Conventional sonar is normally based on anchors or ship-carriers, thus being subjected to such problems as a limited water range of vessels or a slow measurement of underwater objects. While the laser measuring instrument based on an airborne platform has better mobility, it can only be used in a crystal-clear water environment due to the impact of laser penetration in water.
The laser-acoustic remote sensing technology based on the energy and information transformation mechanism between laser and acoustic waves has long been considered a potential link in telecommunications and signal detecting between airborne platforms and underwater targets by the international academic community. It marks a significant direction for the future underwater sonar technology and marine remote sensing detection.
The research group, jointly headed by Prof. JIN Xiaofeng and Prof. XU Wen from the College of Information Science and Electronic Engineering, Zhejiang University, pioneered research on laser-acoustic remote sensing in China. It has made critical progress in recent experimental trials in the Jiangyin navigable section of the Yangtze River. The vessel-borne photo-acoustic prototype has managed to receive echo signals from the riverbed in a continuous and steady way. The echo signals, retrieved at a depth of 19 meters, are marked by a very promising SNR (signal-to-noise ratio).
This technology is anticipated to bring about major breakthroughs in such domains as quick underwater topographical measurement, underwater targets positioning, underwater rescue and air-water telecommunications in the future.
