A Low-Cost Configurable ISO/IEC/IEEE 21451-7-Compatible Sensor Tag

Recent applications show a great potential of sensor tags in which a radio frequency identification (RFID) tag and one or more sensors are combined into a single unit. In this paper, a configurable low-cost sensor tag conforming to both ISO/IEC 18000-63:2013 protocol and ISO/IEC/IEEE 21451-7 sensor-tag interface standard is proposed. The sensor tag consists of a commercial tag front end and a newly developed baseband. The baseband is implemented using 0.13-μm CMOS technology and the functionality is verified on an field-programmable gate array platform. A combination of a finite state machine, microcontroller, and firmware is adopted in the baseband architecture in order to lower the cost and at the same time to attain high flexibility. The power consumption of the sensor tag baseband is 18 μW at 1.28-MHz clock frequency and 1.2 V power supply. The area of a sensor tag baseband increases ~20% comparing with a RFID tag without sensor supports.