Cato D H
Defence Science and Technology Organisation, Pyrmont, NSW, Australia.
J Acoust Soc Am. 1998 Sep;104(3 Pt 1):1667-78. doi: 10.1121/1.424379.
This paper describes three relatively simple methods of estimating source levels of marine animal sounds by estimating the source distance acoustically, using one or two hydrophones. The methods are logistically simpler than using arrays of hydrophones of known positions but are accurate over a smaller range of distances. One method makes use of the differences in the arrival times and levels of the signals received at two hydrophones from the same sound emission. No knowledge of the positions of the hydrophones is required, however, if these are known the position of the source can be determined, with left-right ambiguity. The second method uses the difference in received levels only, but requires the hydrophone spacing to be known. Adequate accuracy requires the source to be significantly closer to one hydrophone than to the other. Third, if the direct and surface reflected arrivals can be separated, the source level can be determined with a single hydrophone. The methods require accurately calibrated hydrophones.
本文介绍了三种相对简单的方法，通过使用一个或两个水听器以声学方式估计源距离，从而估算海洋动物声音的源级。这些方法在后勤方面比使用已知位置的水听器阵列更简单，但在较小的距离范围内更准确。一种方法利用了两个水听器接收到的来自同一声音发射的信号在到达时间和电平上的差异。不需要知道水听器的位置，但是，如果知道这些位置，则可以确定源的位置，但存在左右模糊性。第二种方法仅使用接收到的电平差异，但需要知道水听器间距。足够的精度要求源到一个水听器的距离明显比到另一个水听器的距离更近。第三，如果可以分离直达波和表面反射波，则可以用单个水听器确定源级。这些方法需要精确校准的水听器。
