JPH07159556A - Satellite-utilized clock calibrating system - Google Patents

Abstract

PURPOSE:To provide a satellite-corrected clock calibrating system allowing a plurality of clocks to continuously display invariably accurate time without requiring troublesome manual calibration or the line installation work. CONSTITUTION:Radio waves 12 emitted from an artificial satellite such as a position measuring satellite and containing accurate time are received by a master clock AMC at every fixed time interval via an antenna 13, the satellite time is reproduced from the received radio waves, and the time of the master clock is calibrated by the satellite time. The data indicating the calibrated accurate time are transmitted to a plurality of slave clocks ASC1-ASC6 via small-power radio waves at a fixed time interval respectively. The time data of the master clock AMC are extracted from the received radio waves in the slave clocks ASC1-ASC6 respectively, the internal time of the slave clocks ASC1-ASC6 is automatically calibrated by the time data, and the calibrated accurate time is displayed at time display sections.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes time information in radio waves emitted by artificial satellites such as positioning satellites that generate accurate time internally, and uses the time information of one or more buildings or railways. Automatically set the time of multiple clocks distributed at stations, etc.
The present invention also relates to a satellite-based clock calibration system that can be accurately calibrated.

[0002]

2. Description of the Related Art A plurality of clocks are always arranged in a distributed manner in general homes, buildings, factories, railway stations, etc., and the time of these clocks is conventionally operated and calibrated by the following method. (1) If the time is displayed independently at the place where each clock is installed, such as a general wall clock or table clock, another time that is said to be displaying the correct time during calibration Based on a clock, Nippon Telegraph and Telephone Corporation (N
TT) time signal service or time information of public electric wave broadcasting such as TV / radio is used as a reference, and the time of each clock is adjusted at the time of installation, and then it is calibrated periodically. (2) When there are many clocks such as buildings, factories, railway stations, etc., and they are arranged over a wide area (distributed arrangement), as described in (1) above, The time may be displayed independently at the place where the clock is installed (in this case, the calibration method in (1) above will be used), but it usually takes the form of a parent-child clock system. . In the case of the parent-child clock system, a time signal generated by the parent clock is transmitted to a plurality of child clocks by wire, and each child clock receives the time signal and displays the time. There are the following two main methods of transmitting the time signal from the master clock to the slave clock.

Timing signal (1 second excluding date,
30 seconds, 1 minute, etc.) only. How to send year / month / day / hour / minute / second data.

[0004]

In the calibration method of the above item (1), a human is sensuously manually performing the calibration work both when the watch is installed and when the periodic calibration is performed. Therefore, the calibration work is troublesome and it is difficult to perform accurate calibration. Further, the regular calibration interval time cannot be observed, and it is common to notice after the time is delayed (or advance) and then to calibrate. Moreover, when it is necessary to calibrate the time, it is often the case that the life schedule is hindered because the time delay is not noticed.

In the case of the calibration method of the above item (2), periodic calibration is not required for each child clock, but it takes time and cost to construct a line for supplying a timing signal from the parent clock to the child clock. , It increases in proportion to the number of clocks installed. In addition, line extension work is required when adding child clocks. Furthermore, since the master clock supplies only the timing signals of 1 second, 30 seconds, 1 minute, etc. excluding the year / month / day, to the child clock, it is necessary to manually calibrate the year / month / day / time etc. when the clock is installed. .

In the case of the calibration method of the above item (2), similar to the above case, the periodical calibration in each sub-clock is unnecessary, but similarly, the data signal of year / month / day / hour / minute / second is sent from the master clock to the sub-clock. It takes time and money to lay the line to supply the clock, and it is necessary to add the line when the child clock is added. On the other hand, unlike the above case, there is no need to manually calibrate the date and time when installing the clock, but since the master clock supplies a complicated data signal of the date and time to the slave clock, the transmission system However, there is a problem that it becomes complicated.

An object of the present invention is to receive radio waves emitted by an artificial satellite such as a positioning satellite which is operated by using an accurate standard time, in a master clock so that the accurate time can be obtained periodically by a plurality of slave clocks. A satellite-based clock calibration system that enables the child clock to continue to display accurate time at all times without the need for troublesome manual calibration work and line laying work, etc. To do.

[0008]

According to the present invention, an antenna for receiving a radio wave including an accurate time emitted from an artificial satellite such as a positioning satellite is installed, and the antenna is transmitted through the antenna at regular time intervals. A clock receives radio waves from an artificial satellite, reproduces the satellite time from the received radio waves, calibrates the time of the master clock with the satellite time, and the data representing the calibrated time is transmitted to a plurality of children at fixed time intervals. Each timepiece is transmitted by radio wave, and the time inside the child clock is automatically calibrated by the time data from the parent clock received by each child clock.

[0009]

According to the above configuration of the present invention, the time of the master clock is automatically calibrated by the accurate time from the artificial satellite,
Also, since each child clock is automatically calibrated by the accurate time data by the radio wave from the parent clock, no calibration by troublesome manual adjustment is required, and the displayed time becomes extremely accurate. Moreover, since time data is transmitted from the parent clock to each child clock at fixed time intervals, which is a low-power radio wave, line laying work for transmitting the time data is completely unnecessary and power consumption is extremely low. . further,
There is no need to install additional lines when adding child clocks.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram showing one embodiment of a satellite-based clock calibration system according to the present invention. For example, a positioning satellite is provided on the roof of a general home where a plurality of clocks are installed, a building, a factory, a station, etc. The antenna 13 for receiving the radio wave 12 including the accurate time emitted from the artificial satellite 11 is installed. Of course, the antenna 13
May be installed on the ground near the building.

For example, the positioning satellite NAV currently in operation now
STAR / GPS (Navigation System with Time and Ra
nging / Global Positioning System)
Radio waves emitted from PS satellites are received on the earth, and by measuring the distance between the satellite and the receiver from the difference between the time of the receiver and the satellite time obtained from the radio waves, the intersection of the equidistant curved surfaces can be determined. By asking for it, positioning of the receiving point becomes possible.
However, since the measured time difference is minute, the frequency of the radio wave emitted by the satellite needs to be extremely stable.
Therefore, most positioning satellites currently in operation are equipped with cesium or rubidium atomic frequency standard. Moreover, these satellites generate time in the satellite by using the atomic frequency standard as the oscillation source and send the data to the ground every moment. Further, the frequencies of these atomic frequency standards in the satellite and the times generated based on them are constantly calibrated by monitoring the deviation from the global standard by the satellite operation management organization on the ground. Therefore, by using the time information of these satellites, the extremely accurate time can always be obtained. Further, since it is predicted that not only positioning satellites but also mobile communication satellites will have positioning functions in the future, it is likely that the number of artificial satellites that provide time information will increase, and it will be easier to use.

In the building 10, one master clock AMC and a plurality of (six in this example) slave clocks ASC1, ASC2, AS are provided.
C3, ASC4, ASC5 and ASC6 are distributed. Although the master clock AMC is arranged in the attic of the building 10 and the six slave clocks ASC1 to ASC6 are respectively arranged in six rooms in the figure, the present invention is not limited to this. The master clock AMC receives the radio wave 12 from the artificial satellite 11 at regular time intervals through the antenna 13 and reproduces the satellite time from the received radio wave to reproduce the master clock AMC.
Is automatically calibrated with the satellite time, and the data representing the calibrated time is transmitted to each slave clock ASC1 to ASC6 by radio waves from the antenna provided in the master clock AMC at a certain time interval. Has been done.

FIG. 2 is a block diagram showing a structure of the master clock AMC. As shown in the figure, the master clock AMC is composed of a satellite radio wave reception unit 21, a satellite time reproduction unit 22, an internal clock 23, a time data transmission unit 24, and an antenna 25.
The satellite radio wave receiver 21 is an antenna 1 installed in the building 10.
The transmission code is decoded from the satellite radio wave 12 received through 3 and sent to the satellite time reproduction unit 22. Satellite time playback unit 2
2 extracts time data from the transmission code supplied from the satellite radio wave reception unit 21. However, since the time generated by most artificial satellites is the universal standard time (UT), it is necessary to convert the time to the local time such as Japan Standard Time (JST), and the satellite time reproduction unit 22 has this conversion function. .
For example, when converting to Japanese Standard Time [JST = UT +
9 hours]. The time data converted into the local time is sent to the internal clock 23. The internal clock 23 has a function of generating time by itself, and further has a function of automatically calibrating the time of occurrence with the time data from the satellite time reproducing unit 22, and the calibrated time data is used as the time data. It is sent to the transmission unit 24. The time data transmission unit 24 modulates a carrier wave of a predetermined frequency with the time data supplied from the internal clock 23, and converts the carrier wave into a low-power radio wave. This small electric wave is transmitted as time data 26 from the antenna 25 provided in the master clock AMC to each slave clock in the building.

On the other hand, each child clock, as shown in the block diagram of FIG. 3, has an antenna 31 for receiving a small electric wave (time data) 26 transmitted from the antenna 25 of the master clock AMC. The radio wave receiving unit 32 that decodes the transmission code from the low power radio wave received by the antenna 31, the time reproducing unit 33 that extracts the time data from the transmission code supplied from the radio wave receiving unit 32, and generates the time by itself. And an internal clock 34 having a function of calibrating the time of occurrence periodically and automatically by the time data supplied from the time reproduction unit 33, and the time of day generated by the internal clock 34 by analog type or It comprises a digital time display section 35 (in the figure, an analog display is shown).

According to the above configuration, the master clock AMC receives the radio wave 12 including the accurate time emitted from the artificial satellite 11 at every certain time interval, and the satellite time reproducing section 22 uses the received radio wave to calculate the satellite time. Is reproduced to calibrate the time of the master clock with this satellite time, and the data representing the calibrated time is transmitted from the time data transmitting unit 24 to the plurality of slave clocks ASC1 to ASC6 at a constant time interval by a small electric wave. can do. On the other hand, in each of the sub timepieces ASC1 to ASC6, the time data of the master timepiece is extracted from the radio wave received by the time reproduction section 33, the time inside the subclock is automatically calibrated with this time data, and the time display section 35 is used. The exact time can be displayed.

Therefore, the time of the master clock AMC is the artificial satellite 1
It is automatically calibrated by the correct time from 1
Since each child clock ASC1 to ASC6 is also automatically calibrated by the accurate time data by the radio wave from the master clock, the displayed time becomes extremely accurate, and the troublesome manual adjustment is not necessary. Moreover, since it is only necessary to lay the line for connecting the antenna 13 for receiving the radio wave 12 from the artificial satellite 11 and the master timepiece main body, the laying work is very easy, and the laying work from the master clock is performed. Since the time data is transmitted with a small electric power and is transmitted to each child clock at a certain fixed time interval, no line laying work for transmitting the time data is required, and the power consumption is extremely low. Furthermore, it is not necessary to perform line expansion work when adding child clocks.

NAVSTAR orbiting multiple satellites
When a system such as / GPS is used, satellites can be captured almost all day, but the timepiece system according to the present invention can maintain time accuracy with an accuracy of 1 second or less.
It is sufficient to receive satellite radio waves at a time interval of about once a day and calibrate the internal clock 23 of the master clock AMC. Therefore, the master clock needs only to receive the satellite radio waves for a few minutes at an arbitrary time set by the timer, and thus consumes little power. The relationship between the master clock and the slave clock is that, like a cordless telephone for general household use, the slave clock is always waiting for reception, and the calibration operation is performed when the master clock sends time data once a day by radio waves. I do. With this operation method, the entire system can be operated with low power consumption.

The above embodiment is merely an example of the present invention, and the installation locations (positions) of the antenna and the master clock for receiving satellite radio waves, the configurations of the master clock and the slave clock, etc. may be changed as necessary. Needless to say, it can be changed. Further, the present invention can be applied to not only wall-mounted clocks and table clocks but also wrist watches. That is, if the satellite radio wave reception antenna and the master clock described above are installed at home, the wristwatch has the function of the slave clock described above, and the calibration time of the master clock is set to, for example, midnight, it is possible to return after returning home every day. Since the time on the wristwatch is automatically calibrated during the night, you can go out with a wristwatch that displays the correct time next morning. Also, if you stay at a house with the same system without returning to your own house,
Similarly, accurate calibration can be performed automatically.

Further, in addition to wrist watches, wall clocks and table clocks, there are many clocks in general households.
For example, TVs, VCRs, stereos, electric rice cookers, electric washing machines, microwave ovens, etc. also have built-in clocks, and even if these clocks go astray, their life schedule will be hindered. Therefore, if such a timepiece with built-in home electric appliances is provided with the function of the child clock described above according to the present invention (the satellite radio wave reception antenna and the parent clock described above are installed at home), all the times in the home are unified. It can be managed and calibrated at any time, eliminating the need for manual time calibration. In addition to the automatic calibration function, if you have a function that allows you to perform calibration at any time, immediately after recovery from a power outage or breaker break, you can adjust the clocks here and there that everyone has experienced. It is possible to realize a very convenient and effective function that all the clocks can be instantly set to the standard time with one switch without the need.

[0020]

As described above, according to the present invention, the time of the master clock is automatically calibrated by the accurate time from the artificial satellite 11 which internally generates an accurate time like a positioning satellite. Also, since each child clock is automatically calibrated with accurate time data from the radio waves from this parent clock, the display time of each child clock is always extremely accurate,
Moreover, no tedious manual adjustment is required. Further, since each child clock and the master clock are connected by a wireless line, the time data from the master clock can be transmitted to each child clock by a small electric wave. In addition, calibration of the master clock with satellite radio waves may be done once a day at a time interval,
Since the master clock needs to be operated only during that time, power consumption is extremely low, and no line laying work for transmitting time data is required. In addition, there are many remarkable effects such as no need for additional line construction when adding child clocks.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a satellite-based clock calibration system according to the present invention.

FIG. 2 is a block diagram showing an example of the configuration of the master clock of FIG.

FIG. 3 is a block diagram showing an example of a configuration of a child timepiece shown in FIG.

[Explanation of symbols]

 10 building 11 artificial satellite 13 antenna AMC master clock ASC slave clock 21 satellite radio receiver 22 satellite time replay 23 internal clock 24 time data transmitter 25, 31 antenna 32 radio receiver 33 time replay 34 internal clock 35 time display

Claims (3)

[Claims] 1. A master clock and a plurality of slave clocks are provided,
Radio waves including an accurate time emitted from an artificial satellite are received by the master clock at certain constant time intervals, satellite time is reproduced from the received radio waves, and the time of the master clock is calibrated with the satellite time, Data indicating the calibrated time is transmitted to each of the plurality of child clocks by radio waves at a certain time interval, and the time data from the parent clock received by each child clock is used to automatically calibrate the time inside the child clock. A satellite-based clock calibration system characterized by: 2. The master clock, a satellite radio wave receiving unit that decodes the transmission code of the radio wave of the artificial satellite received through an antenna installed in a building, and time data from the transmission code from the satellite radio wave receiving unit. An internal clock having a satellite time reproducing unit for extracting, a function for generating time by itself, and a function for automatically calibrating the occurrence time with time data from the satellite time reproducing unit, and an internal clock Modulate a carrier wave of a predetermined frequency with the time data of
2. The satellite clock calibrating according to claim 1, comprising a time data transmitting unit for converting into a low-power radio wave, and an antenna for transmitting the low-power radio wave as time data to each child clock. system. 3. Each of the child clocks has an antenna for receiving a radio wave representing time data transmitted from the master clock, a radio wave receiving section for decoding a transmission code from the radio wave received by the antenna, and the radio wave receiving section. The time reproduction unit that extracts the time data from the transmission code from and the function that generates the time by itself, and the time data supplied from the time reproduction unit periodically and automatically calibrates the generation time. The satellite-based clock calibrating system according to claim 1, comprising an internal clock having a function of: and a time display section for displaying a time generated by the internal clock.