CN117420504B - A hybrid baseline hydroacoustic positioning system - Google Patents

Abstract

The application discloses hybrid baseline underwater sound positioning system belongs to the positioning field under water, and this system includes: the transmitting transducer is used for sending an inquiry sound signal to the transponder; the transponder is placed on an underwater target to be positioned, and is used for transmitting a response sound signal corresponding to the query sound signal under the condition that the response sound signal transmitted by the transmitting transducer is received; the ultra-short baseline array comprises a plurality of receiving hydrophones which are separately arranged with the transmitting transducer, and is used for receiving response sound signals replied by the transponder and calculating first position information of the transponder according to the received response sound signals; the short baseline array comprises a plurality of ultra-short baseline arrays, and is used for receiving response sound signals replied by the transponder and calculating second position information of the transponder according to the received response sound signals; the short baseline array is used for fusing the first position information and the second position information and calculating to obtain final position information of the transponder.

Description

A hybrid baseline hydroacoustic positioning system

Technical field

This application belongs to the field of underwater positioning, and specifically relates to a hybrid baseline underwater acoustic positioning system.

Background technique

Underwater inertial navigation positioning, Doppler Velocity Log (DVL) velocity positioning, hydroacoustic positioning (Ultra-Short Baseline, USBL), Short Baseline (SBL), Long Baseline (LBL) )) and other technologies have their own advantages in the field of underwater positioning, and each also has some limitations.

Due to the accumulation of measurement errors and integration errors in underwater inertial navigation positioning, the positioning accuracy of the inertial navigation system will gradually decrease over time. This is one of the major challenges for inertial navigation systems, especially during long underwater missions.

Although DVL speed positioning is highly practical in underwater navigation, its positioning range is usually limited by water conditions and water flow speed. In some cases, DVL may need to be used in conjunction with other positioning systems to compensate for its limitations in certain aspects.

For hydroacoustic positioning technology, the conventional USBL system usually integrates the transmitting transducer and the receiving hydrophone at the water surface node. The receiving matrix size is small, which reduces the accuracy of positioning; while the SBL system increases the baseline length At the same time, its formation layout and calibration are more difficult; the LBL system involves arranging hydroacoustic transmitting transducers and receiving hydrophones underwater and on the water surface, as well as installing buoys or fixed equipment, which may require complex operations. Secondly, Longer baselines may increase relative position changes between underwater devices, which may reduce positioning stability in some cases.

To sum up, it is difficult for relevant underwater positioning technology to achieve long-term, high-precision real-time positioning requirements underwater.

Contents of the invention

Embodiments of the present application provide a hybrid baseline hydroacoustic positioning system, which can solve the problem that underwater positioning technology is difficult to achieve long-term, high-precision real-time positioning requirements underwater.

In a first aspect, embodiments of the present application provide a hybrid baseline hydroacoustic positioning system, which includes: a transmitting transducer, a transponder, an ultra-short baseline array, and a short baseline array; the transmitting transducer is used to detect the The transponder sends an interrogation sound signal; the transponder is placed on the underwater target to be located, and the transponder is used to transmit the interrogation sound signal when receiving the interrogation sound signal sent by the transmitting transducer. The response sound signal corresponding to the inquiry signal; the ultra-short baseline array includes a plurality of receiving hydrophones, and the plurality of receiving hydrophones are arranged separately from the transmitting transducer. The ultra-short baseline array is used for Receive the response sound signal returned by the transponder, and calculate the first position information of the transponder according to the received response sound signal; the short baseline array includes a plurality of the ultra-short baseline arrays, and the short baseline array The array is used to receive the response sound signal returned by the transponder, and calculate the second position information of the transponder based on the received response sound signal; the short baseline array is used to compare the first position information and the The second position information is fused to obtain the final position information of the transponder.

In the embodiment of this application, the hybrid baseline hydroacoustic positioning system includes: a transmitting transducer, a transponder, an ultra-short baseline array and a short baseline array; the transmitting transducer is used to send an interrogation signal to the transponder; the transponder is placed on On the underwater target to be located, the transponder is used to transmit a response sound signal corresponding to the inquiry sound signal sent by the transmitting transducer; the ultra-short baseline array includes multiple receiving hydrophones , multiple receiving hydrophones and transmitting transducers are deployed separately, making the ultra-short baseline array larger and improving positioning accuracy. The ultra-short baseline array is used to receive the response acoustic signal returned by the transponder. According to the received The response sound signal is used to calculate the first position information of the transponder; the short baseline array includes multiple ultra-short baseline arrays, and the short baseline array is used to receive the response sound signal returned by the transponder, and based on the received response sound signal, the answer is calculated The second position information of the transponder; the short baseline array is used to fuse the first position information and the second position information, and the final position information of the transponder is obtained. The first position information of the transponder is solved by the ultra-short baseline array. Data fusion of position information and the second position information of the transponder calculated by the short baseline array can reduce the impact of errors in various measurement links such as delay and phase on the positioning results, improve positioning reliability and accuracy, and obtain the final optimal positioning result. location information.

Description of the drawings

Figure 1 is a schematic diagram of the overall composition of a hybrid baseline underwater acoustic positioning system provided by an embodiment of the present application;

Figure 2 is a schematic diagram of the positioning process of a hybrid baseline hydroacoustic positioning system provided by an embodiment of the present application;

Figure 3 is a schematic diagram of the distribution of receiving hydrophones of an ultra-short baseline array provided by an embodiment of the present application;

Figure 4 is a schematic diagram of a short baseline array provided by an embodiment of the present application.

Explanation of reference symbols:

10-transmitting transducer, 11-transponder, 12-ultra-short baseline array, 13-short baseline array, 14-receiving hydrophone, 15-underwater transponder array.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

The terms "first", "second", etc. in the description and claims of this application are used to distinguish similar objects and are not used to describe a specific order or sequence. It is to be understood that the figures so used are interchangeable under appropriate circumstances so that the embodiments of the present application can be practiced in orders other than those illustrated or described herein, and that "first," "second," etc. are distinguished Objects are usually of one type, and the number of objects is not limited. For example, the first object can be one or multiple. In addition, "and/or" in the description and claims indicates at least one of the connected objects, and the character "/" generally indicates that the related objects are in an "or" relationship.

The hybrid baseline underwater acoustic positioning system provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings through specific embodiments and application scenarios.

Figure 1 shows a schematic diagram of the overall composition of a hybrid baseline hydroacoustic positioning system provided by an embodiment of the present application. As shown in Figure 1, the hybrid baseline hydroacoustic positioning system includes a transmitting transducer 10, a transponder 11, and an ultra-short baseline array. 12 and short baseline array 13; the transmitting transducer 10 is used to send an interrogation sound signal to the transponder 11; the transponder 11 is placed on the underwater target to be located, and the transponder 11 is used to When receiving the inquiry sound signal sent by the transmitting transducer 10, a response sound signal corresponding to the inquiry sound signal is transmitted; the ultra-short baseline array 12 includes a plurality of receiving hydrophones 14, and multiple The receiving hydrophones 14 are deployed separately from the transmitting transducer 10. The ultra-short baseline array 12 is used to receive the response acoustic signal returned by the transponder 11. According to the received response acoustic signal, the solution Calculate the first position information of the transponder 11; the short baseline array 13 includes a plurality of the ultra-short baseline arrays 12, and the short baseline array 13 is used to receive the response sound signal returned by the transponder 11, according to The received response sound signal is used to calculate the second position information of the transponder 11; the short baseline array 13 is used to fuse the first position information and the second position information, and the second position information of the transponder 11 is calculated to obtain the The final position information of the transponder 11.

Specifically, the hybrid baseline hydroacoustic positioning system consists of several transmitting transducers 10 , transponders 11 , and receiving hydrophones 14 . The transmitting transducer 10 is generally installed several meters below the water surface, actively transmits an interrogation sound signal, and initiates an inquiry to the transponder 11 to be located underwater. The transponder 11 is placed on the underwater target to be located. The transponder 11 receives the interrogation sound signal, determines whether it should respond, and transmits the corresponding response sound signal according to the protocol. The receiving hydrophone 14 is placed several meters below the water surface, generally at the same position as the transmitting transducer 10, to receive the response acoustic signal emitted by the underwater transponder 11, and to calculate the position of the underwater transponder 11 at the acoustic head. information.

As shown in Figure 1, different from the conventional ultra-short baseline, in the embodiment of the present application, the transmitting transducer 10 and the receiving hydrophone 14 of the USBL acoustic head are arranged separately, and the transmitting transducer 10 is arranged separately, and multiple receivers The ultra-short baseline array 12 composed of hydrophones 14 is arranged at a certain distance from each other near the water surface to form a short baseline array 13 . Multiple receiving hydrophones 14 and transmitting transducers 10 are arranged separately, making the scale of the ultra-short baseline array 12 larger and improving positioning accuracy.

In the embodiment of this application, the hybrid baseline hydroacoustic positioning system includes: a transmitting transducer, a transponder, an ultra-short baseline array and a short baseline array; the transmitting transducer is used to send an interrogation signal to the transponder; the transponder is placed on On the underwater target to be located, the transponder is used to transmit a response sound signal corresponding to the inquiry sound signal sent by the transmitting transducer; the ultra-short baseline array includes multiple receiving hydrophones , multiple receiving hydrophones and transmitting transducers are deployed separately, making the ultra-short baseline array larger and improving positioning accuracy. The ultra-short baseline array is used to receive the response acoustic signal returned by the transponder. According to the received The response sound signal is used to calculate the first position information of the transponder; the short baseline array includes multiple ultra-short baseline arrays, and the short baseline array is used to receive the response sound signal returned by the transponder, and based on the received response sound signal, the answer is calculated The second position information of the transponder; the short baseline array is used to fuse the first position information and the second position information, and the final position information of the transponder is obtained. The first position information of the transponder is solved by the ultra-short baseline array. Data fusion of position information and the second position information of the transponder calculated by the short baseline array can reduce the impact of errors in various measurement links such as delay and phase on the positioning results, improve positioning reliability and accuracy, and obtain the final optimal positioning result. location information.

In the embodiment of the present application, multiple receiving hydrophones 14 of the same ultra-short baseline array 12 are at different depths in the target axis direction. That is, the above-mentioned ultra-short baseline array 12 is characterized by multiple hydrophones at different depths on the z-axis, which can increase the working opening angle of the system.

In the embodiment of the present application, the number of transponders 11 may be one or more. In the case where the number of transponders 11 is multiple, the multiple transponders 11 are arranged on the underwater target to be located according to a preset geometric pattern. , as shown in Figure 1, multiple transponders 11 can form an underwater transponder array. Each transponder 11 is allocated a different exclusive response sound signal. The geometric figure can be a rectangle or a square. The above geometric figure is not specifically limited here. Each transponder 11 is allocated a different exclusive response sound signal to distinguish different transponder 11.

In the embodiment of the present application, the ultra-short baseline array 12 is used to calculate the first position information of the transponder 11 based on the ultra-short baseline positioning algorithm and the received response sound signal. The short baseline array 13 is used to calculate the second position information of the transponder 11 based on the short baseline positioning algorithm and the received response sound signal. The short baseline array 13 is used to fuse the first position information and the second position information according to the geometric position relationship constraints corresponding to the transponder 11 to obtain the final target position information.

Specifically, the positioning process diagram of the hybrid baseline hydroacoustic positioning system is shown in Figure 2. The positioning process of the hybrid baseline hydroacoustic positioning system includes:

The transmitting transducer sends the inquiry sound signal, and the underwater transponder receives the inquiry sound signal. Each underwater transponder sends a response sound signal. Each receiving hydrophone receives the response sound signal. Each receiving hydrophone array resolves the underwater transponder position. Perform USBL positioning and SBL positioning respectively to obtain the position of each underwater transponder. According to the geometric position relationship constraints of each transponder, data fusion is performed on the position of each underwater transponder, and then the optimal positioning solution is obtained, and the final target position information is obtained.

Specifically, the algorithm steps for solving the final target position information are as follows:

The first step: The ultra-short baseline array composed of each receiving hydrophone on the water surface is based on the USBL positioning principle to calculate the first position information of each underwater transponder.

Step 2: Based on the short baseline array composed of multiple ultra-short baseline arrays, apply the SBL positioning algorithm to solve the second position information of each underwater transponder.

Step 3: Under the constraints of the geometric position relationship of each underwater transponder, perform data fusion on the transponder position estimation results solved in the first and second steps to reduce errors in various measurement links such as delay and phase to position the results. influence, improve reliability and accuracy, and obtain the final target position information with optimal positioning.

Specifically, the specific scenario targeted by the embodiments of this application is underwater positioning. It is assumed that the number of surface units (receiving hydrophones) of the ultra-short baseline array is M (M is greater than 2), and the number of transponder units is N (can be 1). A transmitting transducer, M water surface receiving hydrophones, and N transponders.

Relative water surface coordinate center , the position of each underwater unit is (/> ,/> ,/> ),/> ...the coordinate center of each ultra-short baseline/> ,/> ...The water surface attitude angle in the absolute coordinate system relative to the water surface is ( ,/> ,/> ),/> ...The location of each underwater unit is (/> ,/> ,/> )/> ……/> ...relative to the underwater coordinate center/> , the position of each underwater transponder is (/> ,/> ,/> ), ...The underwater attitude angle relative to the underwater absolute coordinate system is (/> ,/> ,/> )/> ……/> and/> There is only translation, there is no rotation when the water surface and underwater absolute coordinate systems are defined.

According to the combined positioning of ultra-short baseline and short baseline, it can be obtained Position estimation of each underwater transponder unit in the coordinate system/> ,/> ,/> .

The following algorithm steps assume that the number of receiving hydrophones in the ultra-short baseline array is M=4, the number of underwater transponders is N=4, and the first underwater transponder unit is taken as an example. The details are as follows:

1. Ultra-short baseline (USBL) array element design:

As shown in Figure 3, each receiving hydrophone in the ultra-short baseline array ( ,/> ,/> ,/> ) are all spaced b, array elements ,/> ,/> ,/> Their respective coordinates are:

;

Available:

,/> , .

2. USBL underwater positioning solution:

The distribution pattern of each unit in each ultra-short baseline array is shown in Figure 3. The coordinate center of each ultra-short baseline , ...The water surface attitude angle in the absolute coordinate system relative to the water surface is (/> ,/> ,/> ), …

The coordinates of the target can be expressed as .

in It is the angle between the straight line connecting the ultra-short baseline emission source and the target and the x-axis, /> is the angle between the straight line connecting the ultra-short baseline emission source and the target and the z-axis, and S is the length of the straight line connecting the ultra-short baseline emission source and the target. With ultra-short baseline/> For example, coordinate center/> , the coordinate system water surface attitude angle is (/> ,/> ,/> ). Available:

=/> +/> +(/> (1)

=/> +(/> )/> (2)

=/> +/> +(/> (3)

because ,/> ,/> are all known, and the spacing b of each receiving hydrophone in the ultra-short baseline array is known, it can be obtained according to the above formula/> ,/> . The position of the underwater transponder unit can be obtained as (/> ,/> ,/> )Right now:

(4)

(5)

(6)

The number of water surface receiving hydrophones in each ultra-short baseline array is 4. According to the above formula, for each underwater transponder unit, 4 ultra-short baselines can be used to obtain 4 positions ( ,/> ,/> ), (/> ,/> ,/> ), (/> ,/> , ), (/> ,/> ,/> ).

The position measured by the ultrashort baseline array is modeled as . For the four measured position coordinates of the ultra-short baseline array:

( ,/> ,/> ), (/> ,/> ,/> ), (/> ,/> ,/> ), (/> ,/> ,/> ) can obtain the following four equations:

(7)

(8)

(9)

(10)

Arranging these equations into matrix form gives:

(11)

Among them, Z= ,X=/> ,/> ,/> ;

This linear system is then solved by the least squares method, that is, minimizing the sum of squares of the residuals The optimal parameters can be obtained/> :

(12)

After solving After that, use the final parameters/> The final position result after fitting is obtained, that is, the above-mentioned first position system information.

(13)

In the formula, is the final position result after fitting, that is, the above-mentioned first position information,/> are the parameters obtained by least squares solution.

3. SBL underwater positioning solution:

The SBL array is shown in Figure 4. From the above phase difference formula, the target position can be obtained as:

(14)

(15)

(16)

The positions of x and y can be obtained as:

(17)

(18)

(19)

In the formula, Obtained from the weighted average of four ultra-short baseline depth values, the final /> It is obtained from the ultra-short baseline least squares fitting results, that is:

(20)

4. Fusion of USBL and SBL underwater positioning results:

For ultra-short baseline coordinates ,/> The obtained position (/> ,/> ,/> ) after coordinate transformation ,/> Convert to/> The coordinates under (/> ,/> ,/> ).

Finally, the four target positions obtained from the ultra-short baseline and the target positions obtained from the short baseline are summed and averaged to obtain the final target position ( ,/> ,/> ).

(twenty one)

(twenty two)

(twenty three)

The hybrid baseline hydroacoustic positioning system provided by the embodiment of the present application separates the array of USBL transmitting transducers and receiving hydrophones on the water surface, and multiple receiving hydrophones and transmitting transducers are deployed separately, so that The larger scale of the ultra-short baseline array improves positioning accuracy. Optimize the design of the array composed of USBL receiving hydrophones. The z-axis coordinates of the four array elements are different. This increases the aperture in the vertical direction, improves the vertical resolution, accurately captures the differences in the vertical direction of the hydroacoustic signal, and improves the Positioning accuracy of underwater transponders. The hybrid baseline positioning method of USBL and SBL is used to receive data from an array composed of receiving hydrophones. The positioning solution is performed based on the principles of USBL and SBL, and the calculated position information of the underwater transponder is constrained by the geometric position relationship of the transponder. Data fusion (taking the least squares method as an example) can improve positioning accuracy.

Claims (2)

1. A hybrid baseline underwater acoustic positioning system, characterized by including a transmitting transducer, a transponder, an ultra-short baseline array and a short baseline array; The transmitting transducer is used to send an inquiry sound signal to the transponder; The transponder is placed on the underwater target to be located, and the transponder is used to transmit a response sound signal corresponding to the interrogation sound signal when receiving the interrogation sound signal sent by the transmitting transducer. ; The ultra-short baseline array includes a plurality of receiving hydrophones, which are arranged separately from the transmitting transducer. The ultra-short baseline array is used to receive the response sound returned by the transponder. signal, calculating the first position information of the transponder based on the received response sound signal; The short baseline array includes a plurality of the ultra-short baseline arrays. The short baseline array is used to receive the response sound signal returned by the transponder, and calculate the second response sound signal of the transponder based on the received response sound signal. location information; The short baseline array is used to fuse the first position information and the second position information, and calculate the final position information of the transponder; Multiple receiving hydrophones of the same ultra-short baseline array are at different depths in the direction of the target axis; The number of the transponders is multiple, and the plurality of transponders are arranged on the underwater target to be located according to a preset geometric pattern, and each of the transponders is assigned a different exclusive response sound signal; The ultra-short baseline array is used to calculate the first position information of the transponder based on the ultra-short baseline positioning algorithm and the received response sound signal; The short baseline array is used to calculate the second position information of the transponder according to the short baseline positioning algorithm and the received response sound signal. 2. The system according to claim 1, wherein the short baseline array is used to fuse the first position information and the second position information according to the geometric position relationship constraints corresponding to the transponder, Get the final target location information.