Antenna-less RFID tags work with metal and water


A RESEARCH team at the Centre for Nanoscale Science and Engineering (CNSE) at North Dakota State University have developed antenna-less RFID tags.

The antenna-less RFID tag would solve the problems associated with using radio frequency identification systems to track metal and liquid products.

A typical RFID tag is made up of an integrated circuit (IC) and an antenna. While there are different types of tags available, many don’t work well on metal objects or on containers filled with liquid.

Previous attempts to solve this problem have resulted in bulky tags that are easily destroyed by routine handling. The newly developed tags are inexpensive and easily manufacturable, while providing product tracking that meets EPCglobal Standards.

Many types of tags have to be spaced away from metal, since it changes the electromagnetic fields around the tags and destroys their ability to communicate. Many previous attempts at using RFID tags on metal objects solved the problem by placing an antenna on a spacer, this increased their thickness.

The tags developed by NDSU CNSE are less than 3mm thick and are placed directly on the metal, or could be recessed into the surface of a metal container. This is because the tags use the metal container as the antenna.