JP2953507B2 - Transmission line amplitude characteristic measurement device - Google Patents
Transmission line amplitude characteristic measurement deviceInfo
- Publication number
- JP2953507B2 JP2953507B2 JP8285267A JP28526796A JP2953507B2 JP 2953507 B2 JP2953507 B2 JP 2953507B2 JP 8285267 A JP8285267 A JP 8285267A JP 28526796 A JP28526796 A JP 28526796A JP 2953507 B2 JP2953507 B2 JP 2953507B2
- Authority
- JP
- Japan
- Prior art keywords
- signal
- transmission
- gps
- burst
- receiving
- 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 - Lifetime
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- Monitoring And Testing Of Transmission In General (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Description
【０００１】[0001]
【発明の属する技術分野】本発明は伝送路の振幅特性を
測定するシステムに関し、特に、伝送路の振幅特性を測
定するための遠端測定システムに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for measuring the amplitude characteristic of a transmission line, and more particularly to a far-end measurement system for measuring the amplitude characteristic of a transmission line.
【０００２】[0002]
【従来の技術】一般に、伝送路の振幅特性を測定する際
には、送信側から、同期信号付きのマルチバースト信号
を試験信号として伝送路に送出する。そして、受信側で
はこの同期信号を受信し同期信号に応じてマルチバース
トのゲート位置を決定して、必要とする信号を抜き取っ
てその振幅を測定している。2. Description of the Related Art Generally, when measuring the amplitude characteristic of a transmission line, a multi-burst signal with a synchronization signal is transmitted from the transmission side to the transmission line as a test signal. Then, the receiving side receives the synchronization signal, determines the gate position of the multi-burst according to the synchronization signal, extracts a necessary signal, and measures the amplitude.
【０００３】送信側でマルチバースト信号に重畳させる
同期信号として、一般に、パルス信号が用いられてお
り、パルス信号波形の所定の閾値から基準タイミングを
得てゲート信号を得ている。そして、このゲート信号に
応じてゲート位置を決定している。In general, a pulse signal is used as a synchronization signal to be superimposed on a multiburst signal on the transmission side, and a gate signal is obtained by obtaining a reference timing from a predetermined threshold value of a pulse signal waveform. The gate position is determined according to the gate signal.
【０００４】[0004]
【発明が解決しようとする課題】前述のように、従来の
伝送路振幅特性測定装置では、送信側でマルチバースト
信号に重畳させる同期信号はにパルス信号が用いられて
いるが、このパルス信号波形は、測定する伝送路の振幅
特性の影響を受ける。つまり、パルス信号波形は測定す
る伝送路の振幅特性に依存して変形してしまう（歪んで
しまう）。As described above, in the conventional transmission line amplitude characteristic measuring apparatus, a pulse signal is used as a synchronization signal to be superimposed on a multi-burst signal on the transmitting side. Is affected by the amplitude characteristics of the transmission path to be measured. That is, the pulse signal waveform is deformed (distorted) depending on the amplitude characteristic of the transmission path to be measured.
【０００５】一方、前述のように、ゲート信号を得る際
には、変形した（歪んだ）パルス信号波形の所定の閾値
から基準タイミングを得て、この基準タイミングに応じ
てゲート信号を生成しているから、ゲート位置を決定す
る際の時間軸の精度が劣化してしまうという問題点があ
る。On the other hand, as described above, when obtaining a gate signal, a reference timing is obtained from a predetermined threshold value of a deformed (distorted) pulse signal waveform, and a gate signal is generated in accordance with the reference timing. Therefore, there is a problem that the accuracy of the time axis when determining the gate position is deteriorated.
【０００６】つまり、従来の伝送路振幅特性測定装置で
は、マルチバースト信号から単一信号を抜き取るゲート
信号を正確に再生できないという問題点がある。That is, the conventional transmission line amplitude characteristic measuring apparatus has a problem that a gate signal that extracts a single signal from a multiburst signal cannot be accurately reproduced.
【０００７】本発明の目的は、マルチバースト信号から
単一信号を抜き取るゲート信号を正確に再生することの
できる伝送路振幅特性測定装置を提供することにある。An object of the present invention is to provide a transmission line amplitude characteristic measuring apparatus capable of accurately reproducing a gate signal that extracts a single signal from a multiburst signal.
【０００８】[0008]
【課題を解決するための手段】本発明では、受信端にお
けるタイミング再生の精度を上げるため、ゲート時間情
報としてＧＰＳ衛星の内部時刻基準を用いる。これによ
って、正確な基準種は数及び送受信点での正確な時間タ
イミングが得られる。According to the present invention, the internal time reference of the GPS satellite is used as gate time information in order to improve the accuracy of timing reproduction at the receiving end. This provides accurate reference species in number and accurate time timing at the transmit and receive points.
【０００９】つまり、本発明によれば、伝送路の振幅歪
み特性を測定する測定装置であって、ＧＰＳ衛星からの
ＧＰＳ信号を受け該ＧＰＳ信号に応じて送信側復調基準
信号を出力する送信側ＧＰＳ受信手段と、前記ＧＰＳ衛
星からの前記ＧＰＳ信号を受け該ＧＰＳ信号に応じて受
信側復調基準信号を出力する受信側ＧＰＳ受信手段と、
該送信側復調基準信号に応じて複数の信号が重畳された
マルチバースト信号を前記伝送路に送出するマルチバー
スト信号発生手段と、前記伝送路を介して前記マルチバ
スト信号を受け前記受信側復調基準信号に応じてゲート
信号を生成し該ゲート信号に基づいて前記マルチバスト
信号から前記信号を抜き取って前記伝送路の振幅測定を
行う測定手段とを有することを特徴とする伝送路振幅特
性測定装置が得られる。That is, according to the present invention, there is provided a measuring apparatus for measuring the amplitude distortion characteristic of a transmission line, which receives a GPS signal from a GPS satellite and outputs a demodulation reference signal on the transmitting side in accordance with the GPS signal. GPS receiving means, receiving-side GPS receiving means for receiving the GPS signal from the GPS satellite and outputting a receiving-side demodulation reference signal in accordance with the GPS signal;
Multi-burst signal generating means for transmitting to the transmission path a multi-burst signal in which a plurality of signals are superimposed according to the transmission-side demodulation reference signal; and receiving the multi-bust signal via the transmission path, A transmission line amplitude characteristic measuring device, comprising: a measuring unit that generates a gate signal in accordance with the signal, extracts the signal from the multi-bust signal based on the gate signal, and measures the amplitude of the transmission line. can get.
【００１０】前記ＧＰＳ信号には基準周波数及び前記Ｇ
ＰＳ衛星内の高安定時計に応じた基準時刻が含まれてお
り、前記マルチバースト信号発生手段は前記送信側復調
基準信号に同期した送信側タイミング信号を生成する位
相同期発振器と、該送信側タイミング信号に応じて動作
し前記マルチバースト信号を送出するマルチバースト発
生器とを有している。そして、前記マルチバースト発生
器は前記送信側タイミング信号に基づいて前記基準周波
数に同期して前記複数の信号を生成して前記基準時刻に
応じて順次前記複数の信号を送出して前記マルチバース
ト信号とする。The GPS signal includes a reference frequency and the G signal.
The multi-burst signal generation means includes a phase-locked oscillator for generating a transmission-side timing signal synchronized with the transmission-side demodulation reference signal, and a transmission-side timing. A multi-burst generator that operates in response to a signal and transmits the multi-burst signal. The multi-burst generator generates the plurality of signals in synchronization with the reference frequency based on the transmission-side timing signal, and sequentially transmits the plurality of signals in accordance with the reference time to generate the multi-burst signal. And
【００１１】一方、前記測定手段では前記受信側復調基
準信号に応じて前記マルチバースト信号の個別の信号を
抜き取る時刻タイミング信号を生成し該時刻タイミング
信号を前記ゲート信号とする。On the other hand, the measuring means generates a time timing signal for extracting the individual signals of the multiburst signal in accordance with the demodulation reference signal on the receiving side, and uses the time timing signal as the gate signal.
【００１２】このように、送信側ではＧＰＳ信号より得
られた基準周波数に同期した信号（例えば、正弦波信
号）を複数生成し、これらの信号を、ＧＰＳより得られ
た基準時刻ごとに送出し、必要なマルチバースト信号を
生成する。As described above, on the transmitting side, a plurality of signals (for example, sine wave signals) synchronized with the reference frequency obtained from the GPS signal are generated, and these signals are transmitted for each reference time obtained from the GPS. , Generate the required multiburst signal.
【００１３】受信端では、ＧＰＳ信号より検出した時刻
基準に基づいてゲート信号を得た後、このゲート信号に
基づいて必要な信号を抜き取る。そして、抜き取られた
信号の振幅を測定する。The receiving end obtains a gate signal based on a time reference detected from the GPS signal, and then extracts a necessary signal based on the gate signal. Then, the amplitude of the extracted signal is measured.
【００１４】[0014]
【発明の実施の形態】以下本発明について図面を参照し
て説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.
【００１５】図１を参照して、本発明による伝送路振幅
測定システムは、ＧＰＳ受信空中線１及び８、ＧＰＳ受
信機２及び９、位相同期発振器３、マルチバースト発生
器４、及び振幅測定器１０を備えており、図示の伝送路
振幅測定システムは伝送システムに接続される。Referring to FIG. 1, a transmission line amplitude measuring system according to the present invention comprises a GPS receiving antennas 1 and 8, GPS receivers 2 and 9, a phase locked oscillator 3, a multiburst generator 4, and an amplitude measuring device 10. , And the illustrated transmission line amplitude measurement system is connected to the transmission system.
【００１６】伝送システムは、アナログ系送信装置５及
びアナログ系受信装置７を備えており、アナログ系送信
装置５及びアナログ系受信装置７は伝送路６によって接
続されている。伝送路６の振幅特定を測定する際には、
マルチバースト発生器４がアナログ系送信装置５に接続
されるとともにアナログ系受信装置７には振幅測定器１
０が接続される。The transmission system includes an analog transmission device 5 and an analog reception device 7. The analog transmission device 5 and the analog reception device 7 are connected by a transmission line 6. When measuring the specific amplitude of the transmission path 6,
The multi-burst generator 4 is connected to the analog transmitter 5 and the analog receiver 7 has an amplitude measuring device 1.
0 is connected.
【００１７】ＧＰＳ受信空中線１及び８はＧＰＳ衛星
（図示せず）からのＧＰＳ信号を受信してそれぞれ送信
側及び受信側ＧＰＳ受信機２及び９にＧＰＳ信号を与え
る。そして、ＧＰＳ受信機２及び９ではＧＰＳ信号を復
調してそれぞれ送信側復調基準信号及び受信側復調基準
信号を得る。具体的には、ＧＰＳ衛星には高安定時計が
備えられており、ＧＰＳ信号にはこの高安定時計（内部
時計）による時刻情報が含まれている。従って、送信側
復調基準信号及び受信側復調基準信号はそれぞれＧＰＳ
衛星の内部時計に同期していることになる。The GPS receiving antennas 1 and 8 receive GPS signals from GPS satellites (not shown) and provide GPS signals to the transmitting and receiving GPS receivers 2 and 9, respectively. Then, the GPS receivers 2 and 9 demodulate the GPS signals to obtain a transmission-side demodulation reference signal and a reception-side demodulation reference signal, respectively. Specifically, a GPS satellite is provided with a highly stable clock, and the GPS signal includes time information based on the highly stable clock (internal clock). Therefore, the transmission-side demodulation reference signal and the reception-side demodulation reference signal are respectively GPS
It is synchronized with the satellite's internal clock.
【００１８】送信端において、位相同期発振器３は送信
側復調基準信号に同期して送信側タイミング信号を発生
しする。そして、マルチバースト発生器４はこの送信側
タイミング信号に応じて動作する。つまり、マルチバー
スト発生器４は、送信側タイミング信号に応じて、マル
チバースト信号を送出試験信号として送出する。具体的
はに、マルチバースト発生器４は送信側タイミング信号
に基づいてＧＰＳ信号の基準周波数に同期して複数の信
号を生成してＧＰＳ信号の基準時刻に応じて順次前記複
数の信号を送出してマルチバースト信号とする。At the transmitting end, the phase locked oscillator 3 generates a transmitting side timing signal in synchronization with the transmitting side demodulation reference signal. Then, the multi-burst generator 4 operates according to the transmission-side timing signal. That is, the multi-burst generator 4 transmits the multi-burst signal as a transmission test signal according to the transmission-side timing signal. Specifically, the multi-burst generator 4 generates a plurality of signals in synchronization with the reference frequency of the GPS signal based on the transmission-side timing signal, and sequentially transmits the plurality of signals in accordance with the reference time of the GPS signal. As a multi-burst signal.
【００１９】図２（Ａ）に送出試験信号の形態を示す。
図２（Ａ）に示すように、送出試験信号は周波数ｆ１か
らｆｎの正弦波信号がそれぞれ時刻ｔ１からｔｎで多重
されている。FIG. 2A shows a form of the transmission test signal.
As shown in FIG. 2A, in the transmission test signal, sine wave signals of frequencies f1 to fn are multiplexed at times t1 to tn, respectively.
【００２０】この送出試験信号はアナログ系送信装置５
によって伝送路６に送出され、アナログ系受信装置７に
よって受信される。そして、受信試験信号として振幅測
定器１０に与えられる。The transmission test signal is transmitted to the analog transmitting device 5.
Is transmitted to the transmission line 6 and received by the analog receiver 7. Then, it is provided to the amplitude measuring device 10 as a reception test signal.
【００２１】一方、前述のように、受信側ＧＰＳ受信機
９からは受信側復調基準信号が振幅測定器１０に与えら
れており、振幅測定器１０では受信側復調基準信号に基
づいて送出マルチバースト信号（受信試験信号）のゲー
ト位置を決定する。On the other hand, as described above, the receiving-side demodulation reference signal is given from the receiving-side GPS receiver 9 to the amplitude measuring device 10, and the amplitude measuring device 10 transmits the multi-burst signal based on the receiving-side demodulation reference signal. The gate position of the signal (reception test signal) is determined.
【００２２】例えば、周波数ｆ１の信号振幅を測定する
際には、図２（Ｂ）に示すタイミングパルスで周波数ｆ
１の信号を抜き取ることになる。つまり、受信側復調基
準信号に応じて受信側タイミング信号（ｆ１用ゲート信
号Ｔ１）を生成して、周波数ｆ１の信号を抜き取る。For example, when measuring the amplitude of the signal at the frequency f1, the timing f shown in FIG.
One signal will be extracted. That is, a reception-side timing signal (gate signal T1 for f1) is generated according to the reception-side demodulation reference signal, and a signal of the frequency f1 is extracted.
【００２３】なお、ｆ２以降の信号にっても同様にして
信号の抜き取りを行って、各信号の振幅測定を行い、伝
送系における振幅劣化状態を測定する。It is to be noted that signals are similarly extracted from the signals after f2, the amplitude of each signal is measured, and the state of amplitude deterioration in the transmission system is measured.
【００２４】[0024]
【発明の効果】以上説明したように、本発明では、伝送
路にタイミング信号を送出していないから、つまり、伝
送特性により測定波形が歪み、その結果、測定タイミン
グが変化して測定精度が変化することがないから、安定
して伝送路振幅の遠端測定ができるという効果がある。
しかもＧＰＳ衛星からのＧＰＳ信号に応じて伝送路振幅
を測定しているから、日本国内はもとより超長距離とな
る全世界を範囲とした正確な遠端振幅特性を測定するこ
とができるという効果もある。As described above, in the present invention, the timing signal is not transmitted to the transmission line, that is, the measurement waveform is distorted due to the transmission characteristics, and as a result, the measurement timing changes and the measurement accuracy changes. Therefore, there is an effect that the far-end measurement of the transmission path amplitude can be stably performed.
In addition, since the transmission path amplitude is measured in response to GPS signals from GPS satellites, the effect of being able to measure accurate far-end amplitude characteristics not only in Japan but also over the entire world, which is an extremely long distance. is there.
【００２５】さらに、本発明では、同期信号のガード期
間等の配慮が不要となり、測定用のバースト信号の数を
増やすことができるばかりでなく、周波数測定ポイント
数を増やすことができる。Further, according to the present invention, it is not necessary to consider the guard period of the synchronization signal and the like, so that not only the number of burst signals for measurement can be increased, but also the number of frequency measurement points can be increased.
【００２６】また、本発明では、制御用同期信号として
広帯域にわたるエネルギー成分を有するパルス状の同期
信号を用いていないから、同期パルスによる伝送路の飽
和現象等が避けることができる。Further, in the present invention, since a pulse-like synchronization signal having an energy component over a wide band is not used as the control synchronization signal, the saturation phenomenon of the transmission line due to the synchronization pulse can be avoided.
【図１】本発明による伝送路振幅測定装置の一例を説明
するためのブロック図である。FIG. 1 is a block diagram illustrating an example of a transmission line amplitude measuring apparatus according to the present invention.
【図２】送出試験信号（マルチバースト信号）とゲート
信号との関係を示す図であり、（Ａ）はマルチバースト
信号を示す図、（Ｂ）はゲート信号を示す図である。2A and 2B are diagrams illustrating a relationship between a transmission test signal (multi-burst signal) and a gate signal, wherein FIG. 2A is a diagram illustrating a multi-burst signal, and FIG. 2B is a diagram illustrating a gate signal.
１，８ ＧＰＳ受信空中線 ２，９ ＧＰＳ受信機 ３ 位相同期発振器 ４ マルチバースト発生器 ５ アナログ系送信装置 ６ 伝送路 ７ アナログ系受信装置 １０ 振幅測定器 1,8 GPS receiving antenna 2,9 GPS receiver 3 Phase locked oscillator 4 Multiburst generator 5 Analog transmitting device 6 Transmission line 7 Analog receiving device 10 Amplitude measuring device
Claims (4)
置であって、ＧＰＳ衛星からのＧＰＳ信号を受け該ＧＰ
Ｓ信号に応じて送信側復調基準信号を出力する送信側Ｇ
ＰＳ受信手段と、前記ＧＰＳ衛星からの前記ＧＰＳ信号
を受け該ＧＰＳ信号に応じて受信側復調基準信号を出力
する受信側ＧＰＳ受信手段と、該送信側復調基準信号に
応じて複数の信号が重畳されたマルチバースト信号を前
記伝送路に送出するマルチバースト信号発生手段と、前
記伝送路を介して前記マルチバスト信号を受け前記受信
側復調基準信号に応じてゲート信号を生成し該ゲート信
号に基づいて前記マルチバスト信号から前記信号を抜き
取って前記伝送路の振幅測定を行う測定手段とを有する
ことを特徴とする伝送路振幅特性測定装置。1. A measuring device for measuring an amplitude distortion characteristic of a transmission line, wherein the measuring device receives a GPS signal from a GPS satellite.
A transmitting side G that outputs a transmitting side demodulation reference signal according to the S signal
PS receiving means, receiving-side GPS receiving means for receiving the GPS signal from the GPS satellite and outputting a receiving-side demodulation reference signal according to the GPS signal, and superimposing a plurality of signals according to the transmitting-side demodulation reference signal Multi-burst signal generating means for transmitting the multi-burst signal to the transmission path, receiving the multi-bust signal via the transmission path, generating a gate signal in accordance with the receiving-side demodulation reference signal, and generating a gate signal based on the gate signal. Measuring means for extracting the signal from the multi-bust signal and measuring the amplitude of the transmission line.
定装置において、前記ＧＰＳ信号には基準周波数及び前
記ＧＰＳ衛星内の高安定時計に応じた基準時刻が含まれ
ており、前記マルチバースト信号発生手段は前記送信側
復調基準信号に同期した送信側タイミング信号を生成す
る位相同期発振器と、該送信側タイミング信号に応じて
動作し前記マルチバースト信号を送出するマルチバース
ト発生器とを有することを特徴とする伝送路振幅特性測
定装置。2. The transmission line amplitude characteristic measuring apparatus according to claim 1, wherein the GPS signal includes a reference frequency and a reference time according to a high-stability clock in the GPS satellite, and the multi-burst. The signal generation means includes a phase-locked oscillator that generates a transmission-side timing signal synchronized with the transmission-side demodulation reference signal, and a multi-burst generator that operates according to the transmission-side timing signal and transmits the multi-burst signal. A transmission line amplitude characteristic measuring device characterized by the following.
定装置において、前記マルチバースト発生器は前記送信
側タイミング信号に基づいて前記基準周波数に同期して
前記複数の信号を生成して前記基準時刻に応じて順次前
記複数の信号を送出して前記マルチバースト信号とする
ようにしたことを特徴とする伝送路振幅特性測定装置。3. The transmission line amplitude characteristic measuring device according to claim 2, wherein the multi-burst generator generates the plurality of signals in synchronization with the reference frequency based on the transmission-side timing signal. A transmission path amplitude characteristic measuring device, wherein the plurality of signals are sequentially transmitted in accordance with a reference time to form the multi-burst signal.
定装置において、前記測定手段では前記受信側復調基準
信号に応じて前記マルチバースト信号の個別の信号を抜
き取る時刻タイミング信号を生成し該時刻タイミング信
号を前記ゲート信号とするようにしたことを特徴とする
伝送路振幅特性測定装置。4. The transmission path amplitude characteristic measuring apparatus according to claim 3, wherein the measuring means generates a time timing signal for extracting an individual signal of the multi-burst signal in accordance with the receiving-side demodulation reference signal. A transmission path amplitude characteristic measuring device, wherein a time timing signal is used as the gate signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8285267A JP2953507B2 (en) | 1996-10-28 | 1996-10-28 | Transmission line amplitude characteristic measurement device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8285267A JP2953507B2 (en) | 1996-10-28 | 1996-10-28 | Transmission line amplitude characteristic measurement device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10132878A JPH10132878A (en) | 1998-05-22 |
| JP2953507B2 true JP2953507B2 (en) | 1999-09-27 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8285267A Expired - Lifetime JP2953507B2 (en) | 1996-10-28 | 1996-10-28 | Transmission line amplitude characteristic measurement device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2953507B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20030095124A (en) * | 2002-06-11 | 2003-12-18 | 조용범 | transmission line parameter measument device using synchronizing clock based on global positioning system |
| US9350470B1 (en) * | 2015-02-27 | 2016-05-24 | Keysight Technologies, Inc. | Phase slope reference adapted for use in wideband phase spectrum measurements |
-
1996
- 1996-10-28 JP JP8285267A patent/JP2953507B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH10132878A (en) | 1998-05-22 |
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