CN101777954A - Underwater sound channel effective sound velocity estimating method based on intrinsic sound ray visual search - Google Patents

Abstract

Translated fromChinese

本发明是基于本征声线视在搜索的水声信道有效声速估计方法。对声源出射声线按不同掠射角跟踪，抵达接收点深度且满足能量约束条件时对其进行多途辨识并求取等效声速。在初始掠射角有效空间自适应变步长遍历完毕后，对各类多途抵达声线等效声速内插拟合。最后比较各空间采样点等效声速取最大值获得该点有效声速，实现空间区域各采样点本征声线的视在搜索，将各采样点有效声速存入矩阵，通过内插拟合迅速准确地获取任意两点的有效声速。本方法采取初始掠射角有效空间自适应变步长遍历、能量约束、多途辨识机制确保了复杂多途到达结构时有效声速也能准确获取，用本征声线视在搜索机制避免了声场的频繁计算，将准确度、适应度及速度较好地融合起来。

The invention is an estimation method of the effective sound velocity of the underwater acoustic channel based on the apparent search of the eigensound ray. The outgoing sound rays of the sound source are tracked at different grazing angles, and when they reach the depth of the receiving point and meet the energy constraints, multi-path identification is carried out and the equivalent sound velocity is calculated. After the traversal of the effective space adaptive variable step length of the initial grazing angle is completed, the equivalent sound velocity of various multi-path arrival sound rays is interpolated and fitted. Finally, compare the equivalent sound velocity of each spatial sampling point and take the maximum value to obtain the effective sound velocity of the point, realize the apparent search of the intrinsic sound rays of each sampling point in the spatial area, store the effective sound velocity of each sampling point into the matrix, and quickly and accurately fit through interpolation The effective speed of sound at any two points can be obtained accurately. This method adopts the adaptive variable step length traversal of the initial grazing angle effective space, energy constraints, and multi-path identification mechanism to ensure that the effective sound velocity can be accurately obtained when complex multi-path arrival structures are used, and the apparent search mechanism of intrinsic sound rays avoids the sound field The frequent calculation of the algorithm integrates accuracy, fitness and speed well.

Description

Underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent

Technical field

The invention belongs to underwater sound propagation and acoustic positioning technique field, be specifically related to the effective sound velocity method of estimation that sound wave is propagated at any point-to-point transmission in the underwater acoustic channel.

Background technology

In aqueous medium,, be marine acoustics quantitative study the earliest about the research of the velocity of sound.1827, Colladon and Sturm measured the propagation velocity of sound wave in water at Geneva Lake, and the result of gained is near modern estimated value.Under the promotion of subaqueous sound ranging and echo depth sounding technology, a period of time has the people comparatively accurately to measure the acoustic velocity value in the ocean subsequently.Studies show that the velocity of sound has vertical demixing character in the ocean, often provide the variation of the velocity of sound in the practical engineering application, perhaps the functional relation of the velocity of sound and the degree of depth with the degree of depth.Obtain yet be applied in the Yu Haiyang channel arbitrarily the velocity of sound of point-to-point transmission more widely, because all be the accurate acoustic velocity values of needs when the acoustic propagation time is converted to propagation distance in the ocean.Estimate that by test the velocity of sound of any point-to-point transmission is inconvenient and is difficult to finish at short notice, and the time variation of marine environment makes measured value accuracy after measurement is finished reduce greatly.

Chinese scholars is obtained with regard to the velocity of sound of underwater acoustic channel and has been launched research.Vincent is when the hydrolocation of research deep-sea, the velocity of sound with any point-to-point transmission in the ocean space is defined as effective sound velocity ([1] Vincent first, H.T.and Hu, S.L.J., " Method and system for determining underwater effectivesound velocity; " United States patent application, Patent No:US 6388948B1) and proposed the acquiring method of effective sound velocity, but the method is only applicable to the finding the solution of effective sound velocity of direct wave region.Sun Wanqing ([2] shallow sea acoustic positioning technique and application study. the doctorate paper .2007:88-91 of Chinese Marine University page or leaf) a kind of effective sound velocity method of estimation based on finite state automata proposed, though the method has been considered sub-bottom reflection, but consider fully inadequately to sea surface reflection, amount of calculation is very big during with little step length searching.Under some special hydrology condition, reflected sound is first then than direct sound wave, and two kinds of algorithms all can accurately not provide effective sound velocity.Lin Wangsheng (research of [3] underwater acoustic channel emulation and sound ray correction technique. the master thesis .2009.:28-31 of Harbin Engineering University page or leaf) a kind of effective sound velocity acquiring method that calculates based on sound field proposed, though this method can accurately provide any 2 effective sound velocities, yet need carry out the each point sound field, amount of calculation is very big.

Summary of the invention

The object of the present invention is to provide a kind of deep-sea channel that both had been applicable to, be applicable to shallow sea channel again, and can quick and precisely estimate the effective sound velocity method of estimation that sound wave is propagated at any point-to-point transmission in the complicated hydrology lower channel.

The object of the present invention is achieved like this:

(1.1) initialization basic parameter mainly comprises sea, submarine frontier characteristic initialization, and the vertical velocity of sound distributed-hierarchical quantification in ocean, acceptance point spatial sampling scope and sample rate, the initial glancing angle useful space are provided with;

(1.2) sound source outgoing sound ray is followed the tracks of by different glancing angles, when sound ray arrives at the acceptance point degree of depth it is carried out the judgement of energy constraint condition, carries out many way identifications and ask for the equivalent velocity of sound when sound ray satisfies the energy constraint condition;

(1.3) after initial glancing angle useful space self adaptation variable step traversal finishes, the match of sound ray equivalence velocity of sound interpolation is arrived on all kinds of many ways;

(1.4) all kinds of equivalent velocities of sound that arrive at sound ray of comparison level sample point obtain each effective sound velocity;

(1.5) be that parameter deposits each sampled point effective sound velocity in matrix with the sound source degree of depth, the acceptance point degree of depth and the two horizontal range, the change sound source degree of depth, the acceptance point degree of depth are set up two dimension or three-dimensional effective sound velocity matrix according to the step of front;

(1.6), look into and get the match of effective sound velocity matrix interpolation and obtain effective sound velocity any in the underwater acoustic channel at 2 according to propagation distance or time.

The present invention can also comprise some features like this:

1, described sound source outgoing sound ray is followed the tracks of by different glancing angles, is to take initial glancing angle useful space self adaptation variable step traversal mechanism, adjusts the step-length that glancing angle changes when promptly utilizing the fructufy of at every turn following the tracks of.

2, described energy constraint condition mainly comprises seabed, sea filter criteria, and is provided with apart from the border.

3, described many way identifications be to the initial glancing angle of sound ray, sea sub-bottom reflection number of times, the number of times that reverses is added up up and down, judges its type.

4, described looking into got the match of effective sound velocity matrix interpolation and obtained effective sound velocity any in the underwater acoustic channel at 2 and be: according to propagation distance or time, the effective sound velocity matrix is carried out nearest two sampled points of sound field judge index, to this 2 effective sound velocity interpolations match.

Core technology content of the present invention is intrinsic sound ray apparent searching idea.Basic assumption according to many ways channel model, acoustical signal is sent the back from sound source and is arrived the space point along different paths, the signal that this point receives is all intrinsic sound ray sums, and all there is an equivalent velocity of sound in every sound ray, promptly receives and dispatches the ratio in both air line distances and this sound ray propagation time.Effective sound velocity is for arriving at the equivalent velocity of sound of sound ray correspondence the earliest.

Intrinsic sound ray apparent searching idea adopts the basic assumption of many ways channel model, but be not conceived to the search of intrinsic sound ray, in the sound ray tracing process, extract each sampled point equivalence velocity of sound useful information, the intrinsic sound ray that is equivalent to each sampled point is placed on record, and relatively each is levied sound ray equivalence velocity of sound size at all and obtains effective sound velocity at last.If the method that adopts document [3] to provide, the effective sound velocity that obtain M sampled point will be carried out M sound field and be calculated, just and glancing angle space traversal of employing apparent searching algorithm can obtain the effective sound velocity of M sampled point, efficient has improved M times.

The initial glancing angle useful space self adaptation variable step traversal mechanism main contents that the present invention includes are: the initial glancing angle useful space is a sub spaces of [90 °, 90 °], i.e. not only upwards outgoing but also outgoing downwards of sound ray.This mechanism gives all kinds of equal chances of sound ray that arrive at, and regional sound ray leaks choosing or mistake is selected can not cause sound field to be suddenlyd change.The method that adopts document [1] to provide in the direct sound wave shadow zone can not provide effective sound velocity.The sea reflected sound arrives at prior to direct sound wave under the complicated hydrology, and the method that adopts document [2] to provide is wrong choosing to occur.Initial glancing angle self adaptation variable step refers to that the result who follows the tracks of according to each sound ray is adaptive to the step-length adjustment.This mechanism has been accelerated the speed of initial glancing angle useful space traversal under the situation that does not influence computational accuracy, improved computational efficiency.

The sound ray energy constraint that the present invention includes mechanism main contents are: carry out seabed, sea filter criteria and judge and arrive at apart from the border and judge.This mechanism has guaranteed that all kinds of sound rays that arrive at each point all place on record, arrives the situations of structure for the many ways of complexity, can not cause leaking choosing or wrong choosing, and can reject all kinds of extremely weak sound rays that arrive in the sound ray.

The many ways of the sound ray that the present invention includes identifications mechanism main contents are: to the initial glancing angle of sound ray, sea sub-bottom reflection number of times, the number of times that reverses is added up up and down, judges its type.All kinds of to arrive at sound ray varying level distance effective sound velocity be gradual change, can arrive at the match of sound ray equivalence velocity of sound interpolation and obtain each spatial sampling and put the equivalent velocity of sound similar, so the many ways of sound ray identifiers is made as and realizes that the apparent search provides the foundation.

Any 2 the effective sound velocity interpolation match that the present invention includes is obtained main contents and is: according to propagation distance (or time), the effective sound velocity matrix is carried out nearest two sampled points of sound field judge index, to this 2 effective sound velocity interpolations match.

Description of drawings

The basic model that Fig. 1 asks for for several effective sound velocities;

A figure is the basic model that document [1] effective sound velocity is asked for;

B figure is the basic model that document [2] effective sound velocity is asked for;

C figure is the basic model that the present invention adopts.

The flow chart that Fig. 2 estimates for effective sound velocity;

Fig. 3 is the hydrology of certain marine site actual measurement;

Fig. 4 is the track (sound source is positioned at 5m, receives to be positioned at 30m) of a secondary tracking sound ray;

Fig. 5 is all kinds of sound ray equivalence velocities of sound (sound source is positioned at 5m, receives to be positioned at 30m) that arrive at of one dimension effective sound velocity matrix correspondence;

Fig. 6 is one dimension effective sound velocity matrix (sound source is positioned at 5m, receives 30m);

Fig. 7 is two-dimentional effective sound velocity matrix (sound source is positioned at 5m, receive and to lay respectively at 20,30,40m).

Embodiment

For example the present invention is done description in more detail below in conjunction with accompanying drawing:

Under certain marine environment, the flow chart of estimating effective sound velocity as shown in Figure 2, key step is:

1. initialization basic parameter process mainly comprises the initialization of ocean environment parameter:

(a) depth ofwater 90m, 2 grades of sea situations, the seabed is smooth, seabed substrate density 2.036kg/m³, Bottom sound speed 1836m/s; The reflection coefficient of sea surface is-0.9;

(b) velocity of sound vertical distribution is divided into several layers with it as shown in Figure 3;

(c) receiving hydrophone spatial sampling scope is 100-5000m, and the level sampling interval is 10m;

(d) setting the initial glancing angle traversal useful space is [60 °, 60 °].

(f) sound source is positioned at the 5m depths, receives to be positioned at the 30m depths.

2. sound ray is outwards advanced with certain initial glancing angle, it is followed the tracks of, when it arrives at the acceptance point place degree of depth, it is carried out the energy constraint condition judgment, promptly it is carried out sound field and calculate and judge whether to satisfy seabed, sea filter criteria and whether arrive at apart from the border.When satisfying constraints, sound ray is carried out many way identifications, otherwise calculate initial glancing angle change step, change initial glancing angle and descend secondary tracking.The basic foundation of the many way identifications of sound ray be initial glancing angle symbol, sea surface reflection number of times, sub-bottom reflection number of times, on reverse number of times, the number of times that reverses down.After the many ways of sound ray identification, classification finishes, carry out the calculating that equivalent sound speed is pointed out in this reception.The situation of one secondary tracking as shown in Figure 4.

Specifically can be by following operation:

For given acoustic velocity distribution function c (z), if point sound source is positioned at P_s(r_s, z_s) locate, acoustic velocity is c_s, j bar sound ray is with initial glancing angle θ_sOutgoing, the arbitrfary point P on the sound ray (r, z) sound ray propagation trajectories and propagation time calculation expression are:

$r=r_s+{\&Integral;}_{z_s}^z\frac{\cos {\mathrm{\&theta;}}_s}{\sqrt{n^2\left(z\right)-{\mathrm{<figure-callout\; label="cos"\; filenames="HSA00000014240000012.png,HSA00000014240000041.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2{\mathrm{\&theta;}}_s}}\mathrm{dz}---\left(1\right)$

$t=\frac{1}{c_s}\&CenterDot;{\&Integral;}_{z_s}^z\frac{n^2\left(z\right)}{\sqrt{n^2\left(z\right)-{\mathrm{<figure-callout\; label="cos"\; filenames="HSA00000014240000012.png,HSA00000014240000041.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2{\mathrm{\&theta;}}_s}}\mathrm{dz}---\left(2\right)$

Wherein, refractive index$n\left(z\right)=\frac{c_s}{c\left(z\right)}.$

Arrive like this acceptance point (r, the equivalent velocity of sound of j bar sound ray z) can be tried to achieve:

${\stackrel{\&OverBar;}{c}}_j=\frac{\sqrt{{(r-r_s)}^2+{(z-z_s)}^2}}{t_j}---\left(3\right)$

3. after once initial glancing angle sound ray tracking finishes, change initial glancing angle according to initial glancing angle change step, repeatingstep 2; Finish until initial glancing angle useful space traversal.

4. the match of sound ray equivalence velocity of sound interpolation is arrived on all kinds of many ways, as shown in Figure 5.

5. obtain effective sound velocities by comparing all kinds of equivalent velocities of sound that arrive at sound ray in each spatial sampling point place, as shown in Figure 6.

6. the effective sound velocity of each sampled point that will obtain deposits matrix in, and the change sound source degree of depth, the acceptance point degree of depth can be set up two dimension or three-dimensional effective sound velocity matrix according to the step of front, as shown in Figure 7.

7. any 2 effective sound velocity is got the effective sound velocity matrix by looking in the underwater acoustic channel, carries out nearest two sampled points of sound field and judges index, and the interpolation match is obtained.To be positioned at 5m dark such as obtaining sound source, and it is dark that acceptance point is positioned at 30m, and horizontal range 205m is effective sound velocity at a distance, carries out nearest two sampled points of sound field and judge that index goes out the far away and 210m distant place effective sound velocity of 200m, and the interpolation match obtains 205m place effective sound velocity.

It should be noted that at last, above embodiment is only in order to describe technical scheme of the present invention rather than the present technique method is limited, the present invention can extend to other modification, variation, application and embodiment on using, and therefore thinks that all such modifications, variation, application, embodiment are in spirit of the present invention and teachings.

Claims (9)

1. based on the underwater acoustic channel effective sound velocity method of estimation of intrinsic sound ray apparent search, it is characterized in that:

(1) initialization basic parameter mainly comprises sea, submarine frontier characteristic initialization, and the vertical velocity of sound distributed-hierarchical quantification in ocean, acceptance point spatial sampling scope and sample rate, the initial glancing angle useful space are provided with;

(2) sound source outgoing sound ray is followed the tracks of by different glancing angles, when sound ray arrives at the acceptance point degree of depth it is carried out the judgement of energy constraint condition, carries out many way identifications and ask for the equivalent velocity of sound when sound ray satisfies the energy constraint condition;

(3) after initial glancing angle useful space self adaptation variable step traversal finishes, the match of sound ray equivalence velocity of sound interpolation is arrived on all kinds of many ways;

(4) all kinds of equivalent velocities of sound that arrive at sound ray of comparison level sample point obtain each effective sound velocity;

(5) be that parameter deposits each sampled point effective sound velocity in matrix with the sound source degree of depth, the acceptance point degree of depth and the two horizontal range, the change sound source degree of depth, the acceptance point degree of depth are set up two dimension or three-dimensional effective sound velocity matrix according to the step of front;

(6), look into and get the match of effective sound velocity matrix interpolation and obtain effective sound velocity any in the underwater acoustic channel at 2 according to propagation distance or time.

2. the underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent according to claim 1, it is characterized in that: described sound source outgoing sound ray is followed the tracks of by different glancing angles, be to take initial glancing angle useful space self adaptation variable step traversal mechanism, adjust the step-length that glancing angle changes when promptly utilizing the fructufy of at every turn following the tracks of.

3. the underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent according to claim 1 and 2, it is characterized in that: described energy constraint condition mainly comprises seabed, sea filter criteria, and is provided with apart from the border.

4. the underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent according to claim 1 and 2, it is characterized in that: described many way identifications be to the initial glancing angle of sound ray, sea sub-bottom reflection number of times, the number of times that reverses is added up up and down, judges its type.

5. the underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent according to claim 3, it is characterized in that: described many way identifications be to the initial glancing angle of sound ray, sea sub-bottom reflection number of times, the number of times that reverses is added up up and down, judges its type.

6. the underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent according to claim 1 and 2, it is characterized in that: described looking into got the match of effective sound velocity matrix interpolation to obtain effective sound velocity any in the underwater acoustic channel at 2 is according to propagation distance or time, the effective sound velocity matrix is carried out nearest two sampled points of sound field judge index, to this 2 effective sound velocity interpolations match.

7. the underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent according to claim 3, it is characterized in that: described looking into got the match of effective sound velocity matrix interpolation to obtain effective sound velocity any in the underwater acoustic channel at 2 is according to propagation distance or time, the effective sound velocity matrix is carried out nearest two sampled points of sound field judge index, to this 2 effective sound velocity interpolations match.

8. the underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent according to claim 4, it is characterized in that: described looking into got the match of effective sound velocity matrix interpolation to obtain effective sound velocity any in the underwater acoustic channel at 2 is according to propagation distance or time, the effective sound velocity matrix is carried out nearest two sampled points of sound field judge index, to this 2 effective sound velocity interpolations match.

9. the underwater acoustic channel effective sound velocity method of estimation based on the search of intrinsic sound ray apparent according to claim 5, it is characterized in that: described looking into got the match of effective sound velocity matrix interpolation to obtain effective sound velocity any in the underwater acoustic channel at 2 is according to propagation distance or time, the effective sound velocity matrix is carried out nearest two sampled points of sound field judge index, to this 2 effective sound velocity interpolations match.

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