CN106059706B - A kind of mixing sound wave recording shielding device - Google Patents
A kind of mixing sound wave recording shielding device Download PDFInfo
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- CN106059706B CN106059706B CN201610353691.2A CN201610353691A CN106059706B CN 106059706 B CN106059706 B CN 106059706B CN 201610353691 A CN201610353691 A CN 201610353691A CN 106059706 B CN106059706 B CN 106059706B
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- 230000005855 radiation Effects 0.000 claims abstract description 11
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- 230000003321 amplification Effects 0.000 claims description 4
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 4
- 210000001367 artery Anatomy 0.000 claims 1
- 210000003462 vein Anatomy 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 9
- 230000001788 irregular Effects 0.000 abstract description 5
- 230000003595 spectral effect Effects 0.000 abstract description 5
- 230000006378 damage Effects 0.000 abstract description 4
- 229920006395 saturated elastomer Polymers 0.000 abstract description 4
- 230000005236 sound signal Effects 0.000 abstract description 4
- 238000001228 spectrum Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
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- 235000014676 Phragmites communis Nutrition 0.000 description 1
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- 150000001875 compounds Chemical class 0.000 description 1
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- 238000005315 distribution function Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000000873 masking effect Effects 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
- H04K3/00—Jamming of communication; Counter-measures
- H04K3/80—Jamming or countermeasure characterized by its function
- H04K3/82—Jamming or countermeasure characterized by its function related to preventing surveillance, interception or detection
- H04K3/825—Jamming or countermeasure characterized by its function related to preventing surveillance, interception or detection by jamming
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
- H04K3/00—Jamming of communication; Counter-measures
- H04K3/60—Jamming involving special techniques
- H04K3/62—Jamming involving special techniques by exposing communication, processing or storing systems to electromagnetic wave radiation, e.g. causing disturbance, disruption or damage of electronic circuits, or causing external injection of faults in the information
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
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- Physics & Mathematics (AREA)
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- Soundproofing, Sound Blocking, And Sound Damping (AREA)
- Noise Elimination (AREA)
Abstract
The present invention discloses a kind of mixing sound wave recording shielding device, including power supply unit, control unit, modulation unit, element of noise, high-frequency emission unit, radio frequency units, power amplifier unit, PTZ unit and electromagnetic pulse unit；The element of noise includes white noise generator and pink noise generator.The present invention is mixed sound wave recording shielding device and is emitted using ultralow frequency, is directly blocked the receiving end of sonic transducer, can not be extracted after being saturated it and restore received sound signal, and will not bring harm to human body and environment simultaneously.Effective noise source is chosen, Different Modulations are used to noise source, make modulated noise source is irregular to seek, and use effective radiation pattern, transmitting range is remote as far as possible, spectral coverage is big as far as possible, saturation effect is good etc. as far as possible requires to reach.
Description
Technical field
The present invention relates to the engineering device technique fields for monitoring or monitoring telecommunication, relate generally to a kind of mixing sound wave recording shielding
Device.
Background technique
Currently with the rapid development of science and technology, the miniaturization of the universal and electronic product of electronic product, it is personal with
And the threat that public information security is subject to is also increasing.Certain criminals pass through mobile phone, recording pen or other professions
Property stronger miniature interception facility, individual privacy, business secret even state secret are illegally stolen, to make personal, enterprise
Industry suffers economic loss, and more even person makes nation's security be on the hazard.
Most of sound pick-up outfit is all that voice signal is acquired by acoustoelectric sensor now, and the propagation of sound is one
Kind mechanical wave, is propagated in air by vibration.Acoustoelectric sensor acquires signal by incuding this vibration；If
In the sound pick-up outfit course of work, the vibrating reed of acoustoelectric sensor is set to sense a kind of irregular similar white noise by certain device
The vibration of sound, and not heard again by human ear so that sound pick-up outfit can only record a kind of noise, and people's one's voice in speech by
Thoroughly interference can not be separated；To effectively achieve the effect that recording interference.
Therefore, the existing technology needs to be improved and developed.
Summary of the invention
In view of above-mentioned deficiencies of the prior art, it records and shields the purpose of the present invention is to provide a kind of new mixing sound wave
Device can effectively interfere sound pick-up outfit, prevent it from normally realizing recording.
Technical scheme is as follows:
A kind of mixing sound wave recording shielding device, wherein including power supply unit, control unit, modulation unit, element of noise,
High-frequency emission unit, radio frequency units, power amplifier unit, PTZ unit and electromagnetic pulse unit；The power supply unit is needed with other
The unit to be powered is connected, and the unit for powering for other needs provides power supply；Described control unit and element of noise it is defeated
Outlet is connected with the input terminal of modulation unit respectively, and control unit is for generating carrier signal and carrier signal being sent to modulation
Unit, element of noise is for generating noise；The output end of the modulation unit respectively with high-frequency emission unit, less radio-frequency list
Member, the input terminal of power amplifier unit are connected, and the modulation unit is used to carrier signal noise is added, and are modulated to noise；It is high
Frequency transmitting unit is used to receive the waveform of modulation unit output and emits HF noise signal, and the radio frequency units are for connecing
It receives the waveform of modulation unit output and emits less radio-frequency noise signal；The output end of power amplifier unit respectively with PTZ unit and electricity
The input terminal of magnetic field impulse unit is connected, and power amplifier unit is used to receive the waveform of modulation unit output and sends after carrying out power amplification
To PTZ unit and electromagnetic pulse unit, PTZ unit is used to receive the waveform of power amplifier unit and emits low-frequency noise signal, electromagnetism
Pulse unit is used to receive the concurrent radio magnetic field impulse interference signal of waveform of power amplifier unit；The element of noise includes white noise hair
Raw device and pink noise generator.
The mixing sound wave recording shielding device, wherein control unit is single-chip microcontroller, and the carrier signal of generation includes sine
It is one or more in wave, triangular wave, square wave and narrow pulse signal.
The mixing sound wave recording shielding device, wherein the modulation system of modulation unit includes amplitude modulation, frequency tune
One of system, phase-modulation are a variety of.
The mixing sound wave recording shielding device, wherein the resonance frequency of piezoelectric ceramic transducer is located at 16KHz or more.
The described mixing sound wave recording shielding device, wherein the dominant frequency setting of electromagnetic pulse unit 10KHz~20KHz it
Between.
The mixing sound wave recording shielding device, wherein the radiation radius of electromagnetic pulse unit is set as 5 meters.
Emitted the utility model has the advantages that the present invention mixes sound wave recording shielding device using ultralow frequency, directly blocks connecing for sonic transducer
Receiving end can not be extracted after being saturated it and restore received sound signal, and will not bring simultaneously to human body and environment
Harm.It chooses effective noise source (including white noise and pink noise), Different Modulations is used to noise source, after making modulation
Noise source it is irregular seek, and use effective radiation pattern, transmitting range is remote as far as possible, spectral coverage is most to reach
Amount is big, saturation effect is good etc. as far as possible requires.
Detailed description of the invention
Fig. 1 is the functional block diagram of present invention mixing sound wave recording shielding device.
Fig. 2 is filter circuit figure.
Fig. 3 is the time domain waveform of white noise and pink noise.
Specific embodiment
The present invention provides a kind of mixing sound wave recording shielding device, to make the purpose of the present invention, technical solution and effect more
Clear, clear, the present invention is described in more detail below.It should be appreciated that specific embodiment described herein is only used to
It explains the present invention, is not intended to limit the present invention.
Mixing sound wave recording shielding device provided by the present invention, as shown in Figure 1, including power supply unit, control unit, modulation
Unit, element of noise, high-frequency emission unit, radio frequency units, power amplifier unit, PTZ unit (piezoelectric ceramics transducing unit) and
Electromagnetic pulse unit；The power supply unit is connected with the unit that other needs are powered, and the unit powered for other needs provides electricity
Source；The output end of described control unit and element of noise is connected with the input terminal of modulation unit respectively, and control unit is for generating
Carrier signal is simultaneously sent to modulation unit by carrier signal, and element of noise is for generating noise；The output end of the modulation unit
It is connected respectively with the input terminal of high-frequency emission unit, radio frequency units, power amplifier unit, the modulation unit is for believing carrier wave
Number be added noise, noise is modulated；High-frequency emission unit is used to receive the waveform of modulation unit output and emits high frequency and makes an uproar
Acoustical signal, the radio frequency units are used to receive the waveform of modulation unit output and emit less radio-frequency noise signal；Power amplifier
The output end of unit is connected with the input terminal of PTZ unit and electromagnetic pulse unit respectively, and power amplifier unit is for receiving modulation unit
The waveform of output simultaneously carries out being sent to PTZ unit and electromagnetic pulse unit after power amplification, and PTZ unit is for receiving power amplifier unit
Waveform and emit low-frequency noise signal, electromagnetic pulse unit be used for receive power amplifier unit waveform and emit electromagnetic pulse interference
Signal.Described control unit is single-chip microcontroller, can produce any one signal such as sine wave, triangular wave, square wave and narrow pulse signal.
The element of noise includes white noise generator and pink noise generator.
Noise is divided into white noise, pink noise, blue noise etc., and the present invention mixes sound wave recording shielding device selection and makes an uproar at random
Sound is commonly known as white noise as interference noise source, random noise.When interfering process power density is to timing, white noise has
Maximum masking characteristics, probability-distribution function are multiple normal distribution.Therefore, the element of noise in embodiments of the present invention
For white noise generating unit.For the complexity for increasing interference source, this equipment also uses pink noise.
In order to effectively utilize jamming resource, it is desirable in a certain range by noise spectrum limitation, however it is any
Noise source (white noise selected including present invention mixing sound wave recording shielding device), although its spectral range is very wide, and exactly exists
It is but very low that the present invention mixes its power spectral density of low-frequency range desired by sound wave recording shielding device.In order to which the low frequency for obtaining satisfied is made an uproar
Sound can move noise frequency, so that it becomes the low-frequency noise since 10Hz.
Specifically, the present invention is mixed sound wave recording shielding device and is emitted using ultralow frequency, directly blocks the reception of sonic transducer
End can not extract after being saturated it and restore received sound signal, and will not bring danger to human body and environment simultaneously
Evil.Effective noise source is chosen, Different Modulations are used to noise source, make modulated noise source is irregular to seek, and adopt
With effective radiation pattern, to reach, transmitting range is remote as far as possible, spectral coverage is big as far as possible, saturation effect is good etc. as far as possible is wanted
It asks.
To white noise, both noise sources of pink noise use three kinds of interference modulation systems: amplitude modulation, frequency modulation(PFM),
Phase-modulation, and modulation system and combinations thereof be it is random, it is irregular, be saturated sensor, i.e. the received language of sonic transducer
It can not extract and restore after the disturbed obstruction of sound signal.The present invention mixes noise-modulated carrier signal in sound wave recording shielding device
Any one signal such as sine wave, triangular wave, square wave and narrow pulse signal can be used.Amplitude, frequency are used to the modulation of noise
With the compound modulation of phase, while optimal interference effect can get using three kinds of modulation systems.Interference spectrum relative to
Carrier frequency is symmetrical, and interference band is equal to twice of modulation spectrum bandwidth.Modulation depth increase in the case where, when occur clipping and excessively
When modulation, due to there is combination component, interference spectrum is slightly widened.In this way, amplitude zoop frequency spectrum is completely by zoop
Frequency spectrum determines.
About energy converter, as the piezoelectric ceramic transducer of very low frequencies emitter, working frequency is preferably in low frequency
At 2KHz~5KHz, because the voice of this section of frequency band is most abundant, but this section of frequency band is also the most sensitive part of human ear, in order to reduce
Stimulation to human body, the present invention mix sound wave recording shielding device and the resonance frequency of piezoelectric ceramic transducer are located at 16KHz or more.
About the launching technique of interference signal, the low frequency electromagnetic pulse of use, wherein most energy concentrates on 100KHz
Hereinafter, dominant frequency is between 10KHz~20KHz, and its emitted energy is lower, will not generate harm to human body.
About electromagnetic pulse on the interference of microelectronic device, device and influence, the interference threshold of electromagnetic pulse field is about
1.3KV/m, damage threshold are about 40KV/m.Low frequency electromagnetic pulse employed in this equipment, it is contemplated that electrical, electronics around
The influence of equipment, transmission power is smaller, thus radiation scope is limited, and about 5 meters of radiation radius or so.
About the parameter of radiating antenna, radiating antenna parameter is to reinforce the radiation effect of electromagnetic impulse source, need to use antenna.
And difference (the i.e. high-frequency and low-frequency difference of the bandwidth of the antenna generally frequency corresponding to the half power points side-draw of centre frequency two
Value).The calculating of electric field strength and radiant power:
The radius for taking sonic transducer is 1.5mm, then the received radiant power P5 on sonic transducer at radiation source 5m:
P5=π r2×PW=3.675 × 10-6(W)。
The undistorted maximum output voltage of sonic transducer is 4.2V, input impedance > 5M Ω, the then output work on sonic transducer
Rate Pout≤3.528×10- 6(W), so having: Pout< P5, the radiation scope of this equipment is at 5 meters or so.
To enhanced rad effect, radiant power can be improved, or suitably increase antenna length.Other spokes can also be selected
Penetrate that effect is more preferable, the broader antenna of frequency band.By the selection of radiating antenna and its calculating of radiation field, show electrical dipole antenna
Radiation effect is most strong in the plane perpendicular to polar axis, and field strength is zero on polar axis.And the radiant power for improving antenna can
Expand the radiation scope and effect of noise jamming model machine.
The present invention is mixed sound wave recording shielding device and is powered using 6V~24V DC power supply, is with white noise and pink noise
Permutation and combination as modulated signals, when using sine wave, triangular wave, square wave, burst pulse as carrier wave.The present invention mixes sound wave
The course of work of recording shielding device is that noise (including white noise and pink noise) signal and single-chip microcontroller that element of noise generates produce
Raw carrier signal, by modulation unit carry out amplitude modulation, frequency modulation, phase modulation hybrid modulation after, be divided into three part；A part is given
The noise inputs end of high-frequency emission unit, i.e. radio circuit part directly emit HF noise signal by radio circuit, and cover has
With signal, to interference and block normal recording；A part of modulated noise signal is through radio frequency units (miniature low-power consumption
Module FM-1505) transmitting, radio-frequency region is 70MHz~110MHz, only with one piece of button cell can long-term work, diameter
For 10mm, thickness is only 2.5mm, and can the trimmer of external 20pF change its tranmitting frequency, transmitting range is greater than 30 meters；
A part of modulated noise signal drives PZT unit and the transmitting of electromagnetic pulse unit after power amplifier unit carries out power amplification
Low frequency signal and electromagnetic pulse signal.
White noise can be being had chosen about the realization of frequency shift filter for the complexity for increasing interference noise source
On the basis of, it can use filter white noise, i.e. every hertz of constant energy, be transformed into the constant energy of every octave
Pink noise.And pink noise is realized with filter can also reduce the low frequency wonder of noise signal.Filter circuit is such as
Shown in Fig. 2, therefore, it further includes a filter that the present invention, which mixes sound wave recording shielding device, and the filter is connected with element of noise.
The filter covers the audio range of 10Hz~20KHz, utilizes three pole operational amplifiers, it is possible to provide every ten octaves -20dB
Transmission characteristic, and frequency characteristic is unrelated with source impedance and load impedance.The time domain wave of obtained white noise and pink noise
In Fig. 3 shown in (a) and (b).
It should be understood that the application of the present invention is not limited to the above for those of ordinary skills can
With improvement or transformation based on the above description, all these modifications and variations all should belong to the guarantor of appended claims of the present invention
Protect range.
Claims (6)
1. a kind of mixing sound wave recording shielding device, which is characterized in that including power supply unit, control unit, modulation unit, noise list
Member, high-frequency emission unit, radio frequency units, power amplifier unit, piezoelectric ceramics transducing unit and electromagnetic pulse unit；The power supply
Unit is connected with the unit that other needs are powered, and the unit for powering for other needs provides power supply；Described control unit and
The output end of element of noise is connected with the input terminal of modulation unit respectively, and control unit is for generating carrier signal and believing carrier wave
It number is sent to modulation unit, element of noise is for generating noise；The output end of the modulation unit respectively with high-frequency emission unit,
Radio frequency units, power amplifier unit input terminal be connected, the modulation unit is used to carrier signal noise is added, to noise into
Row modulation；High-frequency emission unit is used to receive the waveform of modulation unit output and emits HF noise signal, the less radio-frequency
Unit is used to receive the waveform of modulation unit output and emits less radio-frequency noise signal；The output end of power amplifier unit respectively with pressure
Electroceramics transducing unit is connected with the input terminal of electromagnetic pulse unit, and power amplifier unit is used to receive the waveform of modulation unit output simultaneously
It is sent to piezoelectric ceramics transducing unit and electromagnetic pulse unit after carrying out power amplification, piezoelectric ceramics transducing unit is for receiving function
It puts the waveform of unit and emits low-frequency noise signal, electromagnetic pulse unit is used to receive the concurrent radio magnetic arteries and veins of waveform of power amplifier unit
Rush interference signal；Using low frequency electromagnetic pulse when emitting electromagnetic pulse interference signal；The element of noise includes white noise
Generator and pink noise generator.
2. mixing sound wave recording shielding device according to claim 1, which is characterized in that control unit is single-chip microcontroller, is generated
Carrier signal include one or more in sine wave, triangular wave, square wave and narrow pulse signal.
3. mixing sound wave according to claim 1 recording shielding device, which is characterized in that the modulation system of modulation unit includes
One of amplitude modulation, frequency modulation(PFM), phase-modulation are a variety of.
4. mixing sound wave recording shielding device according to claim 1, which is characterized in that the resonance of piezoelectric ceramics transducing unit
Frequency is located at 16KHz or more.
5. mixing sound wave recording shielding device according to claim 1, which is characterized in that the dominant frequency of electromagnetic pulse unit is arranged
Between 10KHz~20KHz.
6. mixing sound wave recording shielding device according to claim 1, which is characterized in that the radiation radius of electromagnetic pulse unit
It is set as 5 meters.
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| CN201610353691.2A CN106059706B (en) | 2016-05-24 | 2016-05-24 | A kind of mixing sound wave recording shielding device |
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| CN106059706B true CN106059706B (en) | 2019-01-15 |
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| CN109147795B (en) * | 2018-08-06 | 2021-05-14 | 珠海全志科技股份有限公司 | Voiceprint data transmission and identification method, identification device and storage medium |
| CN110190825B (en) * | 2019-06-28 | 2023-08-15 | 南通东峘电子科技有限公司 | Low frequency harmonic wave instrument |
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| WO2006100147A1 (en) * | 2005-03-24 | 2006-09-28 | Robert Bosch Gmbh | Method for damping a high-frequency radiation of a clocked system |
| CN102594483A (en) * | 2012-03-08 | 2012-07-18 | 南京泰之联无线科技有限公司 | Full-band examination place radio signal shielding device |
| CN103248980A (en) * | 2013-05-15 | 2013-08-14 | 中国人民解放军国防科学技术大学 | Method and device for generating low-frequency sound wave |
| CN105306162A (en) * | 2015-10-29 | 2016-02-03 | 天津光电安辰信息技术有限公司 | Mixing-based recording shielding device and realizing method thereof |
| CN205142236U (en) * | 2015-10-29 | 2016-04-06 | 天津光电安辰信息技术有限公司 | Recording shield assembly of mixing |
-
2016
- 2016-05-24 CN CN201610353691.2A patent/CN106059706B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006100147A1 (en) * | 2005-03-24 | 2006-09-28 | Robert Bosch Gmbh | Method for damping a high-frequency radiation of a clocked system |
| CN102594483A (en) * | 2012-03-08 | 2012-07-18 | 南京泰之联无线科技有限公司 | Full-band examination place radio signal shielding device |
| CN103248980A (en) * | 2013-05-15 | 2013-08-14 | 中国人民解放军国防科学技术大学 | Method and device for generating low-frequency sound wave |
| CN105306162A (en) * | 2015-10-29 | 2016-02-03 | 天津光电安辰信息技术有限公司 | Mixing-based recording shielding device and realizing method thereof |
| CN205142236U (en) * | 2015-10-29 | 2016-04-06 | 天津光电安辰信息技术有限公司 | Recording shield assembly of mixing |
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