In collaboration with Yadi Technology (Shanghai) and CSIC No.702 Institute, it takes 6

years for researchers at CAS Institute of Acoustics to work out a proprietary DTA-4000

acoustic deep drag system. Equipped with a high resolution deep scanning sonar, the new

system works with an innovative approach to process the signals on sea floors, or a

multiple sub-array automatic scanner, allowing a greatly enhanced performance and

reduced power consumption, with a maximum work depth approaching 4000m.

The new system was recently employed to examine optical cables as long as 640 km on the

sea floor for 145 hours, with the longest continuous operation for 116 hours. The

operation has produced reliable data on sea floor terrains and acoustic sections, though in

a rough sea condition.