An On-Body UHF RFID Tag With DDRR Antenna for Healthcare Data Streaming Applications

This paper describes the development of a Direct Driven Resonant Radiator (DDRR) antenna for an ultra-low power UHF RFID tag system, integrating accelerometer movement tracking using passive backscattering communications link. An outline system intended healthcare applications involving wireless detection, such as therapeutic recovery exercises is described. The comprises transponder connected to 4 cm (0.115λ) diameter, 1 mm thick (0.0028λ) skin-mounted antenna. Offbody read ranges 3.6 m with kB/s data communication are achieved. DDRR radiation pattern limiting factor in tracking, offering only limited angles which could be improved spatial diversity reader antennas.