阅读说明：本技术 一种海底应答器定位方法、系统、存储介质及应用 (Submarine transponder positioning method, system, storage medium and application ) 是由 王振杰 赵爽 聂志喜 李伟嘉 于 2020-07-25 设计创作，主要内容包括：本发明属于水下声学定位技术领域,公开了一种海底应答器定位方法、系统、存储介质及应用,精确测量GNSS天线和换能器之间的相对位置,测量船在海面上持续走航,GNSS对各时刻GNSS天线进行定位,利用GNSS天线和换能器之间的相对位置关系计算得到各时刻换能器坐标；根据声速信息和不同历元下声学信号传播时间数据,计算不同历元下换能器和水下应答器之间的斜距；构建联合海面换能器-海底应答器整体平差函数模型,对整体平差函数模型进行等效变换消参解算,基于最小二乘原理确定海底应答器准确位置。本发明结合水下定位实际,构建整体平差函数模型和相应参数估计,提供一种基于GNSS/声学技术的海底应答器高精度定位方法。(The invention belongs to the technical field of underwater acoustic positioning, and discloses a positioning method, a system, a storage medium and application of a submarine transponder, wherein the relative position between a GNSS antenna and a transducer is accurately measured, a measuring ship continuously navigates on the sea surface, the GNSS positions the GNSS antenna at each moment, and the relative position relationship between the GNSS antenna and the transducer is utilized to calculate and obtain the coordinate of the transducer at each moment; calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs; and constructing an integral adjustment function model combining the sea surface transducer and the seabed transponder, carrying out equivalent transformation parameter elimination calculation on the integral adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle. The invention provides a high-precision positioning method of a submarine transponder based on a GNSS/acoustic technology, which combines underwater positioning practice to construct an integral adjustment function model and corresponding parameter estimation.)

1. A subsea transponder locating method, comprising:

accurately measuring the relative position between the GNSS antenna and the transducer, continuously navigating the survey ship on the sea surface, positioning the GNSS antenna at each moment by the GNSS, and calculating the coordinate of the transducer at each moment by using the relative position relationship between the GNSS antenna and the transducer;

calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs;

and constructing an integral adjustment function model combining the sea surface transducer and the seabed transponder, carrying out equivalent transformation parameter elimination calculation on the integral adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle.

2. A method as claimed in claim 1, wherein the accurately measuring the relative position between the GNSS antenna and the transducer, the survey vessel continuously navigating on the sea surface, the GNSS locating the GNSS antenna at each time, and the calculating the coordinates of the transducer at each time using the relative positional relationship between the GNSS antenna and the transducer comprises:

(1) before the survey ship sails, the relative position between the GNSS antenna and the ship bottom transducer is accurately measured;

(2) the survey ship continuously navigates on the sea surface, the GNSS antenna gives coordinates at each moment by a high-precision GNSS positioning technology, and the coordinates of the transducer are calculated according to the relative position relation and attitude data between the GNSS antenna and the transducer.

3. A subsea transponder location method as set forth in claim 1 wherein said calculating the slant range between the transducer and the subsea transponder at different epochs based on the speed of sound information and the acoustic signal travel time data at different epochs comprises:

(1) calculating a weighted average sound velocity according to the sound velocity profile data;

(2) during the continuous sailing process of the measuring ship on the sea surface, a ship platform transmitter transmits an acoustic pulse signal to an underwater transponder through a transducer arranged at the bottom of the ship, the submarine transponder sends back a response acoustic pulse signal after receiving the signal, the time interval of the transponder receiving the two signals is obtained, and the distance between the transducer and the underwater transponder is calculated according to the propagation time and the acoustic velocity information.

4. The method of claim 1, wherein the constructing of the combined sea surface transducer-subsea transponder global adjustment function model, the performing of the equivalent transformation cancellation solution on the global adjustment function model, and the determining of the accurate position of the subsea transponder based on the least squares principle comprises:

(1) setting the coordinates of the sea surface transducer and the seabed transponder as parameters to be solved, and constructing an acoustic ranging observation equation by the geometric distance and the measuring slant distance between the sea surface transducer and the seabed transponder;

(2) the prior coordinate of the sea surface transducer is taken as a virtual observation value, and a virtual observation equation is constructed;

(3) carrying out equivalent transformation on the linearized observation equation, and eliminating the coordinate parameters of the sea surface transducer;

(4) and resolving the transformed observation equation based on the least square principle to obtain the coordinate of the submarine transponder.

5. A subsea transponder positioning method as set forth in claim 4 and further comprising:

(1) the method comprises the steps that the sea surface GNSS technology is used for positioning the coordinates of an energy converter, before a survey ship sails, the relative position between a GNSS antenna and the energy converter is accurately measured, the sea surface survey ship sails continuously, the GNSS is used for positioning the GNSS antenna at each moment, the coordinates of the GNSS antenna at each moment are given by the high-precision GNSS positioning technology, and the coordinates of the energy converter are resolved according to the relative position relation between the GNSS antenna and the energy converter;

(2) performing acoustic ranging;

(3) and (3) combining the sea surface transducer and the seabed transponder to realize the integral adjustment scheme.

6. The subsea transponder location method of claim 5, wherein the acoustic ranging embodiment comprises:

firstly, calculating a weighted average sound velocity according to sound velocity profile data;

secondly, the ship-borne transmitter transmits a pulse signal to the underwater transponder through the transducer arranged at the bottom of the ship, the transponder receives the signal and then sends back a response sound pulse signal, the ship-borne receiver records the time interval between the transmission signal and the response signal, and the distance between the ship and the transponder can be obtained through the propagation time and the sound speed information:

7. a subsea transponder positioning method as set forth in claim 4 wherein said combined surface transducer-subsea transponder ensemble settling scheme comprises:

firstly, the coordinate parameter of the transducer causes the acoustic ranging equation to change, and the acoustic ranging equation is linearized through a Taylor series expansion method, specifically:

in the formula (I), the compound is shown in the specification,the approximate coordinates of the transducer in the ith epoch are given by the high-precision GNSS positioning technology;

if the distance between the n epoch transducers and the transponder is measured, the observation equation is:

L₁＝A₁Φ_p+B₁Φ^d+_l1

in the formula, L₁Is an n-dimensional distance observation vector; a. the₁，B₁A design matrix representing dimensions n × 3 and n × 3 n; phi_pIs the three-dimensional unknown coordinates of the transponder; phi^dAre the three-dimensional coordinates of the transducer,_l1is a random error vector;

second, the position information of the transducer provided by the GNSS high-precision positioning technology is treated as a virtual observation as follows:

in the formula I_iIs a 3-dimensional coordinate observation vector, E_3×3Is a 3 x 3 identity matrix and,_diis a 3-dimensional random error vector;

the n epoch virtual observation equation can be expressed as:

L₂＝A₂Φ_p+B₂Φ^d+_l2

in the formula, L₂(l₁l₂…l_n) Is a 3 n-dimensional vector, A₂Is a 3 x 3 zero matrix, B₂Is a 3n x 3n block diagonal matrix, B₂＝blkdiag(E_3×3,E_3×3,…,E_3×3)，_l2The random error vector with 3n dimensions is used for constructing a sea surface-seabed combined adjustment equation system as follows:

AΦ_p+BΦ^d+_l＝L

wherein A, B are 4n × 3 and 4n × 3 n-dimensional coefficient matrices, and A ═ A₁A₂]^T，B＝[B₁B₂]^T(ii) a L is a 4 n-dimensional observation vector, L ═ L₁L₂]^T(ii) a Is an error vector of 4n dimension [, ]_{l1 l2}]^T；

And thirdly, carrying out equivalent transformation on the integral adjustment observation equation of the sea surface transducer and the seabed transponder, thereby eliminating the coordinate parameters of the sea surface transducer, and carrying out transponder coordinate calculation based on the least square principle:

the linearized observation equation system is re-expressed as:

wherein, P is an observation value weight matrix which is a 4n multiplied by 4n block diagonal matrix;

carrying out equivalent transformation on the linearized observation equation, and eliminating the coordinate parameters of the sea surface transducer:

L＝D₁Φ_p+U₁

in the formula

D₁＝(E-J)A

M₂₂＝B^TPB

In the formula of U₁An error vector of 4n dimensions;

estimating unknown parameters of the underwater transponder based on the least square principle:

8. a computer-readable storage medium storing a computer program which, when executed by a processor, causes the processor to perform the steps of:

accurately measuring the relative position between the GNSS antenna and the transducer, continuously navigating the survey ship on the sea surface, positioning the GNSS antenna at each moment by the GNSS, and calculating the coordinate of the transducer at each moment by using the relative position relationship between the GNSS antenna and the transducer;

calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs;

and constructing an integral adjustment function model combining the sea surface transducer and the seabed transponder, carrying out equivalent transformation parameter elimination calculation on the integral adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle.

9. A subsea transponder positioning system for implementing the subsea transponder positioning method of any of claims 1-7, the subsea transponder positioning system comprising:

the energy converter coordinate calculation module at each moment is used for accurately measuring the relative position between the GNSS antenna and the energy converter, the survey ship continuously navigates on the sea surface, the GNSS locates the GNSS antenna at each moment, and the energy converter coordinate at each moment is calculated by utilizing the relative position relation between the GNSS antenna and the energy converter;

the slant distance calculation module is used for calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs;

and the seabed transponder coordinate calculation module is used for constructing a combined sea surface transducer-seabed transponder overall adjustment function model, carrying out equivalent transformation parameter elimination calculation on the overall adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle.

10. A marine underwater positioning system equipped with a subsea transponder positioning system according to claim 9.

Technical Field

The invention belongs to the technical field of underwater acoustic positioning, and particularly relates to a positioning method and system of a submarine transponder, a storage medium and application.

Background

The underwater positioning technology plays an important role in marine activities, and is different from the satellite positioning technology on land in that electromagnetic waves cannot penetrate through a thick water layer and are seriously attenuated in water. In contrast, the sound wave has good characteristics in propagation in seawater, so that the sound wave is widely applied to various activities in the sea as a means for communication, navigation and monitoring. With the development of satellite communication technology, the method for performing combined positioning by using satellite positioning technology and underwater acoustic positioning is also successfully applied to marine activities such as marine exploration and development, geological resource investigation and the like.

At present, a sea surface survey ship circular navigation mode is mainly adopted for positioning the submarine transponder, the GNSS high-precision positioning technology is utilized for determining the coordinate of the transducer on the survey ship, intersection positioning is carried out according to acoustic ranging, and therefore the position of the submarine transponder is accurately determined. However, the traditional method neglects the position error of the transducer based on model simplification, and then limits the positioning accuracy of the transponder, and cannot meet the requirement of high-accuracy underwater positioning. Aiming at the problems existing in the traditional underwater sound positioning method, in order to better utilize the coordinate prior information of the transducer and improve the defects of the existing underwater positioning method, a balancing method which is more in line with the underwater positioning practice needs to be researched.

Through the above analysis, the problems and defects of the prior art are as follows: the traditional method ignores the position error of the transducer and reduces the positioning precision of the transponder.

The difficulty in solving the above problems and defects is: firstly, how to take the coordinate error of the transducer into consideration and construct a positioning model which fully takes the prior coordinate information of the transducer into consideration; secondly, parameterizing the coordinate of the transducer, and greatly increasing unknown parameters of an observation equation, thereby greatly increasing the calculation amount of adjustment calculation and reducing the calculation amount of adjustment by properly transforming the equation.

The significance of solving the problems and the defects is as follows: the method can take the position error of the transducer into consideration, fully utilize the prior coordinate information of the transducer, establish a sea surface transducer-seabed transponder integral adjustment positioning model which is consistent with the actual situation, weaken the error influence and improve the positioning precision of the seabed transponder.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a positioning method, a positioning system, a storage medium and application of a submarine transponder.

The invention is realized in such a way that a subsea transponder positioning method comprises:

accurately measuring the relative position between the GNSS antenna and the transducer, continuously navigating the survey ship on the sea surface, positioning the GNSS antenna at each moment by the GNSS, and calculating the coordinate of the transducer at each moment by using the relative position relationship between the GNSS antenna and the transducer;

calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs;

and constructing an integral adjustment function model combining the sea surface transducer and the seabed transponder, carrying out equivalent transformation parameter elimination calculation on the integral adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle.

Further, the accurate relative position between survey GNSS antenna and the transducer, survey the ship and continue to navigate on the sea, GNSS fixes a position the GNSS antenna at each moment, and it includes to utilize the relative position relation between GNSS antenna and the transducer to calculate the transducer coordinate at each moment:

(1) before the survey ship navigates, accurately measuring the relative position between the GNSS antenna and the ship bottom transducer;

(2) the survey ship continuously navigates on the sea surface, the GNSS antenna gives coordinates at each moment by a high-precision GNSS positioning technology, and the coordinates of the transducer are calculated according to the relative position relation and attitude data between the GNSS antenna and the transducer.

Further, the calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound speed information and the acoustic signal propagation time data under different epochs comprises:

(1) calculating a weighted average sound velocity according to the sound velocity profile data;

(2) during the continuous sailing process of the measuring ship on the sea surface, a ship platform transmitter transmits an acoustic pulse signal to an underwater transponder through a transducer arranged at the bottom of the ship, the submarine transponder sends back a response acoustic pulse signal after receiving the signal, the time interval of the transponder receiving the two signals is obtained, and the distance between the transducer and the underwater transponder is calculated according to the propagation time and the acoustic velocity information.

Further, the establishing of the integral adjustment function model combining the sea surface transducer and the seabed transponder, the equivalent transformation parameter elimination calculation of the integral adjustment function model, and the determining of the accurate position of the seabed transponder based on the least square principle comprises:

(1) setting the coordinates of the sea surface transducer and the seabed transponder as parameters to be solved, and constructing an acoustic distance observation equation by the geometric distance between the sea surface transducer and the seabed transponder and the measurement slant distance;

(2) the prior coordinate of the sea surface transducer is taken as a virtual observation value, and a virtual observation equation is constructed;

(3) carrying out equivalent transformation on the linearized observation equation, and eliminating the coordinate parameters of the sea surface transducer;

(4) and resolving the transformed observation equation based on the least square principle to obtain the coordinate of the submarine transponder.

Further comprising:

(1) the method comprises the steps that the sea surface GNSS technology is used for positioning the coordinates of an energy converter, before a survey ship sails, the relative position between a GNSS antenna and the energy converter is accurately measured, the sea surface survey ship sails continuously, the GNSS is used for positioning the GNSS antenna at each moment, the coordinates of the GNSS antenna at each moment are given by the high-precision GNSS positioning technology, and the coordinates of the energy converter are resolved according to the relative position relation between the GNSS antenna and the energy converter;

(2) performing acoustic ranging;

(3) and (3) combining the sea surface transducer and the seabed transponder to realize the integral adjustment scheme.

Further, the acoustic ranging implementation includes:

firstly, calculating a weighted average sound velocity according to sound velocity profile data;

secondly, a ship-borne transmitter transmits a pulse signal to an underwater transponder through a transducer arranged at the bottom of the ship, the transponder receives the signal and then sends back a response sound pulse signal, a ship-borne receiver records the time interval between the transmission signal and the reception of the response signal, and the distance between the ship and the transponder can be obtained through the propagation time and sound speed information;

further, the combined surface transducer-subsea transponder ensemble adjustment scheme comprises:

the method comprises the following steps that firstly, an acoustic ranging equation is changed due to introduction of transducer coordinate parameters, and linearization is carried out through a Taylor series expansion method, wherein the method specifically comprises the following steps:

in the formula (I), the compound is shown in the specification,

the approximate coordinates of the transducer in the ith epoch are given by the high-precision GNSS positioning technology;is the approximate coordinates of the subsea transponder;is the coordinate correction of the transducer at the ith epoch;

is the coordinate correction of the transponder; a is_i,b_iFirst order partial derivatives corresponding to the transponder coordinates and transducer coordinates, respectively;

representing a geometric distance;_ρviis the system in which the ith epoch is related to the speed of soundAn error;_ρtiis the system error of the ith epoch with respect to time;_iis the ith epoch random error.

If the distance between the n epoch transducers and the transponder is measured, the observation equation is:

L₁＝A₁Φ_p+B₁Φ^d+_l1

in the formula, L₁Is an n-dimensional distance observation vector; a. the₁，B₁A design matrix representing dimensions n × 3 and n × 3 n; phi_pIs the three-dimensional unknown coordinates of the transponder; phi^dAre the three-dimensional coordinates of the transducer,_l1is a random error vector.

Second, the position information of the transducer provided by the GNSS high-precision positioning technology is treated as a virtual observation as follows:

in the formula I_iIs a 3-dimensional coordinate observation vector, E_3×3Is a 3 x 3 identity matrix and,_diis a 3-dimensional random error vector;

the n epoch virtual observation equation is:

L₂＝A₂Φ_p+B₂Φ^d+_l2

in the formula, L₂(l₁l₂…l_n) Is a 3 n-dimensional vector, A₂Is a 3 x 3 zero matrix, B₂Is a 3n x 3n block diagonal matrix, B₂＝blkdiag(E_3×3,E_3×3,…,E_3×3)，_l2Is a random error vector with 3n dimensions, and the obtained sea surface-seabed combined adjustment equation system is as follows:

AΦ_p+BΦ^d+_l＝L

wherein A, B are 4n × 3 and 4n × 3 n-dimensional coefficient matrices, and A ═ A₁A₂]^T，B＝[B₁B₂]^T(ii) a L is a 4 n-dimensional observation vector L ═ L₁L₂]^T(ii) a Is an error of 4n dimensionsVector, and_{l1 l2}]^T；

and thirdly, carrying out equivalent transformation on the integral adjustment observation equation of the sea surface transducer and the seabed transponder, thereby eliminating the coordinate parameters of the sea surface transducer, and carrying out transponder coordinate calculation based on the least square principle:

the linearized observation equation system is re-expressed as:

wherein, P is an observation value weight matrix which is a 4n multiplied by 4n block diagonal matrix;

carrying out equivalent transformation on the linearized observation equation, and eliminating the coordinate parameters of the sea surface transducer:

L＝D₁Φ_p+U₁

in the formula

D₁＝(E-J)A

M₂₂＝B^TPB

In the formula of U₁Is an error vector of 4n dimensions.

Estimating unknown parameters of the underwater transponder based on the least square principle:

it is another object of the present invention to provide a computer-readable storage medium, stored with a computer program, which, when executed by a processor, causes the processor to perform the steps of:

accurately measuring the relative position between the GNSS antenna and the transducer, continuously navigating the survey ship on the sea surface, positioning the GNSS antenna at each moment by the GNSS, and calculating the coordinate of the transducer at each moment by using the relative position relationship between the GNSS antenna and the transducer;

calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs;

and constructing an integral adjustment function model combining the sea surface transducer and the seabed transponder, carrying out equivalent transformation parameter elimination calculation on the integral adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle.

It is another object of the present invention to provide a subsea transponder positioning system implementing the subsea transponder positioning method, the subsea transponder positioning system comprising:

the energy converter coordinate calculation module at each moment is used for accurately measuring the relative position between the GNSS antenna and the energy converter, the survey ship continuously navigates on the sea surface, the GNSS locates the GNSS antenna at each moment, and the energy converter coordinate at each moment is calculated by utilizing the relative position relation between the GNSS antenna and the energy converter;

the slant distance calculation module is used for calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs;

and the seabed transponder coordinate calculation module is used for constructing a combined sea surface transducer-seabed transponder overall adjustment function model, carrying out equivalent transformation parameter elimination calculation on the overall adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle.

It is another object of the present invention to provide a marine underwater positioning system incorporating the subsea transponder positioning system.

By combining all the technical schemes, the invention has the advantages and positive effects that: the invention provides a high-precision positioning method of a submarine transponder based on a GNSS/acoustic technology, which combines underwater positioning practice to construct a function model of integral adjustment and parameter estimation. The method combines the underwater positioning practice, calculates the slant distance between the sea surface transducer and the seabed transponder under different epochs by weighting the average sound velocity and the acoustic signal propagation time data under different epochs; the coordinate of the sea surface transducer and the coordinate of the seabed transponder are set as parameters to be solved, an integral adjustment function model combining the sea surface transducer and the seabed transponder is constructed by the geometric distance between the sea surface transducer and the seabed transponder and the measuring slant distance, parameter elimination processing is carried out on the integral adjustment function model through equivalent transformation based on the least square principle, the coordinate parameter of the transducer is eliminated, the coordinate of the seabed transponder is solved based on the least square principle, higher underwater positioning precision can be obtained compared with the traditional adjustment function model, the underwater positioning result is improved, and the underwater positioning method has certain application value in various aspects such as seabed control point arrangement in deep and far sea areas, ocean ground reference network construction, seabed crust deformation monitoring and the like.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained from the drawings without creative efforts.

Fig. 1 is a flow chart of a subsea transponder locating method provided by an embodiment of the present invention.

FIG. 2 is a schematic structural diagram of a subsea transponder locating system provided by an embodiment of the present invention;

in fig. 2: 1. a transducer coordinate calculation module at each moment; 2. an incline distance calculating module; 3. and a submarine transponder accurate position determination module.

Fig. 3 is a flowchart of an implementation of a subsea transponder locating method according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of underwater acoustic positioning based on a survey vessel provided by an embodiment of the invention.

Fig. 5 is a schematic diagram of a typical Munk sound velocity profile provided by an embodiment of the present invention.

Fig. 6 is a comparison diagram of positioning accuracy of the conventional adjustment method and the new method provided by the embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In view of the problems in the prior art, the present invention provides a subsea transponder positioning method, system, storage medium and use thereof, and the present invention is described in detail below with reference to the accompanying drawings.

As shown in fig. 1, the method for locating a subsea transponder according to the present invention comprises the following steps:

s101: accurately measuring the relative position between the GNSS antenna and the transducer, continuously navigating the survey ship on the sea surface, positioning the GNSS antenna at each moment by the GNSS, and calculating the coordinate of the transducer at each moment by using the relative position relationship between the GNSS antenna and the transducer;

s102: calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs;

s103: and constructing an integral adjustment function model combining the sea surface transducer and the seabed transponder, carrying out equivalent transformation parameter elimination calculation on the integral adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle.

Those skilled in the art of the method for locating a subsea transponder according to the present invention may also perform other steps, and the method for locating a subsea transponder according to the present invention of fig. 1 is only one specific example.

As shown in fig. 2, the present invention provides a subsea transponder positioning system comprising:

the energy converter coordinate calculation module 1 at each moment is used for accurately measuring the relative position between the GNSS antenna and the energy converter, continuously navigating the survey ship on the sea surface, positioning the GNSS antenna at each moment by the GNSS, and calculating the energy converter coordinate at each moment by using the relative position relation between the GNSS antenna and the energy converter;

the slant distance calculation module 2 is used for calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs;

and the accurate position determining module 3 of the submarine transponder is used for constructing a combined sea surface transducer-submarine transponder overall adjustment function model, carrying out equivalent transformation parameter elimination calculation on the overall adjustment function model, and determining the accurate position of the submarine transponder based on the least square principle.

The technical solution of the present invention is further described below with reference to the accompanying drawings.

As shown in fig. 3, the method for locating a subsea transponder according to the present invention comprises the following steps:

s1, accurately measuring the relative position between the GNSS antenna and the transducer, continuously navigating on the sea surface by the measuring ship, positioning the GNSS antenna at each moment by the GNSS, and calculating the coordinate of the transducer at each moment by using the relative position relationship between the GNSS antenna and the transducer, wherein the specific process comprises the following steps:

s1.1, accurately measuring the relative position between a GNSS antenna and a ship bottom transducer before a measuring ship navigates;

s1.2, the survey ship continuously navigates on the sea surface, coordinates of the GNSS antenna are given by a high-precision GNSS positioning technology at each moment, and the coordinates of the transducer are calculated according to the relative position relation and attitude data between the GNSS antenna and the transducer.

S2, calculating the slant distance between the transducer and the underwater transponder under different epochs according to the sound velocity information and the acoustic signal propagation time data under different epochs; the specific process comprises the following steps:

s2.1, calculating a weighted average sound velocity according to the sound velocity profile data;

s2.2, in the process of measuring that the ship continuously sails on the sea surface, a ship platform transmitter transmits an acoustic pulse signal to an underwater transponder through a transducer arranged at the bottom of the ship, the submarine transponder sends back a response acoustic pulse signal after receiving the signal to obtain the time interval of the transponder receiving the two signals, and the distance between the transducer and the underwater transponder is calculated according to the propagation time and the acoustic velocity information.

S3, constructing a combined sea surface transducer-seabed transponder overall adjustment function model, carrying out equivalent transformation parameter elimination calculation on the overall adjustment function model, and determining the accurate position of the seabed transponder based on the least square principle, wherein the specific process comprises the following steps;

s3.1, setting the coordinates of the sea surface transducer and the seabed transponder as parameters to be solved, and constructing an acoustic distance observation equation by the geometric distance between the sea surface transducer and the seabed transponder and the measurement slant distance;

s3.2, taking the prior coordinate of the sea surface transducer as a virtual observation value, and constructing a virtual observation equation;

s3.3, performing equivalent transformation on the linear observation equation, and eliminating the coordinate parameters of the sea surface transducer;

and S3.4, resolving the transformed observation equation based on the least square principle to obtain the coordinate of the submarine responder. The specific embodiment comprises the following steps:

1. sea-surface GNSS technology locates the transducer coordinates. Before the survey vessel sails, the relative position between the GNSS antenna and the transducer is accurately measured, the sea surface survey vessel sails continuously, the GNSS positions the GNSS antenna at each moment, coordinates of the GNSS antenna at each moment are given by a high-precision GNSS positioning technology, and the coordinates of the transducer are resolved according to the relative position relation between the GNSS antenna and the transducer;

2. an acoustic ranging implementation.

Firstly, calculating a weighted average sound velocity according to sound velocity profile data;

secondly, the ship-borne transmitter transmits a pulse signal to the underwater transponder through the transducer arranged at the bottom of the ship, the transponder receives the signal and then sends back a response sound pulse signal, the ship-borne receiver records the time interval between the transmission signal and the response signal, and the distance between the ship and the transponder can be obtained through the propagation time and the sound speed information:

3. and (3) combining the sea surface transducer and the seabed transponder to realize the integral adjustment scheme.

Firstly, the coordinate parameter of the transducer causes the acoustic ranging equation to change, and the acoustic ranging equation is linearized through a Taylor series expansion method, specifically:

in the formula (I), the compound is shown in the specification,the approximate coordinates of the transducer in the ith epoch are given by the high-precision GNSS positioning technology;is the approximate coordinates of the subsea transponder;is the coordinate correction of the transducer at the ith epoch;

is the coordinate correction of the transponder; a is_i,b_iFirst order partial derivatives corresponding to the transponder coordinates and transducer coordinates, respectively;representing a geometric distance; rho_viIs the system error of the ith epoch related to the speed of sound; rho_tiIs the system error of the ith epoch with respect to time;_iis the ith epoch random error.

If the distance between the n epoch transducers and the transponders is measured, the matrix equation is constructed as:

L₁＝A₁Φ_p+B₁Φ^d+_l1

in the formula, L₁Is an n-dimensional distance observation vector; a. the₁，B₁A design matrix representing dimensions n × 3 and n × 3 n; phi_pIs the three-dimensional unknown coordinates of the transponder; phi^dAre the three-dimensional coordinates of the transducer,_l1is a random error vector.

Second, the position information of the transducer provided by the GNSS high-precision positioning technology is treated as a virtual observation as follows:

in the formula I_iIs a 3-dimensional coordinate observation vector, E_3×3Is a 3 x 3 identity matrix and,_diis a 3-dimensional random error vector;

the matrix expression of the n epoch virtual observation equations is constructed as follows:

L₂＝A₂Φ_p+B₂Φ^d+_l2

in the formula, L₂(l₁l₂…l_n) Is a 3 n-dimensional zero vector, A₂Is a 3 x 3 zero matrix, B₂Is a 3n x 3n block diagonal matrix, B₂＝blkdiag(E_3×3,E_3×3,…,E_3×3)，_l2The random error vector is 3 n-dimensional, and the sea surface-seabed combined adjustment equation system is established as follows:

AΦ_p+BΦ^d+_l＝L

wherein A, B are 4n × 3 and 4n × 3 n-dimensional coefficient matrices, and A ═ A₁A₂]^T，B＝[B₁B₂]^T(ii) a L is a 4 n-dimensional observation vector L ═ L₁L₂]^T(ii) a Is an error vector of 4n dimensions,_l＝[_{l1 l2}]^T；

and thirdly, carrying out equivalent transformation on the integral adjustment observation equation of the sea surface transducer and the seabed transponder, thereby eliminating the coordinate parameters of the sea surface transducer, and carrying out transponder coordinate calculation based on the least square principle:

the linearized observation equation system is re-expressed as:

wherein, P is an observation value weight matrix which is a 4n multiplied by 4n block diagonal matrix;

carrying out equivalent transformation on the linearized observation equation, and eliminating the coordinate parameters of the sea surface transducer:

L＝D₁Φ_p+U₁

in the formula

D₁＝(E-J)A

M₂₂＝B^TPB

In the formula of U₁Is an error vector of 4n dimensions.

Estimating unknown parameters of the underwater transponder based on the least square principle:

the technical effects of the present invention will be described in detail with reference to the tests below.

According to a designed route, four different water depth environments of 100m, 500m, 1000m and 3000m are combined, simulation experiments are respectively carried out for 500 times, and then the underwater positioning accuracy of the traditional method and the underwater positioning accuracy of the invention are compared.

As shown in fig. 6, the test shows that the traditional least square adjustment method and the positioning result of the invention have obvious difference. The underwater positioning accuracy of the traditional method is respectively 0.088m, 0.188m, 0.306m and 0.676m, the underwater positioning accuracy of the invention is respectively 0.066m, 0.155m, 0.248m and 0.545m, and the positioning accuracy is respectively improved by 25.0%, 17.6%, 19.0% and 19.4%.

In conclusion, the method combines the underwater positioning practice, calculates the slant distance between the sea surface transducer and the seabed transponder under different epochs by weighting the average sound velocity and the acoustic signal propagation time data under different epochs; the coordinate of the sea surface transducer and the coordinate of the seabed transponder are set as parameters to be solved, an integral adjustment function model combining the sea surface transducer and the seabed transponder is constructed by the geometric distance and the measuring slant distance between the sea surface transducer and the seabed transponder, parameter elimination processing is carried out on the integral adjustment function model through equivalent transformation based on the least square principle, the coordinate parameter of the transducer is eliminated, the coordinate of the seabed transponder is solved based on the least square principle, and higher underwater positioning precision can be obtained compared with the traditional adjustment function model. Improves the underwater positioning result and has certain application value.

It should be noted that the embodiments of the present invention can be realized by hardware, software, or a combination of software and hardware. The hardware portion may be implemented using dedicated logic; the software portions may be stored in a memory and executed by a suitable instruction execution system, such as a microprocessor or specially designed hardware. Those skilled in the art will appreciate that the apparatus and methods described above may be implemented using computer executable instructions and/or embodied in processor control code, such code being provided on a carrier medium such as a disk, CD-or DVD-ROM, programmable memory such as read only memory (firmware), or a data carrier such as an optical or electronic signal carrier, for example. The apparatus and its modules of the present invention may be implemented by hardware circuits such as very large scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., or by software executed by various types of processors, or by a combination of hardware circuits and software, e.g., firmware.

The above description is only for the purpose of illustrating the present invention and the appended claims are not to be construed as limiting the scope of the invention, which is intended to cover all modifications, equivalents and improvements that are within the spirit and scope of the invention as defined by the appended claims.