CN2691200Y - Digital speaker - Google Patents
Digital speaker Download PDFInfo
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- CN2691200Y CN2691200Y CN 200420044234 CN200420044234U CN2691200Y CN 2691200 Y CN2691200 Y CN 2691200Y CN 200420044234 CN200420044234 CN 200420044234 CN 200420044234 U CN200420044234 U CN 200420044234U CN 2691200 Y CN2691200 Y CN 2691200Y
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Abstract
The utility model provides a digital speaker, comprising an audio signal input circuit, a power amplification circuit, a loud-speaker for playing sound and a module for canceling noise, speaking echo and side tone of the input audio signal. The audio signal input terminal of the module for canceling noise, speaking echo and side tone is connected with the output terminal of the audio signal input circuit. The audio signal output terminal of the module for canceling noise, speaking echo and side tone is connected with the input terminal of the power amplification circuit. The output terminal of the power amplification circuit is connected with the loud-speaker. The module for canceling noise, speaking echo and side tone is an integrated circuit FM1073. The utility model can effectively cancel noise, speaking echo and side tone and can be applied to high-fidelity home theater, PC network direct communication and teleconference. The digital speaker can effectively cancel speaking echo even if both speakers are hand free.
Description
[technical field]
The utility model relates to a kind of sound equipment, relates in particular to a kind of digital audio amplifier, is widely used in long-distance education on home audio, network telephone conference, online game and the line.
[background technology]
Along with the raising of living standards of the people, can many people particularly Fanciers the perfect distortionless also requirement of original sound be bordering on harshness to audio-frequency power amplifier.The power amplifier of simulation is through decades development, and technology is quite ripe, has almost arrived the limit in this respect, and tonequality can not show a candle to digital, so the digital power amplifier of high efficiency, low distortion will replace.Yet the digital audio amplifier of domestic production at present can only be adapted to the effect as general playback music, aspect computer applications, can't be applied to the direct communication of network owing to having very big echo and noise.Thereby the huge commercial opportunities of PC industry have been lost.Simultaneously along with market competition is growing more intense, the information requirement that people are growing, as car handsfree, remote web teaching, on e-learning and the enterprise's line training etc. be applied in the live and work by people more and more, these are used all needs the high-quality sound system of a cover, will transmit next voice reproduction or the voice that microphone picks up are sent to the recipient from far-end.And be used at present the conversation hand free device of network or phone both at home and abroad, and have all that echo is big, a howling, defective that noise is big, can't satisfy the requirement of above-mentioned occasion.
[summary of the invention]
Main purpose of the present utility model is exactly for the big shortcoming of the noise that solves prior art, echo and sidetone, a kind of digital audio amplifier is provided, make when receiving the voice that far-end transmits can abate the noise, talk echo and sidetone, can be applicable to the speech play of aspects such as computer applications, videoconference or the Web-based instruction.
Secondary objective of the present utility model provides a kind of digital audio amplifier, make when voice transfer is gone out can abate the noise, talk echo and sidetone.
For achieving the above object, the utility model proposes a kind of digital audio amplifier, comprise audio signal input circuit, power amplifier and the loud speaker that is used to play sound, also comprise the audio signal that is used for input abate the noise, the converse module U7 of echo and sidetone, the audio signal input end of described module U7 connects the output of audio signal input circuit, the audio signal output end of described module U7 connects the input of power amplifier, and the output of described power amplifier connects loud speaker.
In order to make the better effects if that abates the noise with talk echo and sidetone, when transferring out, the signal that microphone is picked up just abates the noise and the processing of echo and sidetone, so the utility model also comprises microphone signal input circuit and microphone signal output circuit, the microphone signal input pin of described microphone signal input circuit and module U7 links to each other, and the microphone signal output pin of module U7 exports the microphone signal output circuit to.
Described abate the noise and echo and sidetone module U7 are integrated circuit FM1073.As Fig. 2, shown in 3, integrated circuit FM1073 is used for carrying out following processing from the audio signal of far-end input and the voice signal of importing from microphone: the voice signal that microphone picks up (speech of near-end and the speech of far-end go out the echo that is coupled to form by microphone in the loud speaker playback) enters with the form of difference input, amplify after half-duplex detects, after high pass filter and preemphasis are handled, analog-to-digital conversion becomes 16 speech data, noise suppressed is handled and echo is eliminated by carrying out after the microphone gain adjustment, and with the signal of circuit input relatively, remove, obtain the voice data of near-end; Carry out fast fourier transform and inverse transformation then, carry out echo cancellation process once more at frequency domain; Carry out microphone volume control at last, after filtering of postemphasising (promptly removing unwanted signal) and the digital-to-analogue conversion with signal from the single-ended output of line output difference.The audio signal of far-end is single-ended or difference input from line input, through high-pass filtering and preemphasis, become 16 speech datas after the analog-to-digital conversion process, after handling, anti-sidetone is divided into two paths of data, one the tunnel send echo cancellation process, and another road is amplified after digital-to-analogue conversion and increased the weight of processing, exports from loud speaker output difference, send digital power amplifier to amplify, promote the loud speaker sounding.Filtration module among the integrated circuit FM1073 comprises half-duplex detection, high pass filter and preemphasis filter.
So the beneficial effects of the utility model are: 1) by adopting the non-linear wave filter technology of adaptive step subband (Adaptive step size sub-band non-linear filter (AS3NLF) technology) matrix microphone beam collective noise compacting passage control (AMBIN channel control), can adjust inhibiting factor fast electric-wave filter (Adjustable suppression factor post filter), former noise smoothing technology (Non-artificialnoise smoothe), vibrating sensor (Vibration sensor) and digital power amplifier are combined into one, wherein utilize integrated circuit FM1073 that the signal from the far-end input is carried out the de-noising sound, anti-sidetone and disappearing after the echo processing reduces this digital audio amplifier noise and echo when playing greatly.2) by utilize integrated circuit FM1073 to the signal from microphone input carry out the de-noising sound, after the disappear echo and the Filtering Processing of postemphasising, this digital audio amplifier picks up at a distance to hands-free system under the situation of voice, make voice when sending, carry out noise signals filtering and echo cancellation process, so that the recipient can receive high-quality voice signal, even both sides under hands-free situation, also can effectively eliminate the conversation echo.So the utility model can be applied to high-fidelity home theater, the direct communication of PC network and videoconference.
Feature of the present utility model and advantage will be elaborated in conjunction with the accompanying drawings by embodiment.
[description of drawings]
Fig. 1 represents functional-block diagram of the present utility model;
Fig. 2 represents the module principle figure of the utility model integrated circuit FM1073;
Fig. 3 represents the filter module schematic diagram among the utility model integrated circuit FM1073
Fig. 4 represents the structure chart of the utility model integrated circuit FM1073;
Fig. 5 represents the circuit diagram of first embodiment of the present utility model;
Fig. 6 represents the block diagram of second embodiment of the present utility model;
Fig. 7 a represents one of parameter testing flow chart of the present utility model;
Fig. 7 b represents two of parameter testing flow chart of the present utility model.
[embodiment]
Be illustrated in figure 1 as block diagram of the present utility model, comprise that circuit is input to loud speaker output and microphone is input to circuit output.By the audio signal order of circuit input by the audio signal input circuit, abate the noise and echo module U7 and power amplifier, output to loud speaker at last; Voice signal by the microphone input passes through microphone signal input circuit, module U7 and microphone signal output circuit in proper order.Described module U7 is integrated circuit FM1073.Described module U7 also can be other modules that include noise reduction and eliminate functions such as echo.
Be illustrated in figure 4 as the structure chart of integrated circuit FM1073, comprise 16 position digital signal processing modules, be equivalent to DSP acoustic processing engine, 4 passage analog-to-digital conversion, 2 passage digital-to-analogue conversions, the 40KB ROM that contains the DSP firmware and the 16KB RAM of 86MIPS.Have three microphone inputs, two differential line inputs, circuit output and loud speaker output.Integrated circuit FM1073 has the 8K/11K sampling rate, supports the 120-3400Hz/165-4500Hz bandwidth, and signal to noise ratio reaches 78dB, reduces radio frequency interference and white noise.Programmable-gain input and output amplifier adapts to the different sensitivity microphone, circuit input and output level.The noise compacting reaches 18dB, applicable to noisy automotive environment.Nonlinear echo is eliminated, and is suitable for the overload of compact horn when high-power.Echo elimination reaches 52dB (1 microphone) during full duplex, and 65 (2 microphones) provide voice clearly.Sidetone is eliminated 35dB.Microphone and loud speaker 32 stages of digital volumes control :-12-+18dB.Default work/plug-in EEPROM (parameter is programmed again)/SHI or three kinds of working methods of UART microprocessor control.The CHI bus is supported μ-Law and linear PCM pattern, flexible and digital communication equipment interface.
The microphone that when practical application, can not connect microphone or connection suitable quantity according to situation about using.
Be illustrated in figure 5 as first embodiment of the present utility model, described audio signal input circuit comprises audio analog signals input interface and the low pass filter that order links to each other, and the output of described low pass filter is connected with the audio signal input end of described module U7; Described microphone signal output circuit is the microphone signal analog output circuit.Described module U7 is integrated circuit FM1073, the microphone MICO pickoff signals of described digital acoustics enters internal microphone wave beam collective noise compacting channel controller from integrated circuit FM1073 the 37th pin after the low-pass filtering that the 19 resistance R the 19, the 12 capacitor C 12 is formed, after filtering, noise reduction, disappear echo and sidetone processing, enter PC MIC-IN through the 47th pin Line-OUT of integrated circuit FM1073 and send; In like manner, the signal that sends from PC network or telephone wire is through the 45 resistance R the 45, the 27 capacitor C 27 low-pass filtering, be coupled to integrated circuit FM1073 the 43rd, 44 pin through the 25 capacitor C the 25, the 29 capacitor C 29, through inner low-pass filtering, preemphasis, anti-sidetone, echo disappears, after the Filtering Processing of postemphasising, the 1st, 2 pin output by integrated circuit FM1073, enter the tenth capacitor C 10 respectively and be coupled to power amplifier U12 the 5th, 3 pin, promote loud speaker LS1, LS2 from the output of power amplifier U12 the 1st, 7 pin then and realize the electroacoustic signal conversion.During application, be inserted into PC SPK-OUT audio output interface and MIC-IN interface respectively, thereby can realize the noise reduction echo that disappears, the online hand-free call of remote pickoff signals.
Be illustrated in figure 6 as second embodiment of the present utility model, different with first embodiment is that described audio signal input circuit comprises audio digital signals input interface and the audio digital signals treatment circuit that order links to each other, and described audio digital signals treatment circuit links to each other with described integrated circuit FM1073; Described microphone signal output circuit is the microphone signal digital output circuit, the microphone signal output pin of described integrated circuit FM1073 links to each other with the audio digital signals treatment circuit, exports the microphone signal digital output circuit after the audio digital signals processing circuit processes to.In view of USB interface extensively, use expediently, described audio digital signals input interface and described microphone signal digital output circuit are designed to USB interface, described audio digital signals treatment circuit is integrated circuit CM108, its audio digital signals importation comprises the USB interface that order links to each other, ISO exports processing unit, the D/A converting circuit and first gain circuitry, its microphone signal output comprises second gain circuitry that order links to each other, analog to digital conversion circuit, ISO input processing unit and USB interface, described first gain circuitry links to each other with Lin-in line or the Lin-out line of described integrated circuit FM1073 respectively with second gain circuitry, the signal of described USB interface response USB interface input, for integrated circuit FM1073, changed MIC-in line and the SPK-out line plug of the integrated circuit FM1073 among the embodiment one into USB plug.During application, the USB plug of LXH/B digital audio amplifier is inserted into the USB socket of PC computer, thereby realizes noise reduction, the online hand-free call of disappear echo and sidetone, remote pickoff signals.
Be depicted as the parameter testing flow chart of integrated circuit FM1073 in the utility model as Fig. 7 a-7b, the test of signaling interface basic parameter, a fixed-audio signal is sent with computer in place at distance microphone 0.3-0.6 rice, measure the output signal size (peak-to-peak value) of integrated circuit FM1073 the 37th pin (MIC0_P) pin microphone, signal amplitude is taken advantage of 2, as the reference that microphone programmable-gain value is set.Output is the level requirement of mobile phone or other equipment microphones or circuit input according to circuit, and the volume of microphone is set.Dial a fixed number, as 1860 etc., the measurement circuitry input is mobile phone or other device speaker or circuit output level, and as the reference that circuit input programmable-gain value is set, the level requirement according to loud speaker output is provided with speaker volume.
Echo parameter is adjusted, and plays one section speech and imports from circuit, if echo is a whole section sentence, just should disconnect microphone, sees if there is echo, if also have, checks with being connected of mobile phone whether problem is arranged.The echo that does not have reconnects microphone.Measure and calculate microphone and circuit input through the amplitude behind the programmable gain amplifier, the ratio of getting both is multiplied by coefficient (1.8/2), eliminates reference gain as echo.Respectively at small-signal (far-end little sound speech), measure echo then,, illustrate that then the loop has problem or microphone saturated if having.Whether test has echo during signal amplitude (normal speech) under the normal operating position, and the words that have are adjusted linear echo and eliminated parameter.In large-signal (under the situation that simulation speaks aloud), measure echo at last, adjust nonlinear echo and eliminate parameter.
The anti-sidetone parameter adjustment is sent an audio signal from the microphone input, the amplitude of measurement circuitry output and circuit input, and the ratio of getting both is multiplied by the reference gain that coefficient (2/1.6) is eliminated as sidetone.Adjust relevant parameter then.
The noise suppressed parameter adjustment checks at first when talking simultaneously on both sides whether noise is arranged, and the words that have then reduce noise gain.Listen the situation whether noise bounce is arranged then, the words that have then promote noise gain, after debugging is good, as requested, noise suppressed high value and ground level value are set respectively.
The full duplex parameter adjustment checks earlier whether microphone is saturated, and the saturated meeting of microphone is eliminated by echo and full-duplex preformance descends.If system uses a microphone then as long as adjust 1 microphone full duplex parameter, during two microphones, also will carry out 2 microphone full duplex parameter adjustments then.After adjustment is finished, also to carry out the test of echo performance.
The utility model is mainly used in network telephone conference, long-distance education, online directly communication (IM).Language transmission spreads to online game and home audio, home theater etc. fast on the line.When as the direct communication of network (IM), development potentiality is huge, and according to statistics, global computer mainboard shipment amount was expected to be more than 100,004,000 ten thousand covers in 2004, and the future net has six million peoples to use IM at work.Will be to this numeral in 2005 above 200,015,000, AOL and Yahoo have released office IM version.Measurable thus, every PC will need a hands-free digital audio amplifier to carry out voice communication, and will there be the demand of several hundred million covers in the following 1 year whole world, and market potential is huge.
Claims (10)
1. digital audio amplifier, comprise audio signal input circuit, power amplifier and the loud speaker that is used to play sound, it is characterized in that: also comprise the audio signal that is used for input abate the noise, the converse module (U7) of echo and sidetone, the audio signal input end of described module (U7) connects the output of audio signal input circuit, the audio signal output end of described module (U7) connects the input of power amplifier, and the output of described power amplifier connects loud speaker.
2. digital sound as claimed in claim 1 is characterized in that: described abate the noise and the module (U7) of echo and sidetone is integrated circuit EM1073.
3. digital audio amplifier as claimed in claim 1 or 2, it is characterized in that: also comprise microphone signal input circuit and microphone signal output circuit, described microphone signal input circuit links to each other with the microphone signal input pin of module (U7), and the microphone signal output pin of module (U7) exports the microphone signal output circuit to.
4. digital audio amplifier as claimed in claim 1 or 2, it is characterized in that: described audio signal input circuit comprises audio analog signals input interface and the low pass filter that order links to each other, and the output of described low pass filter is connected with the audio signal input end of described module (U7).
5. digital audio amplifier as claimed in claim 3, it is characterized in that: described audio signal input circuit comprises audio analog signals input interface and the low pass filter that order links to each other, and the output of described low pass filter is connected with the audio signal input end of described module (U7); Described microphone signal output circuit is the microphone signal analog output circuit.
6. digital audio amplifier as claimed in claim 1 or 2, it is characterized in that: described audio signal input circuit comprises audio digital signals input interface and the audio digital signals treatment circuit that order links to each other, and described audio digital signals treatment circuit links to each other with described module (U7).
7. digital audio amplifier as claimed in claim 3, it is characterized in that: described audio signal input circuit comprises audio digital signals input interface and the audio digital signals treatment circuit that order links to each other, and described audio digital signals treatment circuit links to each other with described module (U7); Described microphone signal output circuit is the microphone signal digital output circuit, the microphone signal output pin of described module (U7) links to each other with the audio digital signals treatment circuit, exports the microphone signal digital output circuit after the audio digital signals processing circuit processes to.
8. digital audio amplifier as claimed in claim 6, it is characterized in that: described audio digital signals input interface is a USB interface, described audio digital signals treatment circuit comprises that USB interface, ISO that order links to each other export processing unit, D/A converting circuit and first gain circuitry, described first gain circuitry links to each other with described module (U7), the signal of described USB interface response USB interface input.
9. digital audio amplifier as claimed in claim 7, it is characterized in that: described audio digital signals input interface and described microphone signal digital output circuit are USB interface, the audio digital signals importation of described audio digital signals treatment circuit comprises the USB interface that order links to each other, ISO exports processing unit, the interface logic processing unit, the D/A converting circuit and first gain circuitry, the microphone signal output of described audio digital signals treatment circuit comprises second gain circuitry that order links to each other, analog to digital conversion circuit, ISO input processing unit and USB interface, described first gain circuitry links to each other with described module (U7) respectively with second gain circuitry, and described USB interface links to each other with USB interface.
10. digital audio amplifier as claimed in claim 3 is characterized in that: described microphone signal input circuit is 3 the tunnel, respectively the microphone signal input pin of link block (U7).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420044234 CN2691200Y (en) | 2004-04-01 | 2004-04-01 | Digital speaker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420044234 CN2691200Y (en) | 2004-04-01 | 2004-04-01 | Digital speaker |
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| Publication Number | Publication Date |
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| CN2691200Y true CN2691200Y (en) | 2005-04-06 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 200420044234 Expired - Fee Related CN2691200Y (en) | 2004-04-01 | 2004-04-01 | Digital speaker |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102497613A (en) * | 2011-11-30 | 2012-06-13 | 江苏奇异点网络有限公司 | Dual-channel real-time voice output method for amplifying classroom voices |
| CN102572644A (en) * | 2010-12-29 | 2012-07-11 | 上海博泰悦臻电子设备制造有限公司 | Microphone device |
| CN101379870B (en) * | 2006-01-31 | 2013-03-20 | 雅马哈株式会社 | Voice conference device |
| CN103621050A (en) * | 2011-04-28 | 2014-03-05 | 株式会社理光 | Conference device |
| CN104303521A (en) * | 2013-01-26 | 2015-01-21 | 奥迪股份公司 | Motor vehicle and microphone for a microphone arrangement in the motor vehicle |
| CN104780481A (en) * | 2015-03-31 | 2015-07-15 | 袁晶 | Microphone device and sound system |
| CN108055610A (en) * | 2017-03-31 | 2018-05-18 | 佳禾智能科技股份有限公司 | Intelligent sound box |
| CN109413522A (en) * | 2018-11-08 | 2019-03-01 | 深圳市云威物联科技有限公司 | Audio signal processing method, audio-signal processing apparatus and electronic equipment |
| CN110289025A (en) * | 2019-07-29 | 2019-09-27 | 东莞市居胜电子有限公司 | A kind of multi-medium video-signal sound system |
| CN112086101A (en) * | 2020-08-19 | 2020-12-15 | 广州亚美智造科技有限公司 | Noise reduction circuit, voice recognition module and electronic equipment |
| CN112653966A (en) * | 2020-12-24 | 2021-04-13 | 昆腾微电子股份有限公司 | Earphone interface circuit and electronic equipment |
| CN115442711A (en) * | 2022-08-10 | 2022-12-06 | 星宸科技股份有限公司 | Audio processing device and method with echo cancellation mechanism |
| TWI849477B (en) * | 2022-08-16 | 2024-07-21 | 大陸商星宸科技股份有限公司 | Audio processing apparatus and method having echo canceling mechanism |
-
2004
- 2004-04-01 CN CN 200420044234 patent/CN2691200Y/en not_active Expired - Fee Related
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101379870B (en) * | 2006-01-31 | 2013-03-20 | 雅马哈株式会社 | Voice conference device |
| CN102572644A (en) * | 2010-12-29 | 2012-07-11 | 上海博泰悦臻电子设备制造有限公司 | Microphone device |
| CN102572644B (en) * | 2010-12-29 | 2015-07-15 | 上海博泰悦臻电子设备制造有限公司 | Microphone device |
| CN103621050B (en) * | 2011-04-28 | 2016-08-17 | 株式会社理光 | Conference facility |
| CN103621050A (en) * | 2011-04-28 | 2014-03-05 | 株式会社理光 | Conference device |
| CN102497613A (en) * | 2011-11-30 | 2012-06-13 | 江苏奇异点网络有限公司 | Dual-channel real-time voice output method for amplifying classroom voices |
| CN104303521B (en) * | 2013-01-26 | 2017-04-26 | 奥迪股份公司 | Motor vehicle and microphone for a microphone arrangement in the motor vehicle |
| CN104303521A (en) * | 2013-01-26 | 2015-01-21 | 奥迪股份公司 | Motor vehicle and microphone for a microphone arrangement in the motor vehicle |
| CN104780481A (en) * | 2015-03-31 | 2015-07-15 | 袁晶 | Microphone device and sound system |
| CN108055610A (en) * | 2017-03-31 | 2018-05-18 | 佳禾智能科技股份有限公司 | Intelligent sound box |
| CN109413522A (en) * | 2018-11-08 | 2019-03-01 | 深圳市云威物联科技有限公司 | Audio signal processing method, audio-signal processing apparatus and electronic equipment |
| CN110289025A (en) * | 2019-07-29 | 2019-09-27 | 东莞市居胜电子有限公司 | A kind of multi-medium video-signal sound system |
| CN112086101A (en) * | 2020-08-19 | 2020-12-15 | 广州亚美智造科技有限公司 | Noise reduction circuit, voice recognition module and electronic equipment |
| CN112653966A (en) * | 2020-12-24 | 2021-04-13 | 昆腾微电子股份有限公司 | Earphone interface circuit and electronic equipment |
| CN115442711A (en) * | 2022-08-10 | 2022-12-06 | 星宸科技股份有限公司 | Audio processing device and method with echo cancellation mechanism |
| TWI849477B (en) * | 2022-08-16 | 2024-07-21 | 大陸商星宸科技股份有限公司 | Audio processing apparatus and method having echo canceling mechanism |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20050406 Termination date: 20130401 |