CN111157998A - Dolphin underwater positioning system and method - Google Patents
Dolphin underwater positioning system and method Download PDFInfo
- Publication number
- CN111157998A CN111157998A CN202010002846.4A CN202010002846A CN111157998A CN 111157998 A CN111157998 A CN 111157998A CN 202010002846 A CN202010002846 A CN 202010002846A CN 111157998 A CN111157998 A CN 111157998A
- Authority
- CN
- China
- Prior art keywords
- hydrophone
- dolphin
- hydrophones
- central
- underwater positioning
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
- G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
- G01S15/06—Systems determining the position data of a target
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
- G01S15/88—Sonar systems specially adapted for specific applications
- G01S15/96—Sonar systems specially adapted for specific applications for locating fish
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
- G01S7/521—Constructional features
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- General Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
本发明涉及一种海豚水下定位系统及方法。该定位系统包括：多个水听器、可拆卸金属支架、重块、多通道采集卡和上位机；可拆卸金属支架包括多个金属固定板，所有金属固定板的第一端固定在一起形成可拆分金属支架；多个水听器分别固定于可拆卸金属支架的中心和每个金属固定板的第二端；可拆分金属支架的中心为金属固定板第一端固定的位置；可拆卸金属支架竖直悬浮于水下，可拆卸金属支架的底端悬挂重块；多个水听器用于接收海豚的回声信号；多通道采集卡和上位机位于船上，多通道采集卡用于采集每个水听器的信号；多通道采集卡的输出端与上位机连接，上位机用于根据多通道采集卡采集的数据确定海豚的位置。本发明可以提高海豚水下定位的准确度。
The invention relates to a dolphin underwater positioning system and method. The positioning system includes: a plurality of hydrophones, a detachable metal bracket, a weight, a multi-channel capture card and a host computer; the detachable metal bracket includes a plurality of metal fixing plates, and the first ends of all the metal fixing plates are fixed together to form Detachable metal bracket; a plurality of hydrophones are respectively fixed on the center of the detachable metal bracket and the second end of each metal fixing plate; the center of the detachable metal bracket is the position where the first end of the metal fixing plate is fixed; The metal bracket is disassembled and suspended vertically under water, and the bottom end of the detachable metal bracket is suspended with a weight; multiple hydrophones are used to receive the echo signals of the dolphins; the multi-channel capture card and the host computer are located on the boat, and the multi-channel capture card is used to capture The signal of each hydrophone; the output end of the multi-channel acquisition card is connected to the upper computer, and the upper computer is used to determine the position of the dolphin according to the data collected by the multi-channel acquisition card. The invention can improve the accuracy of underwater positioning of dolphins.
Description
Technical Field
The invention relates to the field of dolphin positioning, in particular to a dolphin underwater positioning system and method.
Background
The echo signal (click signal) of the dolphin is a high-frequency broadband narrow-pulse signal, and is used for echo positioning and target detection and identification so as to ensure the survival and activity of the dolphin in the sea. Although the click signals of different dolphins are different in characteristics such as pulse length, frequency, bandwidth and the like, the basic characteristics of the click signals belong to narrow pulse signals, and the click signals have higher resolution in the time domain.
In related documents in China, a single hydrophone is used for positioning the dolphin, the requirement on the measurement environment is high, and the unstable measurement environment can cause inaccurate positioning of the dolphin.
Disclosure of Invention
The invention aims to provide a dolphin underwater positioning system and method to improve accuracy of dolphin underwater positioning.
In order to achieve the purpose, the invention provides the following scheme:
a dolphin underwater positioning system, comprising: the device comprises a plurality of hydrophones, a detachable metal bracket, a weight block, a multi-channel acquisition card and an upper computer;
the detachable metal bracket comprises a plurality of metal fixing plates, and the first ends of all the metal fixing plates are fixed together to form the detachable metal bracket; the plurality of hydrophones are respectively fixed at the center of the detachable metal bracket and the second end of each metal fixing plate; the center of the detachable metal bracket is a position where the first ends of the plurality of metal fixing plates are fixed; the detachable metal support is vertically suspended under water, and the weight is suspended at the bottom end of the detachable metal support;
the hydrophones are used for receiving echo signals of the dolphin; the multi-channel acquisition card and the upper computer are positioned on a ship, and the multi-channel acquisition card is used for acquiring signals of each hydrophone; the output end of the multi-channel acquisition card is connected with the upper computer, and the upper computer is used for determining the position of the dolphin according to the data acquired by the multi-channel acquisition card.
Optionally, the two end hydrophones located on the same straight line are symmetrical with respect to the central hydrophone; the end hydrophones are the hydrophones positioned at the second end of the metal fixing plate, and the central hydrophone is the hydrophone positioned at the center of the detachable metal support.
Optionally, the hydrophone system further comprises a plurality of amplifiers, and the plurality of amplifiers correspond to the plurality of hydrophones one to one; the amplifier and the hydrophone are packaged into a whole, and signals of the hydrophone are amplified by the amplifier and then transmitted to the multi-channel acquisition card.
Optionally, the system further comprises a power supply battery pack, wherein the power supply battery pack is located on the ship, and a power supply cable of the power supply battery pack is connected with the power supply ends of the plurality of hydrophones and the power supply end of the multi-channel acquisition card.
Optionally, the multi-channel acquisition card is an NI-USB6356 type acquisition card.
Optionally, the number of the hydrophones is 5, the detachable metal bracket comprises four metal fixing plates, and first ends of the four metal fixing plates are fixed together; and the 5 hydrophones are respectively fixed at the fixed positions of the second end of the first metal fixing plate, the second end of the second metal fixing plate, the second end of the third metal fixing plate, the second end of the fourth metal fixing plate and the first ends of the four metal fixing plates.
Optionally, the upper computer is configured to determine the position of the dolphin according to a time difference between signals of each end hydrophone and the central hydrophone, which is acquired by the multi-channel acquisition card, and a distance between each end hydrophone and the central hydrophone; the end hydrophones are the hydrophones positioned at the second end of the metal fixing plate, and the central hydrophone is the hydrophone positioned at the center of the detachable metal support.
Optionally, the upper computer is further configured to generate a motion trajectory of the dolphin according to the position of the dolphin at different times.
The invention also provides a dolphin underwater positioning method, which is applied to the dolphin underwater positioning system and comprises the following steps:
acquiring the time when the secondary dolphin echo signal reaches the central hydrophone;
acquiring the time when the secondary dolphin echo signal reaches each end hydrophone;
calculating the time difference of each end hydrophone and the time difference of each central hydrophone for receiving the dolphin echo signal; the end hydrophone is positioned at the second end of the metal fixing plate, and the central hydrophone is positioned in the center of the detachable metal support;
obtaining the distance between each end hydrophone and the center hydrophone;
and determining the position of the dolphin corresponding to the current dolphin echo signal relative to the central hydrophone according to the time difference between each end hydrophone and the central hydrophone for receiving the dolphin echo signal, the distance between each end hydrophone and the central hydrophone and the underwater sound velocity.
Optionally, the determining the position of the dolphin relative to the central hydrophone according to the time difference between each end hydrophone and the central hydrophone for receiving the dolphin echo signal, the distance between each end hydrophone and the central hydrophone, and the underwater sound velocity further includes:
acquiring the position of the dolphin corresponding to the multi-time dolphin echo signal relative to the central hydrophone;
and fitting the positions of dolphins corresponding to the multiple dolphin echo signals relative to the central hydrophone to form the motion track of the dolphins according to the time sequence of the multiple dolphin echo signals.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects:
the invention can accurately quantify the distance between the sound production position of the dolphin and the receiving hydrophones, and further determine the sound production position of the dolphin, namely the position of the dolphin, through the parameters among the plurality of receiving hydrophones, thereby realizing the positioning of the dolphin in a certain range and having high positioning accuracy. By accurately quantifying the distance between the sound production position of the dolphin and the hydrophone, technical support is provided for accurately measuring the sound source level parameters of the sound signals produced by the dolphin. In addition, the dolphin movement track can be obtained within a certain time through subsequent data processing, so that the track tracking function is realized, and technical support is provided for research of dolphin behavior analysis.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.
FIG. 1 is a schematic view of the structure of the dolphin underwater positioning system of the present invention;
FIG. 2 is a schematic diagram of the arrangement positions of hydrophones in the dolphin underwater positioning system according to the present invention;
FIG. 3 is a schematic diagram of the coordinates of the hydrophone positions in the dolphin underwater positioning system of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
FIG. 1 is a schematic view of the structure of the dolphin underwater positioning system of the present invention. As shown in fig. 1, the dolphin underwater positioning system of the present invention comprises: the device comprises a plurality of hydrophones 1, a detachable metal support, a weight block, a multi-channel acquisition card 2 and an upper computer 3.
The detachable metal bracket comprises a plurality of metal fixing plates, and the first ends of all the metal fixing plates are fixed together to form the detachable metal bracket; the plurality of hydrophones are respectively fixed at the center of the detachable metal bracket and the second end of each metal fixing plate; the center of the detachable metal bracket is a position where the first ends of the metal fixing plates are fixed. The detachable metal support is vertically suspended under water, and the weight is suspended at the bottom end of the detachable metal support. For example, the metal fixing plates can be stainless steel fixing plates, a first end of each stainless steel fixing plate is provided with a fixing hole, a second end of each stainless steel fixing plate is provided with a fixing groove of the hydrophone, and when the device is used, the device is assembled on an experimental site and fixed by screws to form a support; after the experiment is completed, the bracket is disassembled into a plurality of fixing plates. The detachable metal support is easy to detach and install, and is firmer and more accurate in measurement result compared with a support of a PVC pipe in the prior art.
A plurality of hydrophones 1 are used for receiving echo signals of dolphin; the multi-channel acquisition card 2 and the upper computer 3 are positioned on a ship, and the multi-channel acquisition card 2 is used for acquiring signals of each hydrophone 1. Echo signals sent by dolphin belong to high-frequency broadband narrow-pulse signals, so that the acquisition card needs to have enough bandwidth and sampling rate, for example, an NI-USB6356 acquisition card can be used. The multi-channel acquisition card 2 is provided with a plurality of channels, and each channel corresponds to a signal of one hydrophone 1. The output end of the multi-channel acquisition card 2 is connected with the upper computer 3, and the upper computer 3 is used for determining the position of the dolphin according to the data acquired by the multi-channel acquisition card 2.
In a particular embodiment, the two end hydrophones located on the same line are symmetrical with respect to the central hydrophone. The end hydrophones are hydrophones positioned at the second end of the metal fixing plate, and the central hydrophone is a hydrophone positioned in the center of the detachable metal support.
In a specific embodiment, the dolphin underwater positioning system further comprises a plurality of amplifiers 4, and the plurality of amplifiers 4 correspond to the plurality of hydrophones 1 one to one. The amplifiers 4 and the hydrophones 1 can be packaged into a whole or fixed separately, one amplifier 4 and one hydrophone 1 form an array element, and signals of the hydrophone 1 are amplified by the amplifiers 4 and then transmitted to the multi-channel acquisition card 2. Every array element is fixed on the support, and the relative distance between the array element is stable when needing to guarantee to measure, and the array element interval should be 0.5m at least to subsequent data processing. As the hydrophones 1 and the amplifiers 4 are packaged into an array element, the spacing between the array elements is the spacing between the hydrophones 1, and the relative distance between the array elements is the relative distance between the hydrophones 1.
As another embodiment, the dolphin underwater positioning system further comprises a power supply battery pack 5, wherein the power supply battery pack 5 is located on a ship, and a power supply cable of the power supply battery pack 5 is connected with power supply ends of the plurality of hydrophones 1 and the multi-channel acquisition card 2. The power supply voltage of the power supply battery pack 5 can meet the requirement and can stably supply power for the hydrophone 1 and the multi-channel acquisition card 2 continuously.
As a specific embodiment, the arrangement position of the hydrophone in the dolphin underwater positioning system of the present invention is shown in fig. 2, and fig. 2 is a schematic view of the arrangement position of the hydrophone in the dolphin underwater positioning system of the present invention. In this embodiment, the number of the hydrophones 1 is 5, the detachable metal support comprises metal fixing plates 6-1, 6-2, 6-3 and 6-4, first ends of the four metal fixing plates are fixed at the same position, and the two opposite metal fixing plates are located on the same straight line to form a cross-shaped support. The 5 hydrophones are respectively fixed at the second ends of the metal fixing plates 6-1, the second ends of the metal fixing plates 6-2, the second ends of the metal fixing plates 6-3, the second ends of the metal fixing plates 6-4 and the fixed positions (namely the central positions) of the first ends of the four metal fixing plates. The whole detachable metal support is vertically suspended in water, and a weight 7 is hung at the bottom of the detachable metal support. The weight 7 is suspended in the water to reduce the vibration caused by the water flow, thereby improving the measurement accuracy of the whole device. Relative position between array element keeps stable, and every array element equals apart from the distance that can dismantle metal support center, and array element is apart from the distance that can dismantle metal support center to be 0.5m at least.
The upper computer 3 of the invention is provided with software for controlling the acquisition card to acquire data, and determines the position of the dolphin according to the signal time difference between each end hydrophone and the central hydrophone acquired by the multi-channel acquisition card 2 and the distance between each end hydrophone and the central hydrophone. And then further generating the motion track of the dolphin according to the position of the dolphin at different times. The process of determining the position of the dolphin will be described in detail, taking the example shown in fig. 2, which includes 5 hydrophones and a cross-shaped frame. The echo signals sent by the dolphin have a certain time delay when reaching different array elements of the receiving array, the data can be used for calculation by adopting a space model shown in figure 3, and figure 3 is a coordinate schematic diagram of the position of a hydrophone in the dolphin underwater positioning system.
As shown in fig. 3, the central array element of the cross is taken as the origin (0, 0, 0), the plane of the array element is XY, and the coordinates of the sound source point, i.e., the position of the dolphin, are S (x, y, z). In the figure, S is the sound source coordinate, AiIs the hydrophone number, RiLet v be the velocity of sound in water, t be the distance from the sound source to the different hydrophones0Time, Δ t, required for the dolphin sounding signal to travel to the central array elementiFor the time delay of each array element and the middle array element of the same signal, a is the array element interval, and the following equation set can be obtained according to the distance geometric relationship:
simply to obtain t0：
The distance r between the dolphin and the central array element is equal to vt0In addition, t is0Substituting the original equation system to obtain:
therefore, the coordinates of the dolphin position S in three directions can be obtained as the space coordinates of the sounding dolphin at the moment. By continuously calculating a plurality of data to form a group of signals, the motion track of the dolphin in the time period can be obtained.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.
Claims (10)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010002846.4A CN111157998A (en) | 2020-01-02 | 2020-01-02 | Dolphin underwater positioning system and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010002846.4A CN111157998A (en) | 2020-01-02 | 2020-01-02 | Dolphin underwater positioning system and method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111157998A true CN111157998A (en) | 2020-05-15 |
Family
ID=70561281
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010002846.4A Pending CN111157998A (en) | 2020-01-02 | 2020-01-02 | Dolphin underwater positioning system and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111157998A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113014875A (en) * | 2021-02-24 | 2021-06-22 | 自然资源部第三海洋研究所 | Dolphin sound image synchronous acquisition system |
| CN118276063A (en) * | 2024-03-26 | 2024-07-02 | 中国科学院声学研究所 | Quick-release and quick-assembly underwater sound measurement test device |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010151720A (en) * | 2008-12-26 | 2010-07-08 | Nec Corp | Transducer, line array antenna, and fan beam formation method |
| US20110228636A1 (en) * | 2008-09-17 | 2011-09-22 | Iranpour Kambiz | Cetacean Protection System |
| CN104143197A (en) * | 2014-07-31 | 2014-11-12 | 中国科学院自动化研究所 | A detection method for moving vehicles in aerial photography scenes |
| CN106569199A (en) * | 2016-07-29 | 2017-04-19 | 中国人民解放军海军工程大学 | Anti-frogman sonar transducer array |
| CN107505597A (en) * | 2017-08-03 | 2017-12-22 | 浙江大学 | A kind of ultra short baseline locating system and method based on depth information |
| CN107945206A (en) * | 2017-10-23 | 2018-04-20 | 夏仙强 | A kind of mobile object track determination methods of view-based access control model sensor |
| CN107942336A (en) * | 2017-11-13 | 2018-04-20 | 武汉大学 | Precision positioning method and system are marked suitable for the fish ultrasonic of Complex Water Environment |
-
2020
- 2020-01-02 CN CN202010002846.4A patent/CN111157998A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110228636A1 (en) * | 2008-09-17 | 2011-09-22 | Iranpour Kambiz | Cetacean Protection System |
| JP2010151720A (en) * | 2008-12-26 | 2010-07-08 | Nec Corp | Transducer, line array antenna, and fan beam formation method |
| CN104143197A (en) * | 2014-07-31 | 2014-11-12 | 中国科学院自动化研究所 | A detection method for moving vehicles in aerial photography scenes |
| CN106569199A (en) * | 2016-07-29 | 2017-04-19 | 中国人民解放军海军工程大学 | Anti-frogman sonar transducer array |
| CN107505597A (en) * | 2017-08-03 | 2017-12-22 | 浙江大学 | A kind of ultra short baseline locating system and method based on depth information |
| CN107945206A (en) * | 2017-10-23 | 2018-04-20 | 夏仙强 | A kind of mobile object track determination methods of view-based access control model sensor |
| CN107942336A (en) * | 2017-11-13 | 2018-04-20 | 武汉大学 | Precision positioning method and system are marked suitable for the fish ultrasonic of Complex Water Environment |
Non-Patent Citations (5)
| Title |
|---|
| 国家海洋局海洋科技情报研究所: "《海洋技术年鉴 1982》", 31 October 1983, 海洋出版社 * |
| 田蜜 等: "基于声学原理的卵砾石输移原型观测技术研究", 《水利量测技术论文选集 第10集》 * |
| 苑秉成 等: "《水中兵器试验与测试技术》", 30 September 2016, 国防工业出版社 * |
| 薛瑞超 等: "海豚定距定位测量方法研究", 《声学技术》 * |
| 郭世旭 等: "基于四元十字阵的低频换能器指向性检测方法", 《声学技术》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113014875A (en) * | 2021-02-24 | 2021-06-22 | 自然资源部第三海洋研究所 | Dolphin sound image synchronous acquisition system |
| CN118276063A (en) * | 2024-03-26 | 2024-07-02 | 中国科学院声学研究所 | Quick-release and quick-assembly underwater sound measurement test device |
| CN118276063B (en) * | 2024-03-26 | 2024-11-26 | 中国科学院声学研究所 | A quick-disassembly and quick-assembly hydroacoustic measurement test device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Walker | Physical and logistical considerations of using ultrasonic anemometers in aeolian sediment transport research | |
| Donelan et al. | Wave-follower field measurements of the wind-input spectral function. Part I: Measurements and calibrations | |
| WO2020228547A1 (en) | Sound velocity profile inversion method based on inverted multi-beam echometer | |
| CN102607388B (en) | Rotor displacement measurement device and method for planar motor | |
| JP6788272B2 (en) | Sound source detection method and its detection device | |
| CN101799560A (en) | Thunder and lightning locator with sound sensors and locating method thereof | |
| CN110248303A (en) | One kind being used for microphone array accurate calibration device and method | |
| CN111157998A (en) | Dolphin underwater positioning system and method | |
| CN113534161B (en) | Beam mirror image focusing method for remotely positioning underwater sound source | |
| CN109188362A (en) | A kind of microphone array auditory localization signal processing method | |
| CN106018550A (en) | Measurement device and method for acoustic characteristics | |
| CN109597021B (en) | Direction-of-arrival estimation method and device | |
| CN204594644U (en) | The contactless modal test system of a kind of acoustically-driven | |
| CN104062645B (en) | A kind of method measuring parametric array difference frequency ripple and same frequency small amplitude wave signal phase difference | |
| Kumar et al. | Wideband acoustic positioning with precision calibration and joint parameter estimation | |
| CN105606170B (en) | A kind of ultrasonic gas metering device and method with self study template | |
| CN111397721A (en) | Method and system for absolute calibration of co-vibrating vector hydrophone based on water surface boundary vibration measurement technology | |
| CN202230200U (en) | Ultrasonic Positioning and Trajectory Monitoring System for Cabled Submersible | |
| CN108415004A (en) | The measurement method of Scale Fiber-Optic Hydrophone Array full frequency band phase equalization | |
| CN103063868B (en) | Device and method for measuring flow rate of fluid | |
| CN111308421B (en) | Method for acquiring acoustic radiation of target free field in shallow sea | |
| Liu et al. | Research on DOA estimation method of single MEMS vector hydrophone based on pulse signal | |
| KR101703104B1 (en) | Method and system for measuring acoustic wave velocity and acoustic attenuation for sediment sample | |
| CN110440896B (en) | Ultrasonic measurement system and measurement method | |
| Huang et al. | Underwater sound speed profile construction: A review |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200515 |