RFID-based localization and tracking technologies

Radio frequency identification usually incorporates a tag into an object for the purpose of identification or localization using radio signals. It has gained much attention recently due to its advantages in terms of low cost and ease of deployment. This article presents an overview of RFID-based localization and tracking technologies, including tag-based (e.g., LANDMARC), reader-based (e.g., reverse RFID), transceiver-free, and hybrid approaches. These technologies mainly use the readily available resource of radio signal strength information or RSS change information to localize the target objects. A number of well-known approaches and their limitations are introduced. This article also indicates the challenges and possible solutions in the near and long terms. The challenges include multipath propagation, interference, and localizing multiple objects, among others. Most of these challenges exist not only for RFID-based localization, but also for other RF-based localization technologies.