JP6131554B2 - Electronic clock and satellite signal receiving method of electronic clock - Google Patents

Description

  The present invention relates to an electronic timepiece that receives a satellite signal transmitted from a position information satellite such as a GPS satellite and obtains the current date, time, etc., and a satellite signal receiving method for the electronic timepiece.

An electronic timepiece that receives a satellite signal transmitted from a position information satellite such as a GPS (Global Positioning System) satellite and corrects the time has been proposed (Patent Document 1).
The electronic timepiece changes the time limit (time-out time) for generating time correction information based on the number of captured position information satellites and the reception level of the satellite signal transmitted from the position information satellite.
As a result, when the number of captured satellites increases or the reception level of the satellite signal becomes high and it can be determined that the reception environment is good, it is possible to increase the reception success rate by increasing the time limit. .
On the other hand, if the number of captured satellites is small or the reception level of the satellite signal is low and it can be determined that the reception environment is poor, the time limit is shortened to prevent unauthorized power consumption. Can do.

JP 2010-60456 A

However, since the electronic timepiece controls the timeout time by a combination of the number of captured satellites and the reception level of the satellite signal, the reception control process is complicated.
For this reason, a high-performance control device is required, and the power consumption increases accordingly. Therefore, a battery-driven electronic timepiece such as a wristwatch has a problem that it is difficult to realize the control of Patent Document 1 because the duration is short.

  An object of the present invention is to provide an electronic timepiece and a satellite signal receiving method for an electronic timepiece that can simplify the reception control processing and can be realized by a low-function control device and can reduce power consumption.

  The electronic timepiece of the present invention captures a position information satellite, generates a reception unit that receives a satellite signal transmitted from the captured position information satellite, and is generated based on acquired information acquired from the satellite signal received by the reception unit. An electronic timepiece comprising a generation unit that generates information, a display unit that displays the generation information, and a reception control unit that controls the reception unit, wherein the reception control unit obtains from the satellite signal. An acquisition information setting unit that sets the type of information, a satellite acquisition control unit that controls the reception unit to execute a acquisition process of the position information satellite, the number of acquired satellites of the acquired position information satellite, and the acquired position information The reception signal level of the satellite signal received from the satellite is confirmed at predetermined time intervals set in advance, and it is determined whether the reception condition set according to the type of acquisition information set by the acquisition information setting unit is satisfied. The reception state determination unit and the reception state determination unit stop the reception when it is determined that the reception condition is not satisfied, and continue the reception when it is determined that the reception condition is satisfied, and the acquisition information is acquired. Or a reception stop control unit that stops reception when a preset time-out time has elapsed since the start of reception processing.

Here, the type of the acquired information is set according to the type of generated information displayed on the display unit. For example, time information, positioning calculation information used for positioning calculation, date information, leap second information, and the like can be set.
According to the present invention, the acquisition information setting unit sets the type of acquisition information acquired from the satellite signal. At this time, the acquisition information may be set by a user operating an electronic clock button or the like, or may be automatically set by an acquisition information setting unit. In addition, the satellite acquisition control unit performs a position information satellite acquisition process.
Then, the reception state determination unit checks the number of captured satellites and the reception signal level at predetermined time intervals set in advance, and determines whether the reception conditions set according to the acquired information are satisfied. For example, when acquiring time information, if one or more satellites having a reception signal level equal to or higher than a predetermined threshold are captured, it is determined that the reception condition is satisfied. In addition, what is necessary is just to set the threshold value set beforehand to the signal level which can acquire correct acquisition information, such as "30" by SNR (signal to noise ratio), for example.

The reception stop control unit stops the reception when it is determined that the reception condition is not satisfied at the confirmation at the predetermined time interval, and continues the reception when the reception condition is satisfied. Further, the reception stop control unit stops the reception when the acquisition information is acquired or when the elapsed time from the start of the reception process reaches the timeout time.
In this way, the reception stop control unit controls the continuation or stop of reception based on the confirmation result of whether or not the reception condition at a predetermined time interval is satisfied. Also, the timeout time for ending the reception process when the acquisition information cannot be acquired is also fixed according to the type of acquisition information.
For this reason, the reception control can be simplified as compared with the conventional case where the timeout time is changed and controlled by the number of captured satellites and the reception level.
Therefore, the reception control process can be simplified and realized with a low-function control device, and the power consumption can be reduced. For this reason, the reception control of the present invention can be incorporated into a battery-powered wristwatch such as a secondary battery charged by a solar battery.
In addition, if the reception condition at the predetermined time interval is not satisfied, reception is stopped even within the timeout period, so that the reception processing is not continued unnecessarily in a bad reception environment and wasted power consumption. Can be suppressed, and the duration can be increased.
Furthermore, when it is determined that the condition is not satisfied when the reception condition is determined, the reception is immediately stopped, so that the user can be notified early that the reception is difficult. Therefore, the user can change the reception environment, and the probability of successful reception can be improved by performing the forced reception operation again.

  In the electronic timepiece according to the aspect of the invention, the reception condition determination unit determines that the reception condition is that one or more position information satellites having a reception signal level equal to or higher than a predetermined threshold are captured when the type of the acquired information is time information. It is preferable to set as

The time information can be acquired from a satellite signal transmitted from one position information satellite. Therefore, if one or more position information satellites having a received signal level equal to or higher than a predetermined threshold are captured, time information can be acquired by continuing reception.
On the other hand, when no position information satellite having a received signal level equal to or higher than the predetermined threshold value can be captured, it is unlikely that time information can be acquired even if reception is continued. In this case, since reception can be stopped, useless reception processing is not continued and power consumption can be suppressed.

  In the electronic timepiece according to the aspect of the invention, the reception state determination unit may capture two or more position information satellites having a reception signal level equal to or higher than a predetermined threshold when the type of the acquired information is positioning calculation information used for positioning calculation. It is preferable that the reception condition is set.

The positioning calculation information used for positioning calculation is orbit information such as ephemeris, and can be acquired from satellite signals transmitted from four position information satellites. For this reason, if two or more position information satellites having a received signal level equal to or higher than a predetermined threshold are captured, it can be estimated that the electronic timepiece is arranged at a location suitable for receiving the satellite signal. Therefore, by continuing reception, it is highly possible that other position information satellites can be captured and time information can be acquired.
On the other hand, when only one position information satellite with a received signal level equal to or higher than a predetermined threshold can be captured, for example, it can be assumed that there is an environment where only one satellite signal can be received indoors from a window, and reception is continued. However, it is unlikely that information for positioning calculation can be acquired. In this case, since reception can be stopped early, useless reception processing is not continued and power consumption can be suppressed.

  In the electronic timepiece of the invention, the reception state determination unit captures two or more position information satellites having a reception signal level equal to or higher than a predetermined threshold when the type of the acquired information is date information or leap second information. Is preferably set as the reception condition.

Date information and leap second information can be acquired from a satellite signal transmitted from one position information satellite. To check data consistency, information from multiple satellites can be obtained to obtain the same value. It is preferable to confirm.
For this reason, if two or more position information satellites having a received signal level equal to or higher than a predetermined threshold are captured, satellite signals can be received from a plurality of position information satellites and matched by continuing reception. Information and leap second information can be acquired reliably.
On the other hand, when only one position information satellite with a received signal level equal to or higher than a predetermined threshold can be captured, for example, it can be assumed that there is an environment where only one satellite signal can be received indoors from a window, and reception is continued. However, the possibility of acquiring information from multiple satellites is low. In this case, since reception can be stopped, useless reception processing is not continued and power consumption can be suppressed.

  In the electronic timepiece of the invention, the reception state determination unit performs a first confirmation of the number of captured satellites and the reception signal level when a first predetermined time has elapsed after the start of reception processing. It is preferable to confirm the number of captured satellites and the received signal level at intervals of a second predetermined time shorter than the predetermined time.

According to the present invention, after the reception process is started, the first reception state is confirmed after the elapse of a first predetermined time (for example, 30 seconds), and thereafter, the second predetermined time (which is shorter than the first predetermined time) For example, the reception state is confirmed every 15 seconds.
If the time until the first judgment after the start of the reception process is short, it may not be possible to meet that condition, especially if the acquisition of multiple satellites is a condition for continued reception. Rise. In this case, after the start of reception, the reception is stopped by the first determination, and the probability of acquiring information decreases.
In the present invention, since the first determination is made after the first predetermined time has elapsed, if the reception environment is good, a plurality of satellites can be captured and the reception can be continued and the reception can be continued.
Further, since the reception condition is determined at the second predetermined time interval after the second time, even when the reception condition is deteriorated and the satellite cannot be captured, it can be detected quickly. Therefore, it is possible to prevent continuous useless reception.

  In the electronic timepiece of the invention, the reception stop control unit sets the timeout time to a first timeout time when the type of the acquired information is time information, and when the type of the acquired information is other than the time information. Preferably, the timeout time is set to a second timeout time longer than the first timeout time.

In the present invention, the timeout time is fixed according to the type of acquired information. This timeout time can be set to the same time for all pieces of acquired information. On the other hand, as in the present invention, when the acquired information is time information, the first timeout time (for example, 60 seconds) is set, and in the case of other information, the second timeout time (longer than the first timeout time) is set. Yes, for example, 120 seconds).
With such a configuration, the reception condition is satisfied and the reception is continued, but the state where information cannot be acquired does not continue longer than necessary. At this time, since the time information can be acquired in a shorter reception time than other information, even if the first timeout time is shorter than the second timeout time, the opportunity to acquire the time information is set to be equal to other information. it can.

  The present invention captures a position information satellite, receives a satellite signal transmitted from the captured position information satellite, and generates generation information based on acquired information acquired from the satellite signal received by the reception section. A satellite signal reception method for an electronic timepiece, comprising: a generation unit that performs display; a display unit that displays the generation information; and a reception control unit that controls the reception unit. An acquisition information setting step for setting, a satellite acquisition control step for controlling the receiving unit to execute the acquisition process of the location information satellite, the number of acquired acquisition satellites of the location information satellite and the received location information satellite The reception signal level of the satellite signal is confirmed at predetermined time intervals set in advance, and it is determined whether the reception condition set according to the type of acquisition information set in the acquisition information setting step is satisfied. When it is determined that the reception condition is not satisfied in the reception state determination step and the reception state determination step, the reception is stopped, and when it is determined that the reception condition is satisfied, the reception is continued and the acquisition information is acquired. Or a reception stop control step of stopping reception when the elapsed time from the start of reception processing reaches a preset time-out time.

Also in the present invention, as with the electronic timepiece, since it is only necessary to determine whether or not the reception condition is satisfied at regular time intervals, the determination can be made with simple control. Therefore, the reception control process can be simplified and realized with a low-function control device, and the power consumption can be reduced. For this reason, the receiving method of the present invention can be incorporated in a battery-powered wristwatch such as a secondary battery charged by a solar battery.
In addition, since reception is stopped when the reception condition at a predetermined time interval is not satisfied, reception processing is not continued unnecessarily in a bad reception environment, wasteful power consumption can be suppressed, and the duration is also increased. Can be long.
Furthermore, when it is determined that the condition is not satisfied when the reception condition is determined, the reception is immediately stopped, so that the user can be notified early that the reception is difficult. Therefore, the user can change the reception environment, and the probability of successful reception can be improved by performing the forced reception operation again.

It is a top view which shows the electronic timepiece of this invention. It is a block diagram which shows the circuit structure of the said electronic timepiece. It is a figure explaining the structure of a navigation message. It is a flowchart which shows the procedure at the time of a reception control process. It is a timing chart which shows the example of change of the number of acquisition satellites at the time of reception control processing. It is a flowchart which shows the procedure of the modification of this invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
[Structure of electronic watch]
As shown in FIG. 1, the electronic timepiece 1 receives satellite signals from a plurality of GPS satellites 100 (positional information satellites of the present invention) orbiting the earth over a predetermined orbit. At this time, the electronic timepiece 1 receives satellite signals from at least one GPS satellite 100 when acquiring time information, and at least when acquiring positioning calculation information (orbit information such as ephemeris). It is configured to receive satellite signals from three (preferably four) GPS satellites 100. A plurality of GPS satellites 100 exist above the earth. Currently, about 30 GPS satellites 100 orbit.

The electronic timepiece 1 is a wristwatch worn on a user's wrist, and includes a dial 11 and hands 12, and measures and displays time.
Most of the dial 11 is formed of a non-metallic material (for example, plastic or glass) that easily transmits light and microwaves in the 1.5 GHz band.
The pointer 12 includes a second hand 121, a minute hand 122, and an hour hand 123, and is provided on the surface side of the dial 11.

The electronic timepiece 1 includes a crown 14 and buttons 15 and 16 as input units. The electronic timepiece 1 executes processing according to manual operation of the crown 14, the button 15, and the button 16. For example, when the crown 14 is operated, a manual correction process for correcting the display time according to the operation is executed.
When the button 15 is pressed for a long time (for example, 3 seconds or more), reception processing for receiving satellite signals is executed (manual reception mode).
When the button 16 is pressed, processing for switching the reception mode (time measurement mode, positioning mode, or automatic reception invalid mode) is executed. When the positioning mode is set as a result of the reception mode switching process according to the operation of the button 16, the second hand 121 moves to the “Fix” position (5 second position) and is set to the time measuring mode. When the second hand 121 is moved to the “Time” position (10-second position) and set to the automatic reception invalid mode (reception OFF mode), the second hand 121 is set to the “Off” position (50-second position). Move to. For this reason, the user can easily confirm the set reception mode.

When the button 15 is pressed for a short time (for example, less than 3 seconds), a result display process for displaying the result of the previous reception process is performed. That is, when the reception is successful in the positioning mode, the second hand 121 moves to the position “Fix” (5 second position), and when the reception is successful in the time measurement mode, the second hand 121 is “Time” (10 second position). ) Position. In the case of reception failure, the second hand 121 moves to the “N” position (20-second position).
Note that these instructions by the second hand 121 are also performed during reception. During reception in the positioning mode, the second hand 121 moves to the “Fix” position (5 second position), and during reception in the time measurement mode, the second hand 121 moves to the “Time” position (10 second position). When the GPS satellite cannot be captured, the second hand 121 moves to the “N” position (20-second position).

The electronic timepiece 1 performs not only the manual reception process by the button 15 but also the scheduled automatic reception process for automatically receiving at the set reception time.
The set reception time is a preset time such as 2 am, 3 am, 7 am, 8 am or the like. Setting at 2 am or 3 am is highly likely that the electronic watch 1 is removed from the user and placed on a desk near the window in a non-wearing state, and there is little use of electrical products. This is because the influence of noise can be reduced and the radio wave reception environment is likely to be good. Also, the setting of 7 am or 8 am is for the commuting time zone, because the user wearing the electronic timepiece 1 is outdoors and easily receives satellite signals. However, it is not limited to these times, and the user may set the automatic reception time.

[Circuit configuration of electronic watch]
FIG. 2 is a block diagram showing a circuit configuration of the electronic timepiece 1. As shown in this figure, the electronic timepiece 1 includes a GPS antenna 20, a GPS receiving circuit 30, a control circuit 40, a storage unit 50, a clock unit 60, a power generation device 70, and a secondary battery 80.

  The power generation device 70 includes a solar panel and a charge control circuit. Then, the secondary battery 80 is charged with the power generated by the power generation device 70. Each device of the electronic timepiece 1 is driven by electric power supplied from the secondary battery 80.

[Receiver]
The GPS antenna 20 is an antenna that receives microwaves in the 1.5 GHz band, and is disposed on the back side of the dial 11. In the direction orthogonal to the dial plate 11, the portion of the dial plate 11 that overlaps the GPS antenna 20 is formed of a material that easily transmits 1.5 GHz band microwaves (for example, a non-metallic material with low conductivity and low permeability). Has been.
Further, a solar panel having electrodes is not interposed between the GPS antenna 20 and the dial 11. Therefore, the GPS antenna 20 can receive the satellite signal that has passed through the dial 11.

  Although not shown, the GPS receiving circuit 30 mainly includes an RF (Radio Frequency) unit and a GPS signal processing unit. The RF unit and the GPS signal processing unit perform processing to acquire satellite information such as orbit information and GPS time included in the navigation message from the 1.5 GHz band satellite signal.

  The RF unit is a general one in a GPS receiver including a down converter that converts a high-frequency signal into a signal in an intermediate frequency band, an A / D converter that converts an analog signal in the intermediate frequency band into a digital signal, and the like. .

Although not shown, the GPS signal processing unit includes a DSP (Digital Signal Processor), a CPU (Central Processing Unit), an SRAM (Static Random Access Memory), an RTC (Real Time Clock), etc., and is output from the RF unit. The navigation message is demodulated from the digital signal (intermediate frequency band signal), and the satellite information such as orbit information and GPS time included in the navigation message is acquired.
Therefore, in the present embodiment, the GPS antenna 20 and the GPS receiving circuit 30 constitute a receiving unit that receives a satellite signal transmitted from a GPS satellite.
Note that the GPS receiving circuit 30 of this embodiment includes a 12-channel receiving circuit so that 12 satellite signals can be simultaneously captured and received.

[Control circuit]
The control circuit 40 includes a CPU for controlling the electronic timepiece 1 and includes a generation unit 41, a reception control unit 42, and a display control unit 43.
The generation unit 41 acquires time information and positioning calculation information from satellite signals received by the GPS antenna 20 and the GPS reception circuit 30, and generates generation information such as time information and current location information from the acquired information. Store in the storage unit 50.

  Furthermore, the generation unit 41 updates the internal time data by counting reference signals generated by a crystal oscillator and an oscillation circuit (not shown). The internal time data is a local time obtained by correcting the reception time data with a UTC offset and further correcting with time difference information. For this reason, when receiving the satellite signal, the generation unit 41 corrects the received reception time data with the UTC offset and the time difference information and updates the internal time data. In addition, the generation unit 41 updates the internal time data with the reference signal when no satellite signal is received.

The reception control unit 42 includes a GPS reception circuit during a scheduled automatic reception process that is executed when the internal time data reaches a preset reception time and during a manual reception process that is executed by operating the buttons 15 and 16. 30 is controlled to perform GPS signal reception processing.
Therefore, the reception control unit 42 includes an acquisition information setting unit 421, a satellite acquisition control unit 422, a reception state determination unit 423, and a reception stop control unit 424.
The acquisition information setting unit 421 sets the type of acquisition information A acquired from the satellite signal, as will be described later. The satellite acquisition control unit 422 controls the GPS receiving circuit 30 to execute acquisition processing for all GPS satellites 100.

The reception state determination unit 423 confirms the number of captured satellites of the captured GPS satellite 100 and the reception signal level of the satellite signal received from the captured GPS satellite 100 at intervals of a predetermined time I set in advance, and sets acquired information It is determined whether a reception condition set according to the type of acquisition information A set by the unit 421 is satisfied.
The reception stop control unit 424 stops reception when the reception state determination unit 423 determines that the reception condition is not satisfied, and continues reception when it is determined that the reception condition is satisfied, and the acquisition information A is acquired. Or when the elapsed time from the start of the reception process exceeds a preset timeout time T, the reception is stopped.

The display control unit 43 controls the driving of the clock unit 60 to display the current time. The clock unit 60 includes a pointer 12 and a motor that drives the pointer 12.
Further, when acquiring the positioning calculation information, the display control unit 43 instructs the time zone corresponding to the position information of the current location as the positioning result generated from the positioning calculation information with the second hand 121 or the like. That is, an abbreviation of a city name indicating a time zone (not shown) is displayed on the outer periphery of the dial 11. When the positioning calculation information is acquired and the location information of the current location is generated, the display control unit 43 instructs the city name of the time zone including the location information with the second hand 121 for a certain period of time.
Therefore, the clock unit 60 and the display control unit 43 constitute a display unit that displays the generation information generated by the generation unit 41 such as time information.
Further, the display control unit 43 normally drives the hands 12 in conjunction with the update of the internal time data by the reference signal. When the satellite signal is received and the internal time data is corrected based on the received time data, the pointer 12 is driven in conjunction with the correction so that the correct time is displayed.

[Storage unit]
The storage unit 50 stores acquisition information acquired by the GPS receiving circuit 30 and generation information generated by the generation unit 41. For example, the storage unit 50 stores reception time data (satellite time information), positioning calculation information (orbit information and the like), positioning result position information, UTC offset, time difference information, and internal time data.

  The UTC offset is obtained by acquiring and storing “current leap second” information included in subframe 14 and page 18 of the GPS satellite signal.

  The time difference information is time difference data for correcting UTC to local time. The time difference data may be set by the user operating the crown 14 or the buttons 15 and 16, or the position information generated from the positioning calculation information acquired at the time of receiving in the positioning mode (during the positioning process). You may set based on. When obtaining time difference data with the generated position information, a correspondence table between position information (positioning result) and time difference data (time zone) may be stored in the storage unit 50.

The storage unit 50 also stores the determination conditions in Table 1 used in the reception state determination program (logic).

As shown in Table 1, five types of determination conditions are set: acquisition information type, received signal level threshold value, number of captured satellites, reception state confirmation time interval, and timeout time.
The acquired information type indicates the type of information acquired from the satellite signal, and specifically includes four types of information: “time information, positioning calculation information, date information, leap second information”.

The received signal level threshold is a threshold for determining the GPS satellite 100 being captured. That is, when the reception state is determined, the GPS satellite 100 whose received signal level exceeds this threshold is determined as a captured satellite.
In the present embodiment, the received signal level threshold values are all the same value (SNR: 30), but may be changed according to the type of acquired information. In addition, SNR: 30 is generally equivalent to -140 dBm.

The number of captured satellites is a threshold value for determining whether the reception condition is satisfied. For example, it is determined that the reception condition is satisfied when there are more GPS satellites 100 that have received signal levels equal to or higher than the threshold when the reception condition is determined.
The number of captured satellites is set corresponding to the type of acquired information. Specifically, when the acquired information is time information, the number of captured satellites is set to “1”, when it is positioning calculation information, it is set to “2”, and when it is date information and leap second information, “2”. "Is set.

  The reception state confirmation time interval is a predetermined time interval for determining whether or not the reception condition is satisfied. Specifically, the reception state confirmation time interval is set to 15 seconds when the acquired information is time information, and to 30 seconds when the positioning calculation information, date information, and leap second information are each obtained.

  The timeout time sets the timing for ending reception when the acquisition information cannot be acquired. Specifically, the timeout time is set to 60 seconds when the acquired information is time information, and 120 seconds when the information for positioning calculation, date information, and leap second information is used.

[Navigation message]
Here, a navigation message, which is a satellite signal transmitted from the GPS satellite 100 including the acquired information, will be described. The navigation message is modulated into satellite radio waves as 50 bps data.
FIG. 3A to FIG. 3C are diagrams for explaining the configuration of the navigation message.
As shown in FIG. 3 (A), the navigation message is configured as data with a main frame having a total number of 1500 bits as one unit. The main frame is divided into five sub-frames 1 to 5 each having 300 bits. Data of one subframe is transmitted from each GPS satellite 100 in 6 seconds. Accordingly, data of one main frame is transmitted from each GPS satellite 100 in 30 seconds.

Subframe 1 includes week number data (WN: week number) and satellite correction data.
The week number data is information representing a week including the current GPS time information, and is updated on a weekly basis.
Subframes 2 and 3 include ephemeris parameters (detailed orbit information of each GPS satellite 100). The subframes 4 and 5 include almanac parameters (general orbit information of all GPS satellites 100).

  Further, subframes 1 to 5 include, from the beginning, a TLM (Telemetry) word storing 30-bit TLM (Telemetry word) data and a HOW word storing 30-bit HOW (hand over word) data. It is.

  Accordingly, TLM words and HOW words are transmitted from the GPS satellite 100 at intervals of 6 seconds, whereas week number data, satellite correction data, ephemeris parameters, and almanac parameters are transmitted at intervals of 30 seconds.

  As shown in FIG. 3B, the TLM word includes preamble data, a TLM message, reserved bits, and parity data.

  As shown in FIG. 3C, the HOW word includes GPS time information called TOW (Time of Week, also referred to as “Z count”). In the Z count data, the elapsed time from 0 o'clock every Sunday is displayed in seconds, and it returns to 0 at 0 o'clock on the next Sunday. That is, the Z count data is information in units of seconds indicated every week from the beginning of the week. This Z count data indicates GPS time information at which the first bit of the next subframe data is transmitted.

Therefore, the electronic timepiece 1 can acquire date information and time information by acquiring the week number data included in the subframe 1 and the HOW word (Z count data) included in the subframes 1 to 5. However, if the electronic timepiece 1 has previously acquired week number data and is counting the elapsed time since the time when the week number data was acquired internally, the current time of the GPS satellite can be obtained without acquiring the week number data. Can be obtained.
Therefore, the electronic timepiece 1 only needs to acquire the week number data of the subframe 1 only when the week number data (date information) is not stored therein after resetting or when the power is turned on. When the week number data is stored, the electronic timepiece 1 can obtain the current time by acquiring the TOW transmitted every 6 seconds. For this reason, the electronic timepiece 1 usually acquires only TOW as time information.

  As described above, the “leap second information” is obtained by storing the “current leap second” information included in the subframe 4 and the page 18. The subframe 4 and page 18 also include information on “leap second update week, update date, leap second after update”, and when the leap second is updated, the timing is notified in advance. . When the leap second is updated, it is usually executed on the last day of December or June. For this reason, if the electronic timepiece 1 performs the leap second information acquisition process and receives the subframe 14 and the page 18 before a fixed period at the end of December and the end of June, the presence / absence and update of the leap second are present. The leap second correction value can be acquired.

[location information]
In order to generate the position information of the electronic timepiece 1, it is necessary to receive ephemeris parameters transmitted from three or more (preferably four) GPS satellites 100 as positioning calculation information for generating position information. . At this time, when a plurality of GPS satellites 100 are simultaneously captured and received, the ephemeris parameter is received and the positioning calculation is performed, and the position information of the positioning result is obtained. In the cold start state in which the almanac data is not retained, about 30 seconds. ~ 1 minute is required.

[Receive processing]
Next, the reception process of the electronic timepiece 1 will be described with reference to the flowchart of FIG.
As described above, the reception process shown in FIG. 4 is executed when a user's reception operation is performed and when a preset reception time is reached.

When the reception process is executed, the acquisition information setting unit 421 of the reception control unit 42 sets the type of the acquisition information A (S1).
For example, when a manual reception operation is performed in the positioning mode, the reception control unit 42 sets positioning calculation information as the acquisition information A.
In addition, when a manual reception operation is performed in the timekeeping mode or when an automatic reception process is performed, the acquisition information setting unit 421 first stores date information (week number data) in the storage unit 50. Make sure that Then, the acquisition information setting unit 421 sets date information as acquisition information A when date information is not stored, and sets time information as acquisition information A when it is stored.
Furthermore, there is a possibility that the leap second may be updated. It is a predetermined period before the end of December or the end of June, for example, one month from December 1 or June 1, and the leap second information has not been acquired. In addition, when reception processing in the timekeeping mode is performed, leap seconds are set as the acquisition information A.

Next, the reception state determination unit 423 refers to the reception condition setting parameters stored in the storage unit 50 in Table 1 and determines the reception signal level corresponding to the acquisition information A set by the acquisition information setting unit 421. The threshold S, the number N of captured satellites, the predetermined time I of the reception state confirmation time interval, and the timeout time T are set (S2).
For example, when the acquisition information A is time information, the reception state determination unit 423 determines that the SNR threshold S is “30”, the number of captured satellites N is “1”, the predetermined time I is “15 seconds”, and the timeout time T is “ 60 seconds ". In addition, when the acquisition information A is positioning calculation information, the reception state determination unit 423 determines that the threshold S is “30”, the number of captured satellites N is “2”, the predetermined time I is “30 seconds”, and the timeout time T is “ 120 seconds ".
Further, when the acquisition information A is date information or leap second information, the reception state determination unit 423 has an SNR threshold S of “30”, an acquisition satellite number N of “2”, a predetermined time I of “30 seconds”, and a timeout. The time T is set to “120 seconds”.
The leap second information is transmitted every 12.5 minutes. However, if the reception is continued for 12.5 minutes, the current consumption increases. For this reason, the satellite acquisition control unit 422 confirms the page of the subframes 4 and 5 received at the start of reception, calculates the timing at which the subframe 4 and page 18 including leap second information are transmitted next, and the timing. Controls to resume the reception at the same time. The predetermined time I and the timeout time T are counted from the time when the reception is resumed.

  Then, the satellite acquisition control unit 422 starts receiving the satellite signal transmitted from the GPS satellite 100 (S3). Specifically, the satellite acquisition control unit 422 controls the GPS receiving circuit 30 to generate a C / A code pattern of the GPS satellite 100 and start reception. Then, a correlation value between each C / A code and the received satellite signal is obtained, and the GPS satellite 100 that can be synchronized is captured.

Next, the reception state determination unit 423 determines whether the predetermined time I has come (S4). Specifically, it is determined whether the elapsed time from the start of reception is n times the predetermined time I.
Therefore, if the predetermined time I is 15 seconds, it is determined Yes in S4 when the timing is 15 seconds, 30 seconds, 45 seconds, and 60 seconds from the start of reception.
If the predetermined time I is 30 seconds, it is determined Yes in S4 when the timing is 30 seconds, 60 seconds, 90 seconds, and 120 seconds from the start of reception.
On the other hand, if it is determined No in S4, the process returns to the determination process in S4.

If it is determined Yes in S4, the reception state determination unit 423 determines whether or not the GPS satellites 100 whose reception signal level is equal to or greater than the threshold value S have been captured for the number N of captured satellites (S5).
If it determines with Yes by S5, the production | generation part 41 will determine whether the satellite signal was received from the captured GPS satellite 100, and the information A was acquired (S6). For example, when the acquisition information A is time information, the generation unit 41 corrects GPS time information generated from a satellite signal received from one GPS satellite 100 with UTC offset, and further corrects with time difference information to obtain local time If the local time matches the internal time data, it is determined that the time information has been acquired.

When the generation unit 41 acquires date information and leap second information, the date information generated from the satellite signals received from the two GPS satellites 100 and the leap second information are determined based on whether or not the information is the same. It can be determined whether it was acquired.
In addition, when acquiring positioning calculation information, the generation unit 41 generates position information (latitude, longitude) generated by positioning calculation information (ephemeris parameters, etc.) acquired from satellite signals received from four or more GPS satellites 100. It is possible to determine whether or not correct position information (positioning result) has been acquired by checking whether or not (altitude) is within a preset range.

When it is determined Yes in S6, the reception stop control unit 424 ends the reception operation (S7).
In addition, the display control unit 43 moves the second hand 121 to display reception success. As described above, the successful reception display moves the second hand 121 to “FIX” (when positioning calculation information is acquired) and “Time” (when time information, date information, or leap second information is acquired). (S7).
Further, the display control unit 43 corrects the internal time (current time, date, leap second, etc.) and position information with the generated information generated from the acquired information (S7).
Then, the reception control unit 42 ends the reception control process. As a result, the second hand 121 that has been displaying reception success for a certain time also moves to indicate the corrected current time and the like, and returns to the normal time display.

On the other hand, when it is determined No in S6, the reception stop control unit 424 determines whether the timeout time T has elapsed (S8).
For example, when the acquired information is time information, the timeout time T is set to 60 seconds. For this reason, if 60 seconds have elapsed from the start of the reception process and it is determined Yes in S4, Yes in S5, and No in S6, the timeout time T = 60 seconds has elapsed, so Yes in S8. It is determined. On the other hand, from the start of reception until the timeout time T is reached, since it is determined No in S8, the reception control unit 42 returns to the determination process of S4 and continues the control process.

If the information A cannot be acquired and a time-out occurs, for example, the user walks while wearing the electronic watch 1, and the satellite can be captured, but reception is not stable and is likely not suitable for information acquisition. .
Therefore, when it is determined Yes in S8, the reception stop control unit 424 ends the reception operation, and the display control unit 43 displays a reception failure by the second hand 121 (S9). Then, the reception control unit 42 ends the reception control process. As a result, the second hand 121 that has been performing reception failure display for a certain period also returns to the original time display. At this time, since acquisition of the information A has failed, the internal time that has been timed is displayed and the normal time display is restored.

  On the other hand, when it is determined No in S5, that is, when the reception condition is not satisfied at the timing of the predetermined time I, the reception stop control unit 424 ends the reception operation, and the display control unit 43 receives by the second hand 121. A failure is displayed (S9). Then, the reception control unit 42 ends the reception control process.

FIG. 5 is a diagram illustrating an example of determining the reception state when acquiring time information. The reception state determination unit 423 determines the reception state every 15 seconds.
As shown by a solid line 51, when one GPS satellite 100 is captured until 15 seconds from the start of reception, and then GPS satellite 100 is continuously captured, 15 seconds, 30 seconds, 45 seconds, and 60 seconds. Since the reception condition is satisfied at each determination timing, the reception is continued when time information is acquired or until a timeout time is reached.

On the other hand, as indicated by the alternate long and short dash line 52, one GPS satellite 100 is captured by 15 seconds from the start of reception, but if it cannot be captured within 15 to 30 seconds, it is received at the determination timing of 15 seconds. Reception is continued because the condition is satisfied, but reception is stopped because the reception condition is not satisfied at the determination timing of 30 seconds.
Further, as indicated by a two-dot chain line 53, one GPS satellite 100 is captured by 15 seconds from the start of reception and cannot be captured once in 30 seconds to 45 seconds, but it can be captured again. In this case, since the reception condition is satisfied at the determination timing of 15 seconds, 30 seconds, 45 seconds, and 60 seconds, the reception is continued. That is, even if the reception condition is not satisfied other than at the determination timing, the reception is continued as long as the reception condition is satisfied at the determination timing.
Of course, if the reception condition is not satisfied at the determination timing of 15 seconds, the reception is stopped at that point.

According to this embodiment, there are the following effects.
(1) According to the present embodiment, the reception state determination unit 423 determines whether the reception condition is satisfied at an interval of the predetermined time I. Then, the reception stop control unit 424 controls the continuation or stop of the reception based on the confirmation result of whether or not the reception condition at the interval of the predetermined time I is satisfied. Further, the timeout time T for ending the reception process when the acquisition information A cannot be acquired is also fixed according to the type of acquisition information.
Therefore, as compared with the conventional case where the control is performed by changing the timeout time based on the number of captured satellites and the reception level, this embodiment can simplify the reception control. Therefore, the reception control process can be simplified and realized with a low-function control device, and the power consumption can be reduced. For this reason, the reception control of this embodiment can also be incorporated in an electronic timepiece (watch) 1 driven by a secondary battery 80 charged by a solar battery.

(2) In addition, the reception stop control unit 424 stops reception even if it is within the time-out period when the reception condition is not satisfied at the predetermined time I interval. Thus, useless power consumption can be suppressed and the duration of the electronic timepiece 1 can be increased.
Furthermore, if the reception stop control unit 424 determines that the condition is not satisfied when determining the reception condition, the reception stop control unit 424 immediately stops the reception, so that the user can be notified at an early stage that the reception is difficult. Therefore, the user can change the reception environment, and the probability of successful reception can be improved by performing the forced reception operation again.

(3) In this embodiment, when acquiring time information, the number of captured satellites is 1 as a reception condition, and when acquiring positioning calculation information, date information, and leap second information, the number of captured satellites is received as a reception condition. 2. For this reason, it is possible to effectively determine whether or not the GPS satellite 100 suitable for acquisition of each information can be captured, it is possible to improve the probability that each information can be acquired, and it is possible to prevent continued useless reception processing, Power consumption can also be suppressed.

(4) In this embodiment, when acquiring time information, the predetermined time I is 15 seconds and the timeout time T is 60 seconds. When acquiring other information, the predetermined time I is 30 seconds and the timeout time T is 120 seconds. For this reason, it is possible to appropriately determine the reception condition in consideration of the transmission timing of each information.

[Modification]
The present invention is not limited to the above embodiment.
For example, the reception state determination unit 423 sets the predetermined time I until the first determination timing after the start of reception as the first predetermined time I1, the subsequent predetermined time I as the second predetermined time I2, and the second predetermined time I2. May be set to a time shorter than the first predetermined time I1. For example, the first predetermined time I1 may be set to 30 seconds and the second predetermined time I2 may be set to 15 seconds.
In this case, as shown in FIG. 6, in S2, a first predetermined time I1 is set as the predetermined time I. Therefore, after the start of the reception process, the first determination process of S4 is performed when the first predetermined time I1 (for example, 30 seconds) has elapsed. If it is determined No in S8, a second predetermined time I2 (for example, 15 seconds) is set as the predetermined time I. Therefore, the second and subsequent determination processes in S4 are performed when the second predetermined time I2 has elapsed from the previous determination timing.
Therefore, in the flowchart of FIG. 6, after the start of reception, for example, the determination process is performed until the timeout time T, such as 30 seconds (first predetermined time I1), 45 seconds (second predetermined time I2, and so on), 60 seconds, and the like. Is called.
Note that the other processes shown in FIG. 6 are the same as those in the above embodiment, and thus the description thereof is omitted.

According to such a modification, since the first reception determination process is performed after the first predetermined time has elapsed, the determination process can be performed in a stable reception state, and it is necessary to capture a plurality of satellites. Even in this case, the reception state can be correctly determined.
Further, since the reception condition is determined at the second predetermined time I2 after the second reception determination process, even when the reception condition deteriorates and the satellite cannot be captured, it can be detected quickly. Therefore, it is possible to prevent continuous useless reception.

  The first predetermined time I1 and the second predetermined time I2 may be set only when a part of information is acquired. For example, the first and second predetermined times may be set only when acquiring positioning calculation information, or when acquiring two satellites such as positioning calculation information, date information, leap second information, etc. A predetermined time of 1 or 2 may be set.

Furthermore, in the embodiment, when the positioning calculation information is acquired, the number N of captured satellites is “2”, but may be set to “3” or more. That is, in order to acquire the positioning calculation information, it is usually necessary to capture four GPS satellites 100. Therefore, the reception continuation determination condition may be a value larger than “2”.
Further, when date information and leap second information are acquired, the number N of captured satellites may be set to “1” as in the case of time information.
However, in consideration of the fact that date information and leap second information are rarely received, data can be acquired from two satellites at the time of reception so that consistency can be confirmed. N is preferably “2”.

  Further, the automatic reception process is not limited to the automatic reception process on a regular basis, for example, outdoor determination automatic that is automatically received when it is determined that the electronic timepiece 1 is disposed outdoors by detecting the generated power of the solar panel. A reception process may be performed. In addition, what is necessary is just to implement the automatic reception process by this outdoor determination about once a day by implementing after predetermined time progress from the previous outdoor determination automatic reception process.

  The electronic timepiece of the present invention is not limited to an analog timepiece having hands, but may be applied to a combination timepiece having hands and a display, or a digital timepiece having only a display. Furthermore, the present invention is not limited to wristwatches, but is applied to various clocks such as table clocks and pocket watches, various information terminals having clock functions such as mobile phones, digital cameras, PNDs (personal navigation devices), car navigation systems, and the like. May be.

  Moreover, although the above-mentioned embodiment demonstrated the GPS satellite as an example of a position information satellite, not only a GPS satellite but a Galileo (EU), GLONASS (Russia), Hokuto (China) as a position information satellite of this invention. Other global navigation satellite systems (GNSS), etc., or position information satellites that transmit satellite signals including time information such as geostationary satellites such as SBAS and quasi-zenith satellites may be used.

  DESCRIPTION OF SYMBOLS 1 ... Electronic timepiece, 12 ... Hand, 14 ... Crown, 15, 16 ... Button, 20 ... GPS antenna, 30 ... GPS receiving circuit, 40 ... Control circuit, 41 ... Generation part, 42 ... Reception control part, 43 ... Display control , 50 ... storage unit, 60 ... clock unit, 70 ... power generation device, 80 ... secondary battery, 100 ... GPS satellite, 121 ... second hand, 122 ... minute hand, 123 ... hour hand, 421 ... acquisition information setting unit, 422 ... satellite Capture control unit, 423 ... reception state determination unit, 424 ... reception stop control unit.

Claims (9)

A receiver that captures a position information satellite and receives a satellite signal transmitted from the captured position information satellite;
A generation unit that generates generation information based on acquisition information acquired from the satellite signal received by the reception unit;
A display unit for displaying the generation information;
An electronic timepiece comprising a reception control unit for controlling the reception unit,
The reception control unit
An acquisition information setting unit for setting the type of acquisition information acquired from the satellite signal;
A satellite acquisition control unit for controlling the reception unit to execute a position information satellite acquisition process;
The number of captured position information satellites and the received signal level of the satellite signal received from the captured position information satellite are confirmed at predetermined time intervals after the start of the reception process, and set by the acquired information setting unit. A reception state determination unit that determines whether a reception condition set according to the type of acquired information is satisfied,
If the reception state determination unit determines that the reception condition is not satisfied, the reception is stopped. If it is determined that the reception condition is satisfied, the reception is continued, and when the acquisition information is acquired or when the reception process starts. A reception stop control unit for stopping reception when an elapsed time from a preset time-out time has elapsed,
An electronic timepiece characterized by comprising: The electronic timepiece according to claim 1,
The reception state determination unit
When the type of the acquired information is time information, it is set as the reception condition that one or more position information satellites having a reception signal level equal to or higher than a predetermined threshold are acquired as the reception condition. The electronic timepiece according to claim 1,
The reception state determination unit
When the type of acquired information is positioning calculation information used for positioning calculation, it is set as the reception condition that two or more position information satellites having a received signal level equal to or higher than a predetermined threshold are captured. Electronic clock. The electronic timepiece according to claim 1,
The reception state determination unit
When the type of the acquired information is date information or leap second information, it is set as the reception condition that two or more position information satellites having a reception signal level equal to or higher than a predetermined threshold are captured as the reception condition. . The electronic timepiece according to any one of claims 1 to 4,
The reception state determination unit
When the first predetermined time has elapsed after the start of reception processing, a first confirmation of the number of captured satellites and the received signal level is performed, and thereafter, the acquisition is performed at intervals of a second predetermined time shorter than the first predetermined time. An electronic timepiece characterized by checking the number of satellites and the received signal level. The electronic timepiece according to any one of claims 1 to 5,
The reception stop control unit
If the type of acquisition information is time information, the timeout time is set to the first timeout time,
When the type of the acquired information is other than time information, the timeout time is set to a second timeout time longer than the first timeout time. The electronic timepiece according to any one of claims 1 to 6,
The electronic timepiece characterized in that the acquired information includes at least one of time information, positioning calculation information, date information, and leap second information. The electronic timepiece according to any one of claims 1 to 7,
The generation information includes at least one of position information generated based on positioning calculation information, time difference information corresponding to the position information, and internal time data updated based on time information. An electronic watch. A receiver that captures a position information satellite and receives a satellite signal transmitted from the captured position information satellite;
A generation unit that generates generation information based on acquisition information acquired from the satellite signal received by the reception unit;
A display unit for displaying the generation information;
A satellite signal reception method for an electronic timepiece comprising a reception control unit for controlling the reception unit,
An acquisition information setting step for setting the type of acquisition information acquired from the satellite signal;
A satellite acquisition control step of controlling the receiving unit to execute a position information satellite acquisition process;
The number of captured position information satellites and the received signal level of the satellite signal received from the captured position information satellite are confirmed at predetermined time intervals after the start of the reception process, and set in the acquisition information setting step. A reception state determination step for determining whether or not a reception condition set according to the type of acquired information is satisfied,
When it is determined that the reception condition is not satisfied in the reception state determination step, the reception is stopped, and when it is determined that the reception condition is satisfied, the reception is continued, when the acquisition information is acquired or when the reception process starts A reception stop control step for stopping reception when the elapsed time from the time reaches a preset timeout time;
A satellite signal receiving method for an electronic timepiece.

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