JPH07307621A - Delay line type frequency demodulator - Google Patents
Delay line type frequency demodulatorInfo
- Publication number
- JPH07307621A JPH07307621A JP12072394A JP12072394A JPH07307621A JP H07307621 A JPH07307621 A JP H07307621A JP 12072394 A JP12072394 A JP 12072394A JP 12072394 A JP12072394 A JP 12072394A JP H07307621 A JPH07307621 A JP H07307621A
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- Prior art keywords
- delay line
- signal
- output
- phase shifter
- line type
- Prior art date
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、遅延線方式ＦＭ復調器
に係り、特に復調動作点の自動調整方式の改良に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a delay line type FM demodulator, and more particularly to improvement of an automatic adjustment system of a demodulation operating point.
【０００２】[0002]
【従来の技術】遅延線方式ＦＭ復調器は、例えば図３に
示すように、リミッタ１と乗算器２と電圧制御移相器３
ｂとローパスフィルタ４と積分器５とを基本的に備え、
図４に示す如くに動作して復調動作点の自動調整を行
う。2. Description of the Related Art A delay line type FM demodulator has a limiter 1, a multiplier 2 and a voltage controlled phase shifter 3 as shown in FIG.
b, a low-pass filter 4 and an integrator 5 are basically provided,
It operates as shown in FIG. 4 to automatically adjust the demodulation operating point.
【０００３】図３において、リミッタ１にて振幅制限を
受けたＦＭ信号は、２分岐され、一方の分岐信号が基準
信号として乗算器２の一方の入力となり、他方の分岐信
号が電圧制御移相器３ｂにて積分器５の出力（制御信
号）に従って移相制御されて遅延信号となり乗算器２の
他方の入力となる。In FIG. 3, the FM signal whose amplitude is limited by the limiter 1 is branched into two, one branch signal serving as a reference signal to be one input of the multiplier 2, and the other branch signal being a voltage control phase shift. The phase shift control is performed by the device 3b in accordance with the output (control signal) of the integrator 5 to form a delay signal, which is the other input of the multiplier 2.
【０００４】乗算器２は、基準信号と遅延信号とを乗算
してＦＭ復調を行う。乗算器２としては、いわゆる乗算
器の他に、排他的論理和ゲート、ＡＮＤゲート、フリッ
プフロップ等、出力信号のデューティ比が２つの入力信
号間の相対的位相に従って変化するものであれば、同様
に使用できる。The multiplier 2 multiplies the reference signal and the delayed signal to perform FM demodulation. The multiplier 2 is not limited to a so-called multiplier, but may be an exclusive OR gate, an AND gate, a flip-flop, or the like as long as the duty ratio of the output signal changes according to the relative phase between two input signals. Can be used for
【０００５】この乗算器２の出力はローパスフィルタ４
にてろ波処理され信号周波数成分が復調出力として外部
へ送出されるが、その一部が積分器５を介して電圧制御
移相器３ｂに与えられ、図４に示す如くして復調動作点
の自動調整が行われる。The output of the multiplier 2 is the low-pass filter 4
The signal frequency component subjected to the filtering process is sent to the outside as a demodulation output, but a part of the signal frequency component is given to the voltage control phase shifter 3b via the integrator 5, and as shown in FIG. Automatic adjustment is performed.
【０００６】図４において、ＦＭ復調の最適動作点は、
図４（Ａ）の（ａ）に示すように、基準信号と遅延信号
との位相差Δθが（２ｎ＋１）π／２の時であり、その
時の乗算器２の出力はゼロ電圧を中心に上下等振幅、つ
まり最大振幅であり、積分器５で抽出される直流成分は
ゼロである（図４（Ｂ）の（ａ））。In FIG. 4, the optimum operating point of FM demodulation is
As shown in (a) of FIG. 4 (A), when the phase difference Δθ between the reference signal and the delayed signal is (2n + 1) π / 2, the output of the multiplier 2 at that time rises and falls around the zero voltage. The amplitude is equal, that is, the maximum amplitude, and the DC component extracted by the integrator 5 is zero ((a) in FIG. 4B).
【０００７】そして、温度変動や周波数変動によって動
作点がずれると、乗算器２の出力は図４（Ａ）の（ｂ）
（ｃ）に示すように片側の振幅が歪み、振幅の中心を与
える直流成分が変化し、復調可能な出力レベルが小さく
なる。この動作点のずれに応じた直流成分が積分器５で
抽出される（図４（Ｂ）の（ｂ）（ｃ））。When the operating point shifts due to temperature fluctuations and frequency fluctuations, the output of the multiplier 2 is (b) in FIG. 4 (A).
As shown in (c), the amplitude on one side is distorted, the DC component that gives the center of the amplitude changes, and the output level that can be demodulated decreases. A direct current component corresponding to the shift of the operating point is extracted by the integrator 5 ((b) and (c) in FIG. 4B).
【０００８】つまり、積分器５が抽出した直流成分を制
御信号として電圧制御移相器３ｂにフィードバックし、
電圧制御移相器３ｂにその直流成分をゼロにするように
リミッタ１の出力を移相制御させ、移相した遅延信号を
乗算器２に与えるループ制御により、最適動作点に自動
調整できるようにしている。That is, the DC component extracted by the integrator 5 is fed back to the voltage control phase shifter 3b as a control signal,
The voltage control phase shifter 3b controls the output of the limiter 1 to shift the DC component to zero, and the delay control signal is applied to the multiplier 2 by loop control so that the optimum operating point can be automatically adjusted. ing.
【０００９】ここに、従来の電圧制御移相器３ｂは、図
５に示すように、一定の遅延量を持つトランジスタから
なるゲート回路１２の多数個を縦列接続し、各出力を選
択回路１１が積分器５の出力（制御信号）に従って選択
し、それを乗算器２への遅延信号として出力するように
構成されている（例えば特開昭６１−３５０１６号公報
参照）。Here, in the conventional voltage controlled phase shifter 3b, as shown in FIG. 5, a large number of gate circuits 12 composed of transistors having a constant delay amount are connected in cascade, and each output is selected by a selection circuit 11. It is configured to select according to the output (control signal) of the integrator 5 and output it as a delayed signal to the multiplier 2 (see, for example, Japanese Patent Laid-Open No. 61-35016).
【００１０】[0010]
【発明が解決しようとする課題】従来の遅延線方式ＦＭ
復調器では、復調動作点の自動調整にトランジスタから
なるゲート回路を用いるので、移相量の調整ステップは
ナノ秒単位である。ところが、搬送周波数が数百ＭＨｚ
〜数ＧＨｚの場合には、１／１０ナノ秒単位の移相量調
整が必要となるので、従来の自動調整方式では対応でき
ず、新たな方式の開発が望まれている。DISCLOSURE OF THE INVENTION Conventional delay line type FM
Since the demodulator uses a gate circuit composed of transistors for automatic adjustment of the demodulation operating point, the step of adjusting the amount of phase shift is in nanosecond units. However, the carrier frequency is several hundred MHz
In the case of up to several GHz, it is necessary to adjust the amount of phase shift in units of 1/10 nanosecond. Therefore, the conventional automatic adjustment method cannot handle this, and the development of a new method is desired.
【００１１】本発明は、このような問題に鑑みなされた
もので、その目的は、搬送周波数が数百ＭＨｚ〜数ＧＨ
ｚと高い場合でも支障なく復調動作点の自動調整を行う
ことができる遅延線方式ＦＭ復調器を提供することにあ
る。The present invention has been made in view of the above problems, and an object thereof is to provide a carrier frequency of several hundred MHz to several GH.
An object of the present invention is to provide a delay line type FM demodulator capable of automatically adjusting the demodulation operating point even if z is high.
【００１２】[0012]
【課題を解決するための手段】前記目的を達成するため
に、本発明の遅延線方式ＦＭ復調器は次の如き構成を有
する。即ち、本発明の遅延線方式ＦＭ復調器は、ＦＭ信
号の振幅を制限するリミッタと； リミッタの出力信号
の移相量を制御信号に従って変化させる電圧制御移相器
と； リミッタの出力信号（基準信号）と電圧制御移相
器の出力信号（遅延信号）とを乗算しＦＭ復調を行う乗
算器と； 乗算器の出力信号から信号周波数成分を復調
出力として取り出すローパスフィルタと； 前記電圧制
御移相器に対する制御信号を復調出力から復調動作点の
ずれに応じて変化する直流成分を抽出して形成する積分
器と； を備える遅延線方式ＦＭ復調器において； 前
記電圧制御移相器は、リミッタの出力信号に固定移相量
を与える遅延線と； 遅延線出力の移相量を前記制御信
号に従って微調整し前記遅延信号を出力する移相器と；
を備えることを特徴とするものである。In order to achieve the above object, the delay line type FM demodulator of the present invention has the following configuration. That is, the delay line type FM demodulator of the present invention includes a limiter that limits the amplitude of the FM signal; a voltage control phase shifter that changes the phase shift amount of the output signal of the limiter according to the control signal; and an output signal of the limiter (reference). A signal) and an output signal (delayed signal) of the voltage control phase shifter for FM demodulation; a low-pass filter for extracting a signal frequency component from the output signal of the multiplier as a demodulation output; A delay line type FM demodulator which forms a control signal for the demodulator from a demodulation output by extracting a DC component that changes according to the deviation of the demodulation operating point, and the voltage control phase shifter is a limiter. A delay line for giving a fixed phase shift amount to the output signal; a phase shifter for finely adjusting the phase shift amount of the delay line output according to the control signal and outputting the delay signal;
It is characterized by including.
【００１３】なお、遅延線は同軸ケーブルを用いること
ができる。また移相器はアイソレータと電圧リアクタン
ス回路の組合わせで構成できる。電圧リアクタンス回路
は可変リアクタンス素子を備えるが、この可変リアクタ
ンス素子は、具体的にはバラクタ・ダイオードである。A coaxial cable can be used as the delay line. Further, the phase shifter can be constructed by combining an isolator and a voltage reactance circuit. The voltage reactance circuit includes a variable reactance element, and this variable reactance element is specifically a varactor diode.
【００１４】[0014]
【作用】次に、本発明の遅延線方式ＦＭ復調器の作用を
説明する。本発明では、遅延線により固定移相量を与
え、アイソレータと電圧制御リアクタンス回路により移
相量を微調整する。これらの要素は高周波に対応でき、
１／１０ナノ秒単位の移相量調整が可能である。Next, the operation of the delay line type FM demodulator of the present invention will be described. In the present invention, a fixed phase shift amount is given by the delay line, and the phase shift amount is finely adjusted by the isolator and the voltage control reactance circuit. These elements can handle high frequencies,
It is possible to adjust the amount of phase shift in units of 1/10 nanosecond.
【００１５】従って、搬送周波数が数百ＭＨｚ〜数ＧＨ
ｚと高い場合でも任意のＦＭ復調特性において温度変動
や周波数変動に関係なく、最大限の振幅が得られる。な
お、遅延線は固定移相量を与えるものであり、アイソレ
ータと電圧リアクタンス回路の組合わせからなる移相器
も調整部分がないので、復調動作点の調整工数は不要で
あるという利点もある。Therefore, the carrier frequency is several hundred MHz to several GH.
Even if z is high, the maximum amplitude can be obtained in any FM demodulation characteristic regardless of temperature fluctuation and frequency fluctuation. The delay line provides a fixed amount of phase shift, and since the phase shifter including the combination of the isolator and the voltage reactance circuit does not have an adjusting portion, there is also an advantage that the man-hour for adjusting the demodulation operating point is unnecessary.
【００１６】[0016]
【実施例】以下、本発明の実施例を図面を参照して説明
する。図１は、本発明の一実施例に係る遅延線方式ＦＭ
復調器を示す。本発明では、電圧制御移相器３ａの構成
が従来のもの（図５）と異なる。その他は図３と同様で
あり、同一符号名称を付してある。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a delay line type FM according to an embodiment of the present invention.
A demodulator is shown. In the present invention, the configuration of the voltage controlled phase shifter 3a is different from the conventional one (FIG. 5). Others are the same as those in FIG. 3, and the same reference numerals are given.
【００１７】図１において、本発明の電圧制御移相器３
ａは、遅延線６とアイソレータ７と電圧制御リアクタン
ス回路８とで基本的に構成される。Referring to FIG. 1, the voltage controlled phase shifter 3 of the present invention.
Basically, a is composed of the delay line 6, the isolator 7, and the voltage control reactance circuit 8.
【００１８】遅延線６は、例えば適宜長さの同軸ケーブ
ルであり、リミッタ１の出力に対し固定値の移相量を与
える。The delay line 6 is, for example, a coaxial cable of an appropriate length and gives a fixed amount of phase shift to the output of the limiter 1.
【００１９】そして、アイソレータ７と電圧制御リアク
タンス回路８の組合わせによる移相器により遅延線出力
の移相量を積分器５が出力する制御信号に従って微調整
し、乗算器２の他方の入力端に遅延信号を出力する。Then, the phase shifter formed by combining the isolator 7 and the voltage control reactance circuit 8 finely adjusts the phase shift amount of the delay line output according to the control signal output from the integrator 5, and the other input end of the multiplier 2 The delayed signal is output to.
【００２０】この移相器は、具体的には図２（ａ）に示
すように、アイソレータ７と可変リアクタンス素子９と
を組合わせたもので、アイソレータ７への入力信号は可
変リアクタンス素子９に入り、そこで反射され再びアイ
ソレータ７に入り、その出力ポートから出力されるが、
入力信号（sin ωｔ）に対し、可変リアクタンス素子で
反射された出力信号は、sin(ωｔ＋Δθ）となり、位相
が遅れる性質を利用し、積分器５の出力（制御信号）で
リアクタンスを変化させれば遅延線出力の位相の微調整
ができる。Specifically, this phase shifter is a combination of an isolator 7 and a variable reactance element 9, as shown in FIG. 2A, and an input signal to the isolator 7 is fed to the variable reactance element 9. It enters, is reflected there, enters the isolator 7 again, and is output from its output port.
With respect to the input signal (sin ωt), the output signal reflected by the variable reactance element becomes sin (ωt + Δθ), and if the reactance is changed by the output (control signal) of the integrator 5 by utilizing the property that the phase is delayed. The phase of the delay line output can be finely adjusted.
【００２１】なお、図２（ｂ）に示すように可変リアク
タンス素子としてバラクタ・ダイオード１０が現時点で
は好適である。A varactor diode 10 is currently suitable as a variable reactance element as shown in FIG. 2 (b).
【００２２】このように、本発明の電圧制御移相器３ａ
は、高周波にも対応できる構成であり、図４に示した復
調動作点の自動調整を搬送周波数が数ＭＨｚ〜数ＧＨｚ
と高い場合において１／１０ナノ秒単位の移相量調整で
同様になし得ることは明らかである。As described above, the voltage controlled phase shifter 3a of the present invention is used.
Has a configuration capable of supporting high frequencies, and the automatic adjustment of the demodulation operating point shown in FIG. 4 is performed at carrier frequencies of several MHz to several GHz.
It is obvious that the same can be done by adjusting the amount of phase shift in units of 1/10 nanosecond in the high case.
【００２３】[0023]
【発明の効果】以上説明したように、本発明の遅延線方
式ＦＭ復調器では、電圧制御移相器を高周波に対応でき
る遅延線とアイソレータと電圧制御リアクタンス回路の
組合わせにより構成し、遅延信号の移相量を微調整でき
るようにしたので、搬送周波数が数百ＭＨｚ〜数ＧＨｚ
と高い場合でも任意のＦＭ復調特性において温度変動や
周波数変動に関係なく、最大限の振幅が得られる効果が
ある。なお、遅延線は固定移相量を与えるものであり、
アイソレータと電圧リアクタンス回路の組合わせからな
る移相器も調整部分がないので、復調動作点の調整工数
は不要であるという利点もある。As described above, in the delay line type FM demodulator of the present invention, the voltage control phase shifter is constituted by the combination of the delay line capable of supporting high frequency, the isolator and the voltage control reactance circuit, and the delay signal Since the phase shift amount of can be finely adjusted, the carrier frequency is several hundred MHz to several GHz.
Even if it is high, there is an effect that the maximum amplitude can be obtained irrespective of temperature fluctuation and frequency fluctuation in arbitrary FM demodulation characteristics. The delay line gives a fixed amount of phase shift,
Since the phase shifter, which is a combination of the isolator and the voltage reactance circuit, also has no adjustment part, there is also an advantage that the adjustment man-hours of the demodulation operating point are unnecessary.
【図１】本発明の一実施例に係る遅延線方式ＦＭ復調器
の構成ブロック図である。FIG. 1 is a configuration block diagram of a delay line type FM demodulator according to an embodiment of the present invention.
【図２】本発明の電圧制御移相器の移相器の説明図であ
り、（ａ）は移相器の構成及び動作の説明図、（ｂ）は
移相器の具体的構成例を示す図である。2A and 2B are explanatory diagrams of a phase shifter of the voltage controlled phase shifter of the present invention, FIG. 2A is an explanatory diagram of a configuration and operation of the phase shifter, and FIG. 2B is a specific configuration example of the phase shifter. FIG.
【図３】遅延線方式ＦＭ復調器の基本構成ブロック図で
ある。FIG. 3 is a basic configuration block diagram of a delay line type FM demodulator.
【図４】遅延線方式ＦＭ復調器が行う復調動作点の自動
調整動作の一般的な説明図であり、（Ａ）は乗算器の出
力特性図、（Ｂ）は積分器の出力特性図である。FIG. 4 is a general explanatory diagram of an automatic adjustment operation of a demodulation operating point performed by a delay line type FM demodulator, (A) is an output characteristic diagram of a multiplier, and (B) is an output characteristic diagram of an integrator. is there.
【図５】従来の電圧制御移相器の構成ブロック図であ
る。FIG. 5 is a configuration block diagram of a conventional voltage controlled phase shifter.
１ リミッタ ２ 乗算器 ３ａ 電圧制御移相器 ４ ローパスフィルタ ５ 積分器 ６ 遅延線 ７ アイソレータ ８ 電圧制御リアクタンス回路 ９ 可変リアクタンス素子 １０ バラクタ・ダイオード 1 Limiter 2 Multiplier 3a Voltage control phase shifter 4 Low pass filter 5 Integrator 6 Delay line 7 Isolator 8 Voltage control reactance circuit 9 Variable reactance element 10 Varactor diode
─────────────────────────────────────────────────────
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【手続補正書】[Procedure amendment]
【提出日】平成７年１月３１日[Submission date] January 31, 1995
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】特許請求の範囲[Name of item to be amended] Claims
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【特許請求の範囲】[Claims]
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】図面[Document name to be corrected] Drawing
【補正対象項目名】図２[Name of item to be corrected] Figure 2
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【図２】 [Fig. 2]
Claims (5)
リミッタの出力信号の移相量を制御信号に従って変化
させる電圧制御移相器と； リミッタの出力信号（基準
信号）と電圧制御移相器の出力信号（遅延信号）とを乗
算しＦＭ復調を行う乗算器と； 乗算器の出力信号から
信号周波数成分を復調出力として取り出すローパスフィ
ルタと； 前記電圧制御移相器に対する制御信号を復調
出力から復調動作点のずれに応じて変化する直流成分を
抽出して形成する積分器と；を備える遅延線方式ＦＭ復
調器において； 前記電圧制御移相器は、リミッタの出
力信号に固定移相量を与える遅延線と； 遅延線出力の
移相量を前記制御信号に従って微調整し前記遅延信号を
出力する移相器と； を備えることを特徴とする遅延線
方式ＦＭ復調器。1. A limiter for limiting the amplitude of an FM signal;
A voltage control phase shifter that changes the amount of phase shift of the output signal of the limiter according to the control signal; and an FM demodulation by multiplying the output signal (reference signal) of the limiter and the output signal (delay signal) of the voltage control phase shifter. A multiplier; a low-pass filter for extracting a signal frequency component from the output signal of the multiplier as a demodulation output; and a control signal for the voltage-controlled phase shifter, which extracts a DC component that changes according to the deviation of the demodulation operating point from the demodulation output. A delay line type FM demodulator comprising: an integrator formed by; a delay line that gives a fixed phase shift amount to an output signal of a limiter; and the phase shift amount of the delay line output is controlled by the delay line. A phase shifter which finely adjusts according to a signal and outputs the delayed signal, and a delay line type FM demodulator.
を特徴とする請求項１に記載の遅延線方式ＦＭ復調器。2. The delay line type FM demodulator according to claim 1, wherein the delay line is a coaxial cable.
ンス回路の組合わせで構成される； ことを特徴とする
請求項１に記載の遅延線方式ＦＭ復調器。3. The delay line type FM demodulator according to claim 1, wherein the phase shifter is composed of a combination of an isolator and a voltage reactance circuit.
ンス素子を備える；ことを特徴とする請求項２に記載の
遅延線方式ＦＭ復調器。4. The delay line type FM demodulator according to claim 2, wherein the voltage reactance circuit includes a variable reactance element.
イオードである；ことを特徴とする請求項４に記載の遅
延線方式ＦＭ復調器。5. The delay line type FM demodulator according to claim 4, wherein the variable reactance element is a varactor diode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12072394A JPH07307621A (en) | 1994-05-10 | 1994-05-10 | Delay line type frequency demodulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12072394A JPH07307621A (en) | 1994-05-10 | 1994-05-10 | Delay line type frequency demodulator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07307621A true JPH07307621A (en) | 1995-11-21 |
Family
ID=14793413
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12072394A Pending JPH07307621A (en) | 1994-05-10 | 1994-05-10 | Delay line type frequency demodulator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07307621A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102545887A (en) * | 2011-10-31 | 2012-07-04 | 中国电子科技集团公司第十三研究所 | Circuit with function of equivalent radiofrequency delay line |
| JP2017528261A (en) * | 2014-09-25 | 2017-09-28 | コーニンクレッカ フィリップス エヌ ヴェＫｏｎｉｎｋｌｉｊｋｅ Ｐｈｉｌｉｐｓ Ｎ．Ｖ． | Digital receive coil with built-in receive phase noise indicator |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60123131A (en) * | 1983-12-07 | 1985-07-01 | Iwatsu Electric Co Ltd | Signal delay device |
| JPH01125106A (en) * | 1987-11-10 | 1989-05-17 | Nec Corp | Fm demodulation circuit |
-
1994
- 1994-05-10 JP JP12072394A patent/JPH07307621A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60123131A (en) * | 1983-12-07 | 1985-07-01 | Iwatsu Electric Co Ltd | Signal delay device |
| JPH01125106A (en) * | 1987-11-10 | 1989-05-17 | Nec Corp | Fm demodulation circuit |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102545887A (en) * | 2011-10-31 | 2012-07-04 | 中国电子科技集团公司第十三研究所 | Circuit with function of equivalent radiofrequency delay line |
| JP2017528261A (en) * | 2014-09-25 | 2017-09-28 | コーニンクレッカ フィリップス エヌ ヴェＫｏｎｉｎｋｌｉｊｋｅ Ｐｈｉｌｉｐｓ Ｎ．Ｖ． | Digital receive coil with built-in receive phase noise indicator |
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