What are passive tags?


This technology can in many ways be compared to a more advanced form of bar code.

Instead of a barcode, a tag is used. A tag is a small antenna (foil), which is fitted with a chip (the red dot):


Example of a passive tag



Such a tag would typically have a size of about 8 mm x 50 mm. while the small chip is 1.5 mm. in diameter.


When a tag enters a radio field, the antenna will generate energy to the small chip / processor and a value will be sent. Since the entry of a tag takes place via radio waves, it is not necessary that it is visible. This means that a given process can be carried out automatically – with no manual operation or difficulty finding the right barcode.


Advantages and Application

It is often the desire to optimize the business processes that are the direct cause of the companies choosing to invest in RFID. By optimizing business processes you can easier withstand competition from other companies when you become better at exploiting your resources. Here RFID has proven to be effective for collecting, managing and processing the information that always accompanies when products, materials, machinery and similar are exchanged between companies. The introduction of RFID can, for example, cause that companies:

  • Reduce shrinkage
  • Optimize inventory
  • Make (Flaskehalse??) visible
  • Ensure that it is the right product
  • Track misdeliveries
  • Handle returns
  • Automate processes


How passive RFID works

To read / write to a passive tag, you must use 4 components. An RFID reader has a built-in radio. For this radio, one or more antennas are connected. The connected antenna will generate a radio field. When a tag is approaching the antenna, the radio field will be intercepted by foil on the tag  (copper colored). This creates an electrical power and the on-chip (processor) will start working.

Now the tag begins to exchange data with the reader. The reader will then send the decoded value (SSCC code EAN128 or similar) back to a computer.



Setting up a portal


Example of a RFID Portal

Reading of passive tags is done in a defined area. Such an area will usually be around 5 meters wide and 4 meters high. The picture shows a practical embodiment of an RFID gate.

It’s what you call the registration of subjects that move around in predefined areas.

Other applications include conveyor belt, loading / unloading of goods (port / truck or x-docking), stock transactions, etc.


Performance and technology

It is possible to read several hundred tags as they pass through an area. 300 tags can be read per second. A passive tag is relatively cheap and easy to apply with applicators. A paper label can contain a “hidden” RFID tag. When the printer prints a label, it can simultaneously be tagged with RFID information. The organization that maintains and assigns company numbers for barcodes (GS1) is also responsible for the electronic version used in tags (EPC global).

Michael Winther


Tlf: +45 40 85 48 85

Michael Jensen


Tlf: +45 26 14 95 92

Lasse Cederquist

VP Sales

Tlf: +45 31 32 00 65

Service Desk

Tlf: 70 70 77 15