DOA estimation techniques applied to RFID tags using receiving uniform linear array

Radio frequency identification (RFID) technology is one of the key technologies to make possible the Internet of Things (IoT). There are increasing needs to localize multiple RFID-tagged items which are closely spaced. As a result, localization techniques with higher accuracy yet low implementation complexity are required. This paper examines the applicability of the direction-of-arrival (DOA) estimation techniques using receiving uniform linear array for the localization of passive RFID tags. The theory is validated by experimental results using a dedicated measurement platform.