WO2020252945A1 - 基于泰勒展开的初始掠射角求解方法、声线弯曲修正方法和设备 - Google Patents
基于泰勒展开的初始掠射角求解方法、声线弯曲修正方法和设备 Download PDFInfo
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- WO2020252945A1 WO2020252945A1 PCT/CN2019/105178 CN2019105178W WO2020252945A1 WO 2020252945 A1 WO2020252945 A1 WO 2020252945A1 CN 2019105178 W CN2019105178 W CN 2019105178W WO 2020252945 A1 WO2020252945 A1 WO 2020252945A1
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- glancing angle
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- 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
- G01S15/66—Sonar tracking systems
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- 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
- G01S15/74—Systems using reradiation of acoustic waves, e.g. IFF, i.e. identification of friend or foe
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- 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
- G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
- G01S3/80—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using ultrasonic, sonic or infrasonic waves
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- 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
Definitions
- the invention belongs to the technical field of underwater acoustic detection and positioning, and specifically relates to an initial glancing angle solution method, a sound ray bending correction method and equipment for sound ray tracking.
- the acoustic signal propagates underwater it is subject to different salinity, temperature, depth and pressure, and its propagation speed is also different. Different sound speeds cause sound waves to no longer propagate in a straight line in the water. From the cross-sectional view, the sound ray between the emitter and the hydrophone is a curve instead of a straight line. Not only does the length of the sound ray become longer, the time it takes is also longer. .
- the commonly used method of ranging is the sound ray tracking algorithm, which simulates the sound ray path hierarchically according to the sound velocity profile to estimate the horizontal distance.
- Acoustic ray tracking requires an initial glancing angle. Use this angle as the starting direction to track the acoustic ray path. The precise initial glancing angle can also correct the direction finding error in the ultra-short baseline. Such scenarios often occur in practical applications.
- the measuring ship detects the underwater fixed transponder and obtains the signal round-trip delay of 2t. In the process of delay conversion position slant distance, accurate sound ray glancing angle is required.
- Voice tracking except for a small number of underwater acoustic sensors that can detect the direction of emission or incidence of the signal, most devices cannot accurately know the initial glancing angle of the sound ray. For this, the existing method uses a step search method in the range of 0-90° Find the most approximate initial glancing angle. This method requires sound ray tracking over the entire range, which is very cumbersome. If the step length is too large, the actual glancing angle may be skipped. If the step length is too small, the efficiency will be low and the calculation burden will increase. .
- the present invention proposes a method for solving the initial glancing angle based on Taylor expansion, a method for correcting sound ray bending, and computer equipment, which can quickly and accurately obtain the initial glancing angle and effectively solve the problem Under the influence of line bending, when the sound ray tracking method is used to correct the ranging error, the problem of the increase of the slope distance measurement error due to the inaccurate initial glancing angle.
- a method for solving the initial glancing angle based on Taylor expansion includes the following steps:
- the initial glancing angle ⁇ 0 is estimated by the triangulation principle , and the sine of the refraction angle ⁇ 0 complementary to the initial glancing angle ⁇ 0 Is the initial value of the iteration;
- a method for correcting sound ray bending obtains an initial glancing angle according to the initial glancing angle solution method described in the first aspect, and based on the initial glancing angle, the isocratic sound ray is tracked. The method obtains the horizontal distance, and then obtains the slope distance according to the Pythagorean theorem.
- a computer device comprising: one or more processors; a memory; and one or more programs, wherein the one or more programs are stored in the memory , And configured to be executed by the one or more processors, and when the program is executed by the processor, the method according to the first aspect of the present invention is implemented.
- the present invention solves the practical problem that the initial glancing angle cannot be accurately determined according to the measurement time delay due to the bending of the sound ray in underwater acoustic detection and positioning, thereby correcting the slant distance.
- the present invention reverses the initial glancing angle according to the sound ray tracking correction model developed by Taylor, and finally accurately corrects the sound ray error.
- the present invention does not need to search, the amount of calculation is small, and the estimated initial glancing angle has extremely high accuracy in most ranges, thereby correcting the sound ray bending and improving the measurement accuracy of the slant distance.
- the simulation experiment shows , In the 3000m depth, the ranging error does not exceed 10m.
- Fig. 1 is a flowchart of a sound ray correction method according to an embodiment of the present invention
- Fig. 2 is a schematic diagram of sound ray geometry according to an embodiment of the present invention.
- Figure 3 is a sound velocity profile according to an embodiment of the present invention.
- Fig. 4 shows sound ray traces at different angles according to an embodiment of the present invention
- Figure 5 is a comparison of initial glancing angle errors according to an embodiment of the present invention.
- Figure 6 is a comparison of horizontal distance errors according to an embodiment of the present invention.
- Fig. 7 is a comparison of slant distance errors according to an embodiment of the present invention.
- Fig. 8 is a schematic diagram of search and tracking when the glancing angle is 3.624° according to an embodiment of the present invention.
- Figure 1 is a flow chart of a sound ray correction method proposed by the present invention. Aiming at the problem of underwater acoustic ranging in a constant depth environment, the present invention proposes a method for solving the initial glancing angle based on Taylor expansion, using sound velocity profile and measurement The obtained depth and time delay information reversely deduces the initial glancing angle of the sound ray.
- the basic variables are shown in Figure 2:
- Output the initial glancing angle ⁇ 0 of the sound ray, the horizontal distance R and the slope distance r.
- Step 1 Select the initial iterative value of the initial glancing angle ⁇ 0 ;
- the initial grazing angle is calculated based on the slope distance estimated by the weighted average sound velocity as the initial value of the iteration.
- the weighted average sound velocity is obtained as follows:
- g i is the sound velocity gradient of each layer
- g i (c i+1 -c i )/(z i+1 -z i )
- the refraction angle is the angle between the sound ray and the vertical. Because the glancing angle and the refraction angle are complementary, the sine of the refraction angle follows snell's law, and p is a constant:
- ⁇ is used to represent the sine of the refraction angle
- the initial glancing angle ⁇ 0 arccos ⁇ 0
- ⁇ 0 is used as the initial value
- Step 2 Estimate the time delay with the isocratic sound ray tracking method
- the horizontal distance and time delay can be estimated from the initial glancing angle:
- ⁇ i c i /c 0 .
- Step 3 Calculate the initial value increment and correct it
- the initial value is updated based on the increment, and the initial value is corrected to:
- ⁇ 0 ⁇ 0 +d ⁇ 0
- Step 4 Complete the iterative process and solve
- Steps 2 and 3 are repeated continuously to iterate until ⁇ t ⁇ ( ⁇ is the threshold) or the number of iterations n exceeds the upper limit N to end the iteration.
- ⁇ 0 arccos ⁇ 0 is the final initial glancing angle, and the corresponding is obtained according to the isogradient tracking method
- the slope distance can be obtained according to the Pythagorean theorem.
- FIG. 3 A simulation test is carried out on a deep sea environment with a water depth of 3000m.
- the sound velocity profile is shown in Figure 3.
- Ten glancing angles ⁇ 0 at different angles are selected from 0 to 90° as the test.
- the corresponding horizontal distance R and time delay t are shown in Table 1. Shown.
- Figure 4 is a schematic diagram of sound ray trajectories at different angles.
- the present invention is combined with the empirical sound velocity method and the traditional search and tracking method. Compare. In addition to the time delay t, individual points are selected for the sound velocity in Figure 3 and white noise is added as the actual measured sound velocity profile. The average value of the white noise is zero and the standard deviation is 0.1m/s.
- the empirical sound velocity method uses the empirical sound velocity to convert the time delay into the slant distance.
- the weighted average sound velocity is used as the empirical sound velocity.
- the empirical sound velocity method does not consider the bending of sound rays, and the horizontal distance and glancing angle can be calculated from the triangle relationship.
- Both the search and tracking method and the present invention take into account the influence of sound ray curvature. It is necessary to calculate the initial glancing angle and then use the isogradient sound ray tracking method to track the sound ray to obtain the corresponding horizontal distance and slant distance. Therefore, the accuracy of the initial glancing angle and the calculation speed determine the accuracy and ease of use of the slope distance.
- Figure 5 is a comparison of the error of the initial glancing angle calculated by the present invention, the empirical speed of sound method and the search and tracking method. It can be seen that the error of the empirical speed of sound method is relatively large, and the present invention is at a large glancing angle (the transponder is near directly below) Compared with the search and tracking method, the present invention has a certain error. This is due to the fact that ⁇ 0 is near 0, which makes it necessary to face the problem of zero denominator or negative square root in the calculation process. A series of approximate processing increases the error, especially When the delay error is large, the situation becomes more serious. However, when the grazing angle is approximately less than 80°, the advantages of the present invention are highlighted.
- the calculation accuracy of the initial grazing angle is always higher than that of the search and tracking method, especially when the grazing angle is small, the error of the search and tracking method becomes larger. This is mainly because when the angle is small, the time delay is very sensitive to the small change of the glancing angle, and the relatively large search step size causes a large error.
- the size of the initial glancing angle error is reflected in the sound velocity tracking method to calculate the horizontal distance, and the slant distance error changes accordingly with the horizontal distance error, as shown in Figure 6 and Figure 7.
- the slant distance error of the present invention is relatively large in the opening angle of about 10° directly below the sound source, and has the smallest error in most other ranges.
- the horizontal distance error and the slant distance error increase with the increase of the initial grazing angle of the search under the small glancing angle, and it is even lower than the empirical sound velocity method.
- Table 2 The numerical results of this experiment are shown in Table 2.
- the search and tracking method requires a lot of attempts to search with a certain step length, and the accuracy is also affected by the compensation resolution.
- the glancing angle provided by the empirical sound velocity method can narrow the search range. When the initial glancing angle is large, the range is small, but when the initial glancing angle is large, the glancing angle and the actual glancing angle obtained by the empirical sound velocity method The gap is large, and the search workload is still huge, as shown in Figure 8.
- the present invention solves the practical problem of sound ray bending in underwater acoustic detection and positioning, and the initial glancing angle cannot be accurately determined according to the measurement time delay, thereby correcting the slant distance.
- the present invention reverses the initial glancing angle according to the sound ray tracking correction model developed by Taylor, and finally accurately corrects the sound ray error.
- the present invention does not need to search, the calculation amount is small, and the estimated initial glancing angle has extremely high accuracy in most ranges, thereby correcting the sound ray bending and improving the measurement accuracy of the slope distance.
- a computer device includes: one or more processors; a memory; and one or more programs, wherein the one One or more programs are stored in the memory and configured to be executed by the one or more processors, and when the programs are executed by the processor, each step in the method embodiment is implemented.
- the embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.
- a computer-usable storage media including but not limited to disk storage, CD-ROM, optical storage, etc.
- These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing equipment to work in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction device.
- the device implements the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.
- These computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operation steps are executed on the computer or other programmable equipment to produce computer-implemented processing, so as to execute on the computer or other programmable equipment.
- the instructions provide steps for implementing functions specified in a flow or multiple flows in the flowchart and/or a block or multiple blocks in the block diagram.
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- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- Acoustics & Sound (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
Description
θ0 | Θ 0 | R(m) | t(s) |
87.13° | 0.05 | 141.538 | 2.068144 |
80.21° | 0.17 | 486.888 | 2.092947 |
70.12° | 0.34 | 1014.897 | 2.181152 |
60° | 0.5 | 1603.690 | 2.343158 |
50.21° | 0.64 | 2271.849 | 2.592557 |
39.65° | 0.77 | 3175.169 | 3.009818 |
29.54° | 0.87 | 4333.020 | 3.631203 |
19.95° | 0.94 | 5855.171 | 4.531528 |
11.48° | 0.98 | 7650.351 | 5.655900 |
3.624° | 0.998 | 9674.782 | 6.961336 |
Claims (8)
- 根据权利要求1所述的基于泰勒展开的初始掠射角求解方法,其特征在于,所述迭代结束条件为时延偏差低于指定阈值或迭代次数达到指定次数。
- 一种声线弯曲修正方法,其特征在于,所述方法根据权利要求1-5中的任一项所述的初始掠射角求解方法得到初始掠射角,基于初始掠射角根据等梯度声线跟踪方法求得水平距离,再根据勾股定理得到斜距。
- 一种计算机设备,其特征在于,所述设备包括:一个或多个处理器;存储器;以及一个或多个程序,其中所述一个或多个程序被存储在所述存储器中,并且被配置为由所述一个或多个处理器执行,所述程序被处理器执行时实现如权利要求1-5中的任一项所述的方法。
- 一种计算机可读存储介质,用于存储计算机程序,所述计算机程序在被处理器执行时实现如权利要求1-5中的任一项所述的方法。
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