基于四阵元基站的水下航行器自定位方法  

Self-Positioning Method for Underwater Vehicles Based on Subsea Four-Element Array

作　　者：翟京生 王晓健 钱治文 孙万忠 李杰 Zhai Jingsheng;Wang Xiaojian;Qian Zhiwen;Sun Wanzhong;Li Jie(School of Marine Science and Technology,Tianjin University,Tianjin 300072,China;Laboratory of Ocean Observation Technology,Ministry of Nature Resources,Tianjin 300072,China)

机构地区：[1]天津大学海洋科学与技术学院,天津300072 [2]自然资源部海洋观测技术重点实验室,天津300072

出　　处：《天津大学学报（自然科学与工程技术版）》2023年第3期252-259,共8页Journal of Tianjin University：Science and Technology

基　　金：国家重点基础研究发展计划(973计划)资助项目(2016YFC1401203);国家自然科学基金资助项目(42006168,11404079).

摘　　要：随着智慧海洋理念的普及和人工智能技术的发展,自主水下机器人、水下滑翔机等水下航行器在海洋科学调查、资源勘测和信息获取方面取得了重大进展,为了满足小型低成本水下航行器智能感知、自主作业的实际需求,同时降低其自主定位成本,设计并实现了一种基于海底四阵元基阵的自定位方法.首先,针对水声信道的复杂性,设计了具有时频特征明显、高峰值功率的声学频率梳信号作为传输信号,仿真实验证明该信号具有可靠的稳定性和抗噪性;其次,结合倒置的超短基线定位原理,设计了布放在已知参考点的四阵元基站,各阵元发出相互正交的声频梳信号,水下航行器在基阵声学作用范围内接收各个阵元混叠的声学频率梳信号,利用匹配滤波法对各信号单程飞行时间进行粗测;最后,针对声学频率梳的时域和频域特性,推导了接收信号与飞行时间的关系,利用相关分析法对各信号单程飞行时间进行精测,进而获取航行器与基站坐标轴阵元的测距和测向结果,结合倒置的超短基线定位方法,实现航行器的位置实时解算.水下实验结果表明,本方法复用率高、可操作性强,水下航行器只需携带单个接收信标即可完成定位计算,进一步降低了成本和系统复杂度.同时,也证明了声频梳信号的高可靠性,可在水下航行器端实现较高的自定位精度.With the advancement of smart ocean technologies and artificial intelligence,underwater vehicles(UVs),such as gliders,have made remarkable progress in marine scientific investigation,resource survey and information acquisition.To meet the needs for intelligent sensing of small and low-cost UVs and reduce positioning costs,this study implemented a self-positioning method based on a subsea four-element array.An acoustic frequency comb(AFC)with unique time-frequency characteristics and high peak power as the transmission signal was designed for the complexity of a hydroacoustic channel.The simulation results proved that AFC has reliable stability and noise immunity.Next,Combined with the principle of inverted ultra-short baseline positioning,an array placed at a reference point was developed,with elements emitting orthogonal AFCs.UVs received signals within the operating range of the array and utilized matched filtering to obtain an approximate measurement of the one-way flight time(OWFT)for each AFC.Finally,the relationship between the received signal and the OWFT for the time-frequency characteristics of each AFC was determined,correlation analysis was utilized to accurately measure the OWFT,then the range and direction measurements with each beacon element were obtained,and positioning was determined based on the principle of inverted ultrashort baseline.The results of underwater experiments showed that this method is reusable and operable,and UVs only need a single receiving beacon to complete localization,which reduces the cost and system complexity.Thus,this study shows the reliability of AFC,which can achieve high self-positioning accuracy on the UV side.

关 键 词：四阵元基站 水下航行器 倒置超短基线 自定位 声学频率梳 

分 类 号：TB56[交通运输工程—水声工程]