Approach for long-range frequency domain chipless RFID tags towards THz

This paper presents an approach of an RFID system, which operates at frequencies of 100 GHz and above. Key issue of the system is an extremely small, chipless, tag, that is based on the ""dielectric resonant antenna"" (DRA) technology and provides identification as well as sensor capability. The tag uses radio-frequency backscattering techniques to encode and transmit the ID-data or measured values, respectively. The resonance frequency of a single DRA on the tag is determined as a peak in its radar cross section. To encode an ID number, the tag is built from several DRAs with slightly different resonant frequencies. A temperature dependency can be obtained by a temperature dependent permittivity of the DRA. The focus of the presented work is the estimation of the reading distance. Constraints are derived from previous work and typical indoor scenarios. The link budget calculation shows expected ranges of up to 20 meters.