Most RFID technology is used to track assets and manage inventory, but not all RFID tags are created equal. Passive and active RFID tags are two types. Both can be used for tracking but they do it differently and are intended for different needs. This article will explain the difference between passive and active RFID tags, how they work, and which one may be the most suitable for your business or project.

Table of Contents

What Is a Passive RFID Tag?

There is no built in battery in a passive RFID tag. It, however, relies on the energy sent out by an RFID scanner to power and transmit data. These tags are lightweight, compact and cost effective since there is no internal power source.

Key Features of Passive RFID Tags

Energy is supplied from an RFID reader – No internal power source.
They have shorter signal range – Active RFID tags require a scanner closer to them.
They have no battery – Since they don’t have a battery, they can operate forever.
Affordable – Prices range from $0.08 per tag which makes them a cost effective option for large scale use.

What Is an Active RFID Tag?

Active RFID tags differ from passive tags in that they have their own built in battery and internal transmitter. This also means they have the ability to constantly send out signals without having to be powered up by an RFID reader.

Active RFID tags have some key features

RFID Reader Free – They don’t require an RFID reader to activate, they have their own power source.
Real time location tracking – They are constantly transmitting data and are thus perfect for real time location tracking.
The extended range – Readers can communicate with them from distances up to 150 meters.
Active RFID tags are more expensive than passive ones as they possess advanced functionality

How Active RFID Tags Work

Consider active RFID tags as GPS trackers. As they keep transmitting signals, these signals can be picked up from much farther away—sometimes as much as 150 meters, depending on frequency levels. For this reason, they are commonly used in real time tracking systems to help businesses monitor valuable assets as they move.

In order to set up an active RFID tracking system, you will need three basic parts: a reader, an active tag, and an antenna. Unlike passive tags, active tags transmit data in real time with their own internal battery, requiring no external power source.

How Passive RFID Tags Work

A passive RFID tag is like a keycard at an office building. It can be held up to the scanner and wakes up to transmit data to grant access. The tag is powered by the RFID reader’s signal just enough to send back its unique ID information.

Passive RFID tags are used by businesses with large inventories of physical assets because of their affordability and long life. Applications that don’t require long range tracking work best with them.

Active RFID vs. Passive RFID Main Differences

Tracking Capabilities

Active RFID tags are well suited for tracking expensive objects and assets that often move. Real time updates make them ideal for supply chain management, logistics, high value equipment tracking. In contrast, passive RFID tags are best suited for tracking items that don’t need constant monitoring, for example individual products in retail stores and or warehouse inventory.

Signal Range

Data can be transmitted over long distances, up to 150 meters, by active RFID tags. This is why they are ideal for tracking assets over wide areas such as hospitals, shipping yards and construction sites. Passive RFID tags have a short range and need to be closer to the reader than active tags in order to work; they are thus better suited to point of sale and access control systems.

Power Source and Longevity

Passive RFID tags do not have a battery and thus live forever as long as they are intact. This is especially suitable for applications where it is not possible to replace batteries, for example, tagging livestock. Active RFID tags have a built in power source, therefore, they have a limited lifespan based on battery life.

Cost Considerations

For people wanting to keep their costs down, passive RFID tags are the cheaper option. They are the go to choice as they are priced as low as $0.08 per tag for businesses that need to tag thousands or even millions of items. More expensive than passive RFID tags, active RFID tags are used for advanced tracking in high value asset management.

Applications of Active RFID Tags and Passive RFID Tags

There are different industries where both active and passive RFID tags can be used. Below are some real world examples of how they are used.

Where Passive RFID Tags Shine

Passive RFID tags are used to track inventory and prevent theft by stores. RFID tags are used when you see a security tag on clothing that beeps if you walk out without paying.
RFID tags in libraries: Embedded RFID tags into books so that they can be checked out quickly and without service, and so that the library can easily track its inventory.
RFID Enabled Wristbands or Tickets: They are used by concerts and sports stadiums to allow entry and allow crowd management.
Passive tags can be used by manufacturers to trace raw materials and finished products as they make their way through the production line.

Where Active RFID Tags Excel

Active RFID tags are used by shipping companies to track containers in real time as they move through supply chains.
Companies place active RFID tags on expensive equipment to identify it and prevent theft, and to track its usage.
Active RFID tags are used in healthcare to track the location of critical medical equipment, so as to make sure that defibrillators are always present when they are required.
Active RFID tags are used in vehicle tracking by rental car companies and fleet management services for security and monitoring vehicles.

How to Choose between Active and Passive RFID tags?

The choice of RFID tag depends on your own needs. Consider the following factors:

Active RFID is preferable in case of long distance tracking needs.
Passive RFID is less expensive in many applications.
The durableness of the Active RFID makes it preferred for harsh environments.
Intended Application: Assess the specific requirements of your use case. Passive RFID is used for example in waste management applications. A powerful passive RFID reader on a garbage truck can scan a lot of inexpensive passive RFID tags affixed to the waste bins. Passive tags have no maintenance concerns and this setup greatly reduces costs.

Conclusion

Active and passive RFID tags have their own roles in asset tracking, security, as well as logistics. Knowing their differences enables you to select the right solution for your needs. Passive RFID is the technology if you find yourself needing short range, low cost tracking. If long range real time monitoring is what you are after, active RFID is the better choice.