JPS638662B2 - - Google Patents
Info
- Publication number
- JPS638662B2 JPS638662B2 JP4150183A JP4150183A JPS638662B2 JP S638662 B2 JPS638662 B2 JP S638662B2 JP 4150183 A JP4150183 A JP 4150183A JP 4150183 A JP4150183 A JP 4150183A JP S638662 B2 JPS638662 B2 JP S638662B2
- Authority
- JP
- Japan
- Prior art keywords
- gain control
- automatic gain
- amplifier
- agc
- voltage
- 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
- 230000003321 amplification Effects 0.000 claims description 13
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 13
- 238000010586 diagram Methods 0.000 description 19
- 230000006866 deterioration Effects 0.000 description 5
- 239000003990 capacitor Substances 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G1/00—Details of arrangements for controlling amplification
- H03G1/0005—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal
- H03G1/0035—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal using continuously variable impedance elements
- H03G1/0052—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal using continuously variable impedance elements using diodes
- H03G1/0058—PIN-diodes
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G3/00—Gain control in amplifiers or frequency changers
- H03G3/20—Automatic control
Landscapes
- Radio Relay Systems (AREA)
- Control Of Amplification And Gain Control (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Description
【発明の詳細な説明】
本発明はヘテロダイン中継装置などに使用され
る自動利得制御増幅装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic gain control amplifier used in a heterodyne repeater or the like.
上記のような自動利得制御増幅装置は、あとに
図面を用いて説明するが、増幅器および自動利得
制御電圧（以下AGC電圧という）により制御さ
れる可変減衰器例えばピンダイオードを含む自動
利得制御増幅器（以下AGC増幅器という）を少
なくとも２段（ふつう４〜５段）接続した自動利
得制御増幅部（以下AGC増幅部という）と、出
力増幅部と、この出力増幅部の出力の電圧をレベ
ル検出器により検出し、検出した信号を自動利得
制御電圧発生器（以下AGC電圧発生器という）
で前記のAGC電圧に変えるようにしたものであ
る。 The automatic gain control amplifier as described above, which will be explained later with reference to the drawings, includes an amplifier and a variable attenuator controlled by an automatic gain control voltage (hereinafter referred to as AGC voltage), for example an automatic gain control amplifier ( An automatic gain control amplifier section (hereinafter referred to as an AGC amplifier section) in which at least two stages (usually 4 to 5 stages) of AGC amplifiers (hereinafter referred to as AGC amplifiers) are connected, an output amplifier section, and a level detector detects the voltage of the output of this output amplifier section. Detects and converts the detected signal into an automatic gain control voltage generator (hereinafter referred to as AGC voltage generator)
In this case, the AGC voltage is changed to the above-mentioned AGC voltage.
従来の自動利得制御増幅装置は、上記のような
構成において各AGC増幅器に同じAGC電圧を与
えて同じ減衰量の比率を得るようになつている。
しかしながらこの種の装置における歪特性は使用
した回路構成から求められる歪特性に比べてしば
しば大きくなることが経験されており、よつてそ
の原因を検討したところ、歪特性の劣化の原因の
最大のものは、これもあとから説明するが、可変
減衰器たとえばピンダイオードの減衰特性のバラ
ツキによるものであることを見出した。しかしそ
れであるからといつて特性の全く同じものを揃え
ることは実務的には容易でなく、また各段の可変
減衰器の特性をチエツクして段毎に補償するのは
コストの面で好ましくない。更にマイクロ波中継
機において低電力化を目指す場合電源電圧を可能
な限り低下させることが要求されるが、入力信号
が大きく最終段のAGC増幅器の動作レベルが大
きくなると低電源電圧では歪特性が問題となつて
くる。 In the conventional automatic gain control amplifier having the above configuration, the same AGC voltage is applied to each AGC amplifier to obtain the same attenuation ratio.
However, it has been experienced that the distortion characteristics in this type of equipment are often larger than the distortion characteristics required from the circuit configuration used, and when we investigated the causes, we found that the largest cause of deterioration in distortion characteristics was As will be explained later, they found that this is due to variations in the attenuation characteristics of variable attenuators, such as pin diodes. However, in practice, it is not easy to have identical attenuators with exactly the same characteristics, and it is undesirable from a cost perspective to check the characteristics of the variable attenuators in each stage and compensate each stage. . Furthermore, when aiming for low power consumption in microwave repeaters, it is necessary to lower the power supply voltage as much as possible, but when the input signal is large and the operating level of the final stage AGC amplifier becomes large, distortion characteristics become a problem at low power supply voltages. It's coming.
従つて、本発明の目的は歪特性の良好な自動利
得制御増幅装置、特に電源電圧が低くても歪特性
の小さい自動利得制御増幅装置を簡単な構成で得
ようとするものである。 SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an automatic gain control amplifier with good distortion characteristics, particularly an automatic gain control amplifier with low distortion characteristics even when the power supply voltage is low, with a simple configuration.
本発明は上記の目的を達成するために、前述の
ような構成の自動利得制御装置において、最終段
のAGC増幅器に与えるAGC電圧のレベルと最終
段以外の段のAGC増幅器に与えるAGC電圧のレ
ベルを互いに異ならせるようにしたものである。 In order to achieve the above object, the present invention provides an automatic gain control device configured as described above, in which the level of the AGC voltage applied to the final stage AGC amplifier and the level of the AGC voltage applied to the AGC amplifiers in stages other than the final stage are adjusted. are made to be different from each other.
すなわち本発明によれば、増幅器および自動利
得制御電圧により制御される可変減衰器から成る
自動利得制御増幅器を少なくとも２段含む自動利
得制御増幅部と、この自動利得制御増幅部の出力
を増幅する出力増幅部と、この出力増幅部の出力
レベルを検出して前記自動利得制御電圧を発生す
る自動利得制御電圧発生手段とを備えた増幅装置
において、前記自動利得制御電圧発生手段が、最
終段以外の段の自動利得制御増幅器の可変減衰量
の比率を上げてその動作レベルを下げると共に前
記最終段の自動利得制御増幅器の可変減衰量の比
率を下げてその利得を他段の自動利得制御増幅器
の利得より大きくするような自動利得制御電圧を
発生する手段であり、これにより規定のレベルの
歪特性の改善された信号が前記出力増幅部に入力
信号として与えられるようにしたことを特徴とす
る自動利得制御増幅装置が得られる。 That is, according to the present invention, there is provided an automatic gain control amplifier section including at least two stages of automatic gain control amplifiers each including an amplifier and a variable attenuator controlled by an automatic gain control voltage, and an output for amplifying the output of the automatic gain control amplifier section. In an amplifier device comprising an amplifier section and automatic gain control voltage generation means for detecting the output level of the output amplification section and generating the automatic gain control voltage, the automatic gain control voltage generation means The ratio of the variable attenuation of the automatic gain control amplifier in the final stage is increased to lower its operating level, and the ratio of the variable attenuation of the automatic gain control amplifier in the final stage is lowered to change its gain to the gain of the automatic gain control amplifier in the other stage. means for generating an automatic gain control voltage such that the gain is increased, whereby a signal with improved distortion characteristics at a specified level is given as an input signal to the output amplification section. A controlled amplifier is obtained.
次に図面を参照して詳細に説明する。 Next, a detailed explanation will be given with reference to the drawings.
第１図は従来の自動利得制御増幅装置の構成を
ブロツクで示した図であつて、１０は入力端子、
１１〜１４はAGC増幅器（全体をまとめてAGC
増幅部１４Ａとする）、１５は出力増幅部、１６
は出力端子、１７は検波器、１８はAGC電圧発
生器、３１〜３４はAGC電圧制御回路である。 FIG. 1 is a block diagram showing the configuration of a conventional automatic gain control amplifier, in which 10 is an input terminal;
11 to 14 are AGC amplifiers (the whole is AGC
15 is an output amplification section, 16 is an amplification section 14A);
17 is an output terminal, 17 is a detector, 18 is an AGC voltage generator, and 31 to 34 are AGC voltage control circuits.
第２図は上記のAGC増幅器１４（１１〜１３
も同じ）の構成をあらわした図で、１９は増幅
器、２０は高周波において印加電圧によりインピ
ーダンスの変わる可変減衰器（この場合ピンダイ
オード）、Ｃはコンデンサ、Ｌはコイルをあらわ
している。 Figure 2 shows the above AGC amplifier 14 (11 to 13).
19 is an amplifier, 20 is a variable attenuator (in this case a pin diode) whose impedance changes depending on the applied voltage at high frequencies, C is a capacitor, and L is a coil.
以下第１図および第２図を参照して従来装置の
動作を説明すると、入力端子１０から入力された
信号は１１〜１５の多段増幅器で増幅されて出力
端子１６に出力される。そして入力レベルの変動
に対して出力レベルを一定にするために、検波器
１７で出力レベルを検出し、AGC電圧発生器１
８は検出したレベル信号からAGC電圧を発生し、
これがAGC電圧制御回路３１〜３４を通りAGC
増幅部の各AGC増幅器１１〜１４に均等に供給
してその減衰量および利得の制御を行つている。 The operation of the conventional device will be described below with reference to FIGS. 1 and 2. A signal inputted from an input terminal 10 is amplified by multistage amplifiers 11 to 15 and outputted to an output terminal 16. In order to keep the output level constant against fluctuations in the input level, the output level is detected by the detector 17, and the AGC voltage generator 1
8 generates AGC voltage from the detected level signal,
This passes through the AGC voltage control circuits 31 to 34 and the AGC
The signal is evenly supplied to each of the AGC amplifiers 11 to 14 in the amplifier section to control the amount of attenuation and gain thereof.
第３図は第１図の自動利得制御増幅装置のレベ
ルダイヤグラムの例を示した図であつて、Ａは第
１図の装置で第２図に示すピンダイオード２０が
全く同じ減衰率を示し且つ増幅および減衰のレベ
ルが一定の場合を示した図、すなわち標準的な場
合のダイヤグラムを示したものである。しかし乍
ら実際には先に説明したようにピンダイオードの
減衰特性にバラツキがあり、例えば初段のAGC
増幅器１１の減衰量が同じAGC電圧では他の
AGC増幅器の減衰量に比較して小さいとすると、
第２図のダイヤグラムＢに示したような波形が得
られ、第２段以下計３段のAGC増幅器１２，１
３、および１４の入力レベルが高くなり、自動利
得制御装置としての歪特性を悪化させるという欠
点があつたのである。ここにE1は標準的な入力
レベル、E2は標準的な出力レベルの大きさをあ
らわしている。 FIG. 3 is a diagram showing an example of a level diagram of the automatic gain control amplifier shown in FIG. 1, in which A is the device shown in FIG. This is a diagram showing the case where the amplification and attenuation levels are constant, that is, the standard case. However, in reality, as explained earlier, there are variations in the attenuation characteristics of pin diodes.
At the same AGC voltage, the amount of attenuation of amplifier 11 is the same as that of other
Assuming that it is small compared to the attenuation of the AGC amplifier,
A waveform as shown in diagram B in Figure 2 is obtained, and a total of three stages of AGC amplifiers 12, 1 below the second stage are obtained.
This resulted in the disadvantage that the input levels of signals 3 and 14 became high, deteriorating the distortion characteristics of the automatic gain control device. Here, E 1 represents the standard input level, and E 2 represents the standard output level.
第４図は本発明の一実施例の構成をあらわした
図であり、１０〜１８及び３１〜３３の示す構成
要素は第１図の同じ参照数字の示す構成要素と同
じものであり、２１は電圧制御回路をあらわして
いる。 FIG. 4 is a diagram showing the configuration of an embodiment of the present invention, in which the components indicated by 10 to 18 and 31 to 33 are the same as the components indicated by the same reference numerals in FIG. It represents the voltage control circuit.
また第５図は第４図の装置の参照数字１３，１
４、および２１の示す構成要素を一部詳細に示し
た図であり、２２は増幅器、２３は可変減衰器
（ピンダイオード）、Ｒは抵抗器で電圧制御回路２
１を構成している。なおAGC増幅器１１〜１４
の可変減衰器はばらつきがあつて、AGC増幅部
１４Ａは第３図のＢに示すようなダイヤグラムを
示しているものとする。以下第４図および第５図
を併せ参照して装置の動作を説明する。入力端子
１０から入力された信号がAGC増幅器１１〜１
４および出力増幅部１５で増幅されて出力端子１
６に送出され、そしてこの出力のレベルが検波器
１７で検出され、AGC電圧発生器１８でAGC電
圧に変えられるまでは第１図の従来の場合と同じ
である。次にこのAGC電圧は始めの３段のAGC
増幅器１１〜１３にはAGC電圧制御回路３１〜
３３を通り供給されるが、第４段のAGC増幅器
１４には電圧制御回路２１を通してから供給され
る。そこで電圧制御回路２１よりも電圧制御回路
３１〜３３の制御量が大きいとするとAGC電圧
はAGC増幅器１１〜１３の可変減衰器の減衰を
大きくしてその動作レベルを第３図のダイヤグラ
ムＣの(1)，(2)，(3)に示すように低くし、適当な抵
抗値を持たせた電圧制御回路２１で低下した
AGC電圧はAGC増幅器１４の可変減衰器の減衰
を小さくしてその利得をダイヤグラムＣの(4)に示
すように大きくする。従つてAGC増幅器１１〜
１３の次段であるAGC増幅器１２〜１４はいず
れも歪特性の劣化を来すことなく動作することが
でき、而もAGC増幅部１４Ａの出力を第３図の
Ｆで示したレベルにすることができ、出力増幅部
１５への入力として供給することができる。従つ
て出力増幅部１５で増幅された装置出力は歪特性
の劣化はなく而も充分なレベルを有しており、装
置の正常な自動利得制御動作を可能とすることが
できる。 FIG. 5 also shows the reference numerals 13, 1 for the device in FIG.
4 and 21 in detail, 22 is an amplifier, 23 is a variable attenuator (pin diode), R is a resistor, and voltage control circuit 2
1. In addition, AGC amplifiers 11 to 14
It is assumed that the variable attenuator shown in FIG. The operation of the apparatus will be described below with reference to FIGS. 4 and 5. The signal input from input terminal 10 is sent to AGC amplifiers 11 to 1.
4 and the output amplification section 15 and output terminal 1.
6, and the level of this output is detected by a detector 17 and converted into an AGC voltage by an AGC voltage generator 18, which is the same as the conventional case shown in FIG. Next, this AGC voltage is applied to the first three stages of AGC.
AGC voltage control circuits 31 to 13 are connected to amplifiers 11 to 13.
33, but is supplied to the fourth stage AGC amplifier 14 after passing through the voltage control circuit 21. Therefore, assuming that the control amount of the voltage control circuits 31 to 33 is larger than that of the voltage control circuit 21, the AGC voltage increases the attenuation of the variable attenuators of the AGC amplifiers 11 to 13, and changes the operating level to ( As shown in 1), (2), and (3), the voltage was lowered by the voltage control circuit 21 with an appropriate resistance value.
The AGC voltage reduces the attenuation of the variable attenuator of the AGC amplifier 14 to increase its gain as shown in (4) of diagram C. Therefore, AGC amplifier 11~
All of the AGC amplifiers 12 to 14, which are the next stage to AGC amplifier 13, can operate without deterioration of distortion characteristics, and the output of AGC amplifier section 14A can be brought to the level shown by F in FIG. can be supplied as an input to the output amplification section 15. Therefore, the device output amplified by the output amplification section 15 has a sufficient level without deterioration of distortion characteristics, and can enable normal automatic gain control operation of the device.
なお上記の実施例ではすべてのAGC増幅器が
入力が標準の場合のE1又はそれ以下のレベルで
動作するようにしているが、それは絶対的のもの
ではなく、たとえばレベルダイヤグラムＣが(1)と
(2)の中間でE1より大きくても、それが大きくな
ければ全体としての歪特性の劣化は極めて僅かで
済み、従来の場合に比べれば歪特性は充分に改善
できる。すなわち、最終段のAGC増幅器１４の
AGC電圧の比率を変えるだけで歪特性を改善す
ることができる。また先の実施例では電圧制御回
路２１として抵抗器ＲをAGC電圧発生器１８の
出力に直列に用いたが、これを出力に並列に配置
して分圧方式をとつてもよく、また他の如何なる
形式のものでもよい。 Note that in the above embodiment, all AGC amplifiers operate at a level of E 1 or lower when the input is standard, but this is not absolute; for example, if the level diagram C is (1)
Even if E is larger than 1 in the middle of (2), as long as it is not large, the deterioration of the distortion characteristics as a whole is extremely slight, and the distortion characteristics can be sufficiently improved compared to the conventional case. In other words, the final stage AGC amplifier 14
Distortion characteristics can be improved simply by changing the AGC voltage ratio. Further, in the previous embodiment, the resistor R was used as the voltage control circuit 21 in series with the output of the AGC voltage generator 18, but it may also be placed in parallel with the output to provide a voltage division system, or other methods may be used. It can be of any format.
以上説明したように、本発明によれば、動作電
源電圧を低消費電力化の目的で下げても、AGC
増幅器の減衰量のバラツキによる歪特性の劣化
を、各段のAGC増幅器について補償することな
しに、最終段のAGC増幅器だけの電圧制御で
AGC増幅器全部の入力レベルを低くすることに
より防止するという利点がある。 As explained above, according to the present invention, even if the operating power supply voltage is lowered for the purpose of reducing power consumption, the AGC
Deterioration of distortion characteristics due to variations in amplifier attenuation can be avoided by voltage control of only the final stage AGC amplifier, without having to compensate for each stage AGC amplifier.
This has the advantage of being prevented by lowering the input level of all AGC amplifiers.
第１図は従来の自動利得制御増幅装置のブロツ
ク構成図、第２図は単一の自動利得制御増幅器
（AGC増幅器）の構成をあらわした図、３１〜３
３はAGC電圧制御回路、第３図は５段のAGC増
幅器内のレベルダイヤグラムをあらわす図、第４
図は本発明の一実施例の構成を示すブロツク図、
第５図は第４図におけるAGC増幅器と電圧制御
回路の構成をあらわした図である。
記号の説明：１０は入力端子、１１〜１４は各
段のAGC増幅器、１４ＡはAGC増幅部、１５は
出力増幅部、１６は出力端子、１７は検波器、１
８はAGC電圧発生器、２１は電圧制御回路、第
３図のＡは標準的なレベルダイヤグラム、Ｂはバ
ラツキによるレベルダイヤグラム、Ｃは改良後の
レベルダイヤグラム、E1は入力レベル、E2は出
力レベルをそれぞれあらわしている。
Figure 1 is a block diagram of a conventional automatic gain control amplifier, and Figure 2 is a diagram showing the configuration of a single automatic gain control amplifier (AGC amplifier).
3 is the AGC voltage control circuit, Figure 3 is a diagram showing the level diagram inside the 5-stage AGC amplifier, and Figure 4 is a diagram showing the level diagram inside the 5-stage AGC amplifier.
The figure is a block diagram showing the configuration of an embodiment of the present invention.
FIG. 5 is a diagram showing the configuration of the AGC amplifier and voltage control circuit in FIG. 4. Explanation of symbols: 10 is the input terminal, 11 to 14 are the AGC amplifiers of each stage, 14A is the AGC amplifier section, 15 is the output amplifier section, 16 is the output terminal, 17 is the detector, 1
8 is an AGC voltage generator, 21 is a voltage control circuit, A in Figure 3 is a standard level diagram, B is a level diagram due to variations, C is an improved level diagram, E 1 is an input level, and E 2 is an output. Each represents a level.
Claims (1)
れる可変減衰器から成る自動利得制御増幅器を少
なくとも２段含む自動利得制御増幅部と、この自
動利得制御増幅部の出力を増幅する出力増幅部
と、この出力増幅部の出力レベルを検出して前記
自動利得制御電圧を発生する自動利得制御電圧発
生手段とを備えた増幅装置において、前記自動利
得制御電圧発生手段が、最終段以外の段の自動利
得制御増幅器の可変減衰量の比率を上げてその動
作レベルを下げると共に前記最終段の自動利得制
御増幅器の可変減衰量の比率を下げてその利得を
他段の自動利得制御増幅器の利得より大きくする
ような自動利得制御電圧を発生する手段であり、
これにより規定のレベルの歪特性の改善された信
号が前記出力増幅部に入力信号として与えられる
ようにしたことを特徴とする自動利得制御増幅装
置。1. an automatic gain control amplification section including at least two stages of automatic gain control amplifiers each consisting of an amplifier and a variable attenuator controlled by an automatic gain control voltage; an output amplification section for amplifying the output of this automatic gain control amplification section; and automatic gain control voltage generation means for detecting the output level of an amplifier section and generating the automatic gain control voltage, wherein the automatic gain control voltage generation means is an automatic gain control amplifier in a stage other than the final stage. The automatic gain control amplifier increases the ratio of the variable attenuation of the automatic gain control amplifier in the final stage to lower its operating level, and lowers the ratio of the variable attenuation of the automatic gain control amplifier in the final stage to make its gain larger than the gain of the automatic gain control amplifier in the other stages. It is a means of generating a gain control voltage,
An automatic gain control amplification device characterized in that a signal with improved distortion characteristics at a prescribed level is thereby provided as an input signal to the output amplification section.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4150183A JPS59168728A (en) | 1983-03-15 | 1983-03-15 | Automatic gain control amplifier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4150183A JPS59168728A (en) | 1983-03-15 | 1983-03-15 | Automatic gain control amplifier |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59168728A JPS59168728A (en) | 1984-09-22 |
| JPS638662B2 true JPS638662B2 (en) | 1988-02-24 |
Family
ID=12610100
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4150183A Granted JPS59168728A (en) | 1983-03-15 | 1983-03-15 | Automatic gain control amplifier |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59168728A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3447282A1 (en) * | 1984-12-24 | 1986-07-10 | Telefunken electronic GmbH, 7100 Heilbronn | RADIO RECEIVER |
| FR2765750A1 (en) * | 1997-07-02 | 1999-01-08 | Trt Lucent Technologies | RECEIVING DEVICE FOR MICROWAVE SIGNALS |
-
1983
- 1983-03-15 JP JP4150183A patent/JPS59168728A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59168728A (en) | 1984-09-22 |
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