Sub-sea acoustic remote communications utilising an adaptive receiving beamformer for multipath suppression

Acoustic communications systems have found widespread use in both the offshore industry and marine sciences. For many applications such as remote operated vehicle (ROV) operation it is desirable to transmit video information in the form of camera pictures or side scan sonar images from the ROV to a surface vessel. For shallow water operation where the range is much greater than the water depth the most detrimental problem is that of inter symbol interference due to multipath. The paper presents a novel solution to this problem by using an adaptive beamformer to spatially filter the direct path signal from the multipath. Results obtained during sea trials are presented and demonstrate the effectiveness of the system.<<ETX>>