In House Testing Capability for Towed Hydrophone Arrays

海生局根据JNCC、IBAMA、BOEM等机构的指导方针，提供拖曳水听器阵列，用于嘈杂的近海环境，以帮助减轻工业噪声对鲸类物种的有害影响；鲸鱼、海豚和江豚。为了有效地做到这一点，我们需要在整个频率范围内对海洋哺乳动物的发声做出反应的水听器元件，这通常被接受为1赫兹-150 kHz。为了证明这种频率响应，我们使用扬声器在整个频率范围内对新制造的和从现场返回的阵列进行了测试。这可以被视为一个相当主观的过程，因为没有从测试中获得数据，然而，我们确实将其视为改进测试方法的基础。对于我们的合作伙伴NPL，我们希望更准确地量化这种反应。这项提议是通过扩音器和专业扬声器提供更好的低频声音产生。为位于10米长电缆上的元件创建一种方法，这些元件可以准确和重复地放置，以确保完整性和校准与已知参照物的一致性。这将涉及围绕我们的阵列配置设计特定程序和装配。索具将采用可测量的XYZ龙门的形式，将参考和测试水听器部署到水池中，并能够执行更精确的对准，以改进水下测量。了解如何实施和理解结果的计算方法。这有望带来一些基本的计算机自动化。简单地说，我们将使用校准的水听器来确定它对各种声源的响应；这将作为参考，这样我们就可以通过与校准的水听器设备进行比较来获得阵列的校准读数。这反过来又提供了水听器的绝对灵敏度，这为我们的阵列性能提供了许多可靠的信息。此外，MSE计划利用NPL的知识和指令创建一种可变频率活塞振荡器类型的布置，以测试在较低频率(理想情况下为0-350赫兹)下的水听器元件响应，这在相对较小的池中是很难做到的。在项目结束时，我们将能够测试阵列中所有四个水听器元件的完整性。这将使我们的客户有信心证明对濒危物种，如北方露脊鲸和侏儒抹香鲸的检测能力。

MSeis provide towed hydrophone arrays for use in noisy offshore environments to help mitigate against the harmful effects of industrial noise on cetacean species in compliance with guidelines from bodies such as JNCC, IBAMA, BOEM etc; whales, dolphins and porpoise. In order to do this effectively we require hydrophone elements that will respond to marine mammal vocalisations across the full frequency range, this is generally accepted as 1Hz-150 kHz.To prove this frequency response we test both newly manufactured and arrays returning from the field in a pool using a speaker with a controlled sweep through the entire frequency range. This can be seen as quite a subjective process as no figures are obtained from the test, we do, however, see it as the basis for an improved testing method. With our partner NPL we would like to quantify this response more accurately. The proposal is to provide better low frequency sound generation through amplifiers and specialist speakers. To create a methodology for elements situated along 10m of cable that can placed accurately and repeatedly for consistency of integrity and calibration against a known reference. This will involve the development of specific procedures and rigging designed around our array configuration. The rigging will take the form of measurable XYZ gantry to deploy reference and test hydrophones into the pool with ability to perform more accurate alignment for improved underwater measurement. Computational methods to understand how to implement and understand the results. This will hopefully lead to some basic computerised automation.In simple terms we will use a calibrated hydrophone to determine it's response to our various sound sources; this will then act as a reference so that we can then gain calibration readings for the array by comparison to the calibrated hydrophone device. This in turns provides the absolute sensitivity of the hydrophone which provide much reliable information of our arrays performance.In addition MSeis plan to use knowledge and instruction from NPL to create a variable frequency pistonphone type arrangement to test hydrophone element response at lower frequencies ideally 0-350 Hz which is hard to do in a relatively small pool.At the end of the project we will be able to test the integrity of all 4 hydrophone elements in an array. This will give our clients the confidence to prove detection capability of endangered species such as Northern Right Whale and Pygmy and Dwarf Sperm whales.