Combined measurement method and system of polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection

Abstract

The present invention belongs to the field of polar acoustic technology, and specifically relates to a joint measurement method for polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection and a measurement system thereof. Step 1: deploying a transceiver system; Step 2: setting parameters for the transceiver system deployed in step 1; Step 3: based on the transceiver system set in step 2, collecting its signal and calculating the propagation time; Step 4: calculating the sea ice thickness and sound velocity in ice based on the propagation time calculated in step 3. The present invention is aimed at the polar environment and the problem that the existing sea ice thickness measurement method has limited applicability and poor practicality in the polar environment.

Description

Technical Field

[0001] The present invention belongs to the field of polar acoustic technology, and in particular relates to a joint measurement method and a measurement system for polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection. Background Art

[0002] Polar sea ice thickness measurement technology based on ultrasonic echo refers to a technical method that uses ultrasonic echoes at the ice-water interface to measure sea ice thickness and determine the sound velocity in ice in a polar environment. The sound velocity and ice thickness of polar sea ice are the two most basic parameters required to describe the acoustic characteristics of sea ice, and there is a close relationship between them. When measuring the sound velocity in sea ice, it is necessary to measure the sea ice thickness in advance; conversely, when measuring the sea ice thickness using the ultrasonic echo method, it is necessary to estimate the sound velocity in ice in advance. These two parameters are the prerequisites for the study of acoustic characteristics in ice. The sound velocity in sea ice can lay a theoretical foundation for the research of engineering applications such as cross-ice communications. The continuous observation of sea ice thickness can also serve as a window for monitoring polar temperature fluctuations.

[0003] Traditional methods for measuring sea ice thickness can be roughly divided into the following three types. (1) Directly measuring the thickness of the ice sample to be measured after destroying the ice layer. However, this type of method has disadvantages such as high risk and poor operability in polar environments. (2) Using the propagation time of the ice-water interface echo to measure the thickness of the ice sample to be measured on the premise of estimating the sound velocity in the ice. However, sea ice in polar environments is mostly multi-year ice, and the sound velocity in the ice is difficult to estimate, resulting in a large difference between the measured ice thickness and the actual ice thickness. (3) Using the longitudinal temperature change inside the sea ice to measure the thickness of the ice sample to be measured using a temperature chain, but the existence of a subglacial melt pond under the sea ice may cause the ice temperature chain to have a large error in determining the position of the ice-water interface during the measurement process. Traditional sea ice sound velocity measurement requires destroying the ice layer, taking out the ice core and grinding both sides of the ice core to measure the thickness of the ice core, and further measuring the sound velocity in the ice. However, in polar environments, this type of method has great safety risks and is not very operational.

[0004] In summary, the existing sea ice thickness measurement and ice sound speed measurement methods are difficult to meet the requirements of sea ice thickness measurement in polar environments in terms of practicality and applicability. The present invention aims at the polar environment and the problem that the existing sea ice thickness measurement methods are limited in applicability and not very practical in polar environments. Based on the propagation time of the ice-water interface echo in sea ice, a joint characterization method for sea ice thickness and ice sound speed is proposed. The sea ice thickness and ice sound speed can be flexibly measured by quickly deploying a combined transmitting and receiving system on the ice surface. Summary of the invention

[0005] The present invention provides a joint measurement method for polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection, aiming at the polar environment and the problem that the existing sea ice thickness measurement method has limited applicability and poor practicality in the polar environment.

[0006] The present invention provides a joint measurement system of polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection, which is used to implement a joint measurement method of polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection.

[0007] The present invention is achieved through the following technical solutions:

[0008] A combined measurement method for polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection, the combined measurement method comprising the following steps:

[0009] Step 1: Deployment of the combined transceiver system;

[0010] Step 2: Setting parameters for the combined transceiver system deployed in step 1;

[0011] Step 3: Based on the combined transceiver system set up in step 2, collect its signal and calculate the propagation time;

[0012] Step 4: Calculate the sea ice thickness and the sound speed in the ice based on the propagation time calculated in step 3.

[0013] Furthermore, the step 1 is specifically to place a transmitting probe on a flat place on the sea ice surface, and to place a number of receiving probes at equal intervals r on a straight line on one side thereof, the probes are coupled to the sea ice surface by water, and grooves are dug between the transmitting and receiving probes to destroy the direct wave effect.

[0014] Furthermore, the step 2 is specifically to set the parameters related to the transmission signal and the receiving channel to achieve the best reception effect of the ice-water interface echo after passing through different propagation paths, wherein the transmission signal setting includes the transmission signal transmission waveform, the transmission signal frequency f, and the transmission signal pulse width Δτ;

[0015] The receiving channel settings include the sampling frequency fs, the number of sampling points n, the dynamic range D, and the signal bit width B of the receiving channel.

[0016] Furthermore, the step 3 specifically includes the following steps:

[0017] Step 3.1: echo signal filtering processing;

[0018] Step 3.2: Use the filtered signal in step 3.1 to perform cross-correlation calculation;

[0019] Step 3.3: Use the result of step 3.2 to calculate the propagation time.

[0020] Furthermore, the step 3.1 is specifically that, after synchronous transmission and reception, the received signals y1, y2, and y3 of each receiving channel are band-pass filtered at 1 / 2 octave of the center frequency f of the transmitting signal to eliminate noise interference on the echo, that is, the filtering frequency band is Obtain filtered signals y1', y2', y3';

[0021] Specifically, the step 3.2 is to perform cross-correlation calculation on the filtered signals y1', y2', y3' and the transmitted signal, and extract the cross-correlation result envelope peaks loc1, loc2, loc3 using Hilbert transform;

[0022] Specifically, step 3.3 is to combine the cross-correlation envelope peaks loc1, loc2, loc3 and the received signal sampling frequency fs to obtain the first echo propagation time t of each echo signal. i =loc i / fs.

[0023] Furthermore, the step 4 specifically includes the following steps:

[0024] Step 4.1: Construct the acoustic signal arrival time equation using the ice-water interface echo received by the receiving probe at different distances from the transmitting probe;

[0025] Step 4.2: The purpose of joint measurement of sea ice thickness and sound speed in ice is achieved by solving the ice-water interface echo arrival time equations.

[0026] Furthermore, the step 4.1 is specifically as follows: assuming that the thickness of the sea ice is d and the speed of sound in the ice is c, the equation for the first arrival of the interface echo on different propagation paths can be obtained:

[0027]

[0028] Among them, t1 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 1, t2 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 2, t3 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 3, and r is the distance between ultrasonic probes.

[0029] Furthermore, the step 4.2 is specifically as follows: in the interface echo arrival equation, the corresponding sea ice thickness d can be obtained by linking each of the two equations: i and the speed of sound in ice c i

[0030]

[0031] Combining the three groups d1-c1, d2-c2, and d3-c3, we can calculate the average thickness of sea ice d and the average sound speed in ice c.

[0032]

[0033] A combined measurement system for polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection, the combined measurement system uses the combined measurement method for polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection as described above, the combined measurement system comprises:

[0034] A parameter setting module records the spacing data of the deployed transceiver system and sets parameters for the deployed transceiver system;

[0035] Acquisition module: collects signals from the transceiver system;

[0036] The calculation module is used to calculate the propagation time and the thickness of sea ice and the speed of sound in ice.

[0037] A computer-readable storage medium stores a computer program, and the computer program implements the above method when executed by a processor.

[0038] The beneficial effects of the present invention are:

[0039] The present invention is based on the ice-water interface echo and can measure the sea ice thickness and the sound speed in the ice on the sea ice surface without destroying the sea ice, thereby improving the operability and safety of the measurement.

[0040] The present invention is based on ice-water interface echoes received by different receiving probes, and uses a combined transmitting and receiving system to synchronously measure the sea ice thickness and the sound speed in the ice, thereby avoiding the error in sea ice thickness measurement caused by the advance estimation of the sound speed in the traditional sea ice thickness measurement method.

[0041] The present invention calculates the sea ice thickness by using the ice-water interface echo on the lower surface of the sea ice, which can correspondingly avoid the influence of the sub-ice melt pond on the error in measuring the sea ice thickness due to the longitudinal temperature change of the sea ice.

[0042] During experimental measurement, the direct wave path is destroyed between the transmitting and receiving probes, direct wave interference is reduced, and the accuracy of ice thickness and sound velocity measurement is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a flow chart of the method of the present invention.

[0044] Figure 2 It is a schematic diagram of the combined transmitting and receiving system device of the present invention.

[0045] Figure 3 It is a schematic diagram of the placement of ultrasonic transducers in an embodiment of the present invention.

[0046] Figure 4It is a schematic diagram of the transmitting and receiving time domain waveforms in an embodiment of the present invention.

[0047] Figure 5 It is a schematic diagram of the cross-correlation results between the transmitting waveform and different receiving waveforms in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0049] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0050] It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, the singular forms "a", "an" and "the" are intended to include plural forms unless the context clearly indicates otherwise.

[0051] The following is attached to this application specification Figure 1-5 , the technical solutions in the embodiments of the present application are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0052] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0053] Implementation Method 1

[0054] This embodiment provides a joint measurement method for polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection, the joint measurement method comprising the following steps:

[0055] Step 1: Deployment of the combined transceiver system;

[0056] Step 2: Setting parameters for the combined transceiver system deployed in step 1;

[0057] Step 3: Based on the combined transceiver system set up in step 2, collect its signal and calculate the propagation time;

[0058] Step 4: Calculate the sea ice thickness and the sound speed in the ice based on the propagation time calculated in step 3.

[0059] The present invention arranges a transmitting probe and a plurality of receiving probes which are equally spaced and in a straight line with the transmitting probe on the surface of the ice layer, and realizes the joint measurement of the sea ice thickness and the sound speed in the ice by receiving echoes excited by the transmitting probe and reflected by the ice-water interface once by different receiving probes.

[0060] Furthermore, the step 1 is specifically to place a transmitting probe on a flat place on the sea ice surface, and to place a number of receiving probes at equal intervals r on a straight line on one side thereof, the probes are coupled to the sea ice surface by water, and grooves are dug between the transmitting and receiving probes to destroy the direct wave effect.

[0061] Furthermore, the step 2 is specifically to set the parameters related to the transmission signal and the receiving channel to achieve the best reception effect of the ice-water interface echo after passing through different propagation paths, wherein the transmission signal setting includes the transmission signal transmission waveform, the transmission signal frequency f, and the transmission signal pulse width Δτ;

[0062] The receiving channel settings include the sampling frequency fs (fs>2·f) of the receiving channel, the number of sampling points n (the number of sampling points must be sufficient to include the first arrival of each echo signal), the dynamic range D, and the signal bit width B.

[0063] Furthermore, the step 3 specifically includes the following steps:

[0064] Step 3.1: echo signal filtering processing;

[0065] Step 3.2: Use the filtered signal in step 3.1 to perform cross-correlation calculation;

[0066] Step 3.3: Use the result of step 3.2 to calculate the propagation time.

[0067] Furthermore, the step 3.1 is specifically that, after synchronous transmission and reception, the received signals y1, y2, and y3 of each receiving channel are band-pass filtered at 1 / 2 octave of the center frequency f of the transmitting signal to eliminate noise interference on the echo, that is, the filtering frequency band is Obtain filtered signals y1', y2', y3';

[0068] Specifically, the step 3.2 is to perform cross-correlation calculation on the filtered signals y1', y2', y3' and the transmitted signal, and extract the cross-correlation result envelope peaks loc1, loc2, loc3 using Hilbert transform;

[0069] Specifically, step 3.3 is to combine the cross-correlation envelope peaks loc1, loc2, loc3 and the received signal sampling frequency fs to obtain the first echo propagation time t of each echo signal. i =loc i / fs.

[0070] Furthermore, the step 4 specifically includes the following steps:

[0071] Step 4.1: Construct the acoustic signal arrival time equation using the ice-water interface echo received by the receiving probe at different distances from the transmitting probe;

[0072] Step 4.2: The purpose of joint measurement of sea ice thickness and sound speed in ice is achieved by solving the ice-water interface echo arrival time equations.

[0073] Furthermore, the step 4.1 is specifically as follows: assuming that the thickness of the sea ice is d and the speed of sound in the ice is c, the equation for the first arrival of the interface echo on different propagation paths can be obtained:

[0074]

[0075] Among them, t1 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 1, t2 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 2, t3 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 3, and r is the distance between ultrasonic probes.

[0076] Furthermore, the step 4.2 is specifically as follows: in the interface echo arrival equation, the corresponding sea ice thickness d can be obtained by linking each of the two equations: i and the speed of sound in ice c i

[0077]

[0078] Combining the three groups d1-c1, d2-c2, and d3-c3, we can calculate the average thickness of sea ice d and the average sound speed in ice c.

[0079]

[0080] Specifically, the above ice thickness and sound velocity measurement method was used to test an aluminum sample with a length, width and height of 0.24m. Figure 3, the transceiver probes are placed on the upper surface of the aluminum sample at the same interval r = 0.03m. At this time, the thickness of the aluminum sample to be measured is d = 0.24m. The sound velocity in the aluminum sample is measured by the direct wave method to be 6240m / s. The transmission signal is set to a frequency of 2MHz~3MHz and a pulse width of Δτ = 1×10 -5 s linear frequency modulation signal; set the sampling interval in the receiving channel to fs = 1.25 × 10 8 , the sampling signal length is 1×10 5 The transmitting signal and the receiving probe R1, R2, R3 signals are: Figure 4 The signals of the receiving probes R1, R2, and R3 are cross-correlated with the transmitting signals, and the cross-correlation results are shown in Figure 5 As shown. The cross-correlation peaks are extracted to calculate the propagation time. The propagation time of the interface echo signals received by the receiving probes R1, R2, and R3 are t1=7.6568×10 -5 s, t2=7.6976×10 - 5 s, t1=7.7816×10 -5 Furthermore, the thickness of the aluminum sample measured by this method is 0.2363m, the speed of sound in aluminum is 6187m / s, the error between the thickness measurement and the actual value is 1.54%, and the error between the speed of sound in aluminum measured by this method and the speed of sound in aluminum measured by the direct wave method is 0.85%.

[0081] Implementation Method 2

[0082] This embodiment provides a joint measurement system of polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection. This embodiment uses the joint measurement method of polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection as in embodiment 1. The joint measurement system includes:

[0083] A parameter setting module records the spacing data of the deployed transceiver system and sets parameters for the deployed transceiver system;

[0084] Acquisition module: collects signals from the transceiver system;

[0085] The calculation module is used to calculate the propagation time and the thickness of sea ice and the speed of sound in ice.

[0086] Implementation Method 3

[0087] An embodiment of the present invention provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the memory is used to store software programs and modules, and the processor executes various functional applications and data processing by running the software programs and modules stored in the memory. The memory and the processor are connected via a bus. Specifically, the processor implements any step in the first embodiment above by running the computer program stored in the memory.

[0088] It should be understood that in the embodiments of the present invention, the processor referred to may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0089] The memory may include a read-only memory, a flash memory, and a random access memory, and provides instructions and data to the processor. A part or all of the memory may also include a nonvolatile random access memory.

[0090] As can be seen from the above, the electronic device provided by the embodiment of the present invention can implement the joint measurement method as described in Implementation Example 1 by running a computer program, and obtain a new measurement method, in which a transmitting probe and several receiving probes that are equally spaced and in a straight line with the transmitting probe are arranged on the surface of the ice layer, and the echoes excited by the transmitting probe and reflected by the ice-water interface are received by different receiving probes to realize the joint measurement of sea ice thickness and sound speed in ice. The present invention is intended to address the problem of limited applicability and poor practicality of existing sea ice thickness measurement methods in polar environments, and realize the joint measurement of sea ice thickness and sound speed in ice based on the propagation time of the echo at the ice-water interface in sea ice.

[0091] It should be understood that if the above-mentioned integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The above-mentioned computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the above-mentioned computer program includes computer program code, and the above-mentioned computer program code can be in source code form, object code form, executable file or some intermediate form. The above-mentioned computer-readable medium may include: any entity or device capable of carrying the above-mentioned computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the above-mentioned computer-readable storage medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction.

[0092] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0093] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the above-mentioned device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0094] It should be noted that the methods and detailed examples provided in the above embodiments can be combined with the devices and equipment provided in the embodiments, and references can be made to each other, and no further details will be given.

[0095] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0096] In the embodiments provided by the present invention, it should be understood that the disclosed apparatus / terminal equipment and method can be implemented in other ways. For example, the apparatus / equipment embodiments described above are only illustrative, for example, the division of the above modules or units is only a logical function division, and in actual implementation, other division methods can be used, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0097] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention.

Claims

1. A joint measurement method for polar sea ice thickness and sound velocity in ice based on ultrasonic interface echo detection, characterized in that: The joint measurement method comprises the following steps: Step 1: Deployment of the combined transceiver system; Step 2: Setting parameters for the combined transceiver system deployed in step 1; Step 3: Based on the combined transmitting and receiving system set up in step 2, collect its signal and calculate the propagation time, wherein the propagation time is the first echo propagation time of each echo signal; Step 4: Calculate the sea ice thickness and the sound speed in the ice based on the propagation time calculated in step 3; Specifically, step 1 comprises placing a transmitting probe on a flat surface of the sea ice, and placing a plurality of receiving probes at equal intervals r on a straight line on one side of the transmitting probe, coupling the probes to the sea ice surface with water, and digging grooves between the transmitting and receiving probes to destroy the direct wave effect; The step 4 specifically includes the following steps: Step 4.1: Construct the acoustic signal arrival time equation using the ice-water interface echo received by the receiving probe at different distances from the transmitting probe; Step 4.2: The purpose of joint measurement of sea ice thickness and sound speed in ice is achieved by solving the ice-water interface echo arrival time equations; Specifically, step 4.1 is as follows: assuming that the thickness of the sea ice is d and the speed of sound in the ice is c, the equation for the first arrival of the interface echo on different propagation paths can be obtained: Among them, t1 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 1, t2 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 2, t3 is the propagation time of the echo reflected from the ice-water interface by the transmitted signal received by receiving channel 3, and r is the distance between ultrasonic probes.

2. The joint measurement method according to claim 1, characterized in that: The step 2 specifically includes setting the parameters related to the transmission signal and the receiving channel to achieve the best reception effect of the ice-water interface echo after passing through different propagation paths, wherein the transmission signal setting includes the transmission signal waveform, the transmission signal frequency f, and the transmission signal pulse width Δτ; The receiving channel settings include the sampling frequency fs, the number of sampling points n, the dynamic range D, and the signal bit width B of the receiving channel.

3. The joint measurement method according to claim 1, characterized in that: The step 3 specifically includes the following steps: Step 3.1: echo signal filtering processing; Step 3.2: Use the filtered signal in step 3.1 to perform cross-correlation calculation; Step 3.3: Use the result of step 3.2 to calculate the propagation time.

4. The joint measurement method according to claim 3, characterized in that: Specifically, step 3.1 is as follows: after synchronous transmission and reception, the received signals y1, y2, and y3 of each receiving channel are band-pass filtered at 1 / 2 octave of the center frequency f of the transmitting signal to eliminate noise interference on the echo, that is, the filtering frequency band is Obtain filtered signals y1', y2', y3'; Specifically, the step 3.2 is to perform cross-correlation calculation on the filtered signals y1', y2', y3' and the transmitted signal, and extract the cross-correlation result envelope peaks loc1, loc2, loc3 using Hilbert transform; Specifically, step 3.3 is to combine the cross-correlation envelope peaks loc1, loc2, loc3 and the received signal sampling frequency fs to obtain the first echo propagation time t of each echo signal. i =loc i / fs.

5. The joint measurement method according to claim 1, characterized in that: Specifically, step 4.2 is as follows: In the interface echo arrival equation, the corresponding sea ice thickness d can be obtained by linking the two equations: i and the speed of sound in ice c i Combining the three groups d1-c1, d2-c2, and d3-c3, we can calculate the average thickness of sea ice d and the average sound speed in ice c.

6. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 2 to 5 is implemented.

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