrated in car locks.
High Frequency (13.56 MHz): Also has a low reading range (about 10cm) and the ability to operate in environments with lots of fluids and humidity. This is the most commonly used label, in access cards, library bookmarks, and laundry. NFC is also a technology that uses high-frequency RFID waves.
Ultra High Frequency (860-960 MHz): Has the longest reading range of passive labels (up to 4.5m) but does not work effectively in a liquid environment. This label is often used in cargo management, in the shipping sector.
Ultrasonic Frequency (2.45 GHz): The least common of passive labels, commonly used in cargo control and applications that do not require a long range, but require very fast data delivery rates. fast. This frequency is more commonly used with active RFID tags.

Active RFID label

Active RFID tags are the most expensive, but also have the longest range and are used on high-value assets. Since each label has a transmitter, the signal is transmitted very strongly and can be reflected in a metallic medium. Therefore, active RFID labels are very suitable for the requirements of long range and high metal warehouse environments.
Active RFID tags generally operate at two frequencies, and the main difference lies in the data transfer rate (the higher the frequency, the greater the transmission rate), memory, sensors, and shelf life.
Active labels typically operate at the 433 MHz frequency, within the ISO18000-7 standard. These labels are commonly used to track Pallets and Containers, as well as military assets. In the commercial sector, active RFID tags are used in the logistics industry, tracking large and high-value vehicles and assets.

The Microwave (2.45 GHz) Active RFID tag is used to collect road tolls, as well as the system to track the location of goods in warehouses, hospitals or office buildings.
There are several types of active labels that use different frequencies, but these are not very popular. Some labels use the UHF frequency (915 MHz) also for cargo tracking.
RFID tags are active with the use of batteries, so you can add sensors (temperature, humidity, or soil erosion), LEDs, buttons or do some other work. These special labels can be used to track temperatures in truck containers, in transporting frozen goods or for pharmaceuticals.

Semi-passive RFID labels

Semi-passive RFID labels generally use the UHF frequencies and the same protocol as passive RFID labels. However, they are further readable and can be attached to a sensor – usually a temperature sensor. These labels are used to track high-value goods, to track temperature-sensitive products such as pharmaceuticals, fresh food during transport.