CN208300016U - A kind of audio beam loudspeaker - Google Patents
A kind of audio beam loudspeaker Download PDFInfo
- Publication number
- CN208300016U CN208300016U CN201721117794.5U CN201721117794U CN208300016U CN 208300016 U CN208300016 U CN 208300016U CN 201721117794 U CN201721117794 U CN 201721117794U CN 208300016 U CN208300016 U CN 208300016U
- Authority
- CN
- China
- Prior art keywords
- audio
- signal
- sound
- loudspeaker
- audio beam
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Abstract
The utility model discloses a kind of audio beam loudspeakers, including casing, the more than one ultrasonic transducer being set in casing, ultrasonic transducer is installed on pcb board, pcb board is installed in casing, is also equipped with infrared sensor on the casing, after someone passes through, infrared sensor can give signal processing mainboard trigger signal, and entire loudspeaker is activated to play sound to target area.The ultrasonic wave audio frequency carrier signal for being modulated with voice signal is emitted in air with sound transducer array, due to the high directional property of ultrasonic wave, on ultrasonic beam direction, non-linear interaction occurs for air molecule and ultrasonic wave, audible sound is generated to reduce and be transformed into the audible low-frequency spectra of human ear for ultrasonic wave high-frequency signal, the significant by-products of this process are that sound wave can be narrowly focused towards on certain the determination direction listened in environment, and propagation distance is farther out.
Description
Technical field
The utility model relates to a kind of loudspeakers, and in particular to a kind of audio beam loudspeaker.
Background technique
Audio beam loudspeaker technology be it is a kind of when being propagated in air using the ultrasonic signal of different frequency due to sky
The nonlinear interaction of gas medium and the technology with audible difference frequency signal generated.Current audio frequency directional system in the world is also all
In laboratory sample to the product transformation stage, there is also many key theories and key technology to need to be broken through, and such as signal processing, changes
Can device production and power amplification etc. theory and technology.The main problem that audio frequency directional system faces at present be how
Audio transmission efficiency and sound quality are improved, audio transmission efficiency and sound quality problem are always to influence the application of audio frequency directional System Development
Principal element.
The AF energy that audio beam loudspeaker system generates usually only accounts for transmitting ultrasonic wave gross energy very little one
Point, this patent uses the higher D class power amplifier of amplification efficiency.D class power amplifier is obtained compared to the amplification efficiency of A class, AB class power amplifier
Greatly promoted.
But after amplification efficiency gets a promotion, audio system can integrally exist biggish total harmonic distortion (THD), reduce
The THD of D class power amplifier has biggish realistic meaning to the efficiency of audio frequency directional system, tone quality improving.This patent is for overall humorous
Wave distortion, which proposes intermodulation distortion backoff algorithm, reduces the THD of total system.
Audio beam loudspeaker system generallys use ultrasonic transducer as transmitting equipment, the performance characteristic of ultrasonic transducer
Directly determine the audio transmission efficiency and sound quality of audio frequency directional system.Meanwhile ultrasonic transducer is a kind of strong nonlinearity time-varying
System, the characteristic differences such as impedance are very big under different working frequencies.
There are some sound focusing loudspeakers based on principle of reflection on the market is also known as poly- sound cover at present.Configure transparent material
The acoustic reflection shell of 20 ~ 30in of diameter carries out poly- sound by parabola shaped sound reflecting structure, but whole poly- sound effective value and pays no attention to
Think, the effect of direction propagation sound cannot be fully achieved.Therefore the directional loudspeaker based on parametric array technology is produced.
Realize that the techniqueflow of parametric array loudspeaker can be sketched are as follows: (1) carry out at signal to the audio signal of input
Reason, wherein mainly in two steps, the first step is intermodulation distortion processing to signal processing, and second step is to believe pretreated audio
Number with ultrasonic carrier signal carry out amplitude modulation, generate ultrasonic carrier modulated signal；(2) by the modulated signal power amplification
After device amplification, it is emitted in air by ultrasonic transmitter, what is generated when being propagated in air using the signal is non-linear
Self demodulation of effect regenerates audio signal.Wherein, signal processing and ultrasonic transmitter part are parametric array loudspeakings
The key that device is realized and further developed.
The loudspeaker generally used in daily life at present is essentially all conventional loudspeakers, in this loudspeaker, no matter is passed
Which kind of structure is the design of sensor be, all the common ground with one " directly transmitting ", in principle is directly swashed by a particular organization
It encourages air molecule movement and generates the sound wave that can be listened to.Because conventional loudspeakers have radiated element, its major defect be because
Distortion caused by the quality problems and emitting module of removable dynamic model, be distorted as caused by emitting module and the relevant issues that generate
It is respectively present in low frequency, in intermediate frequency and high frequency spectrum, using bass, middle pitch and high pitch loudspeaker can partly solve existing
Problem.
Summary of the invention
The technical problem to be solved by the utility model is to provide it is a kind of can with higher efficiency, the lower distortion factor, more
Strong power emission has the sound wave of more sharp directive property.It is enriched by modes such as Bluetooth transmission, USB flash disk reading, TF card readings
The mode of speaker human-computer interaction makes speaker more intelligent.
The utility model is achieved through the following technical solutions: a kind of audio beam loudspeaker, including casing, setting
More than one ultrasonic transducer in casing, ultrasonic transducer are installed on pcb board, and pcb board is installed in casing, described
Infrared sensor is also equipped on casing, after someone passes through, infrared sensor can give signal processing mainboard trigger signal, activation
Entire loudspeaker plays sound to target area.
Be equipped on the signal processing mainboard power supply adaptor, digital power amplifier, long distance signal transmission line interface terminal,
Volume adjustment knob, signal input port, infrared switch, infrared sensor, signal lamp and power switch, signal processing
Edge shield item is wrapped up outside mainboard, power supply adaptor is inserted into external power supply, and entire signal processing mainboard passes through remote controller
Long-range control.
It as a preferred technical solution, further include an audio input plate.
The audio input plate includes that bluetooth inputs, USB port inputs, TF RAM card is defeated as a preferred technical solution,
Enter.
It is provided with EQ key in the remote controller as a preferred technical solution, respectively Normal, Class,
Jazz, Rock, Bass and POP.
Ultrasonic transducer shares 139 as a preferred technical solution, and energy converter central point line constitutes 60 ° of angle rows
Column, energy converter pin line are arranged parallel to each other.
As a preferred technical solution, pcb board surrounding have 6 protrusions be screw fixing hole position, PCB entirely through bolt into
Row is fixed.
Audio beam loudspeaker is installed on desktop, metope or embedded ceiling or peace as a preferred technical solution,
Loaded on ground.
As a preferred technical solution, further include thering is acoustic beam to protect sound absorption structure, is laid with sound absorbing object in blocking surfaces.
The audio beam loudspeaker mainly includes audio input, power module, at signal as a preferred technical solution,
Manage circuit system and ultrasonic transducer.
A kind of method of intermodulation distortion processing, specifically includes:
(1) after audio signal input, it is multiplied by index of modulation m, Hilbert transform is done to it, then is squared operation, is led to
Cross calculating formula；
(2) single sideband modulation envelope square is found out.Wherein, distorterence term is then recycled and is calculated, due to distorterence term
Inside contains some DC component, it is therefore desirable to carry out DC filtering to distorterence term；
(3) it just completes after completing above a set of calculating to original input signalFirst compensation phase, however if want
It is as much as possible to get rid of intermodulation distortion caused by single sideband modulation, it needs pairCarry out multistage compensation；
(4) audio signal obtained before is re-used as original signal, iteration returns the most incipient stage again, recycles past
It is multiple, under normal circumstances, most intermodulation distortion can be eliminated iteration 2 to 3 times, gained signal can be exported be used as it at this time
The original signal of single sideband modulation afterwards.
The beneficial effects of the utility model are: the utility model audio beam loudspeaker is existed with entirely different technology
Sound wave is created in air indirectly.The system believes the ultrasonic wave audio carrier for being modulated with voice signal with sound transducer array
It number is emitted in air, due to the high directional property of ultrasonic wave, on ultrasonic beam direction, air molecule and ultrasonic wave occur non-
Linear reciprocal effect, so that reducing and be transformed into the audible low-frequency spectra of human ear for ultrasonic wave high-frequency signal generates audible sound,
The significant by-products of this process be sound wave can be narrowly focused towards listen to certain in environment determine on direction, and propagation distance
Farther out.
Detailed description of the invention
In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment
Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only
It is some embodiments of the utility model, for those of ordinary skill in the art, in the premise not made the creative labor
Under, it is also possible to obtain other drawings based on these drawings.
Fig. 1 is the structural schematic diagram of the transducer array strake of the utility model；
Fig. 2 is the super directional loudspeaker system general principles figure of the utility model；
Fig. 3 is the system block diagram of signal processing system；
Fig. 4 is single sideband modulation system block diagram；
Fig. 5 is the system block diagram of intermodulation distortion processing；
Fig. 6 is the structural schematic diagram of impedance matching network.
Specific embodiment
All features disclosed in this specification or disclosed all methods or in the process the step of, in addition to mutually exclusive
Feature and/or step other than, can combine in any way.
Any feature disclosed in this specification (including any accessory claim, abstract and attached drawing), except non-specifically chatting
It states, can be replaced by other alternative features that are equivalent or have similar purpose.That is, unless specifically stated, each feature is only
It is an example in a series of equivalent or similar characteristics.
As shown in Figure 1, introducing differential signal by left end signal receiving end 2, it is transported on ultrasonic transducer, pcb board
On share 139 energy converters 2,2 central point line of energy converter constitutes 60 ° of angles arrangements, energy converter pin line row parallel to each other
Column.6 protrusions 4 of pcb board surrounding are screw fixing hole position, and pcb board 3 is fixed entirely through bolt.
Power supply adaptor, digital power amplifier, long distance signal transmission line interface terminal, volume are installed on signal processing mainboard
Adjusting knob, signal input port, infrared switch, infrared sensor, signal lamp and power switch, signal processing mainboard
Outside package edge shield item, power supply adaptor are inserted into external power supply, and entire signal processing mainboard is long-range by remote controller
Control.
Audio input plate is integrated with a variety of audio input modes, including bluetooth input, USB port input, TF RAM card is defeated
Enter.
Bluetooth audio frequency receiver board supports the bluetooth equipment of newest V4.2, maximum transmission distance 15 under spacious barrier-free environment
Rice.
USB flash disk/TF RAM card playing function is supported the audio of five kinds of formats of WAV, WMA, FLAC, APE, MP3, be can be realized
Lossless audio, which reappears, to be played.
Product can operate the functional realization of institute by remote control, facilitate user to carry out remote control operation, there is better production
Product using effect.In audio mode, by remote controler, the operation of fast forwarding and fast rewinding can be carried out to song.A head in long-pressing
Key realize rewind function, long-pressing next key realize fast-forward functionality.
Same audio input plate can realize the input of a variety of audios, can be selected by EQ key.Respectively
Normal(is normal), Class(it is classic), Jazz(jazz), Rock(rock and roll), Bass(supper bass), POP(it is popular).Pass through table
Whether the pyroelectric human body infrared sensor for human detection in face is close, distance of reaction: 5-8 meters, the control of module overall output signal
The on-off action of total system.
Audio beam loudspeaker has directive property more stronger than ventional loudspeakers, can be at the position loudspeaker 5-10m
Hear clearly, give the sound of " whisper in one's ear " feeling, and whole hall range is still kept quite；If to left and right partially
It just can't hear sound completely from 1m.These three mounting means can bring preferable sound field effect, create ideal audition
Position.
Acoustic beam protects sound absorption structure
It is noted, however, that can occur when encountering hard obstructing objects (such as wall, cabinet) in propagation process of sound wave
Specular scattering is unable to get a preferably sound field and reappears so as to cause the uncontrollable situation of acoustic wave beam.Therefore in this feelings
Under condition, this patent statement reduces Beam Scattering situation caused by spatial obstacle using novel sound absorption structure, in barrier table
Face, which is laid with sound absorbing object, can guarantee the unicity of sound field.
It is formed according to audio frequency directional working principle and system, audio beam loudspeaker general system proposal is as shown in Fig. 2, packet
Including audio beam loudspeaker mainly includes audio input, power module, signal processing system circuit and ultrasonic transducer.
By audio input interface input original audio after, be sent into signal processing system circuit after, signal through oversampling circuit at
It is emitted after reason by ultrasonic transducer.Ultrasonic wave generates audible sound from demodulation due to nonlinear effect in air, will
Original audio input restores.
As shown in figure 3, wherein signal processing part is divided into the core of total system, mainly include signal processing platform,
Power amplifier and impedance matching network etc., wherein signal processing platform includes signal, filtering, A/D conversion and DSP etc.
Part.DSP is selected to be that it can realize that various signal processings are calculated by programming fast and flexible as the reason of primary processor
Method, compared with other digital signal processing platforms such as ARM, FPGA, ASIC, DSP system short, cost with the development cycle
The advantages that low and flexible in programming.
The source of sound of super directional system supports digital audio and analog audio input simultaneously, to adapt to different multimedias just
Portable device interface.Digital audio can be directly entered signal processing link without any conversion, alleviate letter for dsp processor
The burden that number conversion and digital cake resistancet come, enables a processor to more efficient processing audio frequency directional algorithm.For that cannot integrate
The equipment that audio frequency directional system does not have digital audio output interface yet may be used the reserved analog audio input of system and connect
Mouthful, analog audio signal filters out the outer ingredient of audible sound band other than 20Hz ~ 20kHz by conditioning and filter circuit, then by
A/D converter is converted to digital audio and video signals, into DSP processor.After audio signal is collected the inside DSP, by believing
Number Processing Algorithm carries out ultrasonic carrier modulation to audio signal, then send to digital power modulated signal in a digital manner and puts
Big device, the signal after being amplified enter matching network and do filtering and impedance conversion process, transducer vibrations sounding are driven, to air
In launch the ultrasonic wave for carrying audible acoustic intelligence.
Dynamic range refers to that pole electrostatic puts down " distance " extremely rung between level, the audio signal dynamic model of input in audio signal
It encloses and is often unable to control, first pass around dynamic after source material audio signal left and right acoustic channels input wider for some dynamic ranges
Ratage Coutpressioit.
Dynamic range control is centered on nominal source level.For being higher than the signal of the normal level critical point, electricity
Flat or loudness will be lowered;And the signal for being lower than the point, level or loudness will be enhanced.It is handled by dynamic range
Afterwards, audio signal improves clarity for whole, so that target audience is easier to understand.
Equalization filter:
Audio signal first passes through equalization filter, low frequency is promoted, to compensate envelope square in Berktay Far field solution
It is secondary to lead caused 12dB/ octave high boost.
High-pass filter filters out 150hz audio signal below
The purpose for being included in high-pass filter is that, when modulated signal is there are when the very low component of frequency, system is difficult efficiently
These signals are reappeared, therefore a large amount of energy dissipations can be made.
Low-pass filter filters out 15000hz audio signal below；
The purpose that low-pass filter is added is that, when carrier frequency is chosen to be 40kHz, difference frequency signal will be not less than 25kHz.
The sound wave of 25kHz is still in other than the audible sound range of people, therefore will not bring noise jamming for system.If be not added low
Bandpass filter, it will generate audible acoustic jamming, influence the final corresponding of system.
As shown in figure 4, it is single sideband modulation system block diagram, Hilbert transform (Hilbert) is in single sideband modulation SSB
Hilbert variation (Hilbert) transformation is applied to during modulation, being will letter in the case where not changing original signal skin quality
Number 90 degree of phase shift.
Xi Er transformation is to can be represented by the formula:
Intermodulation distortion processing
For single sideband modulation, when input is only simple signal, only only there are two frequencies in output signal
Component.Therefore the input signal of script can be demodulated to after the nonlinear effect of air.And when input signal is broadband signal
When, the signal of output will appear apparent intermodulation distortion.Therefore we be necessarily required to by signal processing algorithm to original signal into
Line distortion processing, reduces the intermodulation distortion of final output signal.
As shown in figure 5, being multiplied by index of modulation m after the input of (one) audio signal, Hilbert transform being done to it, then take
Square operation passes through calculating formula；
(2) single sideband modulation envelope square is found out.Wherein, distorterence term is then recycled and is calculated,
Due to containing some DC component inside distorterence term, it is therefore desirable to carry out DC filtering to distorterence term；
(3) first compensation phase to original input signal is just completed more than completing after a set of calculating, however can if to use up
It getting rid of intermodulation distortion caused by single sideband modulation energy more, needing to the multistage compensation of progress；
(4) audio signal obtained before is re-used as original signal, iteration returns the most incipient stage again, recycles past
It is multiple, under normal circumstances, most intermodulation distortion can be eliminated iteration 2 to 3 times, gained signal can be exported be used as it at this time
The original signal of single sideband modulation afterwards.
D-type power amplifier
Using D class digital power amplifier since transistor works in on-off mode, actual efficiency can achieve system
90% or more, energy loss is significantly reduced, and can realize high-power output with lesser volume, in a portable device
Extensive use is arrived, therefore, using the power amplification of D class switch amplifying technique design micro audio directional system in the design
Device.The basic principle of D power-like amplifier is that input signal is generated to pulse width modulation (PWM) compared with high frequency triangle wave
Signal, PWM signal are obtained via driving circuit driving rear class power device (such as switching transistor, MOS pipe) high-speed switch
Amplified PWM wave, the input letter after then low-pass filtered device filters out high-frequency harmonic, after restoring desired be amplified
Number.To make input signal not generate serious distortion after PWM is modulated, triangular wave frequency generally takes frequency input signal
10 times or more.
Impedance matching network:
Since ultrasonic transducer is a kind of strong nonlinearity time-varying system, that characteristic of impedance under different working frequencies
Difference is very big.Therefore, it needs to carry out frequency-response analysis and impedance matching to ultrasonic transducer in audio frequency directional system, to reach
To highest efficiency of transmission and optimal acoustical quality.
As shown in fig. 6, ultrasonic transducer can be equivalent to the above electrical model.When ultrasonic transducer is far below interior
When portion's natural resonance frequency works, the electrology characteristic of energy converter is equivalent to a capacitor, referred to as direct capacitance,Mainly depend on
It is approximately constant in the geometric dimension and electrode area of sensor material.When ultrasonic transducer is in internal natural resonance frequency
Nearby when work, energy converter has very strong non-linear and time variation, and small frequency shift will lead to transducer impedance spy
The large change of property.Piezoelectric ceramic ultrasonic transducer can be equivalent to a direct capacitance and dynamic electric resistor, dynamic capacity and move
The equivalent-circuit model that state inductance series circuit is in parallel.
It the use of inductor-capacitor formula matching is since it can preferably be carried out with the value of flexible modulation inductance and capacitor
Match, so using relatively broad.Again in energy converter resonance frequency, dynamic inductance and dynamic capacityIt can ignore, by impedance
The relational expression that the principle matched can obtain between matching inductance and matching capacitance is.
In the present embodiment, D-type power amplifier driving ultrasonic transducer work is used, but since ultrasonic transducer is to hold
Property load, it is easy to generate the D class power amplifier overcurrent protection phenomenon generated by higher hamonic wave, cause system can not normal operation.It is high
Subharmonic overcurrent protection is a kind of special overpower phenomenon, completely correct in circuit design, and ordinary power test is less than volume
Under the premise of determining power, this kind of protection problem is more hidden.ZOBEL network be by with ultrasonic transducer parallel connection resistance-capacitance network,
By the lifting for compensating the perception transducer impedance always of ultrasonic transducer.
In terms of signal processing technology, main theory is according to the acoustic parametric arrays theory for being Westervelt, due to these reasons
By no Exact, approximate processing can only be carried out, cause using signal processing method diversification, have been carried out for example
There is no unified theoretical systems for the methods of square-root method, TDSB method again for DSBAM, SSBAM, square-root method, double integrator, at this
What is produced under a little methods is difficult to determine from demodulation audio signal influence factor, brings difficulty to Analysis of The Acoustic Fields.The design
It is middle theoretical using Berktay acoustic parametric arrays, and cut tiltedly for the frequency response of this theoretical existing 12dB/ octave itself
Defect compensates for the low frequency response of audio beam loudspeaker, has reached better frequency response.In terms of filtering operation, this hair
More filters have been used in bright, can preferably be restored initial audio signal, be filtered out noise.
In terms of power amplifier technology, since audio beam loudspeaker is not directly to be generated by vibrating air molecule
Audible sound, but generated indirectly by ultrasound, cause its electroacoustic efficiency lower, the audible sound energy consumption produced only accounts for whole energy
The sub-fraction of consumption, the lower AB class Linear Power Amplifier of service efficiency are difficult to meet the high-power output requirement of audio frequency directional system,
Generally use the digital switching regulator high efficiency power amplifier technology such as D class, E class, G class or T class.Further, since super refer to
The impedance variations dynamic range of tropism loudspeaker is very big, and load characteristic is mostly capacitive, and the impedance to work in supersonic range is very
It is low, it is more demanding to power amplifier driving capability, therefore level-one resistance is added in the design between power amplifier and energy converter
On the one hand anti-matching network filters out the higher hamonic wave of HF switch power amplifier itself, on the other hand constructs resonance together with energy converter
Network, so that electrical power is maximumlly applied to energy converter both ends, so that energy converter produces bigger sound pressure level.
In terms of transducer technology, as the sound-generating element of audio beam loudspeaker system, the intrinsic frequency of energy converter, band
The indexs such as width, amplitude, ultrasonic directive property directly determine the performance parameters such as output acoustic power, frequency response, the directive property of system.
Special ultrasound transducer array arrangement mode is devised in this patent, by this kind of arrangement mode, final sound wave can be with
Narrower, thinner wave beam is formed, the final effect of super directive property is had reached.
Above description is only a specific implementation of the present invention, but the protection scope of the utility model is not limited to
In this, any change or replacement expected without creative work be should be covered by the protection scope of the present invention.Cause
This, the protection scope of the utility model should be determined by the scope of protection defined in the claims.
Claims (9)
1. a kind of audio beam loudspeaker, it is characterised in that: including casing, the more than one ultrasonic transduction that is set in casing
Device, ultrasonic transducer are installed on pcb board, and pcb board is installed in casing, are also equipped with infrared sensor on the casing, when
After someone passes through, infrared sensor can give signal processing mainboard trigger signal, activate entire loudspeaker to target area broadcasting sound
Sound.
2. audio beam loudspeaker as described in claim 1, it is characterised in that: be equipped with power supply on the signal processing mainboard
Adapter, digital power amplifier, long distance signal transmission line interface terminal, volume adjustment knob, signal input port, infrared switch,
Edge shield item is wrapped up in infrared sensor, signal lamp and power switch, signal processing mainboard outside, and power supply adaptor is inserted
Enter external power supply, entire signal processing mainboard is remotely controlled by remote controller.
3. audio beam loudspeaker as described in claim 1, it is characterised in that: further include an audio input plate.
4. audio beam loudspeaker as claimed in claim 3, it is characterised in that: the audio input plate include bluetooth input,
USB port input, the input of TF RAM card.
5. audio beam loudspeaker as claimed in claim 2, it is characterised in that: be provided in the remote controller EQ by
Key, respectively Normal, Class, Jazz, Rock, Bass and POP.
6. audio beam loudspeaker as described in claim 1, it is characterised in that: ultrasonic transducer shares 139, in energy converter
Heart point line constitutes 60 ° of angle arrangements, and energy converter pin line is arranged parallel to each other.
7. audio beam loudspeaker as described in claim 1, it is characterised in that: pcb board surrounding has 6 protrusions to fix for screw
Hole location, PCB are fixed entirely through bolt.
8. audio beam loudspeaker as described in claim 1, it is characterised in that: audio beam loudspeaker is installed on desktop, wall
Face or embedded ceiling are installed on ground.
9. audio beam loudspeaker as described in claim 1, it is characterised in that: it further include thering is acoustic beam to protect sound absorption structure,
Blocking surfaces are laid with sound absorbing object.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721117794.5U CN208300016U (en) | 2017-09-02 | 2017-09-02 | A kind of audio beam loudspeaker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721117794.5U CN208300016U (en) | 2017-09-02 | 2017-09-02 | A kind of audio beam loudspeaker |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208300016U true CN208300016U (en) | 2018-12-28 |
Family
ID=64696535
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721117794.5U Active CN208300016U (en) | 2017-09-02 | 2017-09-02 | A kind of audio beam loudspeaker |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN208300016U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107708041A (en) * | 2017-09-02 | 2018-02-16 | 上海朗宴智能科技有限公司 | A kind of audio beam loudspeaker |
| CN111530722A (en) * | 2020-04-21 | 2020-08-14 | 民航成都电子技术有限责任公司 | Ultrasonic transducer, directional sound wave bird repelling system and method |
-
2017
- 2017-09-02 CN CN201721117794.5U patent/CN208300016U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107708041A (en) * | 2017-09-02 | 2018-02-16 | 上海朗宴智能科技有限公司 | A kind of audio beam loudspeaker |
| CN111530722A (en) * | 2020-04-21 | 2020-08-14 | 民航成都电子技术有限责任公司 | Ultrasonic transducer, directional sound wave bird repelling system and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107708041A (en) | A kind of audio beam loudspeaker | |
| US7564981B2 (en) | Method of adjusting linear parameters of a parametric ultrasonic signal to reduce non-linearities in decoupled audio output waves and system including same | |
| US8064627B2 (en) | Acoustic system | |
| CN101790118A (en) | Audio-frequency directional loudspeaker system and signal processing method thereof | |
| CN208300016U (en) | A kind of audio beam loudspeaker | |
| US20220053264A1 (en) | Speaker apparatus | |
| US9210509B2 (en) | System and method for directional sound transmission with a linear array of exponentially spaced loudspeakers | |
| CN109361991A (en) | A kind of more scene directional sound systems and its operation method based on DSP platform | |
| CN110381412A (en) | A kind of device that realizing directive property sounding, method and electronic equipment | |
| CN107396228A (en) | Wireless headset and its control system based on ultrasonic wave | |
| CN107509156B (en) | Tuning system | |
| US8320580B2 (en) | System and method for directional sound transmission with a linear array of exponentially spaced loudspeakers | |
| CN110784799B (en) | Sound directional transmission method and system | |
| CN101378602B (en) | Display acoustics circuit | |
| CN101111096A (en) | Combined sound frequency orienting ultrasound wave loud-speaker system | |
| CN207897145U (en) | A kind of adaptive gamut orientation loudspeaker | |
| CN210202074U (en) | Analog buzzer circuit and electronic equipment | |
| CN206532594U (en) | Electronic noise reduction device and vehicle | |
| TW595238B (en) | Feedback type active noise control circuit | |
| CN208424686U (en) | Coaxially lead the earphone of passive vibrating diaphragm technology | |
| US20200045424A1 (en) | Multi-chambered ported resonator for distributed mode and balanced mode radiator transducers | |
| CN217011167U (en) | Intelligent audio super-directional playing device | |
| CN203368720U (en) | Directive sound source system | |
| Wang et al. | Defining the parameters of truncated square-rooting DSB for parametric loudspeaker | |
| CN204422753U (en) | A kind of target strength measurement device of submarine target |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |