Experimental Analysis of Radio Communication Capabilities of Multiple Autonomous Surface Vehicles

Autonomous exploration and rescue vehicles have been gaining wide interest over the past few years. Nowadays, demonstrations showed that those vehicles can fly, dive, surf, or drive while carrying out missions autonomously in some specific scenarios. Monitoring vehicles during missions is a crucial and challenging task to avoid the unnecessary cost of losing vehicles or potential accidents. In this paper, we present a cheap yet effective way for monitoring and communicating with autonomous vehicles over long distances by using off-the-shelf 900 MHz modems namely RFD 900+ and high gain antennas. Although the 900 MHz band has been around for over two decades, no complete analysis exists providing guidelines to use off the shelf modems for point-to-point and multi-point communications. Our main contribution is to provide experimental analysis of the communication capabilities in point-to-point and multi-point scenarios in both line of sight (LOS) and non line of sight (NLOS) using an affordable setup ($70 per modem). Experiments were carried out using autonomous surface vehicles (ASVs) as remote nodes and computers as Ground Control Stations (GCSs).