Spanish firm Farsens has introduce the R-METER, a battery free RFID sensor tag capable of transmitting a unique identifier and the associated resistance measurement data to a commercial EPC C1G2 reader without the need of a battery on the sensor tag.
The device can measure resistances in a range from 100? to 500K? with an accuracy of ±3%. It also offers an extended operation range from 10? to 10M? with an accuracy of ±7%.
The R-METER has a 96 bits EPC number, a 32 bit TID and a password protected Kill command. The tag comes in a variety of antenna designs and sizes to adapt the performance to the required application in the 860-960 MHz band.
The reading distance for the battery-free thermistor tag is around 1.5 meters (5 feet) and it can be embedded in a wide variety of materials such as plastics or concrete. It can also be encapsulated in an IP67 or IP68 casing for usage in harsh environments. Evaluation kits are available.
The R-METER can be used without batteries at all, allowing for a wide range of opportunities monitoring resistance in applications where the accessibility is restricted, or where the use of batteries is not recommended. Since batteries are not needed, the sensor tags will never have to worry about autonomy.
R-METER tags offer R&D teams the opportunity of using proprietary resistance based sensors in battery-free mode. The R-METER provides battery-free and wireless communication means to those companies looking for this kind of solution. Typical resistance based sensors include thermistors, Light Dependent Resistors (LDRs), soil moisture sensors or strain gages amongst others.
Farsens designs and manufactures full passive RFID sensor solutions. Its proprietary UHF RFID IC allows Farsens to develop long range solutions for asset tracking – via the unique ID – and monitoring – via the attached sensor – without the need of any battery on the tag.