JP2002094490A - Time-supplying system and time-supplying device - Google Patents

Time-supplying system and time-supplying device

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Publication number
JP2002094490A
JP2002094490A JP2000275558A JP2000275558A JP2002094490A JP 2002094490 A JP2002094490 A JP 2002094490A JP 2000275558 A JP2000275558 A JP 2000275558A JP 2000275558 A JP2000275558 A JP 2000275558A JP 2002094490 A JP2002094490 A JP 2002094490A
Authority
JP
Japan
Prior art keywords
time
frequency
master
slave
supply device
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
Application number
JP2000275558A
Other languages
Japanese (ja)
Other versions
JP3538374B2 (en
Inventor
Taichi Hiramatsu
太一 平松
Shuichi Maruyama
秀一 丸山
Masami Kihara
雅巳 木原
賢浩 ▲芦▼
Masahiro Ashi
Takaaki Toyama
貴章 外山
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Nippon Telegraph and Telephone Corp
NTT Communications Corp
Original Assignee
Hitachi Ltd
Nippon Telegraph and Telephone Corp
NTT Communications Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd, Nippon Telegraph and Telephone Corp, NTT Communications Corp filed Critical Hitachi Ltd
Priority to JP2000275558A priority Critical patent/JP3538374B2/en
Publication of JP2002094490A publication Critical patent/JP2002094490A/en
Application granted granted Critical
Publication of JP3538374B2 publication Critical patent/JP3538374B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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  • Synchronisation In Digital Transmission Systems (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a technique for maintaining generation of accurate time, and for performing time synchronization, even when the supply of a time is interrupted for a long time. SOLUTION: This time supply system for supplying a reference time synchronizing with a time master is provided with a time-supplying device and a frequency-supplying device. The time-supplying device is provided with a means for receiving reference frequencies from the frequency-supplying device, and for generating a time based on the reference frequencies and a means for correcting the time, based on the reference time from the time master, and for generating a reference time synchronizing with the time master. The frequency-supplying device is provided with a means for generating the reference frequencies being synchronized with a frequency master.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、ネットワークから
基準となる時刻を受け、その時刻によりスケジュール管
理を行うようなアプリケーションに適用することを目的
に、信頼性の高い、安定な基準時刻を供給することを可
能にする時刻供給システムに関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a highly reliable and stable reference time for application to an application which receives a reference time from a network and performs schedule management based on the time. A time supply system that enables

【0002】[0002]

【従来の技術】ネットワークを使用して時刻を供給する
場合、時刻の基準となる秒信号と、時分秒などの時刻情
報の両方を、ネットワークを利用してマスタとなる時刻
供給装置からスレーブとなる時刻供給装置に転送する。
2. Description of the Related Art When supplying time using a network, both a time signal such as a second signal serving as a time reference and time information such as hour, minute, and second are transmitted from a time supplying apparatus serving as a master to a slave using the network. To a time supply device.

【0003】時刻情報が転送される伝送路が故障すると
時刻が停止してしまうが、これを防ぐために、従来技術
では、供給を受ける側の装置に独自に時刻を発生する回
路を設けて、時刻情報が途絶えた場合には独立に時刻を
発生することで時刻を維持している。
[0003] If the transmission line for transferring the time information fails, the time stops. In order to prevent this, in the prior art, a circuit that generates the time independently is provided in a device that receives the time. When information is lost, the time is maintained by generating the time independently.

【0004】[0004]

【発明が解決しようとする課題】しかしながら、上記の
従来技術では、独自に時刻を発生する回路によって短時
間であれば時刻を維持できるが、長時間の亘り時刻の供
給が途絶えた場合には、徐々に時刻精度が劣化してゆく
という問題点があった。
However, in the above-mentioned prior art, the time can be maintained for a short time by a circuit that independently generates time, but when the supply of time is interrupted for a long time, There was a problem that the time accuracy gradually deteriorated.

【0005】本発明は上記の点に鑑みてなされたもので
あり、時刻の供給が長時間途絶えた場合であっても、正
確な時刻の発生を維持し、時刻同期を可能とする時刻同
期システム及び時刻供給装置を提供することを目的とす
る。
[0005] The present invention has been made in view of the above points, and a time synchronization system that maintains accurate time generation and enables time synchronization even when supply of time is interrupted for a long time. And a time supply device.

【0006】[0006]

【課題を解決するための手段】請求項1に記載の発明
は、時刻マスタに同期した基準時刻を供給する時刻供給
システムであって、時刻供給装置と周波数供給装置とを
有し、該時刻供給装置は、前記周波数供給装置から基準
周波数を受信し、その基準周波数に基づき時刻を発生す
る手段と、その時刻を時刻マスタからの基準時刻を基に
して補正し、時刻マスタに同期した基準時刻を発生する
手段とを有する。
According to a first aspect of the present invention, there is provided a time supply system for supplying a reference time synchronized with a time master, comprising a time supply device and a frequency supply device. The device receives a reference frequency from the frequency supply device, generates a time based on the reference frequency, and corrects the time based on a reference time from a time master, and calculates a reference time synchronized with the time master. Generating means.

【0007】基準時刻情報と基準周波数を、時刻供給装
置に別々に供給するので、基準時刻情報が途絶えても、
基準周波数の供給は受けられるので、これをもとに時刻
を発生することが可能となる。
Since the reference time information and the reference frequency are separately supplied to the time supply device, even if the reference time information is interrupted,
Since the supply of the reference frequency can be received, the time can be generated based on the reference frequency.

【0008】請求項2に記載の発明は、請求項1の記載
において、前記周波数供給装置は、周波数マスタに同期
した基準周波数を発生する手段を有するようにする。
According to a second aspect of the present invention, in the first aspect, the frequency supply device has means for generating a reference frequency synchronized with a frequency master.

【0009】本発明によれば、周波数供給装置から安定
した基準周波数を供給することができる。
According to the present invention, a stable reference frequency can be supplied from the frequency supply device.

【0010】請求項3に記載の発明は、請求項2の記載
において、前記時刻マスタからの基準時刻が異常な場合
には、前記時刻供給装置は正常時の補正値に基づき前記
時刻を補正し、前記周波数マスタからの基準周波数が異
常な場合には、前記周波数供給装置は正常時の基準周波
数を維持する。
According to a third aspect of the present invention, in the second aspect, when the reference time from the time master is abnormal, the time supply device corrects the time based on a normal time correction value. If the reference frequency from the frequency master is abnormal, the frequency supply device maintains the normal reference frequency.

【0011】本発明によれば、基準周波数の供給が途絶
えた場合でも、維持された基準周波数によって時刻を発
生することができる。
According to the present invention, the time can be generated by the maintained reference frequency even when the supply of the reference frequency is interrupted.

【0012】請求項4に記載の発明は、時刻マスタに同
期した基準時刻を供給する時刻供給システムであって、
基準時刻を維持する時刻マスタと、時刻マスタに同期す
る時刻スレーブと、時刻マスタと時刻スレーブとの間で
時刻情報を転送する時刻用伝送路と、基準周波数を維持
する周波数マスタと、周波数マスタに同期する周波数ス
レーブと、周波数マスタと周波数スレーブとの間で周波
数情報を転送する周波数用伝送路とを有し、前記時刻ス
レーブは前記周波数スレーブから基準周波数を受けて基
準時刻を発生する。
The invention according to claim 4 is a time supply system for supplying a reference time synchronized with a time master,
A time master that maintains a reference time, a time slave that synchronizes with the time master, a time transmission path that transfers time information between the time master and the time slave, a frequency master that maintains a reference frequency, and a frequency master It has a frequency slave to be synchronized and a frequency transmission line for transferring frequency information between the frequency master and the frequency slave. The time slave receives a reference frequency from the frequency slave and generates a reference time.

【0013】本発明によっても、上記と同様の作用効果
を奏する。
According to the present invention, the same operation and effect as described above can be obtained.

【0014】請求項5に記載の発明は、時刻マスタに同
期した基準時刻を供給する時刻供給装置であって、周波
数供給装置から基準周波数を受信し、その基準周波数に
基づき時刻を発生する手段と、その時刻を時刻マスタか
らの基準時刻を基にして補正し、時刻マスタに同期した
基準時刻を発生する手段とを有する。
According to a fifth aspect of the present invention, there is provided a time supply device for supplying a reference time synchronized with a time master, comprising a means for receiving a reference frequency from a frequency supply device and generating a time based on the reference frequency. Means for correcting the time based on the reference time from the time master and generating a reference time synchronized with the time master.

【0015】請求項6に記載の発明は、請求項5の記載
において、前記時刻マスタからの基準時刻が異常な場合
には、正常時の補正値に基づき前記時刻を補正する。
According to a sixth aspect of the present invention, when the reference time from the time master is abnormal, the time is corrected based on a normal correction value.

【0016】請求項5、6の発明によっても、前記の時
刻供給システムと実質的に同様の作用効果を奏する。
According to the fifth and sixth aspects of the invention, substantially the same operation and effect as those of the above time supply system can be obtained.

【0017】[0017]

【発明の実施の形態】図1に本発明の一実施例における
時刻同期システムの構成図を示す。
FIG. 1 shows a configuration diagram of a time synchronization system according to an embodiment of the present invention.

【0018】同図に示すように、伝送局1にある時刻マ
スタ3(マスタとして機能する時刻供給装置を時刻マス
タと称する)と、伝送局5にある時刻スレーブ7(スレ
ーブとして機能する時刻供給装置を時刻スレーブと称す
る)は、時刻用伝送路9で接続され、時刻マスタ3が発
生する基準時刻が時刻スレーブ7に転送される。
As shown in FIG. 1, a time master 3 (a time supply device functioning as a master is referred to as a time master) in a transmission station 1 and a time slave 7 (a time supply device functioning as a slave) in a transmission station 5. Are referred to as a time slave) via a time transmission line 9, and the reference time generated by the time master 3 is transferred to the time slave 7.

【0019】上記と同様に、周波数マスタ11(マスタ
として機能する周波数供給装置を周波数マスタと称す
る)と周波数スレーブ13(スレーブとして機能する周
波数供給装置を周波数スレーブと称する)は、周波数用
伝送路15で接続され、周波数マスタ11が発生する基
準周波数が周波数スレーブ13に転送される。
Similarly to the above, the frequency master 11 (the frequency supply device functioning as a master is called a frequency master) and the frequency slave 13 (the frequency supply device functioning as a slave is called a frequency slave) are connected to the frequency transmission line 15. And the reference frequency generated by the frequency master 11 is transferred to the frequency slave 13.

【0020】本発明においては、時刻スレーブ7は、周
波数スレーブ13で同期・再生された基準周波数を受
け、基準1秒信号を発生する。なお、前述した基準時刻
とは基準1秒信号等の基準信号を含む情報をいう。基準
1秒信号は、時刻マスタ3からの時刻情報で補正され
る。これにより時刻スレーブ7からは、補正され時刻マ
スタ3に同期した基準1秒信号と、時刻マスタ3から転
送された時刻情報が出力される。なお、ある伝送局にお
いて、時刻スレーブと周波数スレーブとを合わせて時刻
供給システムと称する。又は、時刻マスタと周波数マス
タとをこれに含めて時刻供給システムと称してもよい。
In the present invention, the time slave 7 receives the reference frequency synchronized and reproduced by the frequency slave 13 and generates a reference 1 second signal. Note that the above-mentioned reference time refers to information including a reference signal such as a reference 1 second signal. The reference one-second signal is corrected based on the time information from the time master 3. As a result, the time slave 7 outputs the corrected one-second reference signal synchronized with the time master 3 and the time information transferred from the time master 3. In a certain transmission station, a time slave and a frequency slave are collectively referred to as a time supply system. Alternatively, the time master and the frequency master may be included in these and referred to as a time supply system.

【0021】上記のように、時刻スレーブは、周波数ス
レーブから基準周波数を供給されるので、時刻マスタ3
からの基準1秒信号が途絶えた場合であっても、その基
準周波数に基づき、基準1秒信号を生成し、出力するこ
とができる。
As described above, the time slave is supplied with the reference frequency from the frequency slave.
Even if the reference one-second signal from is interrupted, the reference one-second signal can be generated and output based on the reference frequency.

【0022】次に、各装置の詳細について説明する。Next, details of each device will be described.

【0023】図2に、時刻マスタ3と時刻スレーブ7を
有する時刻転送システムの構成を示す。このシステムに
より時刻が転送される。
FIG. 2 shows the configuration of a time transfer system having a time master 3 and a time slave 7. The time is transferred by this system.

【0024】時刻マスタ3は、時刻情報と基準1秒信号
を出力するマスタ時計17、信号の送受信を行う伝送端
局装置19、時刻差を測定する時刻差測定器21を有す
る。
The time master 3 has a master clock 17 for outputting time information and a reference 1 second signal, a transmission terminal device 19 for transmitting and receiving signals, and a time difference measuring device 21 for measuring a time difference.

【0025】時刻スレーブ7は、基準周波数と時刻差が
入力され時刻情報と基準1秒信号を出力するスレーブ時
計23、信号の送受信を行う伝送端局装置25、時刻差
を測定する時刻差測定器27を有する。次に動作を説明
する。
The time slave 7 receives a reference frequency and a time difference, outputs a time information and a reference 1 second signal, a slave clock 23, a transmission / reception terminal device 25 for transmitting / receiving a signal, and a time difference measuring device for measuring the time difference. 27. Next, the operation will be described.

【0026】マスタ時計17からの基準1秒信号は2系
統出力される。片方の基準1秒信号は、送信基準1秒信
号として、伝送端局装置19の送信部29により、時刻
スレーブ7に転送される。もうひとつの基準1秒信号は
時刻差測定器21に入力される。
The reference one-second signal from the master clock 17 is output in two systems. One of the reference one-second signals is transferred to the time slave 7 by the transmission unit 29 of the transmission terminal device 19 as a transmission reference one-second signal. Another one-second reference signal is input to the time difference measuring device 21.

【0027】時刻スレーブ7においては、スレーブ時計
23の2系統の出力が、伝送端局装置25と時刻差測定
器27に入力される。
In the time slave 7, two outputs of the slave clock 23 are input to the transmission terminal device 25 and the time difference measuring device 27.

【0028】時刻マスタ3における時刻差測定器21で
は、時刻スレーブからの受信基準1秒信号と時刻マスタ
3の送信基準1秒信号との時刻差が測定され時刻差デー
タT1が得られる。また、時刻スレーブ7における時刻
差測定器27では、時刻マスタ3からの受信基準1秒信
号と時刻スレーブ7の送信基準1秒信号との時刻差が測
定され時刻差データT2が得られる。このT1は時刻マ
スタ3から時刻スレーブ7に送信され、時刻スレーブ7
ではT1とT2を用いて時刻を補正する。その詳細を次
に説明する。
The time difference measuring device 21 of the time master 3 measures the time difference between the one-second reception reference signal from the time slave and the one-second transmission reference signal of the time master 3, and obtains time difference data T1. The time difference measuring device 27 in the time slave 7 measures the time difference between the one-second reception reference signal from the time master 3 and the one-second transmission reference signal of the time slave 7, and obtains time difference data T2. This T1 is transmitted from the time master 3 to the time slave 7, and the time slave 7
Then, the time is corrected using T1 and T2. The details will be described below.

【0029】図3に秒信号間の時間関係を示す。上述の
ように、T1は、マスタ時計17からの送信基準1秒信
号(1PPS−MS)と、スレーブ時計23からの受信
基準1秒信号(1PPS−SR)との時刻差であり、T
2は、スレーブ時計23からの送信基準1秒信号(1P
PS−SS)と、マスタ時計17からの受信基準1秒信
号(1PPS−MR)との時刻差である。
FIG. 3 shows the time relationship between the second signals. As described above, T1 is the time difference between the transmission reference 1 second signal (1PPS-MS) from the master clock 17 and the reception reference 1 second signal (1PPS-SR) from the slave clock 23.
2 is a transmission reference 1 second signal (1P
PS-SS) and the time difference between the one-second reception reference signal (1PPS-MR) from the master clock 17.

【0030】図3に示すように、時刻マスタ3から時刻
スレーブ7までの伝送遅延時間はt1、逆方向の遅延時
間はt2で示される。tlとt2が等しい場合、(T1
−T2)/2(図3におけるΔ)はマスタ時計とスレー
ブ時計の時刻差を表す。
As shown in FIG. 3, the transmission delay time from the time master 3 to the time slave 7 is represented by t1, and the delay time in the reverse direction is represented by t2. If tl and t2 are equal, (T1
−T2) / 2 (Δ in FIG. 3) represents a time difference between the master clock and the slave clock.

【0031】時刻マスタ3で計測されたT1は、伝送端
局装置間の通信機能により、時刻マスタ3から時刻スレ
ーブ7に転送され、時刻差測定器27において上記の演
算が行われる。これにより、時刻スレーブ7での時刻差
測定器27は、マスタ時計とスレーブ時計の時刻差デー
タを出力することができる。この時刻差データにより、
スレーブ時計23は時刻を補正することができる。な
お、補正は例えば定期的に行うようにすることができ
る。
The time T1 measured by the time master 3 is transferred from the time master 3 to the time slave 7 by the communication function between the transmission terminal devices, and the above-described calculation is performed in the time difference measuring device 27. Thereby, the time difference measuring device 27 in the time slave 7 can output the time difference data between the master clock and the slave clock. With this time difference data,
The slave clock 23 can correct the time. The correction can be performed periodically, for example.

【0032】次に、周波数転送について説明する。Next, frequency transfer will be described.

【0033】図4に、周波数転送システムの構成を示
す。周波数マスタ11は、基準周波数を発生するマスタ
発振器33と伝送端局装置35を有する。また、周波数
スレーブ13は、スレーブ発信器37と伝送端局装置3
9を有する。
FIG. 4 shows the configuration of the frequency transfer system. The frequency master 11 has a master oscillator 33 for generating a reference frequency and a transmission terminal device 35. The frequency slave 13 includes a slave transmitter 37 and the transmission terminal device 3.
9

【0034】周波数マスタ11内のマスタ発振器33で
発生される基準周波数は、伝送端局装置35の送信部4
1により、周波数スレーブ13内の受信部43へ転送さ
れ、さらにスレーブ発振器37に入力される。スレーブ
発振器37は、位相同期発振器45により構成され、入
力された基準周波数に位相同期する。スレーブ発振器出
力は、周波数スレーブ出力の基準周波数となる。
The reference frequency generated by the master oscillator 33 in the frequency master 11
1 is transferred to the receiving unit 43 in the frequency slave 13, and further input to the slave oscillator 37. The slave oscillator 37 is constituted by a phase locked oscillator 45, and performs phase synchronization with the input reference frequency. The slave oscillator output becomes the reference frequency of the frequency slave output.

【0035】図5に、スレーブ発振器37を構成する位
相同期発振器45の構成を示す。位相同期発振器45
は、ディジタル位相比較器47、信号異常検出回路4
9、ディジタルフィルタ51、ディジタル制御発振器5
3を有する。また、ディジタルフィルタ51はディジタ
ル値保持プロセス55を有する。
FIG. 5 shows the configuration of the phase-locked oscillator 45 constituting the slave oscillator 37. Phase locked oscillator 45
Is a digital phase comparator 47, a signal abnormality detection circuit 4
9, digital filter 51, digitally controlled oscillator 5
3 The digital filter 51 has a digital value holding process 55.

【0036】このようなディジタル型の位相同期回路に
より、周波数スレーブで発生される基準周波数は、周波
数マスタ11からの基準周波数に異常が発生しても一定
期間周波数を維持することができる。すなわち、周波数
マスタからの基準周波数に異常が発生した場合、信号異
常検出回路49は、ディジタル値保持プロセス55を起
動し、ディジタル制御発振器53の制御を停止し、その
直前の値を保持する。これにより、ディジタル制御発振
器53の自走時周波数安定度に応じた基準周波数精度が
維持される。
With such a digital phase-locked loop, the reference frequency generated by the frequency slave can be maintained for a certain period even if the reference frequency from the frequency master 11 becomes abnormal. That is, when an abnormality occurs in the reference frequency from the frequency master, the signal abnormality detection circuit 49 starts the digital value holding process 55, stops the control of the digital control oscillator 53, and holds the value immediately before. As a result, the reference frequency accuracy corresponding to the free-running frequency stability of the digitally controlled oscillator 53 is maintained.

【0037】図6に、スレーブ時計23の構成を示す。
スレーブ時計23は、分周回路57、カウンタ回路5
9、時刻情報訂正回路61を有する。分周回路57は、
周波数スレーブ13からの基準周波数を受け、1秒信号
を発生する。カウンタ回路59は、分周回路57から1
秒信号を受け、時刻差測定器27から送られるマスタ時
計17とスレーブ時計23の時刻差データ(上記のT1
とT2)をもとに、この1秒信号を補正し、マスタ時計
17に同期した基準1秒信号を出力する。時刻情報訂正
回路61は、時刻差測定器27から送られる時刻情報
を、カウンタ回路59での1秒信号の補正に合わせて訂
正し、時刻情報を出力する。
FIG. 6 shows the configuration of the slave clock 23.
The slave clock 23 includes a frequency dividing circuit 57 and a counter circuit 5
9, a time information correction circuit 61 is provided. The dividing circuit 57
It receives a reference frequency from the frequency slave 13 and generates a one-second signal. The counter circuit 59 is provided by
Receiving the second signal, the time difference data between the master clock 17 and the slave clock 23 sent from the time difference measuring device 27 (T1
And T2), the 1-second signal is corrected, and a reference 1-second signal synchronized with the master clock 17 is output. The time information correction circuit 61 corrects the time information sent from the time difference measuring device 27 in accordance with the correction of the one-second signal by the counter circuit 59, and outputs the time information.

【0038】本発明は、上記の実施例に限定されること
なく、特許請求の範囲内で種々変更・応用が可能であ
る。
The present invention is not limited to the above embodiment, but can be variously modified and applied within the scope of the claims.

【0039】[0039]

【発明の効果】本発明によれば、時刻情報と基準周波数
(クロック)を、別々に供給するので、伝送路が故障し
て時刻情報が途絶えても、別途基準周波数が供給される
こととなり、長時間に亘りこの基準周波数を基にして正
確な基準時刻を発生することができ、この基準時刻を基
にして通信網における装置間の時刻同期を維持すること
が可能となる。
According to the present invention, the time information and the reference frequency (clock) are separately supplied. Therefore, even if the transmission path fails and the time information is interrupted, the reference frequency is separately supplied. An accurate reference time can be generated based on the reference frequency for a long time, and time synchronization between devices in a communication network can be maintained based on the reference time.

【0040】すなわち、時刻同期システムにおいて、時
刻マスタ3からの基準時刻が、時刻用伝送路9の故障な
どで途絶えた場合、時刻スレーブ7は基準時刻を受けら
れなくなる。このような場合でも、周波数スレーブ13
からの基準周波数により1秒信号は発生できるので、時
刻スレーブ7は、故障発生直前の補正値を保持すること
で、基準1秒信号、時刻情報ともに出力し続けることが
できる。
That is, in the time synchronization system, when the reference time from the time master 3 is interrupted due to a failure of the time transmission line 9, the time slave 7 cannot receive the reference time. Even in such a case, the frequency slave 13
Since the one-second signal can be generated based on the reference frequency from, the time slave 7 can keep outputting the reference one-second signal and the time information by holding the correction value immediately before the occurrence of the failure.

【0041】更に、周波数用伝送路15が故障で、基準
周波数が途絶えた場合にも、周波数スレーブの周波数維
持機能により、基準周波数が維持される。周波数スレー
ブ13内のディジタル制御発振器53としては、ルビジ
ウム原子発振器が使用可能であり、その場合、周波数は
5×10−11/月以内に保持される。
Further, even when the frequency transmission line 15 fails and the reference frequency is interrupted, the reference frequency is maintained by the frequency maintenance function of the frequency slave. As the digitally controlled oscillator 53 in the frequency slave 13, a rubidium atomic oscillator can be used, in which case the frequency is maintained within 5 × 10 −11 / month.

【0042】従って、この状態で基準1秒信号が出力さ
れても、故障直前の時刻、周波数が正確であれば、1ケ
月間1ナノ秒以内の誤差に時刻を維持することは十分に
可能である。
Therefore, even if the reference 1 second signal is output in this state, if the time and frequency immediately before the failure are accurate, it is sufficiently possible to maintain the time within an error of 1 nanosecond for one month. is there.

【0043】このように、本発明による時刻同期システ
ムは、地理的に離れた場所の間で、信頼性の高い時刻同
期を可能にすることができる。
As described above, the time synchronization system according to the present invention enables highly reliable time synchronization between geographically distant places.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の一実施例における時刻同期システムの
構成図である。
FIG. 1 is a configuration diagram of a time synchronization system according to an embodiment of the present invention.

【図2】時刻転送システムの構成図である。FIG. 2 is a configuration diagram of a time transfer system.

【図3】秒信号間の時間関係を示す図である。FIG. 3 is a diagram showing a time relationship between second signals.

【図4】周波数転送システムの構成図である。FIG. 4 is a configuration diagram of a frequency transfer system.

【図5】位相同発振器の構成図である。FIG. 5 is a configuration diagram of the same-phase oscillator.

【図6】スレーブ時計の構成図である。FIG. 6 is a configuration diagram of a slave clock.

【符号の説明】[Explanation of symbols]

1、5 伝送局 3 時刻マスタ 7 時刻スレーブ 9 時刻用伝送路 11 周波数マスタ 13 周波数スレーブ 15 周波数用伝送路 17 マスタ時計 19、25、35、37 伝送端局装置 21、27 時刻差測定器 23 スレーブ時計 33 マスタ発振器 37 スレーブ発振器 45 位相同期発振器 47 ディジタル位相比較器 49 信号検出回路 51 ディジタルフィルタ 53 ディジタル制御発振器 55 ディジタル値保持プロセス 57 分周回路 59 カウンタ回路 61 時刻情報訂正回路 1, 5 Transmission station 3 Time master 7 Time slave 9 Time transmission line 11 Frequency master 13 Frequency slave 15 Frequency transmission line 17 Master clock 19, 25, 35, 37 Transmission terminal station device 21, 27 Time difference measuring device 23 Slave Clock 33 master oscillator 37 slave oscillator 45 phase-locked oscillator 47 digital phase comparator 49 signal detection circuit 51 digital filter 53 digital control oscillator 55 digital value holding process 57 frequency divider 59 counter circuit 61 time information correction circuit

───────────────────────────────────────────────────── フロントページの続き (72)発明者 平松 太一 東京都千代田区内幸町一丁目1番6号 エ ヌ・ティ・ティ・コミュニケーションズ株 式会社内 (72)発明者 丸山 秀一 東京都千代田区内幸町一丁目1番6号 エ ヌ・ティ・ティ・コミュニケーションズ株 式会社内 (72)発明者 木原 雅巳 東京都千代田区大手町二丁目3番1号 日 本電信電話株式会社内 (72)発明者 ▲芦▼ 賢浩 神奈川県横浜市戸塚区戸塚町216番地 株 式会社日立製作所通信事業部内 (72)発明者 外山 貴章 神奈川県横浜市戸塚区戸塚町216番地 株 式会社日立製作所通信事業部内 Fターム(参考) 2F002 AA00 AF01 FA16 GA06 5K047 AA11 AA18 GG02 GG09 GG10 GG11 GG56  ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Taichi Hiramatsu 1-6-6 Uchisaiwaicho, Chiyoda-ku, Tokyo NTT Communications Corporation (72) Inventor Shuichi Maruyama One-Uchiyukicho, Chiyoda-ku, Tokyo No. 1-6, NTT Communications Corporation (72) Inventor Masami Kihara 2-3-1, Otemachi, Chiyoda-ku, Tokyo Japan Telegraph and Telephone Co., Ltd. (72) Inventor ▲ Ash ▼ Tomohiro 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Hitachi, Ltd. Communications Division (72) Inventor Takaaki Toyama 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture F-term in the Hitachi, Ltd. Communications Division (Reference) 2F002 AA00 AF01 FA16 GA06 5K047 AA11 AA18 GG02 GG09 GG10 GG11 GG56

Claims (6)

【特許請求の範囲】[Claims] 【請求項1】 時刻マスタに同期した基準時刻を供給す
る時刻供給システムであって、 時刻供給装置と周波数供給装置とを有し、 該時刻供給装置は、 前記周波数供給装置から基準周波数を受信し、その基準
周波数に基づき時刻を発生する手段と、 その時刻を時刻マスタからの基準時刻を基にして補正
し、時刻マスタに同期した基準時刻を発生する手段とを
有することを特徴とする時刻供給システム。
1. A time supply system for supplying a reference time synchronized with a time master, comprising a time supply device and a frequency supply device, wherein the time supply device receives a reference frequency from the frequency supply device. Means for generating a time based on the reference frequency, and means for correcting the time based on the reference time from the time master and generating a reference time synchronized with the time master. system.
【請求項2】 前記周波数供給装置は、 周波数マスタに同期した基準周波数を発生する手段を有
する請求項1に記載の時刻供給システム。
2. The time supply system according to claim 1, wherein the frequency supply device has a unit that generates a reference frequency synchronized with a frequency master.
【請求項3】 前記時刻マスタからの基準時刻が異常な
場合には、前記時刻供給装置は正常時の補正値に基づき
前記時刻を補正し、 前記周波数マスタからの基準周波数が異常な場合には、
前記周波数供給装置は正常時の基準周波数を維持する請
求項2に記載の時刻供給システム。
3. When the reference time from the time master is abnormal, the time supply device corrects the time based on a normal time correction value, and when the reference frequency from the frequency master is abnormal, ,
The time supply system according to claim 2, wherein the frequency supply device maintains a normal reference frequency.
【請求項4】 時刻マスタに同期した基準時刻を供給す
る時刻供給システムであって、 基準時刻を維持する時刻マスタと、 時刻マスタに同期する時刻スレーブと、 時刻マスタと時刻スレーブとの間で時刻情報を転送する
時刻用伝送路と、 基準周波数を維持する周波数マスタと、 周波数マスタに同期する周波数スレーブと、 周波数マスタと周波数スレーブとの間で周波数情報を転
送する周波数用伝送路とを有し、 前記時刻スレーブは前記周波数スレーブから基準周波数
を受けて基準時刻を発生することを特徴とする時刻供給
システム。
4. A time supply system for supplying a reference time synchronized with a time master, wherein the time master maintains the reference time, a time slave synchronized with the time master, and a time between the time master and the time slave. It has a time transmission line for transferring information, a frequency master for maintaining a reference frequency, a frequency slave synchronized with the frequency master, and a frequency transmission line for transferring frequency information between the frequency master and the frequency slave. A time supply system, wherein the time slave generates a reference time by receiving a reference frequency from the frequency slave.
【請求項5】 時刻マスタに同期した基準時刻を供給す
る時刻供給装置であって、 周波数供給装置から基準周波数を受信し、その基準周波
数に基づき時刻を発生する手段と、 その時刻を時刻マスタからの基準時刻を基にして補正
し、時刻マスタに同期した基準時刻を発生する手段とを
有することを特徴とする時刻供給装置。
5. A time supply device for supplying a reference time synchronized with a time master, comprising: means for receiving a reference frequency from a frequency supply device and generating a time based on the reference frequency; Means for making a correction based on the reference time and generating a reference time synchronized with the time master.
【請求項6】 前記時刻マスタからの基準時刻が異常な
場合には、正常時の補正値に基づき前記時刻を補正する
請求項5に記載の時刻供給装置。
6. The time supply device according to claim 5, wherein when the reference time from the time master is abnormal, the time is corrected based on a normal correction value.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010141759A (en) * 2008-12-15 2010-06-24 Softbank Mobile Corp Reference signal generating device, and apparatus employing the same
JP2011523320A (en) * 2008-06-13 2011-08-04 アルカテル−ルーセント A method for delivering a common time base within a distributed architecture
JP2013118502A (en) * 2011-12-02 2013-06-13 Mitsubishi Electric Corp Time synchronization apparatus, radio terminal and time synchronization system
JP2016119548A (en) * 2014-12-19 2016-06-30 ファナック株式会社 Time synchronization system for communication devices
JP2017079445A (en) * 2015-10-22 2017-04-27 ソフトバンク株式会社 Signal output device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05134062A (en) * 1991-11-11 1993-05-28 Toshiba Corp Time synchronizing method for process monitoring apparatus
JPH05134779A (en) * 1991-05-18 1993-06-01 Fuji Facom Corp Calender ic correction method
JPH05216557A (en) * 1992-02-04 1993-08-27 Nec Corp System for switching between external clock for computer and internal clock
JP2001221874A (en) * 2000-02-14 2001-08-17 Toshiba Corp Time synchronization system
JP2002071854A (en) * 2000-09-04 2002-03-12 Nippon Telegr & Teleph Corp <Ntt> Standard radio wave receiver

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05134779A (en) * 1991-05-18 1993-06-01 Fuji Facom Corp Calender ic correction method
JPH05134062A (en) * 1991-11-11 1993-05-28 Toshiba Corp Time synchronizing method for process monitoring apparatus
JPH05216557A (en) * 1992-02-04 1993-08-27 Nec Corp System for switching between external clock for computer and internal clock
JP2001221874A (en) * 2000-02-14 2001-08-17 Toshiba Corp Time synchronization system
JP2002071854A (en) * 2000-09-04 2002-03-12 Nippon Telegr & Teleph Corp <Ntt> Standard radio wave receiver

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011523320A (en) * 2008-06-13 2011-08-04 アルカテル−ルーセント A method for delivering a common time base within a distributed architecture
JP2010141759A (en) * 2008-12-15 2010-06-24 Softbank Mobile Corp Reference signal generating device, and apparatus employing the same
JP2013118502A (en) * 2011-12-02 2013-06-13 Mitsubishi Electric Corp Time synchronization apparatus, radio terminal and time synchronization system
JP2016119548A (en) * 2014-12-19 2016-06-30 ファナック株式会社 Time synchronization system for communication devices
JP2017079445A (en) * 2015-10-22 2017-04-27 ソフトバンク株式会社 Signal output device

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