JP5114936B2 - Clock device and leap second correction method - Google Patents

Description

  The present invention relates to a timepiece device and a leap second correction method.

  Conventionally, there has been a GPS device that receives a GPS signal from a GPS (Global Positioning System) satellite and measures its own position. A GPS signal transmitted from a GPS satellite includes a C / A code (Coarse / Acquisition code). The C / A code includes navigation data (navigation message) indicating the orbit of the GPS satellite.

  The C / A code is a code in which different values are assigned to 28 GPS satellites. Therefore, the GPS device can select the GPS satellite and receive the GPS signal by collating the C / A code of the GPS satellite to be received with the C / A codes in the GPS signals received simultaneously. The GPS device also includes a clock unit that measures the current time and outputs the current time data (hereinafter referred to as internal time data).

  The GPS receiver selects three or four GPS satellites from receivable GPS satellites, and measures the position of the own aircraft based on the navigation data of the GPS signals received from the selected GPS satellites and the internal time data To do.

  In addition, the navigation data includes accurate time information of an atomic clock mounted on the transmission source GPS satellite.

  A technique for correcting the internal time of the GPS device using time information included in the navigation data is considered. In addition, a configuration has been considered in which leap second correction data for leap seconds included in the navigation data is used to correct leap second correction of the timekeeping unit of the GPS device (see, for example, Patent Documents 1 and 2).

Specifically, when the GPS device calculates the position information of its own device based on the received navigation data, the GPS device also calculates the current time correction information based on the time information in the navigation data, The data was corrected and the leap second was corrected based on the leap second correction data in the received navigation data. However, in portable devices such as electronic watches with GPS function, it is not always possible to continuously acquire information from GPS satellites, such as limiting the time that can be measured continuously, or stopping measurement after positioning once, considering battery consumption. It was.
JP 2002-365385 A JP 2001-228271 A

  However, since the conventional electronic timepiece with GPS function has a limitation on the GPS measurement time in consideration of battery consumption as described above, the leap second correction data transmitted only once every 12.5 minutes from the GPS satellite is surely obtained. If the leap second correction data could not be received when the leap second was inserted instead of being able to be received, there was a problem that the internal time data of the timekeeping part was shifted by the second when the leap second was inserted. .

  An object of the present invention is to reliably receive leap second correction data and correct leap seconds.

In order to solve the above problems, the timepiece device of the present invention includes:
A timekeeping means that keeps the current time as internal time data ,
Receiving means for receiving navigation data transmitted from a GPS satellite ;
First acquisition means for acquiring each subframe and page identification information and time information from the navigation data received by the reception means ;
Receiving time calculation for calculating the time until receiving leap second correction data included in the subframes after the subframe from the identification information and time information of the subframe and page acquired by the first acquisition unit Means,
The reception time calculating means includes
A reception timing value calculating means for calculating a reception timing value using each identification information of a subframe and a page;
Reception timing value determination means for determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and from the updated reception timing value and time information First setting means for setting a time until receiving leap second correction data;
If the reception timing value is not less than a predetermined time, the second setting means for setting the time until reception of leap second correction data from the reception timing value and time information,
Based on the time until receiving the leap second correction data calculated by the reception time calculation means, a reception timing determination means for determining whether or not the reception timing for receiving the leap second correction data is reached ;
When it is determined by the reception timing determination means that it is time to receive the leap second correction data, the reception means receives the navigation data, and the reception data is included in the subframe included in the received navigation data. A second acquisition means for acquiring second correction data ;
Leap second correction control means for correcting the leap second of the internal time data of the time measuring means based on the leap second correction data acquired by the second acquisition means ;
It is characterized by providing.

The timepiece device of the present invention includes:
A timekeeping means that keeps the current time as internal time data,
Receiving means for receiving navigation data transmitted from a GPS satellite;
First acquisition means for acquiring each subframe and page identification information and time information from the navigation data received by the reception means;
Based on the identification information and time information of the subframe and page acquired by the first acquisition means, the leap second correction data acquisition timing of the leap second correction data included in the other subframe is acquired. Acquisition timing calculation means for calculating as timing ;
The acquisition timing calculation means includes
A reception timing value calculating means for calculating a reception timing value using each identification information of a subframe and a page;
Reception timing value determination means for determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and the updated reception timing value and time information are obtained. A first setting means for setting the leap second correction data acquisition timing based on:
A second setting means for setting the leap second correction data acquisition timing based on the reception timing value and the time information when the reception timing value is not less than a predetermined time;
Immediately before reaching the leap second correction data acquisition timing calculated by the acquisition timing calculation means, the reception means receives the navigation data, and the leap second correction data included in the subframe in the received navigation data is received. A second acquisition means for acquiring ;
Leap second correction control means for correcting leap seconds of the internal time data of the time measuring means based on the leap second correction data acquired by the second acquisition means;
It is characterized by providing.

The timepiece device of the present invention includes:
A timekeeping means that keeps the current time as internal time data,
Receiving means for receiving navigation data transmitted from a GPS satellite;
First acquisition means for acquiring each subframe and page identification information and time information from the navigation data received by the reception means;
Receiving time calculation for calculating the time until receiving leap second correction data included in the subframes after the subframe from the identification information and time information of the subframe and page acquired by the first acquisition unit Means,
The reception time calculating means includes
A reception timing value calculating means for calculating a reception timing value using each identification information of a subframe and a page;
Reception timing value determination means for determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and from the updated reception timing value and time information First setting means for setting a time until receiving leap second correction data;
If the reception timing value is not less than a predetermined time, the second setting means for setting the time until reception of leap second correction data from the reception timing value and time information,
A setting timing discriminating means for discriminating whether or not the time indicated by the internal time data of the time measuring means has reached a setting timing for receiving preset leap second correction data;
When it is determined by the setting timing determining means that the setting timing for receiving the leap second correction data has been reached, the receiving means receives the navigation data and is included in the subframe in the received navigation data. A second acquisition means for acquiring leap second correction data;
Leap second correction control means for correcting the leap second of the internal time data of the time measuring means based on the leap second correction data acquired by the second acquisition means;
It is characterized by providing.

The leap second correction method of the present invention includes:
A first receiving step of receiving navigation data transmitted from a GPS satellite;
A first acquisition step of acquiring identification information and time information of each subframe and page from the navigation data received in the first reception step;
Receiving time calculation for calculating the time taken to receive leap second correction data included in subframes after the subframe from the identification information and time information of the subframe and page acquired in the first acquisition step. Process ,
The reception time calculating step includes
A reception timing value calculating step of calculating a reception timing value using identification information of each subframe and page;
A reception timing value determination step of determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and from the updated reception timing value and time information A first setting step of setting a time until receiving leap second correction data;
If the reception timing value is not less than a predetermined time, a second setting step of setting a time until reception of leap second correction data from the reception timing value and time information,
A reception timing determination step for determining whether it is a reception timing for receiving the leap second correction data, based on the time until the leap second correction data calculated in the reception time calculation step is received;
A second reception step of receiving navigation data when it is determined that the timing for receiving the leap second correction data is reached in this reception timing determination step;
A second acquisition step of acquiring leap second correction data included in the subframe in the navigation data received in the second reception step;
Based on the leap second correction data acquired in the second acquisition step, the leap second correction control step of correcting the leap second of the internal time data of the time measuring means that measures the current time and holds it as internal time data;
It is characterized by including.

The leap second correction method of the present invention includes:
A first receiving step of receiving navigation data transmitted from a GPS satellite;
A first acquisition step of acquiring identification information and time information of each subframe and page from the navigation data received in the first reception step;
Based on the identification information and time information of each subframe and page acquired in the first acquisition step, the leap second correction data acquisition timing for acquiring leap second correction data included in other subframes is acquired. An acquisition timing calculation step to calculate as timing ;
The acquisition timing calculation step includes
A reception timing value calculating step of calculating a reception timing value using identification information of each subframe and page;
A reception timing value determination step of determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and the updated reception timing value and time information are obtained. A first setting step for setting the leap second correction data acquisition timing based on:
A second setting step for setting a leap second correction data acquisition timing based on the reception timing value and the time information when the reception timing value is not less than a predetermined time; and
A second reception step of receiving navigation data immediately before reaching the leap second correction data acquisition timing calculated in the acquisition timing calculation step;
A second acquisition step of acquiring leap second correction data included in the subframe in the navigation data received in the second reception step;
Based on the leap second correction data acquired in the second acquisition step, the leap second correction control step of correcting the leap second of the internal time data of the clock means that measures the current time and holds it as internal time data;
It is characterized by including.

The leap second correction method of the present invention includes:
A first receiving step of receiving navigation data transmitted from a GPS satellite;
A first acquisition step of acquiring the identification information and time information of each subframe and page from the navigation data received by the first reception step;
Receiving time calculation for calculating the time from reception of leap second correction data included in subframes subsequent to the subframe from the identification information and time information of the subframe and page acquired in the first acquisition step. Process,
The reception time calculating step includes
A reception timing value calculating step of calculating a reception timing value using identification information of each subframe and page;
A reception timing value determination step of determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and from the updated reception timing value and time information A first setting step of setting a time until receiving leap second correction data;
If the reception timing value is not less than a predetermined time, a second setting step of setting a time until reception of leap second correction data from the reception timing value and time information,
A setting timing determination step for determining whether or not the time indicated by the internal time data of the time measuring means for measuring the current time and holding it as internal time data has reached a setting timing for receiving preset leap second correction data;
A second receiving step for receiving navigation data when it is determined that the setting timing for receiving the leap second correction data is reached in the setting timing determining step ;
A second acquisition step of acquiring leap second correction data included in the subframe in the navigation data received in the second reception step;
A leap second correction control step of correcting the leap second of the internal time data of the time measuring means based on the leap second correction data acquired by the second acquisition step;
It is characterized by including.

  According to the first and tenth aspects of the present invention, when the reception timing of leap second correction data is reached, leap second correction data can be reliably received to correct leap seconds.

According to the second aspect of the present invention, the reception timing can be easily determined.

According to the third aspect of the present invention, the reception timing can be easily determined.

According to the invention of claim 4, leap second correction data can be received with a margin, and leap second correction data can be received more reliably.

According to the fifth aspect of the present invention, since receiving and acquiring leap second correction data is repeated, any leap second correction data can be reliably acquired without leaking.

According to the sixth and eleventh aspects of the present invention, when the leap second correction data comes immediately before the reception timing of the leap second correction data, the leap second correction data can be reliably received and the leap second can be corrected.

According to the seventh and twelfth aspects of the invention, since the leap second correction data is received at the set timing, the leap second correction data can be reliably received and the leap second correction data can be received. Can be reduced, and power consumption can be reduced.

According to the eighth aspect of the invention, the number of leap second corrections can be further reduced, and the power consumption can be further reduced.

According to the ninth aspect of the invention, since the leap second correction is performed at the correction timing, the leap second can be reliably corrected at an appropriate timing.

  Hereinafter, preferred first and second embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the illustrated example.

(First embodiment)
A first embodiment according to the present invention will be described with reference to FIGS. First, the apparatus configuration of the present embodiment will be described with reference to FIG. FIG. 1 shows an internal configuration of the timepiece device 100 according to the present embodiment. The timepiece device 100 is an electronic timepiece with a GPS function, receives a GPS signal from a GPS satellite, and measures and displays an accurate current time.

  The timepiece device 100 includes a CPU (Central Processing Unit) 11, a display drive circuit 12, a display unit 13, a buzzer circuit 14, a speaker 15, a battery 16, an antenna 17a, a GPS module 17, and an operation unit 18. A ROM (Read Only Memory) 19, a storage unit 20, a RAM (Random Access Memory) 21, an illumination drive circuit 22, an illumination unit 23, and a timer unit 24. The timer unit 24 includes an oscillation circuit 25, a frequency dividing circuit 26, and a clock count circuit 27.

  The CPU 11 expands a program designated from the system program and various application programs stored in the ROM 19 in the RAM 21 and executes various processes in cooperation with the program expanded in the RAM 21.

  The CPU 11 calculates a leap second correction data acquisition timing T indicating the timing of receiving leap second correction data when receiving navigation data in cooperation with a first leap second correction program to be described later. When the acquisition timing T-30 seconds, navigation data is received and leap second correction data is acquired, and when leap second insertion timing S is reached, leap second correction is performed using leap second correction data.

  The display drive circuit 12 generates a display drive signal based on the display signal input from the CPU 11 and outputs the display drive signal to the display unit 13 to drive the display unit 13 for display. The display unit 13 includes a small LCD (Liquid Crystal Display), an ELD (ElectroLuminescent Display), and the like, and displays various types of information based on a display drive signal input from the display drive circuit 12. For example, the display unit 13 digitally displays the internal time data measured by the time measuring unit 24 as the current time.

  The buzzer circuit 14 generates a buzzer sound signal such as an alarm sound based on a control signal input from the CPU 11, outputs it to the speaker 15, and causes the speaker 15 to sound. The speaker 15 outputs a buzzer sound based on the sound signal input from the buzzer circuit 14.

  The battery 16 supplies power to each part of the timepiece device 100 such as the CPU 11. The GPS module 17 receives a GPS signal (navigation data) from a (visible) GPS satellite at a position where the timepiece device 100 can receive a GPS signal via the antenna 17 a and outputs the GPS signal (navigation data) to the CPU 11. The navigation data will be described later.

  The operation unit 18 includes various buttons, and outputs operation signals for various operation inputs made by the operator via the various buttons to the CPU 11. The various operations include, for example, changing various display modes, light emission of the illumination unit 23, and the like.

  The ROM 19 is a read-only memory that stores various programs and data. The storage unit 20 is configured by a flash memory or the like, and is a non-volatile memory that stores various data in a readable / writable manner. The RAM 21 is a volatile memory having a work area for storing various programs and data in a readable / writable manner. Specific information stored in the ROM 19, the storage unit 20, and the RAM 21 will be described later.

  The illumination drive circuit 22 generates an illumination drive signal based on the control signal input from the CPU 11 and outputs the illumination drive signal to the illumination unit 23 to turn on the illumination unit 23. The illuminating unit 23 is an illuminating unit that illuminates the display unit 13 such as an LED (Light Emitting Diode) or an EL, and lights up based on an illumination drive signal input from the illumination drive circuit 22.

  The timekeeping unit 24 is a circuit group that performs timekeeping, which is a main function as a clock. The oscillation circuit 25 is configured by, for example, a crystal oscillator or the like, and is a circuit that outputs a clock signal having a constant frequency to the frequency dividing circuit 26 at all times. The frequency divider circuit 26 is a circuit that counts the clock signal input from the oscillation circuit 25 and outputs a one-minute signal to the clock count circuit 27 every time the count value becomes a value corresponding to one minute. The clock count circuit 27 is a circuit that counts and holds internal time data such as the date of the day and the current hour / minute / second based on the one-minute signal input from the frequency divider 26.

  With these configurations, the timer unit 24 can count the date / time of the current year / month / day / hour / minute / second indicated by the internal time data, and outputs the internal time data to the CPU 11. Based on the internal time data, the CPU 11 controls the display drive circuit 12 and the display unit 13 to display the current time on the display unit 13.

  Next, various types of information stored in the timepiece device 100 will be described with reference to FIG. FIG. 2A shows a storage area for storing information in the ROM 19 in the present embodiment. FIG. 2B shows a storage area for storing information in the storage unit 20. FIG. 2C shows a storage area for storing information in the RAM 21.

  As shown in FIG. 2A, the ROM 19 has a program area 191 and a data area 192. The program area 191 stores a first leap second correction program (data). The data area 192 stores data representing formulas (1) and (2), which will be described later, for calculating the leap second correction data acquisition timing T and the leap second insertion timing S.

  As illustrated in FIG. 2B, the storage unit 20 includes data areas 201 to 203. The data area 201 stores almanac data that is orbit information of all GPS satellites. The data area 202 stores an internal processing time that is time information from when the time information is received until the time information is reflected in the internal time data. Almanac data and internal processing time are information used for time correction processing. The data area 203 stores a margin time for receiving leap second correction data with a margin from a leap second correction data acquisition timing T described later. The margin time is described as 30 seconds, but is not limited to this, and may be another time such as one minute.

  As shown in FIG. 2C, the RAM 21 has a program area 211 and data areas 212 to 217. In the program area 211, the first leap second correction program (data) is developed. The data area 212 stores time information in the received navigation data. The data area 213 stores the page number of the subframe in the received navigation data. The data area 214 stores a subframe number in the received navigation data. The data area 215 stores the calculated leap second correction data acquisition timing T. The data area 216 stores leap second correction data in the received navigation data. The data area 217 stores the calculated leap second insertion timing.

  Next, the outline of GPS and the contents of navigation data will be described with reference to FIGS.

  A part in the outer space of the entire GPS system is called a space segment, a ground part is called a control segment, and a user receiver is called a user segment. GPS satellites belong to the space segment. The GPS satellite is not a geostationary satellite, but orbits the altitude of 20,000 km and changes its position with respect to the earth. The space and control segments are developed and operated by the US military, but the user segment must be designed and manufactured by the user. Therefore, the specification of the signal transmitted from the GPS satellite is defined in detail and the document is made public. This document is named an Interface Control Document (abbreviated as ICD). The version of this ICD has been updated, for example, GPS-ICD-200.

  Currently, radio signals (GPS signals) are transmitted from 28 GPS satellites. The frequency of a radio signal transmitted by a GPS satellite is basically 1575.42 MHz (name: L1 wave), and a signal called a C / A code for civil use is placed on this frequency.

  FIG. 3 shows the format of the navigation data. FIG. 3A shows the frame structure of the navigation data. FIG. 3B shows a subframe configuration of navigation data. The navigation data having the format shown in FIG. 2 is described by the C / A code and transmitted as a GPS signal from a GPS satellite. The navigation data includes trajectory information, time information, and the like. The data rate of the navigation data is 50 bps.

  One cycle of the navigation data is called in units of frames and has the structure shown in FIG. One frame is 1500 bits. In a GPS satellite, it takes 30 seconds to transmit one frame. The frame is composed of five subframes (300 bits each), and transmission is started in order from subframe 1. When transmission of subframe 5 is completed, transmission returns to transmission of subframe 1 again.

  FIG. 4 shows a schematic configuration of the subframe. As shown in FIG. 4, among the five subframes constituting the frame, subframes 1 to 3 include clock correction information and orbit information (ephemeris) of the transmitting GPS satellite itself. For subframes 4 and 5, all satellites transmit the same contents, and the contents are rough orbit information (almanac) and ionosphere correction information of all GPS satellites (up to 32 satellites) in orbit. However, since these have a large amount of data, they are further divided into pages and accommodated in subframes.

  That is, as shown in FIG. 3A, the data transmitted in the subframes 4 and 5 are divided into pages 1 to 25, and the contents of different pages are sequentially transmitted for each frame. It takes 25 frames to transmit all page contents, and it takes 12 minutes and 30 seconds (12.5 minutes) to get all the navigation data information.

  The inside of the subframe is divided into units called words as shown in FIGS. One word is 30 bits, and one subframe corresponds to 10 words. Each word is composed of a 24-bit data portion and 6 bits for parity check. At the beginning of each subframe, a TLM (TeLeMetry) word and then a HOW (HandOver Word) are described. The TLM word includes a synchronization pattern, and the HOW includes GPS signal time information.

  The time in the GPS signal is managed in units of one week. The beginning of the week is 0:00 on every Sunday (24:00 on Saturday), and the time is expressed by the elapsed time (TOW (Time Of Week)). The HOW includes a number representing this elapsed time in 1.5 second units, and gives a clue that the receiver knows the current time. Each week is assigned a number (week number: WN (Week Number)), and the week starting at 00:00:00 on January 6, 1980 is set to week number 0. From this point, the week number is incremented by 1 every week. For example, the week number of the week starting on October 10, 2004 is 1292.

  The navigation data is divided and accommodated in the five subframes. Hereinafter, some items will be described, but the details can be understood by referring to GPS-ICD-200 or the like.

  With reference to FIGS. 5 to 9, navigation data information (mainly information relating to the present embodiment) will be briefly described.

  FIG. 5 shows the internal configuration of the HOW. As shown in FIG. 5, in the HOW described in all the subframes 1 to 5, the above TOW is described in the bit positions 1 to 17, and the bit positions 20 to 22 (the bit positions 50 to 50 of the subframe). 52) describes a subframe ID for identifying each subframe. The subframe ID is described in bit positions 20 to 22 of the HOW.

  FIG. 6 shows the configuration of subframe 1. As shown in FIG. 6, the subframe 1 of the navigation data contains a numerical value representing the state of the GPS satellite itself that is transmitting the navigation data and a clock correction coefficient. In subframe 1, following the first TLM word and HOW, the week number WN, ranging accuracy URA, and satellite health status SVhealth described above are described.

  Ranging accuracy URA is a rough standard of ranging accuracy when a pseudo-range (a distance between a GPS satellite and a receiver measured by adding an error due to advance of a receiver clock) is measured by the satellite. In the case of, it means that something is wrong. The satellite health state SVhealth is a code indicating the state of the satellite, and when it is other than 0, it indicates that there is some abnormality.

  The subframes 2 and 3 store the orbit information of each satellite (refer to GPS-ICD-200 for details). Such orbit information is called ephemeris, and the position of the GPS satellite at an arbitrary time can be calculated.

  The rough orbit information for all GPS satellites is called almanac (almanac data), and is stored in pages 2 to 5 and 7 to 10 of subframe 4 and pages 1 to 24 of subframe 5, for a total of 32 pages. Corresponds to the GPS satellite of the aircraft. The almanac data is included in the subframe of the GPS signal and is also stored in the storage unit 20 in the timepiece device 100 as a receiver. The almanac data stored in the storage unit 20 is updated with the received almanac data once every several months. FIG. 7 shows a configuration of a subframe including almanac data.

  FIG. 8 shows the configuration of subframe 4 of page 18. As shown in FIG. 8, the TLM word and HOW are described at the top of the subframe 4 of the page 18. Further, in the subframe 4 of the page 18, an SV ID (page ID) for identifying the page 18 is described in the bit positions 63 to 68. The ionosphere distributed at an altitude of 100 km or more has a function of delaying radio waves, and information for correcting the delay amount is described in subframe 4 (bit position 144) of page 18. The SV ID (page ID) is also described in another page of the subframe 4.

In subframe 4 of page 18, the current leap second Δt _LS , leap second update week WN _LSF , leap second update date DN, and updated leap second Δt _LSF are described in bit positions 241 to 278. Yes. The current leap second, leap second update week, leap second update date, and updated leap second are information necessary for leap second correction and are leap second correction data.

  FIG. 9 shows the configuration of subframe 5 with page numbers 1 to 24. As shown in FIG. 9, TLM word and HOW are described at the head of subframe 5. Also in the subframe 5, an SV ID (page ID) for identifying each page number of the subframe 5 is described in bit positions 63 to 68.

  Thus, the subframe ID can be acquired from the HOW by receiving the subframes 1 to 5 of the navigation data, and the page ID can be acquired from the SV ID by receiving the subframes 4 and 5 having a plurality of pages. is there. Further, leap second correction data can be acquired by receiving subframe 4 of page 18.

  Next, the operation of the timepiece device 100 according to the present embodiment will be described with reference to FIGS. FIG. 10 shows an outline of the first leap second correction process.

  As shown in FIG. 10, it takes 12.5 minutes to receive all the navigation data transmitted from the GPS satellite. Among all data, at time T1, each subframe is received and GPS measurement operation such as position measurement of the own apparatus is performed. At the end of the time T1, the clock device 100 is turned off to supply power to the GPS measurement portion in order to save power.

  However, leap second correction data is stored only in page 18 of subframe 4. In the first leap second correction process according to the present embodiment, since leap second correction is performed, for the time T2 at which leap second correction data can be received, the time from time T1 to time T2 is calculated, and after that calculation time. At time T2, at least page 18 of subframe 4 is received to obtain leap second correction data, and leap second correction is performed at the leap second correction timing using the leap second correction data.

  With reference to FIGS. 11 and 12, the first leap second correction process executed in the timepiece device 100 in the present embodiment will be described. FIG. 11 shows the flow of the first leap second correction process. FIG. 12A shows a flow of leap second correction data acquisition timing calculation processing. FIG. 12B shows a flow of leap second insertion timing calculation processing.

  In the timepiece device 100, for example, the timepiece 100 is read from the program area 191 of the ROM 19 triggered by the start of clock correction or the input of the execution instruction of the first leap second correction process from the user via the operation unit 18. The first leap second correction process executed in cooperation with the first leap second correction program developed in the program area 211 of the RAM 21 and the CPU 11 is executed.

  First, a GPS measurement operation is started (step S11). The GPS measurement operation is an operation for receiving navigation data from a GPS satellite for the time adjustment of the timepiece device 100, and is a part of the time adjustment operation for adjusting the time using the received navigation data. In the present embodiment, the time adjustment operation is a known operation, and the description of the time adjustment operation is omitted.

  Then, at least one GPS satellite among the receivable GPS satellites is captured, and navigation data is received from the captured GPS satellites via the antenna 17a and the GPS module 17 (step S12). The received navigation data includes at least time information for time correction (HOW, week number WN of subframe 1), page ID, subframe ID, and does not include subframe 4 of page 18. Shall.

  Then, time information is acquired from the navigation data received in step S12 and stored in the data area 212 of the RAM 21 (step S13). Then, the page number and subframe number are acquired from the page ID and subframe ID of the navigation data received in step S12, and stored in the data area 213 and data area 214 of the RAM 21, respectively (step S14). The page ID is included only in the subframes 4 and 5, as shown in FIGS. Further, the subframe ID is included in the HOW in each subframe as shown in FIG. The subframe number is a subframe ID or (subframe ID + 1).

  Then, the GPS measurement operation started from step S11 is ended (step S15). With the end of the GPS measurement operation, the power supply from the battery 16 to the parts related to reception of GPS measurements such as the GPS module is stopped.

  Then, leap second correction data acquisition timing calculation processing is executed (step S16). In step S <b> 16, as will be described later, leap second correction data acquisition timing T indicating the timing for receiving leap second correction data is calculated and stored in the data area 215 of the RAM 21.

  Then, the margin time is read out from the data area 203, and it is determined whether or not the internal time data of the clock count circuit 27 has reached the leap second correction data acquisition timing T-30 seconds (margin time) (step S17). . The 30 seconds is an example of a margin time that is set in advance in order to provide a margin for reception in order to reliably receive the subframe when the subframe 4 of the page 18 is received.

  If the leap second correction data acquisition timing T is not 30 seconds (step S17; NO), the process proceeds to step S17. When the value of the timer reaches the leap second correction data acquisition timing T-30 seconds (step S17; YES), the GPS measurement operation is started as in step S11 (step S18).

  Then, the GPS satellite acquisition and navigation data are received as in step S12 (step S19). The navigation data received in step S19 includes the data of subframe 4 of page 18. Then, leap second correction data (leap second update week, leap second update date, leap second number after update, etc.) is acquired from the data of subframe 4 on page 18 of the navigation data received in step S20. It is stored in the data area 216 (step S20).

  Then, the GPS measurement operation started from step S18 is ended (step S21).

  Then, leap second insertion timing calculation processing is executed (step S22). In the leap second insertion timing calculation process, as will be described later, a leap second insertion timing S indicating the timing for inserting (correcting) the leap second is calculated and stored in the data area 217 of the RAM 21.

  Then, the leap second insertion timing S stored in the data area 217 is read, and it is determined whether or not the leap second insertion timing S has been reached (step S23). Whether or not the leap second insertion timing S has come is determined, for example, by whether or not the date information of the internal time data of the clock count circuit 27 has reached the date corresponding to the leap second insertion timing S.

  When the leap second insertion timing S is reached (step S23; YES), the leap second correction data stored in the data area 216 is read and the internal clock count circuit 27 stores the leap second correction data based on the leap second correction data. The time data is corrected for leap seconds (step S24).

  Then, it is determined whether or not to end the first leap second correction process (step S25). In step S25, for example, the determination is made based on whether or not an instruction to end the first leap second correction process is input from the user via the operation unit 18. If the leap second insertion timing S is not reached (step S23; NO), the process proceeds to step S25.

  When the first leap second correction process is finished (step S25; YES), the first leap second correction process is finished. If the first leap second correction process is not terminated (step S25; NO), the leap second correction data acquisition timing T is set to leap second correction data acquisition timing T + 12.5 minutes (step S26), and the process proceeds to step S17. The By the loop through step S26, leap second correction data is received at an acquisition timing of every 12.5 minutes.

  With reference to Fig.12 (a), the leap second correction data acquisition timing calculation process of step S16 of a 1st leap second correction process is demonstrated in detail. As shown in FIG. 12A, after execution of step S15, time information, page number, and subframe number are read from the data area 212, data area 213, and data area 214 of the RAM 21 (step S161).

Then, the formula data is read from the data area 192 of the ROM 19, and the value dT is calculated by the following formula (1) of the formula data using the page number and subframe number read in step S161 (step S162). ).
dT = (18.8− (page number + subframe number × 0.2)) × 30 (1)
18.8 in the formula (1) represents the subframe 4 of the page 18 with a numerical value. Further, (page number + subframe number × 0.2) is a numerical representation of the page number and subframe number acquired by GPS measurement. Reference numeral 30 denotes a reception time of one frame (subframes 1 to 5).

  Then, it is determined whether or not the value dT calculated in step S162 is less than 60 seconds (step S163). When the value dT is less than 60 seconds (step S163; YES), the value dT is updated to the value dT + 12.5 minutes (step S164). Then, the time information + value dT read in step S161 is set as the leap second correction data acquisition timing T (step S165).

  When the value dT is 60 seconds or more (step S163; NO), the process proceeds to step S165. Then, the leap second correction data acquisition timing T calculated in step S165 is stored in the data area 215 of the RAM 21 (step S166), and the leap second correction data acquisition timing calculation processing ends. Then, the process proceeds to step S17.

  With reference to FIG.12 (b), the leap second insertion timing calculation process of step S22 of a 1st leap second correction process is demonstrated in detail. As shown in FIG. 12B, after execution of step S21, leap second correction data is read from the data area 216 of the RAM 21 (step S221).

Then, the formula data is read from the data area 192 of the ROM 19, and the leap second update week and leap second update date of the leap second correction data read in step S221 is used to obtain the following equation (2) of the equation data: The leap second insertion timing S is calculated (step S222).
S = base date + leap second update week x 7 + leap second update date (2)
However, the reference date is the day when the GPS week signal is 0 weeks. The leap second update week × 7 is the number of days obtained by multiplying the number of weeks in which leap seconds are updated by the number of days 7 of a week. The leap second update date is the number of days from the beginning of the week when the leap second is updated.

  Then, the leap second insertion timing S calculated in step S222 is stored in the data area 217 of the RAM 21 (step S223), and the leap second insertion timing calculation processing ends. Then, the process proceeds to step S23.

  As described above, according to the present embodiment, the timepiece device 100 calculates the leap second correction data acquisition timing T when the navigation data is received, and the internal time data reaches the leap second correction data acquisition timing T. Since the correction data is received, the leap second correction data can be reliably received and the leap second correction can be performed, and the power supply of the GPS module 17 can be stopped during the time when the leap second correction data is not received, so that the power consumption can be reduced.

  Moreover, since leap second insertion timing S is calculated and leap second correction is performed when the internal time data reaches leap second insertion timing S, leap seconds can be reliably corrected at an appropriate timing.

  Also, since leap second correction data is received every 12.5 minutes from the initial leap second correction data acquisition timing T (-30 seconds), any leap second correction data can be reliably acquired without leaking.

  Further, since the leap second correction data is received before the leap second correction data acquisition timing T, the leap second correction data can be received with a margin, and the leap second correction data can be acquired more reliably.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, as in the first embodiment, the timepiece device 100 is used, the description of the same configuration as in the first embodiment is omitted, and different portions are mainly described.

  As the device configuration of the present embodiment, the timepiece device 100 is used as in the first embodiment.

  Various types of information stored in the timepiece device 100 will be described with reference to FIG. FIG. 13A shows a storage area for storing information in the ROM 19 in the present embodiment. FIG. 13B shows a storage area for storing information in the storage unit 20. FIG. 13C shows a storage area for storing information in the RAM 21.

  As shown in FIG. 13A, the ROM 19 has a program area 193 and a data area 192. The program area 193 stores a second leap second correction program (data).

  As illustrated in FIG. 13B, the storage unit 20 includes data areas 201 to 204. The data area 204 stores a setting timing as a timing for performing a leap second correction before the leap second insertion timing S and in advance. In the present embodiment, the setting timing is information indicating the timing after 23:00 at the end of the month, but is not limited to this. The leap second is inserted at a certain timing such as UTC (Coordinated Universal Time) December 31, 23:59:60, and June 30, 23:59:60. May be information including at least the timing of the end of June and the end of December (the timing of passing a predetermined time (23:00, etc.)). It should be noted that since the data for announcing leap seconds is not determined exactly when it is updated on the GPS satellite side, leap second correction data may be received from the end of June and the end of December to several days before. preferable.

  As illustrated in FIG. 13C, the RAM 21 includes a program area 218 and data areas 212 to 217. In the program area 218, the second leap second correction program (data) is developed.

  Next, a second leap second correction process executed by the timepiece device 100 in the present embodiment will be described with reference to FIG. FIG. 14 shows the flow of the second leap second correction process.

  In the timepiece device 100, for example, it is read from the program area 193 of the ROM 19 triggered by the start of time correction or the input of the execution instruction of the second leap second correction process from the user via the operation unit 18. A second leap second correction process is executed in cooperation with the second leap second correction program developed in the program area 218 of the RAM 21 and the CPU 11.

  Steps S31 to S37 are the same as steps S11 to S17 of the first leap second correction process. Then, the setting timing is read from the data area 204 of the storage unit 20, and based on this setting timing, it is determined whether or not the internal time data of the clock counting circuit 27 is the timing after 23:00 at the end of the month. (Step S38). If the internal time data is not the timing after 23:00 at the end of the month (step S38; NO), the leap second correction data acquisition timing T is updated to the leap second correction data acquisition timing T + 12.5 minutes (step S39), and step S37. It is transferred to.

  When the internal time data is at a timing after 23:00 at the end of the month (step S38; YES), the process proceeds to step S40. Steps S40 to S46 are the same as steps S18 to S24 of the first leap second correction process. However, if the leap second insertion timing S is not reached (step S45; NO), the process proceeds to step S45. In addition, after the execution of step S46, the second leap second correction process ends.

  As described above, according to the present embodiment, the timepiece device 100 receives the leap second correction data at the leap second correction data acquisition timing and the set timing, so that the leap second correction data can be reliably obtained at a more appropriate timing. The leap second correction can be performed and the number of times the leap second correction data is received can be reduced, and the power consumption can be reduced.

  In particular, if the set timing is set to the minimum necessary timing at the end of June and December, the number of leap second corrections can be further reduced, and the power consumption can be further reduced.

  Also, if you work to receive leap second advance notice data, you can try again even if reception of leap second correction data fails, ensuring that the actual leap second is inserted. The probability of correcting leap seconds can be increased.

  The description in the above embodiment is an example of the timepiece device and leap second correction method according to the present invention, and the present invention is not limited to this.

  For example, in the present embodiment, the timepiece device 100 capable of correcting the time using a GPS signal is used, but the present invention is not limited to this. For example, the timepiece device 100 may be incorporated into a GPS receiver that performs position measurement.

  In the second embodiment, the navigation data including the subframe 4 of page 18 may be received and the leap second correction data may be received at the set timing. Information such as leap second correction data, leap second correction data acquisition timing, leap second correction timing, and the like stored in the RAM 21 may be appropriately stored in the storage unit 20.

  Further, in the first embodiment, 12.5 minutes is added to the leap second correction data acquisition timing T, the reception timing is repeatedly determined, and reception of leap second correction data is repeated. However, the present invention is not limited to this. For example, after step S17, a 12.5 minute timer is started, and after leap second correction data is received, leap second correction data is received at the timing when the timer becomes 0, and the next 12.5 minute timer is set. It is good also as repeating starting.

  In the first embodiment, the leap second correction data acquisition timing T is information indicating time, and by comparing with the internal time data of the time measuring unit 24, the leap second correction data acquisition timing T-30 seconds. However, the present invention is not limited to this. For example, the reception timing of leap second correction data may be determined by starting a timer when receiving navigation data and determining whether or not the timer value dT-30 seconds has elapsed.

  In addition, it is needless to say that the detailed configuration and detailed operation of each component of the timepiece device 100 in the above embodiment can be appropriately changed without departing from the gist of the present invention.

1 is a block diagram showing an internal configuration of a timepiece device 100 according to a first embodiment of the present invention. (A) is a figure which shows the storage area which memorize | stores information in ROM19 in 1st Embodiment. (B) is a diagram showing a storage area for storing information in the storage unit 20. (C) is a diagram showing a storage area for storing information in the RAM 21. It is a figure which shows the format of navigation data. It is a figure which shows schematic structure of a sub-frame. It is a figure which shows the internal structure of HOW. 2 is a diagram illustrating a configuration of a subframe 1. FIG. It is a figure which shows the structure of the sub-frame containing almanac data. FIG. 6 is a diagram showing a configuration of subframe 4 of page 18. It is a figure which shows the structure of the sub-frame 5 of page numbers 1-24. It is a figure which shows the outline | summary of a 1st leap second correction process. It is a flowchart which shows a 1st leap second correction process. (A) is a flowchart which shows a leap second correction data acquisition timing calculation process. (B) is a flowchart showing leap second insertion timing calculation processing. (A) is a figure which shows the storage area which memorize | stores information in ROM19 in 2nd Embodiment. (B) is a diagram showing a storage area for storing information in the storage unit 20. (C) is a diagram showing a storage area stored in the RAM 21. It is a flowchart which shows a 2nd leap second correction process.

Explanation of symbols

100 Clock device 11 CPU
12 Display Drive Circuit 13 Display Unit 14 Buzzer Circuit 15 Speaker 16 Battery 17 GPS Module 18 Operation Unit 19 ROM
20 storage unit 21 RAM
22 Illumination Drive Circuit 23 Illumination Unit 24 Timekeeping Unit 25 Oscillation Circuit 26 Dividing Circuit 27 Count Clock Circuit

Claims (12)

A timekeeping means that keeps the current time as internal time data,
Receiving means for receiving navigation data transmitted from a GPS satellite;
First acquisition means for acquiring each subframe and page identification information and time information from the navigation data received by the reception means;
Receiving time calculation for calculating the time until receiving leap second correction data included in the subframes after the subframe from the identification information and time information of the subframe and page acquired by the first acquisition unit Means,
The reception time calculating means includes
A reception timing value calculating means for calculating a reception timing value using each identification information of a subframe and a page;
Reception timing value determination means for determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and from the updated reception timing value and time information First setting means for setting a time until receiving leap second correction data;
If the reception timing value is not less than a predetermined time, the second setting means for setting the time until reception of leap second correction data from the reception timing value and time information,
Based on the time until receiving the leap second correction data calculated by the reception time calculation means, a reception timing determination means for determining whether or not the reception timing for receiving the leap second correction data is reached;
When it is determined by the reception timing determination means that it is time to receive the leap second correction data, the reception means receives the navigation data, and the reception data is included in the subframe included in the received navigation data. A second acquisition means for acquiring second correction data;
Leap second correction control means for correcting the leap second of the internal time data of the time measuring means based on the leap second correction data acquired by the second acquisition means;
A timepiece device comprising:   The reception timing determining means receives the leap second correction data at the time indicated by the internal time data of the time measuring means based on the time until the leap second correction data calculated by the reception time calculating means is received. The timepiece device according to claim 1, wherein it is determined whether or not reception timing has come.   The reception timing discriminating means is a reception timing for receiving the leap second correction data based on the time until reception of the leap second correction data calculated by the reception time calculation means. The timepiece device according to claim 1, wherein it is determined whether or not.   4. The reception timing determination unit determines whether or not a reception timing corresponding to a time before the reception of the leap second correction data is reached, according to any one of claims 1 to 3. The clock device described in 1. After the acquisition of the leap second correction data by the second acquisition means, the update means for updating the reception timing to acquire the leap second correction data to the reception timing to acquire the next leap second correction data,
The said reception timing discrimination means discriminate | determines whether it became the reception timing which should acquire the leap second correction data updated by the said update means, It is any one of Claim 1 to 4 characterized by the above-mentioned. Clock device. A timekeeping means that keeps the current time as internal time data,
Receiving means for receiving navigation data transmitted from a GPS satellite;
First acquisition means for acquiring each subframe and page identification information and time information from the navigation data received by the reception means;
Based on the identification information and time information of the subframe and page acquired by the first acquisition means, the leap second correction data acquisition timing of the leap second correction data included in the other subframe is acquired. Acquisition timing calculation means for calculating as timing;
The acquisition timing calculation means includes
A reception timing value calculating means for calculating a reception timing value using each identification information of a subframe and a page;
Reception timing value determination means for determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and the updated reception timing value and time information are obtained. A first setting means for setting the leap second correction data acquisition timing based on:
A second setting means for setting the leap second correction data acquisition timing based on the reception timing value and the time information when the reception timing value is not less than a predetermined time;
Immediately before reaching the leap second correction data acquisition timing calculated by the acquisition timing calculation means, the reception means receives the navigation data, and the leap second correction data included in the subframe in the received navigation data is received. A second acquisition means for acquiring;
Leap second correction control means for correcting leap seconds of the internal time data of the time measuring means based on the leap second correction data acquired by the second acquisition means;
A timepiece device comprising: A timekeeping means that keeps the current time as internal time data,
Receiving means for receiving navigation data transmitted from a GPS satellite;
First acquisition means for acquiring each subframe and page identification information and time information from the navigation data received by the reception means;
Receiving time calculation for calculating the time until receiving leap second correction data included in the subframes after the subframe from the identification information and time information of the subframe and page acquired by the first acquisition unit Means,
The reception time calculating means includes
A reception timing value calculating means for calculating a reception timing value using each identification information of a subframe and a page;
Reception timing value determination means for determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and from the updated reception timing value and time information First setting means for setting a time until receiving leap second correction data;
If the reception timing value is not less than a predetermined time, the second setting means for setting the time until reception of leap second correction data from the reception timing value and time information,
A setting timing discriminating means for discriminating whether or not the time indicated by the internal time data of the time measuring means has reached a setting timing for receiving preset leap second correction data;
When it is determined by the setting timing determining means that the setting timing for receiving the leap second correction data has been reached, the receiving means receives the navigation data and is included in the subframe in the received navigation data. A second acquisition means for acquiring leap second correction data;
Leap second correction control means for correcting the leap second of the internal time data of the time measuring means based on the leap second correction data acquired by the second acquisition means;
A timepiece device comprising:   The timepiece device according to claim 7, wherein the setting timing corresponds to a scheduled time when leap second correction is performed on the GPS satellite side, and includes a timing corresponding to at least the last day of June and December. Correction timing calculating means for calculating leap second correction timing based on leap second correction data acquired by the second acquisition means;
Correction timing determining means for determining whether or not the time indicated by the internal time data of the time measuring means has reached a correction timing for correcting leap seconds based on the correction timing calculated by the correction timing calculating means. ,
9. The leap second correction control means corrects leap seconds of the internal time data of the time measuring means when it is determined that the correction timing is reached. 9. Clock device. A first receiving step of receiving navigation data transmitted from a GPS satellite;
A first acquisition step of acquiring identification information and time information of each subframe and page from the navigation data received in the first reception step;
Receiving time calculation for calculating the time taken to receive leap second correction data included in subframes after the subframe from the identification information and time information of the subframe and page acquired in the first acquisition step. Process,
The reception time calculating step includes
A reception timing value calculating step of calculating a reception timing value using identification information of each subframe and page;
A reception timing value determination step of determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and from the updated reception timing value and time information A first setting step of setting a time until receiving leap second correction data;
If the reception timing value is not less than a predetermined time, a second setting step of setting a time until reception of leap second correction data from the reception timing value and time information,
A reception timing determination step for determining whether it is a reception timing for receiving the leap second correction data, based on the time until the leap second correction data calculated in the reception time calculation step is received;
A second reception step of receiving navigation data when it is determined that the timing for receiving the leap second correction data is reached in this reception timing determination step;
A second acquisition step of acquiring leap second correction data included in the subframe in the navigation data received in the second reception step;
Based on the leap second correction data acquired in the second acquisition step, the leap second correction control step of correcting the leap second of the internal time data of the time measuring means that measures the current time and holds it as internal time data;
A leap second correction method comprising: A first receiving step of receiving navigation data transmitted from a GPS satellite;
A first acquisition step of acquiring identification information and time information of each subframe and page from the navigation data received in the first reception step;
Based on the identification information and time information of each subframe and page acquired in the first acquisition step, the leap second correction data acquisition timing for acquiring leap second correction data included in other subframes is acquired. An acquisition timing calculation step to calculate as timing;
The acquisition timing calculation step includes
A reception timing value calculating step of calculating a reception timing value using identification information of each subframe and page;
A reception timing value determination step of determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and the updated reception timing value and time information are obtained. A first setting step for setting the leap second correction data acquisition timing based on:
A second setting step for setting a leap second correction data acquisition timing based on the reception timing value and the time information when the reception timing value is not less than a predetermined time; and
A second reception step of receiving navigation data immediately before reaching the leap second correction data acquisition timing calculated in the acquisition timing calculation step;
A second acquisition step of acquiring leap second correction data included in the subframe in the navigation data received in the second reception step;
Based on the leap second correction data acquired in the second acquisition step, the leap second correction control step of correcting the leap second of the internal time data of the clock means that measures the current time and holds it as internal time data;
A leap second correction method comprising: A first receiving step of receiving navigation data transmitted from a GPS satellite;
A first acquisition step of acquiring the identification information and time information of each subframe and page from the navigation data received by the first reception step;
Receiving time calculation for calculating the time from reception of leap second correction data included in subframes subsequent to the subframe from the identification information and time information of the subframe and page acquired in the first acquisition step. Process,
The reception time calculating step includes
A reception timing value calculating step of calculating a reception timing value using identification information of each subframe and page;
A reception timing value determination step of determining whether or not the reception timing value is less than a predetermined time;
When the reception timing value is less than a predetermined time, the reception timing value is updated by adding the time necessary to receive all the frames of the navigation data to the reception timing value, and from the updated reception timing value and time information A first setting step of setting a time until receiving leap second correction data;
If the reception timing value is not less than a predetermined time, a second setting step of setting a time until reception of leap second correction data from the reception timing value and time information,
A setting timing determination step for determining whether or not the time indicated by the internal time data of the time measuring means for measuring the current time and holding it as internal time data has reached a setting timing for receiving preset leap second correction data;
A second receiving step for receiving navigation data when it is determined that the setting timing for receiving the leap second correction data is reached in the setting timing determining step;
A second acquisition step of acquiring leap second correction data included in the subframe in the navigation data received in the second reception step;
A leap second correction control step of correcting the leap second of the internal time data of the time measuring means based on the leap second correction data acquired by the second acquisition step;
A leap second correction method comprising:

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