CHAPTER 14
DIRECTION-OF-ARRIVAL (DOA) ESTIMATION OF IMPULSE RADIO UWB RFID TAGS
14.1 INTRODUCTION
Next-generation radio-frequency identification (RFID) technology demands a high-accuracy localization capability. Because impulse radio (IR) ultra-wideband (UWB) has the potential to provide centimeter-level location accuracy, the RFID industry has been developing a strong interest in IR-UWB. There exist two ways of locating the RFID tags: ranging- and directional-based localization. In the context of IR-UWB, while ranging-based approach enjoys high popularity, direction-of-arrival (DOA)-based approach receives less attention. This is due to the additional cost incurred for the use of antenna arrays and the increased complexity of the problem when a realistic dense multipath propagation is considered. The RFID industry has seen a growing interest in using impulse radio ultra-wideband (IR-UWB) as the wireless technology for the RFID [1–5]. Not only does the IR-UWB promise high-accuracy location estimation, but also the RFID tag based on IR-UWB requires lesser transmission power and can be built with simpler architecture [2]. These two traits make IR-UWB real-time location system (RTLS) different from sinusoidal-transmission-based RFID [6].
The indication of the promising ...
