JPH0637931A - Multiplex transmitter - Google Patents
Multiplex transmitterInfo
- Publication number
- JPH0637931A JPH0637931A JP19231392A JP19231392A JPH0637931A JP H0637931 A JPH0637931 A JP H0637931A JP 19231392 A JP19231392 A JP 19231392A JP 19231392 A JP19231392 A JP 19231392A JP H0637931 A JPH0637931 A JP H0637931A
- Authority
- JP
- Japan
- Prior art keywords
- signal
- transmission
- filter
- voice
- frequency band
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、伝送路の所定周波数帯
域内で音声信号およびデジタルデータなどの変調信号を
同時に伝送する多重伝送装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiplex transmission device for simultaneously transmitting a voice signal and a modulated signal such as digital data within a predetermined frequency band of a transmission line.
【０００２】[0002]
【従来の技術】従来、電話回線等の端末機器において、
１回線のみを使用して音声、デジタルデータ等の複数の
信号を同時に伝送する多重伝送方式が知られている。例
えば、有線、無線通信においてデジタルデータを伝送し
ながらその内容についても同時に会話できるようにする
ことができる。この多重伝送方式を行うために従来、周
波数分割方式を使用して低周波数帯域側を音声、高周波
数帯域側をデジタルデータ等を伝送するモデム等に振り
分けていた。2. Description of the Related Art Conventionally, in terminal equipment such as telephone lines,
A multiplex transmission system is known in which a plurality of signals such as voice and digital data are simultaneously transmitted using only one line. For example, while transmitting digital data in wired or wireless communication, it is possible to simultaneously talk about the content thereof. In order to perform this multiplex transmission method, conventionally, a frequency division method has been used to distribute the low frequency band side to voice and the high frequency band side to a modem or the like for transmitting digital data.
【０００３】即ち、有線伝送路の周波数帯域は電話にお
いては０．３〜３．４ＫＨｚと狭く、音声と他の変調信
号を多重伝送する場合、図３に示すように音声信号を
０．３〜２ＫＨｚの低周波数帯域側に、変調信号を２．
５〜３．４ＫＨｚの高周波数帯域側に振り分けている。That is, the frequency band of the wired transmission line is as narrow as 0.3 to 3.4 KHz in a telephone, and when multiplex transmission of voice and other modulated signals is performed, voice signals of 0.3 to 3.4 KHz are transmitted as shown in FIG. The modulation signal is 2. on the low frequency band side of 2 KHz.
It is distributed to the high frequency band side of 5 to 3.4 KHz.
【０００４】図４は従来の多重伝送装置の構成のブロッ
ク図を示している。図４においてマイクロホン１によっ
て電気信号に変換された音声信号は増幅器（ＡＭＰ）２
によって増幅され、高域フイルタ（ＨＰＦ）３において
０．３ＫＨｚ以下の音声信号は遮断され、次に低域フイ
ルタ（ＬＰＦ）４において２．０ＫＨｚ以上の周波数帯
域は遮断されて加算器５に入力される。FIG. 4 shows a block diagram of a configuration of a conventional multiplex transmission device. In FIG. 4, a voice signal converted into an electric signal by the microphone 1 is an amplifier (AMP) 2
The audio signal of 0.3 KHz or less is cut off in the high-pass filter (HPF) 3, and the frequency band of 2.0 KHz or more is cut off in the low-pass filter (LPF) 4 and input to the adder 5. It
【０００５】また、外部からのデジタルデータはＣＰＵ
６に送られ、その出力は周波数変位変調（ＦＳＫ）回路
７によって低速度で変調され、この変調出力は高域フイ
ルタ８、低域フイルタ９に順次送られて２．５〜３．４
ＫＨｚの周波数帯域を通過した変調信号が加算器５に入
力される。Digital data from the outside is stored in the CPU.
6, the output is modulated at a low speed by a frequency displacement modulation (FSK) circuit 7, and this modulated output is sequentially sent to a high frequency filter 8 and a low frequency filter 9 and 2.5 to 3.4.
The modulated signal that has passed the frequency band of KHz is input to the adder 5.
【０００６】加算器５は各フイルタ３、４を介して制限
された０．３〜２ＫＨｚの音声信号、外部からのデジタ
ルデータに対応する２．５〜３．４ＫＨｚの変調信号を
加算して多重化し、同時にハイブリッド回路１０、電話
回線からなる伝送回路１１を介して送出される。The adder 5 adds the limited audio signal of 0.3 to 2 KHz through the filters 3 and 4 and the modulated signal of 2.5 to 3.4 KHz corresponding to the external digital data and multiplexes them. At the same time, it is transmitted through the hybrid circuit 10 and the transmission circuit 11 including a telephone line.
【０００７】一方、伝送路１１を介して相手側より送ら
れて来る音声信号とデジタルデータを表す変調信号との
多重信号はハイブリッド回路１０を介して受信され、高
域フイルタ１２と１３に入力される。受信された多重信
号のうち音声信号は高域フイルタ１２、低域フイルタ１
４を経て音声のみが選択され、増幅器１５を介して増幅
された後、スピーカ１６から音声出力される。また受信
された多重信号のうち高域フイルタ１３、低域フイルタ
１７を順次経てデジタルデータに対応する変調信号のみ
が選別されて周波数偏位復調回路１８によりデジタルデ
ータが弁別されＣＰＵ６を介してデジタルデータ出力さ
れる。このように、送信側から送られる音声、デジタル
データの信号は同時に周波数分割によって多重化されて
伝送路１１を介して受信側に送られ、一方、伝送路１１
を介して受信された多重信号は音声、デジタルデータに
分離されて復調される。On the other hand, a multiplexed signal of a voice signal and a modulation signal representing digital data sent from the other side via the transmission line 11 is received via the hybrid circuit 10 and input to the high frequency filters 12 and 13. It Of the received multiple signals, the audio signal is the high frequency filter 12 and the low frequency filter 1
Only the voice is selected via 4 and amplified through the amplifier 15, and then the voice is output from the speaker 16. Further, among the received multiple signals, only the modulated signal corresponding to the digital data is sequentially passed through the high band filter 13 and the low band filter 17, the digital data is discriminated by the frequency shift demodulation circuit 18, and the digital data is passed through the CPU 6. Is output. Thus, the voice and digital data signals sent from the transmission side are simultaneously multiplexed by frequency division and sent to the reception side via the transmission line 11, while the transmission line 11 is transmitted.
The multiplex signal received via is separated into voice and digital data and demodulated.
【０００８】[0008]
【発明が解決しょうとする課題】図３に示すように多重
伝送をする場合、音声の周波数伝送帯域とモデム等から
のデジタルデータに対応する変調信号の周波数伝送帯域
はフィルタにより区分されている。このため多重伝送さ
れる音声の明瞭度および了解度の音声の品質は使用され
るフィルタの特性により制限される。例えば、図３に示
すように音声の周波数伝送帯域を０．３〜２ＫＨｚに制
限した場合、母音の“イ”の第２フォルマントは２．４
〜３ＫＨｚにあるので伝送された音声が欠落するおそれ
がある。また、子音についても“サ”、“シ”、
“ス”、“セ”、“ソ”と発音する周波数音域は２ＫＨ
ｚ以上に主成分があるので伝送される音声が欠落し、音
声の明瞭度および了解度を大幅に悪化させる問題があっ
た。As shown in FIG. 3, in the case of multiplex transmission, a frequency transmission band of voice and a frequency transmission band of a modulation signal corresponding to digital data from a modem are separated by a filter. Therefore, the intelligibility and intelligibility of the multiplexed voice are limited by the characteristics of the filter used. For example, when the frequency transmission band of voice is limited to 0.3 to 2 KHz as shown in FIG. 3, the second formant of the vowel "a" is 2.4.
Since the frequency is up to 3 KHz, the transmitted voice may be lost. Also, for consonants, "sa", "shi",
The frequency range that pronounces "su", "se" and "so" is 2KH
Since the main component is equal to or greater than z, the transmitted voice is lost, and there is a problem that the clarity and intelligibility of the voice are significantly deteriorated.
【０００９】この発明の目的は、伝送路の所定周波数帯
域で音声、モデム等からの変調信号を同時に多重伝送す
ることができ、しかも音声信号の伝送の明瞭度および了
解度を向上を図った多重伝送装置を提供することであ
る。An object of the present invention is to enable multiplex transmission of voice, a modulated signal from a modem, etc. simultaneously in a predetermined frequency band of a transmission line, and to improve the clarity and intelligibility of the voice signal transmission. A transmission device is provided.
【００１０】[0010]
【課題を解決するための手段】本発明の多重伝送装置
は、音声信号の伝送周波数帯域を設定する第１のフイル
タ手段と、前記音声信号と多重化する前記変調信号の伝
送周波数帯域を設定する第２のフイルタ手段と、前記音
声信号を前記第１のフイルタ手段に通過させるフイルタ
側か該第１のフイルタ手段をバイパスするバイパス側か
に切換える送信側切換手段と、受信される信号を前記音
声信号の伝送周波数帯域に制限する第３のフイルタ手段
と、伝送された信号を該第３のフイルタ手段を通過させ
るフイルタ側か該第３のフイルタ手段をバイパスするバ
イパス側かに切換える受信側切換手段と、前記送信側お
よび受信側切換手段を前記音声信号のみの出力中はバイ
パス側に切換え、前記音声信号と前記変調信号の多重伝
送時には前記フイルタ側へ切換える制御手段と、を備え
て構成されている。A multiplex transmission device of the present invention sets a first filter means for setting a transmission frequency band of an audio signal and a transmission frequency band of the modulated signal to be multiplexed with the audio signal. Second filter means, transmitting side switching means for switching the filter side to a filter side for passing the audio signal to the first filter means or a bypass side for bypassing the first filter means, and a signal to be received for the audio signal Third filter means for limiting the transmission frequency band of the signal, and receiving side switching means for switching the transmitted signal between the filter side for passing through the third filter means and the bypass side for bypassing the third filter means. The transmitting side and the receiving side switching means are switched to the bypass side while outputting only the audio signal, and the file is transmitted when the audio signal and the modulated signal are multiplexed. It is configured to include a control means for switching to the side, a.
【００１１】[0011]
【作用】デジタルデータ等の変調信号を音声信号と同時
に多重化して伝送する場合には、送信側切換手段および
受信側切換手段は共にフィルタ側に切換えられ、第１の
フィルタ手段を介した音声信号と第２のフィルタ手段を
通過した変調信号とが伝送され、かつ受信される信号は
第３のフィルタ手段を介して音声信号が分離される。音
声信号のみを伝送する場合には、送信側切換手段および
受信側切換手段は共にバイパス側に切換えられ、音声信
号は第１のフィルタ手段を通過することなく伝送され、
そして受信された信号は第３のフィルタ手段を通過する
ことなく受信される。When a modulated signal such as digital data is multiplexed and transmitted at the same time as the voice signal, both the transmitting side switching means and the receiving side switching means are switched to the filter side, and the voice signal is passed through the first filter means. And the modulated signal that has passed through the second filter means are transmitted, and the received signal is separated as an audio signal via the third filter means. When transmitting only the audio signal, both the transmitting side switching means and the receiving side switching means are switched to the bypass side, and the audio signal is transmitted without passing through the first filter means,
Then, the received signal is received without passing through the third filter means.
【００１２】[0012]
【実施例】図１は本発明の多重伝送装置の一実施例を示
し、図１の構成と同一部分は同一符号を付して示し、詳
しい説明は省略する。図４の従来の構成と図１の構成と
の相違は低域フィルタ４と加算器５、低域フィルタ９と
加算器５との間に送信側切換回路２１を接続している。
送信側切換回路２１は、加算器５の入力端子を低域フィ
ルタ４と９の各出力端子に接続するフィルタ側接点ｂ
と、増幅器２から出力される音声信号をバイパス信号線
２２を介して加算器５の入力端子へと直接接続すると共
に低域フィルタ９の出力端子と加算器５の接続を遮断す
るバイパス側接点ａを備えている。一方、受信側では、
低域フィルタ１４と増幅器１５の間には受信側切換回路
２３が接続されている。この受信側切換回路２３は、低
域フィルタ１４の出力端子と増幅器１５の入力端子を接
続するフィルタ側接点ｂと、ハイブリッド回路１０を介
して受信される信号をバイパス信号線２４を介して増幅
器１５に直接導くバイパス側接点ａを備えている。FIG. 1 shows an embodiment of the multiplex transmission apparatus of the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals and their detailed description will be omitted. The difference between the conventional configuration of FIG. 4 and the configuration of FIG. 1 is that a transmission side switching circuit 21 is connected between the low-pass filter 4 and the adder 5 and between the low-pass filter 9 and the adder 5.
The transmission side switching circuit 21 has a filter side contact b for connecting the input terminal of the adder 5 to the output terminals of the low-pass filters 4 and 9.
And a bypass-side contact a that directly connects the audio signal output from the amplifier 2 to the input terminal of the adder 5 via the bypass signal line 22 and disconnects the output terminal of the low-pass filter 9 and the adder 5 from each other. Is equipped with. On the other hand, on the receiving side,
A receiving side switching circuit 23 is connected between the low pass filter 14 and the amplifier 15. The receiving-side switching circuit 23 includes a filter-side contact b that connects the output terminal of the low-pass filter 14 and the input terminal of the amplifier 15, and a signal received through the hybrid circuit 10 via the bypass signal line 24. It has a bypass side contact a that directly leads to.
【００１３】また、ＣＰＵ６には時間同期回路２５が備
えられており、該回路２５から信号線２６を介して切換
信号が送信側切換回路２１および受信側切換回路２３に
切換信号が出力される。送信側切換回路２１および受信
側切換回路２３は切換信号が入力されている間、フィル
タ側接点ｂに切換えて音声信号のフィルタリングを行
う。ＣＰＵ６は、デジタルデータが入力されると時間同
期回路２５を動作して前記切換信号を出力させると共
に、デジタルデータの入力が停止してデータの伝送が一
定時間後に終了すると時間同期回路２５からの切換信号
の出力を停止させる。Further, the CPU 6 is provided with a time synchronizing circuit 25, and a switching signal is output from the circuit 25 to the transmitting side switching circuit 21 and the receiving side switching circuit 23 via a signal line 26. The transmitting side switching circuit 21 and the receiving side switching circuit 23 switch to the filter side contact b to filter the audio signal while the switching signal is being input. When the digital data is input, the CPU 6 operates the time synchronization circuit 25 to output the switching signal, and when the input of the digital data is stopped and the data transmission ends after a certain time, the switching from the time synchronization circuit 25 is performed. Stop signal output.
【００１４】図１のように構成された多重伝送装置にお
いて、音声信号とデジタルデータを同時に伝送する場合
は、デジタルデータがＣＰＵ６に入力するから時間同期
回路２５が動作されて切換信号が出力され、送信側切換
回路２１および受信側切換回路２３はフィルタ側接点ｂ
に切換えられる。このため、音声信号は高域フィルタ
３、低域フィルタ４を順次介した図２の（Ａ）に示すよ
うな０．３〜２ＫＨｚの周波数帯域の信号が加算器５に
入力され、同時に、デジタルデータの変調信号は高域フ
ィルタ８、低域フィルタ９を順次介して加算器５に入力
されて多重化され伝送路１１に送出される。一方、伝送
路１１、ハイブリッド回路１０を介して受信される信号
は高域フィルタ１３、低域フィルタ１７、周波数偏位復
調回路１８、ＣＰＵ６を順次介してデジタルデータとし
て復調されて出力される。さらに同時に高域フィルタ１
２、低域フィルタ１４を順次介して図２の（Ａ）に示す
周波数帯域の音声信号が選択されて増幅器１５、スピー
カ１６を介して音声出力される。In the multiplex transmission device configured as shown in FIG. 1, when transmitting a voice signal and digital data at the same time, since the digital data is input to the CPU 6, the time synchronizing circuit 25 is operated to output the switching signal, The transmission side switching circuit 21 and the reception side switching circuit 23 are connected to the filter side contact b.
Is switched to. For this reason, as the audio signal, a signal in the frequency band of 0.3 to 2 KHz as shown in FIG. The modulated signal of data is input to the adder 5 through the high-pass filter 8 and the low-pass filter 9 in order, multiplexed, and sent out to the transmission line 11. On the other hand, the signal received via the transmission line 11 and the hybrid circuit 10 is demodulated as digital data and output via the high-pass filter 13, the low-pass filter 17, the frequency shift demodulation circuit 18, and the CPU 6 in sequence. At the same time, high-pass filter 1
2. The audio signal in the frequency band shown in FIG. 2A is sequentially selected through the low-pass filter 14 and output as audio through the amplifier 15 and the speaker 16.
【００１５】音声信号のみを伝送する場合は、ＣＰＵ６
へのデジタルデータの入力は停止するから時間同期回路
２５はデジタルデータの入力終了時から一定時間後に切
換信号の出力を停止する。このため、送信側切換回路２
１および受信側切換回路２３はバイパス側接点ａに切換
えられる。この状態で入力する音声信号はバイパス信号
線２２、送信側切換回路２１、加算器５をそれぞれ介し
て伝送される。この結果、音声信号は高域フィルタ３お
よび低域フィルタ４を通過することなく図２の（Ｂ）に
示すように伝送路１１の有効周波数帯域０．３〜３．４
ＫＨｚの音声信号が伝送される。一方、受信される音声
信号はバイパス信号線２４、受信側切換回路２３、増幅
器１５、スピーカ１６を順次介して図２の（Ｂ）に示す
帯域の音声が出力される。受信される音声信号は高域フ
ィルタ１２、低域フィルタ１４を通過することはない。
しかして、音声信号のみを伝送する場合には自動的に音
声伝送周波数帯域が拡大され音声の明瞭度および了解度
が向上する。When transmitting only a voice signal, the CPU 6
Since the input of the digital data to the digital signal is stopped, the time synchronization circuit 25 stops the output of the switching signal after a fixed time from the end of the input of the digital data. Therefore, the transmission side switching circuit 2
1 and the receiving side switching circuit 23 are switched to the bypass side contact a. The audio signal input in this state is transmitted via the bypass signal line 22, the transmission side switching circuit 21, and the adder 5, respectively. As a result, the audio signal does not pass through the high-pass filter 3 and the low-pass filter 4, and the effective frequency band of the transmission line 11 is 0.3 to 3.4 as shown in FIG.
A KHz audio signal is transmitted. On the other hand, as the received audio signal, the audio in the band shown in FIG. 2B is output through the bypass signal line 24, the receiving side switching circuit 23, the amplifier 15, and the speaker 16 in that order. The received audio signal does not pass through the high pass filter 12 and the low pass filter 14.
Therefore, when only a voice signal is transmitted, the voice transmission frequency band is automatically expanded, and the clarity and intelligibility of the voice are improved.
【００１６】なお、本発明は上記実施例に限定されるも
のではなく、使用されるフィルタの周波数特性は任意に
選択することができる。また多重伝送装置は双方向伝送
である必要はなく、単一方向の多重伝送装置でも良い。The present invention is not limited to the above embodiment, and the frequency characteristic of the filter used can be arbitrarily selected. Further, the multiplex transmission device need not be bidirectional transmission, and may be a unidirectional multiplex transmission device.
【００１７】[0017]
【効果】以上説明したようにこの発明は、多重伝送装置
において音声信号のみを伝送する場合には自動的に伝送
路の伝送可能な周波数帯域の限度まで音声伝送周波数帯
域を拡大することができるから音声の明瞭度および了解
度等の音声の品質を有線、無線を問はずに格段に改善す
ることができる。しかも、従来の装置に時間同期回路お
よび切換回路を追加する簡単な構成であるので安価に製
造することができる。As described above, according to the present invention, when only a voice signal is transmitted in the multiplex transmission device, the voice transmission frequency band can be automatically expanded to the limit of the frequency band in which the transmission line can transmit. It is possible to significantly improve voice quality such as intelligibility and intelligibility of voice regardless of wired or wireless. Moreover, since the time synchronization circuit and the switching circuit are simply added to the conventional device, the device can be manufactured at low cost.
【図１】本発明の一実施例を示すブロック図である。FIG. 1 is a block diagram showing an embodiment of the present invention.
【図２】図１の多重伝送装置により伝送される音声伝送
周波数帯域を示す図である。FIG. 2 is a diagram showing a voice transmission frequency band transmitted by the multiplex transmission device of FIG.
【図３】従来の多重伝送の周波数帯域区分を示す図であ
る。FIG. 3 is a diagram showing frequency band division of conventional multiplex transmission.
【図４】従来の多重伝送装置を示すブロック図である。FIG. 4 is a block diagram showing a conventional multiplex transmission device.
３、８、１２、１３ 高域フィルタ ４、９、１４、１７ 低域フィルタ ２１ 送信側切換回路 ２２、２４ バイパス回路 ２３ 受信側切換回路 ２５ 時間同期回路 3, 8, 12, 13 High-pass filter 4, 9, 14, 17 Low-pass filter 21 Transmission side switching circuit 22, 24 Bypass circuit 23 Reception side switching circuit 25 Time synchronization circuit
Claims (1)
よび変調信号を多重伝送する伝送装置において、 前記音声信号の伝送周波数帯域を設定する第１のフイル
タ手段と、前記音声信号と多重化する前記変調信号の伝
送周波数帯域を設定する第２のフイルタ手段と、前記音
声信号を前記第１のフイルタ手段に通過させるフイルタ
側か該第１のフイルタ手段をバイパスするバイパス側か
に切換える送信側切換手段と、受信される信号を前記音
声信号の伝送周波数帯域に制限する第３のフイルタ手段
と、伝送された信号を該第３のフイルタ手段を通過させ
るフイルタ側か該第３のフイルタ手段をバイパスするバ
イパス側かに切換える受信側切換手段と、前記送信側お
よび受信側切換手段を前記音声信号のみの出力中はバイ
パス側に切換え、前記音声信号と前記変調信号の多重伝
送時には前記フイルタ側へ切換える制御手段と、を備え
てなる多重伝送装置。1. A transmission device that multiplex-transmits a voice signal and a modulated signal within a predetermined frequency band of a transmission path, wherein: first filter means for setting a transmission frequency band of the voice signal, and the voice signal are multiplexed. Second filter means for setting a transmission frequency band of the modulated signal, and transmission side switching for switching to a filter side for passing the audio signal to the first filter means or a bypass side for bypassing the first filter means. Means, third filter means for limiting a received signal to a transmission frequency band of the audio signal, and a filter side for passing the transmitted signal through the third filter means or bypassing the third filter means. The receiving side switching means for switching to the bypass side and the transmitting side and the receiving side switching means are switched to the bypass side while outputting only the audio signal, Multiplex transmission apparatus at the time of multiplex transmission of signals and the modulated signal formed by and a control means for switching to the filter side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19231392A JPH0637931A (en) | 1992-07-20 | 1992-07-20 | Multiplex transmitter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19231392A JPH0637931A (en) | 1992-07-20 | 1992-07-20 | Multiplex transmitter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0637931A true JPH0637931A (en) | 1994-02-10 |
Family
ID=16289206
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19231392A Pending JPH0637931A (en) | 1992-07-20 | 1992-07-20 | Multiplex transmitter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0637931A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2161482A2 (en) | 2008-09-04 | 2010-03-10 | JATCO Ltd | Control device for vehicle and control method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54149535A (en) * | 1978-05-17 | 1979-11-22 | Mitsubishi Electric Corp | Analog-value generating element |
| JPS6218862A (en) * | 1985-07-18 | 1987-01-27 | Oki Electric Ind Co Ltd | Reception system at absent |
| JPS62260464A (en) * | 1986-05-06 | 1987-11-12 | Nec Corp | Facsimile equipment |
-
1992
- 1992-07-20 JP JP19231392A patent/JPH0637931A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54149535A (en) * | 1978-05-17 | 1979-11-22 | Mitsubishi Electric Corp | Analog-value generating element |
| JPS6218862A (en) * | 1985-07-18 | 1987-01-27 | Oki Electric Ind Co Ltd | Reception system at absent |
| JPS62260464A (en) * | 1986-05-06 | 1987-11-12 | Nec Corp | Facsimile equipment |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2161482A2 (en) | 2008-09-04 | 2010-03-10 | JATCO Ltd | Control device for vehicle and control method thereof |
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