JP2019027914A - Radio-controlled timepiece - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress an increase in power consumption. SOLUTION: This is a radio clock 100 having a receiving circuit 31 for executing a receiving operation of a satellite signal including a plurality of pages transmitted in chronological order, and an environment determination unit 47a for determining whether or not to execute the receiving operation. , The acquisition means 47b for acquiring the internal time when it is determined to execute the reception operation, the signal determination means 47c for determining the page corresponding to the internal time, and the weekly time based on the corresponding page. It has a selection means 47d for selecting whether or not to cause the reception circuit 31 to execute a reception operation for receiving TOW or a reception operation for receiving LS information. [Selection diagram] Fig. 3

Description

  The present invention relates to a radio timepiece.

  Patent Document 1 discloses a radio timepiece that corrects an internal time based on a weekly time TOW (Time Of Week) included in a satellite signal transmitted from a GPS (Global Positioning System) satellite. The weekly time TOW indicates the elapsed seconds from 0:00 on the most recent Sunday. The satellite signal includes information on future leap second (LS), and the information is updated irregularly. Note that leap second adjusts the difference between the time output from the GPS satellite atomic clock and UTC (Universal Time, Coordinated).

JP 2011-208948 A

  Information about future leap seconds (hereinafter also referred to as LS information) is included only once in 25 times (pages 1 to 25) of the subframe 4 of the satellite signal. Specifically, the LS information is included only in the subframe 4 of the page 18. Since one page includes a signal for 30 seconds, the LS information is transmitted only once every 12.5 minutes. For this reason, if the reception operation is started at a timing that is unnecessarily earlier than the timing at which the subframe including the LS information is transmitted, it may take a long time to receive the LS information, which may increase power consumption. is there.

  The present invention has been made in view of such circumstances, and an object thereof is to suppress an increase in power consumption in a radio timepiece that receives information on future leap seconds.

  The invention disclosed in the present application in order to solve the above problems has various aspects, and the outline of typical ones of these aspects is as follows.

  (1) A radio timepiece having reception means for executing a reception operation of a satellite signal including a plurality of signal units transmitted in time order, the detection means detecting information related to the reception environment of the radio timepiece, and the reception environment An environment determination unit that determines whether or not the environment condition of the reception operation is satisfied based on the information about the reception operation, and the radio timepiece when the environment determination unit determines that the environment condition of the reception operation is satisfied The satellite based on the acquisition unit for acquiring the internal time to be held, the signal determination unit for determining the signal unit corresponding to the internal time acquired by the acquisition unit, and the signal unit determined by the signal determination unit The receiving operation for receiving information on the current time included in the signal, or the receiving operation for receiving information on a future leap second included in the satellite signal Radio clock having a selection means for selecting whether or not to execute the receiving means

  (2) In (1), the selection means is based on the signal unit determined by the signal determination means and the number of days that have elapsed since the reception operation for receiving information related to the current time was executed last time. A radio timepiece that selects whether or not to cause the receiving means to execute the receiving operation for receiving information related to the current time.

  (3) In (1) or (2), the selection unit has executed the reception operation for receiving the information on the signal unit determined by the signal determination unit and the future leap second last time. A radio-controlled timepiece that selects whether or not to cause the reception means to execute the reception operation for receiving information on the future leap second based on the number of days elapsed.

  (4) In any one of (1) to (3), the selecting means is based on whether the signal unit determined by the signal determining means and information on the future leap second have been received. A radio-controlled timepiece that selects whether or not to cause the receiving means to execute the receiving operation for receiving information about future leap seconds.

  (5) In any one of (1) to (4), the selection unit is based on whether the signal unit determined by the signal determination unit is within a receivable period of information on the future leap second. A radio-controlled timepiece that selects whether or not to cause the receiving means to execute the receiving operation for receiving information on the future leap second.

  (6) The radio timepiece according to any one of (1) to (5), wherein the signal unit is a page of the satellite signal.

  (7) The radio timepiece according to any one of (1) to (5), wherein the signal unit is a subframe of the satellite signal.

  (8) In (1), the environment determination means relates to the current time when the reception operation for receiving the information related to the future leap second has been performed for the first time or more after the previous execution. A radio-controlled timepiece that determines whether or not an environmental condition of the reception operation is satisfied only in any case where the second number of days or more has elapsed since the reception operation for receiving information was previously performed.

  According to the above aspects (1) to (8) of the present invention, an increase in power consumption can be suppressed.

It is a top view which shows the radio timepiece concerning this embodiment. It is sectional drawing by the AA line of FIG. It is a figure which shows the circuit structure and system structure of the radio timepiece which concern on this embodiment. It is a figure which shows the structure of 1 sub-frame in the satellite signal which a GPS satellite transmits. It is a figure explaining the time information reception operation in this embodiment. It is a figure explaining the leap second information reception operation | movement in this embodiment. It is a figure explaining the receiving operation selected when the page of the satellite signal corresponding to the internal time when it is determined that the environmental condition of the receiving operation is satisfied is any one of pages 1 to 15 and 18 to 25. . It is a figure explaining the receiving operation selected when the page of the satellite signal corresponding to the internal time when it is determined that the environmental condition of the receiving operation is satisfied is page 16 or 17. It is a figure which shows the receiving operation selected in the case of the conditions 1 shown in FIG.7 and FIG.8. It is a figure which shows the receiving operation selected in the case of the conditions 2 shown in FIG.7 and FIG.8. FIG. 9 is a diagram showing a reception operation selected in the case of conditions 3, 5, and 7 shown in FIGS. 7 and 8. FIG. 9 is a diagram illustrating a reception operation selected in the case of conditions 4, 6, and 8 illustrated in FIGS. 7 and 8. It is a flowchart which shows operation | movement of the control part in this embodiment. It is a flowchart which shows operation | movement of the control part in the 1st modification of this embodiment. It is a flowchart which shows operation | movement of the control part in the 2nd modification of this embodiment.

  Hereinafter, an embodiment of the present invention (hereinafter referred to as the present embodiment) will be described in detail with reference to the drawings.

  FIG. 1 is a plan view showing a radio timepiece according to the present embodiment. FIG. 1 shows a case 1 that is an exterior (watch case) of the radio-controlled timepiece 100, a dial 2 disposed in the case 1, and an hour hand 3, a minute hand 4, and a second hand 5 that are hands indicating time. Further, a crown 6 and buttons 7 are arranged on the side surface of the trunk 1 on the 3 o'clock side for the user to perform various operations. A band fixing portion 8 for fixing the band extends from the side surface of the trunk 1 on the 12 o'clock side and the 6 o'clock side.

  The design of the radio timepiece 100 shown in FIG. 1 is an example. In addition to those shown here, for example, the barrel 1 may be square instead of round, and the presence / absence, number, and arrangement of the crown 6 and the button 7 are arbitrary. Further, in the present embodiment, the hands are three hands of the hour hand 3, the minute hand 4, and the second hand 5, but the present invention is not limited to this, and even if the second hand 5 is omitted, the day of the week, the time zone or the presence / absence of summer time, the radio wave The reception status, remaining battery level, pointers for various displays, date display, and the like may be added.

  In this embodiment, the radio-controlled timepiece 100 has a function of receiving a satellite signal transmitted from a GPS (Global Positioning System) satellite and correcting the internal time based on information on the date and time included in the satellite signal. This will be explained using. However, it is not limited to a wristwatch, and may be another wearable terminal having a clock function. The internal time is time information (including the current time and date) held by a clock circuit inside the radio timepiece 100.

  2 is a cross-sectional view taken along line AA in FIG. A windshield 9 is attached to the case 1 so as to cover the dial 2 of the radio timepiece 100, and a back cover 10 is attached to the case 1 on the opposite side of the windshield 9. The material of the windshield 9 is a transparent material such as glass, and is nonmagnetic and nonconductive. Moreover, although the material of the trunk | drum 1 and the back cover 10 is not specifically limited, In this embodiment, it is a metal. In the present embodiment, hereinafter, the direction in which the windshield 9 of the radio timepiece 100 is disposed (upward direction in FIG. 2) is referred to as the windshield side, and the direction in which the back cover 10 is disposed (downward direction in FIG. 2) is referred to as the back cover side. .

  A solar cell (photovoltaic panel) 11 is disposed on the back cover side of the dial plate 2, and power is generated by light incident from the windshield side. Therefore, the dial 2 is preferably formed of a material that transmits light to some extent. In the present embodiment, the dial 2 is fixed to the base member 12 so as to sandwich the solar cell 11.

  The base member 12 is made of a nonmagnetic and nonconductive material such as a synthetic resin, and supports various members such as the patch antenna 14 and a gear mechanism 25 for driving the pointer. The patch antenna 14 is provided with a feed pin 14b so as to penetrate the thickness direction thereof, and the windshield side surface serves as a reception surface 14a for receiving radio waves from the satellite.

  A circuit board 24 is disposed on the back cover side of the base member 12, and a battery 26 is disposed on the back cover side. In the present embodiment, the battery 26 is a rechargeable secondary battery, and uses a button-type lithium ion secondary battery. And the electric power generated by the solar cell 11 is accumulated. A motor 23 that is a drive source of the gear mechanism 25 is also attached to the circuit board 24. The shape of the battery 26 is not limited to the button type, and is arbitrary. Further, a secondary battery other than the lithium ion secondary battery, for example, a lithium ion capacitor or a nickel metal hydride battery may be used.

  Here, as shown in FIG. 2, the receiving surface 14 a of the patch antenna 14 is provided in parallel with the light receiving surface of the solar cell 11, and all face the windshield side. Further, as shown in FIG. 1, the solar cell 11 has a substantially circular shape, and a part of the outer periphery thereof is cut into a rectangular shape. And the patch antenna 14 is arrange | positioned at this part. For this reason, the receiving surface 14 a of the patch antenna 14 and the light receiving surface of the solar cell 11 are both directly opposed to the back surface of the dial 2. In the present embodiment, the power generation amount of the solar cell 11 is set as the light reception amount of the radio timepiece 100. The situation where strong light strikes the dial 2 is likely to be in an environment suitable for receiving satellite signals because the patch antenna 14 faces the satellite, such as outdoors during the day or near the window.

  FIG. 3 is a diagram illustrating a circuit configuration and a system configuration of the radio timepiece according to the present embodiment. The circuit elements shown in FIG. 3 are mainly arranged on the circuit board 24. The satellite signal received by the patch antenna 14 is converted into a baseband signal by the high frequency circuit 46, and information related to time, specifically, information indicating time and date is extracted by the decoder circuit 53 and received by the control unit 47. Passed. The high frequency circuit 46 and the decoder circuit 53 constitute a receiving circuit (receiving means) 31. The control unit 47 is a microcomputer incorporating a driver of the motor 23, volatile and nonvolatile memory, a clock circuit, various AD converters, and the like, and various controls are executed according to programs stored in the nonvolatile memory. Here, date correction information is stored in the volatile memory built in the control unit 47. The date / time correction information is extracted from the satellite signal, and includes information on weekly time TOW described later, information on the current leap second, and information on the future leap second.

  Further, the solar cell 11 is connected to the battery 26 via the switch 29, and is generated by the solar cell 11 in a state in which the switch 29 connects the solar cell 11 and the battery 26 according to an instruction from the control unit 47. The accumulated power is stored in the battery 26. Then, power is supplied from the battery 26 to the high frequency circuit 46, the decoder circuit 53, and the control unit 47.

  In addition, the solar cell 11 is also connected to the power generation amount detection unit 30 via the switch 29, and in a state in which the switch 29 causes the solar cell 11 and the power generation amount detection unit 30 to conduct in accordance with an instruction from the control unit 47, The current generated by the solar cell 11 flows to the power generation amount detection unit 30. The power generation amount detection unit 30 converts this current into a voltage, further converts this voltage into a digital value, and supplies it to the control unit 47.

  The switch 56 is a switch for switching on / off the power supply to the reception circuit 31, that is, the high frequency circuit 46 and the decoder circuit 53, and is controlled by the control unit 47. Since the high-frequency circuit 46 and the decoder circuit 53 operating at a high frequency consume a large amount of power, the control unit 47 turns on the switch 56 only when receiving a satellite signal, and turns on the receiving circuit 31, that is, the high-frequency circuit 46 and the decoder circuit 53. In other cases, the switch 56 is turned off to reduce power consumption.

  Here, satellite signals (navigation data) transmitted by GPS satellites used for date correction of the radio timepiece 100 will be described. FIG. 4 is a diagram showing the configuration of one subframe in a satellite signal transmitted by a GPS satellite.

  GPS satellites repeatedly transmit satellite signals in a time sequence, with a total of 25 frames (pages) as one set. Each frame includes a signal for 30 seconds, and the GPS satellite transmits a signal of 25 frames in a cycle of 12.5 minutes. Further, each frame is composed of five subframes SF. Since one frame is 30 seconds, one subframe SF corresponds to a signal for 6 seconds. One subframe SF includes information of 300 bits as a whole. Furthermore, since one subframe SF is composed of 10 words and one subframe is 6 seconds, one word corresponds to a signal for 0.6 seconds.

  The head word of each subframe SF is called a TLM (TeLeMetry word), and the TLM includes a code indicating the head of each subframe SF and information on the ground control station. The leading portion of the TLM (that is, the leading portion of the entire subframe SF) includes a preamble indicating the start position of the subframe SF.

  The second word of each subframe SF is called HOW (HandOver Word), and the top part of the HOW is related to the GPS time starting from the beginning of the week (Sunday 0:00 am), that is, the current time. The information includes weekly time TOW (Time Of Week) as information. The information following the HOW differs for each subframe SF, and the subframe SF1 includes a week number WN (Week Number) following the HOW. The week number WN is information indicating the week number to which the time represented by the weekly time TOW belongs, and is counted up once a week and every Sunday at 0:00 am.

  The subframe SF2 and the subframe SF3 include the orbit information of each GPS satellite called ephemeris following the HOW, and the subframes SF4 and SF5 are the approximate orbits of all GPS satellites called the almanac following the HOW. Information is included, but detailed description thereof is omitted.

  Further, returning to FIG. 3, the description will be continued. The radio timepiece 100 receives satellite signals from one or more GPS satellites. Then, the control unit 47 stores the information of the weekly time TOW extracted from the received satellite signal in the built-in volatile memory, and corrects the internal time based on the stored information of the weekly time TOW. The motor 23 is driven based on the internal time. The rotational power generated by the motor 23 is transmitted to the hands (hour hand 3, minute hand 4 and second hand 5) through the train wheel, and the time is displayed.

  Further, as information for correcting the internal time, there is information on the current leap second. Leap second adjusts the time difference between the time output from the atomic clock of the GPS satellite and UTC (Universal Time, Coordinated). The control unit 47 stores information on the current leap second extracted from the satellite signal in advance in a built-in volatile memory, and corrects the internal time based on the stored information on the current leap second.

  In addition, as information for correcting the internal time, there is information about future leap seconds (hereinafter also referred to as LS information). The LS information is information including information on a leap second update scheduled date and time when the next leap second correction is performed, information on a correction amount in the next leap second correction, and the like. The control unit 47 stores the LS information extracted from the satellite signal in the built-in volatile memory, and corrects the internal time to the leap second update scheduled date and time based on the stored LS information. That is, the control unit 47 adds the internal time to the scheduled leap second update date and time based on the information about the future leap second acquired by the leap second update scheduled date and time in addition to the weekly time TOW and the current leap second information. Correct it. The leap second update scheduled date is, for example, the end of June or the end of December. Moreover, although LS information is updated irregularly, for example, it is included in the satellite signal transmitted from the GPS satellite only for one month before the leap second update scheduled date. Hereinafter, a period of one month before the leap second update scheduled date, that is, a period in which the LS information is included in the satellite signal and transmitted is referred to as an LS receivable period.

  If the radio timepiece 100 is in an environment that is not suitable for receiving satellite signals, such as indoors, it is highly possible that the satellite signals cannot be received even if the reception operation is executed. In such an environment, if the reception operation is executed, power is unnecessarily consumed. Therefore, in this embodiment, a reception environment check is performed to determine whether or not the radio timepiece 100 is in an environment suitable for the reception environment, and it is determined that the radio timepiece 100 is in an environment suitable for the reception environment. In other words, the reception operation is executed when the environmental condition of the reception operation is satisfied.

  The control unit 47 causes the reception circuit 31 to perform a satellite signal reception operation based on the detection result of the power generation amount detection unit 30. Specifically, whether or not the detection value (power generation amount) detected by the power generation amount detection unit 30 is equal to or greater than a predetermined threshold is determined at a predetermined interval, and when a detection value equal to or greater than the predetermined threshold is detected, The reception circuit 31 is caused to execute a satellite signal reception operation. This is because if the detection value detected by the power generation amount detection unit 30 is equal to or greater than a predetermined threshold, it is highly likely that the radio timepiece 100 is in an environment suitable for reception such as outdoors or near a window.

  With reference to FIG. 5, the time information receiving operation in the present embodiment will be described. FIG. 5 is a diagram for explaining the time information reception operation in the present embodiment. Here, the time information receiving operation refers to a receiving operation for receiving the weekly time TOW. In FIG. 5, the timing at which the reception environment check by the control unit 47 is performed is indicated by an arrow. Further, “OK” indicates that the detected value detected by the power generation amount detection unit 30 is equal to or greater than the predetermined threshold, and “NG” indicates that the detected value is less than the predetermined threshold. The same applies to FIG. 6 described later.

  FIG. 5 shows an example in which the environmental condition is satisfied when the “OK” determination is made twice in succession, and then the time information reception operation is continuously executed for 6 seconds. When “OK” determination is made twice consecutively, the controller 47 switches the switch 56 shown in FIG. 3 to the ON state. Then, the receiving circuit 31 is activated and receives a satellite signal. That is, the time information receiving operation for receiving the weekly time TOW is executed.

  As described above, the weekly time TOW is included in all the subframes SF. Therefore, even if the time information reception operation is started at any timing, the weekly time TOW can be acquired by continuing the reception operation for at least 6 seconds. In the example shown in FIG. 5, the weekly time TOW included in the subframe SF3 of page 2 is acquired. The subframe SF including the acquired weekly time TOW is arbitrary. That is, the time information reception operation may be performed at the timing of acquiring the weekly time TOW included in any of the subframes SF1 to SF5. For example, in the example shown in FIG. 5, in the reception environment check performed at the timing of the subframe SF4 of page 1 and the timing after 10 seconds (the timing of the top portion of the subframe SF1 of page 2), “OK” When the determination is made, the time information reception operation may be performed at a timing at which the weekly time TOW included in the subframe SF2 of page 2 can be acquired. In addition, FIG. 5 shows an example in which the reception environment check is performed at intervals of 10 seconds, but is not limited to this, and it may be longer or shorter than the intervals of 10 seconds. For example, when the detection interval of the reception environment check is set to 10 seconds, the driving timing of the minute hand 4 may be set to one step every 10 seconds. Thus, by matching the detection interval of the reception environment check with the interval for driving the pointer, the start timing of the control unit 47 (microcomputer) can be made the same. As a result, the frequency with which the control unit 47 is activated can be reduced, and the power consumption can be reduced.

  With reference to FIG. 6, the leap second information receiving operation in the present embodiment will be described. FIG. 6 is a diagram for explaining the leap second information receiving operation in the present embodiment.

  The LS information is included only once in 25 times (pages 1 to 25) of the satellite signal subframe SF4. Specifically, the LS information is included only in the subframe SF4 of the page 18. Since each of the subframes SF1 to SF5 is transmitted over 6 seconds, the LS information is transmitted once every 12.5 minutes. Note that the LS information is included after 4 to 5 seconds have elapsed from the TLM of the subframe SF4. In the radio-controlled timepiece 100, the LS information is acquired from the GPS satellite and combined with the week number WN information to adjust the time difference between the time output from the GPS satellite atomic clock and UTC (Universal Time, Coordinated). Can do. That is, in order to correct the leap second correctly based on the LS information, it is also necessary to acquire the week number WN included in the subframe SF1 of the page 18. In FIG. 6, the environment check is performed at 10-second intervals, and after the “OK” determination is made twice in succession, the leap second information reception operation is executed from five subframes before the subframe SF including the LS information. An example of starting is shown. Specifically, an example in which the leap second information reception operation is started from the top of the subframe SF4 of page 17 and the leap second information reception operation is continuously executed for 36 seconds until the end of the subframe SF5 of page 18 is shown. Note that the week number WN can be held inside the radio-controlled timepiece 100. In this case, at least the subframe SF4 of the page 18 may be received. In that case, it is only necessary to start the reception operation immediately before the TLM of the subframe SF4, and the execution time of the leap second information reception operation can be shortened and the power consumption can be suppressed. As described above, the weekly time TOW is included in all the subframes SF. Therefore, when the leap second information receiving operation is performed, the weekly time TOW can also be acquired.

  Here, as described above, since the LS information is transmitted only once every 12.5 minutes, the timing suitable for starting execution of the leap second information reception operation is limited, and other than the suitable timing. If the execution of the leap second information reception operation is started at the timing, the execution time of the reception operation becomes long and the power consumption increases. For example, when the execution of the leap second information reception operation is started at the timing of the subframe SF1 of the page 10, it is necessary to continue the reception operation from the page 10 to the subframe SF4 of the page 18 in order to receive the LS information. It takes about 270 seconds (30 seconds × 9 frames) to execute the reception operation. In addition, for example, when it is determined that the environmental condition of the reception operation is satisfied at the timing of the subframe SF1 of page 10, the reception operation is not started immediately, but the execution can be started after waiting for page 17 However, in this case, there is a possibility that the environmental condition is not satisfied when the reception operation is executed. If the environmental conditions are not satisfied when the reception operation is performed, there is a high possibility that the satellite signal reception will fail even if the reception operation is performed. If reception fails even though the reception operation is executed, power consumption is unnecessarily consumed.

  Therefore, in the present embodiment, the time information reception operation or leap second information reception operation is performed based on the page (signal unit) of the satellite signal corresponding to the internal time when it is determined that the environmental condition of the reception operation is satisfied. A configuration for selecting whether or not to execute either one is adopted. Hereinafter, a specific description will be given with reference to FIGS. 3 and 7 to 12.

  FIG. 7 illustrates the reception operation selected when the page of the satellite signal corresponding to the internal time when it is determined that the environmental condition of the reception operation is satisfied is any of pages 1 to 15 and 18 to 25. It is a figure to do. FIG. 8 is a diagram for explaining the reception operation selected when the page of the satellite signal corresponding to the internal time when it is determined that the environmental condition of the reception operation is satisfied is page 16 or 17. FIG. 9 is a diagram illustrating a reception operation selected in the case of the condition 1 illustrated in FIGS. 7 and 8. FIG. 10 is a diagram illustrating a reception operation selected in the case of the condition 2 illustrated in FIGS. 7 and 8. FIG. 11 is a diagram showing a reception operation selected in the case of conditions 3, 5, and 7 shown in FIGS. FIG. 12 is a diagram showing a reception operation selected in the case of conditions 4, 6, and 8 shown in FIGS.

  As shown in FIG. 3, the control unit 47 includes an environment determination unit 47a, an acquisition unit 47b, a signal determination unit 47c, and a selection unit 47d.

  The environment determination unit 47a determines whether or not the environmental condition of the satellite signal reception operation is satisfied based on the detection value detected by the power generation amount detection unit 30. In the present embodiment, as described above with reference to FIGS. 5 and 6, when the power generation amount detection unit 30 detects a detection value equal to or greater than a predetermined threshold value twice in succession (“OK” twice in succession). When the determination is made), the environment determination unit 47a determines that the environmental condition of the satellite signal reception operation is satisfied. Note that the environmental conditions shown in FIGS. 5 and 6 are examples, and the present invention is not limited to this. For example, the environmental condition may be satisfied when the “OK” determination is made once, or the detection is performed five times. The environmental condition may be satisfied when the “OK” determination is made three times or more.

  The acquisition unit 47b acquires the internal time held by the radio timepiece 100 when the environment determination unit 47a determines that the environmental condition of the satellite signal reception operation is satisfied. In the present embodiment, when it is determined that the environmental condition of the satellite signal reception operation is satisfied, “OK” is determined for the second time when the environment determination unit 47a determines that “OK” determination is performed twice consecutively. Is the timing when the determination is made.

  The signal determination unit 47c determines the page of the satellite signal corresponding to the internal time acquired by the acquisition unit 47b. For example, in the example shown in FIG. 5, page 2 corresponds to the page corresponding to the internal time when it is determined that the environmental condition of the satellite signal reception operation is satisfied, and in the example shown in FIG. 6, Page 17 corresponds to the page corresponding to the internal time when it is determined that the environmental condition of the satellite signal reception operation is satisfied.

  Based on the page determined by the signal determination unit 47c, the selection unit 47d performs either the time information reception operation for receiving the weekly time TOW or the leap second information reception operation for receiving LS information in the reception circuit 31. Select whether to execute or not.

  As described above, the LS information is included in the subframe SF4 of the page 18. Therefore, in this embodiment, in order to suppress an increase in the execution time of the reception operation, the leap second information reception operation has a page corresponding to the internal time when it is determined that the environmental condition of the reception operation is satisfied. The selection is made only in the case of page 16 or page 17 immediately before the subframe SF4 of page 18. On that basis, it is configured to select which reception operation is to be executed or not to be executed based on each determination element described later.

  In this embodiment, as shown in FIG. 7 and FIG. 8, whether it is within the LS receivable period (one month before the leap second update scheduled date), whether LS information has been received, leap second information receiving operation The number of days elapsed since the previous execution (LS in the figure: elapsed days) and the number of days elapsed since the time information reception operation was last executed (TOW: elapsed days in the figure) This is used as a determination element for selecting whether to execute or not to execute.

  The LS information is included in the satellite signal transmitted from the GPS satellite only for one month before the leap second update scheduled date. The leap second update scheduled date is the end of June or the end of December. That is, the period when the LS information can be received is from June 1 to the end of June, and from December 1 to the end of December. Therefore, in other periods (January to May, July to November), accurate LS information may not be acquired even if the leap second information reception operation is executed. Therefore, in the present embodiment, it is determined which reception operation is to be executed or not to be executed based on whether it is within the LS receivable period or outside the LS receivable period. The LS receivable period is generally in June or December as described above, but is only an example, and this period can be changed irregularly.

  When the LS information is received once, the internal time is corrected on the leap second update scheduled date based on the LS information. Therefore, if the LS information has already been received, it is not necessary to receive it thereafter. Therefore, in the present embodiment, it is determined which reception operation is to be executed or not to be executed depending on whether the LS information has been received or not.

  In addition, if leap second information reception operation is executed at a high frequency, the power consumption increases. Therefore, after the previous leap second information receiving operation is executed, the next leap second information receiving operation may be executed after a certain period of time. In the present embodiment, whether or not to execute the leap second information reception operation is determined based on whether or not three days (the first number of days) have elapsed since the previous leap second information reception operation was performed.

  Further, if the time information reception operation is executed at a high frequency, the power consumption increases. Therefore, it is preferable to execute the next time information reception operation after a certain period of time has passed after the previous time information reception operation is executed. The weekly time TOW is not limited in the receivable time unlike the LS information. Therefore, the execution frequency of the time information reception operation may be set lower than the execution frequency of the leap second information reception operation. Thereby, excessive power consumption can be suppressed. In the present embodiment, whether or not to execute the time information reception operation is determined based on whether or not six days (second number) have elapsed since the previous time information reception operation was executed. This is merely an example, and the number of days that will be a criterion for determining which reception operation is to be performed may be appropriately changed. The same applies to the leap second information receiving operation described above.

  Note that the number of days elapsed since the previous execution of the reception operation may be performed using a counter (not shown) built in the radio clock 100. In addition, the radio timepiece 100 may include a counter that counts the number of days that have elapsed since the previous time information reception operation was performed, and a counter that counts the number of days that have elapsed since the last execution of the leap second information reception operation. . For example, these counters may be incremented by 1 at 6 am every day and set to zero when a reception operation is performed.

  In addition, it may be set to increase the execution frequency of the leap second information receiving operation as the number of remaining days until the leap second update scheduled date decreases. For example, if the leap second information is scheduled to be updated within 2 weeks, it is determined whether the leap second information reception operation is executed depending on whether the leap second information reception operation was last performed or whether two days or more have elapsed. Good. By increasing the execution frequency, it is possible to improve the accuracy with which LS information can be received by the leap second update scheduled date. If the LS information cannot be acquired before the leap second update scheduled date, the user manually adjusts the time of the radio clock 100 so that the radio clock 100 displays the accurate time when the leap second correction is made in the future. Necessity arises.

  Hereinafter, referring to FIG. 7 and FIG. 9 to FIG. 12, the page of the satellite signal corresponding to the internal time when it is determined that the environmental condition of the receiving operation is satisfied is any of pages 1 to 15 and 18 to 25. The receiving operation selected in such a case will be specifically described.

  As shown in the condition 1 of FIG. 7, it is within the LS receivable period, the LS information has not been received, and three or more days have passed since the last leap second information receiving operation was performed. When six days or more have elapsed since the execution of the reception operation, the selection unit 47d selects the reception circuit 31 to execute the time information reception operation for receiving the weekly time TOW (see FIG. 9). .

  As shown in condition 2 of FIG. 7, the LS information is within the LS receivable period, the LS information has not been received, and three or more days have passed since the last leap second information receiving operation was performed. When the number of days elapsed since the execution of the reception operation is less than 6 days, the selection unit 47d selects that the reception circuit 31 does not execute the reception operation (see FIG. 10).

  As shown in condition 3 in FIG. 7, the LS information is within the LS receivable period, the LS information has not been received, and the number of days elapsed since the last leap second information reception operation is less than 3 days. When six days or more have elapsed since the execution of the time information reception operation, the selection unit 47d selects the reception circuit 31 to execute the time information reception operation for receiving the weekly time TOW (FIG. 11). reference).

  As shown in the condition 4 in FIG. 7, the LS information is within the LS receivable period, the LS information has not been received, and the number of days elapsed since the last leap second information reception operation is less than 3 days. When the number of days that have elapsed since the time information reception operation is performed is less than six days, the selection unit 47d selects that the reception circuit 31 does not perform the reception operation (see FIG. 12).

  As shown in the condition 5 of FIG. 7, when the LS information has been received within the LS receivable period and six days or more have elapsed since the previous time information reception operation was performed, the selection unit 47d Then, it is selected that the reception circuit 31 is to execute the time information reception operation for receiving the weekly time TOW (see FIG. 11).

  As shown in condition 6 of FIG. 7, it is selected when it is within the LS receivable period, the LS information has been received, and the elapsed time is less than 6 days since the previous time information reception operation was executed. The unit 47d selects not to cause the reception circuit 31 to perform the reception operation (see FIG. 12).

  As shown in condition 7 of FIG. 7, when it is outside the LS receivable period and six days or more have elapsed since the previous time information reception operation was performed, the selection unit 47d receives the weekly time TOW. Therefore, it is selected that the receiving circuit 31 performs the time information receiving operation for the purpose (see FIG. 11).

  As shown in the condition 8 in FIG. 7, when it is outside the LS receivable period and the number of days elapsed since the previous time information reception operation is performed is less than 6 days, the selection unit 47d causes the reception circuit 31 to perform the reception operation. Is selected not to be executed (see FIG. 12).

  Next, referring to FIG. 8 to FIG. 12, the reception selected when the page of the satellite signal corresponding to the internal time when it is determined that the environmental condition of the reception operation is satisfied is page 16 or page 17. The operation will be specifically described.

  As shown in the condition 1 of FIG. 8, it is within the LS receivable period, the LS information has not been received, and three or more days have passed since the last leap second information receiving operation was performed. When six days or more have elapsed since the execution of the reception operation, the selection unit 47d selects the reception circuit 31 to execute the leap second information reception operation for receiving the LS information (see FIG. 9).

  As shown in the condition 2 in FIG. 8, it is within the LS receivable period, the LS information has not been received, and three or more days have passed since the last leap second information receiving operation was performed. When the number of days elapsed since the execution of the reception operation is less than 6 days, the selection unit 47d selects the reception circuit 31 to execute the leap second information reception operation for receiving the LS information (see FIG. 10). .

  As shown in the condition 3 in FIG. 8, the LS information is within the LS receivable period, the LS information has not been received, and the number of days elapsed since the last leap second information reception operation is less than 3 days. When six days or more have elapsed since the execution of the time information reception operation, the selection unit 47d selects the reception circuit 31 to execute the time information reception operation for receiving the weekly time TOW (FIG. 11). reference).

  As shown in the condition 4 in FIG. 8, the LS information is within the LS receivable period, the LS information has not been received, and the number of days elapsed since the last leap second information reception operation is less than 3 days. When the number of days that have elapsed since the time information reception operation is performed is less than six days, the selection unit 47d selects that the reception circuit 31 does not perform the reception operation (see FIG. 12).

  As shown in the condition 5 in FIG. 8, if the LS information has been received within the LS receivable period and six days or more have elapsed since the previous time information reception operation was performed, the selection unit 47d Then, it is selected that the reception circuit 31 is to execute the time information reception operation for receiving the weekly time TOW (see FIG. 11).

  As shown in condition 6 in FIG. 8, if the LS information has been received and the LS information has been received and the elapsed time is less than 6 days since the previous time information reception operation was performed, the selection is performed. The unit 47d selects not to cause the reception circuit 31 to perform the reception operation (see FIG. 12).

  As shown in condition 7 in FIG. 8, when it is outside the LS receivable period and six days or more have elapsed since the previous time information reception operation was performed, the selection unit 47d receives the weekly time TOW. Therefore, it is selected that the receiving circuit 31 performs the time information receiving operation for the purpose (see FIG. 11).

  As shown in condition 8 in FIG. 8, when it is outside the LS receivable period and the number of days that have elapsed since the previous time information reception operation was performed is less than 6 days, the selection unit 47 d causes the reception circuit 31 to perform the reception operation. Is selected not to be executed (see FIG. 12).

  As described above, in the present embodiment, which reception operation is to be executed or not to be executed based on the page corresponding to the internal time when it is determined that the environmental condition of the reception operation is satisfied. The configuration to select is adopted. Thereby, the leap second information reception operation can be executed at a timing at which the execution time is not unnecessarily prolonged, and as a result, it is possible to suppress an increase in power consumption.

  Further, an operation flow of the control unit 47 from the reception environment check to the execution of the reception operation in the present embodiment will be described with reference to FIG. FIG. 13 is a flowchart showing the operation of the control unit in the present embodiment.

  First, the environment determination unit 47a determines whether or not the radio timepiece 100 is in an environment where satellite signals can be received, based on the detection value detected by the power generation amount detection unit 30 (reception environment check: step S1). That is, the environment determination unit 47a determines whether or not the environment condition for the reception operation is satisfied (step S2). When the environment determination unit 47a determines that the environmental condition of the reception operation is satisfied (YES in step S2), the acquisition unit 47b acquires the internal time when the environment determination unit 47a determines that the environmental condition of the reception operation is satisfied. (Step S3). If the environment determination unit 47a determines that the environmental conditions for the reception operation are not satisfied (NO in step S2), the reception environment check is continued (step S1).

  Further, the signal determination unit 47c determines the page of the satellite signal corresponding to the internal time acquired by the acquisition unit 47b (step S4). When the page determined by the signal determination unit 47c is page 16 or page 17 (YES in step S5), it is within the LS information receivable period (YES in step S6), and LS information has not been acquired (step S7). NO), when three days or more have elapsed since the previous leap second information reception operation was executed (YES in step S8), the selection unit 47d selects that the reception circuit 31 execute the leap second information reception operation. (Step S9).

  On the other hand, the page determined by the signal determination unit 47c is other than page 16 or page 17 (NO in step S5), out of the LS information receivable period (NO in step S6), LS information has been acquired (YES in step S7), the previous time If the number of days elapsed since the execution of the leap second information reception operation corresponds to any of less than 3 days (NO in step S8), the number of days elapsed since the previous time information reception operation was executed is determined (step S10). If six days or more have elapsed since the previous time information reception operation was performed (YES in step S10), the selection unit 47d selects that the reception circuit 31 perform the time information reception operation (step S11). . If the number of days that have elapsed since the previous time information reception operation was performed is less than 6 days (NO in step S10), the selection unit 47d selects that the reception circuit 31 does not perform any reception operation (step S12).

  Next, a first modification of the present embodiment will be described with reference to FIG. FIG. 14 is a flowchart showing the operation of the control unit in the first modification of the present embodiment. In the above-described embodiment, the example in which the reception environment check is always performed at intervals of 10 seconds has been described. However, in the first modification, the reception environment check is performed only when the reception operation needs to be performed. In the first modified example, the power consumption required for the reception environment check can be suppressed because the reception environment check is not performed when the reception operation is not required, such as when the reception operation has already been performed immediately before. It becomes.

  In the first modification, it is within the LS information receivable period (YES in step S21), LS information has not been acquired (NO in step S22), and three or more days have elapsed since the last leap second information receiving operation was executed. Has elapsed (YES in step S23), a reception environment check is performed after setting an execution flag for the leap second information reception operation used in the determination in step S29 described later (step S25). On the other hand, outside the LS information receivable period (NO in step S21), LS information has been acquired (YES in step S22), and the number of days elapsed since the last leap second information receiving operation was performed (NO in step S23) ), It is determined whether or not six days or more have elapsed since the previous time information reception operation was executed (step S24). When six days or more have elapsed since the previous time information reception operation was executed, a reception environment check is performed after setting an execution flag for the time information reception operation used in the determination in step S32 described later (step S25). If the number of days elapsed since the previous time information reception operation was performed is less than 6 days (NO in step S24), the process returns to step S21.

  After performing the reception environment check, the environment determination unit 47a determines whether or not the environment condition of the reception operation is satisfied (step S26). When the environment determination unit 47a determines that the environmental condition of the reception operation is satisfied (YES in step S26), the acquisition unit 47b acquires the internal time when the environment determination unit 47a determines that the environmental condition of the reception operation is satisfied. (Step S27). In addition, when the environment determination part 47a determines with not satisfy | filling the environmental conditions of receiving operation (NO of step S26), it returns to step S21.

  Further, the signal determination unit 47c determines the page of the satellite signal corresponding to the internal time acquired by the acquisition unit 47b (step S28). Then, it is determined whether the execution flag for the leap second information receiving operation is set (step S29). When the execution flag of the leap second information reception operation is set (YES in step S29), it is determined whether the page determined by the signal determination unit 47c is the page 16 or the page 17 (step S30). When the page determined by the signal determination unit 47c is the page 16 or the page 17 (YES in step S30), the selection unit 47d selects the reception circuit 31 to execute the leap second information reception operation (step S31). The leap second information reception operation may be started after waiting for subframe SF4 or 5 on page 17 (see FIG. 6). On the other hand, if the execution flag for the leap second information reception operation is not set (NO in step S29), or the execution flag for the leap second information reception operation is set, the page determined by the signal determination unit 47c is page 16 or If it is not page 17 (NO in step S30), it is determined whether or not an execution flag for the time information reception operation is set (step S32). When the execution flag for the time information reception operation is set (YES in step S32), the selection unit 47d selects that the reception circuit 31 execute the time information reception operation (step S32). When the execution flag of the time information reception operation is not set (NO in step S32), the selection unit 47d selects that the reception circuit 31 does not execute the reception operation.

  Furthermore, with reference to FIG. 15, a second modified example of the present embodiment will be described. FIG. 15 is a flowchart showing the operation of the control unit in the second modification of the present embodiment. In the second modification, the internal time is acquired before the reception environment check is performed, and it is determined whether the reception environment check is performed based on the page of the satellite signal corresponding to the internal time. In the second modified example, when the timing is not suitable for the reception environment check, the reception environment check is not performed, so that the power consumption required for the reception environment check can be suppressed. In addition, the same code | symbol is attached | subjected about the same step as a 1st modification, and the description is abbreviate | omitted.

  The control unit 47 acquires the internal time at the time when Step S23 or Step S24 is executed (Step S40). Then, based on the acquired internal time, it is determined whether the timing is suitable for the reception environment check corresponding to each reception operation (step S41). If it is determined that the time is suitable for the reception environment (YES in step S41), specifically, if it is determined in step S23 that three or more days have elapsed since the previous leap second information receiving operation, step If the page of the satellite signal corresponding to the internal time acquired in S40 is any one of 15 to 17, a reception environment check is performed (step S25). When the page corresponding to the internal time before the reception environment check is immediately before pages 16 to 17 that are timings suitable for starting execution of the leap second information reception operation, the reception environment corresponding to the leap second information reception operation This is because the timing is suitable for checking. If it is determined in step S24 that 6 days or more have elapsed since the previous time information reception operation, the page corresponding to the internal time acquired in step S40 is suitable for the reception environment check regardless of which page is used. Is determined (YES in step S41), and a reception environment check is performed (step S25). After performing the reception environment check, similarly to the first modification, the acquisition unit 47b acquires the internal time when the environment determination unit 47a determines that the environmental condition of the reception operation is satisfied (step S27). The signal determination unit 47c determines the page of the satellite signal corresponding to the internal time acquired by the acquisition unit 47b (step S28). When the execution flag of the leap second information reception operation is set (YES in step S29), the page of the satellite signal corresponding to the internal time acquired by the acquisition unit 47b is 16 or 17 (step S30). YES), the selection unit 47d selects the reception circuit 31 to execute the leap second information reception operation (step S32). The leap second information reception operation may be started after waiting for subframe SF4 or 5 on page 17 (see FIG. 6). On the other hand, if the execution flag for the leap second information reception operation is not set (NO in step S29), or the execution flag for the leap second information reception operation is set, the satellite signal corresponding to the internal time acquired by the acquisition unit 47b If the page is not 16 or 17, the selection unit 47d selects the reception circuit 31 to execute the time information reception operation (step S33).

  The acquisition of the internal time in step S27 may be performed by directly acquiring the internal time when it is determined that the environmental condition of the reception operation is satisfied, or at the internal time acquired in step S40, step S25 may be performed. The calculation may be performed by adding the time required for step S26.

  In addition, it is good also as a structure which a user can confirm the progress of each step shown in FIGS. Specifically, for example, a stop display indicating a state in which the reception environment check is stopped, a start display indicating that the reception environment check has started, or a reception environment check has been successful, and the reception circuit 31 has been activated. It is preferable that the dial 2 is provided with a display during reception indicating that the user can check by pointing them with a pointer. Accordingly, it is possible to prompt the user to move the radio timepiece 100 to an environment suitable for the reception environment. Similarly, an indication that the LS information has been received and an indication that the LS information has not been received are provided on the dial 2, and the user can confirm whether or not the LS information has been received by pointing them with a pointer. It may be configured. Further, a warning display indicating that the LS information has not been received and the remaining days until the leap second update scheduled date is small is provided on the dial 2, and the radio timepiece 100 is moved to an environment where the LS information can be received. It may be configured to prompt the user. Furthermore, it is preferable that the warning level is switched so that the user can easily notice the warning display as the remaining number of days decreases, such as 20 days, 10 days, and 5 days. For example, as the number of remaining days decreases, the movement of the hand movement may be increased, the rotation speed of the hand movement may be increased, or the pointer used for warning display may be switched to a conspicuous one. Moreover, when LS information is not received, it is good also as a structure which starts reception operation | movement compulsorily according to the request | requirement from the user by input means, such as the crown 6 and the button 7.

  In this embodiment and each modified example, the signal unit is a page, and it is configured to determine which reception operation is performed for each page of the satellite signal corresponding to the internal time acquired by the acquisition unit 47b. However, it is not limited to this. For example, the signal unit may be a subframe SF, and it may be determined which reception operation is performed for each subframe SF corresponding to the internal time acquired by the acquisition unit 47b. Specifically, the leap second information reception operation is executed only when the satellite signal corresponding to the internal time acquired by the acquisition unit 47b is the subframe SF3 of page 16 to the subframe SF3 of page 17, and the other subframes SF In this case, the time information receiving operation may be executed or any receiving operation may not be executed.

  In the above-described embodiment and each modified example, the example in which light detection is performed using the solar cell 11 has been described. However, the present invention is not limited thereto, and for example, the presence or absence of sunlight is determined using an ultraviolet sensor. Thus, the reception environment may be determined. Alternatively, the reception environment may be determined by detecting the amount of received light by performing image analysis using an image sensor such as a camera.

  In the above-described embodiment and each modified example, the example in which the determination as to whether or not the environmental condition of the reception operation is satisfied is performed based on the power generation amount (light reception amount) detected by the power generation amount detection unit 30 has been described. However, the present invention is not limited to this, and may be performed based on other information as long as it can be determined whether the radio timepiece 100 is outdoors or indoors. For example, when an acceleration sensor is used as a detection means and the acceleration sensor outputs information that it is determined that the user of the radio timepiece 100 is running, the radio timepiece 100 is outdoors, and the radio timepiece 100 receives a satellite signal. It can be determined that the environment is suitable for reception. That is, it can be determined that the environmental condition of the receiving operation is satisfied. Further, for example, when a sound sensor is used as detection means, the sound sensor acquires environmental sound around the radio clock 100, and information that determines that the radio clock 100 is outdoors is detected, the radio clock 100 is a satellite. It can be determined that the environment is suitable for receiving the signal.

  The reception environment check may be always performed at intervals of 10 seconds, or the time to be performed and the time not to be performed may be divided according to the time zone. For example, it may be set so that the reception environment check is not performed in the midnight time zone. The reception environment check may be performed when a request from the user is made by an input means such as the crown 6 or the button 7.

  The radio timepiece 100 may further include a temperature measuring device that measures the time based on the oscillation frequency of the oscillator and measures the use environment temperature of the radio timepiece 100. The oscillator has a temperature characteristic, and there is a risk of yield rate deviation in an environment of abnormal temperature (for example, −10 ° C. or lower or 60 ° C. or higher). For this reason, in an environment of abnormal temperature, the accuracy of the internal time is lowered, and the target satellite signal may not be received even if the reception operation is performed. In addition, the reception operation itself may not be executed normally under an abnormal temperature environment. Therefore, when the temperature measuring device detects an abnormal temperature, it is preferable that the reception environment check is not executed. Thereby, power consumption required for the reception environment check can be suppressed. In addition, when it is no longer in the environment of abnormal temperature, for example, when a temperature measuring device detects 5 to 40 degreeC, it is good to enable execution of a reception environment check.

  The signal received by the radio timepiece 100 is not limited to that transmitted from a GPS satellite. For example, a signal transmitted by a QZSS (Quasi-Zenith Satellite System) or a GLONASS (Global Navigation Satellite System) It is also possible to adopt a configuration that enables reception corresponding to the plurality of satellites. Further, by selecting a satellite having a large number of satellites arranged in orbit from these satellites and receiving a signal including LS information transmitted from the selected satellite, the success rate of receiving LS information is improved. Can be expected. Note that the update timing of the LS information is that the satellite signal from the GPS satellite is the earliest, and therefore, in the case of a configuration corresponding to a plurality of satellites, it is preferable to preferentially select the GPS satellite.

  As mentioned above, although embodiment concerning this invention was described, the specific structure shown in this embodiment was shown as an example, and it is not intending limiting the technical scope of this invention to this. Those skilled in the art may appropriately modify these disclosed embodiments, and it should be understood that the technical scope of the invention disclosed herein includes such modifications.

  1 body, 2 dial, 3 hour hand, 4 minute hand, 5 second hand, 6 crown, 7 button, 8 band fixing part, 9 windshield, 10 back cover, 11 solar cell, 12 base member, 14 patch antenna, 14a receiving surface, 14b Power supply pin, 23 motor, 24 circuit board, 25 gear mechanism, 26 battery, 29 switch, 30 power generation amount detection unit, 31 reception circuit, 46 high frequency circuit, 47 control unit, 47a environment determination unit, 47b acquisition unit, 47c signal Determination unit, 47d selection unit, 53 decoder circuit, 56 switches, 100 radio timepiece.

Claims (8)

A radio timepiece having a receiving means for performing a satellite signal receiving operation including a plurality of signal units transmitted in time order,
Detecting means for detecting information related to the reception environment of the radio timepiece;
An environment determination means for determining whether or not an environmental condition of the reception operation is satisfied based on information on the reception environment;
An acquisition means for acquiring an internal time held by the radio timepiece when it is determined by the environment determination means that an environmental condition of the reception operation is satisfied;
Signal determination means for determining the signal unit corresponding to the internal time acquired by the acquisition means;
Based on the signal unit determined by the signal determination unit, the reception operation for receiving information on the current time included in the satellite signal or information on a future leap second included in the satellite signal is received. Selecting means for selecting whether or not to cause the receiving means to execute the receiving operation for,
A radio clock. The selection means is information related to the current time based on the signal unit determined by the signal determination means and the number of days elapsed since the reception operation for receiving the information related to the current time was executed last time. Selecting whether to cause the receiving means to perform the receiving operation for receiving
The radio timepiece according to claim 1. The selection means is based on the signal unit determined by the signal determination means, and the future leap second based on the number of days elapsed since the reception operation for receiving the information related to the future leap second was previously executed. Selecting whether to cause the receiving means to perform the receiving operation for receiving information on
The radio timepiece according to claim 1 or 2. The selection unit receives the reception operation for receiving information on the future leap second based on whether the signal unit determined by the signal determination unit and information on the future leap second have been received. Select whether to make the means execute,
The radio timepiece according to any one of claims 1 to 3. The selection unit performs the reception operation of receiving information on the future leap second based on the signal unit determined by the signal determination unit and whether the information on the future leap second is within a receivable period. Selecting whether to cause the receiving means to execute,
The radio timepiece according to any one of claims 1 to 4. The signal unit is a page of the satellite signal.
The radio timepiece according to any one of claims 1 to 5. The signal unit is a subframe of the satellite signal.
The radio timepiece according to any one of claims 1 to 5.   The environment determining unit is configured to receive the information related to the current time when the reception operation for receiving the information related to the future leap second has been performed for the first time since the previous operation was performed or when the information related to the current time is received. 2. The radio timepiece according to claim 1, wherein a determination is made as to whether or not an environmental condition of the reception operation is satisfied only in any case where the second day or more has elapsed since the operation was executed last time.

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