A wireless waterproof RFID reader for marine sediment localization and tracking

In this paper an innovative RFID reader to be employed in marine sediment localization and tracking is presented. This device has been realized within the "Smart Pebble" project, where an RFID based solution is employed to measure the displacement of a swarm of pebbles during predefined periods, in order to analyze the dynamics of a beach under the effect of stormy events, and then the impact of coastal erosion on the studied stretch of coast. The reader described in this paper has been developed to facilitate the localization of the so-called Smart Pebbles, i.e. real pebbles taken from the beach under study and provided with an embedded RFID transponder, then positioned on and under the seabed. The developed device is able to detect the presence of a Smart Pebble up to a 50cm distance, and its functioning has been tested at depths up to 5 meters for prolonged spans of time (up to 4 hours). Moreover, a wireless connection based on IEEE 802.15.4 has been set up between the reader and a laptop to allow the wireless transfer of the transponder ID from the reader to a laptop positioned on the beach.