Simulating method, system and device for side scan sonar echo with influence of translational error fusion

Abstract

The application discloses a side scan sonar echo simulation method, system and device fusing the influence of translational error, and the method comprises the following steps: according to the motion speed, motion time and three-dimensional space position error information of the side scan sonar deviating from ideal straight line motion, the three-dimensional space coordinates of the side scan sonar when transmitting and receiving signals are solved; the two-way slant range histories between the side scan sonar and each target in space are calculated respectively; the wideband signal transmitted by the transmitting array element is subjected to corresponding time delay processing; the Doppler phase caused by the relative motion between the side scan sonar and the target is calculated in the time domain, and the corresponding Doppler phase is added to the time-delayed signal; the echo signals of all targets are subjected to coherent accumulation in the time domain to obtain a simulation echo signal; and the simulation echo signal is demodulated in the time domain to obtain a baseband echo signal. The side scan sonar echo simulation method can simulate the echo signal of the side scan sonar when the system has translational error with high precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of image processing, in particular to a side scan sonar echo simulation method, system and device fusing the influence of translational error, wherein the side scan sonar echo simulation method can meet the accurate simulation of echo when the side scan sonar has translational error. BACKGROUND

[0002] The ideal side scan sonar towing mode is uniform linear motion, so that the side scan sonar image after operation will not have problems such as stretching, shrinking and target distortion. However, affected by many factors such as ocean wind, wave, surge and towing platform stability, the side scan sonar cannot move in the ideal uniform linear mode during operation, so that the target in the obtained image will be stretched and shrunk due to non-uniform speed, and the target will be distorted due to the left and right swing of the sonar. In fact, the development process of the side scan sonar equipment is very complex, and we do not have actual measurement data to verify various imaging algorithms before the equipment is successfully developed. In this case, the echo data that can simulate the actual situation is particularly important for the verification of various algorithms. The side scan sonar echo simulation in the traditional mode is generally carried out in the uniform linear motion state, and such echo data can only be used for preliminary verification of imaging algorithms. In addition, the ideal situation can only be realized in the laboratory, and cannot better simulate the actual situation of the ocean. SUMMARY

[0003] In view of the above technical problems, the present application provides a side scan sonar echo simulation method, system and device fusing the influence of translational error, wherein the side scan sonar echo simulation method can accurately simulate the side scan sonar echo data under the condition of having translational error, and the side scan sonar echo simulation method comprises the following steps:

[0004] S1. According to the motion speed, motion time and three-dimensional space position error information of the side scan sonar deviating from the ideal linear motion, the three-dimensional space coordinates of the side scan sonar when transmitting and receiving signals are calculated.

[0005] S2. According to the three-dimensional space coordinates of the side scan sonar when transmitting and receiving signals, the two-way slant range histories between the side scan sonar and each target in space are calculated respectively.

[0006] S3. According to the calculated two-way slant range histories, the wideband signal transmitted by the transmitting element is subjected to corresponding time delay processing.

[0007] S4. The Doppler phase caused by the relative target motion of the sonar is calculated in the time domain, and the corresponding Doppler phase is added to the time-delayed signal.

[0008] S5. The echo signals of all targets are coherently accumulated in the time domain to obtain the simulated echo signal.

[0009] S6, demodulating the simulated echo signal in the time domain to obtain a baseband echo signal.

[0010] In step S1, the three-dimensional translation error of the side-scan sonar when sending and receiving signals is calculated based on the side-scan sonar movement speed, movement time, and the three-dimensional translation position error information of the side-scan sonar deviating from the ideal straight line motion: , here It indicates the distance error of the sonar from the ideal position in the track direction. It indicates the distance error of the sonar from the ideal position in the direction perpendicular to the track. Indicates the distance error of the sonar from the ideal position in the depth direction, subscript Indicates The first time sent pulses. Assume that the sonar is at a speed At a distance from the bottom Drag at a height of After that, the ideal positions of the sonar transmitting array elements in the track, vertical track and depth directions are 、 、 , if the three-dimensional translation position error is considered, the transmitting array element is The three-dimensional space coordinates of the moment are ; For the distance from the transmitting array element No. receiving array elements, in The three-dimensional space coordinates of the moment are .

[0011] In step S2, the two-way slant range between the side scan sonar and each target in space is calculated based on the three-dimensional spatial coordinates of the side scan sonar when it sends and receives signals. goals, of which The three-dimensional space coordinates of the target are ,according to The three-dimensional space coordinates of the transmitting element at any moment , calculate the transmit array element and the The distance between the targets for: .according to Moment The three-dimensional coordinates of the receiving array elements , calculate the The receiving array element and the The distance between the targets for: , so we can get the transmitting array element, the The receiving array element and the Two-way slant range of a target for:

[0012] ,

[0013] In step S3, the broadband signal transmitted by the transmitting array element is subjected to corresponding time delay processing according to the calculated two-way slant range history, and its expression is: ,in Represents the broadband signal emitted by the transmitting array element, Indicates the speed at which sonar sound waves travel in water; Indicates the delay of the transmitted signal Later, The signal received by the receiving element.

[0014] In step S4, the Doppler phase of the sonar relative to the target is calculated in the time domain. , and add the corresponding Doppler phase to the delayed signal, the expression is: , among which, here represents the carrier frequency, the relationship is Represents an imaginary unit. Indicates that the sonar system and the first After the Doppler phase effect caused by the relative motion of the first target, The signal received by the receiving element.

[0015] In step S5, the echo signals of all targets are coherently accumulated in the time domain to obtain a simulated echo signal, which is expressed as: ,in, Indicates the total number of targets in the scene. Indicates that for all targets in the scene, The total signal received by the receiving array elements.

[0016] In step S6, the simulated echo signal is demodulated in the time domain to obtain a baseband echo signal: ,in, Indicates the The baseband echo signals of all targets in the entire scene are received by the receiving array elements.

[0017] According to another aspect of the present invention, the present invention further provides a side scan sonar echo simulation system integrating the influence of translation error, which comprises:

[0018] A calculation unit is used to calculate the three-dimensional spatial coordinates of the side-scan sonar when sending and receiving signals based on the side-scan sonar movement speed, movement time, and three-dimensional spatial position error information of the side-scan sonar deviating from the ideal straight line movement;

[0019] A calculation unit is used to calculate the two-way slant range between the side scan sonar and each target in space according to the three-dimensional spatial coordinates when the side scan sonar sends and receives signals;

[0020] A time delay processing unit, configured to perform corresponding time delay processing on the broadband signal transmitted by the transmitting array element according to the calculated two-way slant range history;

[0021] An adding unit is used to calculate the Doppler phase caused by the side scan sonar relative to the target motion in the time domain, and add the corresponding Doppler phase to the delayed signal;

[0022] An accumulation unit, used for coherently accumulating the echo signals of all targets in the time domain to obtain a simulated echo signal;

[0023] The demodulation unit is used to demodulate the simulated echo signal in the time domain to obtain a baseband echo signal.

[0024] According to one embodiment of the present invention, the solving unit solves the three-dimensional translation error of the side scan sonar when sending and receiving signals based on the side scan sonar movement speed, movement time and the three-dimensional translation position error information of the side scan sonar deviating from the ideal straight line motion: ,in It indicates the distance error of the side scan sonar in the deviation from the ideal position in the track direction. It indicates the distance error of the side scan sonar from the ideal position in the direction perpendicular to the track. Indicates the distance error of the side scan sonar from the ideal position in the depth direction. Indicates The first time sent pulses, assuming the side scan sonar is at speed At a distance from the bottom Drag at a height of After that, the ideal positions of the side scan sonar transmitting array elements in the track, vertical track and depth directions are 、 、 , if the three-dimensional translation position error is considered, the transmitting array element is The three-dimensional space coordinates of the moment are , for the distance from the transmitting array element No. receiving array elements, in The three-dimensional space coordinates of the moment are .

[0025] According to another aspect of the present application, the present application further provides a computing device comprising a processor and a memory, wherein computer program instructions are stored in the memory, and the computer program instructions, when executed in the processor, cause the processor to perform the side-scan sonar echo simulation method, wherein the side-scan sonar echo simulation method comprises the following steps:

[0026] S1, according to the side-scan sonar motion speed, motion time and three-dimensional space position error information of the side-scan sonar deviating from the ideal straight line motion, calculating the three-dimensional space coordinates when the side-scan sonar transmits and receives signals;

[0027] S2, according to the three-dimensional space coordinates when the side-scan sonar transmits and receives signals, respectively calculating the two-way slant range histories between the side-scan sonar and each target in space;

[0028] S3, according to the calculated two-way slant range histories, performing corresponding time delay processing on the wideband signals transmitted by the transmitting elements;

[0029] S4, calculating the Doppler phase caused by the relative motion of the side-scan sonar to the target in the time domain, and adding the corresponding Doppler phase to the time-delayed signals;

[0030] S5, coherently accumulating the echo signals of all targets in the time domain to obtain the simulation echo signals;

[0031] S6, demodulating the simulation echo signals in the time domain to obtain the baseband echo signals.

[0032] Compared with the prior art, the present application has at least the following beneficial effects:

[0033] Firstly, the present application can accurately simulate the echo data under the condition of error disturbance, which can assist in solving the problems caused by actual non-ideal motion. On the one hand, we can analyze the echo data under the condition of error disturbance, which can better understand and master the problems caused by non-ideal motion theoretically. On the other hand, we can also study the imaging method under the condition of non-ideal motion based on the echo data, and then use the echo data as the input of the imaging method under the condition of non-ideal motion to verify the function of the entire system;

[0034] Secondly, compared with the ideal mode of traditional uniform straight line motion, the present application considers the influence of three-dimensional translation error on side-scan sonar echo simulation, which can be closer to the working scene of actual sonar equipment, is conducive to analyzing the echo data under the condition of error disturbance, can better understand and master the problems caused by non-ideal motion theoretically, and can also study the imaging method under the condition of non-ideal motion based on the echo data, and then use the echo data as the input of the imaging method under the condition of non-ideal motion to verify the function of the entire system;

[0035] In addition, the echo simulation system established by the present application can also consider the echo simulation under the traditional ideal condition, has a relatively wide application scene and has very important practical significance for the research of the side scan sonar system. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 The flow of the side scan sonar echo simulation method considering the three-dimensional translational error influence of the present application.

[0037] Figure 2 The side scan sonar space model diagram of the present application.

[0038] Figure 3 The echo simulation result under the ideal condition.

[0039] Figure 4 The translational error along the x-axis direction.

[0040] Figure 5 The translational error along the y-axis direction.

[0041] Figure 6 The translational error along the z-axis direction.

[0042] Figure 7 The simulated echo signal under the condition of the x, y and z axis direction translational error.

[0043] Figure 8 The side scan imaging result of the close-range target.

[0044] Figure 9 The side scan imaging result of the long-range target.

[0045] Figure 10 The profile of the close-range target imaging result in the track direction.

[0046] Figure 11 The profile of the long-range target imaging result in the track direction.

[0047] Figure 12 The flow of the side scan sonar echo simulation system of the present application.

[0048] Figure 13 The block diagram of the computing device of the present application.

[0049] In the figure:

[0050] 10, echo simulation system; 11, solution unit; 12, computing unit; 13, time delay processing unit; 14, adding unit; 15, accumulation unit; 16, demodulation unit;

[0051] 20, computing device; 21, processor; 22, memory; 23, input device; 24, output device. DETAILED DESCRIPTION

[0052] Reference is made to the accompanying drawings that form a part of the present description Figures 1 to 11 In a preferred embodiment of the present application, a side-scan sonar echo simulation method considering translational error is provided. The method comprises the following steps: S1, calculating the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals according to the motion speed, motion time, and three-dimensional space position error information of the side-scan sonar deviating from ideal straight-line motion; S2, calculating the two-way slant range history between the side-scan sonar and each target in space according to the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals; S3, performing corresponding time delay processing on the wideband signal transmitted by the transmitting element according to the calculated two-way slant range history; S4, calculating the Doppler phase caused by the relative motion of the side-scan sonar to the target in the time domain, and adding the corresponding Doppler phase to the time-delayed signal; S5, coherently accumulating the echo signals of all targets in the time domain to obtain the simulation echo signal; and S6, demodulating the simulation echo signal in the time domain to obtain the baseband echo signal. Through the above steps, first, the side-scan sonar echo simulation method can accurately simulate the echo data under error disturbance conditions, which can help solve the problems caused by actual non-ideal motion. On the one hand, we can analyze the echo data under error disturbance conditions, which can better understand and master the problems caused by non-ideal motion theoretically. On the other hand, we can also study the imaging method under non-ideal motion conditions based on the echo data, and then use the echo data as the input of the imaging method under non-ideal motion conditions to verify the function of the entire system. Second, compared with the traditional ideal mode of uniform straight-line motion, the side-scan sonar echo simulation method considers the influence of three-dimensional translational error on side-scan sonar echo simulation, which can be closer to the working scene of actual sonar equipment, which is conducive to analyzing the echo data under error disturbance conditions, better understanding and mastering the problems caused by non-ideal motion theoretically, and studying the imaging method under non-ideal motion conditions based on the echo data, and then using the echo data as the input of the imaging method under non-ideal motion conditions to verify the function of the entire system. Third, the echo simulation system established by the side-scan sonar echo simulation method can also consider the echo simulation under the traditional ideal condition, which has a relatively wide application scene and has very important practical significance for the research of side-scan sonar system.

[0053] Specifically, in the step S1, according to the motion speed, motion time, and three-dimensional space translational position error information of the side-scan sonar deviating from ideal straight-line motion, the three-dimensional orthogonal coordinate system as shown in FIG. 1 is established, and the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals are calculated according to the motion speed, motion time, and three-dimensional space translational position error information of the side-scan sonar deviating from ideal straight-line motion. Figure 2 ​x-y-z The three-dimensional translation error when calculating the side scan sonar signal transmission and reception is: , here It indicates the distance error of the side scan sonar in the deviation from the ideal position in the track direction. It indicates the distance error of the side scan sonar from the ideal position in the direction perpendicular to the track. Indicates the distance error of the side scan sonar from the ideal position in the depth direction. Indicates The first time sent pulses. Assume that the side scan sonar is at a speed of At a distance from the bottom The height along x Axis drags, time passes After that, the ideal positions of the side scan sonar transmitting array elements in the track, vertical track and depth directions are 、 、 , if the three-dimensional translation position error is considered, the transmitting array element is The three-dimensional space coordinates of the moment are ; For the distance from the transmitting array element No. receiving array elements, in The three-dimensional space coordinates of the moment are .

[0054] In step S2, the two-way slant range between the side scan sonar and each target in space is calculated based on the three-dimensional spatial coordinates of the side scan sonar when it sends and receives signals. goals, of which The three-dimensional space coordinates of the target are ,according to The three-dimensional space coordinates of the transmitting element at any moment ,calculate Figure 2 The transmitting element and the The distance between the targets for: .according to Moment The three-dimensional coordinates of the receiving array elements ,calculate Figure 2 Middle The receiving array element and the The distance between the targets for: , so we can get the transmitting array element, the The receiving array element and the Two-way slant range of a target for: .

[0055] In the step S3, according to the calculated two-way slant range history, the wideband signal transmitted by the transmitting element is processed with corresponding time delay, the expression is: wherein represents the wideband signal transmitted by the transmitting element, represents the speed of the sonar sound wave propagating in water; represents the delay of the transmitting signal and the signal received by the first receiving element.

[0056] In the step S4, the Doppler phase caused by the relative target motion of the side scan sonar is calculated in time domain , and the corresponding Doppler phase is added to the time-delayed signal, the expression is: wherein, here represents the carrier frequency, the relationship is represents the imaginary unit. represents the signal received by the first receiving element after the Doppler phase caused by the relative motion between the side scan sonar system and the first target is added to the delayed transmitting signal.

[0057] In the step S5, the echo signals of all targets are coherently accumulated in time domain to obtain the simulated echo signal, the expression is: wherein, represents the total number of targets existing in the scene. represents the total signal received by the first receiving element for all targets in the scene.

[0058] In the step S6, the simulated echo signal is demodulated in time domain to obtain the baseband echo signal: wherein, represents the baseband echo signal of all targets in the entire scene received by the first receiving element.

[0059] We assume that the beam angle of the receiving array is 0.00559 radians, and the bandwidth of the transmitted linear frequency modulation signal is 30 kHz. We assume that there are 2 ideal point targets in space, and the coordinates of the ideal point target at a close distance on the x-axis, y-axis, and z-axis are 23 m, 24 m, and 0 m respectively; the coordinates of the ideal point target at a long distance on the x-axis, y-axis, and z-axis are 23 m, 85.42 m, and 0 m respectively. When the side scan sonar moves along the x-axis, there is no motion error on the x-axis, y-axis, and z-axis, and the simulated echo signal is as follows: Figure 3As shown, it is not difficult to find that the side scan sonar echo simulation method of the present invention can also simulate the echo signal when there is no translation error; assuming that there are Figure 4 、 Figure 5 、 Figure 6 The translation error shown in the figure is as follows: Figure 7 As shown. In the signal processing process, consider Figure 4 、 Figure 5 、 Figure 6 The translation error shown is Figure 7 The echo signal with motion error is imaged using dynamic focusing beamforming algorithm. The target at close range is as follows: Figure 8 As shown, the target at a long distance is Figure 9 As shown in Figure 2, it is not difficult to find that the imaging result is better after considering the translation error. The profile of the imaging result in the track direction is extracted, and the profile at close distance is as follows: Figure 10 As shown, the cross section at a long distance is as follows Figure 11 As shown in the cross-sectional diagram, the resolutions for near- and far-range imaging targets are calculated to be 0.16m and 0.49m, respectively. The theoretical resolutions for near- and far-range imaging, calculated based on the receiving array beam angle, are 0.15m and 0.48m, respectively. Comparing the theoretical resolutions with the actual resolutions calculated from the cross-sectional diagrams reveals that the processed results are essentially consistent with the theoretical results, within the error range, further validating the accuracy of the side-scan sonar echo simulation method of the present invention.

[0060] Reference Attachment Figure 12 The present invention also provides a side-scan sonar echo simulation system 10 that integrates the influence of translational error, which is used to simulate the echo of the side-scan sonar, wherein the side-scan sonar echo simulation system 10 includes a solution unit 11, a calculation unit 12, a time delay processing unit 13, an addition unit 14, an accumulation unit 15 and a demodulation unit 16. The solution unit 11, the calculation unit 12, the time delay processing unit 13, the addition unit 14, the accumulation unit 15 and the demodulation unit 16 cooperate with each other to realize the echo simulation of the side-scan sonar.

[0061] Specifically, the solving unit 11 is used to solve the three-dimensional spatial coordinates of the side scan sonar when sending and receiving signals according to the side scan sonar movement speed, movement time and the three-dimensional spatial position error information of the side scan sonar deviating from the ideal straight line motion, wherein the solving unit 11 is used to solve the three-dimensional spatial coordinates of the side scan sonar when sending and receiving signals according to the side scan sonar movement speed, movement time and the three-dimensional spatial translation position error information of the side scan sonar deviating from the ideal straight line motion, Figure 2 The three-dimensional rectangular coordinate system shown x-y-z In the example, the solving unit 11 solves the three-dimensional translation error when the side scan sonar sends and receives signals as ,in represents the distance error of the side scan sonar in the track direction deviating from the ideal position, represents the distance error of the side scan sonar in the vertical track direction deviating from the ideal position, represents the distance error of the side scan sonar in the depth direction deviating from the ideal position, subscript represents the th pulse transmitted at time , assuming that the side scan sonar is towed along the axis at a height of from the water bottom, after a time x , the ideal positions of the transmitting array elements in the track, vertical track and depth directions are , , , respectively, if considering the three-dimensional spatial translation position error, the three-dimensional spatial coordinates of the transmitting array element at time are ; for the th receiving array element spaced apart from the transmitting array element by , the three-dimensional spatial coordinates at time are .

[0062] The computing unit 12 is configured to calculate the two-way slant range history between the side scan sonar and each target in space according to the three-dimensional spatial coordinates of the side scan sonar when transmitting and receiving signals, wherein it is assumed that there are targets in the horizontal plane, wherein the three-dimensional spatial coordinates of the th target are , according to the three-dimensional spatial coordinates of the transmitting array element at time , , the distance between the transmitting array element and the Figure 2 th target in is calculated as: , , according to the three-dimensional spatial coordinates of the th receiving array element at time , , the distance between the Figure 2 th receiving array element and the th target in is calculated as: , , thus the two-way slant range between the transmitting array element, the th receiving array element and the th target is: . .

[0063] The time delay processing unit 13 is configured to perform time delay processing on the wideband signal transmitted by the transmitting element according to the calculated two-way slant range history, and the expression is as follows: , wherein represents the wideband signal transmitted by the transmitting element, represents the speed of propagation of the sonar sound wave in water; represents the delay of the transmitting signal , and the signal received by the i th receiving element.

[0064] The adding unit 14 is configured to calculate the Doppler phase caused by the relative motion of the side-scan sonar to the target in the time domain, and add the corresponding Doppler phase to the time-delayed signal, wherein the Doppler phase caused by the relative motion of the side-scan sonar to the target in the time domain is , and the corresponding Doppler phase is added to the time-delayed signal, and the expression is as follows: , wherein here represents the carrier frequency, and the relationship is represents the imaginary unit. represents the signal received by the i th receiving element after the Doppler phase caused by the relative motion of the side-scan sonar to the i th target is added to the delayed transmitting signal.

[0065] The adding unit 15 is configured to coherently add the echo signals of all targets in the time domain to obtain a simulated echo signal, and the expression is as follows: , wherein represents the total number of targets existing in the scene. represents the total signal received by the i th receiving element for all targets in the scene.

[0066] The demodulation unit 16 is configured to demodulate the simulated echo signal in the time domain to obtain a baseband echo signal , wherein represents the baseband echo signal of all targets in the entire scene received by the i th receiving element. The accompanying drawings are referred to in the description of the embodiments.

[0067] Figure 13 ​​​​​According to another aspect of the present application, the present application further provides a computing device 20, wherein the computing device 20 comprises a processor 21 and a memory 22, and computer program instructions are stored in the memory 22, and the computer program instructions make the processor 21 execute the side-scan sonar echo simulation method when running in the processor 21, wherein the side-scan sonar echo simulation method comprises the following steps: S1, calculating the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals according to the side-scan sonar motion speed, motion time and three-dimensional space position error information of the side-scan sonar deviating from the ideal straight line motion; S2, calculating the two-way slant range history between the side-scan sonar and each target in space respectively according to the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals; S3, performing corresponding time delay processing on the wideband signal transmitted by the transmitting element according to the calculated two-way slant range history; S4, calculating the Doppler phase caused by the relative motion of the side-scan sonar to the target in the time domain, and adding the corresponding Doppler phase to the time-delayed signal; S5, coherently accumulating the echo signals of all targets in the time domain to obtain the simulation echo signal; and S6, demodulating the simulation echo signal in the time domain to obtain the baseband echo signal.

[0068] Thus, first, the computing device 20 of the present application can accurately simulate the echo data under the condition of error disturbance, which can assist in solving the problems caused by actual non-ideal motion. On the one hand, we can analyze the echo data under the condition of error disturbance, which can better understand and master the problems caused by non-ideal motion theoretically. On the other hand, we can also study the imaging method under the condition of non-ideal motion based on the echo data, and then use the echo data as the input of the imaging method under the condition of non-ideal motion to verify the function of the entire system. Second, compared with the traditional ideal mode of uniform straight line motion, the computing device 20 of the present application considers the influence of three-dimensional translation error on side-scan sonar echo simulation, which can be closer to the working scene of actual sonar equipment, is conducive to analyzing the echo data under the condition of error disturbance, can better understand and master the problems caused by non-ideal motion theoretically, and can also study the imaging method under the condition of non-ideal motion based on the echo data, and then use the echo data as the input of the imaging method under the condition of non-ideal motion to verify the function of the entire system. Third, the echo simulation system established by the computing device 20 of the present application can also consider the echo simulation under the traditional ideal condition, has a relatively wide application scene and has very important practical significance for the research of side-scan sonar system.

[0069] In an embodiment of the computing device 20 of the present application, the memory 22 can include one or more computer program products, which can include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory, for example, can include random access memory (RAM), cache memory, and / or the like. The non-volatile memory, for example, can include read-only memory (ROM), hard disk drives, solid-state drives, and / or the like. The computer-readable storage media can store one or more computer program instructions, which can be executed by the processor 21 to implement the functions of the side-scan sonar echo simulation method of the present application described above.

[0070] In an embodiment of the computing device 20 of the present application, the processor 21 can be a central processing unit (CPU) or other form of processing unit having data processing and / or instruction execution capabilities, which can execute the program instructions stored on the computer-readable storage media to implement the functions of the side-scan sonar echo simulation method of the present application described above.

[0071] In an embodiment of the computing device 20 of the present application, the computing device 20 can further include an input device 23 and an output device 24. The input device 23 can be, but is not limited to, a keyboard, a mouse, and the like. The output device 24 can be, but is not limited to, a display, a speaker, a printer, and the like. The input device 23 and the output device 24 can be connected to the processor 21 through a bus system.

[0072] It should be understood by those skilled in the art that the above description and the embodiments of the present application shown in the drawings are only examples and do not limit the present application. The object of the present application has been fully and effectively achieved. The functional and structural principles of the present application have been demonstrated and described in the embodiments, and the embodiments of the present application can be modified or changed in any way without departing from the principles.

Claims

1. A method of side-scan sonar echo simulation fusing the influence of translation error, used for echo simulation of side-scan sonar, characterized in that, The side-scan sonar echo simulation method comprises the following steps: S1, calculating the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals according to the motion speed, motion time and three-dimensional space position error information of the side-scan sonar deviating from ideal straight-line motion; S2, calculating the two-way slant range history between the side-scan sonar and each target in space respectively according to the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals; S3, performing corresponding time delay processing on the wideband signal transmitted by the transmitting array element according to the calculated two-way slant range history; S4, calculating the Doppler phase caused by the relative motion of the side-scan sonar to the target in the time domain, and adding the corresponding Doppler phase to the time-delayed signal; S5, coherently accumulating the echo signals of all targets in the time domain to obtain a simulation echo signal; S6, demodulating the simulation echo signal in the time domain to obtain a baseband echo signal; In step S1, the three-dimensional translation error of the side-scan sonar when sending and receiving signals is calculated based on the side-scan sonar movement speed, movement time, and the three-dimensional translation position error information of the side-scan sonar deviating from the ideal straight line motion: ,in It indicates the distance error of the side scan sonar in the deviation from the ideal position in the track direction. It indicates the distance error of the side scan sonar from the ideal position in the direction perpendicular to the track. Indicates the distance error of the side scan sonar from the ideal position in the depth direction. Indicates The first time sent pulses, assuming the side scan sonar is at speed At a distance from the bottom Drag at a height of After that, the ideal positions of the side scan sonar transmitting array elements in the track, vertical track and depth directions are 、 、 , if the three-dimensional translation position error is considered, the transmitting array element is The three-dimensional space coordinates of the moment are , for the distance from the transmitting array element No. receiving array elements, in The three-dimensional space coordinates of the moment are ; In step S2, the two-way slant range between the side scan sonar and each target in space is calculated based on the three-dimensional spatial coordinates of the side scan sonar when it sends and receives signals. Assuming that there is goals, of which The three-dimensional space coordinates of the target are ,according to The three-dimensional space coordinates of the transmitting element at any moment , calculate the transmit array element and the The distance between the targets for: ,according to Moment The three-dimensional coordinates of the receiving array elements , calculate the The receiving array element and the The distance between the targets for: , get the transmitting array element, the The receiving array element and the Two-way slant range of a target for: .

2. The side-scan sonar return simulation method that fuses the effects of translation errors according to claim 1, wherein, In said step S3, the wide-band signal emitted by the transmitting element is subjected to a corresponding time delay processing, expressed by: wherein represents the wide-band signal emitted by the transmitting element, represents the speed of propagation of the side-scan sonar acoustic wave in water, represents the delay of the transmitted signal, and wherein the signal received by the nth receiving element is given by: ​ 3. The side-scan sonar return simulation method that fuses the effects of translation errors according to claim 2, wherein, In the step S4, the Doppler phase caused by the relative target motion is calculated in time domain for the side scan sonar and added to the time-delayed signal, whose expression is: where here denotes the carrier frequency, the relationship is denotes the imaginary unit, denotes the signal received by the first receiving element after the Doppler phase influence caused by the relative motion between the side scan sonar system and the first target is added to the delayed transmitted signal. ​​ 4. The side-scan sonar return simulation method that fuses the effects of translation errors according to claim 3, wherein, In the step S5, the echo signals of all targets are coherently accumulated in time domain to obtain a simulation echo signal, whose expression is: wherein represents the total number of targets existing in the scene, represents the total signal received by the th receiving array element for all targets in the scene.

5. The side-scan sonar return simulation method that fuses the effects of translation errors according to claim 4, wherein, In the step S6, the echo signals of all targets are demodulated in time domain to obtain baseband echo signals: wherein represents the baseband echo signals of all targets in the whole scene received by the th receiving element.

6. A side scan sonar echo simulation system that fuses the effects of translational errors, characterized in that, comprise: a calculation unit configured to calculate the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals according to the motion speed, motion time and three-dimensional space position error information of the side-scan sonar deviating from ideal straight-line motion; a calculation unit configured to calculate the two-way slant range history between the side-scan sonar and each target in space respectively according to the three-dimensional space coordinates of the side-scan sonar when transmitting and receiving signals; a time delay processing unit configured to perform corresponding time delay processing on the wideband signal transmitted by the transmitting array element according to the calculated two-way slant range history; an adding unit configured to calculate the Doppler phase caused by the relative motion of the side-scan sonar to the target in the time domain, and add the corresponding Doppler phase to the time-delayed signal; an accumulation unit configured to coherently accumulate the echo signals of all targets in the time domain to obtain a simulation echo signal; a demodulation unit configured to demodulate the simulation echo signal in the time domain to obtain a baseband echo signal; The solving unit solves the three-dimensional translation error of the side scan sonar when sending and receiving signals based on the side scan sonar movement speed, movement time and the three-dimensional translation position error information of the side scan sonar deviating from the ideal straight line movement: ,in It indicates the distance error of the side scan sonar in the deviation from the ideal position in the track direction. It indicates the distance error of the side scan sonar from the ideal position in the direction perpendicular to the track. Indicates the distance error of the side scan sonar from the ideal position in the depth direction. Indicates The first time sent pulses, assuming the side scan sonar is at speed At a distance from the bottom Drag at a height of After that, the ideal positions of the side scan sonar transmitting array elements in the track, vertical track and depth directions are 、 、 , if the three-dimensional translation position error is considered, the transmitting array element is The three-dimensional space coordinates of the moment are , for the distance from the transmitting array element No. receiving array elements, in The three-dimensional space coordinates of the moment are ; The calculation unit calculates the two-way slant range between the side scan sonar and each target in space according to the three-dimensional spatial coordinates of the side scan sonar when sending and receiving signals, assuming that there is a goals, of which The three-dimensional space coordinates of the target are ,according to The three-dimensional space coordinates of the transmitting element at any moment , calculate the transmit array element and the The distance between the targets for: ,according to Moment The three-dimensional coordinates of the receiving array elements , calculate the The receiving array element and the The distance between the targets for: , get the transmitting array element, the The receiving array element and the Two-way slant range of a target for: .

7. A computing device, characterized by comprise a processor and a memory, wherein computer program instructions are stored in the memory, and the computer program instructions run in the processor to make the processor execute the side-scan sonar echo simulation method according to any one of claims 1 to 5.

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