Chipless RFID tag with integrated sensor

A chipless tag based on multiresonators with integrated temperature sensor is presented. The tag consists of a UWB monopole antenna loaded with multiple cascaded spiral EBGs which have a 1:1 correspondence with data bits. The data bits are encoded into the spectrum hence the tag has a unique spectral signature. The chipless tag is less sensitive to tag orientation and has smaller size than earlier generations of the tag. The temperature sensor is a NTC thermistor which changes the radar cross-section of the tag antenna. The change in radar cross-section is used to determine the temperature while the spectral signature is used to identify the tag's unique ID. A proof-of-concept tag is developed and tested which has 6-bits and operates between 2-2.6 GHz. The chipless RFID tag is designed for ultra-low cost sensing applications.