Shallow water wave parameter measuring device and method based on pressure

Abstract

The invention discloses a shallow water wave parameter measuring device and measuring method based on pressure, and relates to the technical field of marine technology engineering surveying, the device comprises a telescopic support in the shape of an equilateral triangle, a sealed cabin located at the center position of the telescopic support, and pressure collecting cabins located at all corner positions of the telescopic support, the battery bin is located between the central position and the angular positions, and the supporting feet are installed at the angular positions respectively. The method is used for solving the problem that in the prior art, accuracy is poor when shallow water wave parameters are measured, and the accuracy of shallow water wave parameter measurement is improved.

Description

Technical Field

[0001] The present application relates to the technical field of marine technology engineering surveying, and in particular to a measuring device and method for shallow water wave parameters based on pressure. Background Art

[0002] Affected by the terrain, short-crested waves are dominant in shallow water, and the wave direction of the waves plays a very important role in the wave conditions. At present, most wave measurements are based on buoys to obtain wave parameters such as the directional spectrum. However, in shallow waters (water depth less than 10 m), stranding is likely to occur and it is greatly affected by the tide level, so it is not commonly used in shallow waters.

[0003] For shallow waters, wave parameters are usually obtained by measuring the seabed pressure and then converting it into wave parameters. However, based on a single pressure sensor, only parameters such as the wave surface elevation, characteristic wave height, and characteristic period of the waves can be obtained, and parameters such as the wave direction and directional spectrum of the waves cannot be obtained.

[0004] In order to obtain the wave direction and directional spectrum, the prior art measures the seabed pressure and sea current simultaneously, and assumes that the change of the sea current in a short time is completely caused by the waves, so as to obtain the wave direction and directional spectrum based on the wave spectrum measurement method (PUV method). However, the sea current in shallow waters is affected by the terrain and is very complex. This method of obtaining the wave direction and directional spectrum based on assumptions has poor applicability and low accuracy of the calculation results. Summary of the Invention

[0005] In view of the above problems and technical requirements, the applicant of the present application proposes a measuring device and method for shallow water wave parameters based on pressure, so as to solve the problem of poor accuracy in measuring shallow water wave parameters in the prior art and improve the accuracy of measuring shallow water wave parameters.

[0006] An embodiment of the present application provides a measuring device for shallow water wave parameters based on pressure. The device includes: a telescopic support in the shape of an equilateral triangle, a sealed cabin located at the central position of the telescopic support, a pressure acquisition cabin located at each corner position of the telescopic support, a battery cabin located between the central position and the corner positions, a support leg installed at each corner position, and a data processing module;

[0007] The support leg is used to fix the telescopic support at a preset measurement position in the shallow water area to be measured;

[0008] The sealed cabin includes: a time synchronizer, a compass, and a pressure sensor;

[0009] Each pressure acquisition cabin includes: a pressure sensor;

[0010] The battery compartment is used to store batteries, and the batteries are used to supply power to the devices in the sealed compartment and the devices in the pressure acquisition compartment;

[0011] The length of each side of the retractable bracket is obtained from the wavelength corresponding to the spectral peak period of the shallow water area to be measured, and the length is less than or equal to a preset multiple of the wavelength, where the preset value is a real number less than 1 and greater than 0;

[0012] The time synchronizer is used to make all pressure sensors operate simultaneously, ensuring that all pressure sensors have the same sampling frequency and sampling time;

[0013] Each pressure sensor is used to obtain the water pressure value and water depth corresponding to its location;

[0014] The compass is used to determine the position of each pressure sensor;

[0015] The data processing module is used to obtain the wave direction and direction spectrum based on the pressure time series, the water depth, and the positions of the pressure sensors, where the pressure time series is the pressure values monitored by all pressure sensors within a preset time period, and the water depth is the average value of the corresponding water depths within the preset time period.

[0016] For the measurement device of shallow water wave parameters based on pressure according to an embodiment of the present application, the data processing module is used to convert the pressure time series into a wave surface elevation series based on the water depth; calculate the direction spectrum by using the fast Fourier transform method based on the wave surface elevation series and the positions of each pressure sensor in the pressure acquisition compartment; and obtain the wave direction based on the direction spectrum.

[0017] For the measurement device of shallow water wave parameters based on pressure according to an embodiment of the present application, the data processing module is used to remove the trend term of each pressure time series to obtain a target pressure time series;

[0018] Perform fast Fourier transform on each parameter in the target pressure time series to obtain the pressure Fourier coefficients and frequencies; obtain the wave surface spectrum based on the pressure Fourier coefficients and the frequencies; perform inverse Fourier transform on the wave surface spectrum to obtain the wave surface elevation values, where the parameters include the pressure values monitored by the corresponding pressure sensors;

[0019] Combine the four obtained wave surface elevation values to obtain the wave surface elevation series.

[0020] A pressure-based measuring device for shallow water wave parameters according to an embodiment of the present application, wherein the data processing module is configured to calculate the slope corresponding to each parameter of the pressure time series and the time stamp corresponding to the parameter based on a first calculation formula, and calculate the intercept corresponding to the parameter based on a second calculation formula; obtain the detrended pressure value based on the slope, the intercept and a third calculation formula; combine the detrended pressure values to obtain the target pressure time series;

[0021] Wherein, the first calculation formula includes:

[0022]

[0023] Wherein, k i represents the slope corresponding to the i-th parameter, i = 0, 1, 2, 3, n represents the number of pressure values of the parameter within a preset time period, t j represents the time stamp of the j-th pressure value in the parameter, p ij represents the j-th pressure value in the parameter;

[0024] Wherein, the second calculation formula includes:

[0025]

[0026] Wherein, c i represents the intercept corresponding to the i-th parameter;

[0027] Wherein, the third calculation formula includes:

[0028]

[0029] Wherein, represents the i-th detrended parameter, t represents the preset time period, p i represents the i-th parameter.

[0030] 5. The pressure-based measuring device for shallow water wave parameters according to claim 3, wherein the data processing module is configured to obtain a wave surface spectrum based on the pressure Fourier coefficient, the frequency and a fourth calculation formula; obtain the wave surface elevation value based on a fifth calculation formula;

[0031] Wherein, the fourth calculation formula includes:

[0032] F i = F pi / K p ;

[0033] Wherein, F i represents the wave surface spectrum corresponding to the i-th parameter, F pi represents the pressure Fourier coefficient, wherein, k represents the wave number corresponding to the frequency, and h i represents the water depth monitored by the i-th pressure sensor;

[0034] wherein, the fifth calculation formula includes:

[0035] η i = iFFT(F i );

[0036] wherein, η i represents the wave surface elevation value, and iFFT() represents the inverse Fourier transform.

[0037] For the pressure-based shallow water wave parameter measurement device according to an embodiment of the present application, the data processing module is configured to calculate the cross-spectrum S pq (f) = FFT(η p )FFT * (η q );

[0038] wherein, FFT() represents the Fourier transform, the superscript "*" represents taking the conjugate, any two points include the p point and the q point, and the wave surface elevation sequence includes η p and η q , and at the same time, the conjugate cross-spectrum

[0039] Calculate the distance D pq between any two points and the angle β pq between the line connecting the two points and the due north direction;

[0040] Based on D pq and β pq calculate the following coefficients:

[0041] A 0pq = J 0 (dD pq );

[0042] A 1pq = 2cos(β pq )J 1 (dD pq );

[0043] A 2pq = 2cos(2β pq )J 2 (dD pq );

[0044] B 1pq = 2sin(β pq )J 1 (dD pq );

[0045] B 2pq =2sin(2β pq )J 2 (dD pq );

[0046] Among them, J i is the Jacobian function of order i, and d is the wave number corresponding to each frequency;

[0047] For each frequency f, the system of simultaneous equations:

[0048]

[0049] where, for each f, the unknown number is [a 0 ,a 1 ,a 2 ,b 1 ,b 2 ], using the least squares method to fit [a 0 ,a 1 ,a 2 ,b 1 ,b 2 ];

[0050] Use the sixth calculation formula to get the wave direction;

[0051] Among them, the sixth calculation formula includes:

[0052]

[0053] According to the pressure-based shallow water wave parameter measurement device of one embodiment of the present application, the data processing module is used to obtain the spectral density based on the seventh calculation formula;

[0054] Among them, the seventh calculation formula includes:

[0055]

[0056] Where F(f,θ) is the directional spectrum, f is the frequency, and θ is the wave direction;

[0057] Based on the eighth calculation formula, the significant wave height is obtained;

[0058] Among them, the eighth calculation formula includes:

[0059]

[0060] The spectrum peak frequency is obtained based on the ninth calculation formula;

[0061] f p = f ( S ( f ) = max ( S ( f ) ) );

[0062] Write the direction spectrum as F(f,θ)=S(f)D(θ) and expand Calculate the main wave direction θ 0 =arctan(b 1 / a 1 );

[0063] Where S(f) is the spectral density, D(θ) is the directional function, and a and b are the expansion coefficients.

[0064] According to the pressure-based shallow water wave parameter measurement device of one embodiment of the present application, the data processing module is communicatively connected with each of the pressure sensors and the compass respectively;

[0065] Each of the pressure sensors is used to send the acquired water pressure value and water depth to the data processing module;

[0066] The compass is used to send the position and tilt angle of each pressure sensor to the data processing module;

[0067] The data processing module is used to process the received pressure time series, the water depth and the position of the pressure sensor based on a preset time period to obtain the wave direction and the directional spectrum.

[0068] According to the pressure-based shallow water wave parameter measurement device of one embodiment of the present application, the retractable bracket is provided with an interface for data export;

[0069] The data processing module includes: a data import unit;

[0070] The data import unit is used to import the pressure time series, the water depth and the position of the pressure sensor in response to a data import instruction; and process the pressure time series, the water depth and the position of the pressure sensor based on a preset time period to obtain the wave direction and the directional spectrum.

[0071] The embodiment of the present application is based on the shallow water wave parameter measurement device based on pressure provided in any of the above embodiments, and further provides a wave parameter measurement method, the method comprising:

[0072] Obtain pressure time series, water depth and location of each pressure sensor;

[0073] Based on the pressure time series, the water depth and the position of the pressure sensor, the wave direction and the direction spectrum are obtained, wherein the pressure time series is the pressure value monitored by all pressure sensors within a preset time period, and the water depth is the average value of the corresponding water depth within the preset time period.

[0074] The embodiment of the present application provides a pressure-based shallow water wave parameter measurement device and measurement method, the measurement device includes: a retractable bracket in the shape of an equilateral triangle, a sealed cabin located at the center of the retractable bracket, a pressure collection chamber located at each angular position of the retractable bracket, a battery compartment located between the center position and the angular position, a support foot installed at each angular position, and a data processing module; the data processing module is used to obtain the wave direction and directional spectrum based on the pressure time series obtained from the pressure value measured by the pressure sensor, the water depth and the position of the pressure sensor. By monitoring the data, the present application can directly, quickly and accurately obtain the wave direction and directional spectrum, thereby solving the problem of accuracy difference in measuring shallow water wave parameters in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0076] Figure 1 It is a schematic diagram of the structure of a pressure-based shallow water wave parameter measurement device provided in an embodiment of the present application;

[0077] Figure 2 It is a schematic diagram of the flow chart of the wave parameter measurement method provided in the embodiment of the present application;

[0078] Figure 3 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0079] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are 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 invention.

[0080] The present application embodiment provides a device for measuring shallow water wave parameters based on pressure, such as Figure 1 As shown, the measuring device includes: a retractable bracket 10 in the shape of an equilateral triangle, a sealed cabin 20 located at the center of the retractable bracket, a pressure collection chamber 30 located at each angular position of the retractable bracket, a battery chamber 40 located between the center position and the angular position, a support leg 50 installed at each angular position, and a data processing module 60.

[0081] The support legs 50 are used to fix the retractable support 10 at a preset measurement position of the shallow water area to be measured.

[0082] The sealed cabin 20 includes: a time synchronizer, a compass and a pressure sensor.

[0083] Each pressure collection chamber includes: a second pressure sensor.

[0084] The battery compartment 40 is used to store batteries, and the batteries are used to power the devices in the sealed cabin 20 and the devices in the pressure collection compartment 30 .

[0085] The length of each side of the retractable bracket 10 is obtained by the wavelength corresponding to the spectrum peak period of the shallow water area to be measured, and the length is less than or equal to a preset value times the wavelength, where the preset value is a real number less than 1 and greater than 0.

[0086] The time synchronizer is used to make all pressure sensors operate simultaneously to ensure that all pressure sensors have the same sampling frequency and sampling time.

[0087] Each pressure sensor is used to obtain the water pressure value and water depth corresponding to the location.

[0088] A compass is used to determine the position of each pressure sensor.

[0089] The data processing module 60 is used to obtain the wave direction and direction spectrum based on the pressure time series, water depth and the position of the pressure sensor, wherein the pressure time series is the pressure value monitored by all pressure sensors within a preset time period, and the water depth is the average value of the corresponding water depth within the preset time period.

[0090] Specifically, in layman's terms, the measuring device is an equilateral triangle bracket, with a data acquisition device, a time synchronization module, a compass compartment and a pressure sensor compartment at the center of the bracket. There are pressure sensor compartments at the three corners. There is a battery compartment between the three corners and the center point. The side length of the triangle is Not exceeding 0.3 times the wavelength corresponding to the spectrum peak period of the sea area to be measured.

[0091] Among them, the bracket: made of 304 steel, including three legs, a base, a sealed cabin (for placing the data collector, time synchronization module, compass compartment and battery compartment) and three pressure sensor compartments. The pressure resistance is not less than 30m. Pressure sensor: used to measure the wave surface rise and pressure value. The measurement range is 0.1-15m, and the accuracy is higher than or equal to ±0.5% FS. Data collector, time synchronization module and compass: used for 4 pressure sensor data collection and storage, time synchronization, and recording the direction and position of 4 pressure sensors. Battery: used to provide power for pressure sensor, data collector, time synchronization module and compass module, lead-acid battery or lithium battery can be used.

[0092] The embodiment of the present application provides a pressure-based shallow water wave parameter measurement device and measurement method, the measurement device includes: a retractable bracket 10 in the shape of an equilateral triangle, a sealed cabin 20 located at the center of the retractable bracket, a pressure collection chamber 30 located at each angular position of the retractable bracket, a battery compartment 40 located between the center position and the angular position, a support leg 50 installed at each angular position, and a data processing module 60; the data processing module 60 is used to obtain the wave direction and directional spectrum based on the pressure time series obtained from the pressure value measured by the pressure sensor, the water depth and the position of the pressure sensor. By monitoring the data, the present application can directly, quickly and accurately obtain the wave direction and directional spectrum, thereby solving the problem of accuracy difference in measuring shallow water wave parameters in the prior art.

[0093] In a specific embodiment, the data processing module 60 is integrated on the measuring device body, and the data processing module 60 is respectively connected to each pressure sensor and the compass for communication. Each pressure sensor is used to send the acquired water pressure value and water depth to the data processing module 60. The compass is used to send the position and inclination angle of each pressure sensor to the data processing module 60. The data processing module 60 is used to process the received pressure time series, water depth and position of the pressure sensor based on a preset time period to obtain the wave direction and direction spectrum.

[0094] In a specific embodiment, the data processing module 60 is not integrated on the measuring device body, and an interface for data export is provided in the retractable support 10. The data processing module 60 includes: a data import unit.

[0095] The data import unit is used to import the pressure time series, water depth and the position of the pressure sensor in response to the data import instruction; and process the pressure time series, water depth and the position of the pressure sensor based on a preset time period to obtain the wave direction and direction spectrum.

[0096] In a specific embodiment, the data processing module 60 is used to convert the pressure time series into a wave surface rise sequence based on the water depth; based on the wave surface rise sequence and the position of each pressure sensor in the pressure acquisition chamber, the directional spectrum is calculated using the fast Fourier transform method; and the wave direction is obtained based on the directional spectrum.

[0097] In a specific embodiment, the data processing module 60 is used to remove the trend item of each pressure time series to obtain a target pressure time series.

[0098] Perform fast Fourier transform on each parameter in the target pressure time series to obtain the pressure Fourier coefficient and frequency; obtain the wavefront spectrum based on the pressure Fourier coefficient and frequency; perform inverse Fourier transform on the wavefront spectrum to obtain the wavefront rise value; combine the four obtained wavefront rise values ​​to obtain the wavefront rise sequence.

[0099] The parameters include the pressure value monitored by the corresponding pressure sensor.

[0100] In a specific embodiment, the data processing module 60 is used to calculate the slope corresponding to the parameter based on a first calculation formula, and calculate the intercept corresponding to the parameter based on a second calculation formula for each parameter of the pressure time series and the timestamp corresponding to the parameter; obtain the pressure value after removing the trend based on the slope, the intercept and the third calculation formula; and combine the pressure values ​​after removing the trend to obtain the target pressure time series.

[0101] The first calculation formula is shown in formula (1):

[0102]

[0103] Among them, k i represents the slope corresponding to the i-th parameter, i=0,1,2,3, n represents the number of pressure values ​​of the parameter in the preset time period, t j Indicates the timestamp of the j-th pressure value in the parameter, p ij Represents the jth pressure value in the parameter.

[0104] The second calculation formula is shown in formula (2):

[0105]

[0106] Among them, c i Represents the intercept corresponding to the i-th parameter.

[0107] The third calculation formula is shown in formula (3):

[0108]

[0109] in, represents the parameter after detrending the ith time, t represents the preset time period, and p i Represents the i-th parameter.

[0110] In a specific embodiment, the data processing module 60 is used to obtain the wavefront spectrum based on the pressure Fourier coefficient, the frequency and the fourth calculation formula; and to obtain the wavefront rise value based on the fifth calculation formula.

[0111] The fourth calculation formula is shown in formula (4):

[0112] F i =F pi / K p ……………………………………………………(4)

[0113] Among them, F irepresents the wave surface spectrum corresponding to the i-th parameter, F pi represents the pressure Fourier coefficient, Among them, k represents the wave number corresponding to the frequency, h i Represents the water depth monitored by the i-th pressure sensor.

[0114] The fifth calculation formula is shown in formula (5):

[0115] η i =iFFT(F i )…………………………………………(5)

[0116] Among them, η i represents the wavefront height, and iFFT() represents inverse Fourier transform.

[0117] In a specific embodiment, the data processing module is used to calculate the cross spectrum S of the wave surface rise sequence of any two points pq (f) = FFT(η p )FFT * (η q ).

[0118] Wherein, FFT() represents Fourier transform, the superscript “*” represents conjugation, any two points include point p and point q, and the wavefront rise sequence includes η p and η q , and the conjugate cross spectrum is calculated at the same time

[0119] Calculate the distance D between any two points pq The angle β between the line connecting the two points and the north direction pq .

[0120] Based on D pq and β pq The following coefficients are calculated:

[0121] A 0pq =J 0 (dD pq ).

[0122] A 1pq =2cos(β pq )J 1 (dD pq ).

[0123] A 2pq =2cos(2β pq )J 2 (dD pq ).

[0124] B 1pq =2sin(β pq)J 1 (dD pq ).

[0125] B 2pq =2sin(2β pq )J 2 (dD pq ).

[0126] Among them, J i is the Jacobian function of order i, and d is the wave number corresponding to each frequency.

[0127] For each frequency f, the system of simultaneous equations:

[0128]

[0129] where, for each f, the unknown number is [a 0 ,a 1 ,a 2 ,b 1 ,b 2 ], using the least squares method to fit [a 0 ,a 1 ,a 2 ,b 1 ,b 2 ].

[0130] Use the sixth calculation formula to get the wave direction;

[0131] The sixth calculation formula is shown in formula (6):

[0132]

[0133] Specifically, the measuring device is placed in water, the device (measuring device) is turned on, and the four pressure sensors are started to work at the same time through the time synchronization module, and the four pressure sensors are set to have the same sampling frequency and sampling time. After a preset time period, the pressure time series and average water depth of the four pressure sensors are obtained.

[0134] When the device is turned on, turn on the compass at the same time and record the direction and inclination angle of the four pressure sensors. Calculate the distance between the sensors at the three corners and the sensor at the center based on the relative position, direction and inclination between the pressure sensors. Let the center position be (0,0), the X axis point to the east direction, and the Y axis point to the north direction, and the positions of the remaining three sensors are (x 1 ,y 1 )、(x 2 ,y 2 ) and (x 3 ,y 3 ).

[0135] In a specific embodiment, the data processing module is used to obtain the spectral density based on the seventh calculation formula.

[0136] The seventh calculation formula is shown in formula (7):

[0137]

[0138] Where F(f,θ) is the directional spectrum, f is the frequency, and θ is the wave direction.

[0139] The significant wave height is obtained based on the eighth calculation formula.

[0140] The eighth calculation formula is shown in formula (8):

[0141]

[0142] The spectrum peak frequency is obtained based on the ninth calculation formula.

[0143] f p =f(S(f)=max(S(f)))……(9)

[0144] Write the direction spectrum as F(f,θ)=S(f)D(θ) and expand Calculate the main wave direction θ 0 =arctan(b 1 / a 1 ).

[0145] Where S(f) is the spectral density, D(θ) is the directional function, and a and b are the expansion coefficients.

[0146] The present application also provides a wave parameter measurement method, which is applied to the pressure-based shallow water wave parameter measurement device described in any of the above embodiments, such as Figure 2 As shown, the method includes:

[0147] Step 201, obtaining the pressure time series, water depth and the position of each pressure sensor.

[0148] Step 202, based on the pressure time series, the water depth and the position of the pressure sensor, obtain the wave direction and the directional spectrum.

[0149] The pressure time series is the pressure values ​​monitored by all pressure sensors within a preset time period, and the water depth is the average value of the corresponding water depth within the preset time period.

[0150] Figure 3 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 3As shown, the electronic device may include: a processor 301, a communications interface 302, a memory 303 and a communication bus 304, wherein the processor 301, the communications interface 302 and the memory 303 communicate with each other through the communication bus 304. The processor 301 may call the logic instructions in the memory 303 to execute the wave parameter measurement method.

[0151] In addition, the logic instructions in the above-mentioned memory 303 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0152] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the wave parameter measurement methods provided by the above-mentioned methods.

[0153] On the other hand, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to execute the wave parameter measurement method provided in the above-mentioned embodiments.

[0154] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0155] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0156] Finally, it should be noted that the above is only the preferred implementation of the present application, and the present application is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present application should be considered to be included in the scope of protection of the present application.

Claims

1. A pressure-based shallow water wave parameter measurement device, characterized in that: The device comprises: a retractable support in the shape of an equilateral triangle, a sealed cabin located at the center of the retractable support, a pressure collection chamber located at each corner of the retractable support, a battery chamber located between the center and the corner, a support leg installed at each corner, and a data processing module; The legs are used to fix the retractable bracket at a preset measurement position of the shallow water area to be measured; The sealed cabin includes: time synchronizer, compass and pressure sensor; Each pressure collection chamber includes: a pressure sensor; The battery compartment is used to store batteries, and the batteries are used to power the devices in the sealed cabin and the devices in the pressure collection cabin; The length of each side of the retractable bracket is obtained by the wavelength corresponding to the spectrum peak period of the shallow water area to be measured, and the length is less than or equal to a preset value times the wavelength, wherein the preset value is a real number less than 1 and greater than 0; Time synchronizer, used to make all pressure sensors work simultaneously, ensuring that all pressure sensors have the same sampling frequency and sampling time; Each pressure sensor is used to obtain the water pressure value and water depth corresponding to the location; a compass, used to determine the position of each pressure sensor; The data processing module is used to obtain the wave direction and direction spectrum based on the pressure time series, water depth and the position of the pressure sensor, wherein the pressure time series is the pressure value monitored by all pressure sensors within a preset time period, and the water depth is the average value of the corresponding water depth within the preset time period.

2. The pressure-based shallow water wave parameter measuring device according to claim 1, characterized in that: The data processing module is used to convert the pressure time series into a wave surface rise sequence based on the water depth; calculate the directional spectrum using the fast Fourier transform method based on the wave surface rise sequence and the position of each pressure sensor in the pressure acquisition chamber; and obtain the wave direction based on the directional spectrum.

3. The pressure-based shallow water wave parameter measuring device according to claim 2, characterized in that: The data processing module is used to remove the trend item of each pressure time series to obtain a target pressure time series; Performing a fast Fourier transform on each parameter in the target pressure time series to obtain a pressure Fourier coefficient and a frequency; obtaining a wavefront spectrum based on the pressure Fourier coefficient and the frequency; performing an inverse Fourier transform on the wavefront spectrum to obtain a wavefront rise value, wherein the parameter includes a pressure value monitored by a corresponding pressure sensor; The four wave surface rise values ​​obtained are combined to obtain the wave surface rise sequence.

4. The pressure-based shallow water wave parameter measuring device according to claim 3, characterized in that: The data processing module is used to calculate, for each parameter of the pressure time series and the timestamp corresponding to the parameter, a slope corresponding to the parameter based on a first calculation formula, and to calculate an intercept corresponding to the parameter based on a second calculation formula; Obtaining a pressure value after removing the trend based on the slope, the intercept and a third calculation formula; Combining the pressure values ​​after removing the trend to obtain the target pressure time series; The first calculation formula includes: Among them, k i represents the slope corresponding to the i-th parameter, i = 0, 1, 2, 3, n represents the number of pressure values ​​of the parameter within a preset time period, t j represents the timestamp of the j-th pressure value in the parameter, p ij represents the jth pressure value in the parameter; The second calculation formula includes: Among them, c i Represents the intercept corresponding to the i-th parameter; Wherein, the third calculation formula includes: in, represents the parameter after detrending the ith time, t represents the preset time period, and p i Represents the i-th parameter.

5. The pressure-based shallow water wave parameter measuring device according to claim 3, characterized in that: The data processing module is used to obtain a wave surface spectrum based on the pressure Fourier coefficient, the frequency and a fourth calculation formula; Based on the fifth calculation formula, the wave surface rise value is obtained; Wherein, the fourth calculation formula includes: F i =F pi / K p ; Among them, F i represents the wave surface spectrum corresponding to the i-th parameter, F pi represents the pressure Fourier coefficient, Wherein, k represents the wave number corresponding to the frequency, h i represents the water depth monitored by the i-th pressure sensor; Wherein, the fifth calculation formula includes: or i =iFFT(F i ); Among them, η i represents the wavefront height, and iFFT() represents inverse Fourier transform.

6. The pressure-based shallow water wave parameter measuring device according to claim 2, characterized in that: The data processing module is used to calculate the cross spectrum S of the wave surface rise sequence of any two points pq (f) = FFT(η p )FFT * (η q ); Wherein, FFT() represents Fourier transform, the superscript "*" represents conjugation, any two points include point p and point q, and the wavefront rise sequence includes η p and η q , and the conjugate cross spectrum is calculated at the same time Calculate the distance D between any two points pq The angle β between the line connecting the two points and the north direction pq ; Based on D pq and β pq The following coefficients are calculated: A 0pq =J0(dD pq ); A 1pq =2cos(β pq )J1(dD pq ); A 2pq =2cos(2β pq )J2(dD pq ); B 1pq =2sin(β pq )J1(dD pq ); B 2pq =2sin(2β pq )J2(dD pq ); Among them, J i is the Jacobian function of order i, and d is the wave number corresponding to each frequency; For each frequency f, the system of simultaneous equations: For each f, the unknown number is [a0, a1, a2, b1, b2], and the least squares method is used to fit [a0, a1, a2, b1, b2]; Use the sixth calculation formula to get the wave direction; Among them, the sixth calculation formula includes:

7. The pressure-based shallow water wave parameter measuring device according to claim 2, characterized in that: The data processing module is used to obtain the spectral density based on the seventh calculation formula; Among them, the seventh calculation formula includes: Where F(f,θ) is the directional spectrum, f is the frequency, and θ is the wave direction; Based on the eighth calculation formula, the significant wave height is obtained; Among them, the eighth calculation formula includes: The spectrum peak frequency is obtained based on the ninth calculation formula; f p =f(S(f)=max(S(f))); Write the direction spectrum as F(f,θ)=S(f)D(θ) and expand Calculate the main wave direction θ0 = arctan(b1 / a1); Where S(f) is the spectral density, D(θ) is the directional function, and a and b are the expansion coefficients.

8. The pressure-based shallow water wave parameter measuring device according to any one of claims 1 to 7, characterized in that: The data processing module is respectively connected to each of the pressure sensors and the compass for communication; Each of the pressure sensors is used to send the acquired water pressure value and water depth to the data processing module; The compass is used to send the position and tilt angle of each pressure sensor to the data processing module; The data processing module is used to process the received pressure time series, the water depth and the position of the pressure sensor based on a preset time period to obtain the wave direction and the directional spectrum.

9. The pressure-based shallow water wave parameter measuring device according to any one of claims 1 to 7, characterized in that: The retractable bracket is provided with an interface for data export; The data processing module includes: a data import unit; The data import unit is used to import the pressure time series, the water depth and the position of the pressure sensor in response to a data import instruction; and process the pressure time series, the water depth and the position of the pressure sensor based on a preset time period to obtain the wave direction and the directional spectrum.

10. A wave parameter measurement method based on the pressure-based shallow water wave parameter measurement device according to any one of claims 1 to 9, characterized in that: The method comprises: Obtain pressure time series, water depth and location of each pressure sensor; Based on the pressure time series, the water depth and the position of the pressure sensor, the wave direction and the direction spectrum are obtained, wherein the pressure time series is the pressure value monitored by all pressure sensors within a preset time period, and the water depth is the average value of the corresponding water depth within the preset time period.

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