Real time outdoor localization of buried RFID tags through statistical methods

The problem that we have addressed with the presented study is the absolute localization of buried RFID tags in an outdoor environment where the tag is. This is the scenario that we have envisaged when the RFID sensors are installed inside a moving body like a glacier or a slow landslide. During the tags dislocation it is possible to measure the depth of the installation and to define the absolute coordinate of the installation points using a topographic GNSS receiver. Afterwards the body evolves with time, moves and after a while (e. g. 1 month, 1 year) it is necessary to locate the sensors in order to quantify the absolute movement. To find the new location we have decided to investigate a multilateration-based localization technique. In this paper we describe the approach to develop a low cost system for the reading of the tags and for their localization without the need of expensive radar systems (e. g. GPR) to locate them.