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重物在落水和着底过程中都会产生瞬态声信号,这类信号可被运用于浅水区域水下目标定位。 针对浅水区域目标定位的问题,提出了一种基于小型立体五元基阵的瞬态声源快速被动定位算法。 在分析重物落水信号特征的基础上,选取合适的广义互相关加权函数求得传声器之间的声程差,运用快速最小二乘搜索算法进行声源定位。 结果表明:运用 5 传声器阵列可以同时兼顾定位精度和鲁棒性,且满足实时性要求,该方法可运用于浅水区域瞬态声源定位等领域。 相似文献
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赵冬艳 《数字海洋与水下攻防》2021,4(5):416-420
介绍了一种猎雷声呐脉冲信号被动定位的测向方法。反猎水雷采用被动声自导方式,利用猎雷声呐发射的窄带脉冲信号,采用自适应 notch 滤波器估计信号的包络、频率、相位差。采用时延差粗测与相位差精测相结合的方法实现时延估计。此方法不仅对 CW 脉冲信号可测向、测距,还可适用于调频、跳频信号。 该方法已通过仿真及实测数据验证有效。 相似文献
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深海空间站在母船伴随保障时面对恶劣天气存在安全风险及水下多平台作业低效的问题,传统的单一的保障船模式仅依靠超短基线等水下定位方法,水下平台定位速度慢、误差大、相互感知协作困难, 已无法满足要求。提出了一种基于通信信标的深海水声定位方法,采用宽带扩频通信进行时延估计,然后利用已建立的等效声速表查找等效声速,完成声线修正,从而提高了深海水声定位精度。并在实验室进行了深海水文条件下估计目标运动轨迹仿真,仿真结果表明该方法能够有效的提高水声定位精度。 相似文献
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本文论述了水下GPS系统的设计构思,系统的设计中使用了伪随机序列信号,介绍了基于时延差测量值和径向速度测量值的水下定位方法,文中给出了一组多普勒频偏估计的湖试结果,并给出了定位仿真结果。 相似文献
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本文介绍了一种多波束声呐回波信号时延的实时分析方法。通过实时提取信号的幅度及形状的综合特征计算同信号的时延。 相似文献
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现有对超短基线水声定位系统的误差研究多集中在静态领域，鲜有文献对其动态误差进行研究。 以 GAPS 作为主要试验设备对超短基线水声定位系统的动态误差进行了相关研究，提出了一种超短基线水声定位系统动态定位误差测试方法。使用圆概率误差半径进行度量，并通过湖上实验对 GAPS 的动态误差进行了测算，为水下定位系统校准/标定方法的研究奠定了重要基础。 相似文献
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《中国海洋大学学报(自然科学版)》2015,(10)
研究水声环境下匹配场定位中快拍数少和相干声源导致定位不准确问题。在水下目标定位的稀疏数学模型基础上,通过对测量矩阵中的列向量的模进行标准化,降低了由于距离原因对声源定位性能的影响;使用奇异值分解法对快拍数进行精简,降低了算法的时间复杂度;结合压缩感知理论的SOMP算法,实现高效的水下目标定位。仿真实例验证了该算法的有效性。 相似文献
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Positioning fisheries in a changing world 总被引：1，自引：1，他引：0
R. Quentin Grafton Ray Hilborn Lori Ridgeway Dale Squires Meryl Williams Serge Garcia Theodore Groves James Joseph Kieran Kelleher Tom Kompas Gary Libecap Carl Gustaf Lundin Mitsutaku Makino Thorolfur Matthiasson Richard McLoughlin Ana Parma Gustavo San Martin Ben Satia Carl-Christian Schmidt Maree Tait Lin Xiu Zhang 《Marine Policy》2008,32(4):630-634
Marine capture fisheries face major and complex challenges: habitat degradation, poor economic returns, social hardships from depleted stocks, illegal fishing, and climate change, among others. The key factors that prevent the transition to sustainable fisheries are information failures, transition costs, use and non-use conflicts and capacity constraints. Using the experiences of fisheries successes and failures it is argued only through better governance and institutional change that encompasses the public good of the oceans (biodiversity, ecosystem integrity, sustainability) and societal values (existence, aesthetic and amenity) will fisheries be made sustainable. 相似文献
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The IGS Real-time Pilot Project (IGS-RTPP) provides real-time precise orbits and clocks, which support real-time positioning for single stations over large areas using the Precise Point Positioning (PPP) technique. This paper investigates the impact of real-time orbits, network configuration, and analysis strategies on real-time PPP implementation and demonstrates the real-time PPP performance. One month of data from the IGS network is analyzed in a real-time simulation mode. Results reveal the following: (1) In clock estimation, differential approaches are much more efficient than the zero-differenced approach. (2) The precision of IGS Ultra rapid (IGU) orbits could meet the IGS-RTPP requirement for precise clock estimation and PPP positioning. (3) Considering efficiency and precision, a network with 50 stations is recommended for the IGS-RTPP. It is demonstrated that the real-time satellite clock precision is 0.1 ns supporting hourly static PPP with a mean precision of 2–3 cm in the North component and 3–4 cm in the other components. Kinematic PPP assessed with onboard GPS data collected from a buoy provided mean coordinate precision of 2.2, 4.2, 6.1 cm in the North, East and Up directions, compared to the RTK solutions. 相似文献
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Abstract Canada has increased the number of tsunami warning stations on the Pacific Coast from two to three. The last gauge was installed at the north end of Vancouver Island, thereby filling a large gap previously existing and providing full coverage along the coast. The record of gauges at two of the three locations is accessible either by telephone or by means of meteor burst communication, alleviating the difficulties experienced during the tsunami threat of May 6, 1986, when telephone communications were disrupted by heavy use. The gauge at Langara Island will be relocated in a more accessible and also a more tsunami‐responsive location at Rennell Sound in the Queen Charlotte Islands. All tsunami gauges also serve as tide gauges, recording the water level every 15 min. In the event of a tsunami, the recording interval can be altered to every 60 s. Suggestions have been made that Canada attempt deep‐sea recording of tsunamis off its Pacific Coast. Although this would be of great scientific value, no such program is contemplated at this time. 相似文献