JPH0795545A - Distortion measuring method for catv system - Google Patents
Distortion measuring method for catv systemInfo
- Publication number
- JPH0795545A JPH0795545A JP23527293A JP23527293A JPH0795545A JP H0795545 A JPH0795545 A JP H0795545A JP 23527293 A JP23527293 A JP 23527293A JP 23527293 A JP23527293 A JP 23527293A JP H0795545 A JPH0795545 A JP H0795545A
- Authority
- JP
- Japan
- Prior art keywords
- head end
- distortion
- headend
- catv
- output
- 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.)
- Pending
Links
Landscapes
- Closed-Circuit Television Systems (AREA)
- Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はＣＡＴＶシステムの歪測
定方法に関し、特にＣＡＴＶシステムにおけるヘッドエ
ンドから出力される出力信号を加入者に伝送する伝送路
の歪率を出力信号の種別ごとに測定するＣＡＴＶシステ
ムの歪測定方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CATV system distortion measuring method, and more particularly to measuring the distortion factor of a transmission line for transmitting an output signal output from a head end in the CATV system to a subscriber for each type of output signal. The present invention relates to a CATV system distortion measuring method.
【０００２】[0002]
【従来の技術】従来のＣＡＴＶシステムの歪測定方法
は、ヘッドエンドから出力され中継器を通して伝送路上
を伝送された信号を中継器のモニタ端子から帯域通過フ
ィルタと補助増幅器とを介してスペクトルアナライザに
接続し、測定に必要なヘッドエンド内の信号送出器の出
力信号のオン／オフおよび出力レベルの可変をヘッドエ
ンド側で行ない、これをスペクトルアナライザで計測す
るという、計測員を２組用意する２パーティ構成で実行
していた。2. Description of the Related Art In a conventional CATV system distortion measuring method, a signal output from a head end and transmitted on a transmission path through a repeater is sent from a monitor terminal of the repeater to a spectrum analyzer through a bandpass filter and an auxiliary amplifier. Two sets of measurement personnel are prepared to connect, to turn on / off the output signal of the signal transmitter in the headend necessary for measurement, and to change the output level on the headend side, and to measure this with a spectrum analyzer. 2 It was running in a party configuration.
【０００３】[0003]
【発明が解決しようとする課題】この従来のＣＡＴＶ伝
送路の歪測定方法においては、ヘッドエンド側で計測対
象とする出力信号のオン／オフおよび出力レベルを可変
とする作業者と、伝送路中継器側の測定点で歪率を測定
する作業者が最低でも２人必要となるという問題点があ
った。SUMMARY OF THE INVENTION In this conventional CATV transmission line distortion measuring method, an operator who turns on / off an output signal to be measured on the head end side and an output level is variable, and a transmission line relay. There is a problem that at least two workers are required to measure the distortion at the measuring point on the instrument side.
【０００４】本発明の目的は上述した問題点を解決し、
伝送路の中継器側のみに作業者を配置して歪率を計測す
ることができるＣＡＴＶシステムの歪測定方法を提供す
ることにある。The object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide a distortion measuring method for a CATV system in which an operator can be arranged only on the repeater side of the transmission path to measure the distortion rate.
【０００５】[0005]
【課題を解決するための手段】本発明の歪測定方法は、
ＣＡＴＶシステムのヘッドエンドから出力される出力信
号を中継器を含んで加入者に伝送するＣＡＴＶ伝送路の
歪率を出力信号の種別ごとに測定するＣＡＴＶシステム
の歪測定方法において、前記ヘッドエンドの出力信号を
測定点からオン／オフ可能とするとともに前記ヘッドエ
ンドの出力信号レベルを歪率測定系で必要なゲイン直線
性を確保するように制御することを可能とした工程を有
する。The strain measuring method of the present invention comprises:
A CATV system distortion measuring method for measuring a distortion factor of a CATV transmission line for transmitting an output signal output from a head end of the CATV system to a subscriber including a repeater, in the distortion measuring method of the CATV system. There is a step of enabling the signal to be turned on / off from the measurement point and controlling the output signal level of the head end so as to secure the gain linearity required in the distortion measurement system.
【０００６】また本発明の歪率測定方法は、ＣＡＴＶシ
ステムのヘッドエンドから出力される出力信号を中継器
を含んで加入者に伝送するＣＡＴＶ伝送路の歪率を出力
信号の種別ごとに測定するＣＡＴＶシステムの歪測定方
法において、前記中継器のモニタ端子に方向性フィルタ
を接続し前記方向性フィルタの高域通過端子は帯域通過
フィルタと補助増幅器を介してスペクトルアナライザに
接続して前記ＣＡＴＶ伝送路の歪率測定に必要なスペク
トルを計測し、前記方向性フィルタの低域通過端子は前
記ヘッドエンドの遠隔制御用の制御信号を発生するヘッ
ドエンド操作盤に接続され、かつ前記制御信号は前記Ｃ
ＡＴＶ伝送路の上り回線を介して前記ヘッドエンド内蔵
のヘッドエンド制御盤に供給され、前記ヘッドエンド制
御盤によって前記ヘッドエンドの出力する測定対象の所
望の出力信号をオン／オフさせるとともに前記ＣＡＴＶ
伝送路の下り回線を介して送出する伝送信号を増幅する
増幅器の増幅度を可変とさせる構成を有する。Further, the distortion factor measuring method of the present invention measures the distortion factor of the CATV transmission line which transmits the output signal output from the head end of the CATV system to the subscriber including the repeater for each type of the output signal. In the distortion measurement method for a CATV system, a directional filter is connected to a monitor terminal of the repeater, and a high-pass terminal of the directional filter is connected to a spectrum analyzer via a bandpass filter and an auxiliary amplifier. Of the directional filter, the low pass terminal of the directional filter is connected to a headend operation panel for generating a control signal for remote control of the headend, and the control signal is the C signal.
The signal is supplied to the headend control board with the built-in headend via an upstream line of the ATV transmission line, and the headend control board turns on / off a desired output signal of the measurement target output from the headend and the CATV.
It has a configuration in which the amplification degree of an amplifier that amplifies a transmission signal transmitted via a downlink of a transmission line is variable.
【０００７】また本発明の歪測定方法は、前記ヘッドエ
ンドに入力した前記制御信号が、ヘッドエンド内蔵の方
向性フィルタの低域通過端子を介して出力され、かつ前
記方向性フィルタの高域通過端子は前記増幅器の出力に
接続した構成を有する。Further, in the distortion measuring method of the present invention, the control signal input to the head end is output via a low pass terminal of a directional filter built in the head end, and the high pass of the directional filter is passed. The terminal has a configuration connected to the output of the amplifier.
【０００８】[0008]
【実施例】次に、本発明について図面を参照して説明す
る。DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.
【０００９】図１は、本発明の一実施例の構成図であ
る。FIG. 1 is a block diagram of an embodiment of the present invention.
【００１０】本実施例は、ヘッドエンド１と、ＴＶ電波
を受信する複数のアンテナ、本実施例では２つのアンテ
ナ２およびアンテナ３と、自主放送設備４と、ＣＡＴＶ
中継増幅器５−１，…，５−（ｎ−１），５−ｎと、入
力信号を所定の高域及び低域に分離して出力する方向性
フィルタ６と、測定点からヘッドエンド１を遠隔制御す
るヘッドエンド操作盤７と、帯域通過フィルタ８と、補
助増幅器９およびスペクトルアナライザ１０を備える。In this embodiment, the head end 1, a plurality of antennas for receiving TV radio waves, two antennas 2 and 3 in this embodiment, an independent broadcasting facility 4, and a CATV.
The relay amplifiers 5-1, ..., 5- (n-1), 5-n, the directional filter 6 that separates the input signal into predetermined high and low frequencies and outputs the result, and the head end 1 from the measurement point A remote control headend operation panel 7, a bandpass filter 8, an auxiliary amplifier 9 and a spectrum analyzer 10 are provided.
【００１１】また、ヘッドエンド１は、アンテナ２及び
３で受信したＴＶ信号を処理するＴＶシグナルプロセッ
サ１１−１及び１１−２と、自主放送の信号を処理して
ＴＶ信号とするＴＶ変調器１２と、混合器２０と、増幅
器３０と、方向性フィルタ４０と、ＴＶシグナルプロセ
ッサ１１−１及び１１−２とＴＶ変調器１２との入力の
オン／オフを行なうとともに増幅器３０のゲイン調整を
行なうヘッドエンド制御盤５０のほか分岐器６０を備
え、図１にはなお、ＣＡＴＶ伝送路１００を併記して示
す。Further, the headend 1 has TV signal processors 11-1 and 11-2 for processing TV signals received by the antennas 2 and 3, and a TV modulator 12 for processing signals of independent broadcasting to obtain TV signals. A mixer, an amplifier 30, an directional filter 40, the input / output of the TV signal processors 11-1 and 11-2 and the TV modulator 12, and a gain adjustment of the amplifier 30. In addition to the end control board 50, a branching device 60 is provided, and the CATV transmission line 100 is also shown in FIG.
【００１２】次に、本実施例の動作について説明する。
測定点に配置したヘッドエンド操作盤７からヘッドエン
ド１の任意のチャンネルをオン／オフさせる制御信号７
０１を送出する制御信号７０１は、方向性フィルタ６に
よってＣＡＴＶ中継増幅器５−（ｎ−１）のモニタ端子
へと導かれ、他のＣＡＴＶ中継増幅器を含むＣＡＴＶ伝
送路１００のＣＡＴＶ上り回線でヘッドエンド１に送出
される。方向性フィルタ６は、入力を所定の低域と高域
とに分離し、制御信号７０１は低域通過信号としてＣＡ
ＴＶ中継増幅器５−（ｎ−１）に供給され、逆にＣＡＴ
Ｖ下り回線の伝送信号は高域通過信号として帯域通過フ
ィルタ８に供給される。Next, the operation of this embodiment will be described.
Control signal 7 for turning on / off any channel of the headend 1 from the headend operation panel 7 arranged at the measurement point
The control signal 701 for sending 01 is guided to the monitor terminal of the CATV relay amplifier 5- (n-1) by the directional filter 6, and is head-end in the CATV upstream line of the CATV transmission line 100 including other CATV relay amplifiers. Sent to 1. The directional filter 6 separates the input into a predetermined low band and high band, and the control signal 701 is a low-pass signal CA.
It is supplied to the TV relay amplifier 5- (n-1), and conversely CAT
The V downlink transmission signal is supplied to the band pass filter 8 as a high pass signal.
【００１３】ＣＡＴＶ上り回線で送出された制御信号７
０１は、ヘッドエンド１の方向性フィルタ４０によって
分岐器６０を介してヘッドエンド制御盤５０に供給され
る。制御信号７０１を入力したヘッドエンド制御盤５０
は、制御信号７０１によって指定されるヘッドエンド１
の任意のチャンネル、例えばＴＶプロセッサ１１−１を
含むチャンネルをオフとする。このオフ操作はＴＶシグ
ナルプロセッサ１１−１の入力を断とし、かつ所定の終
端抵抗で終端することによって行なわれる。次に、ヘッ
ドエンド操作盤７から送出する制御信号７０１の内容を
増幅器利得制御とし、オン／オフ制御の場合と同様にヘ
ッドエンド制御盤５０に供給する。ヘッドエンド制御盤
５０は、増幅器３０に供給しているゲイン設定用のバイ
アス電圧を変えることによって増幅器３０のゲイン調整
を行なう。このゲイン調整の内容は、歪率を計測する測
定系のゲインを調整し、測定系における入出力間の線形
増幅度を確保し計測の精度を保証するために行なわれ
る。Control signal 7 transmitted on the CATV uplink
01 is supplied to the headend control board 50 through the branching device 60 by the directional filter 40 of the headend 1. Headend control board 50 to which control signal 701 is input
Is the headend 1 designated by the control signal 701.
, Any channel including, for example, the TV processor 11-1 is turned off. This off operation is performed by disconnecting the input of the TV signal processor 11-1 and terminating with a predetermined terminating resistor. Next, the content of the control signal 701 sent from the headend operation panel 7 is subjected to amplifier gain control and is supplied to the headend control panel 50 as in the case of on / off control. The head-end control board 50 adjusts the gain of the amplifier 30 by changing the gain setting bias voltage supplied to the amplifier 30. The content of this gain adjustment is performed in order to adjust the gain of the measurement system for measuring the distortion rate, to secure the linear amplification degree between the input and output of the measurement system, and to guarantee the measurement accuracy.
【００１４】この状態において、測定したいＴＶシグナ
ルプロセッサ１１−１を含むチャンネルの歪成分すなわ
ち受信周波数以下の不要な周波数成分をＣＡＴＶ中継増
幅器５−（ｎ−１）のモニタ端子から帯域フィルタ８、
補助増幅器９を介してスペクトルアナライザ１０に入力
して歪率を求める。他のチャンネルの歪率についても同
様にして行なうことができる。In this state, the distortion component of the channel including the TV signal processor 11-1 to be measured, that is, the unnecessary frequency component below the reception frequency, is passed from the monitor terminal of the CATV relay amplifier 5- (n-1) to the band filter 8,
It is input to the spectrum analyzer 10 via the auxiliary amplifier 9 to obtain the distortion rate. The distortion factors of the other channels can be similarly measured.
【００１５】このようにして、測定点からの遠隔操作に
よって、作業者を大幅に圧縮したＣＡＴＶシステムの伝
送路の歪率を求めることができる。In this way, it is possible to obtain the distortion factor of the transmission line of the CATV system in which the operator is significantly compressed by remote control from the measuring point.
【００１６】なお、計測状態を原状態に復帰するには、
制御信号７０１によってチャンネルのオフ状態をオン状
態に戻し、かつ増幅器３０の利得を原状態に戻すことに
よって容易に行なうことができる。Incidentally, in order to return the measurement state to the original state,
This can be easily performed by returning the channel off state to the on state by the control signal 701 and returning the gain of the amplifier 30 to the original state.
【００１７】[0017]
【発明の効果】以上説明したように本発明は、ＣＡＴＶ
伝送路の歪率を測定する計測系の設定を測定点のみで可
能とすることにより、必要とする作業者を大幅に低減で
きる効果がある。As described above, the present invention is applicable to the CATV.
By enabling the setting of the measurement system for measuring the distortion of the transmission line only at the measurement points, there is an effect that the required number of workers can be significantly reduced.
【図１】本発明の一実施例の構成図である。FIG. 1 is a configuration diagram of an embodiment of the present invention.
１ ヘッドエンド ２，３ アンテナ ４ 自主放送設備 ５−１〜５−ｎ ＣＡＴＶ中継増幅器 ６ 方向性フィルタ ７ ヘッドエンド制御盤 ８ 帯域フィルタ ９ 補助増幅器 １０ スペクトルアナライザ １１−１，１１−２ ＴＶシグナルプロセッサ １２ ＴＶ変調器 ２０ 混合器 ３０ 増幅器 ４０ 方向性フィルタ ５０ ヘッドエンド制御盤 ６０ 分岐器 １００ ＣＡＴＶ伝送路 DESCRIPTION OF SYMBOLS 1 headend 2,3 antenna 4 independent broadcasting equipment 5-1 to 5-n CATV relay amplifier 6 directional filter 7 headend control panel 8 bandpass filter 9 auxiliary amplifier 10 spectrum analyzer 11-1, 11-2 TV signal processor 12 TV modulator 20 Mixer 30 Amplifier 40 Directional filter 50 Headend control panel 60 Brancher 100 CATV transmission line
Claims (3)
力される出力信号を中継器を含んで加入者に伝送するＣ
ＡＴＶ伝送路の歪率を出力信号の種別ごとに測定するＣ
ＡＴＶシステムの歪測定方法において、前記ヘッドエン
ドの出力信号を測定点からオン／オフ可能とするととも
に前記ヘッドエンドの出力信号レベルを歪率測定系で必
要なゲイン直線性を確保するように制御することを可能
としたことを特徴とするＣＡＴＶシステムの歪測定方
法。1. A C for transmitting an output signal output from a head end of a CATV system to a subscriber including a repeater.
C for measuring the distortion factor of the ATV transmission line for each type of output signal
In the distortion measurement method of an ATV system, the output signal of the head end can be turned on / off from a measurement point, and the output signal level of the head end is controlled so as to ensure gain linearity required in a distortion measurement system. A distortion measurement method for a CATV system, which enables the above.
力される出力信号を中継器を含んで加入者に伝送するＣ
ＡＴＶ伝送路の歪率を出力信号の種別ごとに測定するＣ
ＡＴＶシステムの歪測定方法において、前記中継器のモ
ニタ端子に方向性フィルタを接続し前記方向性フィルタ
の高域通過端子は帯域通過フィルタと補助増幅器を介し
てスペクトルアナライザに接続して前記ＣＡＴＶ伝送路
の歪率測定に必要なスペクトルを計測し、前記方向性フ
ィルタの低域通過端子は前記ヘッドエンドの遠隔制御用
の制御信号を発生するヘッドエンド操作盤に接続され、
かつ前記制御信号は前記ＣＡＴＶ伝送路の上り回線を介
して前記ヘッドエンド内蔵のヘッドエンド制御盤に供給
され、前記ヘッドエンド制御盤によって前記ヘッドエン
ドの出力する測定対象の所望の出力信号をオン／オフさ
せるとともに前記ＣＡＴＶ伝送路の下り回線を介して送
出する伝送信号を増幅する増幅器の増幅度を可変とさせ
ることを特徴とするＣＡＴＶシステムの歪測定方法。2. A C for transmitting an output signal output from a head end of a CATV system to a subscriber including a repeater.
C for measuring the distortion factor of the ATV transmission line for each type of output signal
In the distortion measurement method for an ATV system, a directional filter is connected to a monitor terminal of the repeater, and a high-pass terminal of the directional filter is connected to a spectrum analyzer via a bandpass filter and an auxiliary amplifier. Measuring the spectrum required for distortion factor measurement, the low-pass terminal of the directional filter is connected to a headend operation panel for generating a control signal for remote control of the headend,
Further, the control signal is supplied to the headend control board with the built-in headend via the upstream line of the CATV transmission line, and the headend control board turns on / off a desired output signal of the measurement object output from the headend. A distortion measuring method for a CATV system, characterized in that the amplification degree of an amplifier for amplifying a transmission signal transmitted through the downlink of the CATV transmission line is made variable while being turned off.
号が、ヘッドエンド内蔵の方向性フィルタの低域通過端
子を介して出力され、かつ前記方向性フィルタの高域通
過端子は前記増幅器の出力に接続されることを特徴とす
る請求項２記載のＣＡＴＶシステムの歪測定方法。3. The control signal input to the head end is output via a low pass terminal of a directional filter built in the head end, and a high pass terminal of the directional filter is output to the amplifier. The CATV system distortion measuring method according to claim 2, wherein the CATV system is connected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23527293A JPH0795545A (en) | 1993-09-22 | 1993-09-22 | Distortion measuring method for catv system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23527293A JPH0795545A (en) | 1993-09-22 | 1993-09-22 | Distortion measuring method for catv system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0795545A true JPH0795545A (en) | 1995-04-07 |
Family
ID=16983644
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23527293A Pending JPH0795545A (en) | 1993-09-22 | 1993-09-22 | Distortion measuring method for catv system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0795545A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020095933A (en) * | 2001-06-18 | 2002-12-28 | 엘지이노텍 주식회사 | Data send and reception system of spectrum alalyser |
| JP2006304234A (en) * | 2005-04-25 | 2006-11-02 | Matsushita Electric Works Ltd | Image transmission device |
-
1993
- 1993-09-22 JP JP23527293A patent/JPH0795545A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020095933A (en) * | 2001-06-18 | 2002-12-28 | 엘지이노텍 주식회사 | Data send and reception system of spectrum alalyser |
| JP2006304234A (en) * | 2005-04-25 | 2006-11-02 | Matsushita Electric Works Ltd | Image transmission device |
| JP4548200B2 (en) * | 2005-04-25 | 2010-09-22 | パナソニック電工株式会社 | Image transmission device |
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| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20000704 |