Catflap shows the way to more sensitive RFID
A catflap that only lets cats wearing particular RFID tags into the house is being used as a technology demonstrator by a Cambridge start-up.
Nick Hill, CEO of Cambridge Resonant, the technology company behind the choosy flap, claims the RFID sensing technology it uses is ten times more efficient than in a standard reader, boosting battery life. He argues that the antennas in standard readers have limited efficiency, or Q factors, in order that they are not over-sensitive to things such as metal or water near the tag to be read.
“Our technology removes the upper limits to efficiency without drawbacks,” Hill said. He says the company’s patented non-linear resonant circuit technology can be attached to a high-Q antenna in such a way that the combination automatically tunes itself.
“Today one of the biggest issues in RFID tags is that a tag can’t get power to autotune, so it can’t autotune – it’s a Catch 22 situation,” said Hill. “Our technology allows autotuning in the tags without requiring external power. It pulls itself up by its own bootstraps.”
The ability to autotune a tag to a reader enables the reader to be much more selective when the tag is near metal, water or other tags – as is likely to be if each item in a case of consumer goods in a supermarket has been tagged.
“This has the potential to have a major impact on RFID, without breaking the laws of physics,” Hill said.
Hill and his colleagues hope to make a standalone business out of the RFID catflap, which is designed to stop stray cats following the house cat into the home. But they are also seeking an investment of £500,000 to develop the Cambridge Resonant technology for wider application.