Towards an Experimental Characterization of the Effect of Ocean Surface Waves on Long-Range AUV Communication

Radio communications between an Autonomous Underwater Vehicle at sea and shore-based base-stations faces considerable challenges particularly if the antenna on the vehicle does not rise high enough above the water surface. At distances comparable to the maximum line-of-sight distance to a base-station at a given height, situations may occur where the local relative sea wave heights produce intermittent losses in communication between the radio on the vehicle and the basestation. These losses have an inherent periodicity due to sea surface wave motion. Here, we hypothesize that this periodicity could be exploited to make decisions about the timing of transmission, packet size and transmissibility of data as well as adaptation of the communication protocol to maximize data transmission. We propose using accelerometer information coupled with test sequences to learn the best strategy for communication optimization under these circumstances using Slocum gliders as a test platform. We present encouraging preliminary results based on data from a deployment currently underway in the Southern California Bight region and explore strategies to improve AUV-shore communications based on this data.