What is Passive Wireless Sensing Technology?
Imagine a wireless sensor without any batteries and transistors. For this device to function, a radio wave is generated from a ‘reader-unit’ and the reflected signals are analyzed. Analogous to an RFID-tag, a short-range indoor radar generates an electromagnetic pulse, here within the 2.4 GHz ISM band, the sensor absorbs the wave, stores it for a short time, modulates the wave with the measurand information and transmits it back to the reader. The reader, then analyses the received signal, retransmits the measured Temperature/Pressure/etc. via a standard protocol of your choice.
