JPH0722985A - Transmission line with transmission loss compensating circuit - Google Patents
Transmission line with transmission loss compensating circuitInfo
- Publication number
- JPH0722985A JPH0722985A JP18893693A JP18893693A JPH0722985A JP H0722985 A JPH0722985 A JP H0722985A JP 18893693 A JP18893693 A JP 18893693A JP 18893693 A JP18893693 A JP 18893693A JP H0722985 A JPH0722985 A JP H0722985A
- Authority
- JP
- Japan
- Prior art keywords
- band
- transmission
- transmission loss
- input
- pass
- 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
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- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
- Bidirectional Digital Transmission (AREA)
- Dc Digital Transmission (AREA)
- Transmission Systems Not Characterized By The Medium Used For Transmission (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は，電話回線などの伝送路
における伝送損失を補償するための回路に関するもので
ある。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit for compensating for transmission loss in a transmission line such as a telephone line.
【０００２】[0002]
【従来の技術】電話回線において双方向で通話をするた
めには，本来一対の信号線を用いればよいが，回線の伝
送損失が有るために増幅器を挿入して，音声信号を増幅
して損失を補償する必要がある。ところが，１つの増幅
器で双方向の伝送損失を補償することは不可能なため，
図２に示すように片方向毎に増幅器３及び７を挿入し，
双方向の通話ができるようにしている。ところが，この
増幅器３及び７のゲインは，伝送損失が補償されるよう
に，つまり，受信する側で損失がないように設定する必
要があるので，使用する伝送回線の伝送損失が大きい場
合，非常に高いゲインに設定しなければならない。2. Description of the Related Art In order to make a two-way call on a telephone line, a pair of signal lines should originally be used. However, since there is transmission loss in the line, an amplifier is inserted to amplify a voice signal and cause loss. Need to compensate. However, it is not possible to compensate for transmission loss in both directions with a single amplifier.
Insert the amplifiers 3 and 7 in each direction as shown in FIG.
Two-way calling is possible. However, it is necessary to set the gains of the amplifiers 3 and 7 so that the transmission loss is compensated, that is, there is no loss at the receiving side. Must be set to a high gain.
【０００３】２線／４線変換ハイブリッド回路（以下Ｈ
ＹＢと呼ぶ）５では，増幅器３からの出力信号を入出力
端６の方向にだけ出力して，理論的には増幅器７へ信号
の漏洩がないようにしている。また，入出力端６からの
信号は，増幅器３へは出力されず，増幅器７にのみ出力
される。同様に，ＨＹＢ２についても，理論的には入出
力端１からの信号を増幅器３にのみ出力し，増幅器７か
らの信号を入出力端１にのみ出力する。2-wire / 4-wire conversion hybrid circuit (hereinafter referred to as H
In YB) 5, the output signal from the amplifier 3 is output only in the direction of the input / output terminal 6 so that theoretically no signal leaks to the amplifier 7. Further, the signal from the input / output terminal 6 is not output to the amplifier 3 but is output only to the amplifier 7. Similarly, for the HYB 2, theoretically, the signal from the input / output terminal 1 is output only to the amplifier 3 and the signal from the amplifier 7 is output only to the input / output terminal 1.
【０００４】[0004]
【発明が解決しようとする課題】ところが，現実には上
記ＨＹＢで若干量の漏洩が発生する。例えば，ＨＹＢ２
では増幅器７からの信号が増幅器３に漏洩し，同様に，
ＨＹＢ５では増幅器３からの信号が増幅器７に漏洩す
る。この漏洩を０あるいは極小にすることは現実上困難
である。したがって，このＨＹＢ２及び５の漏洩によ
り，使用する伝送回線の損失が大きく増幅器３，７のゲ
インが高いとき，２つの増幅器３，７とＨＹＢ２，５で
形成される内部ループのゲインが０ｄＢ以上となる場合
がある。そうすると，上記内部ループ回路は不安定状態
となり，発振現象を起こす等の不具合が発生するため，
実用にはならなくなる問題を有していた。However, in reality, a slight amount of leakage occurs in the HYB. For example, HYB2
Then, the signal from the amplifier 7 leaks to the amplifier 3, and similarly,
In HYB5, the signal from amplifier 3 leaks to amplifier 7. It is practically difficult to reduce this leakage to zero or minimize it. Therefore, when the loss of the transmission line used is large and the gains of the amplifiers 3 and 7 are high due to the leakage of the HYBs 2 and 5, the gain of the inner loop formed by the two amplifiers 3 and 7 and the HYBs 2 and 5 is 0 dB or more. May be. Then, the above-mentioned internal loop circuit becomes unstable and problems such as oscillation phenomenon occur.
It had a problem that it became impractical.
【０００５】そのため，発振現象が発生しないように増
幅器３，７のゲインを下げて使用しなければならない。
つまり，増幅器３，７のゲインは，内部ループのゲイン
が０ｄＢ以下の設定にしなければならないという制限が
ある。そうすると伝送損失が大きい場合，十分に該伝送
損失を補償できなくなり，受信側では相手の声が小さく
なり，聞こえ難い状態となる。また，ループ内もしくは
その先に接続された遠端で発生したエコーが増幅されて
しまうという問題も有していた。Therefore, the gains of the amplifiers 3 and 7 must be lowered so that the oscillation phenomenon does not occur.
That is, the gains of the amplifiers 3 and 7 have a limitation that the gain of the inner loop must be set to 0 dB or less. Then, when the transmission loss is large, the transmission loss cannot be compensated sufficiently, and the voice of the other party becomes small on the receiving side, making it difficult to hear. There is also a problem that the echo generated at the far end connected in the loop or beyond is amplified.
【０００６】本発明は上記の問題に鑑み，補償すべき伝
送損失が大きい場合でも，安定かつ確実に伝送損失を補
償し，さらにエコーをも阻止できる伝送損失補償回路を
備えた伝送路を提供することを目的とする。In view of the above problems, the present invention provides a transmission line equipped with a transmission loss compensating circuit capable of stably and reliably compensating the transmission loss even when the transmission loss to be compensated is large, and further preventing echo. The purpose is to
【０００７】[0007]
【課題を解決するための手段】本発明は上記の目的を達
成するため，上記２つの増幅器の前段または後段に，た
とえば，くし形フィルタのように複数の通過帯域を有す
る帯域通過フィルタを各々挿入する。また，各々の帯域
通過フィルタは，図３（ａ）（ｂ）に示すように通過帯
域と阻止帯域が互いに逆傾向となるような周波数特性を
有するものである。In order to achieve the above object, the present invention inserts a band pass filter having a plurality of pass bands, such as a comb filter, before or after the two amplifiers. To do. Further, each of the band pass filters has a frequency characteristic such that the pass band and the stop band have opposite tendencies as shown in FIGS. 3 (a) and 3 (b).
【０００８】すなわち，入力された音声信号に対し所定
の伝送損失を補償する第１の増幅手段と，該第１の増幅
手段と反対の伝送方向から入力された音声信号に対し所
定の伝送損失を補償する第２の増幅手段と，前記第１の
増幅手段の出力端と第２の増幅手段の入力端に接続され
２線／４線の線路変換を行う第１の変換手段と，前記第
１の増幅手段の入力端と第２の増幅手段の出力端に接続
され２線４線の線路変換を行う第２の変換手段とを含む
伝送損失補償回路を備えた伝送路において，前記第１の
増幅手段の入力端もしくは出力端に接続され音声帯域内
に複数の通過帯域と阻止帯域とを交互に配置した第１の
帯域通過フィルタと，前記第２の増幅手段の入力端もし
くは出力端に接続され音声帯域内に複数の通過帯域と阻
止帯域とを交互に配置した第２の帯域通過フィルタとを
設け，該第１の帯域通過フィルタと第２の帯域通過フィ
ルタは，上記通過帯域と阻止帯域の周波数配置が互いに
逆傾向となるような周波数特性を有するようにしたもの
である。That is, the first amplifying means for compensating a predetermined transmission loss for the input voice signal, and the predetermined transmission loss for the voice signal input from the transmission direction opposite to the first amplifying means. Compensating second amplifying means, first converting means connected to the output end of the first amplifying means and the input end of the second amplifying means for performing line conversion of 2 lines / 4 lines, and the first converting unit. In a transmission line including a transmission loss compensating circuit including a second conversion unit that is connected to an input end of the amplification unit and an output end of the second amplification unit and performs line conversion of two lines and four lines. A first bandpass filter connected to an input terminal or an output terminal of the amplifying means and having a plurality of pass bands and a stop band alternately arranged in a voice band, and connected to an input terminal or an output terminal of the second amplifying means. Alternating multiple passbands and stopbands within the voice band A second band-pass filter disposed therein, and the first band-pass filter and the second band-pass filter have frequency characteristics such that the frequency arrangements of the pass band and the stop band are opposite to each other. It is the one.
【０００９】[0009]
【作用】その結果，大きな伝送損失を補償するために各
増幅器のゲインを上げても，各ＨＹＢで漏洩した信号は
互いに漏洩側の帯域通過フィルタによって阻止されるた
め，ループゲインは０ｄＢ以下となり，内部ループ回路
は常に安定であるため，発振現象などの不具合も発生し
ない。また，同様にエコーについても，各方向で通過帯
域が異なるので確実に阻止される。As a result, even if the gain of each amplifier is increased in order to compensate for a large transmission loss, the signals leaked at each HYB are blocked by the bandpass filters on the leak side, so that the loop gain becomes 0 dB or less, Since the internal loop circuit is always stable, problems such as oscillation do not occur. Similarly, echoes are reliably blocked because the passbands differ in each direction.
【００１０】[0010]
【実施例】以下，この発明の一実施例を図１により説明
する。入出力端１から入力された音声信号はＨＹＢ２を
通過し，増幅器３に入力される。伝送回線で減衰した音
声信号は該増幅器３で増幅され，伝送損失の補償が行わ
れる。この増幅器３の出力信号は周波数特性が例えば図
３（ａ）に示した周波数特性を持つ帯域通過フィルタ４
により，制限された周波数帯域の信号のみがＨＹＢ５に
入力されて入出力端６に出力される。増幅器３のゲイン
はこの入出力端６での信号電力と入出力端１での信号電
力とが同じになるように設定する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIG. The audio signal input from the input / output terminal 1 passes through the HYB 2 and is input to the amplifier 3. The voice signal attenuated in the transmission line is amplified by the amplifier 3 and the transmission loss is compensated. The output signal of the amplifier 3 has a frequency characteristic, for example, the bandpass filter 4 having the frequency characteristic shown in FIG.
Thus, only the signal in the limited frequency band is input to the HYB 5 and output to the input / output terminal 6. The gain of the amplifier 3 is set so that the signal power at the input / output terminal 6 is the same as the signal power at the input / output terminal 1.
【００１１】また逆方向からの入出力端６から入力され
た音声信号はＨＹＢ５を通過し増幅器７に入力される。
増幅器７によって増幅された音声信号は，例えば図３
（ｂ）に示したような周波数特性を有する帯域通過フィ
ルタ８により帯域制限される。この帯域通過特性は上記
帯域通過フィルタ４の周波数特性と比較して，通過帯域
と阻止帯域の周波数配置が丁度逆になっている。この帯
域通過フィルタ８の通過信号はＨＹＢ２に入力され，入
出力端１に出力される。この場合も同様にこの出力端１
で入出力端６と同じ信号電力になるように設定する。The voice signal input from the input / output terminal 6 in the opposite direction passes through the HYB 5 and is input to the amplifier 7.
The audio signal amplified by the amplifier 7 is, for example, as shown in FIG.
The band is limited by the bandpass filter 8 having the frequency characteristic shown in FIG. In this band pass characteristic, the frequency arrangement of the pass band and the stop band is just opposite to that of the frequency characteristic of the band pass filter 4. The pass signal of the band pass filter 8 is input to the HYB 2 and output to the input / output terminal 1. In this case as well, this output end 1
Then, the signal power is set to be the same as that of the input / output terminal 6.
【００１２】ＨＹＢ２，増幅器３，帯域通過フィルタ
４，ＨＹＢ５，増幅器７，帯域通過フィルタ８で形成さ
れる内部ループのループゲインについて，帯域通過フィ
ルタ４と帯域通過フィルタ８の各々の周波数特性の通過
帯域と阻止帯域とが逆特性になっているため，例えば帯
域通過フィルタ４の通過帯域信号が増幅器７で大きく増
幅されても，帯域通過フィルタ８では，その帯域は阻止
帯域になっているため，その帯域の内部ループゲインは
ほとんど０，すなわち−∞ｄＢに近い値となり全く安定
である。Regarding the loop gain of the internal loop formed by the HYB2, the amplifier 3, the bandpass filter 4, the HYB5, the amplifier 7, and the bandpass filter 8, the passbands of the frequency characteristics of the bandpass filter 4 and the bandpass filter 8 are shown. And the stop band have opposite characteristics, for example, even if the pass band signal of the band pass filter 4 is greatly amplified by the amplifier 7, in the band pass filter 8, that band is the stop band. The inner loop gain of the band is almost 0, that is, a value close to −∞ dB, which is quite stable.
【００１３】また，帯域通過フィルタ８の通過帯域信号
が増幅器３で大きく増幅されても，帯域通過フィルタ４
では，その帯域は阻止帯域になっているため，その帯域
の内部ループゲインは同様にほとんど０に近い値となっ
て同様に全く安定である。したがって，音声帯域の全帯
域で内部ループゲインは０に近い値となって内部ループ
では安定に動作して，発信現象などの不具合を起こすこ
とはない。Further, even if the pass band signal of the band pass filter 8 is greatly amplified by the amplifier 3, the band pass filter 4
Then, since that band is the stop band, the inner loop gain of that band is also a value close to 0, and is completely stable as well. Therefore, the inner loop gain becomes a value close to 0 in the entire voice band and operates stably in the inner loop without causing a trouble such as a transmission phenomenon.
【００１４】次に，エコーについて説明する。まず，エ
コーというのは，入力端１からの音声信号がＨＹＢ５で
増幅器７側に漏洩した信号であったり，あるいは出力端
６から先に接続された回線もしくは回路から，その音声
信号が戻ってくる信号である。もともと入出力端１から
の音声信号は帯域通過フィルタ４を通過するため，図３
（ａ）と同様の周波数特性を持つ音声信号のみが通過す
る。ＨＹＢ５で漏洩した信号もしくは入出力端６から先
に接続された回線もしくは回路から戻ってくる信号は，
増幅器７によって増幅されるが，図３（ａ）の周波数特
性の音声信号のため，これらの成分は帯域通過フィルタ
８によって阻止されて，帯域通過フィルタ８以降には出
力されないので，エコーは発生しない。Next, the echo will be described. First, an echo is a signal in which an audio signal from the input terminal 1 leaks to the amplifier 7 side at the HYB 5, or the audio signal is returned from a line or circuit previously connected from the output terminal 6. It is a signal. Since the audio signal from the input / output terminal 1 originally passes through the band pass filter 4,
Only an audio signal having the same frequency characteristic as in (a) passes. The signal leaked at HYB5 or the signal returned from the line or circuit previously connected from input / output terminal 6 is
Although amplified by the amplifier 7, these components are blocked by the bandpass filter 8 and not output after the bandpass filter 8 due to the audio signal having the frequency characteristic shown in FIG. 3A, so no echo is generated. .
【００１５】帯域通過フィルタ４，８の周波数特性は，
それぞれが上で述べたものと逆でもよいし，また必ずし
もくし形フィルタのように等間隔に通過帯域と阻止帯域
が交互配置された周波数特性のフィルタでなくてもよ
い。要するに，２つの帯域通過フィルタの通過帯域と阻
止帯域とが互いに逆傾向の周波数配置となっていればよ
い。また，帯域通過フィルタも増幅器３，７の各々前段
に設置してもよいし，後段に設置しても原理的には同様
の効果を生む。The frequency characteristics of the band pass filters 4 and 8 are
Each of them may be the reverse of that described above, or may not necessarily be a filter having frequency characteristics in which pass bands and stop bands are alternately arranged at equal intervals such as a comb filter. In short, it suffices that the passbands and stopbands of the two bandpass filters have frequency arrangements that tend to be opposite to each other. Further, the bandpass filter may be installed in the front stage of each of the amplifiers 3 and 7, or may be installed in the rear stage, and in principle, the same effect is produced.
【００１６】図４は本発明の他の実施例を示す図であ
る。図において，９〜１２，１４〜１７は帯域通過フィ
ルタであり１３，１８は加算器である。また，図１と同
一部分は同一符号を用いている。帯域通過フィルタ９〜
１２及び１４〜１７は，各々単一でかつ互いに異なる通
過周波数帯域を有している。この実施例に示すように，
通過帯域の異なる複数の帯域フィルタ９〜１２，１４〜
１７を組み合わせ，各フィルタの出力を加算器１３およ
び１８でそれぞれ加算するよう構成することによって，
前記図３（ａ）及び（ｂ）に示す周波数配置のフィルタ
を実現することも可能である。FIG. 4 is a diagram showing another embodiment of the present invention. In the figure, 9 to 12 and 14 to 17 are band pass filters, and 13 and 18 are adders. The same parts as those in FIG. 1 are designated by the same reference numerals. Band pass filter 9 ~
12 and 14 to 17 each have a single and different pass frequency band. As shown in this example,
A plurality of band filters 9-12, 14- having different pass bands
By combining 17 and configuring the outputs of the filters to be added by the adders 13 and 18, respectively,
It is also possible to realize the filter having the frequency arrangement shown in FIGS. 3 (a) and 3 (b).
【００１７】本発明では，音声信号を帯域通過フィルタ
を通過させることによって，全帯域を通過させた場合よ
りも多少の音質の劣化はあるものの，実用上は全く問題
のない通話が可能である。図３においては，本発明の構
成をより簡明に説明するために，３００〜３４００Ｈｚ
の音声帯域の中で４つの通過帯域が配置される例を示し
たが，この通過帯域数を（例えば１００程度に）増や
し，図１に示した帯域通過フィルタ４及び８の両方で，
ホルマントなど音声品質を特徴づける重要な周波数成分
を抽出できる程度に音声帯域を細分化すれば，より実用
に適した伝送品質の補償回路を実現することができる。According to the present invention, a voice signal is passed through a band-pass filter, and although the sound quality is slightly deteriorated as compared with the case where the entire band is passed, practically no problem is achievable. In FIG. 3, in order to explain the configuration of the present invention more simply, 300 to 3400 Hz
The example in which four pass bands are arranged in the voice band of is shown, but the number of pass bands is increased (for example, to about 100), and both of the band pass filters 4 and 8 shown in FIG.
If the voice band is subdivided to the extent that important frequency components that characterize voice quality such as formants can be extracted, a more practical transmission quality compensation circuit can be realized.
【００１８】また，以上の実施例では，線路数の変換手
段として２線／４線変換ハイブリッド回路の例を示した
が，本発明が他の線路数の変換手段を備えた伝送路でも
適用できることは明らかである。Further, in the above embodiments, the example of the 2-wire / 4-wire conversion hybrid circuit is shown as the means for converting the number of lines, but the present invention can be applied to the transmission line provided with the means for converting other numbers of lines. Is clear.
【００１９】[0019]
【発明の効果】以上述べた如く，本発明によれば伝送損
失の補償を安定かつ確実に行なうことができて，良好な
通話品質が確保できる。また，エコーも同時に阻止をす
ることができる。例えば，図５に示すような公衆回線と
専用線を相互接続する場合において，専用線の伝送損失
だけではなく，両端の公衆回線においても発生する全体
の大きな伝送損失をも補償できる。公衆回線の伝送損失
は２５ｄＢ以上になることがある。公衆回線の場合に
は，接続先により，また同じ接続先でも接続ルートの相
違により伝送損失が異なるので，伝送損失の最も大きな
場合に合わせて，増幅器のゲインの設定をしておかなけ
ればならず，このような場合に本発明は特に大きな効果
がある。As described above, according to the present invention, the compensation of the transmission loss can be performed stably and surely, and the good communication quality can be secured. Also, echo can be blocked at the same time. For example, when the public line and the private line as shown in FIG. 5 are interconnected, not only the transmission loss of the private line but also the large total transmission loss occurring in the public lines at both ends can be compensated. The transmission loss of the public line may be 25 dB or more. In the case of a public line, the transmission loss differs depending on the connection destination, and even at the same connection destination due to the difference in the connection route. Therefore, the gain of the amplifier must be set according to the case of the largest transmission loss. In such a case, the present invention has a particularly great effect.
【図１】本発明の一実施例の構成を示すブロック図。FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.
【図２】従来の構成を示すブロック図。FIG. 2 is a block diagram showing a conventional configuration.
【図３】本発明の帯域通過フィルタの周波数特性の一例
を示す図。FIG. 3 is a diagram showing an example of frequency characteristics of a bandpass filter of the present invention.
【図４】本発明の他の実施例の構成を示すブロック図。FIG. 4 is a block diagram showing the configuration of another embodiment of the present invention.
【図５】本発明の適用例を説明するための図。FIG. 5 is a diagram for explaining an application example of the present invention.
２，５ ２線／４線変換ハイブリッド回路 ３，７ 増幅器 ４，８ 帯域通過フィルタ（くし形フィルタ） ９，１０，１１，１２，１４，１５，１６，１７ 帯域
通過フィルタ １３，１８ 加算器2,5 2-wire / 4-wire conversion hybrid circuit 3,7 Amplifier 4,8 Bandpass filter (comb filter) 9,10,11,12,14,15,16,17 Bandpass filter 13,18 Adder
Claims (3)
続された線路変換手段と，該変換手段に接続された一対
の信号線と，該一対の信号線のそれぞれに第１と第２の
帯域通過フィルタおよび第１と第２の増幅手段が挿入さ
れると共に，該第１と第２の帯域通過フィルタの通過帯
域特性が互いに逆傾向の周波数特性であることを特徴と
する伝送損失補償回路を備えた伝送路。1. An input / output signal terminal, a line conversion means connected to each of the terminals, a pair of signal lines connected to the conversion means, and a pair of first and second signal lines respectively. A transmission loss compensating circuit in which a bandpass filter and first and second amplifying means are inserted, and the passband characteristics of the first and second bandpass filters are frequency characteristics of mutually opposite tendencies. A transmission line equipped with.
償する第１の増幅手段と，該第１の増幅手段と反対の伝
送方向から入力された音声信号に対し所定の伝送損失を
補償する第２の増幅手段と，前記第１の増幅手段の出力
端と第２の増幅手段の入力端に接続され２線／４線の線
路変換を行う第１の変換手段と，前記第１の増幅手段の
入力端と第２の増幅手段の出力端に接続され２線／４線
の線路変換を行う第２の変換手段とを含む伝送損失補償
回路を備えた伝送路において， 前記第１の増幅手段の入力端もしくは出力端に接続され
音声帯域内に複数の通過帯域と阻止帯域とを交互に配置
した第１の帯域通過フィルタと，前記第２の増幅手段の
入力端もしくは出力端に接続され音声帯域内に複数の通
過帯域と阻止帯域とを交互に配置した第２の帯域通過フ
ィルタとを具備し， 前記第１の帯域通過フィルタと第２の帯域通過フィルタ
は，前記通過帯域と阻止帯域の周波数配置が互いに逆傾
向の周波数特性を有することを特徴とする伝送損失補償
回路を備えた伝送路。2. A first amplifying means for compensating a predetermined transmission loss for an input voice signal, and a predetermined transmitting loss for a voice signal inputted from a transmission direction opposite to the first amplifying means. Second amplifying means, first converting means connected to an output end of the first amplifying means and an input end of the second amplifying means for performing line conversion of 2 lines / 4 lines, and the first amplifying unit In a transmission line provided with a transmission loss compensating circuit including a second conversion means connected to an input end of the means and an output end of the second amplification means for performing line conversion of 2/4 lines, the first amplification A first bandpass filter connected to the input terminal or output terminal of the means and having a plurality of passbands and stopbands alternately arranged in the voice band; and connected to the input terminal or output terminal of the second amplifying means A second arrangement in which a plurality of pass bands and stop bands are alternately arranged in the voice band A transmission loss compensation, comprising: a band pass filter, wherein the first band pass filter and the second band pass filter have frequency characteristics in which the frequency arrangements of the pass band and the stop band are opposite to each other. A transmission line equipped with a circuit.
を備えた伝送路において，前記第１の帯域通過フィルタ
及び第２の帯域通過フィルタは，各々異なる周波数帯域
を有する複数の帯域通過フィルタと，該複数の帯域通過
フィルタの出力を加算する加算手段とで構成されること
を特徴とする伝送損失補償回路を備えた伝送路。3. A transmission line provided with the transmission loss compensation circuit according to claim 2, wherein the first band-pass filter and the second band-pass filter have a plurality of band-pass filters each having a different frequency band. And a transmission means for adding the outputs of the plurality of band pass filters.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18893693A JPH0722985A (en) | 1993-07-01 | 1993-07-01 | Transmission line with transmission loss compensating circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18893693A JPH0722985A (en) | 1993-07-01 | 1993-07-01 | Transmission line with transmission loss compensating circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0722985A true JPH0722985A (en) | 1995-01-24 |
Family
ID=16232495
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18893693A Pending JPH0722985A (en) | 1993-07-01 | 1993-07-01 | Transmission line with transmission loss compensating circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0722985A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100372158B1 (en) * | 1999-03-04 | 2003-02-14 | 류승호 | Repeater for half duplex communication using exclusive circuit |
| JP5051235B2 (en) * | 2007-10-12 | 2012-10-17 | 富士通株式会社 | Echo suppression system, echo suppression method, echo suppression program, echo suppression device, and sound output device |
| US8340963B2 (en) | 2007-10-12 | 2012-12-25 | Fujitsu Limited | Echo suppressing system, echo suppressing method, recording medium, echo suppressor, sound output device, audio system, navigation system and mobile object |
-
1993
- 1993-07-01 JP JP18893693A patent/JPH0722985A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100372158B1 (en) * | 1999-03-04 | 2003-02-14 | 류승호 | Repeater for half duplex communication using exclusive circuit |
| JP5051235B2 (en) * | 2007-10-12 | 2012-10-17 | 富士通株式会社 | Echo suppression system, echo suppression method, echo suppression program, echo suppression device, and sound output device |
| US8340963B2 (en) | 2007-10-12 | 2012-12-25 | Fujitsu Limited | Echo suppressing system, echo suppressing method, recording medium, echo suppressor, sound output device, audio system, navigation system and mobile object |
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