Development of Wireless Passive Sensing Platform – Communication Issues

This paper presents a concept and investigations on wireless sensing platform utilizing Radio Frequency Identification (RFID) technology. The platform should serve as a completely passive wireless communication interface between any connected sensor (strain gauge, accelerometer, pressure sensor) and standard RFID reader. Entire energy needed for powering is delivered via magnetic coupling between the reader and a planar coil antenna, which is one of the platform parts. The same electromagnetic signal serves for communication and data acquisition based on backscattering technique. Designed platform could be used in many applications, especially in structural health monitoring (SHM) and for advanced diagnostic purposes. Scope of the parts of investigations presented in this work was acceleration of data rate between the platform and the reader. Efficient data transfer is the primary problem in many potential applications. By improvement of communication and data storage algorithms, as well as testing of different types of RFID readers, we achieve effective data rate on the level of 18 Kbit/s. By meaning of the effective data rate, it is defined data stored from sensor on EEPROM memory, not only UID, that is transferred in typical RFID systems.