Why use side scan sonar? How does it work?
Side scan sonars are one of the most sought after and effective tools for underwater search. The reason; they can search large areas quickly and "see" what's on the bottom regardless of water clarity. A side scan finds things by sending out a sonar beam which sweeps over the bottom, reflects off any object laying on the bottom, and returns to the towfish. The sonar beam is tramsmitted and recived by transducers mounted on each side of the towfish. The received signal is sent through the tow cable to a topside processor box. After the sonar data is processed, it is sent to the laptop computer for display. The displayed image is a highly detailed two dimensional picture of the ocean, lake, or river bottom, and any objects lying there.
Side scans with low frequency transducers have excellent long range capability, but lower resolution. Side scans with high frequency transducers have high resolution, but shorter range capability. JW Fishers offers three side scan systems; the SSS-100K with a maximum scan range up to 600 meters per side for large search areas, the SSS-600K with a max scan range of 75 meters but high resolution to locate small, soft targets like drowning victims, and the dual frequency SSS-100K/600K which combines the best features of both high and low frequency in one system.
Tuesday, July 26, 2011
WWII GERMAN U-BOAT DISCOVERED
Posted by Voyage Adviser at 4:33:00 PM