【作者】 张丽娜；

【导师】 刘利强；

【作者基本信息】 哈尔滨工程大学 ， 精密仪器及机械， 2012， 硕士

【摘要】 我国海洋面积辽阔，其中蕴藏着丰富的资源。开发和利用这些海洋资源、实时监测海洋动力环境和准确预报海洋灾难等方面，都对全方位、多手段、立体式实时监测海洋环境要素分布的变化规律提出了很高要求。随着海洋遥感技术的飞速发展，在海洋环境实时监测方面，X波段岸基雷达和航海雷达以其经济、稳定、实时、便捷且具有高时空分辨率等诸多的优点得到了广泛的应用。当X波段雷达电磁波入射到粗糙的海面时，后向散射产生的回波形成“海杂波”，同时由于流体动力调制、倾斜调制、阴影调制的作用使得X波段雷达的海杂波图像包含着丰富的海浪信息。本文介绍了基于X波段雷达“海杂波”图像序列的海浪信息提取方法和基本流程，分析了Yong等人提出的利用基本最小二乘算法反演海表面流信息的基本原理以及高阶次波和混叠效应对算法性能的影响，总结了现有的基于最小二乘原理的各种改进算法，针对各种算法的优缺点，提出本文基于PSO算法的海表面流反演方法。在利用PSO算法进行海表面流信息反演的算法设计中，重点讨论了主要参数的选取方案、位置信息初始化策略、适应度函数的构造方法以及算法流程设计等内容，充分考虑了各方面因素对算法性能的影响。提出通过模拟带有海表面流信息的海浪谱进行海表面流的反演实验，验证算法的精度；针对海表面流场时间稳定、空间均匀的特性，自定义了一种评价指标，用于验证和比较反演算法的性能。利用本课题组自主研发的海洋动力环境监测系统在福建省平潭县海坛岛进行了连续的海上数据采集，对实测的雷达“海杂波”图像序列应用最小二乘反演方法和本文提出的PSO反演方法进行了仿真对比实验。实验结果表明：PSO反演方法能够方便的引入对高阶次波和混叠效应的处理，受背景噪声影响小，与最小二乘反演算法相比，具有更高的反演精度和更好地稳定性和适应性。更多还原

【Abstract】 China’s vast ocean area, which is rich in resources. Development and use of these marineresources, real-time monitoring of ocean dynamic environment and accurate forecasting ofmarine disaster, etc., are all-round, multi tools, three-dimensional real-time monitoring ofchanges in the distribution elements of the marine environment law has placed enormousdemands. With the rapid development of marine remote sensing technology, real-timemonitoring in the marine environment, X-band marine radar, shore-based radar and itseconomy, stable, real-time, convenient and has a high spatial and temporal resolution, andmany other advantages have been widely used.This is the principle why X-band radar canmeasure sea-surface flow and wave information:When the electromagnetic waves of theX-band radar Incident to the Rough sea surface, they will make a Bragg resonant scatteringwith those wavelength of capillary wave approximately equals radar electromagneticwavelength caused by wind.The radar backscatter is receivered by radar receiver and then itforms sea clutter. While,longer-wavelength gravitational waves through the role ofhydrodynamic modulation, tilt modulation, shadow modulation to capillary waves appear inthe sea clutter echo images, it makes the X-band radar sea clutter image contains lots of waveinformation.This paper introduces based on the X-band radar "sea clutter" the image of the waves ofinformation extraction, and then briefly Yong and others made use of the basic principles ofleast-squares inversion method of sea-surface flow of information, and then summarizedbased on existing principle of least-improved algorithm to analyze the advantages anddisadvantages of various algorithms, which leads to the proposed PSO algorithm based on thesea surface flow inversion.In the use of PSO algorithm to simulation design information retrieval algorithms ofsea-surface information. We focused on the main parameters of the selected program,initialize location information strategy, the fitness function of the construction method andalgorithm design process, etc.,give full consideration to the various factors on algorithmperformance.This paper proposed the inversion experiments which use the waves spectrum withinformation of sea surface flow to simulation sea surface flow, used to verify the accuracy ofthe algorithm; Because sea-surface flow doesn’t substantially changed in a period of time andspace, so define an evaluation index to verify and compare the performance of inversion algorithms.Using the dynamic marine environment monitoring system which self-developed by ourgroup we get continuous marine data acquisition and data processing experiments at PingtanCounty, Fujian Province, the island of Hai Tan.Finally, in use of the Matlab program, theapplication of the inversion algorithm has been measured sea surface current radar "seaclutter" image, and then comparing the results calculated by the least squares.The resultsshowed that: PSO algorithm performance on the whole better than the least squares algorithm,and consider the image spectrum in the low-frequency effects, higher-order impact of waveenergy, and the aliasing effect of background noise, the use of PSO algorithm can still bemore satisfactory results. By comparing the experiments, we found that sea-surface flowduring the PSO algorithm inversion time inversion accuracy, stability, and adaptability.更多还原