In House Testing Capability for Towed Hydrophone Arrays

MSeis提供拖曳式水听器阵列，用于嘈杂的近海环境，以帮助减轻工业噪音对鲸类物种的有害影响，符合JNCC，IBAMA，BOEM等机构的指导方针;鲸鱼，海豚和鼠海豚。为了有效地做到这一点，我们要求水听器元件能够在整个频率范围内对海洋哺乳动物的发声做出响应，这通常被接受为1Hz-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进行控制扫描，测试新制造的阵列和从现场返回的阵列。这可以被视为一个相当主观的过程，因为从测试中没有获得任何数据，但是，我们确实将其视为改进测试方法的基础。通过我们的合作伙伴NPL，我们希望更准确地量化这种反应。该建议是通过放大器和专业扬声器提供更好的低频声音生成。为位于沿着10 m电缆的元件创建一种方法，该方法可以准确和重复放置，以保持完整性的一致性，并根据已知参考进行校准。这将涉及围绕我们的阵列配置设计的特定程序和索具的开发。索具将采用可测量XYZ龙门架的形式，将参考和测试水听器部署到水池中，能够执行更精确的对准，以改进水下测量。理解计算方法如何实现和理解结果。这将有望导致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;然后将其作为参考，以便我们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非常可靠的信息。此外，MSeis计划使用NPL的知识和指导来创建一个可变频率活塞式布置，以测试水听器元件在较低频率下的响应，理想情况下为0- 350赫兹，这是很难做到在一个相对较小的水池。在项目结束时，我们将能够测试所有4个水听器元件在一个阵列的完整性。这将使我们的客户有信心证明濒危物种的检测能力，如北方露脊鲸和侏儒鲸和矮抹香鲸。

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.