Liquid modulated antenna

摘要

One embodiment of a liquid-modulated antenna using an antenna of a type commonly used in the field of wireless identification which is placed within sufficient proximity of a source of liquid to allow the liquid to flow onto the antenna, thereby altering (modulating) the characteristics of the signal being transmitted from the antenna to a signal receiving unit.

主权项

1. A device for detecting a change in conditions comprising:
an RFID circuit, having an antenna, mounted to a substrate; a fluid-filled cell co-located on the substrate and separate from the antenna; and a passage for allowing the fluid inside the cell to flow from the cell onto the antenna to alter the response from the RFID circuit when the fluid flows out of the cell and onto the antenna.