Investigating sensor data retrieval schemes for multi-sensor passive RFID tags

Measuring multiple physical quantities are increasingly being demanded in commercial, biomedical and generally in ubiquitous applications. Although the recent emergence of passive sensor enabled RFID tags (sensor tags) provide new opportunities for these types of applications mainly due to the extended operational life and the small form factor, the energy harvesting nature of sensor tags hinders the use of multiple sensors in a single platform because of the requirement of additional energy to operate multiple sensors and subsequent reduction in the throughput. In this paper, we propose three, fast and energy efficient multi-sensor data retrieval approaches to obtain sensor data from sensor tags. We implemented a sensor tag with two sensors, an accelerometer and a barometer. Our extensive experiments on power consumption, operational range and throughput using the developed sensor tag revealed that, the proposed approaches can successfully be used for multi-sensor data retrieval and indicates that they can effectively be used in a range of real-world ubiquitous sensing applications such as fall prevention and food safety monitoring.