JPS63175560A - Amplitude equalizing circuit for telephone circuit - Google Patents
Amplitude equalizing circuit for telephone circuitInfo
- Publication number
- JPS63175560A JPS63175560A JP684987A JP684987A JPS63175560A JP S63175560 A JPS63175560 A JP S63175560A JP 684987 A JP684987 A JP 684987A JP 684987 A JP684987 A JP 684987A JP S63175560 A JPS63175560 A JP S63175560A
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- characteristic
- input signal
- low
- pass circuit
- 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
- 230000004069 differentiation Effects 0.000 claims abstract 5
- 238000010586 diagram Methods 0.000 description 10
- 230000003321 amplification Effects 0.000 description 4
- 238000003199 nucleic acid amplification method Methods 0.000 description 4
- 239000003990 capacitor Substances 0.000 description 3
- 239000002131 composite material Substances 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000002123 temporal effect Effects 0.000 description 1
Landscapes
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Abstract
Description
【発明の詳細な説明】
「産業上の利用分野」
この発明は、電話回線における伝送信号の減衰を補償す
る際に用いて好適な電話回線の振幅等化回路に関する。DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a telephone line amplitude equalization circuit suitable for use in compensating for attenuation of transmission signals on a telephone line.
［−従来の技術」
周知のように、電話回線は固有の減衰特性を有している
）こめ、回線の減衰特性に応じて信号の振幅を補償する
必要がある。第５図は、このような用途に用いられる従
来の振幅等化回路の構成を示す回路図である。図におい
て、Ｉは非反転入力端が接地されている演算増幅器であ
り、その反転入力端には４種の特性付加回路２ａ〜２ｄ
が各々スイッチ５ｌ−３４を介して接続されている。特
性付加回路２λは抵抗により、また特性付加回路２ｂ〜
２ｄは各々抵抗とコンデンサの混合回路により構成され
ている。この場合、スイッチ８１〜Ｓ４のいずれか１つ
をオン状態として特性付加回路２ａ〜２ｄのいずれかを
選択する。第６図（イ）は、］、、５ＫＨｚを基準とし
た電話回線におｉｌｌる減衰量がＯｄＢ、４ｄＢ、８ｄ
Ｂ、１２ｄＢの場合の減衰特性を１．５ＫＩ（ｚをＯｄ
Ｂとしてレベルを合わせて示したものである。第６図（
ロ）は、特性付加回路２ａ〜２ｄを選択した場合の振幅
等化回路の増幅特性を示すもので、第６図（イ）の特性
を補正するものとなっている。なお、電話回線の減衰特
性は、図示のように１．５ＫＴ−１ｚを括僧として決め
られている。また、実際の減衰特性は電話局と宅内電話
を接続する加入者ケーブルの長さにより種々の傾きにな
るが、便宜上ＯｄＢ、４ｄＢ、８ｄＢ、１２ｄＢの４種
の減衰特性に代表させ、いずれかに属するものとして取
り扱っている。[-Prior Art] As is well known, telephone lines have their own attenuation characteristics, so it is necessary to compensate the amplitude of the signal in accordance with the attenuation characteristics of the line. FIG. 5 is a circuit diagram showing the configuration of a conventional amplitude equalization circuit used for such applications. In the figure, I is an operational amplifier whose non-inverting input terminal is grounded, and its inverting input terminal has four types of characteristic adding circuits 2a to 2d.
are connected to each other via switches 5l-34. The characteristic adding circuit 2λ is connected by a resistor, and the characteristic adding circuit 2b~
2d are each composed of a mixed circuit of a resistor and a capacitor. In this case, any one of the switches 81 to S4 is turned on to select one of the characteristic adding circuits 2a to 2d. Figure 6 (a) shows that the attenuation of the telephone line based on 5KHz is OdB, 4dB, and 8d.
B, the attenuation characteristic in the case of 12dB is 1.5KI (z is Od
The levels are shown together as B. Figure 6 (
B) shows the amplification characteristics of the amplitude equalization circuit when the characteristic adding circuits 2a to 2d are selected, and is used to correct the characteristics shown in FIG. 6(A). The attenuation characteristics of the telephone line are determined to be 1.5KT-1z as shown in the figure. In addition, although the actual attenuation characteristics vary depending on the length of the subscriber cable that connects the telephone office and the home telephone, for convenience, we will represent four types of attenuation characteristics: OdB, 4dB, 8dB, and 12dB. It is treated as belonging.
「発明が解決しようとする問題点」
ところで、上述した従来の電話回線の振幅等化回路にお
いては、電話回線の減衰特性に応じた特性付加回路を予
め多数具備する必要があり、構成が複雑となる欠点があ
った。また、予め設定した特性のいずれかを選択すると
いう構成であるため、利得設定が段階的にしか行えず、
各段階の中間的な特性が要求される場合等に適応できな
いという欠点があった。"Problems to be Solved by the Invention" By the way, in the above-mentioned conventional telephone line amplitude equalization circuit, it is necessary to provide in advance a large number of characteristic adding circuits according to the attenuation characteristics of the telephone line, resulting in a complicated configuration. There was a drawback. In addition, since the configuration is such that one of the preset characteristics is selected, gain settings can only be made in stages.
This method has the disadvantage that it cannot be applied to cases where intermediate characteristics at each stage are required.
この発明は上述した事情に鑑みてなされたもので、個別
の特性付加回路を多数具備する必要がなく、かつ、任意
の補償特性を得ることができる電話回線の振幅等化回路
を提供することを目的としている。The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide an amplitude equalization circuit for a telephone line that does not require a large number of individual characteristic adding circuits and can obtain arbitrary compensation characteristics. The purpose is
１問題点を解決するための手段」
この発明は、」１記問題点を解決するために、入力信号
が供給される微分回路と、前記人力信号が供給される低
域通過回路と、前記微分回路および前記低域通過回路の
出力信号を加算ずろ加算点とを具備している。Means for Solving Problem No. 1" In order to solve problem No. 1, the present invention provides a differentiating circuit to which an input signal is supplied, a low-pass circuit to which the human input signal is supplied, and a differential circuit to which the input signal is supplied. circuit and a point for adding the output signals of the low-pass circuit.
１作用 」
前記加算点に得られる信号の特性は、前記微分回路と前
記低域通過回路の各特性の和となり、各特性の関係によ
って定まる傾きて、周波数にほぼ比例して利得が増加す
る特性となる。1. The characteristic of the signal obtained at the addition point is the sum of the characteristics of the differentiating circuit and the low-pass circuit, and the gain increases approximately in proportion to the frequency with a slope determined by the relationship between the characteristics. becomes.
「実施例」
以下、図面を参照してこの発明の実施例について説明す
る。"Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings.
第１図は、この発明の一実施例の構成を示すブロック図
である。図において、５は入力端子であり、微分回路６
と低域通過回路７の各入力端に接続されている。微分回
路６および低域通過回路７は、例えば演算増幅器、抵抗
、コンデンサを用いて構成されており、内部の抵抗また
はコンデンザが可変に構成されて、回路の利得が調整し
得るようになっている。これら微分回路６と低域通過回
路７の各出力信号は、加算点８に供給されて加算される
ようになっており、この加算点８において得られる信号
が出力端子９に供給される。FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In the figure, 5 is an input terminal, and the differential circuit 6
and each input terminal of the low-pass circuit 7. The differentiating circuit 6 and the low-pass circuit 7 are configured using, for example, an operational amplifier, a resistor, and a capacitor, and the internal resistor or capacitor is configured to be variable so that the gain of the circuit can be adjusted. . The respective output signals of the differentiating circuit 6 and the low-pass circuit 7 are supplied to a summing point 8 and added thereto, and the signal obtained at the summing point 8 is supplied to an output terminal 9.
」二記構成において、微分回路６の特性が第２図（イ）
に示すような特性であり、また、低域通過回路７の特性
が同図（ロ）に示す特性であったとすると、加算点８に
得られる信号の周波数特性は、同図（ハ）に実線で示す
ように、微分回路６と低域通過回路７の周波数特性を加
え合わせた特性となり、］、５ＫＨｚを基準としたほぼ
一定の傾きを有する増幅特性となる。また、微分回路６
および低域通過回路７の特性を各々第３図（イ）、（ロ
）に示す特性とすると、その合成特性は同図（）＼）に
示す特性となり、１．５ＫＨｚを基準にし、かつ、第２
図（ハ）の場合より大きな傾きを有する増幅特性となる
。” In the configuration described above, the characteristics of the differentiating circuit 6 are as shown in Fig. 2 (a).
If the characteristics of the low-pass circuit 7 are as shown in FIG. As shown, the characteristic is a combination of the frequency characteristics of the differentiating circuit 6 and the low-pass circuit 7, and the amplification characteristic has a substantially constant slope with respect to 5 KHz. In addition, the differential circuit 6
Assuming that the characteristics of the low-pass circuit 7 and the low-pass circuit 7 are as shown in FIG. Second
The amplification characteristic has a larger slope than in the case of FIG.
そして、合成特性の傾きは、微分回路６と低域通過回路
７の利得の調整により、任意に、かつ、４一
連続的に変えることができるから、電話回線の減衰特性
に適合した利得特性とすることができろ。Since the slope of the composite characteristic can be changed arbitrarily and continuously by adjusting the gains of the differentiating circuit 6 and the low-pass circuit 7, the slope of the composite characteristic can be changed arbitrarily and continuously. Be able to do it.
なお、上記実施例において、微分回路６および低域通過
回路７を各々デジタルフィルタにより構成してもよい。In the above embodiment, the differentiating circuit 6 and the low-pass circuit 7 may each be configured by a digital filter.
ここで、第４図（イ）〜（ハ）は各々同図（ホ）に実線
で示す特性をデジタルフィルタにより実現する場合の回
路各部のインパル・レスポンスを示す図である。周知の
ように、微分回路６と低域通過回路７の特性を加算した
回路のインパルスレスポンスは、各々の回路のインパル
ス・レスポンスを時間的に加算したものとなる。Here, FIGS. 4(A) to 4(C) are diagrams showing the impulse responses of each part of the circuit when the characteristics shown by the solid lines in FIG. 4(E) are realized by a digital filter. As is well known, the impulse response of a circuit obtained by adding the characteristics of the differentiating circuit 6 and the low-pass circuit 7 is the temporal summation of the impulse responses of each circuit.
したがって、微分回路６のインパルス・レスポンスが第
４図（イ）に示す特性であり、低域通過回路７のインパ
ルス・レスポンスが第４図（ロ）に示す特性であった場
合は、加算点８におけるインパルス・レスポンスは第４
図（ハ）に示すようになる。Therefore, if the impulse response of the differentiating circuit 6 has the characteristics shown in FIG. 4 (a), and the impulse response of the low-pass circuit 7 has the characteristics shown in FIG. The impulse response in
The result is as shown in Figure (c).
また、デジタルフィルタにより構成すると、各回路のゲ
イン設定は、デジタルフィルタにおける係数を設定する
ことにより任意の値にすることがてき、その変更も極め
て容易となる利点が得られろ。Further, when configured using a digital filter, the gain setting of each circuit can be set to an arbitrary value by setting coefficients in the digital filter, and there is an advantage that the change is extremely easy.
「発明の効果」
以−Ｌ説明したように、この発明によれば、入力信号が
供給される微分回路と、前記入力信号が供給される低域
通過回路と、前記微分回路および前記低域通過回路の出
力信号を加算する加算点とを具備したので、個別の特性
付加回路を多数具備ずろ必要がなく、構成を簡単にする
ことができ、かつ、任意の補償特性を得ることができる
利点を有する。"Effects of the Invention" As explained hereafter, according to the present invention, there is provided a differentiating circuit to which an input signal is supplied, a low-pass circuit to which the input signal is supplied, and a differentiating circuit and a low-pass circuit to which the input signal is supplied. Since it is equipped with a summing point that adds the output signals of the circuit, there is no need to provide a large number of individual characteristic adding circuits, the configuration can be simplified, and it has the advantage of being able to obtain arbitrary compensation characteristics. have
第１図はこの発明の一実施例の構成を示すブロック図、
第２図および第３図は各々同実施例の特性を示す特性図
、第４図は各々同実施例をデジタルフィルタにより構成
した場合のインパルス・レスポンスを示す図、第５図は
従来の振幅等化回路の構成を示す回路図、第６図（イ）
は電話回線の減衰特性を示す特性図、第６図（ロ）は第
５図の振幅等化回路の増幅特性を示す特性図である。
＝７−
５・・・・・・入力端子、６・・・・・微分回路、７・
・・・低域通過回路、８・・・・加算点、９・・ 出力
端子。FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.
2 and 3 are characteristic diagrams showing the characteristics of the same embodiment, FIG. 4 is a diagram showing the impulse response when the same embodiment is configured with a digital filter, and FIG. 5 is a diagram showing the conventional amplitude etc. Circuit diagram showing the configuration of the conversion circuit, Figure 6 (a)
6 is a characteristic diagram showing the attenuation characteristic of the telephone line, and FIG. 6(b) is a characteristic diagram showing the amplification characteristic of the amplitude equalization circuit of FIG. =7- 5...Input terminal, 6...Differential circuit, 7...
...Low pass circuit, 8...Summing point, 9...Output terminal.
Claims (2)
が供給される低域通過回路と、前記微分回路および前記
低域通過回路の出力信号を加算する加算点とを具備する
ことを特徴とする電話回線の振幅等化回路。(1) A differentiation circuit to which an input signal is supplied, a low-pass circuit to which the input signal is supplied, and an addition point to add the output signals of the differentiation circuit and the low-pass circuit. An amplitude equalization circuit for a telephone line.
フィルタにより構成したことを特徴とする電話回線の振
幅等化回路。(2) An amplitude equalization circuit for a telephone line, characterized in that the differentiating circuit and the low-pass circuit are constructed of digital filters.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62006849A JPH082065B2 (en) | 1987-01-14 | 1987-01-14 | Telephone line amplitude equalization circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62006849A JPH082065B2 (en) | 1987-01-14 | 1987-01-14 | Telephone line amplitude equalization circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63175560A true JPS63175560A (en) | 1988-07-19 |
| JPH082065B2 JPH082065B2 (en) | 1996-01-10 |
Family
ID=11649686
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62006849A Expired - Fee Related JPH082065B2 (en) | 1987-01-14 | 1987-01-14 | Telephone line amplitude equalization circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH082065B2 (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6093831A (en) * | 1983-10-27 | 1985-05-25 | Yaesu Musen Co Ltd | Sound signal processing circuit |
| JPS60150661U (en) * | 1984-03-19 | 1985-10-07 | 三洋電機株式会社 | video tape recorder |
-
1987
- 1987-01-14 JP JP62006849A patent/JPH082065B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6093831A (en) * | 1983-10-27 | 1985-05-25 | Yaesu Musen Co Ltd | Sound signal processing circuit |
| JPS60150661U (en) * | 1984-03-19 | 1985-10-07 | 三洋電機株式会社 | video tape recorder |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH082065B2 (en) | 1996-01-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |