| 摘要 |
PCT No. PCT/US94/02833 Sec. 371 Date Jan. 22, 1996 Sec. 102(e) Date Jan. 22, 1996 PCT Filed Mar. 16, 1994 PCT Pub. No. WO95/00016 PCT Pub. Date Jan. 5, 1995An acoustic system and a method for repelling marine mammals from a region of water is disclosed. A plurality of acoustic transducers (10,12,14,16) are spatially dispersed beneath the surface of the water. The transducers (10,12,14,16) in sequence output high frequency acoustic signals into the water. The power of the acoustic signals starts at a low level and is gradually or incrementally increased to a high level which produces a signal beyond the threshold of pain of the mammals to be repelled. The mammals are therefore gradually repelled from the area without suffering permanent hearing loss. |
