A silver ink-jet printed UHF booster antenna on flexible substratum with magnetically coupled RFID die on-chip antenna

This paper presents an ultra low cost 868 MHz booster antenna, fabricated in an inkjet printing process on cheap flexible polyethylene terephthalate substratum. It significantly increases the operational distance of a highly miniaturized sensor UHF RFID grain (mm to m). This grain, equipped with an embedded temperature and voltage sensor, is manufactured in a low cost 130nm CMOS process. A coil on the chip is magnetically coupled to the booster antenna. In spite of displacing the sensor RFID grain up to 2 mm above the booster antenna, the functionality (similar to conventional RFID tag) is shown. Due to low cost processes and avoiding additional assembly works, the presented tag allows much reduced fabrication costs.