RFID Indoor Localization Techniques

Abstract

Radio frequency identification (RFID) is a technique using two-way radio transmission pattern to transmit information through the device of interrogator (also called reader) and tag. It is considered to be one of the most popular techniques for internet of things (IOT). In this chapter, the authors study indoor localization techniques based on passive UHF RFID, which works around the frequency of 900MHz. Passive RFID has the advantage of reasonable reading distance, non-contact, easy deployment, and low cost. The tags do not need battery and it can harvest power through wireless charging. Due to those advantages, passive UHF RFID positioning has always been an active research area in the past few decades. This chapter discusses the key techniques in passive UHF RFID positioning, which include range-based, range-free, tag-based (device-based), tag-free (device-free), and improved positioning methods. All the techniques studied are suited to be implemented in RFID systems, each of which can be accommodated to a specific application scenario.