JPH03159400A - Ultradirectional loudspeaker system - Google Patents
Ultradirectional loudspeaker systemInfo
- Publication number
- JPH03159400A JPH03159400A JP1298457A JP29845789A JPH03159400A JP H03159400 A JPH03159400 A JP H03159400A JP 1298457 A JP1298457 A JP 1298457A JP 29845789 A JP29845789 A JP 29845789A JP H03159400 A JPH03159400 A JP H03159400A
- Authority
- JP
- Japan
- Prior art keywords
- sound
- ultradirectional
- ultrasonic
- speaker
- loudspeaker
- 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.)
- Granted
Links
- 230000005236 sound signal Effects 0.000 description 11
- 238000010586 diagram Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 241000201776 Steno Species 0.000 description 3
- 238000002604 ultrasonography Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2217/00—Details of magnetostrictive, piezoelectric, or electrostrictive transducers covered by H04R15/00 or H04R17/00 but not provided for in any of their subgroups
- H04R2217/03—Parametric transducers where sound is generated or captured by the acoustic demodulation of amplitude modulated ultrasonic waves
Landscapes
- Circuit For Audible Band Transducer (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は展示場や娯楽施設等の放送設備に適用される超
指向性スピーカーに関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a superdirectional speaker applied to broadcasting equipment in exhibition halls, entertainment facilities, and the like.
パラメトリック・スピーカーについては，特開昭６０−
１６７５９７号等で超音波を低減するための機構が提案
されているが，パラメトリンクスビーカーから音声とと
もに発せられる超音波を利用して物体あるいは人間から
の超音波の反射波を利用するような技術は提案されてい
ない。従来のパラメトリンクスピーカーの構成を第７図
に示すと，音源３０の音はアンプ３１で増幅され，超指
向性スピーカー３２で３４として発音される。視聴者１
９からの反射波３３は何んら処理されないままである。Regarding parametric speakers, please refer to Japanese Patent Application Laid-Open No. 60-
A mechanism for reducing ultrasonic waves has been proposed in No. 167597, etc., but there is no technology that utilizes the reflected waves of ultrasonic waves from objects or people by using the ultrasonic waves emitted along with sound from a parametric beaker. Not proposed. When the configuration of a conventional parametric link speaker is shown in FIG. 7, the sound from a sound source 30 is amplified by an amplifier 31, and is output as 34 by a superdirectional speaker 32. Viewer 1
The reflected wave 33 from 9 remains unprocessed.
パラメトリックスビーカーでは前述のように可聴周波数
と共に発生し，無くすことのできない超音波を利用した
技術はない。視聴者等が超指向性スピーカーの前方の可
聴域に存在するか否かを，超音波の視聴者等からの反射
波を検知することにより識別し，視聴者の有無に応じて
超指向性スピーカーの作用（例えば，音源の切換えや動
作）を変化させることができれば，視聴者にとって聞き
やすい音量でスピーカーからの音声を聴取することがで
きたり，又は視聴者が存在する時のみ必要な情報を流す
，等の切換えが可能となるが，このような技術の開発が
今までに望まれていた。本発明はこのような課題を解決
するためになされたものである。As mentioned above, there is no technology for parametric beakers that uses ultrasonic waves that are generated along with audio frequencies and cannot be eliminated. It is possible to identify whether a viewer, etc. is present in the audible range in front of the super-directional speaker by detecting the ultrasonic wave reflected from the viewer, etc. If it is possible to change the effect of the speaker (for example, switching or operating the sound source), it is possible to listen to the sound from the speaker at a volume that is easy for the viewer to hear, or to transmit necessary information only when the viewer is present. , etc., and the development of such technology has been desired for some time. The present invention has been made to solve these problems.
本発明はこのような課題を解決するために，超指向性ス
ピーカーの発音体の設置された面の周囲に超音波受波器
Ｃセンサー）を配置し．超指向性スピーカーから発せら
れた超音波を含む音声のうち，前方の視聴者等の物体か
ら反射される超音波の信号を受信し，受信信号の処理や
超指向性スピーカーの構成品の音源を制御する制御装置
を設けて超指向性スピーカーに機能を付加したものであ
る。In order to solve this problem, the present invention arranges an ultrasonic receiver (C sensor) around the surface where the sounding body of the superdirectional speaker is installed. Among the sounds containing ultrasonic waves emitted from the super-directional speaker, the ultrasonic signal reflected from objects such as the viewer in front is received, and the received signal is processed and the sound source of the components of the super-directional speaker is detected. This is a super-directional speaker with added functionality by providing a control device.
即ち，本発明は，パラメトリック・アレイを使った超指
向性スピーカーと音源からの入力信号を振幅変調や増幅
して出力信号を出力するための回路から構成される超指
向性スピーカーシステムにふ・いて，超指向性スピーカ
ーから音声と一緒に発信される超音波が超指向性スピー
カー前方の視聴者等から反射する超音波を受信する受信
装置と，受信した超音波の信号を処理することにより音
源の切換えを制御する装置とを具備してなることを特徴
とする超指向性スピーカーシステムを提供するものであ
る。That is, the present invention is based on a super-directional speaker system consisting of a super-directional speaker using a parametric array and a circuit for amplitude modulating and amplifying an input signal from a sound source and outputting an output signal. , a receiving device that receives the ultrasonic waves emitted along with the sound from the super-directional speaker and reflected from the audience in front of the super-directional speaker, and a receiver that processes the received ultrasonic signal to identify the sound source. The present invention provides a superdirectional speaker system characterized by comprising a device for controlling switching.
超指向性スピーカーから発せられる音声には可聴域の音
波（〜約２ ０ Ｋ［｛ｚ ）以外に超音波（約４ ０
ＫＨｚ ）領域の音波が含まれ，超音波領域の周波数
域での音圧レペルは可聴域に比べて同等のレベルを有す
るととが知られている。超指向性スピーカーから発する
音声はこの超音波を必然的に含むので音声が発せられて
いる間はこの超音波を利用することが可能である。In addition to sound waves in the audible range (about 20K [{z]), the sound emitted from superdirectional speakers includes ultrasonic waves (about 40K [{z]).
It is known that the sound pressure level in the ultrasonic frequency range is equivalent to that in the audible range. Since the sound emitted from the superdirectional speaker necessarily includes this ultrasonic wave, it is possible to utilize this ultrasonic wave while the sound is being emitted.
本発明ではこの超音波が超指向性スピーカー前面に視聴
者が存在する場合に反射してスピーカー前面の超音波受
話器で受信され，ある一定のレベルの信号を検知し，視
聴者がスピーカーの前にいると判断して音源を切換え適
切な情報を流すようにすることができる。In the present invention, when there is a viewer in front of the superdirectional speaker, this ultrasonic wave is reflected and received by the ultrasonic receiver in front of the speaker, and a signal of a certain level is detected, and the viewer is in front of the speaker. It is possible to switch the sound source and broadcast appropriate information when it is determined that there is a problem.
第１図は本発明の実施例で超指向性スピーカーシステム
の正面図，第２図はその■−■断面図である。両図にお
いて，超指向性スピーカー１は発音体２の集合により構
成され，支持金具３と支持台４により支持されている。FIG. 1 is a front view of a super-directional speaker system according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line 1--2. In both figures, a superdirectional speaker 1 is constituted by a set of sounding bodies 2, and is supported by a support fitting 3 and a support base 4.
支持金具３は超指向性スピーカーＩの周囲に装備され，
超音波受波器５が適当数（第１図の実施例では４個）取
付けられている。発音体２は超指向性スピーカーｌの制
御基盤６に取付けられており，音声信号接続コネクタ７
を介して音声信号線８から伝達される音声信号を再生し
発音する。発音体２から発せられる超指向性（強指向性
）の音声信号には人間の可聴域音以外の超音波域（例え
ば４ ０ ｝Ｇ｛ｚ ）の音が含まれており，超指向性
スピーカー１の前面方向に可聴音と同時に発信されてい
る。この発信された超音波の反射波の一部を超音波受波
器５が受信し，受信信号線９を介して超音波信号処理器
１０（第３図に図示）へ伝達する。The support fitting 3 is installed around the super-directional speaker I,
A suitable number of ultrasonic receivers 5 (four in the embodiment shown in FIG. 1) are installed. The sounding body 2 is attached to the control board 6 of the superdirectional speaker l, and is connected to the audio signal connection connector 7.
The audio signal transmitted from the audio signal line 8 via the audio signal line 8 is reproduced and generated. The superdirectional (strongly directional) audio signal emitted from the sounding body 2 includes sounds in the ultrasonic range (for example, 4 0 } G{z) other than the human audible range, and the superdirectional speaker An audible sound is simultaneously transmitted in the direction of the front of the camera. A part of the reflected wave of the transmitted ultrasound is received by the ultrasound receiver 5 and transmitted to the ultrasound signal processor 10 (shown in FIG. 3) via the reception signal line 9.
超音波信号処理器１０では受信した信号レベルの変換処
理をして，制御器１１へ受信超音波信号を送信する。第
３図は，本実施例の構成を示すブロック図で，超指向性
スピーカー１を駆動するために必要な機器構成である。The ultrasonic signal processor 10 converts the received signal level and transmits the received ultrasonic signal to the controller 11. FIG. 3 is a block diagram showing the configuration of this embodiment, which is the equipment configuration required to drive the superdirectional speaker 1.
カセノトテープ等を使用した音源（Ａ）１２と音源（Ｂ
） １ ３から発せられる音声信号はマイクロコンピュ
ータを利用した制御器１１による切換信号１７により入
力信号切換器１４０作用でいずれか一つの音源の音声信
号が信号変調回路１５で変調されパワーアンブ１６にて
増幅され，音声信号線８を介して超指向性スピーカー１
から発音される。Sound source (A) 12 and sound source (B) using casenote tape etc.
) The audio signal emitted from one of the sound sources is modulated by the signal modulation circuit 15 by the action of the input signal switch 140 in response to the switching signal 17 from the controller 11 using a microcomputer, and then the audio signal from one of the sound sources is modulated by the signal modulation circuit 15 and then sent to the power amplifier 16. The signal is amplified and sent to the superdirectional speaker 1 via the audio signal line 8.
pronounced from
第４図で，超指向性スピーカー１から発せられる超音波
１８を含む音声信号は発音体２の作用により発音体２の
前面方向に強指向性を持ち発信される。超指向性スピー
カー１の前面に夜聴者１９が存在した場合は，超音波１
８を含む音声信号のうちの視聴者１９で反射される反射
波２０はそのうちの超音波の分たけが超音波受波器５に
て受信され，制御部２３にて処理される。な釦，２１は
超指向性スピーカーのアンプ部であり，２２は音源部で
ある。In FIG. 4, an audio signal including an ultrasonic wave 18 emitted from a superdirectional speaker 1 is transmitted with strong directivity in the front direction of the sounding body 2 due to the action of the sounding body 2. If a night listener 19 is present in front of the superdirectional speaker 1, the ultrasonic wave 1
Of the reflected waves 20 reflected by the viewer 19 out of the audio signals including 8, only the ultrasonic waves are received by the ultrasonic receiver 5 and processed by the controller 23. 21 is the amplifier section of the super-directional speaker, and 22 is the sound source section.
第５図は超音波受話器５で受信して制御器１１へ送られ
る信号の波形図で，超音波信号処理器１０で処理され，
制御器１ｌへ送られる反射波２０の受信信号を縦軸に受
信信号レベル，横軸に時間を取って表わした図である。FIG. 5 is a waveform diagram of a signal received by the ultrasonic receiver 5 and sent to the controller 11, processed by the ultrasonic signal processor 10,
It is a diagram in which the received signal of the reflected wave 20 sent to the controller 1l is expressed with the received signal level on the vertical axis and the time on the horizontal axis.
視聴者１９が超指向性スピーカーｌの前面前方に存在し
ないときの期間（ＴＡ）と存在する期間（ＴＢ）では受
信信号レベルは後者の場合が大きい。受信信号レベルの
しきい値（Ｐｍ）は視聴者１９からの反射波２０がある
かないかの判定に使用する任意の値の受信信号レベルで
ある。Between the period when the viewer 19 is not present in front of the superdirectional speaker l (TA) and the period when the viewer 19 is present (TB), the received signal level is higher in the latter case. The received signal level threshold (Pm) is an arbitrary value of the received signal level used to determine whether there is a reflected wave 20 from the viewer 19.
第６図は．制御器１ｌで実行されるマイクロコンピュー
タ用の処理流れ図である。ステソプ■では，音源（〜１
２を入力信号切換器１４で切換えて信号変調回路１５の
入力音源とし超指向性スピーカー１で発音され，ステッ
プ■では，任意の時間間隔（△ｔ）で検知するしきい値
（ｐ ｍ ）以上の受信信号レベルの発生回数（ｎ）を
初期化する。ステノブ■では，超音波受信信号（ｐ）す
なわち超音波信号処理器１０より送られる反射波２０の
受信信号レベルを入力し，ステップ＠では，しきい値（
Ｐ―）と比較し，比較結果が真であればステップ■で受
信信号レベルの発生回数（ｎ）をカウントアップし，比
較結果が偽であればステップ■へ戻る。次にステップの
では，受信信号レベルの発生最小回数（ｎ．．）を任意
の値に設定してふ・き，（ｎ）と比較する。判定結果が
偽ならば，ステップ＠で任意の時間間隔（Δｔ）を待っ
た後にステップ＠へ戻る。判定結果が真ならば，ステノ
プ■で音源（Ａ）１２から音源（Ｂ） １ ３に入力信
号切換器１４を動作させて切換え，音源（Ｂ） １ ３
を超指向性スピーカー１から発音させる。Figure 6 is. It is a process flowchart for the microcomputer executed by the controller 1l. In Stesop■, the sound source (~1
2 is switched by the input signal switch 14 and used as the input sound source of the signal modulation circuit 15, and the sound is produced by the superdirectional speaker 1. In step 2, the sound is generated at an arbitrary time interval (△t) above the threshold value (p m ) for detection. The number of occurrences (n) of the received signal level is initialized. In Steno knob ■, input the ultrasonic received signal (p), that is, the received signal level of the reflected wave 20 sent from the ultrasonic signal processor 10, and in step @, enter the threshold value (
P-), and if the comparison result is true, the number of occurrences (n) of the received signal level is counted up in step (2), and if the comparison result is false, the process returns to step (2). In the next step, the minimum number of times the received signal level occurs (n..) is set to an arbitrary value and compared with (n). If the determination result is false, the process returns to step @ after waiting for an arbitrary time interval (Δt) at step @. If the judgment result is true, operate the input signal switch 14 to switch from the sound source (A) 12 to the sound source (B) 1 3 using the steno panel ■, and switch the sound source (B) 1 3.
is sounded from the super directional speaker 1.
ステノブ■は■と同様に再び超音波受信信号（Ｐ）を入
力し，ステップ■でしきい値（Ｐａｌｍ）と比較し．比
較結果が真ならば■へ戻り，比較結果が偽ならば■へ戻
る。ステソプ■で△ｔ時間待ち，■へ戻すのは，視聴者
１９が超指向性スピーカー１の前面前方を横切る等の短
時間しか存在しない場合に，ステップ■で音源（８）１
２から音源（Ｂ） １ ３へ切換えることを防止するた
めで連続して（Δｔ Ｘ ｎ ｍ ）時間以上，視聴者
１９が超指向性スピーカー１前面前方にいる間のみ，ス
テップ■で音源（Ａ）１２の例えばバックグランドミュ
ージック（ＢＧＭ）の入力を音源（Ｂ） １ ３の例え
ば特定の案内放送の入力に切換えて視聴者ｌ９の必要な
情報を超指向性スピーカー１より発音できるようにする
。Steno knob ■ inputs the ultrasonic reception signal (P) again in the same way as ■, and compares it with the threshold value (Palm) in step ■. If the comparison result is true, return to ■; if the comparison result is false, return to ■. The reason for waiting △t time in step ■ and returning to ■ is when the viewer 19 is present for only a short time, such as when the viewer 19 crosses the front of the super-directional speaker 1, and the sound source (8) 1 is
In order to prevent the switching from sound source (B) 1 to sound source (B) 1 to 3, only while the viewer 19 is in front of the superdirectional speaker 1 for more than (Δt ) 12, for example, background music (BGM), is switched to the input of, for example, a specific guidance broadcast from the sound source (B) 13, so that information necessary for the viewer 19 can be output from the super-directional speaker 1.
以上のように，視聴者１９の存在するか否かを検知して
超指向性スピーカー１から発する音声を自動的に切換え
て放送する。As described above, the presence or absence of the viewer 19 is detected and the sound emitted from the super-directional speaker 1 is automatically switched and broadcast.
本発明の超指向性スピーカーシステムの使われ方の例と
しては，（ｌ）デパート，駅あるいは博覧会会場等での
催し案内放送に訃いて，通常はＢＧＭあるいは．超音波
（約４ ０ ｝Ｇ｛ｚ ）のみの信号を流してふ・き，
視聴者をとらえる事により催し案内に切換えるよう々シ
ステムに活用できるし，又｛２｝盲人案内での盲人の存
在をとらえて前記の（１）と同様に行先案内の放送に切
換えるようなシステム，等がある。Examples of how the super-directional speaker system of the present invention is used include (l) broadcasting information on events at department stores, stations, exhibition halls, etc., usually as BGM or . A signal of only ultrasonic waves (approximately 40 GHz) is transmitted,
By capturing the audience, it can be used in a system that switches to broadcasting event information, and {2} A system that detects the presence of a blind person in a blind person guide and switches to broadcasting destination information in the same way as in (1) above. etc.
以上説明の本発明の超指向性スピーカーシステムによれ
ば，超指向性スピーカーで可聴域の音声と同時に発生す
る超音波を信号発生源とし，これを利用するため，超音
波発生回路なしで装置が構成できると共に超指向性スピ
ーカーの強指向性の特性を利用し，超音波による超指向
性スピーカー前面で前方の視聴者の有無を判定すること
により，視聴者の有無に応じて超指向性スピーカーの音
声を自動的に切換えて状況に応じた放送が選択できるも
のである。According to the super directional speaker system of the present invention as described above, the ultrasonic waves generated simultaneously with audio in the audible range by the super directional speakers are used as a signal generation source, so that the device can be operated without an ultrasonic generation circuit. By using the strong directional characteristics of super-directional speakers and determining the presence or absence of a viewer in front of the super-directional speaker using ultrasonic waves, the super-directional speaker can be It is possible to automatically switch the audio and select the broadcast according to the situation.
第１図は本発明の実施例で超指向性スピーカーシステム
の正面図．第２図は第１図における■−■断面図，第３
図は本発明の実施例の装置構成を示すブロノク図，第４
図は本発明の実施例の作用を示す説明図，第５図は本実
施例での超音波受波器の受信信号の一例を示す信号波形
図，第６図は本実施例の制御装置のフローチャート，第
７図は従来の超指向性スピーカーシステムの作用を示す
説明図である。
１・・・超指向性スピーカー，２・・・発音体，５超音
波受波器．１０・・・超音波信号処理器．１１・・・制
御器，１２・・・音源（Ａ），１３・・・音源（Ｂ），
１４・・・入力信号切換器，１５・・・信号変調回路，
１６・・・パワーアンプ，１７・・・切換信号，１８・
・・超音波を含む音声信号．１９・・・視聴者，２０・
・・反射波．２１・・・アンプ部，２２・・・音源部，
２３・・・制御部。
イ（理大 石
川苛
第２図
第１図
第″７図Figure 1 is a front view of a superdirectional speaker system according to an embodiment of the present invention. Figure 2 is a sectional view taken along ■-■ in Figure 1.
The figure is a Bronnock diagram showing the device configuration of an embodiment of the present invention.
The figure is an explanatory diagram showing the operation of the embodiment of the present invention, Fig. 5 is a signal waveform diagram showing an example of a received signal of the ultrasonic receiver in this embodiment, and Fig. 6 is a diagram of the control device of this embodiment. The flowchart in FIG. 7 is an explanatory diagram showing the operation of a conventional superdirectional speaker system. 1...Super directional speaker, 2...Sounding body, 5 Ultrasonic wave receiver. 10... Ultrasonic signal processor. 11...Controller, 12...Sound source (A), 13...Sound source (B),
14... Input signal switcher, 15... Signal modulation circuit,
16...Power amplifier, 17...Switching signal, 18.
...Audio signal containing ultrasonic waves. 19...viewer, 20.
...Reflected wave. 21... Amplifier section, 22... Sound source section,
23...control unit. I (University of Science, Ishikawa, Figure 2, Figure 1, Figure 7)
Claims (1)
音源からの入力信号を振幅変調や増幅して出力信号を出
力するための回路から構成される超指向性スピーカーシ
ステムにおいて、超指向性スピーカーから音声と一緒に
発信される超音波が超指向性スピーカー前方の視聴者等
から反射する超音波を受信する受信装置と、受信した超
音波の信号を処理することにより音源の切換えを制御す
る装置とを具備してなることを特徴とする超指向性スピ
ーカーシステム。In a super directional speaker system consisting of a super directional speaker using a parametric array and a circuit for amplitude modulating and amplifying the input signal from the sound source and outputting an output signal, the super directional speaker emits the sound from the super directional speaker. a receiving device that receives ultrasonic waves emitted by the user and reflected from a viewer, etc. in front of the superdirectional speaker; and a device that controls switching of sound sources by processing the received ultrasonic signals. A super directional speaker system that is characterized by
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1298457A JP2665007B2 (en) | 1989-11-16 | 1989-11-16 | Super directional speaker system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1298457A JP2665007B2 (en) | 1989-11-16 | 1989-11-16 | Super directional speaker system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03159400A true JPH03159400A (en) | 1991-07-09 |
| JP2665007B2 JP2665007B2 (en) | 1997-10-22 |
Family
ID=17859954
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1298457A Expired - Lifetime JP2665007B2 (en) | 1989-11-16 | 1989-11-16 | Super directional speaker system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2665007B2 (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1127774A (en) * | 1997-07-02 | 1999-01-29 | Mk Seiko Co Ltd | Parametric loudspeaker |
| JPH11164384A (en) * | 1997-11-25 | 1999-06-18 | Nec Corp | Super directional speaker and speaker drive method |
| US6445804B1 (en) | 1997-11-25 | 2002-09-03 | Nec Corporation | Ultra-directional speaker system and speaker system drive method |
| JP2005351897A (en) * | 2004-06-09 | 2005-12-22 | Pohang Eng College | Measuring device of ultrasonic distance in air using parametric array, and its method |
| US7215788B2 (en) | 1995-03-31 | 2007-05-08 | 1 . . . Limited | Digital loudspeaker |
| US7319641B2 (en) | 2001-10-11 | 2008-01-15 | 1 . . . Limited | Signal processing device for acoustic transducer array |
| US7801315B2 (en) | 2003-12-18 | 2010-09-21 | Citizen Holdings Co., Ltd. | Method and device for driving a directional speaker |
| JP2012038136A (en) * | 2010-08-09 | 2012-02-23 | Tabuchi Electric Co Ltd | Electric vehicle and travel control system therefor |
| JP2012056340A (en) * | 2010-09-06 | 2012-03-22 | Tabuchi Electric Co Ltd | Parametric speaker device and vehicle having the same |
| JP2012156780A (en) * | 2011-01-26 | 2012-08-16 | Nec Casio Mobile Communications Ltd | Electronic device |
| CN103713283A (en) * | 2013-12-18 | 2014-04-09 | 中国船舶重工集团公司第七二六研究所 | Method for realizing arraying of parametric receiving array |
-
1989
- 1989-11-16 JP JP1298457A patent/JP2665007B2/en not_active Expired - Lifetime
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7215788B2 (en) | 1995-03-31 | 2007-05-08 | 1 . . . Limited | Digital loudspeaker |
| JPH1127774A (en) * | 1997-07-02 | 1999-01-29 | Mk Seiko Co Ltd | Parametric loudspeaker |
| JPH11164384A (en) * | 1997-11-25 | 1999-06-18 | Nec Corp | Super directional speaker and speaker drive method |
| US6445804B1 (en) | 1997-11-25 | 2002-09-03 | Nec Corporation | Ultra-directional speaker system and speaker system drive method |
| US6678381B1 (en) | 1997-11-25 | 2004-01-13 | Nec Corporation | Ultra-directional speaker |
| US7319641B2 (en) | 2001-10-11 | 2008-01-15 | 1 . . . Limited | Signal processing device for acoustic transducer array |
| US7801315B2 (en) | 2003-12-18 | 2010-09-21 | Citizen Holdings Co., Ltd. | Method and device for driving a directional speaker |
| JP2005351897A (en) * | 2004-06-09 | 2005-12-22 | Pohang Eng College | Measuring device of ultrasonic distance in air using parametric array, and its method |
| JP4504257B2 (en) * | 2004-06-09 | 2010-07-14 | 學校法人浦項工科大學校 | Apparatus and method for measuring ultrasonic distance in air using parametric array |
| JP2012038136A (en) * | 2010-08-09 | 2012-02-23 | Tabuchi Electric Co Ltd | Electric vehicle and travel control system therefor |
| JP2012056340A (en) * | 2010-09-06 | 2012-03-22 | Tabuchi Electric Co Ltd | Parametric speaker device and vehicle having the same |
| JP2012156780A (en) * | 2011-01-26 | 2012-08-16 | Nec Casio Mobile Communications Ltd | Electronic device |
| CN103713283A (en) * | 2013-12-18 | 2014-04-09 | 中国船舶重工集团公司第七二六研究所 | Method for realizing arraying of parametric receiving array |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2665007B2 (en) | 1997-10-22 |
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