JPH04143670A - Distortion monitor circuit - Google Patents
Distortion monitor circuitInfo
- Publication number
- JPH04143670A JPH04143670A JP2266705A JP26670590A JPH04143670A JP H04143670 A JPH04143670 A JP H04143670A JP 2266705 A JP2266705 A JP 2266705A JP 26670590 A JP26670590 A JP 26670590A JP H04143670 A JPH04143670 A JP H04143670A
- Authority
- JP
- Japan
- Prior art keywords
- distortion
- frequency
- signal
- monitor circuit
- multiplexed signal
- 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
- 239000000284 extract Substances 0.000 claims description 6
- 238000001514 detection method Methods 0.000 abstract description 7
- 238000012544 monitoring process Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 5
- 230000003287 optical effect Effects 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 4
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
- G01R23/16—Spectrum analysis; Fourier analysis
- G01R23/20—Measurement of non-linear distortion
Landscapes
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Mathematical Physics (AREA)
- General Physics & Mathematics (AREA)
- Monitoring And Testing Of Transmission In General (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は周波数分割多重信号の歪みモニタ回路に関し、
特に非直線性によって生じる歪み雑音の発生状況をモニ
タする歪みモニタ回路に関する〔従来の技術〕
一般に、複数のチャネルからなる周波数分割多重信号を
扱う伝送システムにおいては、信号経路の非直線性によ
り歪み雑音が生じて信号の伝送品質が劣化する。従来、
端局を含む伝送路においてこのような歪み雑音の発生状
況を常時モニタ回路できる機能を有する伝送システムは
なかった。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a distortion monitor circuit for frequency division multiplexed signals;
[Prior art] Related to a distortion monitor circuit that monitors the occurrence of distortion noise caused especially by nonlinearity [Prior art] In general, in a transmission system that handles frequency division multiplexed signals consisting of multiple channels, distortion noise is generated due to nonlinearity of the signal path. occurs, degrading the signal transmission quality. Conventionally,
There has not been a transmission system that has a function of constantly monitoring the occurrence of such distortion noise in a transmission line including terminal stations.
本発明の目的は、非直線性による歪み雑音の発生状況を
常時モニタできる歪みモニタ回路を提供することにある
。An object of the present invention is to provide a distortion monitor circuit that can constantly monitor the occurrence of distortion noise due to nonlinearity.
本発明の歪みモニタ回路は、各チャネルの中心周波数の
間隔がｆｏ且つチャネルの最低中心周波数が２ｆｏ以上
の周波数分割多重信号における非直線性による歪み雑音
をモニタする歪みモニタ回路において、前記周波数分割
多重信号の占有帯域の最低周波数までの領域に発生する
所定の信号成分を取り出すフィルタと、このフィルタの
出力を所定のレベルに増幅する増幅器と、この増幅器の
出力を検波する第１の検波器と、前記周波数分割多重信
号を検波する第２の検波器と、前記第１および第２の検
波器の各出力の差を出力する差動増幅器とを備えて構成
されている。また、前記フィルタは、中心周波数ｆｏで
帯域幅ｆｏ以内の周波数成分を取り出す帯域フィルタで
構成してもよい。The distortion monitor circuit of the present invention monitors distortion noise due to nonlinearity in a frequency division multiplexed signal in which the center frequency interval of each channel is fo and the lowest center frequency of the channel is 2fo or more. a filter that extracts a predetermined signal component occurring in the region up to the lowest frequency of the occupied band of the signal; an amplifier that amplifies the output of this filter to a predetermined level; and a first detector that detects the output of this amplifier; It is configured to include a second detector that detects the frequency division multiplexed signal, and a differential amplifier that outputs the difference between the outputs of the first and second detectors. Further, the filter may be a bandpass filter that extracts frequency components within a bandwidth fo at a center frequency fo.
一般に、複数の信号からなる周波数分割多重信号には、
信号経路の非直線性によって歪み雑音が生じる。この場
合、任意の２つの信号の２次歪み、すなわち、２つの信
号の和差ビート成分は他の歪み成分に比してレベルが大
きい。いま、各チャネルの中心周波数の間隔をｆｏとし
、チャネルの最低中心周波数ｆ１を２ｆｏとすると、第
３図に示すように非直線性によって、周波数ｆｏを中心
に和差ビート成分が発生する。この和差ビート成分をモ
ニタ回路することにより、非直線性による歪み雑音の発
生状況を推測することができる。Generally, a frequency division multiplexed signal consisting of multiple signals is
Nonlinearities in the signal path create distortion noise. In this case, the second-order distortion of any two signals, that is, the sum-difference beat component of the two signals, has a higher level than other distortion components. Now, if the interval between the center frequencies of each channel is fo and the lowest center frequency f1 of the channel is 2fo, a sum-difference beat component is generated around the frequency fo due to non-linearity as shown in FIG. By monitoring this sum-difference beat component, it is possible to estimate the occurrence of distortion noise due to nonlinearity.
第１図は本発明の一実施例を示すブロック図であり、中
心周波数ｆＯで帯域幅ｆｏ以内の周波数成分を取り出す
帯域フィルタ１１と、帯域フィルタ１１の出力を増幅す
る増幅器１２と、検波器１３および１４と、差動増幅器
１５とを備えている。帯域フィルタ１１は、中心周波数
ｆｏで所定の帯域幅の周波数成分を取出す。増幅器１２
は、帯域フィルタエ１によって減衰して取出された所定
の周波数成分を減衰前のレベルになるように増幅する。FIG. 1 is a block diagram showing an embodiment of the present invention, which includes a bandpass filter 11 that extracts frequency components within a bandwidth fo at a center frequency fO, an amplifier 12 that amplifies the output of the bandpass filter 11, and a detector 13. and 14, and a differential amplifier 15. The bandpass filter 11 extracts frequency components of a predetermined bandwidth at the center frequency fo. Amplifier 12
, amplifies the predetermined frequency component that has been attenuated and extracted by the bandpass filter 1 to the level before attenuation.
検波器１３は所定の周波数成分を検波する。さて、周波
数分割多重信号Ｓ１を帯域フィルタ１１に入力して所定
の周波数成分のみを通過させ、増幅器１２により増幅し
た後、検波器１３によって検波して所定の周波数成分の
検波出力Ｌｌを得る。この検波出力Ｌｌが歪み雑音のレ
ベルをを示している。また、周波数分割多重信号Ｓｌを
を検波器１４で検波して周波数分割多重信号ＳＩの検出
力Ｌ２を得る。この検波出力Ｌ１およびＬ２を差動増幅
器１５に入力することにより、波数分割多重信号Ｓ１の
チャネル数に依存しない歪み雑音の相対値を得ることが
できる。この相対値を歪みモニタ出力Ｓｌとすることに
より、非直線性による歪み雑音の発生状況をモニタでき
る。The detector 13 detects a predetermined frequency component. Now, the frequency division multiplexed signal S1 is input to the bandpass filter 11 to pass only a predetermined frequency component, amplified by the amplifier 12, and then detected by the detector 13 to obtain a detection output Ll of the predetermined frequency component. This detection output Ll indicates the level of distortion noise. Further, the frequency division multiplexed signal SI is detected by the detector 14 to obtain the detection power L2 of the frequency division multiplexed signal SI. By inputting the detection outputs L1 and L2 to the differential amplifier 15, it is possible to obtain a relative value of distortion noise that does not depend on the number of channels of the wave number division multiplexed signal S1. By using this relative value as the distortion monitor output Sl, it is possible to monitor the occurrence of distortion noise due to nonlinearity.
第２図は第１図に示した歪みモニタ回路を光送信装置に
応用した一実施例を示すブロック図であり、周波数分割
多重信号８１に応じて光変調を行う発光素子２１におけ
る歪み雑音の発生状況をモニタする場合を示している。FIG. 2 is a block diagram showing an embodiment in which the distortion monitor circuit shown in FIG. This shows a case where the situation is monitored.
この場合、発光素子２１の出力光を受光素子２２で光−
電気変換し、更に、増幅器２３で所定のレベルに増幅し
た後、入力する周波数分割多重信号Ｓ１と共に歪みモニ
タ回路１０に供給して歪みモニタ出力ｓｌｌを得ている
。ここで、増幅器２４は発光素子２Ｉを周波数分割多重
信号Ｓ１に応じて駆動するための増幅器である。なお、
この歪みモニタ回路１０を光受信装置側にも設けること
により、光送信装置および光受信装置を含めた光伝送シ
ステムの非直線性による歪み雑音の発生状況をモニタす
ることができる。In this case, the light output from the light emitting element 21 is converted into light by the light receiving element 22.
After being electrically converted and further amplified to a predetermined level by an amplifier 23, it is supplied to the distortion monitor circuit 10 together with the input frequency division multiplexed signal S1 to obtain a distortion monitor output sll. Here, the amplifier 24 is an amplifier for driving the light emitting element 2I according to the frequency division multiplexed signal S1. In addition,
By providing this distortion monitor circuit 10 also on the optical receiving device side, it is possible to monitor the occurrence of distortion noise due to nonlinearity of the optical transmission system including the optical transmitting device and the optical receiving device.
以上説明したように本発明は、各チャネルの中心周波数
の間隔がｆｏ且つチャネルの最低中心周波数が２ｆｏ以
上の周波数分割多重信号において、伝送経路の非直線性
によって周波数多重信号の占有帯域の最低周波数までの
領域に発生する所定の信号成分をフィルタにより取り出
し、この所定の信号成分を増幅後横波した検波出力レベ
ルと周波数多重信号の検波出力レベルとの差をモニタす
ることにより、非直線性による歪み雑音の発生状況を常
時モニタできる。As explained above, in a frequency division multiplexed signal in which the center frequency interval of each channel is fo and the lowest center frequency of the channel is 2fo or more, the lowest frequency of the occupied band of the frequency division multiplexed signal is By using a filter to extract a predetermined signal component that occurs in the range up to The status of noise generation can be constantly monitored.
第１図は本発明の一実施例を示すブロック図、第２図は
第１図に示した歪みモニタ回路を光送信装置に応用した
一実施例を示すブロック図、第３図は周波数分割多重信
号を示す図である。
１０・・・・・・歪みモニタ回路、１１・・・・・・帯
域フィルタ、１２，２３，２４・・・・・・増幅器、１
３．１４・・・・・・検波器、１５・・・・・・差動増
幅器、２１・・・・・・発光素子、２２・・・・・・受
光素子、８１・・・・・・周波数分割多重信号、Ｓ腸・
・・・・・歪みモニタ出力。Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a block diagram showing an embodiment in which the distortion monitor circuit shown in Fig. 1 is applied to an optical transmitter, and Fig. 3 is a block diagram showing an embodiment of the invention. It is a figure which shows a signal. 10... Distortion monitor circuit, 11... Bandpass filter, 12, 23, 24... Amplifier, 1
3.14...Detector, 15...Differential amplifier, 21...Light emitting element, 22...Light receiving element, 81... Frequency division multiplexed signal, S.
...Distortion monitor output.
Claims (1)
ルの最低中心周波数が２ｆ＿０以上の周波数分割多重信
号における非直線性による歪み雑音をモニタする歪みモ
ニタ回路において、前記周波数分割多重信号の占有帯域
の最低周波数までの領域に発生する所定の信号成分を取
り出すフィルタと、このフィルタの出力を所定のレベル
に増幅する増幅器と、この増幅器の出力を検波する第１
の検波器と、前記周波数分割多重信号を検波する第２の
検波器と、前記第１および第２の検波器の各出力の差を
出力する差動増幅器とを備えたことを特徴とする歪みモ
ニタ回路。 ２、前記フィルタは、中心周波数ｆ＿０で帯域幅ｆ＿０
以内の周波数成分を取り出す帯域フィルタであることを
特徴とする請求項１記載の歪みモニタ回路[Claims] 1. In a distortion monitor circuit that monitors distortion noise due to nonlinearity in a frequency division multiplexed signal in which the center frequency interval of each channel is f_0 and the lowest center frequency of the channel is 2f_0 or more, a filter that extracts a predetermined signal component occurring in the region up to the lowest frequency of the occupied band of the signal, an amplifier that amplifies the output of this filter to a predetermined level, and a first detector that detects the output of this amplifier.
A distortion characterized by comprising: a wave detector, a second wave detector that detects the frequency division multiplexed signal, and a differential amplifier that outputs the difference between the respective outputs of the first and second wave detectors. monitor circuit. 2. The filter has a center frequency f_0 and a bandwidth f_0.
2. The distortion monitor circuit according to claim 1, wherein the distortion monitor circuit is a bandpass filter that extracts frequency components within
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2266705A JP2982272B2 (en) | 1990-10-04 | 1990-10-04 | Distortion monitor circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2266705A JP2982272B2 (en) | 1990-10-04 | 1990-10-04 | Distortion monitor circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04143670A true JPH04143670A (en) | 1992-05-18 |
| JP2982272B2 JP2982272B2 (en) | 1999-11-22 |
Family
ID=17434541
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2266705A Expired - Lifetime JP2982272B2 (en) | 1990-10-04 | 1990-10-04 | Distortion monitor circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2982272B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105093153A (en) * | 2015-08-18 | 2015-11-25 | 国网辽宁省电力有限公司大连供电公司 | Evaluation method for measurement nonlinearity of fundamental wave frequency reactive power |
-
1990
- 1990-10-04 JP JP2266705A patent/JP2982272B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105093153A (en) * | 2015-08-18 | 2015-11-25 | 国网辽宁省电力有限公司大连供电公司 | Evaluation method for measurement nonlinearity of fundamental wave frequency reactive power |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2982272B2 (en) | 1999-11-22 |
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