JPS6134701B2 - - Google Patents
Info
- Publication number
- JPS6134701B2 JPS6134701B2 JP8436980A JP8436980A JPS6134701B2 JP S6134701 B2 JPS6134701 B2 JP S6134701B2 JP 8436980 A JP8436980 A JP 8436980A JP 8436980 A JP8436980 A JP 8436980A JP S6134701 B2 JPS6134701 B2 JP S6134701B2
- Authority
- JP
- Japan
- Prior art keywords
- filter
- output
- signal
- modulator
- modulated
- 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
Links
- 230000005540 biological transmission Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 239000003990 capacitor Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
- H04B1/54—Circuits using the same frequency for two directions of communication
- H04B1/58—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa
- H04B1/581—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa using a transformer
- H04B1/582—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa using a transformer with automatic balancing
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Description
【発明の詳細な説明】 本発明はハイブリツド回路の平衡に関する。[Detailed description of the invention] The present invention relates to balancing of hybrid circuits.
４線２線の変換回路として用いられるハイブリ
ツド回路は、４線側送信信号が受信側にまわり込
む量を抑圧するために、２線側に接続される線路
インピーダンスと平衡結線網のインピーダンスと
の平衡がとられなければならない。従来、このよ
うな平衡動作は平衡回路網の抵抗を手動調整によ
り行なわれる。このため、時間と共に刻々と変化
する線路インピーダンスに対しては調整に多くの
手数と時間を要し、しかも調整中は回線の使用が
できないという欠点がある。この結果、送信側か
ら受信側へのまわり込みの抑圧が十分行なわれな
い。このため、電力線搬送装置等においては、送
信信号帯域と受信信号帯域との間に分離周波数間
隔を設け、かつ、帯域外減衰量の十分大きい送信
フイルタ、受信フイルタを使用する必要がある。
一定の周波数の信号、例えば、パイロツト信号が
伝送されている場合は、これを利用して平衡結線
網の抵抗を制御することも考えられるが、そのた
めにはパイロツト信号抽出装置等を必要とする。 A hybrid circuit used as a 4-wire 2-wire conversion circuit is designed to maintain a balance between the line impedance connected to the 2-wire side and the impedance of the balanced wiring network in order to suppress the amount of the 4-wire side transmission signal going around to the receiving side. must be taken. Conventionally, such balancing is accomplished by manually adjusting the resistance of the balancing network. For this reason, it takes a lot of effort and time to adjust the line impedance, which changes every moment with time, and the line cannot be used during the adjustment. As a result, interference from the transmitting side to the receiving side is not sufficiently suppressed. For this reason, in power line carrier devices and the like, it is necessary to provide a separation frequency interval between the transmission signal band and the reception signal band, and to use transmission filters and reception filters with sufficiently large out-of-band attenuation.
If a signal of a certain frequency, for example a pilot signal, is being transmitted, it may be possible to use this to control the resistance of the balanced wiring network, but this requires a pilot signal extraction device or the like.
本発明の目的は線路に常時送出されている周波
数偏移信号、例えば、電話機のダイヤル信号及び
フツク信号を送受するための、リンガー信号を利
用して線路インピーダンスの変化に追従して平衡
結線網の抵抗値制御を行なうことができるハイブ
リツド回路を提供することにある。 An object of the present invention is to create a balanced wiring network by following changes in line impedance using a ringer signal for transmitting and receiving frequency-shifted signals such as telephone dial signals and hook signals that are constantly sent to a line. An object of the present invention is to provide a hybrid circuit that can control resistance values.
本発明の回路は、周波数偏移信号が伝送されて
いるハイブリツド回路の４線側送信端子に並列に
接続された第１の変調器と、前記４線側受信端子
に並列に接続された第２の変調器と、前記第２の
変調器の出力の位相を反転させる位相反転回路
と、前記第２の変調器の出力と前記反転回路の出
力とを前記第１の変調器の出力信号に同期して交
互に切替えて出力する切替回路と、該切替回路の
出力の大きさと極性によつて制御される可変抵抗
とを備え、線路抵抗の変化に応答して前記可変抵
抗の抵抗値が制御され平衡がとられるようにして
いる。 The circuit of the present invention includes a first modulator connected in parallel to a four-wire side transmitting terminal of a hybrid circuit through which a frequency-shifted signal is transmitted, and a second modulator connected in parallel to the four-wire side receiving terminal. a phase inversion circuit that inverts the phase of the output of the second modulator, and synchronizes the output of the second modulator and the output of the inversion circuit with the output signal of the first modulator. and a variable resistor that is controlled by the magnitude and polarity of the output of the switching circuit, and the resistance value of the variable resistor is controlled in response to changes in line resistance. I try to maintain balance.
次に、本発明の図面を参照して詳細に説明す
る。 Next, the present invention will be explained in detail with reference to the drawings.
第１図は本発明の一実施例を示すブロツク図で
あり、送信通話電流等および周波数偏移信号は、
端子Ｓからハイブリツドコイル１を介して線路端
子Ｌへ出力される。相手局からの通話電流等は、
線路端子Ｌから入力されハイブリツドコイル１を
介して端子Ｒに送られる。この際、平衡結線網２
のインピダンスが線路インピダンスと平衡してい
れば、前記端子Ｓからの送信信号は端子Ｒへ伝達
されないが、平衡がとれていないと、その程度に
応じたまわり込み電流が端子Ｒに現われ相手局か
らの受信電流に重畳され各種の妨害作用を生じ
る。前記周波数偏移信号は、並列に第１の変調器
３に送られ端子Ｍから入力された基準周波数の変
調電流によつて変調される。前記変調器３は、本
来の周波数偏移信号の伝送を妨げないように高イ
ンピダンスであることが望ましい。また、周波数
偏移信号の周波数が、該当チヤネルの図示されな
い信号線のオンオフに対応して202.3kHzまたは
202.4kHzのいずれかであるものとすると、前記変
調電流の周波数は202.35kHzに設定される。この
結果、前記周波数偏移信号の周波数が上記二周波
数のいずれであつても第１の変調器３の出力電流
の周波数50Hzを含んでいる。 FIG. 1 is a block diagram showing an embodiment of the present invention.
The signal is output from the terminal S to the line terminal L via the hybrid coil 1. The call current etc. from the other station is
It is input from the line terminal L and sent to the terminal R via the hybrid coil 1. At this time, the balanced connection network 2
If the impedance of is balanced with the line impedance, the transmission signal from the terminal S will not be transmitted to the terminal R. However, if the impedance is not balanced, a sneak current corresponding to the degree will appear at the terminal R, and the transmission signal from the other station will be transmitted to the terminal R. It is superimposed on the received current and causes various interference effects. The frequency shift signal is sent in parallel to the first modulator 3 and is modulated by a modulation current of the reference frequency input from the terminal M. It is desirable that the modulator 3 has high impedance so as not to interfere with the transmission of the original frequency-shifted signal. Also, the frequency of the frequency shift signal is 202.3kHz or 202.3kHz, depending on whether the signal line (not shown) of the corresponding channel
202.4kHz, the frequency of the modulation current is set to 202.35kHz. As a result, no matter which of the two frequencies the frequency of the frequency shift signal is, it includes the frequency of the output current of the first modulator 3 of 50 Hz.
該50Hzの被変調波は第１のフイルタ４によつて
抽出される。一方、平衡結線網２のインピダンス
と線路インピダンスとの不平衡によつて、周波数
偏移信号の一部が受信端子Ｒ側にまわり込んでい
る。このまわり込み電流は、第２の変調器５に入
力して前記端子Ｍから入力された前記変調電流
（202.35kHz）によつて変調され、50Hzを含んだ被
変調電流となり、第２のフイルタ６を介して50Hz
のみとされる。上記第２のフイルタ６の出力電流
は、位相反転回路７を介して切替回路８に送られ
る。切替回路８には第２のフイルタ６の出力（位
相反転しない信号）も送られている。第２のフイ
ルタ６の出力信号と位相反転回路７の出力信号
は、切替回路８によつて第１のフイルタ４の出力
信号の極性反転ごとに交互に切替えられて平衡結
線網２に送られる。切替回路８の出力は、例え
ば、第２図に示すような波形であり、第２のフイ
ルタ６の出力電流を全波整流したような波形とな
つている。しかし、その極性は、平衡結線網２の
インピダンスと線路インピダンスの大小関係に対
応して異なつている。すなわち、切替回路８の出
力電流は、大きさが平衡結線網２と線路とのイン
ピダンス不平衡量に対応し、極性が平衡結線網の
インピダンスが高低いずれにずれているかに対応
している。この結果、平衡結線網２に電流依存性
可変抵抗を用いることにより、刻々と変動する線
路インピダンスに対して該結線網２のインピダン
スを制御することにより平衡をとることができ
る。ここで極性変化について詳細に説明する。ハ
イブリツドコイルの略図及び等価回路はそれぞれ
第３図および第４図に示す構成となつている。第
４図において
(イ) ＺA＝ＺCならばI2＝I3のため、ＺBに発生する
電圧は次のように表わされる。 The 50Hz modulated wave is extracted by the first filter 4. On the other hand, due to the unbalance between the impedance of the balanced wiring network 2 and the line impedance, a part of the frequency shift signal goes around to the receiving terminal R side. This wraparound current is input to the second modulator 5 and modulated by the modulation current (202.35kHz) input from the terminal M, and becomes a modulated current including 50Hz, which is then input to the second filter 6. through 50Hz
It is said that only The output current of the second filter 6 is sent to the switching circuit 8 via the phase inversion circuit 7. The output of the second filter 6 (a signal whose phase is not inverted) is also sent to the switching circuit 8. The output signal of the second filter 6 and the output signal of the phase inversion circuit 7 are alternately switched by the switching circuit 8 every time the polarity of the output signal of the first filter 4 is reversed and sent to the balanced connection network 2. The output of the switching circuit 8 has a waveform as shown in FIG. 2, for example, and is a waveform obtained by full-wave rectification of the output current of the second filter 6. However, the polarity differs depending on the magnitude relationship between the impedance of the balanced wiring network 2 and the line impedance. That is, the output current of the switching circuit 8 has a magnitude corresponding to the amount of impedance unbalance between the balanced wiring network 2 and the line, and a polarity corresponding to whether the impedance of the balanced wiring network is higher or lower. As a result, by using a current-dependent variable resistor in the balanced wiring network 2, it is possible to balance the constantly changing line impedance by controlling the impedance of the wiring network 2. Here, polarity change will be explained in detail. A schematic diagram and an equivalent circuit of the hybrid coil are shown in FIGS. 3 and 4, respectively. In FIG. 4, (a) If Z A = Z C , then I 2 = I 3 , so the voltage generated at Z B is expressed as follows.
ＶB＝ＺB・（I2−I3）＝０
(ロ) 一方、ＺA＞ＺCならばI2＜I3となるから、ＺB
に発生する電圧は
ＶB＝ＺB・（I2−I3）＝負
(ハ) また、ＺA＜ＺCならばI2＞I3となり、
ＺBに発生する電圧は
ＶB＝ＺB・（I2−I3）＝正
このように、ＺBの電圧の極性はＺAとＺCの大
小関係に応じて変化する。上記３つのケースにお
ける各電圧波形およびそのときの切替回路の出力
は第５図に示される。 V B = Z B・(I 2 − I 3 )=0 (b) On the other hand, if Z A > Z C , I 2 < I 3 , so Z B
The voltage generated at Z B is V B = Z B · (I 2 − I 3 ) = negative (c) Also, if Z A < Z C , I 2 > I 3 , and the voltage generated at Z B is V B = Z B・(I 2 − I 3 )=Positive In this way, the polarity of the voltage at Z B changes depending on the magnitude relationship between Z A and Z C. Each voltage waveform in the above three cases and the output of the switching circuit at that time are shown in FIG.
すなわち、ＺA＞ＺCのときは、切替回路出力は
ＺAを小さくするよう正の電流を供給し、ＺA＜Ｚ
Cのときは、Zaを大きくするよう負の電流を供給
することにより、ＺA，ＺCを平衡させる。 That is, when Z A > Z C , the switching circuit output supplies a positive current to reduce Z A , and when Z A < Z
When C , Z A and Z C are balanced by supplying a negative current to increase Za.
次に、本実施例の動作について説明する。先
ず、通話電流等および周波数偏移信号は、ハイブ
リツドコイル１を介して４線−２線変換されて相
手局と授受される。前記変調器３および５は高イ
ンピダンスであるので、これらの信号授受には何
ら影響を与えない。端子Ｓから送信される周波数
偏移信号の一部は、第１の変調器３によつて変調
され、第１のフイルタ４を介して50Hzの被変調電
流のみが出力される。 Next, the operation of this embodiment will be explained. First, the communication current, etc. and the frequency shift signal are converted from 4-wire to 2-wire via the hybrid coil 1, and then transmitted to and received from the other station. Since the modulators 3 and 5 have high impedance, they have no effect on signal exchange. A part of the frequency shift signal transmitted from the terminal S is modulated by the first modulator 3, and only a modulated current of 50 Hz is outputted via the first filter 4.
一方、前記送信周波数偏移信号は、平衡結線網
２のインピダンス線路インピダンスの不平衡に基
づいて受信側に廻り込み、第２の変調器５によつ
て変調され、第２のフイルタ６を介して50Hzのみ
の出力とされる。切替回路８で上記フイルタ６の
出力と位相反転回路７の出力とは、第１のフイル
タの出力信号に同期して交互に切替えられて平衡
結線網２の可変抵抗へ送られる。該可変抵抗は、
切替回路８の出力電流の大きさと極性に応答して
抵抗値が制御され線路インピダンスとの平衡がと
られる。以上の動作によつて、送信側から受信側
への廻り込み電流を最小に抑圧することができ
る。また、上述の動作は、周波数偏移信号が該当
チヤネルの信号線のオン・オフに対応して高低い
ずれの周波数が送出されている場合であつても同
様に行なうことができる。廻り込み電流が抑圧さ
れると、受信側への妨害電流が減少するから線路
波器の帯域外減衰量は軽減することができる。
また、刻々と変化する線路インピダンスに追従し
て平衡をとることが可能であり、平衡結線網の調
整に手数と時間を要しないという効果もある。な
お、そのためにパイロツト信号を用いることは不
要であり、パイロツト信号抽出のための高価なフ
イルタ等を必要としない。 On the other hand, the transmission frequency shift signal goes around to the receiving side based on the unbalance of the impedance line impedance of the balanced connection network 2, is modulated by the second modulator 5, and is passed through the second filter 6. It is said that the output is only 50Hz. In the switching circuit 8, the output of the filter 6 and the output of the phase inversion circuit 7 are alternately switched in synchronization with the output signal of the first filter and sent to the variable resistor of the balanced wiring network 2. The variable resistance is
The resistance value is controlled in response to the magnitude and polarity of the output current of the switching circuit 8, and is balanced with the line impedance. By the above-described operation, it is possible to suppress the sneak current from the transmitting side to the receiving side to a minimum. Further, the above-mentioned operation can be performed in the same way even if the frequency shift signal is transmitted at either a high or a low frequency depending on whether the signal line of the corresponding channel is turned on or off. When the sneak current is suppressed, the interference current to the receiving side is reduced, so the out-of-band attenuation of the line waveform device can be reduced.
In addition, it is possible to balance the line impedance that changes from moment to moment, and there is also the effect that it does not require much effort and time to adjust the balanced connection network. Note that it is not necessary to use a pilot signal for this purpose, and an expensive filter or the like for extracting the pilot signal is not required.
本実施例で用いた位相反転回路７と切替回路８
に代えて、変調器を用い第２のフイルタ６の出力
信号を第１のフイルタ４の出力信号によつて変調
して平衡結線網２の可変抵抗を制御する電流を作
成してもよい。 Phase inversion circuit 7 and switching circuit 8 used in this example
Alternatively, a modulator may be used to modulate the output signal of the second filter 6 with the output signal of the first filter 4 to create a current that controls the variable resistance of the balanced wiring network 2.
さらに、平衡結線網２に電圧制御可変容量のコ
ンデンサを設けて、上述と同様の構成によつてイ
ンピダンスの虚数部も制御させさらに細かく平衡
をとることも可能である。 Furthermore, it is also possible to provide a capacitor with a voltage-controlled variable capacitance in the balanced wiring network 2, and to control the imaginary part of the impedance with the same configuration as described above, thereby achieving more fine balance.
以上のように、本発明においては、受信側にま
わり込んだ周波数偏移信号の大きさと位相に応じ
た制御電流を発生させて平衡結線網のインピダン
スを制御するように構成されているから、線路イ
ンピダンスが刻々と変化しても追従して平衡をと
ることができ、しかも、そのためにパイロツト信
号を必要としない。また、平衡結線網の調整に手
数と時間を必要としないという効果がある。 As described above, the present invention is configured to control the impedance of the balanced wiring network by generating a control current according to the magnitude and phase of the frequency shift signal that has passed around to the receiving side. Even if the impedance changes moment by moment, it can be followed and balanced, and no pilot signal is required for this purpose. Further, there is an effect that no effort and time are required for adjusting the balanced wiring network.
第１図は本発明の一実施例を示すブロツク図お
よび第２図は第１図の切替回路の出力信号の波形
図である。第３図〜第５図は極性変化を説明する
図である。
図において、１……ハイブリツドコイル、２…
…平衡結線網、３……第１の変調器、４……第１
のフイルタ、５……第２の変調器、６……第２の
フイルタ、７……位相反転回路、８……切替回
路、Ｓ，Ｒ，Ｌ，Ｍ……端子。
FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a waveform diagram of an output signal of the switching circuit shown in FIG. FIGS. 3 to 5 are diagrams for explaining polarity changes. In the figure, 1...hybrid coil, 2...
...Balanced connection network, 3...First modulator, 4...First
5... Second modulator, 6... Second filter, 7... Phase inversion circuit, 8... Switching circuit, S, R, L, M... terminals.
Claims (1)
に接続された第１の変調器と、この第１の変調器
の出力に接続された第１のフイルタと、前記ハイ
ブリツドコイルの前記４線側受信端子に並列に接
続された第２の変調器と、前記第２の変調器の出
力に接続された第２のフイルタと、この第２のフ
イルタの出力信号の位相を反転する位相反転回路
と、前記第１のフイルタの出力信号の極性反転に
応答して前記第２のフイルタの出力信号と前記位
相反転回路の出力信号とを交互に切替え出力する
切替回路と、該切替回路の出力信号の大きさと極
性とによつて制御される可変抵抗を含む平衡結線
網とを備え、前記送信端子から前記ハイブリツド
コイルの２線線路側に送出される周波数偏移信号
の一部を前記第１の変調器を介して基準周波数信
号によつて変調し、前記第１のフイルタによつて
被変調波を分離抽出し、前記受信端子側に廻り込
んだ前記周波数偏移信号を前記第２の変調器を介
して前記基準周波数信号によつて変調し、前記第
２のフイルタの出力と前記反転回路の出力とを前
記切替回路を介して前記第１のフイルタの出力の
極性が反転されるたびに交互に切替え前記可変抵
抗に送り、前記可変抵抗の抵抗値を制御するよう
にしたことを特徴とするハイブリツド回路。1 A first modulator connected in parallel to the 4-wire side transmitting terminal of the hybrid coil, a first filter connected to the output of the first modulator, and the 4-wire side receiving terminal of the hybrid coil. a second modulator connected in parallel to the second modulator; a second filter connected to the output of the second modulator; a phase inversion circuit for inverting the phase of the output signal of the second filter; a switching circuit that alternately switches and outputs the output signal of the second filter and the output signal of the phase inversion circuit in response to polarity inversion of the output signal of the first filter; and a magnitude of the output signal of the switching circuit; a balanced wiring network including a variable resistance controlled by the polarity of the hybrid coil; The modulated wave is modulated by the reference frequency signal through the first filter, the modulated wave is separated and extracted, and the frequency-shifted signal that has passed around to the receiving terminal is modulated by the second modulator. modulated by the reference frequency signal, and alternately switches the output of the second filter and the output of the inversion circuit via the switching circuit each time the polarity of the output of the first filter is inverted; 1. A hybrid circuit, characterized in that the signal is sent to a variable resistor to control the resistance value of the variable resistor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8436980A JPS5710537A (en) | 1980-06-20 | 1980-06-20 | Hybrid circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8436980A JPS5710537A (en) | 1980-06-20 | 1980-06-20 | Hybrid circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5710537A JPS5710537A (en) | 1982-01-20 |
| JPS6134701B2 true JPS6134701B2 (en) | 1986-08-08 |
Family
ID=13828607
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8436980A Granted JPS5710537A (en) | 1980-06-20 | 1980-06-20 | Hybrid circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5710537A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6161805U (en) * | 1984-09-27 | 1986-04-25 |
-
1980
- 1980-06-20 JP JP8436980A patent/JPS5710537A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6161805U (en) * | 1984-09-27 | 1986-04-25 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5710537A (en) | 1982-01-20 |
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