Interference system and recording shielding equipment

Abstract

The invention discloses an interference system and recording shielding equipment, and aims to solve the problems that harsh noise is generated during recording shielding in the prior art, and the use experience of a user is affected. Wherein the ultrasonic transmitting module is used for transmitting ultrasonic waves; the frequencies of ultrasonic waves transmitted by different ultrasonic wave transmitting modules are different; the absolute value of the frequency difference of the ultrasonic waves of any two ultrasonic transmitting modules is smaller than the frequency of the ultrasonic waves transmitted by any one ultrasonic transmitting module; i > = 2. Difference frequency signals generated in the propagation process of the ultrasonic waves with different frequencies in the air can be propagated to the sound receiving position of the sound recording equipment to be recorded and then generate interference on recorded sound signals, so that the aim of preventing sound recording is fulfilled; the absolute value of the frequency difference of any two ultrasonic waves is smaller than the frequency of any one ultrasonic wave, so that the ultrasonic waves are not easily perceived by human ears, the use experience safety of a user is improved, and the applicability is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic equipment, and in particular to an interference system and recording shielding equipment. Background Art

[0002] With the development of science and technology, more and more people are concerned about information security issues such as privacy leakage. In some occasions where voice information needs to be kept confidential, operations such as recording shielding are required to prevent relevant personnel from eavesdropping on private information by recording.

[0003] There are three main recording shielding technologies at present, which are based on electromagnetic wave technology, white noise technology and ultrasonic technology to achieve recording shielding. Among them, electromagnetic wave technology mainly achieves recording shielding function by interfering with the sampling circuit of the microphone, but with the emphasis on electromagnetic compatibility (EMC) testing of electronic products, the shielding effect of electromagnetic wave technology has been difficult to meet the shielding requirements; white noise technology refers to the generation of white noise audible to the human ear in the environment to interfere with the recording shielding equipment. Its main purpose is to increase the background noise of the environment, but the use of this technology will have a certain impact on the normal communication between users.

[0004] In view of this, how to provide an interference system and a recording shielding device that can both achieve recording shielding and improve user experience has become a problem that technical personnel in this field need to solve. Summary of the invention

[0005] The purpose of the embodiments of the present invention is to provide a jamming system and a recording shielding device, which can improve the user experience while achieving recording shielding and is not easily detected by eavesdroppers.

[0006] To solve the above technical problems, the embodiments of the present invention provide the following technical solutions:

[0007] A first aspect of an embodiment of the present invention provides an interference system, comprising i ultrasonic transmitting modules; wherein:

[0008] The ultrasonic transmitting module is used to transmit ultrasonic waves; the frequencies of ultrasonic waves transmitted by different types of ultrasonic transmitting modules are different; the absolute value of the frequency difference of ultrasonic waves transmitted by any two types of ultrasonic transmitting modules is smaller than the frequency of ultrasonic waves transmitted by any type of ultrasonic transmitting modules; i≥2.

[0009] In one embodiment, the frequency difference ranges from 150 Hz to 200 Hz.

[0010] In one embodiment, the frequencies of the ultrasonic waves of the various ultrasonic transmitting modules can be sorted in a preset order, and the absolute value of the frequency difference between any two adjacent frequencies of the ultrasonic waves after sorting is the same.

[0011] In one embodiment, the frequency range of the ultrasonic wave emitted by the ultrasonic wave transmitting module is 25KHz~40KHz.

[0012] In one embodiment, there are 4 to 6 types of ultrasonic emission modules.

[0013] In one embodiment, the ultrasonic transmitting module includes:

[0014] A signal source, used for transmitting a frequency signal;

[0015] at least one driving circuit connected to the signal source, configured to generate a driving signal based on the frequency signal;

[0016] Each of the driving circuits is connected to at least one ultrasonic probe, and the ultrasonic probe is used to transmit ultrasonic waves of corresponding frequencies based on the driving signal.

[0017] In one embodiment, there is one driving circuit in the ultrasonic transmitting module, and there are multiple ultrasonic probes connected to the driving circuit.

[0018] In one embodiment, there are multiple driving circuits and ultrasonic probes in the ultrasonic transmitting module, and there is one ultrasonic probe connected to each driving circuit.

[0019] In one embodiment, the ultrasonic transmitting module includes two or more ultrasonic probes of the same frequency; the ultrasonic probes of the same frequency are arranged along the direction of gravity.

[0020] In one embodiment, all ultrasonic probes in multiple types of ultrasonic transmitting modules are arranged in the form of n rows and m columns, and the ultrasonic probes in the same type of ultrasonic transmitting module are arranged in sequence along the direction of gravity; wherein n represents the number of ultrasonic probes in one type of ultrasonic transmitting module, and m represents the type of the ultrasonic transmitting module.

[0021] In one embodiment, the frequencies of the ultrasonic probes in different columns decrease or increase successively along the arrangement direction of the columns, wherein the arrangement direction is parallel to the direction from one end to the other end of any row.

[0022] In one embodiment, i≥4, each of the ultrasonic emission modules includes one or more ultrasonic probes with the same frequency; the interference system includes one or more probe sets, each of the probe sets includes i ultrasonic probes with different frequencies;

[0023] In one of the probe sets, the ultrasonic probes are arranged in a pattern of z rows and k columns, wherein z represents the number of rows, and z≥2; and k represents the number of columns, and k≥2.

[0024] In one embodiment, i is 4, and all the ultrasonic probes in each probe set are arranged in the form of 2 rows and 2 columns.

[0025] In one embodiment, there are multiple probe sets, and the multiple probe sets are arranged in sequence along the first direction or the second direction, and the first direction and the second direction are perpendicular to each other.

[0026] A second aspect of an embodiment of the present invention further provides a recording shielding device including the interference system as described above.

[0027] The third aspect of the embodiments of the present invention also provides a recording shielding device, which includes a mounting body, and at least one of the above-mentioned interference systems is provided on at least one side wall of the mounting body; the interference system includes a plurality of ultrasonic transmitting modules, each of the ultrasonic transmitting modules includes one or more ultrasonic probes with the same frequency; the ultrasonic probes of different frequencies in the interference system are arranged in sequence along the horizontal direction.

[0028] A fourth aspect of the embodiments of the present invention further provides a recording shielding device, comprising the above-mentioned interference system, wherein the recording shielding device further comprises a box body, wherein a receiving cavity for carrying the device to be interfered is formed inside the box body; each of the ultrasonic transmitting modules comprises one or more ultrasonic probes with the same frequency;

[0029] The ultrasonic probe is arranged between the outer wall of the box body and the accommodating cavity.

[0030] It can be seen from the above technical solutions that the embodiments of the present invention have the following advantages:

[0031] In an embodiment of the present invention, an interference system is provided, comprising i types of ultrasonic emission modules, i≥2. The ultrasonic emission modules are used to emit ultrasonic waves. The frequencies of ultrasonic waves emitted by different types of ultrasonic emission modules are different. The absolute value of the frequency difference of ultrasonic waves of any two ultrasonic emission modules is less than the frequency of ultrasonic waves emitted by any one ultrasonic emission module.

[0032] In the interference system and recording shielding device provided in the embodiment of the present application, the ultrasonic frequencies emitted by the i types of ultrasonic emission modules are all different, and the ultrasonic waves of different frequencies will have a mixing effect during the propagation in the air, thereby generating a difference frequency signal, a sum frequency signal and a second harmonic signal. According to the principle of sound absorption, the frequencies of the original signal, the sum frequency signal and the second harmonic signal are all relatively high and are easily absorbed by the air, while the difference frequency signal can be propagated to the sound receiving place (such as the microphone) of the recording device due to its low frequency. At this time, if the recording device is in an illegal recording state, the difference frequency signal and the audio signal originally to be recorded will be recorded together, and the audio finally presented will be distorted, noisy or otherwise unable to be listened to normally, thereby achieving the purpose of preventing being recorded. Since ultrasonic waves cannot be heard by the human ear, the embodiment of the present application uses ultrasonic waves for recording shielding, which can reduce the impact on the human ear and improve the user experience.

[0033] In addition, the present invention also provides a corresponding recording shielding device for the interference system, which further makes the method more practical, and the recording shielding device has corresponding advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A schematic diagram of a module of an interference system provided by an embodiment of the present invention;

[0036] Figure 2 For Figure 1 Schematic diagram of the second-order harmonics generated by the nonlinear effects of the corresponding two ultrasonic waves;

[0037] Figure 3 A schematic diagram of another module of an interference system provided by an embodiment of the present invention;

[0038] Figure 4 A specific schematic diagram of another interference system provided by an embodiment of the present invention;

[0039] Figure 5 A jamming system provided by an embodiment of the present invention includes a schematic diagram of 4 ultrasonic transmitting modules;

[0040] Figure 6 An ultrasonic module provided by an embodiment of the present invention includes a circuit diagram of a plurality of ultrasonic probes;

[0041] Figure 7Another ultrasonic module provided by an embodiment of the present invention includes a circuit diagram of a plurality of ultrasonic probes;

[0042] Figure 8 A schematic diagram of the arrangement of ultrasonic probes of an interference system provided by an embodiment of the present invention;

[0043] Fig. 9 A schematic diagram of the arrangement of an ultrasonic probe array for use in a long-distance scene provided by an embodiment of the present invention;

[0044] Fig.10 A method provided by an embodiment of the present invention Fig. 9 Corresponding probe arrangement scheme and single probe scheme beam comparison diagram;

[0045] Fig.11 A method provided by an embodiment of the present invention Fig. 9 Comparison diagram of the corresponding probe arrangement scheme and radiation direction of a single probe scheme;

[0046] Fig.12 A schematic structural diagram of a recording shielding device provided by an embodiment of the present invention;

[0047] Fig.13 A schematic diagram of another arrangement of ultrasonic probes provided in an embodiment of the present invention;

[0048] Fig.14 A schematic structural diagram of another recording shielding device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] In order to solve the problems existing in the traditional recording shielding technology, the present invention provides a jamming system. Figure 1 , 3 , is a schematic diagram of modules of two interference systems provided by an embodiment of the present invention. The interference system includes i types of ultrasonic emission modules. Among them:

[0051] The ultrasonic transmitting module is used to transmit ultrasonic waves. The frequencies of ultrasonic waves transmitted by different ultrasonic transmitting modules are different. The absolute value of the frequency difference of ultrasonic waves of any two ultrasonic transmitting modules is less than the frequency of ultrasonic waves transmitted by any one ultrasonic transmitting module, i≥2.

[0052] First, the working principle of the jamming system provided in the embodiment of the present application is described. Figure 1 and Figure 2 , take the interference system including two ultrasonic emission modules as an example, such as the interference system including ultrasonic emission module 1A and ultrasonic emission module 1B, the frequency of ultrasonic emission module 1A emits ultrasonic waves of f1, and the frequency of ultrasonic emission module 1B emits ultrasonic waves of f2. After ultrasonic emission module 1A and ultrasonic emission module 1B emit ultrasonic waves, due to the nonlinear acoustic effect of the medium, under the condition of only considering the second-order quantity (such as Figure 2 As shown in the figure), the difference frequency signal f2-f1, the sum frequency signal f1+f2, the original signal f1, the original signal f2 and the second harmonic signals 2f1 and 2f2 of the original signal will be obtained. According to the principle of sound absorption, the absorption intensity of air is proportional to the square of the sound wave frequency. The higher the frequency, the easier it is to be absorbed by air. Therefore, the sum frequency signal f1+f2, the original signal f1, the original signal f2 and the second harmonic signals 2f1 and 2f2 will decay quickly, and the remaining signal is mainly the difference frequency signal f2-f1. Therefore, when the difference frequency signal f2-f1 reaches the sound receiving part (such as a microphone) of the recording device, the difference frequency signal f2-f1 will be recorded by the microphone together with the recorded sound signal. The difference frequency signal f2-f1 will interfere with the recorded sound signal, causing the sound played through the recording device to be distorted, noisy or otherwise unable to be listened to normally, thereby achieving the purpose of preventing recording, so that the user can use the interference system to achieve the purpose of anti-eavesdropping.

[0053] Further, in some embodiments of the present invention, Figure 3As shown, the i-type (i≥2) ultrasonic transmitting modules of the interference system can be ultrasonic transmitting module 1A, ultrasonic transmitting module 1B, ..., ultrasonic transmitting module 1i. The ultrasonic frequency emitted by each ultrasonic transmitting module is different. For example, the ultrasonic frequency emitted by ultrasonic transmitting module 1A is f1, the ultrasonic frequency emitted by ultrasonic transmitting module 1B is f2, ..., and the ultrasonic frequency emitted by ultrasonic transmitting module 1i is fi. When ultrasonic waves of different frequencies propagate in the air, a mixing effect will occur. A difference frequency signal and a sum frequency signal will be generated between any two ultrasonic signals of different frequencies. Each original signal will generate a second harmonic signal respectively. According to the principle of sound absorption, the original signal, the second harmonic signal of the original signal, and the sum frequency signal have higher frequencies and are more easily absorbed by the air, while the difference frequency signal has a lower frequency and is not easily absorbed by the air. It has a longer propagation distance and can be propagated to the sound receiving point of the recording device. If the recording device is in an illegal recording state, the difference frequency signal will be recorded together with the recorded sound signal, and the difference frequency signal will interfere with the recorded sound signal, causing the recorded sound signal to be unable to be played normally, thereby achieving the purpose of preventing it from being recorded. Since ultrasound cannot be heard by the human ear, the embodiment of the present application uses ultrasound for recording shielding, which can reduce the impact on the human ear and improve the user experience.

[0054] It should also be noted that the absolute value of the frequency difference between the ultrasonic waves emitted by any two ultrasonic emission modules is less than the frequency of the ultrasonic wave emitted by any one ultrasonic emission module. In other words, the frequency of the ultrasonic wave is relatively large, while the frequency difference between ultrasonic waves of different frequencies (that is, the frequency of the difference frequency signal) is relatively low, that is, the embodiment of the present application adopts a plurality of ultrasonic waves with relatively small frequency differences to perform recording shielding. Moreover, since the frequency of the difference frequency signal is relatively low, the difference frequency signal is closer to the recorded signal, that is, the frequency range of the difference frequency signal is within the receiving range of the recording device, and is more easily interfered by the recording signal.

[0055] In one embodiment, the frequency difference ranges from 150 Hz to 200 Hz.

[0056] It should be noted that the sound frequency range that the human ear can hear is 20 Hz ~20000 Hz, and according to experimental research, the human ear is most sensitive to sound waves between 1000 Hz ~3000 Hz.

[0057] Based on this, in the embodiment of the present invention, it is considered that the human ear is not sensitive to the sound of 150HZ-200Hz (i.e., far less than the above-mentioned 1000Hz ~ 3000Hz), so when the interference signal with a frequency difference of 150HZ-200Hz (i.e., an embodiment of the above-mentioned difference frequency signal) is used for recording shielding, the noise generated is not easily detected by the eavesdropper. Therefore, the frequency of the ultrasonic wave emitted by each ultrasonic wave transmitting module can be set so that the frequency difference of the ultrasonic wave emitted by any two ultrasonic wave modules is within the range of 150Hz~200Hz, so as to achieve interference to the eavesdropper while more effectively reducing the impact of noise on the user, further improving the user experience, reducing the possibility of noise being detected by the eavesdropper, and further improving security.

[0058] For example, in the embodiment of the present invention, the frequency difference of the ultrasonic waves of any two ultrasonic transmitting modules can be 150 Hz, 160 Hz, 170 Hz, 180 Hz, 190 Hz, or 200 Hz. Of course, it can also be other specific values. The specific value of the frequency difference can be determined according to actual needs, as long as it is within the frequency range that is not easily heard by the human ear.

[0059] In one embodiment, the frequencies of the ultrasonic waves of various ultrasonic transmitting modules can be sorted in a preset order, and the absolute value of the frequency difference between the frequencies of any two adjacent ultrasonic waves after the sorting is the same.

[0060] It is understandable that the frequencies of the ultrasonic waves of the various ultrasonic emission modules in the interference system in the embodiment of the present invention can be sorted in a preset order, for example, the frequencies of the ultrasonic waves of the various ultrasonic emission modules gradually increase or decrease with the same frequency difference, so that the absolute value of the frequency difference between any two adjacent ultrasonic waves is the same. In other words, when selecting ultrasonic emission modules in the embodiment of the present invention, various ultrasonic emission modules whose frequencies increase or decrease in sequence are selected respectively. It should be noted that the sorting mentioned here is only to illustrate the size relationship between the ultrasonic frequencies of different types of ultrasonic emission modules, and does not mean that the sorting action needs to be performed.

[0061] Since the absolute value of the frequency difference between any two adjacent ultrasonic waves after sorting is the same, there will be multiple difference frequency signals with the same frequency at the same time. The superposition of multiple difference frequency signals with the same frequency can generate a stronger interference signal, thereby more effectively interfering with the recorded sound signal and further improving the anti-recording effect.

[0062] like Figure 5The interference system shown includes four ultrasonic emission modules, and the frequencies of the ultrasonic waves emitted by the four ultrasonic emission modules are f1, f2, f3, and f4, respectively. These four ultrasonic frequencies can be sorted from low to high or from high to low according to size. That is to say, the absolute value of the difference between f1 and f2, the absolute value of the difference between f2 and f3, and the absolute value of the difference between f3 and f4 are all the same. In the embodiment of the present invention, it is assumed that f1 to f4 increase in sequence, then f2-f1=f3-f2=f4-f3, therefore, the difference frequency signals f2-f1, f3-f2, and f4-f3 with the same frequency are superimposed on each other to form a stronger interference signal, which can produce a stronger interference effect on the recorded sound signal after being recorded by the recording device. Of course, these four ultrasonic emission modules can also generate other difference frequency signals, such as f3-f1, f4-f2, and f4-f1, and these difference frequency signals also have a certain interference effect.

[0063] In one embodiment, the frequency range of the ultrasonic wave emitted by the ultrasonic wave transmitting module is 25KHz~40KHz.

[0064] It should be noted that, since the ultrasonic frequency is too high, it will decay quickly in the air and cannot achieve anti-interference, and the ultrasonic frequency is too low, the noise will be large. Therefore, the frequency range of the ultrasonic wave emitted by the ultrasonic emission module in the embodiment of the present invention can be 25KHz~40KHz. Within this range, the ultrasonic frequency will not fail to meet the interference requirements (or recording shielding requirements) due to the excessively high frequency causing the ultrasonic signal to decay too quickly in the air, nor will it cause excessive noise due to the low frequency of the ultrasonic wave, affecting the user experience. In actual applications, the frequency of the ultrasonic wave emitted by the ultrasonic emission module can be 25KHz, 26KHz, 27KHz, 28KHz, 29KHz, 30KHz, 31KHz, 32KHz, 33KHz, 34KHz, 35KHz, 40KHz, etc. Of course, the specific value of the preset frequency setting can be determined according to actual needs, as long as it is within this range.

[0065] If 36KHz is assumed to be the ultrasonic frequency of one of the ultrasonic emission modules, and there are 4 ultrasonic emission modules in total, and the frequencies of the 4 ultrasonic emission modules increase in sequence with the same frequency difference (such as 150Hz), then after the 4 ultrasonic waves are emitted, f1=36KHz, f2=36.15KHz, f3=36.3KHz, and f4=36.45KHz. In this way, after the 4 ultrasonic waves are emitted, a 150Hz difference frequency signal will be generated between 36KHz and 36.15KHz, between 36.15KHz and 36.3KHz, and between 36.3KHz and 36.45KHz, so the 150Hz difference frequency signal will have a stronger recording shielding effect.

[0066] In one embodiment, there are 4 to 6 types of ultrasonic emission modules.

[0067] In the embodiment of the present invention, it is considered that if there are fewer types of ultrasonic emission modules, the number of difference frequency signals will be reduced, resulting in a weaker intensity of the interference signal, and the effect of interference or recording shielding cannot be achieved. In addition, if there are more types of ultrasonic emission modules, the effect of interference or recording shielding will not be significantly increased, but the complexity of the control circuit setting and the overall cost will increase. Therefore, the types of ultrasonic emission modules in the embodiment of the present invention can be 4 to 6. That is, four ultrasonic emission modules, five ultrasonic emission modules, or six ultrasonic emission modules can be used in the interference system, which can achieve the purpose of interference or recording shielding without increasing the complexity of the circuit design and saving costs.

[0068] In one embodiment, the sound pressure level of the ultrasonic waves of various ultrasonic transmitting modules is greater than a preset sound pressure level, so that the sound pressure level of the difference frequency signal that can be formed between the frequencies of the ultrasonic waves of any two ultrasonic transmitting modules is greater than the maximum sound pressure level (AOP, Acoustic Overload Point) of the microphone in the recording device, thereby making it easier for the microphone to be distorted, which can further improve the anti-recording effect.

[0069] In one embodiment, the ultrasonic transmitting module includes:

[0070] The signal source 11 is used for transmitting a frequency signal.

[0071] At least one driving circuit 12 connected to the signal source 11 is used to generate a driving signal based on the frequency signal.

[0072] Each driving circuit 12 is connected to at least one ultrasonic probe 13 , and the ultrasonic probe 13 is used to transmit ultrasonic waves of corresponding frequencies based on a driving signal.

[0073] It should be noted that the ultrasonic transmitting module in the embodiment of the present invention includes a signal source 11, at least one driving circuit 12 connected to the signal source 11, and at least one ultrasonic probe 13 connected to the driving circuit 12. The frequency signal emitted by the signal source 11 is transmitted to the driving circuit 12, and the driving circuit 12 generates a corresponding driving signal according to the frequency signal, and uses the driving signal to drive the corresponding ultrasonic probe 13 to emit an ultrasonic wave of the corresponding frequency, so that the ultrasonic transmitting module emits an ultrasonic wave of the corresponding frequency. Among them, the signal source 11 may include a signal generator such as a processor or an oscillator, which is not limited here. The frequency signal is, for example, a sinusoidal signal pulse signal or other signal with a specific frequency, and the frequency of the frequency signal can be set according to actual needs, which is not limited here. For example, the frequency of the frequency signal can be greater than or equal to 25KHz and less than or equal to 40KHz. The signal source of the driving circuit 12 is used, for example, to amplify the frequency signal to generate a driving signal. The driving circuit 12 includes, for example, a power amplifier and peripheral circuits to achieve power amplification.

[0074] Since the interference system includes a variety of ultrasonic transmitting modules that transmit different frequencies, the signal sources 11 in different types of ultrasonic transmitting modules transmit different frequency signals, so that the corresponding ultrasonic probes 13 transmit ultrasonic waves of different frequencies.

[0075] In one embodiment, the ultrasonic transmitting module includes a driving circuit 12 and an ultrasonic probe 13 connected to the driving circuit 12 .

[0076] For example, see Figure 4 The interference system includes an ultrasonic transmitting module 1A and an ultrasonic transmitting module 1B. The ultrasonic transmitting module 1A includes a signal source 11A, a driving circuit 12A connected to the signal source 11A, and an ultrasonic probe 13A connected to the driving circuit. The ultrasonic transmitting module 1B includes a signal source 11B, a driving circuit 12B connected to the signal source 11B, and an ultrasonic probe 13B connected to the driving circuit. The signal source (11A, 11B) sends a frequency signal, and the driving circuit (12A, 12B) generates a driving signal according to the frequency signal to drive the ultrasonic probe 13A and the ultrasonic probe 13B to generate ultrasonic waves with frequencies f1 and f2 respectively, and the absolute value of the frequency difference between f1 and f2 is less than the frequency of any one of the ultrasonic waves (that is, any one of f1 and f2). In this embodiment, the difference frequency signal is mainly f2-f1.

[0077] For example, see Figure 5, the interference system includes four types of ultrasonic transmitting modules, namely ultrasonic transmitting module 1A, ultrasonic transmitting module 1B, ultrasonic transmitting module 1C and ultrasonic transmitting module 1D. Ultrasonic transmitting module 1A includes a signal source 11A, a driving circuit 12A, and an ultrasonic probe 13A. Among them, the signal source 11A sends a frequency signal 1, and the driving circuit 12A generates a driving signal 1 according to the frequency signal 1 to drive the ultrasonic probe 13A to generate an ultrasonic wave with a frequency of f1. The ultrasonic transmitting module 1B includes a signal source 11B, a driving circuit 12B, and an ultrasonic probe 13B, wherein the signal source 11B sends a frequency signal 2, and the driving circuit 12B generates a driving signal 2 according to the frequency signal 2 to drive the ultrasonic probe 13B to generate an ultrasonic wave with a frequency of f2. The ultrasonic transmitting module 1C includes a signal source 11C, a driving circuit 12C, and an ultrasonic probe 13C, wherein the signal source 11C sends a frequency signal 3, and the driving circuit 12C generates a driving signal 3 according to the frequency signal 3 to drive the ultrasonic probe 13C to generate an ultrasonic wave with a frequency of f3. The ultrasonic transmitting module 1D includes a signal source 11D, a driving circuit 12D, and an ultrasonic probe 13D, wherein the signal source 11D sends a frequency signal 4, and the driving circuit 12D generates a driving signal 4 according to the frequency signal 4 to drive the ultrasonic probe 13D to generate ultrasonic waves with a frequency of f4.

[0078] It should be noted that the frequency difference between any two frequencies of f1, f2, f3, and f4 in the embodiment of the present invention is in the range of 150Hz~200Hz, and the frequency ranges of f1, f2, f3, and f4 are all 25KHz~40KHz. And the frequencies of the ultrasonic waves of the above four ultrasonic emission modules can be sorted in order according to size, and the absolute value of the frequency difference between any two adjacent ultrasonic frequencies after sorting is the same. For example, the frequencies of the ultrasonic waves emitted by each ultrasonic probe are f1=36KHz, f2=36.15KHz, f3=36.3KHz, and f4=36.45KHz, respectively. After the ultrasonic waves emitted by these ultrasonic probes produce a mixing effect in the air, a 150Hz difference frequency signal can be formed between any two adjacent frequencies, that is, a 150Hz difference frequency signal will be generated between 36KHz and 36.15KHz, between 36.15KHz and 36.3KHz, and between 36.3KHz and 36.45KHz. Moreover, the ultrasonic emission frequencies of the four ultrasonic emission modules differ by 150Hz respectively. The difference frequency (150Hz) in the embodiment of the present invention is much smaller than the frequency of each ultrasonic wave (ie: 36KHz, 36.15KHz, 36.3KHz, 36.45KHz). The difference frequency signals with the same frequency are superimposed on each other, and finally form a strong interference signal, which can better interfere with the recorded sound signal after being recorded by the recording equipment, so as to achieve better interference or recording shielding effect. In addition, it should be noted that the other difference frequency signals (f3-f1, f4-f2, f4-f1) can also achieve a certain interference effect. Since the number of difference frequency signals with a frequency of 150HZ is the largest, the interference effect of this difference frequency signal is the strongest.

[0079] In one embodiment, if Figure 6 As shown, there may be one driving circuit 12 in the ultrasonic transmitting module, and there may be multiple ultrasonic probes 13 connected to the driving circuit 12.

[0080] It is understandable that any one of the ultrasonic transmitting modules in the interference system of the embodiment of the present invention may be provided with a driving circuit 12 and a plurality of ultrasonic probes 13 (such as Figure 6As shown in the figure, there are four ultrasonic probes 13 connected to one driving circuit 12, so that multiple ultrasonic probes 13 can emit ultrasonic waves of the same frequency. After multiple ultrasonic waves with the same frequency are emitted, multiple difference frequency signals of the same number can be generated with ultrasonic waves of other frequencies. Multiple difference frequency signals with the same frequency can be superimposed, so that a difference frequency signal with a stronger intensity can be obtained. After the difference frequency signal with a stronger intensity is recorded by the recording device, it can better interfere with the recorded sound signal, which is conducive to improving the interference effect and the anti-recording effect. In addition, the simultaneous emission of multiple ultrasonic waves with the same frequency can narrow the beam of the overall signal, further prevent the sound from being transmitted to the human ear, reduce the impact of noise on the eavesdropped person, and make it difficult for the eavesdropper to detect, so as to have higher security.

[0081] In one embodiment, if Figure 7 As shown, there are multiple driving circuits 12 and ultrasonic probes 13 in the ultrasonic transmitting module, and there is one ultrasonic probe 13 connected to each driving circuit 12 .

[0082] It should also be noted that, in order to ensure the driving effect of the ultrasonic probe 13 and improve the interference effect in the embodiment of the present invention, any ultrasonic transmitting module in the interference system may include a signal source 11, multiple driving circuits 12, and an ultrasonic probe 13 connected to each driving circuit 12. That is, the number of driving circuits 12 and ultrasonic probes 13 is the same, and one driving circuit 12 drives one ultrasonic probe 13. Figure 7 As shown. The signal source 11 in the ultrasonic transmission module sends the generated frequency signal to each driving circuit 12, and each driving circuit 12 generates a corresponding driving signal according to the frequency signal and drives the ultrasonic probe 13 connected thereto to transmit an ultrasonic wave of the corresponding frequency, so that the frequency of the ultrasonic wave emitted by each ultrasonic probe 13 is the same. Since a plurality of ultrasonic waves with the same frequency can generate a larger number of difference frequency signals with ultrasonic waves of other frequencies after being emitted, the intensity of the superimposed ultrasonic signal is greater, so that a difference frequency signal with a greater intensity can be obtained. After the difference frequency signal with a greater intensity is recorded by the recording device, it can better interfere with the recorded sound signal, which is beneficial to improving the interference effect and the anti-recording effect.

[0083] In one embodiment, if there are i types of ultrasonic emission modules, and each ultrasonic emission module includes an ultrasonic probe 13, the ultrasonic probes 13 of different ultrasonic emission modules may be arranged in sequence according to a trend of gradually increasing or gradually decreasing frequencies. Figure 8As shown, assuming that there are 4 types of ultrasonic modules, the corresponding frequencies are: f1, f2, f3, f4, and these four frequencies increase in frequency intervals of 150Hz, that is, 36KHz, 36.15KHz, 36.3KHz, 36.45KHz, then the ultrasonic probes of these four ultrasonic modules can be arranged from left to right. Such an arrangement makes the multiple 150Hz difference frequency signals generated after mixing closer, making it easier to superimpose multiple difference frequency signals, thereby improving the interference effect.

[0084] For long-distance, wide-range interference scenarios or recording shielding scenarios, in order to better ensure the interference effect and recording shielding effect, the ultrasonic transmitting module in the embodiment of the present invention includes two or more ultrasonic probes 13 of the same frequency. The ultrasonic probes 13 of the same frequency are arranged along the direction of gravity, so that the beam can be narrowed in the direction of gravity, that is, the energy of the narrowed beam is concentrated in the middle area, while the energy of the high and low areas is lower, which further prevents the sound from being transmitted to the human ear, reduces the impact of noise on the user, and is not easy for eavesdroppers to detect, which is more secure. In addition, since the beam is narrowed, the energy in the middle area is higher, and the power of the overall interference signal will also be enhanced, thereby further improving the interference effect and recording shielding effect. In practical applications, the interference system can be disguised as a speaker or other equipment to perform recording shielding on the recording equipment in the room.

[0085] For long-distance and wide-range interference scenarios or recording shielding scenarios, in order to further improve the interference effect and recording shielding effect, all ultrasonic probes 13 in multiple ultrasonic transmitting modules in another embodiment of the present invention are arranged in the form of n rows and m columns, and the ultrasonic probes 13 in the same ultrasonic transmitting module 1 are arranged in sequence along the gravity direction. Among them, n represents the number of ultrasonic probes in one ultrasonic transmitting module, and m represents the type of ultrasonic transmitting module.

[0086] For example, all ultrasonic probes 13 in the embodiment of the present invention may be arranged in n rows and m columns (for example Fig. 9 As shown, they are arranged in 4 rows and 4 columns, with four ultrasonic probes 13A arranged in the first column, four ultrasonic probes 13B arranged in the second column, four ultrasonic probes 13C arranged in the third column, and four ultrasonic probes 13D arranged in the fourth column. First, the ultrasonic probes 13 of the same frequency are arranged in a row (for example, four ultrasonic probes 13A). In the longitudinal direction (i.e., in the vertical direction), the energy of the beam is concentrated in the middle area, while the energy in the high and low areas is low. Therefore, the beam is narrowed in the longitudinal direction, thereby preventing the sound from being transmitted to the human ear. In addition, since the beam is narrowed, the power is more concentrated, which can further improve the interference effect. In addition, in the transverse direction (i.e., in the horizontal direction), the energy of the beam is more uniform, thereby ensuring the shielding range.

[0087] Fig.10 The figure is a comparison of the ultrasonic beams of the single probe solution and the multi-probe solution provided in this embodiment in two-dimensional coordinates. The horizontal axis represents the azimuth angle, and the vertical axis represents the normalized sound pressure level. A single probe refers to only one ultrasonic probe (corresponding to curve g1). A multi-probe solution refers to Fig. 9 The four ultrasonic probes shown have the same frequency and are arranged along the direction of gravity. The longitudinal direction refers to the ultrasonic beam curve along the longitudinal direction (corresponding to curve g3). The transverse direction refers to the ultrasonic beam curve along the transverse direction (i.e. horizontal direction) (corresponding to curve g2).

[0088] It should be noted that in the single-probe solution, if the same excitation signal strength as the multi-probe solution is used, the overall value of the single-probe curve will be lower, and it is not easy to reflect the difference between it and the multi-probe solution. Fig.10 In the illustrated embodiment, a stronger excitation signal is used for the single probe, while the intensity of the excitation signal for the multiple probes is relatively weak, in order to facilitate comparison between the two.

[0089] Specifically, compared with curve g1, in curve g3, the sound pressure level in the range of 80°-100° is higher than that in other angles, that is, the energy of the beam is concentrated in the area corresponding to this angle (that is, the middle area along the gravity direction), while the sound pressure levels in other angle intervals (corresponding to the high and low areas in the gravity direction) are all low, which proves that the ability of the beam in the longitudinal direction is concentrated in the middle area, achieving beam narrowing. At the same time, compared with curve g1, the sound pressure levels of the two side areas in the horizontal direction of curve g2 (the interval with an angle less than about 10 degrees and the interval with an angle greater than about 170 degrees) are increased relative to curve g1, that is, the difference in sound pressure levels at different positions in the horizontal direction is relatively reduced, which proves that the energy distribution in the horizontal direction is relatively uniform, thereby expanding the shielding range.

[0090] Fig.11 The figure is a comparison of the ultrasonic radiation direction of the single probe solution and the multi-probe solution provided in this embodiment in polar coordinates. Among them, 0-360° is the azimuth, and 0-1 is the normalized sound pressure level. Single probe refers to only one ultrasonic probe (corresponding to curve g1). Multi-probe solution refers to Fig. 9 The four ultrasonic probes shown have the same frequency, and these ultrasonic probes are arranged along the direction of gravity, wherein the longitudinal direction refers to the beam curve of the ultrasonic wave along the longitudinal direction (corresponding to curve g3). The transverse direction refers to the beam curve of the ultrasonic wave along the transverse direction (i.e., horizontal direction) (corresponding to curve g2). Specifically, Fig.11In the figure, compared with curve g1, the point of curve g3 near the angle of 90° is farthest from the center, that is, the radiation intensity near 90° is the highest, while the points in other angle intervals are far away from the boundary of the circle, which shows that the radiation intensity of the beam in this scheme is relatively concentrated and concentrated in the middle area of ​​the longitudinal direction. Compared with curve g1, the sound pressure level difference at different positions in curve g2 is relatively reduced, which proves that the energy distribution in the horizontal direction is relatively uniform, thereby expanding the shielding range.

[0091] Therefore, it can be seen from each curve that, compared with the related art, in the embodiment provided by the present invention, in the longitudinal direction (i.e., along the vertical direction), the energy of the beam is concentrated in the middle area, while the energy of the high and low areas is low, and the beam is narrowed. In the transverse direction, the energy of the beam is relatively uniform, thereby ensuring the shielding range.

[0092] In practical applications, the frequencies of the ultrasonic probes 13 in different columns decrease or increase in sequence along the arrangement direction of the columns, wherein the arrangement direction is parallel to the direction from one end to the other end of any row. That is, if the column is the gravity direction, the frequencies of the ultrasonic probes 13 decrease or increase in sequence along the horizontal direction, so that the ultrasonic frequencies of two adjacent columns are close, and the desired difference frequency signals can be better generated. In addition, the distance between the desired difference frequency signals will be closer, which facilitates the superposition of the desired difference frequency signals.

[0093] Please refer to Fig. 9 For example, along the horizontal direction, the frequencies of each ultrasonic probe increase in sequence. Among them, the frequency f1 of the ultrasonic waves emitted by each ultrasonic probe 13A in the first column is 36KHz, the frequency f2 of the ultrasonic waves emitted by each ultrasonic probe 13B in the second column is 36.15KHz, the frequency of the ultrasonic waves emitted by each ultrasonic probe 13C in the third column is 36.3KHz, and the frequency f4 of the ultrasonic waves emitted by each ultrasonic probe 13D in the fourth column probe group is 36.45KHz. Therefore, the ultrasonic probes in each adjacent column (for example, ultrasonic probe 13A and ultrasonic probe 13B, ultrasonic probe 13B and ultrasonic probe 13C, ultrasonic probe 13C and ultrasonic probe 13D) can generate a 150Hz difference frequency signal, and for each adjacent ultrasonic probe in each row (for example, ultrasonic probes 13A to 13D in any row), at least three 150Hz difference frequency signals can be generated. Different difference frequency signals with the same frequency can be superimposed on each other to generate stronger interference signals, which can better ensure the interference effect and anti-recording effect in the case of long-distance transmission.

[0094] Below Fig. 9For example, the interference system in the embodiment of the present invention includes four ultrasonic transmitting modules, and each ultrasonic transmitting module includes four ultrasonic probes 13. The frequency of the ultrasonic waves emitted by the four ultrasonic probes 13A corresponding to one ultrasonic transmitting module is f1, the frequency of the ultrasonic waves emitted by the four ultrasonic probes 13B corresponding to another ultrasonic transmitting module is f2, the frequency of the ultrasonic waves emitted by the four ultrasonic probes 13C corresponding to another ultrasonic transmitting module is f3, and the frequency of the ultrasonic waves emitted by the four ultrasonic probes 13D corresponding to another ultrasonic transmitting module is f4. All ultrasonic probes 13 are arranged in 4 rows and 4 columns. Among them, the ultrasonic probes 13 of the same ultrasonic transmitting module are arranged along the direction of gravity. Fig. 9 As shown, each ultrasonic probe 13A is located in the first column, each ultrasonic probe 13B is located in the second column, each ultrasonic probe 13C is located in the third column, and each ultrasonic probe 13D is located in the fourth column, and each column is along the gravity direction. Since the frequency of the ultrasonic waves emitted by the ultrasonic probes 13 in each column is the same, and the frequencies of the ultrasonic waves emitted by the ultrasonic probes 13 in different columns are different, the interference signals emitted by the ultrasonic probes 13 in different columns can be mixed with each other to generate difference frequency signals, and there are multiple difference frequency signals of the same frequency, thereby improving the interference effect.

[0095] On the basis of the above-mentioned embodiment, another aspect of the embodiment of the present invention further provides a recording shielding device including the above-mentioned interference system.

[0096] Specifically, for the above-mentioned long-distance, wide-range interference scenario or recording shielding scenario, in one embodiment, please refer to Fig.12 The recording shielding device includes a mounting body 2, and at least one interference system 10 is disposed on at least one side wall of the mounting body 2. The interference system 10 can refer to the above embodiments. The interference system 10 includes a variety of ultrasonic emission modules, and various ultrasonic emission modules include one or more ultrasonic probes with the same frequency. The ultrasonic probes of different frequencies in the interference system 10 are arranged in sequence along the horizontal direction, and the ultrasonic probes of the same frequency can be arranged in sequence along the direction of gravity. For example, Fig.12 In the interference system 10 on a side wall, ultrasonic probes in the same column emit ultrasonic waves of the same frequency, and ultrasonic probes in different columns emit ultrasonic waves of different frequencies. Therefore, corresponding difference frequency signals will be generated between the interference signals emitted by ultrasonic probes in different columns of the same side wall, and there are multiple difference frequency signals with the same frequency, so that the recording equipment placed in the corresponding direction of the side wall can be well shielded. For each side wall with an interference system, the recording equipment placed in the corresponding direction can be shielded, so that the large range around the recording shielding equipment can be shielded, and the overall effect is good.

[0097] In addition, the interference system provided by the embodiment of the present application can also be applied to close-range, centralized application scenarios. When performing interference or recording shielding, 4 or more ultrasonic transmitting modules can be set in the interference system 10, and the ultrasonic transmitting module includes one or more ultrasonic probes with the same frequency. The interference system 10 includes one or more probe sets, each probe set includes i ultrasonic probes with different frequencies. In a probe set, each ultrasonic probe is arranged in z rows and k columns. Wherein z represents the number of rows, and z ≥ 2. k represents the number of columns, and k ≥ 2.

[0098] Since it is used in close-range, centralized recording shielding scenarios, considering the requirement of small space for distance recording shielding, ultrasonic probes of different frequencies can be placed together. All ultrasonic probes in each ultrasonic transmitting module constitute at least one probe set, and each probe set includes i ultrasonic probes with different frequencies, so that multiple difference frequency signals are generated between the ultrasonic waves emitted by the ultrasonic probes of different frequencies in each probe set. After multiple difference frequency signals can be more effectively recorded by the microphone of a close-range recording device, they can well interfere with the recorded sound signal to be recorded by the recording device, thereby preventing the normal playback of the recorded sound signal and achieving the purpose of anti-recording.

[0099] In addition, the arrangement of the ultrasonic probes in the embodiment of the present invention (the above-mentioned z rows and k columns) can be applied to interference systems in close-range, concentrated recording shielding scenarios. It occupies a small space, has a high degree of concentration, and can more effectively input noise signals into close-range microphones, thereby meeting the small space requirements of close-range recording shielding.

[0100] In some embodiments, the interference system 10 includes four ultrasonic transmitting modules, each ultrasonic transmitting module has an ultrasonic probe, then the interference system may include a probe set, the probe set may include four ultrasonic probes with different frequencies, which can be arranged in 2 rows and 2 columns.

[0101] In other embodiments, Fig.13 As shown, the interference system 10 may include 4 types of ultrasonic transmitting modules, each of which has 2 ultrasonic probes. The interference system may include 2 probe sets 101, each of which includes 4 ultrasonic probes with different frequencies, which may be arranged in 2 rows and 2 columns.

[0102] For example, Fig.13As shown, in any probe set 101, an ultrasonic probe with a frequency f2 of 36.15KHz can be set below an ultrasonic probe with a frequency f1 of 36KHz, an ultrasonic probe with a frequency f3 of 36.3KHz can be set to the right of an ultrasonic probe with a frequency f1 of 36KHz, and an ultrasonic probe with a frequency f4 of 36.45KHz can be set below an ultrasonic probe with a frequency f4 of 36.3KHz. Of course, in actual applications, the positions of the ultrasonic probes of these four frequencies can be selected and adjusted by those skilled in the art according to actual needs.

[0103] Of course, in the case where each ultrasonic transmitting module includes multiple ultrasonic probes in the embodiment of the present invention, the number of probe sets 101 can be multiple. Multiple probe sets 101 can be arranged in sequence along the first direction or the second direction, and the first direction and the second direction are perpendicular to each other. Among them, the first direction is, for example, the horizontal direction, and the second direction is, for example, the direction of gravity. The multiple difference frequency signals generated by each probe set 101 can be better recorded by the microphone of the recording device, further improving the interference effect on close-range and concentrated scenes. In addition, the number of probe sets 101 has increased, which can cover the shielded recording device in multiple directions, reduce the demand for the placement of the recording device, and improve applicability.

[0104] For example, Fig.13 As shown, the two probe sets 101 can be arranged in the horizontal direction. Of course, in actual applications, the two probe sets 101 can also be arranged in the gravity direction. The number and arrangement direction of the probe sets 101 can be selected and adjusted by those skilled in the art according to actual needs.

[0105] Specifically, for close-range, centralized application scenarios, another recording shielding device is provided in the embodiment of the present invention, please refer to Fig.14 The recording shielding device includes the above-mentioned interference system and a box body 3, wherein a receiving cavity 20 for carrying the device to be interfered is formed inside the box body 3, and a side opposite to the bottom wall of the receiving cavity 20 is open. Various ultrasonic emission modules include one or more ultrasonic probes with the same frequency, and the ultrasonic probes are arranged between the outer wall 30 of the box body 3 and the receiving cavity 20.

[0106] In practical applications, the recording device to be interfered can be placed in the accommodating cavity 20 of the recording shielding device, and the various ultrasonic emission modules in the interference system 10 generate ultrasonic waves of different frequencies. After the difference frequency signals between ultrasonic waves of different frequencies are recorded by the microphone of the recording device placed in the accommodating cavity 20, they interfere with the recorded sound signals recorded at the same time, causing the recorded sound signals to be unable to be heard normally, thereby achieving recording shielding of the recording device. In addition, since ultrasonic waves can be reflected in the accommodating cavity 20, the ultrasonic waves in the recording shielding device are not easy to propagate to the human ear and will not affect the eavesdropped person.

[0107] In some embodiments, Fig.14 As shown, the cross-section of the accommodating cavity 20 is rectangular, and the area of ​​the rectangle is larger than the area of ​​the commonly used recording devices (such as mobile phones and tablets) on the market, which is convenient for placing and taking out the recording devices. In addition, a variety of ultrasonic emission modules are arranged on the inner wall of at least one of the two opposite sides of the accommodating cavity 20 in the length direction of the rectangle. Under this arrangement, the emission direction of the generated difference frequency signal is directly toward the microphone at the bottom and / or top of the recording device, and the interference effect will be better. In the recording shielding device provided in this embodiment, the interference system can adopt the above-mentioned Fig.13 The setting shown in the figure makes the interference system occupy a small space and has a high degree of concentration. It can more effectively input the interference signal to the microphone at a close distance, and can meet the small space requirement for close-range recording shielding.

[0108] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0109] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0110] 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.

Claims

1. A jamming system, characterized in that: It includes i types of ultrasonic emission modules; among which: The ultrasonic transmitting module is used to transmit ultrasonic waves; the frequencies of ultrasonic waves transmitted by different types of ultrasonic transmitting modules are different; the absolute value of the frequency difference of ultrasonic waves transmitted by any two types of ultrasonic transmitting modules is smaller than the frequency of ultrasonic waves transmitted by any type of ultrasonic transmitting modules; i≥2.

2. The jamming system according to claim 1, characterized in that: The frequency difference ranges from 150 Hz to 200 Hz.

3. The jamming system according to claim 1, characterized in that: The frequencies of the ultrasonic waves of the various ultrasonic transmitting modules can be sorted in a preset order, and the absolute value of the frequency difference between any two adjacent frequencies of the ultrasonic waves after sorting is the same.

4. The jamming system according to claim 1, characterized in that: The frequency range of the ultrasonic wave emitted by the ultrasonic wave transmitting module is 25KHz~40KHz.

5. The jamming system according to claim 1, characterized in that: There are 4 to 6 types of ultrasonic emission modules.

6. The jamming system according to any one of claims 1 to 5, characterized in that: The ultrasonic transmitting module comprises: A signal source, used for transmitting a frequency signal; at least one driving circuit connected to the signal source, configured to generate a driving signal based on the frequency signal; Each of the driving circuits is connected to at least one ultrasonic probe, and the ultrasonic probe is used to transmit ultrasonic waves of corresponding frequencies based on the driving signal.

7. The jamming system according to claim 6, characterized in that: The ultrasonic transmitting module has one driving circuit and multiple ultrasonic probes connected to the driving circuit.

8. The jamming system according to claim 6, characterized in that: There are multiple driving circuits and ultrasonic probes in the ultrasonic transmitting module, and there is one ultrasonic probe connected to each driving circuit.

9. The jamming system according to any one of claims 1 to 5, characterized in that: The ultrasonic transmitting module includes two or more ultrasonic probes with the same frequency; the ultrasonic probes with the same frequency are arranged along the direction of gravity.

10. The jamming system according to claim 9, characterized in that: All ultrasonic probes in multiple types of ultrasonic transmitting modules are arranged in the form of n rows and m columns, and the ultrasonic probes in the same type of ultrasonic transmitting module are arranged in sequence along the direction of gravity; wherein n represents the number of ultrasonic probes in one type of ultrasonic transmitting module, and m represents the type of ultrasonic transmitting module.

11. The jamming system according to claim 10, characterized in that: The frequencies of the ultrasonic probes in different columns decrease or increase in sequence along the arrangement direction of the columns, wherein the arrangement direction is parallel to the direction from one end to the other end of any row.

12. The jamming system according to any one of claims 1 to 5, characterized in that: The i≥4, each of the ultrasonic transmission modules includes one or more ultrasonic probes with the same frequency; the interference system includes one or more probe sets, each of the probe sets includes i ultrasonic probes with different frequencies; In one of the probe sets, the ultrasonic probes are arranged in a pattern of z rows and k columns, wherein z represents the number of rows, and z≥2; and k represents the number of columns, and k≥2.

13. The jamming system according to claim 12, characterized in that: i is 4, and all the ultrasonic probes in each probe set are arranged in the form of 2 rows and 2 columns.

14. The jamming system according to claim 12, characterized in that: There are multiple probe sets, and the multiple probe sets are arranged in sequence along the first direction or the second direction, and the first direction and the second direction are perpendicular to each other.

15. A recording shielding device, characterized in that: Comprising an interference system as described in any one of claims 1 to 14.

16. A recording shielding device, characterized in that: The recording shielding device includes a mounting body, and at least one side wall of the mounting body is provided with at least one interference system as described in any one of claims 1 to 11; the interference system includes a plurality of ultrasonic transmitting modules, and each of the ultrasonic transmitting modules includes one or more ultrasonic probes with the same frequency; the ultrasonic probes with different frequencies in the interference system are arranged in sequence in the horizontal direction.

17. A recording shielding device, characterized in that: The jamming system comprises the jamming system as claimed in any one of claims 12 to 14; the recording shielding device further comprises a box body, the interior of the box body is formed with a receiving cavity for carrying the device to be jammed; each of the ultrasonic emission modules comprises one or more ultrasonic probes with the same frequency; The ultrasonic probe is arranged between the outer wall of the box body and the accommodating cavity.

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