With passive RFID becoming more prominent in everyday use, understanding the differences between passive and active is essential for making the best decision for your facilities and their needs.
Passive vs. Active RFID - What Does It Mean?
RFID, or radio frequency identification, uses radio waves as a form of identification. Typically, this manifests as scanning for tags, and the tags are where the difference becomes clear. With passive tags, there are no batteries within the tag itself. They "draw power from the reader, which sends out electromagnetic waves that induce a current in the tag’s antenna."1 With active tags, there are batteries embedded into the tag as its own power source. "The power source is used to run the microchip’s circuitry and to broadcast a signal to a reader."1
5 Key Differences
1. Battery-Less Tags
As previously mentioned, passive RFID tags don't have their own power source, such as batteries. Because of this, passive RFID has the unique advantage of its tags never "dying" compared to active RFID tags and its need for the batteries to be replaced. If you don't replace them in time, you run the risk of dealing with ghost assets.
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What is a Ghost Asset? - Ghost assets are assets with active RFID tags on them, but the battery has died, causing both the asset and the tag to potentially be lost permanently. It becomes frustrating knowing that the asset is somewhere in the facility, tagged, with no way to find it. Passive RFID tags do not experience this issue.
2. Read Range
Because active tags have their own power source, they can broadcast a stronger signal, resulting in a much longer read range compared to passive tags. This can be beneficial in large-scale facilities or any area where tagged assets could be spread out over a wide space. Comparatively, passive tags have external factors affecting the read range, such as the strength of the scanner, what material the tag is attached to, if something is blocking the tag from the reader, etc.
3. Tag Size
Passive RFID tags are smaller compared to active RFID tags because they do not require batteries. They come in various shapes, sizes, and materials to suit different needs, as shown on the right. On the other hand, active tags are often bulkier, making it challenging to use and fit them on various assets.
4. Overall Cost
One of the main differences between passive and active RFID is the cost. The costs vary greatly depending on if you buy in bulk, the memory needed on the tag, the tag casing, the tag material, and more2. Passive RFID typically is the more affordable option between the two, with the average cost of a tag ranging from 7 cents to 20 cents, and active RFID tags start around $25 and increase quickly from there.
5. Infrastructure
What exactly is infrastructure? "Infrastructure includes the built environment and supporting elements: equipment, access, information technology (IT), systems and processes, sustainability initiatives and staff."3 Passive RFID requires significantly less infrastructure compared to active RFID. With active RFID, IT teams are heavily involved in installing, wiring, setting up, and activating the hardware. On the opposite end of the spectrum, passive RFID requires little to no infrastructure, making passive RFID a highly scalable solution that can be easily implemented in various facilities without the need for extensive technical support. It also makes a great option for facilities of all sizes since it's easy to start small and build as you grow or just hop right into a full-scale solution. From a tag specific perspective, passive tags are applied to their assigned asset and ready to go, compared to active tags that require staff to manually place the battery and have to consistently change it over the years of its use.
| Passive | Active |
| Fast Implementation | Lengthy implementation |
| Low Cost | High Cost / Maintenance |
| No Batteries Required | Battery / Battery Replacement |
| Minimal Infrastructure | High Count of Infrastructure, 3rd Party Infrastructure |
With all of this knowledge provided to you, you now understand the basics between passive and active RFID and will be able to make the best decision on the solution that's right for your facilities. If you want to know more about passive RFID, its capabilities, and how it can be beneficial for you, reach out to us at sales@pycube.com to learn more!
Resources
- https://www.dhs.gov/radio-frequency-identification-rfid-what-it
- 1https://www.rfidjournal.com/faq/whats-the-difference-between-passive-and-active-tags
- https://www.rfidjournal.com/faq/what-is-the-read-range-for-a-typical-rfid-tag
- 2https://www.rfidjournal.com/faq/how-much-does-an-rfid-tag-cost-today
- 3https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6465866/
