Dolphin sound driving method, system and device based on feedback adjustment of underwater acoustic signal

Abstract

The application discloses a dolphin sound driving method, system and equipment based on underwater acoustic signal feedback adjustment, and relates to the field of marine ecological protection.According to the hearing threshold curve characteristics of dolphins, the application adopts a superimposed signal of a downward frequency sweeping signal and a high-speed yacht noise signal as an artificial synthetic sound wave for sound driving, and in order to avoid the situation that the sound driving effect of dolphins is significantly reduced or disappears with time under continuous sound wave stimulation (because dolphins are adaptive to sound), the application method designs an amplitude frequency shifter based on Hilbert transform, and adds a feedback adjustment mechanism for the signal to simulate the frequency shift and amplitude change of the real ship noise propagation, so that the variability of the emitted sound wave frequency and amplitude is maintained.Therefore, the application method can effectively drive dolphins for a long time, so that the purpose of protecting dolphins from being hurt in underwater engineering activities is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of marine ecological protection, and particularly relates to a dolphin sound driving method, system and equipment based on underwater acoustic signal feedback adjustment. BACKGROUND

[0002] Dolphins are key protected animals and play an indispensable role in the marine ecosystem. They can maintain the balance of the ecosystem and also drive the development of the tourism industry as ornamental animals. In addition, the sonar system of dolphins has great research value for humans. Since dolphins like to live in near-shore shallow waters and waters rich in fish, there is an overlap with the distribution range of various marine economic activities of humans, leading to an increasing conflict between dolphins and human activities. When humans carry out blasting operations, build bridges, and construct offshore wind farms and other construction methods in the sea, they can cause serious damage to the middle and inner ears of dolphins, and even endanger the lives of dolphins. Therefore, it is particularly important to drive dolphins away from dangerous waters during offshore marine engineering construction.

[0003] With the increasing frequency of human activities in the sea in recent years, many dolphins have been dying due to human factors, and it is urgent to protect dolphins. At present, there are various ways to protect dolphins during human engineering activities, which have a certain protective effect, but still have various drawbacks, such as the method of fish barriers which can cause damage to the seagrass ecosystem, and the method of electrically driving dolphins which can cause harm to dolphins, especially to young dolphins. Therefore, new technologies for driving dolphins are urgently needed for research and development. Sound driving technology is one of the emerging and extremely important technologies for driving and protecting dolphins in the sea in recent years. This technology avoids the drawbacks of other dolphin driving technologies.

[0004] The sound driving of dolphins refers to a technical method of emitting specific sound waves to guide and drive dolphins in a selected area in the sea. In recent years, the sound driving technology has developed rapidly, and can be applied to more marine species. It can be used to drive marine fish and dolphins. The sound wave emission signal type used to drive dolphins mainly includes two types. One is analog noise, such as ordinary ship noise, swimming noise, intermittent knocking bamboo sound, and detonator explosion sound. The advantage is that it has positive tropism to dolphins, and the disadvantage is that the function of this type of sound wave is fixed (often through recording and broadcasting) or difficult to control, and it cannot be adjusted according to the specific sea conditions. The actual application is limited. The other is artificial synthesized sound wave. For dolphins, 0-100 kHz single frequency continuous wave, square wave, linear frequency modulation wave, pulse wave and the like are mainly used. This type of waveform is easy to produce, easy to control parameters and has obvious effect in the initial stage of driving. However, this type of artificial synthesized sound wave has single waveform or frequency and cannot adjust the frequency and amplitude of the signal in real time. The driving effect of dolphins decreases significantly over time, and the artificial synthesized sound may even have the opposite effect (i.e. attracting dolphins) when driving dolphins away. SUMMARY

[0005] In view of the problems in the background art, the present application provides a dolphin sound driving method, system and device based on underwater acoustic signal feedback adjustment to effectively drive dolphins for a long time and achieve the purpose of protecting dolphins from being harmed in underwater engineering activities.

[0006] To achieve the above object, the present application provides the following solutions:

[0007] In one aspect, the present application provides a dolphin sound driving method based on underwater acoustic signal feedback adjustment, comprising:

[0008] generating a downward frequency signal according to the frequency range of the dolphin hearing threshold, and generating an initial high-speed yacht noise signal according to the hearing threshold curve of the dolphin;

[0009] superimposing the downward frequency signal and the initial high-speed yacht noise signal, and emitting the superimposed signal through a cylindrical underwater acoustic transducer for driving dolphins;

[0010] receiving the ocean ambient noise through a spherical receiving hydrophone and calculating the frequency band sound pressure level of the ocean ambient noise;

[0011] calculating the amplitude adjustment coefficient of the superimposed signal according to the frequency band sound pressure level of the ocean ambient noise;

[0012] calculating the frequency shift adjustment coefficient of the high-speed yacht noise signal according to the duration of the superimposed signal emission;

[0013] feedback adjusting and updating the amplitude and frequency shift adjuster designed based on Hilbert transform according to the amplitude adjustment coefficient and the frequency shift adjustment coefficient.

[0014] The new superimposed signal is obtained by frequency shift processing and amplitude adjustment using the variable amplitude frequency shifter, and the step of emitting the superimposed signal through the cylindrical underwater acoustic transducer for driving dolphins is returned.

[0015] Optionally, the method further comprises:

[0016] The formula L is used to calculate the frequency band sound pressure level L pf of the ocean ambient noise; wherein P f is the sound pressure value of the sound wave of the ocean ambient noise within the bandwidth; and P0 is the reference sound pressure.

[0017] Optionally, the method further comprises:

[0018] The formula k = V is used to calculate the amplitude adjustment coefficient k of the superimposed signal according to the frequency band sound pressure level L pf of the ocean ambient noise; wherein V max is the maximum voltage value that the cylindrical underwater acoustic transducer can receive.

[0019] Optionally, the method further comprises:

[0020] The formula r = T is used to calculate the frequency shift adjustment coefficient r of the high-speed yacht noise signal according to the time length T of the emission of the superimposed signal; wherein T max is the target time length of the emission of the superimposed signal.

[0021] Optionally, the method further comprises:

[0022] The formula A is used to calculate the amplitude adjustment coefficient A i of the superimposed signal in the i-th feedback adjustment according to the amplitude adjustment coefficient k; wherein A max is the maximum amplitude of the superimposed signal set.

[0023] The formula Δf i = r × Δf max is used to calculate the frequency shift Δf i of the high-speed yacht noise signal in the i-th feedback adjustment according to the frequency shift adjustment coefficient r; wherein Δf max is the maximum frequency shift of the high-speed yacht noise signal in one feedback adjustment.

[0024] The amplitude adjustment coefficient Ai and frequency shift amount Δf i to update the variable-amplitude frequency shifter designed based on the Hilbert transform where H[·] is a Hilbert transform symbol; x(t) is a high-speed fast-boat noise signal input to the variable-amplitude frequency shifter; z(t) is a down-sweep signal input to the variable-amplitude frequency shifter; and y(t) is a superimposed signal output from the variable-amplitude frequency shifter.

[0025] In another aspect, the application also provides a dolphin sound driving system based on underwater acoustic signal feedback adjustment, comprising:

[0026] a signal generation module configured to generate a down-sweep signal according to a frequency range of a dolphin hearing threshold and generate an initial high-speed fast-boat noise signal according to a hearing threshold curve of the dolphin;

[0027] a signal superimposition and emission module configured to superimpose the down-sweep signal and the initial high-speed fast-boat noise signal, and emit the superimposed signal through a cylindrical underwater acoustic transducer for driving the dolphin;

[0028] a signal reception and calculation module configured to receive ocean ambient noise through a spherical receiving hydrophone and calculate a frequency band sound pressure level of the ocean ambient noise;

[0029] an amplitude adjustment coefficient calculation module configured to calculate an amplitude adjustment coefficient of the superimposed signal according to the frequency band sound pressure level of the ocean ambient noise;

[0030] a frequency shift adjustment coefficient calculation module configured to calculate a frequency shift adjustment coefficient of the high-speed fast-boat noise signal according to a time length of the emission of the superimposed signal;

[0031] a variable-amplitude frequency shifter updating module configured to feedback adjust and update the variable-amplitude frequency shifter designed based on the Hilbert transform according to the amplitude adjustment coefficient and the frequency shift adjustment coefficient;

[0032] a superimposed signal feedback adjustment module configured to obtain a new superimposed signal after frequency shift processing and amplitude adjustment by the variable-amplitude frequency shifter, and return to the step of emitting the superimposed signal through the cylindrical underwater acoustic transducer for driving the dolphin.

[0033] In another aspect, the application also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the dolphin sound driving method based on underwater acoustic signal feedback adjustment when executing the computer program.

[0034] Optionally, the memory is a non-transitory computer readable storage medium.

[0035] According to the embodiments of the application, the following technical effects are achieved:

[0036] The application provides a dolphin sound driving method, system and device based on underwater acoustic signal feedback adjustment, according to the hearing threshold curve characteristics of dolphins, a superimposed signal of a downward frequency sweeping signal and a high-speed yacht noise signal is used as an artificial synthetic sound wave for sound driving, and in order to avoid the case that the sound driving effect of dolphins is significantly reduced or disappears with time (because dolphins are adaptive to sound) under continuous sound wave stimulation, a variable amplitude frequency shifter is designed based on Hilbert transform in the method, a feedback adjustment mechanism for the signal is added to simulate the frequency shift and amplitude change of real ship noise propagation, so as to maintain the variability of the emission sound wave frequency and amplitude. Therefore, the method of the application can effectively drive dolphins for a long time, so as to achieve the purpose of protecting dolphins from being hurt in underwater engineering activities. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0038] Figure 1 A flow chart of a dolphin sound driving method based on underwater acoustic signal feedback adjustment provided by the present application;

[0039] Figure 2 A principle schematic diagram of a dolphin sound driving method based on underwater acoustic signal feedback adjustment provided by the present application;

[0040] Figure 3 A hearing threshold curve diagram of dolphins provided by the present application;

[0041] Figure 4 A time-frequency spectrum diagram of an initial high-speed yacht noise HSN0 provided by the present application;

[0042] Figure 5 A feedback adjustment principle diagram based on a frequency shift adjustment coefficient r and an amplitude adjustment coefficient k provided by the present application;

[0043] Figure 6 An implementation block diagram of a variable amplitude frequency shifter H(ω;t) provided by the present application;

[0044] Figure 7 A change schematic diagram of the number of dolphin click signals before and after sound driving provided by the present application. DETAILED DESCRIPTION

[0045] Clearly, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present application.

[0046] The purpose of the present application is to provide a dolphin sound driving method, system and device based on underwater acoustic signal feedback adjustment, to effectively drive dolphins for a long time, and to achieve the purpose of protecting dolphins from injury in underwater engineering activities.

[0047] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below in combination with the drawings and specific embodiments.

[0048] Figure 1 A flowchart of a dolphin sound driving method based on underwater acoustic signal feedback adjustment provided by the present application, Figure 2 A principle diagram of a dolphin sound driving method based on underwater acoustic signal feedback adjustment provided by the present application. Referring to Figure 1 and Figure 2 A dolphin sound driving method based on underwater acoustic signal feedback adjustment, comprising:

[0049] Step 1: generating a downward frequency signal according to the frequency range of the dolphin hearing threshold, and generating an initial high-speed speedboat noise signal according to the hearing threshold curve of the dolphin.

[0050] Dolphins play a significant role in the ecosystem, and their sonar system has important reference value for the development of human sonar. In addition, the sonar sound generation system of dolphins is closely related to their own hearing characteristics, so the hearing threshold sensitivity of dolphins has great significance for guiding the sound driving technology of dolphins. The present application designs and feedback adjusts the sound driving signal based on the hearing threshold characteristics of dolphins. After a large number of experiments and research, it is found that the hearing characteristics of dolphins are roughly in the shape of a typical "V" shape, that is, there is a higher frequency band in the hearing threshold frequency range. For example, the Chinese white dolphin, in the frequency range of 0-10 kHz, the hearing threshold gradually increases, and the hearing sensitivity gradually decreases; in the frequency range of 10-45 kHz, the hearing threshold reaches the lowest value at 45 kHz; in the frequency range of 45-75 kHz, the hearing sensitivity slowly decreases, and in the frequency range of 76-100 kHz, the hearing sensitivity slowly increases, but the overall trend is stable; in the frequency range of 100-125 kHz, the hearing sensitivity of the Chinese white dolphin decreases significantly, and the hearing threshold continuously increases. For other dolphins, the overall appearance of the hearing threshold curve of cetaceans is U-shaped, and there is a most sensitive hearing threshold value, the value of orca is the lowest, which is 34 dB, and the value of Amazon dolphin is the highest, which is 51 dB. On the left side of the most sensitive hearing threshold value, the hearing sensitivity of cetaceans increases with the increase of frequency, and on the right side of the most sensitive hearing threshold value, the hearing sensitivity of cetaceans decreases with the increase of frequency. The upper limit of the hearing frequency of these cetaceans is greater than 100 kHz, and the upper limit of the hearing frequency of beluga whale and porpoise is even as high as 150 kHz.

[0051] According to the hearing threshold curve characteristics of dolphins, in the activity of sound driving dolphins in the influence area of underwater engineering (such as underwater blasting or piling engineering), the signal design emission end generates a downward frequency signal LFM1 (indicating the continuous spectrum part of the ship noise) according to the frequency range of the hearing threshold of dolphins; and generates an initial high-speed speedboat noise signal HSN0 according to the hearing threshold curve (the sensitivity of hearing to different frequency sound waves) of dolphins.

[0052] Specifically, the time domain waveform of the linear frequency modulation signal LFM1 is s(t), and the instantaneous frequency can be expressed as Wherein, θ(t) represents the phase waveform of the downward frequency signal LFM1 curve, and the amplitude is A; the starting frequency is f1, the ending frequency is f2, and f0 is the center frequency; μ is the modulation index, which is defined as the maximum frequency shift in the pulse width T L of the emission waveform, that is, the bandwidth B=f2-f1, that is Then:

[0053]

[0054] Dolphins are mammals, they use sound for orientation, communication and hunting. The hearing threshold of dolphins varies with species, age, gender, environment and other factors, but generally, the frequency range of the hearing threshold of dolphins is between 20Hz and 150kHz, as can be seen from the description of the time-domain waveform s(t) of LFM1 in formula (1), LFM1 can be determined by the starting frequency f1 and the ending frequency f2, such as Figure 5 In the example, the starting frequency f1 of the present application is set to 500Hz, and the ending frequency f2 is set to 150kHz, which basically meets the frequency range of the hearing threshold of dolphins. Of course, according to different species of dolphins, the starting frequency f1 and the ending frequency f2 can be changed according to the hearing threshold.

[0055] Figure 3 The hearing threshold curve of dolphins is shown, the horizontal coordinate is frequency, and the vertical coordinate is the sound pressure level that dolphins can hear. Figure 3 For the first increase and then decrease and then increase mode, there is a relatively high sensitive frequency in a specific frequency, in 0-10kHz, the hearing threshold gradually increases, and the hearing sensitivity gradually decreases; in 10-45kHz, the most sensitive frequency range is reached, and the hearing threshold reaches the lowest at 45kHz; in 45-75kHz, the hearing sensitivity slowly decreases, and in 76-100kHz, the hearing sensitivity slowly increases, but overall it tends to be stable; in the frequency range of 100-125kHz, the hearing sensitivity of Chinese white dolphins decreases significantly, and the hearing threshold continuously increases.

[0056] Further, the noise of high-speed yachts is a special kind of ship noise. Due to the quasi-periodic characteristics of mechanical noise and significant propeller noise, the noise spectrum often presents a line spectrum characteristic, as shown in Figure 4 As shown, the noise intensity of high-speed yachts is high, and the frequency distribution band is wide (when the speed is 15-40km / h, the noise frequency distribution is in the range of 1-125kHz), the underwater noise generated by the yacht is stronger when the speed is higher or the distance to the dolphin is closer, and the driving away effect is more obvious.

[0057] Therefore, the present application combines the hearing threshold curve characteristics of dolphins and the line spectrum characteristics of high-speed yacht noise spectrum, selects Figure 3 As shown in the hearing threshold curve, five frequency points (the five frequency points can cover the hearing threshold curve of dolphins and can represent the change of the hearing threshold of dolphins) are selected, and the initial high-speed yacht noise signal HSN0 generated can be composed of the following group of frequency components: 1kHz, 5kHz, 10kHz, 50kHz and 100kHz. Figure 4 That is, the time-frequency spectrum diagram of the initial high-speed yacht noise signal HSN0 calculated by short-time Fourier transform, as can be seen from the diagram, it has a line spectrum characteristic, and the sound energy is mainly distributed in each line spectrum.

[0058] Step 2: Superimpose the down-sweep signal and the initial high-speed boat noise signal, and transmit the superimposed signal through the cylindrical underwater acoustic transducer for driving away dolphins.

[0059] When starting to acoustically drive dolphins, superimpose the generated down-sweep signal LFM1 and the initial high-speed boat noise signal HSN0, and transmit the output waveform of the superimposed signal through the horizontally omnidirectional cylindrical underwater acoustic transducer for acoustically driving dolphins, so as to achieve the purpose of protecting dolphins in the underwater engineering influence area.

[0060] Step 3: Receive the ocean ambient noise through the spherical receiving hydrophone and calculate the frequency band sound pressure level of the ocean ambient noise.

[0061] As shown in Figure 5 , the spherical receiving hydrophone is placed below the cylindrical transducer for receiving the ocean ambient noise transmitted through the underwater acoustic channel during the transmission gap of the acoustic driving signal. After the received ocean ambient noise signal is processed through the preamplification, anti-aliasing filtering and A / D conversion circuit, a digital signal is obtained, so as to calculate the frequency band sound pressure level L pf of the ocean ambient noise.

[0062] The calculation formula of the frequency band sound pressure level L pf of the ocean ambient noise is as follows:

[0063]

[0064] In the formula, P f is the sound pressure value of the sound wave of the ocean ambient noise in the bandwidth, and the unit is Pa; P0 is the reference sound pressure, which is usually 1 uPa in underwater environment.

[0065] Step 4: Calculate the amplitude adjustment coefficient of the superimposed signal according to the frequency band sound pressure level of the ocean ambient noise.

[0066] According to the frequency band sound pressure level L pf obtained in step 3, the amplitude adjustment coefficient k of the superimposed signal is calculated, the amplitude adjustment coefficient k is inversely proportional to the frequency band sound pressure level L pf of the ocean ambient noise, and the calculation formula is as follows:

[0067]

[0068] In the formula, V max is the maximum voltage value that can be received by the cylindrical underwater acoustic transducer.

[0069] Step 5: Calculate the frequency shift adjustment coefficient of the high-speed boat noise signal according to the duration of the transmission of the superimposed signal.

[0070] The frequency shift adjustment coefficient r of the high-speed boat noise is calculated based on the duration T of the sound wave emission during the dolphin chasing activity. The frequency shift adjustment coefficient r is proportional to the duration T of the sound wave emission, and the calculation formula is as follows:

[0071]

[0072] Where T max The target duration for superimposed signal transmission.

[0073] Step 6: Feedback adjustment and update the variable amplitude frequency shifter based on the Hilbert transform design according to the amplitude adjustment coefficient and frequency shift adjustment coefficient.

[0074] like Figure 5 As shown in the figure (the waveform in the figure is the power spectrum of the transmitted superimposed signal sound wave), with the measured frequency band sound pressure level L of the marine environmental noise... pf The changes in amplitude and sound wave emission have been ongoing for a duration T. The amplitude adjustment coefficient k and frequency shift adjustment coefficient r are continuously calculated and updated, as shown in the following formulas:

[0075]

[0076] In the formula, T represents the duration of the superimposed signal sound wave emission during the acoustic driving activity. max The target duration set for the sound-based deterrence activity, Δf max Δf is the maximum frequency shift of the high-speed boat noise signal during a single feedback adjustment. i It is the frequency shift in the i-th round of feedback regulation; V max A is the maximum voltage value that the cylindrical underwater acoustic transducer can receive. max A is the maximum amplitude of the superimposed signal. i It is the amplitude adjustment coefficient of the superimposed signal in the i-th round of feedback regulation.

[0077] The amplitude adjustment coefficient k and frequency shift adjustment coefficient r calculated in steps 4 and 5 are used for feedback adjustment and to update the variable amplitude frequency shifter H(ω;t) designed based on the Hilbert transform. Specifically, according to the amplitude adjustment coefficient k, the formula is used... Calculate the amplitude adjustment coefficient A of the superimposed signal in the i-th round of feedback regulation. i Based on the frequency shift adjustment coefficient r, the formula Δf is used. i =r×Δf max Calculate the frequency shift Δf of the high-speed boat noise signal during the i-th round of feedback regulation. i According to the amplitude adjustment factor A i and frequency shift Δf i To update the amplitude-shifting frequency converter based on Hilbert transform design Where H[·] is the Hilbert transform symbol; x(t) is the high-speed boat noise signal input to the amplitude shifter; z(t) is the downsweep signal input to the amplitude shifter; and y(t) is the superimposed signal output by the amplitude shifter.

[0078] Step 7: After frequency shifting and amplitude adjustment using a variable amplitude frequency shifter, a new superimposed signal is obtained. Then, return to the step of transmitting the superimposed signal through a cylindrical underwater acoustic transducer to drive away dolphins.

[0079] See Figure 2 The initial high-speed boat noise HSN0 is the initially generated noise; the subscript 0 indicates "initial." The high-speed boat noise replica signal HSN... i-1 This refers to the signal stored in a temporary register after being frequency-shifted by the amplitude-shifting frequency shifter. For example, after frequency-shifting, HSN0 becomes HSN1, which is then stored in the temporary register as a copy for future use. In the next round of transmission, the copy of HSN1 is frequency-shifted to obtain HSN2, which is also stored in the temporary register as a copy for future use. This process continues in sequence, and the copy of HSN is updated with each subsequent transmission. i-1 Signal.

[0080] High-speed boat noise copy HSN i-1 The HSN is obtained after frequency offset processing of the amplitude-shifting frequency shifter H(ω;t) designed in step 6. i Store in temporary register to update HSN i-1 Copy, and simultaneously HSN i It is superimposed with the sweep frequency signal LFM1, and then the amplitude is adjusted by the amplitude shifter H(ω;t). Finally, it is emitted through the cylindrical underwater acoustic transducer to drive away dolphins with sound.

[0081] The overall processing of the amplitude frequency shifter H(ω;t) is as follows: Figure 6 As shown, let the noise replica of the high-speed boat be HSN. i-1 The signal is x(t), and the high-speed boat noise signal output after frequency conversion is HSN. i The frequency conversion process involves the input signal x(t) undergoing a Hilbert transform followed by IQ modulation. Let the generated down-sweep signal LFM1 be z(t), and let z(t) be related to the high-speed boat noise signal HSN. i After superposition, amplitude adjustment is performed to finally obtain the output signal y(t) processed by the amplitude frequency shifter H(ω;t). Figure 6 The overall process is the processing of the amplitude-frequency shifter, and its formula can be expressed as:

[0082]

[0083] Wherein, H[·] is a Hilbert transform symbol, and Ai and Δfi are calculated through an amplitude adjustment coefficient k and a frequency shift adjustment coefficient r. τ is an integral operator in the calculation process.

[0084] The feedback adjustment of steps 2 to 8 is continuously repeated, and the process of continuously emitting the dolphin sound drive sound wave also changes the amplitude and frequency of the dolphin sound drive sound wave with the feedback adjustment process. When the sound wave emission has been performed for a length T that reaches the target length T of the sound drive activity max , the sound wave emission is stopped, and the current dolphin sound drive activity is ended.

[0085] Figure 7 is a schematic diagram of the number of click signals emitted by dolphins in the region after the dolphins are sound driven by the method of the present application. The click signals of the dolphins can represent the number of dolphins in the region. From Figure 7 it can be seen that the number of click signals emitted by dolphins in the region decreases significantly from 956 times per minute to 86 times per minute, indicating that the method of the present application can effectively drive dolphins for a long time, achieving the purpose of protecting dolphins from being harmed in underwater engineering activities.

[0086] Based on the method provided by the present application, the present application also provides a dolphin sound drive system based on underwater acoustic signal feedback adjustment, comprising:

[0087] a signal generation module, configured to generate a downward frequency signal according to the frequency range of the dolphin hearing threshold, and generate an initial high-speed yacht noise signal according to the hearing threshold curve of the dolphin;

[0088] a signal superposition and emission module, configured to superimpose the downward frequency signal and the initial high-speed yacht noise signal, and emit the superimposed signal through a cylindrical underwater acoustic transducer for driving dolphins;

[0089] a signal receiving and calculating module, configured to receive ocean ambient noise through a spherical receiving hydrophone and calculate the frequency band sound pressure level of the ocean ambient noise;

[0090] an amplitude adjustment coefficient calculation module, configured to calculate the amplitude adjustment coefficient of the superimposed signal according to the frequency band sound pressure level of the ocean ambient noise;

[0091] a frequency shift adjustment coefficient calculation module, configured to calculate the frequency shift adjustment coefficient of the high-speed yacht noise signal according to the length of time for which the superimposed signal has been emitted;

[0092] a variable amplitude frequency shifter updating module, configured to feedback adjust and update the variable amplitude frequency shifter designed based on Hilbert transform according to the amplitude adjustment coefficient and the frequency shift adjustment coefficient;

[0093] The superimposed signal feedback adjustment module is configured to obtain a new superimposed signal through frequency shift processing and amplitude adjustment by using a variable amplitude frequency shifter, and return the superimposed signal to the step of emitting the superimposed signal through the cylindrical underwater acoustic transducer to drive away dolphins.

[0094] Further, the present application also provides an electronic device, which can include a processor, a communication interface, a memory and a communication bus. Wherein, the processor, the communication interface and the memory complete mutual communication through the communication bus. The processor can call the computer program in the memory to execute the dolphin sound driving method based on the feedback adjustment of underwater acoustic signals.

[0095] In addition, the computer program in the memory described above is implemented in the form of a software functional unit and sold or used as an independent product, which can be stored in a non-transitory computer readable storage medium. Based on such understanding, the technical solutions of the present application or the part of the technical solutions that make essential contributions to the prior art can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a plurality of instructions to make a computer device (which can be a personal computer, a server or a network device, etc.) execute all or part of the steps of the method described in various embodiments of the present application. The foregoing storage medium includes a U disk, a mobile hard disk, a read-only memory, a random access memory, a magnetic disk or an optical disk, and various media that can store program codes.

[0096] In the method of the present application, the superposition of the sweep frequency signal and the high-speed ship noise signal is used as the artificial synthetic sound wave for sound driving. The frequency range of the sweep frequency signal and the frequency components of the high-speed ship noise are selected according to the threshold curve characteristics of the dolphins, so that the dolphins are more sensitive to the sound wave and the ship noise has a deterrent effect on the dolphins, which can effectively improve the success rate of dolphin sound driving. Further, in order to avoid the situation that the dolphin sound driving effect significantly decreases or disappears over time under continuous sound wave stimulation (because dolphins are adaptive to sound), the feedback adjustment mechanism (including frequency shift adjustment according to the time T of sound wave emission and feedback adjustment of the amplitude of the emitted sound wave according to the frequency band sound pressure level of the marine environment noise) for the emitted sound wave is added in the method of the present application to simulate the frequency shift and amplitude change of the real ship noise propagation, so as to maintain the variability of the frequency and amplitude of the emitted sound wave, thereby effectively driving the dolphins for a long time, and achieving the purpose of protecting the dolphins from being harmed in underwater engineering activities.

[0097] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other. For the system disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method part.

[0098] The principles and implementations of the present application are described in the specific examples herein, and the above examples are only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in specific implementation and application range. In view of the above, the content of the specification should not be understood as a limitation of the present application.

Claims

1. A dolphin sound repelling method based on feedback adjustment of underwater acoustic signals, characterized in that, The method comprises the following steps: generating a downward frequency signal according to the frequency range of the dolphin hearing threshold, and generating an initial high-speed yacht noise signal according to the hearing threshold curve of the dolphin; superimposing the downward frequency signal and the initial high-speed yacht noise signal, and emitting the superimposed signal through a cylindrical underwater acoustic transducer for driving away dolphins; receiving ocean ambient noise through a spherical receiving hydrophone and calculating the frequency band sound pressure level of the ocean ambient noise; The calculation of the frequency band sound pressure level of the ocean ambient noise specifically comprises: The formula is used to calculate the band sound pressure level of the ocean ambient noise ; wherein is the sound pressure value of the sound wave of the ocean ambient noise in the bandwidth; is the reference sound pressure; calculating the amplitude adjustment coefficient of the superimposed signal according to the frequency band sound pressure level of the ocean ambient noise, specifically comprising: Based on the frequency band sound pressure level of marine environmental noise Using formula Calculate the amplitude adjustment coefficient of the superimposed signal k ;in This is the maximum voltage value that the cylindrical underwater acoustic transducer can receive. calculating the frequency shift adjustment coefficient of the high-speed yacht noise signal according to the duration of the emission of the superimposed signal, specifically comprising: The time duration of the superimposed signal transmission has been carried out T , the formula is used to calculate the frequency shift adjustment coefficient of the high-speed yacht noise signal r ; wherein is the target time duration of the superimposed signal transmission; feedback adjustment and updating of the variable amplitude frequency shifter based on Hilbert transform design according to the amplitude adjustment coefficient and the frequency shift adjustment coefficient, specifically comprising: According to the amplitude adjustment coefficient k Using formula Calculate the first i Amplitude adjustment coefficient of superimposed signal in round feedback regulation ;in The maximum amplitude of the superimposed signal is set. According to the frequency shift adjustment coefficient r , the formula is used to calculate the i frequency shift amount of the high-speed yacht noise signal in the first feedback adjustment ; wherein is the maximum frequency shift of the high-speed yacht noise signal in the first feedback adjustment According to the amplitude adjustment coefficient and frequency shift To update the amplitude-shifting frequency converter based on Hilbert transform design ;in For Hilbert transforms; x ( t The noise signal of the high-speed boat is input to the frequency shifter. z ( t () is the downsweep signal input to the amplitude shifter; y ( t The signal is the superimposed signal output from the amplitude-frequency shifter. After frequency shift processing and amplitude adjustment by the variable amplitude frequency shifter, a new superimposed signal is obtained, and the step of emitting the superimposed signal through the cylindrical underwater acoustic transducer for driving away dolphins is returned.

2. A dolphin sound repelling system based on feedback adjustment of underwater acoustic signals, characterized in that, The method comprises the following steps: a signal generation module for generating a downward frequency signal according to the frequency range of the dolphin hearing threshold, and generating an initial high-speed yacht noise signal according to the hearing threshold curve of the dolphin; a signal superposition and emission module for superimposing the downward frequency signal and the initial high-speed yacht noise signal, and emitting the superimposed signal through a cylindrical underwater acoustic transducer for driving away dolphins; a signal receiving and calculating module for receiving ocean ambient noise through a spherical receiving hydrophone and calculating the frequency band sound pressure level of the ocean ambient noise; The calculation of the frequency band sound pressure level of the ocean ambient noise specifically comprises: The formula is used to calculate the band sound pressure level of the ocean ambient noise ; wherein is the sound pressure value of the sound wave of the ocean ambient noise in the bandwidth; is the reference sound pressure; an amplitude adjustment coefficient calculation module for calculating the amplitude adjustment coefficient of the superimposed signal according to the frequency band sound pressure level of the ocean ambient noise, specifically comprising: Based on the frequency band sound pressure level of marine environmental noise Using formula Calculate the amplitude adjustment coefficient of the superimposed signal k ;in This is the maximum voltage value that the cylindrical underwater acoustic transducer can receive. a frequency shift adjustment coefficient calculation module for calculating the frequency shift adjustment coefficient of the high-speed yacht noise signal according to the duration of the emission of the superimposed signal, specifically comprising: The time duration of the superimposed signal transmission has been carried out T , the formula is used to calculate the frequency shift adjustment coefficient of the high-speed yacht noise signal r ; wherein is the target time duration of the superimposed signal transmission; a variable amplitude frequency shifter updating module for feedback adjustment and updating of the variable amplitude frequency shifter based on Hilbert transform design according to the amplitude adjustment coefficient and the frequency shift adjustment coefficient, specifically comprising: According to the amplitude adjustment coefficient k Using formula Calculate the first i Amplitude adjustment coefficient of superimposed signal in round feedback regulation ;in The maximum amplitude of the superimposed signal is set. According to the frequency shift adjustment coefficient r Using formula Calculate the first i Frequency shift of noise signal in high-speed boat during wheel feedback regulation ;in The maximum frequency shift of the high-speed boat noise signal during a single feedback adjustment is set. Updating a variable amplitude frequency shifter designed based on a hilbert transform according to an amplitude adjustment coefficient and a frequency shift amount ; wherein H is a hilbert transform operator; ; x ( t ) is a high speed boat noise signal input to the variable amplitude frequency shifter; z ( t ) is a down chirp signal input to the variable amplitude frequency shifter; y ( t ) is a superimposed signal output from the variable amplitude frequency shifter; a superimposed signal feedback adjustment module for obtaining a new superimposed signal after frequency shift processing and amplitude adjustment by the variable amplitude frequency shifter, and returning to the step of emitting the superimposed signal through the cylindrical underwater acoustic transducer for driving away dolphins.

3. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to realize the dolphin sound driving method based on underwater acoustic signal feedback adjustment as claimed in claim 1.

4. The electronic device of claim 3, wherein, The memory is a non-transitory computer readable storage medium.

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