JPH0260102B2 - - Google Patents
Info
- Publication number
- JPH0260102B2 JPH0260102B2 JP58166956A JP16695683A JPH0260102B2 JP H0260102 B2 JPH0260102 B2 JP H0260102B2 JP 58166956 A JP58166956 A JP 58166956A JP 16695683 A JP16695683 A JP 16695683A JP H0260102 B2 JPH0260102 B2 JP H0260102B2
- Authority
- JP
- Japan
- Prior art keywords
- pass filter
- voltage
- frequency
- vehicle
- vehicle speed
- 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.)
- Expired - Lifetime
Links
- 230000008054 signal transmission Effects 0.000 claims description 3
- 230000005236 sound signal Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 239000003990 capacitor Substances 0.000 description 3
- 210000005069 ears Anatomy 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
- G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/10—Applications
- G10K2210/117—Nonlinear
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/10—Applications
- G10K2210/128—Vehicles
- G10K2210/1282—Automobiles
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/10—Applications
- G10K2210/128—Vehicles
- G10K2210/1282—Automobiles
- G10K2210/12821—Rolling noise; Wind and body noise
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/30—Means
- G10K2210/301—Computational
- G10K2210/3011—Single acoustic input
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/30—Means
- G10K2210/301—Computational
- G10K2210/3028—Filtering, e.g. Kalman filters or special analogue or digital filters
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/30—Means
- G10K2210/301—Computational
- G10K2210/3046—Multiple acoustic inputs, multiple acoustic outputs
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Noise Elimination (AREA)
- Circuits Of Receivers In General (AREA)
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、走行中に発生する風切り音を抑圧
し、快的な通話を楽しむことができるように構成
した車載用通話装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an in-vehicle telephone communication device configured to suppress wind noise generated while the vehicle is running so that the user can enjoy pleasant telephone conversations.
従来例の構成とその問題点
近年、自動二輪車へ乗る人の数は著しく増加
し、それに伴つて自動二輪車でも音楽とか通話を
楽しもうとする気運が高まつており、既にそのよ
うな目的を満たす製品も発表されている。Configuration of conventional examples and their problems In recent years, the number of people riding motorcycles has increased significantly, and with this, there has been a growing trend to enjoy music and talking on motorcycles. Products have also been announced.
以下に従来の自動二輪車に用いられる車載用通
話装置について説明する。 A conventional vehicle-mounted communication device used in a motorcycle will be described below.
第１図は従来の自動二輪車に用いられる車載用
通話装置の構成を示すものであり、図中、１，２
は第１及び第２のマイクロホン、３，４は第１及
び第２の前置増幅器、５は加算器、６は低周波増
幅器、７，８は第１及び第２の小型スピーカであ
る。第１のマイクロホン１と第１の小型スピーカ
７は運転者のヘルメツト内に設置され、第２のマ
イクロホン２と第２の小型スピーカ８は後部座席
乗者のヘルメツト内に設置される。 Figure 1 shows the configuration of a conventional in-vehicle communication device used in motorcycles.
are first and second microphones, 3 and 4 are first and second preamplifiers, 5 is an adder, 6 is a low frequency amplifier, and 7 and 8 are first and second small speakers. The first microphone 1 and the first small speaker 7 are installed in the helmet of the driver, and the second microphone 2 and the second small speaker 8 are installed in the helmet of the rear seat passenger.
以上のように構成された従来の自動二輪車に用
いられる通話装置について、以下その動作につい
て説明する。運転者と後部座席乗車者の発生した
音声は、それぞれ前記第１及び第２のマイクロホ
ン１，２によつて電気信号に変換され、前記第１
及び第２の前置増幅器３，４によつて増幅された
後、前記加算器５の二つの被加算信号として入力
される。従つて前記加算器５の出力は前記二信号
の重畳されたものとなる。 The operation of the conventional communication device used in a motorcycle configured as described above will be described below. The voices generated by the driver and the rear seat passengers are converted into electrical signals by the first and second microphones 1 and 2, respectively, and
After being amplified by the second preamplifiers 3 and 4, the signals are input to the adder 5 as two signals to be added. Therefore, the output of the adder 5 is a superposition of the two signals.
以上のようにして得られた信号は、前記低周波
増幅器６で増幅され、前記第１及び第２の小型ス
ピーカ７，８を並列に駆動し、音声信号に変換し
て前記運転者と、前記後部座席乗車者に伝える。
このようにして前後二人の乗車者は、通話を楽し
むことができるのである。 The signal obtained as described above is amplified by the low frequency amplifier 6, drives the first and second small speakers 7 and 8 in parallel, and is converted into an audio signal to be transmitted to the driver and the driver. Inform the rear seat passengers.
In this way, the two passengers in front and behind can enjoy talking on the phone.
しかしながら、上記のような構成では、走行時
の風切り音が音声信号と重畳されてマイクロホン
１，２に入力されるため、自動二輪車にて高速走
行を行つた場合に乗車者の近傍で発生する風切り
音が耳につき、快適な通話を楽しむことができな
いという欠点を有するとともに、安全上の問題と
もなつていた。 However, with the above configuration, the wind noise generated when the motorcycle is traveling is superimposed with the audio signal and input to the microphones 1 and 2, so the wind noise generated near the rider when the motorcycle is traveling at high speed is This has the disadvantage that the sound hits the ears and makes it impossible to enjoy comfortable calls, and it also poses a safety problem.
発明の目的
本発明は、上記従来の問題点を解決するもの
で、簡素な構成により走行中の風切り音を抑圧す
ることのできる車載用通話装置を提供することを
目的とする。OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide an in-vehicle communication device that can suppress wind noise during driving with a simple configuration.
発明の構成
上記の目的を達成するため、本発明は、車速に
応じた周期のパルスを発生するパルス発生器から
のパルス周期に比例した直流電圧を制御入力とし
て遮断周波数を可変する高域通過フイルタを信号
伝送路間に挿入したことを特長とするものであ
り、マイクロホンに入力される走行時の風切り音
を車速に応じて自動的に抑圧することのできる利
点を有するものである。Structure of the Invention In order to achieve the above object, the present invention provides a high-pass filter whose cut-off frequency is varied by using as a control input a DC voltage proportional to the pulse period from a pulse generator that generates pulses whose period corresponds to the vehicle speed. is inserted between the signal transmission paths, and has the advantage of being able to automatically suppress wind noise during driving that is input to the microphone according to the vehicle speed.
実施例の説明
第２図は本発明の一実施例における自動二輪車
に好適な車載用通話装置の構成図を示すものであ
り、第１図と同一符号は同一のものを示す。第２
図において９は直流制御電圧の値によつて遮断周
波数を可変できる高域通過フイルタ、１０は車速
に応じた周期のパルスを発生するパルス発生器、
１１は単安定マルチバイブレータと積分器等から
構成され、入力されたパルスの周期に応じて直流
電圧を出力する周波数電圧変換器である。DESCRIPTION OF THE EMBODIMENTS FIG. 2 shows a configuration diagram of an in-vehicle communication device suitable for a motorcycle according to an embodiment of the present invention, and the same reference numerals as in FIG. 1 indicate the same parts. Second
In the figure, 9 is a high-pass filter whose cutoff frequency can be varied depending on the value of the DC control voltage, 10 is a pulse generator that generates pulses with a period corresponding to the vehicle speed,
Reference numeral 11 denotes a frequency-voltage converter, which is composed of a monostable multivibrator, an integrator, etc., and outputs a DC voltage according to the period of the input pulse.
第１のマイクロホン１と第１の前置増幅器３を
縦列に接続したものと、第２のマイクロホン２と
第２の前置増幅器４を縦列接続したものとを加算
器５の二つの入力として二系統の信号を重畳し、
前記加算器５の出力に高域通過フイルタ９を接続
し、前記高域通過フイルタ９の出力に低周波増幅
器６を接続し、さらに前記低周波増幅器６の出力
に第１及び第２の小型スピーカ７，８を並列に接
続する構成をとる。ここで、前記高域通過フイル
タ９はパルス発生装置１０と周波数電圧変換器１
１を縦列に接続することによつて得られる、車速
に比例した直流電圧によつて、その遮断周波数を
制御することができる。 The two inputs of the adder 5 are the first microphone 1 and the first preamplifier 3 connected in cascade, and the second microphone 2 and the second preamplifier 4 connected in cascade. Superimpose the system signal,
A high-pass filter 9 is connected to the output of the adder 5, a low-frequency amplifier 6 is connected to the output of the high-pass filter 9, and first and second small speakers are connected to the output of the low-frequency amplifier 6. 7 and 8 are connected in parallel. Here, the high-pass filter 9 includes a pulse generator 10 and a frequency-voltage converter 1.
The cutoff frequency can be controlled by the direct current voltage proportional to the vehicle speed obtained by connecting the motors 1 in series.
以上のように構成された本実施例の自動二輪車
に好適な車載用通話装置について以下その動作を
説明する。まず運転者の発する音声は、第１のマ
イクロホン１にて電気信号に変換され、第１の前
置増幅器３で増幅された後、加算器５の一方の入
力に供給される。また後部座席乗車者が発する音
声は第２のマイクロホン２にて電気信号に変換さ
れ、第２の前置増幅器４で増幅された後、前記加
算器５の他方の入力に供給される。従つて前記加
算器５の出力には二人の音声の重畳された信号が
得られる。前記加算器５の出力は、高域通過フイ
ルタ９を通過した後、低周波増幅器６にて電力増
幅され、第１、第２の小型スピーカ７，８により
出力される。 The operation of the in-vehicle communication device suitable for a motorcycle according to the present embodiment configured as described above will be described below. First, the voice emitted by the driver is converted into an electrical signal by the first microphone 1, amplified by the first preamplifier 3, and then supplied to one input of the adder 5. Furthermore, the sound emitted by the passenger in the rear seat is converted into an electrical signal by the second microphone 2, amplified by the second preamplifier 4, and then supplied to the other input of the adder 5. Therefore, the output of the adder 5 is a signal in which the voices of the two people are superimposed. The output of the adder 5 passes through a high-pass filter 9, is power-amplified by a low-frequency amplifier 6, and is outputted by first and second small speakers 7 and 8.
ところで車載用通話装置においては、前に説明
したように走行中に発生する風切り音が問題とな
る。この風切り音は、音声信号に重畳されること
により音声信号の質を劣下せしめることになる
が、低速走行中には低い周波数成分に分布し、車
速が増すにつれ姿第に高域に移つてゆくことが知
られており、信号伝送間に車速に応じて遮断周波
数の可変できる前記高域通過フイルタ９を挿入す
ることにより、前記の不要な風切り音を効果的に
抑圧することができる。 By the way, as explained above, wind noise generated while the vehicle is running poses a problem in the vehicle-mounted communication device. This wind noise degrades the quality of the audio signal by being superimposed on it, but it is distributed in low frequency components when driving at low speeds, and gradually shifts to higher frequencies as the vehicle speed increases. By inserting the above-mentioned high-pass filter 9 whose cut-off frequency can be varied according to the vehicle speed during signal transmission, it is possible to effectively suppress the above-mentioned unnecessary wind noise.
すなわち、前記高域通過フイルタ９の入出力特
性は第３図に示すように、車速が零に等しい時は
図中実線で示す特性をもち、このとき音声信号は
抑圧されることなく前記高域通過フイルタ９を通
過する。車速が増加するにつれ前記高域通過フイ
ルタ９の遮断周波数の値は大きくなり、第３図で
点線で示す特性を持つ。この時の遮断同波数の大
きさを音声信号をそこなわない範囲で風切り音を
最大に抑圧する大きさに設定することによつて風
切り音の少い快適な通話を実現するのである。 That is, as shown in FIG. 3, the input/output characteristics of the high-pass filter 9 have the characteristics shown by the solid line in the figure when the vehicle speed is equal to zero, and at this time, the audio signal is not suppressed and passes through the high-pass filter 9. It passes through the pass filter 9. As the vehicle speed increases, the value of the cutoff frequency of the high-pass filter 9 increases, and the characteristic is shown by the dotted line in FIG. 3. By setting the magnitude of the cut-off frequency at this time to a magnitude that suppresses wind noise to the maximum without damaging the audio signal, a comfortable conversation with little wind noise is realized.
ここで車速に応じて前記高域通過フイルタ９の
遮断周波数を可変する回路を実例を用いて以下に
記す。尚、高域通過フイルタ９へ制御用の直流電
圧を供給する回路は、既に車載用の自動音量調節
器等に用いられている周知の回路である。前記高
域通過フイルタ９は例えば第４図に示す回路にて
容易に実現できる。第４図において、１２はコン
デンサ、１３，１５は抵抗、１４はトランジスタ
である。この回路において、信号は端子１６より
入力され、端子１８より出力される。また第２図
中の周波数電圧変換器１４より出力される制御用
の直流電圧はトランジスタ１４のベース端子１７
より加えられる。 Here, a circuit for varying the cutoff frequency of the high-pass filter 9 according to the vehicle speed will be described below using an example. Note that the circuit that supplies the control DC voltage to the high-pass filter 9 is a well-known circuit that has already been used in automotive automatic volume controllers and the like. The high-pass filter 9 can be easily realized by the circuit shown in FIG. 4, for example. In FIG. 4, 12 is a capacitor, 13 and 15 are resistors, and 14 is a transistor. In this circuit, a signal is input from a terminal 16 and output from a terminal 18. Further, the control DC voltage output from the frequency-voltage converter 14 in FIG.
More added.
いまコンデンサ１２の値をＣ、抵抗１３の値を
R1、抵抗１５の値をR2、またトランジスタ１４
のエミツタコレクタ間の等価抵抗値をｒとおく
と、この高域通過フイルタ９の遮断周波数cは
c＝１／2πCRT
ただしRT＝（R1＋ｒ）R2／（R1＋ｒ）＋R2
で与えられる。ここで、前記等価抵抗ｒの値はト
ランジスタ１４のベース端子１７に加えられる直
流電圧の値に応じて変化するので、上式において
ｒの値を変化することにより、前記遮断周波数c
の値を制御することができるのである。 Now, the value of capacitor 12 is C, and the value of resistor 13 is
R 1 , the value of the resistor 15 is R 2 , and the value of the transistor 14 is
Letting r be the equivalent resistance value between the emitter and collector of It is given by 2 . Here, since the value of the equivalent resistance r changes depending on the value of the DC voltage applied to the base terminal 17 of the transistor 14, by changing the value of r in the above equation, the cutoff frequency c
The value of can be controlled.
尚、上記の説明は自動二輪車に用いられる車載
用通話装置について説明したが、自動二輪車以外
の自動車に搭載する通話装置にも適用可能である
ことは言うまでもない。 It should be noted that although the above description has been made regarding an in-vehicle communication device used in a motorcycle, it goes without saying that the present invention is also applicable to a communication device installed in a vehicle other than a motorcycle.
発明の効果
本発明は車速に応じた周期のパルスを発生する
パルス発生器と、前記パルス周期に応じた直流電
圧を発生する周波数電圧変換器と、前記直流電圧
を制御入力として遮断周波数を可変する高域通過
フイルタとを設けたので、マイクロホンに入力さ
れる走行時の風切り音を車速に応じて自動的に抑
圧することができ、快適な通話を楽しむことがで
き、また、安全運転のためにも優れた車載用通話
装置を実現できるものである。Effects of the Invention The present invention includes a pulse generator that generates pulses with a period that corresponds to the vehicle speed, a frequency-voltage converter that generates a DC voltage that corresponds to the pulse period, and a variable cutoff frequency that uses the DC voltage as a control input. A high-pass filter is installed to automatically suppress the wind noise that is input into the microphone while driving according to the vehicle speed, allowing you to enjoy comfortable calls and also for safe driving. It is also possible to realize an excellent in-vehicle communication device.
第１図は従来の自動二輪車に用いられる車載用
通話装置のブロツク図、第２図は本発明の一実施
例における自動二輪車に好適な車載用通話装置の
ブロツク図、第３図は第２図の高域通過フイルタ
の周波数特性が制御電圧によつて変化することを
示す特性図、第４図は第２図の高域通過フイルタ
の一実施例を示す回路図である。
１，２……マイクロホン、３，４……前置増幅
器、５……加算器、６……低周波増幅器、７，８
……小型スピーカ、９……高域通過フイルタ、１
０……パルス発生器、１１……周波数電圧変換
器、１２……コンデンサ、１３，１５……抵抗、
１４……トランジスタ。
FIG. 1 is a block diagram of a conventional in-vehicle communication device used in a motorcycle, FIG. 2 is a block diagram of an in-vehicle communication device suitable for a motorcycle according to an embodiment of the present invention, and FIG. FIG. 4 is a circuit diagram showing an embodiment of the high-pass filter of FIG. 2. FIG. 1, 2...Microphone, 3, 4...Preamplifier, 5...Adder, 6...Low frequency amplifier, 7,8
...Small speaker, 9 ...High pass filter, 1
0... Pulse generator, 11... Frequency voltage converter, 12... Capacitor, 13, 15... Resistor,
14...Transistor.
Claims (1)
発生器と、前記パルス周期に応じた直流電圧を発
生する周波数電圧変換器と、前記直流電圧を制御
入力として遮断周波数を可変する高域通過フイル
タを備え、前記高域通過フイルタを信号伝送路間
に挿入することにより、マイクロホンに入力され
る走行時の風切り音を車速に応じて自動的に抑圧
するように構成したことを特徴とする車載用通話
装置。1. A pulse generator that generates a pulse with a period corresponding to the vehicle speed, a frequency-voltage converter that generates a DC voltage according to the pulse period, and a high-pass filter that uses the DC voltage as a control input to vary the cutoff frequency. An in-vehicle phone call, characterized in that the high-pass filter is inserted between the signal transmission paths to automatically suppress wind noise input to the microphone during driving according to the vehicle speed. Device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58166956A JPS6058733A (en) | 1983-09-09 | 1983-09-09 | In-vehicle communication device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58166956A JPS6058733A (en) | 1983-09-09 | 1983-09-09 | In-vehicle communication device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6058733A JPS6058733A (en) | 1985-04-04 |
| JPH0260102B2 true JPH0260102B2 (en) | 1990-12-14 |
Family
ID=15840733
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58166956A Granted JPS6058733A (en) | 1983-09-09 | 1983-09-09 | In-vehicle communication device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6058733A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4754486A (en) * | 1987-04-13 | 1988-06-28 | John J. Lazzeroni | Motorcycle stereo audio system with VOX intercom |
| US5243659A (en) * | 1992-02-19 | 1993-09-07 | John J. Lazzeroni | Motorcycle stereo audio system with vox intercom |
| US6295364B1 (en) * | 1998-03-30 | 2001-09-25 | Digisonix, Llc | Simplified communication system |
| US9871605B2 (en) | 2016-05-06 | 2018-01-16 | Science Applications International Corporation | Self-contained tactical audio distribution device |
-
1983
- 1983-09-09 JP JP58166956A patent/JPS6058733A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6058733A (en) | 1985-04-04 |
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