CN100477510C - Apparatus and method for automatically regulating microphone input level of portable terminal - Google Patents
Apparatus and method for automatically regulating microphone input level of portable terminal Download PDFInfo
- Publication number
- CN100477510C CN100477510C CNB2004100781981A CN200410078198A CN100477510C CN 100477510 C CN100477510 C CN 100477510C CN B2004100781981 A CNB2004100781981 A CN B2004100781981A CN 200410078198 A CN200410078198 A CN 200410078198A CN 100477510 C CN100477510 C CN 100477510C
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- China
- Prior art keywords
- signal
- microphone
- level
- bias voltage
- portable terminal
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
- H04M1/6008—Substation equipment, e.g. for use by subscribers including speech amplifiers in the transmitter circuit
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/02—Constructional features of telephone sets
- H04M1/03—Constructional features of telephone transmitters or receivers, e.g. telephone hand-sets
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
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- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Circuit For Audible Band Transducer (AREA)
- Control Of Amplification And Gain Control (AREA)
- Telephone Function (AREA)
Abstract
The invention relates to an apparatus and method for automatically regulating microphone input level of portable terminal. The invention includes follow parts: Microphone for transferring analog audio-stage signal accessing to the portable terminal into electrical signal to input; encoding-decoding portion for amplifying the analog audio-stage signal from the microphone in predetermined amplification ratio, and transfer the same into digital audio-stage signal to output; external amplifier which receiving the audio-stage signal amplified by the encoding-decoding portion, and amplifying the same in predetermined amplification ratio and re-connecting to the encoding-decoding portion; input level regulation portion for controlling the biasing voltage of the microphone according to the average signal level which has been amplified and output by the external amplifier. The audio-stage signal input level of the portable terminal is automatically regulated to a certain level, so that the amplifier can amplify the same in fixed amplification ratio thereby simplifying design and constitution for circuit, and improving talking sensitivity and enhancing production reliability.
Description
Technical field
The present invention relates to adjust automatically the voice-grade sig-nal-conditioning unit and the method for portable terminal device microphone, the microphone input level automatic regulating apparatus and the method that particularly relate to a kind of portable terminal device, it adjusts the bias voltage of microphone portion, automatically control audio level signal input sensitivity makes the voice-grade signal level relative fixed of amplifying and exporting.
Background of invention
When moving freely in the service area (SERVICE AREA) that mobile communication portable terminal device (MS:MOBILE STATION) is used for forming in a plurality of base stations (BS:BASE STATION) by the mobile communication system that networks, under the switching (SWITCHING) of mobile switching centre (MSC:MOBILE SWITCHING CENTER) and control (CONTROL) whenever and wherever possible with the instant wireless connections of the other side and communicate, it is a kind of most advanced and sophisticated Wireless Telecom Equipment, has the advantage that can directly be carried and be communicated by the individual.
As above the portable terminal device that is protected of mobility can carry out mobile communication when the walking by the individual, or communication when riding public transportation means moves, when taking the described vehicles and move, particularly communicate for on-stream, can add other speaker phone functionality.
When using described portable terminal device itself, the distance of mouth and microphone portion is closer, and the variable in distance amplitude is little, the voice-grade signal level relative fixed of input.But when adding the speaker phone functionality use, the distance between microphone portion and the mouth is fixing, and the variable in distance amplitude is big, has the problem of the voice-grade signal magnitude vary within wide limits of the described microphone of access portion.
Therefore, need a kind of technology of exploitation, even when the size variation amplitude of the voice-grade signal of the microphone portion that inserts portable terminal device is big, also can be enlarged into certain level and exports.
The microphone gain adjusting device of portable terminal device of the prior art is described with reference to the accompanying drawings.
Fig. 1 is the microphone gain adjusting device function constitution map of portable terminal device of the prior art, and it is used to illustrate prior art.
At first, the microphone gain adjusting device of the portable terminal device under the prior art is described with reference to Fig. 1.Be access in the coder portion 20 of the portable terminal modulator-demodulator (MSM:MOBILE STATIONMODEM) of control portable terminal device from the voice-grade signal of microphone portion 10 outputs that constitute with the portable terminal device one and be used to import the voice-grade signal.
Described microphone portion 10 becomes the voice-grade conversion of signals of access the signal of telecommunication to export according to the microphone bias voltage that inserts from coder portion 20.
20 signals of telecommunication that insert from microphone portion 10 of described coder portion are imported the 1st enlarging section 30, magnification ratio that fixedly installs according to described the 1st enlarging section 30 or gain (GAIN) are amplified and are exported, amplify through described the 1st enlarging section 30 and the signal of output is transfused to outside enlarging section 40, amplify according to magnification ratio that fixedly installs or gain in described outside enlarging section 40 and export.
Amplified and the signal of output is access in the 2nd enlarging section 50 that constitutes with described coder portion 20 one the signal that amplifies input according to the magnification ratio that fixedly installs in described the 2nd enlarging section 50 line output of going forward side by side by described outside enlarging section 40.
Simulation (ANALOG) signal of telecommunication through described the 2nd enlarging section 50 amplifications and output is converted to numeral (DIGITAL) signal of telecommunication and output by Analog to Digital Converter section 60.
In the prior art, through the 1st enlarging section 30, amplify and output by outside enlarging section 40 and the 2nd enlarging section 50 the voice-grade signal of input microphone portion 10 for the microphone gain adjusting device of portable terminal device, and described each enlarging section has been provided with fixing magnification ratio and gain.
When the size of the voice-grade signal of the described microphone of input portion 10 changed, the signal of telecommunication of level had been amplified in output by fixing magnification ratio.
If imported the voice-grade signal under the state near described microphone portion 10, though magnification ratio is identical, incoming level is big, so be enlarged into high level and output; If imported the voice-grade signal under the state away from microphone portion 10, though magnification ratio is identical, incoming level is little, so be enlarged into than low level and output.
That is, because the magnification ratio of each enlarging section (30,40,50) fixes, so exist size variation because of input voice-grade signal to cause the big problem of signal level variation of amplifying and exporting.
Summary of the invention
The object of the present invention is to provide a kind of microphone input level automatic regulating apparatus and method of portable terminal device, it is controlled automatically, so that the voice-grade signal of microphone portion inserts the portable terminal device coder portion of amplifying input voice-grade signal and output according to fixing magnification ratio with certain incoming level.
For achieving the above object, feature of the present invention is to comprise following several sections: microphone portion, and it is the analogue audio frequency level conversion of signals that inserts portable terminal device that the signal of telecommunication is imported; Coder portion, it amplifies the signal of telecommunication that inserts from described microphone portion by the magnification ratio that is provided with, and is converted to digital electric signal and exports; Outside enlarging section, it inserts the signal of telecommunication that described coder portion amplifies, and amplifies and inserts described coder portion again according to the magnification ratio that is provided with; The incoming level adjustment part, it carries out smoothing processing to the signal that amplifies through described outside enlarging section and export, the output average value signal, control the bias voltage of described microphone portion, if described average value signal is higher than fiduciary level, then control to reduce the bias voltage of microphone portion,, then control to improve the bias voltage of microphone portion if described average value signal is lower than fiduciary level; Wherein, described incoming level adjustment part comprises: partes glabra, and the signal that its input is amplified and exported through described outside enlarging section carries out smoothing processing, the output average value signal; Amplify bias voltage portion, it is provided with from the bias level of the signal of described partes glabra output; Amplifier, its is according to the average value signal that inserts from described amplification bias voltage portion, adjusts the bias voltage that also output inserts described microphone portion.
For achieving the above object, another feature of the present invention is to comprise following several steps: input step, and when having imported the voice-grade signal by microphone portion, portable terminal device carries out smoothing processing, obtains average value signal; Comparison step, the average value signal that described input step is obtained and the fiduciary level of setting compare; Set-up procedure if described comparison step judged result is that mean value is lower than fiduciary level, then improves microphone bias voltage, if be higher than reference level, then reduces microphone bias voltage.
As above the microphone input level automatic regulating apparatus of the portable terminal device of the present invention of Gou Chenging and method have following result of use, promptly, it can be adjusted automatically, if the voice-grade signal inserts with low level, then improve the sensitivity of microphone portion, with the high level input, if the voice-grade signal inserts with high level, then reduce the sensitivity of microphone portion, import with low level.In the present invention, the incoming level of voice-grade signal is adjusted into certain level by microphone portion, so the enlarging section can be provided with fixing magnification ratio, thereby has simplified the design and the formation of circuit.In addition, the level that use the present invention has eliminated the voice-grade signal that takes place because of variable in distance between the microphone portion of portable terminal device and the mouth changes, thereby has improved close-talking sensitivity, has increased reliability of products.
Description of drawings
Fig. 1 is the microphone gain adjusting device function constitution map of the portable terminal device of prior art;
Fig. 2 is the microphone input level automatic regulating apparatus function constitution map of portable terminal device of the present invention;
Fig. 3 is the microphone input level automatic adjusting method flow chart of portable terminal device of the present invention.
The symbol description of accompanying drawing major part:
100: microphone portion 110: coder portion
The enlarging section 130 in 120: the 1: outside enlarging section
The enlarging section 150 in 140: the 2: Analog to Digital Converter section
160: incoming level adjustment part 162: amplifier
164: amplify bias voltage portion 166: partes glabra
Embodiment
The microphone input level automatic regulating apparatus and the method thereof of portable terminal device of the present invention are described with reference to the accompanying drawings.
Fig. 2 is the microphone input level automatic regulating apparatus function constitution map of portable terminal device of the present invention, and Fig. 3 is the microphone input level automatic adjusting method flow chart of portable terminal device of the present invention, and they all are used to illustrate the present invention.
At first, the microphone input level automatic regulating apparatus of portable terminal device of the present invention is described with reference to Fig. 2.It is by microphone portion 100, coder portion 110, and outside enlarging section 130 and incoming level adjustment part 160 constitute.Wherein:
The analog electrical signal that inserts from described microphone portion 100 amplifies according to magnification ratio that is provided with or gain in coder portion 110, is converted into digital electric signal and exports.Coder portion 110 specifically comprises following several sections: the 1st enlarging section 120, and it adjusts the level (LEVEL) of described input electrical signal according to the magnification ratio that fixedly installs, and it is outputed to outside enlarging section 130; The 2nd enlarging section 140, it is according to the level of the magnification ratio adjustment that fixedly installs through the signal of telecommunication of 130 amplifications of outside enlarging section and access, the line output of going forward side by side; Analog to Digital Converter section 150, it is converted to digital electric signal and output to the analog electrical signal that inserts from described the 2nd enlarging section 140.
The analog electrical signal that amplifies through described coder portion 110 is inserted in outside enlarging section 130, amplifies according to the magnification ratio that fixedly installs, and again it is inserted described coder portion 110.
Incoming level adjustment part 160 is according to amplifying through described outside enlarging section 130 and the average level of the signal of output, controls the bias voltage of described microphone portion 100.Incoming level adjustment part 160 specifically comprises following several sections: partes glabra 166, it is made of block capacitor and resistance and the capacitor of obtaining the input signal average value signal, carry out smoothing processing after importing the signal of described outside enlarging section, the output average value signal; Amplify bias voltage portion 164, it utilizes the resistance series connection to constitute, and inserts bias voltage to the average value signal that inserts from described partes glabra 166, is provided with from the bias level of the signal of described partes glabra output; Amplifier 162, its is according to the signal that inserts from described amplification bias voltage portion 164, adjustment is from the microphone bias voltage level of described coder portion 110 outputs, output to described microphone portion 100 with the form of bias voltage, its is according to the average value signal that inserts from described amplification bias voltage portion 164, adjusts the bias voltage that also output inserts described microphone portion 100.
With reference to the accompanying drawings, describe the microphone input level automatic regulating apparatus of the portable terminal device of the present invention that as above constitutes in detail.
After the voice-grade signal is input to the microphone portion 100 of described portable terminal device, described microphone portion 100 exports shock wave (SEISMICWAVE) voice-grade conversion of signals according to the microphone bias voltage (MIC BIAS) that inserts from coder portion 110 for the voice-grade signal of telecommunication.
Described microphone portion 100 has following inherent characteristic, that is, if the microphone bias voltage height that inserts from described coder portion 110, the output level height of the voice-grade signal of telecommunication then, if described microphone bias voltage is low, then the output level of the voice-grade signal of telecommunication is low.
The technology of the present invention is utilized the as above inherent characteristic of microphone portion 100, if the voice-grade signal level of input is low, then improves microphone bias voltage, so that the output high level voice-grade signal of telecommunication; If the voice-grade signal level height of input then reduces described microphone bias voltage, so that the voice-grade signal of telecommunication of output low level.
Be access in the 1st enlarging section 120 of coder portion 110 from the voice-grade signal of telecommunication of described microphone portion 100 outputs, the voice-grade signal of telecommunication of (AMPLIFYING) input is amplified according to magnification ratio that fixedly installs or gain in described the 1st enlarging section 120, outputs it to described outside enlarging section 130.
Amplify from the voice-grade signal of telecommunication of described the 1st enlarging section 100 inputs according to magnification ratio that fixedly installs or gain described outside enlarging section 130, with its 2nd enlarging section 140 that outputs to described coder portion 110, inserts described incoming level adjustment part 160 simultaneously.
The voice-grade signal of telecommunication that inserts from described outside enlarging section 130 is amplified in described the 2nd enlarging section 140 according to the gain that fixedly installs, it is outputed to Analog to Digital Converter section 150, and described Analog to Digital Converter section 150 is the analogue audio frequency level electrical signal conversion of input that the digital audio level signal of telecommunication is exported.
In addition, the signal of exporting and insert described incoming level enlarging section 160 from described outside enlarging section 130 is access in described partes glabra 166, described partes glabra 166 utilizes capacitor to cut off the direct current composition of the voice-grade signal of telecommunication through amplifying input, utilization obtains the average value signal and the output of the voice-grade signal of telecommunication by the smoothing function that resistance and capacitor form.
From the average value signal of described partes glabra 166 outputs is the voice-grade electrical signal conversion with the Alternating Component input that the direct current composition is exported.
As above bias voltage and output have been added as the direct current composition of mean value by described amplification bias voltage portion 164 from partes glabra 166 output.The average value signal that has been added bias voltage by described amplification bias voltage portion 164 inserts the base stage (B:BASE) of the amplifier 162 that is made of PNP transistor (TR:TRANSISTOR).
The described amplifier 162 that is made of the PNP transistor has following inherent characteristic, promptly, if its base terminal inserts low level voltage, then pro rata the voltage signal that inserts emitter-base bandgap grading (E:EMITTER) terminal is zoomed into the voltage signal of high level, output to collector electrode (C:COLLECTOR) terminal with the voltage that inserts described base terminal; If described base terminal has inserted the voltage of high level, then amplify the voltage that inserts described emitter-base bandgap grading terminal according to low level, output to described collector terminal.
The voltage signal that inserts the amplifier 162 emitter-base bandgap grading terminals of described incoming level adjustment part 160 is the microphone bias voltage signal from 110 outputs of described coder portion, and the voltage signal that outputs to the collector terminal of described amplifier 162 is the microphone bias voltage signal that inserts described microphone portion 100.
That is, if it is low to import the level of voice-grade signal of described microphone portion 100, the microphone bias voltage signal of then described incoming level adjustment part 160 output high level, thereby to the voice-grade signal of telecommunication of described coder portion 110 output high level; If imported the voice-grade signal of high level to described microphone portion 100, the microphone bias voltage signal of then described incoming level adjustment part 160 output low levels, thereby to the voice-grade signal of telecommunication of described coder portion 110 output low levels.
Therefore, described incoming level adjustment part 160 is adjusted automatically and is controlled, when talking near the microphone portion 100 of portable terminal device, make the low level voice-grade signal of telecommunication output to described coder portion 120 automatically, when under state, talking away from described microphone portion, make the voice-grade signal of telecommunication of high level output to described coder portion 120 automatically, thereby have the advantage that makes the other side be easy to listen to.
Below with reference to Fig. 3, the microphone input level automatic adjusting method of portable terminal device of the present invention is described.It comprises input step, comparison step and set-up procedure.
Input step is when microphone portion 100 has imported the voice-grade signal, and portable terminal device carries out smoothing processing, obtains average value signal.This step specifically comprises following several steps: step S100, judges whether imported the voice-grade signal in the microphone portion 100; Step S110 if described step S100 judges thinks and has imported the voice-grade signal in the microphone portion 100, then carries out smoothing processing, draws average value signal.
Comparison step S120 is the fiduciary level comparison to average value signal that draws among the described step S110 and setting, and judgement is a height or low.
Set-up procedure is if judged result is that mean value is lower than fiduciary level in described input step, then improves microphone bias voltage, if be higher than fiduciary level, then reduces microphone bias voltage.This step specifically comprises following several steps: step S130, if described average value signal is higher than fiduciary level, then controls, and reduces microphone bias voltage, makes the voice-grade signal with low level input microphone portion 100; Step S140 if described average value signal is lower than fiduciary level, then controls, and improves microphone bias voltage, makes the voice-grade signal with high level input microphone portion 100.
With reference to the accompanying drawings, describe the microphone input level automatic adjusting method of the portable terminal device of the present invention that as above constitutes in detail.
Described portable terminal device judges whether to have imported voice-grade signal (step S100) by microphone portion 100, if the result who judges in described step S100 has imported the voice-grade signal, then, detect the mean value (step S110) of voice-grade signal with its partes glabra 166 that inserts incoming level adjustment part 160.
Relatively and judge whether the detected voice signal average value signal of described step S110 is higher than the fiduciary level value signal (step S120) of the set level of setting.
If described step judged result is to detect the level mean value that is higher than fiduciary level, then reduce the microphone bias voltage and the output (step S130) that insert microphone portion 100, if the detected average value signal of described step is lower than the level of the set standard value signal of setting, then improves the microphone bias voltage that inserts microphone portion 100 and export (step S140).
Therefore, as above the present invention of Gou Chenging can adjust or control automatically, when the level of the voice-grade signal of the microphone portion 100 that inserts portable terminal device is low, then insert the microphone bias voltage of high level to microphone portion 100, with high sensitivity input voice-grade signal, that is, improve the sensitivity of microphone portion 100; When the level of the voice-grade signal that inserts described microphone portion 100 is high, then insert low level microphone bias voltage, with muting sensitivity input voice-grade signal to microphone portion 100.
Claims (7)
1. the microphone input level automatic regulating apparatus of a portable terminal device is characterized in that comprising following several sections:
Microphone portion, it is the analogue audio frequency level conversion of signals that inserts portable terminal device that the signal of telecommunication is imported;
Coder portion, it amplifies the signal of telecommunication that inserts from described microphone portion by the magnification ratio that is provided with, and is converted to digital electric signal and exports;
Outside enlarging section, it inserts the signal of telecommunication that described coder portion amplifies, and amplifies and inserts described coder portion again according to the magnification ratio that is provided with;
The incoming level adjustment part, it carries out smoothing processing to the signal that amplifies through described outside enlarging section and export, the output average value signal, control the bias voltage of described microphone portion, if described average value signal is higher than fiduciary level, then control to reduce the bias voltage of microphone portion,, then control to improve the bias voltage of microphone portion if described average value signal is lower than fiduciary level;
Wherein, described incoming level adjustment part comprises:
Partes glabra, the signal that its input is amplified and exported through described outside enlarging section carries out smoothing processing, the output average value signal;
Amplify bias voltage portion, it is provided with from the bias level of the signal of described partes glabra output;
Amplifier, its is according to the average value signal that inserts from described amplification bias voltage portion, adjusts the bias voltage that also output inserts described microphone portion.
2. the microphone input level automatic regulating apparatus of portable terminal device according to claim 1 is characterized in that described coder portion comprises following several sections:
The 1st enlarging section, the level of the signal of telecommunication that it inserts from described microphone portion according to the magnification ratio adjustment that is provided with outputs to described outside enlarging section with it;
The 2nd enlarging section, it is also exported according to the level of the signal of telecommunication that the magnification ratio adjustment that is provided with inserts from described outside enlarging section;
Analog to Digital Converter section, it is the electrical signal conversion that inserts from described the 2nd enlarging section digital electric signal and output.
3. the microphone input level automatic regulating apparatus of portable terminal device according to claim 1 is characterized in that:
Described partes glabra is made of resistance and the capacitor that block capacitor and being used to draws the average value signal of input signal;
Described amplification bias voltage portion connects by resistance, inserts bias voltage to the average value signal that inserts from described partes glabra.
4. the microphone input level automatic regulating apparatus of portable terminal device according to claim 1, it is characterized in that, described amplifier is according to the signal that inserts from described amplification bias voltage portion, adjustment is from the microphone bias voltage level of described coder portion output, with the form of bias voltage to the output of described microphone portion.
5. the microphone input level automatic adjusting method of a portable terminal device is characterized in that comprising:
1) input step, when having imported the voice-grade signal by microphone portion, portable terminal device carries out smoothing processing, obtains average value signal;
2) comparison step compares the average value signal obtained in the described input step and the fiduciary level of setting;
3) set-up procedure is lower than fiduciary level if described comparison step judged result is described mean value, then improves microphone bias voltage, if be higher than reference level, then reduces microphone bias voltage.
6. the microphone input level automatic adjusting method of portable terminal device according to claim 5 is characterized in that described input step comprises:
Step 1-1 judges in the microphone portion of portable terminal device whether imported the voice-grade signal;
Step 1-2 has imported the voice-grade signal if described step 1-1 judgement is thought, then carries out smoothing processing, obtains average value signal.
7. the microphone input level automatic adjusting method of portable terminal device according to claim 5 is characterized in that described set-up procedure comprises:
Step 3-1 if described average value signal is higher than fiduciary level, then controls to reduce microphone bias voltage, makes the voice-grade signal with low level input microphone portion;
Step 3-2 if described average value signal is lower than fiduciary level, then controls to improve microphone bias voltage, makes the voice-grade signal with high level input microphone portion.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020040009067A KR20050080898A (en) | 2004-02-11 | 2004-02-11 | A method and a apparatus of automatic controlling input level with microphone for mobile phone |
| KR1020040009067 | 2004-02-11 | ||
| KR10-2004-0009067 | 2004-02-11 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1655447A CN1655447A (en) | 2005-08-17 |
| CN100477510C true CN100477510C (en) | 2009-04-08 |
Family
ID=34909937
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100781981A Expired - Fee Related CN100477510C (en) | 2004-02-11 | 2004-09-17 | Apparatus and method for automatically regulating microphone input level of portable terminal |
Country Status (2)
| Country | Link |
|---|---|
| KR (1) | KR20050080898A (en) |
| CN (1) | CN100477510C (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140112483A1 (en) * | 2012-10-24 | 2014-04-24 | Alcatel-Lucent Usa Inc. | Distance-based automatic gain control and proximity-effect compensation |
| CN109618270B (en) * | 2018-12-04 | 2020-12-08 | 珠海市杰理科技股份有限公司 | Microphone input offset calibration method and microphone offset device |
-
2004
- 2004-02-11 KR KR1020040009067A patent/KR20050080898A/en not_active Application Discontinuation
- 2004-09-17 CN CNB2004100781981A patent/CN100477510C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1655447A (en) | 2005-08-17 |
| KR20050080898A (en) | 2005-08-18 |
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Granted publication date: 20090408 Termination date: 20091019 |