JP7477008B2 - Wearable device, positioning control method, and positioning control program - Google Patents

Description

The present invention relates to a wearable device, a positioning control method, and a positioning control program.

In recent years, wearable devices (such as electronic watches) with a positioning function using the Global Positioning System (GPS) have been configured to receive positioning information from a smartphone and refer to that information to speed up the time it takes for the GPS to perform positioning.

Patent document 1 describes an invention that determines whether or not the wrist device stores updated ephemeris data. Patent document 1 also describes that if the wrist device does not store updated ephemeris data, the wrist device obtains updated ephemeris data from a secondary device.

US Patent Application Publication No. 2014/0292566

Wearable devices such as wrist devices often have location information closer to the user's current location than secondary devices such as smartphones. Therefore, if a wearable device uses location information determined by a smartphone instead of using location information determined by the wearable device itself, the location information may be farther away from the user's current location. In such cases, the time it takes for GPS to determine the location may be slow.
Therefore, an object of the present invention is to increase the probability of reducing the time required for GPS positioning for a wearable device, a positioning control method, and a positioning control program.

In order to achieve the above object, the present invention provides
a positioning unit that performs a positioning operation using radio waves received from a satellite and acquires first position information that is the position of the device itself and first time information that is the time when the position of the device itself is acquired;
a communication unit that communicates with a portable external device and receives second position information, which is position information measured by the external device, orbital information related to the satellite, and second time information, which is a time when the external device acquires the second position information;
A control unit;
a storage unit that stores the first location information, the first time information, the second location information, and the second time information;
Equipped with
the control unit causes the positioning unit to perform a positioning operation using the second location information when the second time information stored in the storage unit is closer to a current time than the first time information stored in the storage unit and the second time information stored in the storage unit is within a predetermined time from the current time.
The wearable device is characterized by the above.

The present invention makes it possible to reduce the time required for GPS positioning.

1 is a diagram showing an outline of the configuration of an electronic timepiece according to an embodiment of the present invention; FIG. 1 is a diagram illustrating the configuration of a smartphone. 13 is a flowchart (part 1) of a process in which the watch obtains location information and predicted ephemeris information from a smartphone. 13 is a flowchart (part 2) of the process in which the watch obtains location information and predicted ephemeris information from the smartphone. 13 is a flowchart of a process for turning off the smartphone location use flag after 24 hours have passed. 13 is a flowchart (part 1) of a process performed by an electronic timepiece upon receiving a GPS signal. 13 is a flowchart (part 2) of the process performed by the electronic timepiece upon GPS reception.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic diagram showing the configuration of an electronic timepiece 1 according to this embodiment.
The electronic watch 1 is an example of a wearable device, and includes a CPU (Central Processing Unit) 11, a display 12, a memory 13, a GPS-IC (Integrated Circuit) 14, and a short-range wireless communication unit 15.

The CPU 11 is a processing unit that controls all the components of the electronic watch 1. The display 12 is, for example, a liquid crystal display, and displays the time measured by the CPU 11. The memory 13 is, for example, a flash memory, and stores a positioning control program (not shown) to be executed by the CPU 11. The memory 13 is also a storage unit that stores position information (first position information) acquired by the GPS-IC 14, time information (first time information) at the time when the position of the first position information is measured, position information (second position information) acquired by the short-range wireless communication unit 15, and time information (second time information) at the time when the position of the second position information is measured. Note that the memory 13 is not limited to being composed of a flash memory.

The GPS-IC14 (an example of a positioning unit) is a GPS receiving unit that performs positioning using radio waves received from GPS satellites, and is equipped with a flash memory 141. By storing predicted satellite orbit information (predicted ephemeris) in the flash memory 141, the GPS-IC14 can use this predicted ephemeris for a hot start and complete positioning in a short time. By storing the predicted ephemeris in the flash memory 141, and also storing valid position information, the GPS-IC14 can complete positioning in an even shorter time.

The short-range wireless communication unit 15 is a communication unit that transmits and receives various information to and from an external device, for example, the smartphone 2 described below, via a short-range wireless communication path such as Bluetooth (registered trademark) Low Energy. Since the smartphone 2 has a GPS positioning function, the CPU 11 can receive the location information, predicted ephemeris, and acquisition time acquired by the smartphone 2 via the short-range wireless communication unit 15. Note that the smartphone 2 may also have a means for acquiring location information other than the GPS positioning function. Furthermore, the short-range wireless communication unit 15 may receive location information acquired by a location information acquisition means other than the GPS positioning function.

FIG. 2 is a configuration diagram of the smartphone 2.
The smartphone 2 includes a CPU 21 , a display 22 , a memory 23 , a satellite radio wave receiving unit 24 , and a short-range wireless communication unit 25 .

The CPU 21 is a processing unit that controls each part of the smartphone 2. The display 22 is, for example, a touch panel display, and displays a graphical user interface for operating the smartphone 2. The memory 23 is, for example, a flash memory, and stores programs to be executed by the CPU 21. Note that the memory 23 is not limited to being composed of a flash memory.

The satellite radio wave receiving unit 24 is, for example, a GPS receiving unit that performs positioning using radio waves received from GPS satellites. The short-range wireless communication unit 25 transmits and receives information to and from the electronic watch 1 described above via a short-range wireless communication path such as Bluetooth (registered trademark) Low Energy. Note that the satellite radio wave receiving unit 24 does not have to receive radio waves from GPS satellites. A satellite positioning system other than GPS may be used as long as the same effect can be obtained.

About Predictive Ephemeris
The predicted ephemeris is predicted orbit information of satellites that is used to significantly extend the validity period of orbit information (ephemeris) required for positioning and to shorten the time it takes for the GPS receiving unit to determine position.

To determine position, the GPS receiver requires satellite orbital information (ephemeris). The GPS receiver acquires the ephemeris and uses it to determine position. At this time, the previously acquired ephemeris is backed up in memory, and by reading it out when determining position, positioning can be completed in a short time. This is called a hot start.
If the ephemeris is not backed up, it will have to be retrieved from the navigation message, which will take longer than a hot start. This type of operation is called a cold start.

Ephemeris has a validity period of about four hours, after which new ephemeris must be obtained. Therefore, the period during which a hot start, during which the GPS receiver can quickly determine positioning, is possible is usually about four hours from the time the previous ephemeris was obtained. If a device incorporating a GPS receiver (such as a GPS logger) is turned off for more than four hours, the next time it is turned on and positioning is performed again, a cold start is performed, which takes longer than a hot start.

Predicted ephemeris refers to orbital information that predicts and estimates the satellite position up to a specified time in the future based on the ephemeris received from the satellite and the device's position information (latitude and longitude). Predicted ephemeris makes it possible to achieve a hot start for a period of four hours or more after the ephemeris is acquired.

In addition, the GPS receiver performs internal calculations as necessary each time it receives new ephemeris, allowing the user to use the device without having to perform any tedious operations. At this time, the ephemeris received from the satellite must have been obtained within a specified time period, and the device's location information must not be far from the user's location.

The method of using the ephemeris and the most recent position information measured by the electronic watch 1 using GPS is effective in situations where the user always trains in the same place, and increases the probability of a hot start being achieved. However, when the user travels to a new location, for example on a business trip, the position information measured by the electronic watch 1 will be far from the user's location, and there is a risk that a hot start will not be possible.

On the other hand, the method in which the electronic watch 1 receives location information and ephemeris from an external device such as the smartphone 2 may satisfy the hot start requirements, since valid location information can be used at the destination as long as the smartphone 2 holds the location information. If the user sets the location information acquisition setting of the GPS application on the smartphone 2 to "always allow," the GPS application will periodically acquire location information. In this case, the smartphone 2 is likely to hold the user's most recent location information, and there is a high possibility that a hot start will be possible.

However, if the user has set the GPS application's location information acquisition setting to "Do not allow" or "Allow only when using the app," the smartphone 2 will be able to acquire location information from the GPS application less frequently, and so may not retain the most recent location information. In that case, the electronic watch 1 will more often than the smartphone 2 retain the user's most recent location information.

When the electronic watch 1 receives location information from the smartphone 2, it also receives the time information when the location information was obtained, and uses the newer location information (closer to the current time) compared to the previous positioning time. This process allows positioning to be performed using the most recent location information, making it easier to perform a hot start. This process is shown in Figure 3, which will be described later.

However, even if newer location information is adopted from among the location information held by the electronic watch 1 and the smartphone 2, it does not necessarily make it easier to perform a hot start. For example, if the location information measured by the smartphone 2 is location information of a destination far away from the place where the user usually trains, and if the user returns from the destination and performs the next location measurement at the place where the user usually trains, the location information measured by the smartphone 2 may be used. In this case, since the most recent location information held by the smartphone 2 is far away from the place where the user usually trains, there is a risk that a hot start cannot be performed. Therefore, in this case, it is better to use the new location information measured most recently by the electronic watch 1, which may hold the location information of the place where the user usually trains. In other words, even if the smartphone 2 has more recently acquired location information than the electronic watch 1, if a certain amount of time has passed since the location information was acquired, it is often better to use the location information measured most recently by the electronic watch 1. Therefore, when using location information measured by the smartphone 2, the time when the location information was acquired needs to be somewhat close to the current time. Therefore, in order to use the location information measured by the smartphone 2, a condition is added that "if the measurement time of the location information obtained from the smartphone 2 is within a predetermined time from the current time." This process is shown in FIG. 4, which will be described later.

However, if the "predetermined time" is made too short, it becomes difficult to use the location information determined by the smartphone 2 at the destination. For this reason, the "predetermined time" is set to a certain length, and the electronic watch 1 adds the condition "if a specified distance away" to the location information it plans to use at the next positioning, and determines the location information it plans to use at the next positioning. This increases the probability that the electronic watch 1 can use new location information most recently determined by the GPS receiver when performing regular training. Furthermore, if the user trains or races at a destination far away from where they usually train, the electronic watch 1 can increase the probability of shortening the time it takes to determine GPS positioning by using more effective location information determined by the smartphone 2.

3A and 3B are flowcharts showing the process in which the electronic timepiece 1 acquires location information and predicted ephemeris information from the smartphone 2.
<<Processing of Smartphone 2>>
The CPU 21 of the smartphone 2 executes an application for linking with the electronic watch 1, and receives the location information (latitude and longitude) acquired by the smartphone 2 and the time when that location was acquired from the smartphone 2 via communication using Bluetooth (registered trademark) Low Energy.
The CPU 21 of the smartphone 2 judges whether or not the condition for acquiring GPS information is satisfied after the start (S10). Here, the condition for acquiring GPS information is, for example, the setting of the GPS application of the smartphone 2. If the user sets the setting for acquiring location information of the GPS application to "not permitted", the condition for acquiring GPS information is not satisfied. If the user sets the setting for acquiring location information of the GPS application to "permit only when using the application", the condition for acquiring GPS information is satisfied when the GPS application is used. If the user sets the setting for acquiring location information of the GPS application on the smartphone 2 to "always permitted", the condition for acquiring GPS information is always satisfied. In addition, the condition is not limited to this, and for example, the elapsed time since the previous acquisition of GPS information can be a condition in addition to the setting of the GPS application.

In step S10, if the conditions for acquiring GPS information are met (Yes), the CPU 21 acquires position information and predicted ephemeris from satellite radio waves (S11) and proceeds to processing in step S12. If the conditions for acquiring GPS information are not met (No), the CPU 21 returns to processing in step S10. In step S11, the CPU 21 calculates predicted ephemeris, which is orbit information that predicts and estimates the satellite position up to a specified time in the future, based on the ephemeris received from the satellite and the device's position information (latitude and longitude).

In step S12, the CPU 21 determines whether the connection conditions with the electronic watch 1 are met. The connection conditions with the electronic watch 1 are met, for example, when the electronic watch 1 and the smartphone 2 are linked, when reconnecting from a link loss, when a time zone change notification is received from the smartphone 2 running an application, when the automatic time correction timing is achieved by Bluetooth (registered trademark) Low Energy, and when an application is started to link with the electronic watch 1 on the smartphone 2. As long as data can be received from the smartphone 2, the conditions are not limited to those mentioned above.

If the connection conditions with the electronic watch 1 are met (Yes), the CPU 21 transmits the acquired position information, acquisition time, and predicted ephemeris to the electronic watch 1 (S13), and then returns to the process of step S10. If the connection conditions with the electronic watch 1 are not met (No), the CPU 21 returns to the process of step S10. In this way, the CPU 21 of the smartphone 2 performs positioning by GPS and transmission of the measured position information, etc. under different conditions. Therefore, the acquisition time of the position information does not match the transmission time of the position information. Therefore, the CPU 21 transmits the acquisition time of this position information together with the transmission of the position information. Note that the method of obtaining the acquisition time of the position information is not limited. For example, the smartphone 2 may obtain the time by using radio waves received from a GPS satellite when performing positioning by GPS, or may obtain the time by using the time clocked by the CPU 21 of the smartphone 2. The time may also be obtained by combining the time clocked by the CPU 21 of the smartphone 2 and information obtained from the radio waves received from the GPS satellite.

<<Processing of Electronic Clock 1>>
The process in which the electronic watch 1 receives location information from the smartphone 2, as well as the acquisition time and predicted ephemeris of the location information acquired by the smartphone 2, will be described below. The flowcharts shown in Figures 3A, 3B, 4, and 5 below show the process when the CPU 11 executes a positioning control program stored in the memory 13. Note that the initial values of the "next GPS reception position use flag" and "smartphone position use flag" immediately after startup of the CPU 11 are OFF.

When the CPU 11 of the electronic watch 1 receives the position information, acquisition time, and predicted ephemeris transmitted in step S12 (S20), it determines whether the received position information is the first position information acquired since the electronic watch 1 was restarted (S21). Here, restart includes all clear (AC), which is the initialization of the software of the electronic watch 1, and battery all clear (BAC), which is a restart due to a drop in the power supply voltage. If the CPU 11 determines that the position information received in step S20 is the first position information acquired since the electronic watch 1 was restarted (AC) or battery all clear (BAC) (Yes), it proceeds to the processing of step S29 in FIG. 3B.

If the location information received in step S20 is not the first location information obtained since the electronic watch 1 was restarted or the battery was cleared (BAC) (No), the CPU 11 determines whether the "smartphone location use flag" (hereinafter, "smartphone location use flag") is ON (S22).

In step S22, if the "smartphone location use flag" is ON (Yes), the CPU 11 determines whether the time when the current location information was acquired by the smartphone 2 is newer than the time when the previous location information was acquired by the smartphone 2 (S24). This "smartphone location use flag" is a flag indicating that the location information received from the smartphone 2 is used for positioning. The time when the previous location information was acquired by the smartphone 2 is stored in the memory 13.
If the time at which the smartphone 2 currently acquires the location information is not closer to the current time than the time at which the smartphone 2 previously acquired the location information (No), the CPU 11 ends the processing in FIGS. 3A and 3B.
If the acquisition time of the current smartphone location information is newer than the acquisition time of the previous smartphone location information (Yes), the CPU 11 proceeds to the process of step S25 in FIG. 3B.

In step S22, if the "smartphone location use flag" is OFF (No), the CPU 11 determines whether the time when the current location information was acquired by the smartphone 2 is closer to the current time than the time when the previous GPS location information was acquired (S23). The time when the previous GPS location information was acquired is stored in the memory 13. Here, the previous GPS location information refers to the location information acquired by the electronic watch 1 at the time closest to the current time that is stored in the memory 13. In this embodiment, the memory 13 has location information obtained by positioning by the electronic watch 1 and location information received from the smartphone 2, so the location information acquired at the time closest to the current time among them is the previous GPS location information. Note that although the previous GPS location information is used, for example, if the smartphone 2 has a means for acquiring location information other than GPS, the time when the location information was acquired may be stored in the memory 13 and used as a comparison target.
If the time at which the smartphone 2 currently acquires the location information is not closer to the current time than the time at which the previous GPS location information was acquired (No), the CPU 11 ends the processing in FIGS. 3A and 3B.
If the acquisition time of the current smartphone position information is closer to the current time than the acquisition time of the previous GPS position information (Yes), the CPU 11 proceeds to the process of step S25 in FIG. 3B.

In step S25, the CPU 11 determines whether the time at which the current smartphone location information was acquired is within 24 hours from the current time. If the time at which the current smartphone location information was acquired is more than 24 hours from the current time (No), the CPU 11 ends the processing of Figures 3A and 3B. If the time at which the current smartphone 2 location information was acquired is within 24 hours (Yes), the CPU 11 proceeds to the processing of step S26, and calculates the distance between the previous location information and the current location information from the smartphone 2 from the previous location information and the current location information from the smartphone 2 (S26).

For example, if the smartphone 2 obtains location information while the user is on a business trip, and the electronic watch 1 uses the location of the smartphone 2 after the user returns home, the location information used for positioning will be far away from the user's current location. For this reason, a time limit as shown in step S25 is necessary. However, the time limit is not limited to 24 hours. For example, a time limit other than 24 hours may be set depending on the purpose of the device or the mode of the device.

In step S27, the CPU 21 determines whether the calculated distance exceeds 75 km. If the calculated distance does not exceed 75 km (No), the CPU 21 ends the processing of Figures 3A and 3B. If the calculated distance exceeds 75 km (Yes), the CPU 21 proceeds to the processing of step S28. The reason why the judgment condition in step S27 is 75 km is that the hot start condition of the GPS-IC 14 is within 75 km of the true value. However, the distance that serves as the judgment condition is not limited to 75 km. For example, a distance other than 75 km may be used as the judgment condition in accordance with the performance of the GPS-IC installed in the device.

In step S28, the CPU 11 turns on the "next GPS reception location use flag" and then turns on the "smartphone location use flag" (S29). The "next GPS reception location use flag" indicates that location information has been received since the device was restarted.

In this embodiment, the CPU 21 updates the location information from the smartphone 2 stored in the memory 13 with the location information currently acquired from the smartphone (S30), and updates the smartphone location acquisition time (S31). Note that it is not necessary to erase past location information data when updating, since the next time the electronic watch 1 measures its position, it is sufficient that the location information measured at the time closest to the current time is usable. Furthermore, the CPU 11 sets the predicted ephemeris in the flash memory 141 in the GPS-IC 14 (S32), and ends the processing of Figures 3A and 3B.

By processing the data in Figures 3A and 3B, the electronic watch 1 can input location information (latitude and longitude information) to the GPS-IC 14 before starting GPS reception, enabling a hot start in conjunction with the predicted ephemeris, significantly shortening the time it takes to complete positioning.

4 is a flowchart of a process for turning off the smartphone location use flag 24 hours after the time when the smartphone 2 determines its position. This process is executed, for example, every time the CPU 11 of the electronic watch 1 counts one hour, but is not limited to this and may be executed, for example, every 10 minutes.
In step S40, the CPU 11 determines whether the "next GPS reception position use flag" is ON. If the "next GPS reception position use flag" is OFF (No), the CPU 11 ends the process in FIG.

If the "next GPS reception position use flag" is ON (Yes), the CPU 11 proceeds to step S41 and determines whether the "smartphone position use flag" is ON. If the "smartphone position use flag" is OFF (No), the CPU 11 ends the process of FIG. 4.

If the "smartphone location use flag" is ON (Yes), the CPU 11 proceeds to step S42 and determines whether 24 hours have passed since the time when the smartphone 2 determined its position (location acquisition time). If it is within 24 hours since the time when the smartphone 2 obtained its position (No), the CPU 11 ends the process of FIG. 4.

If 24 hours have passed since the location of the smartphone 2 was acquired (Yes), the CPU 11 proceeds to step S43 and sets the "smartphone location use flag" to OFF (S43), and ends the process of FIG. 4.

In other words, in this embodiment, the validity period of the location information acquired by the smartphone 2 is 24 hours from the time the location information is acquired, so the CPU 11 turns off the "smartphone location use flag" when 24 hours have passed since the time the location information of the smartphone 2 was acquired.

Figures 5A and 5B are flowcharts of the GPS reception process by the electronic watch 1. This GPS reception process is started when the GPS-IC 14 receives radio waves from a GPS satellite, and executes a process (positioning operation) to obtain location information based on the satellite's radio wave information.

Between starting up the GPS-IC 14 and executing the received command, the CPU 11 writes hot start settings and location information (latitude and longitude information) into the execution parameter address map of the GPS-IC 14 according to the determination results shown in steps S52 and S53 of FIG. 5A.

At the beginning of the GPS reception process by the electronic watch 1, the CPU 11 starts the GPS-IC 14 (S50). If the flash memory 141 does not hold a valid predicted ephemeris (S51→No), the CPU 11 proceeds to the process of step S54 and does not send position information (latitude and longitude information) to the execution parameter map. This causes the GPS-IC 14 to perform a cold start. Cases where a valid predicted ephemeris is not held include immediately after the device is restarted or the battery is all cleared, and cases where the predicted ephemeris has expired after it was acquired. When step S54 is executed, a cold start is performed, so the time required for the GPS-IC 14 to determine the position is longer than the positioning in steps S55 to 57 described below.

In step S51, if the CPU 11 holds a valid predicted ephemeris (Yes), it proceeds to step S52 and determines whether the "next GPS reception position use flag" is ON.

If the "next GPS reception position use flag" is OFF (No), the CPU 11 proceeds to the process of step S57 and does not send position information (latitude and longitude information) to the execution parameter map. However, since a valid predicted ephemeris is held, the GPS-IC 14 can be hot started. Because it is a hot start, the time required for the GPS-IC 14 to perform positioning is shorter than in step S54. This allows the CPU 11 to complete positioning in a shorter time than the cold start setting in step S54. However, because positioning is performed without inputting position information (latitude and longitude information) to the execution parameter map, the time required for positioning is longer than in steps S55 and S56 described below.

If the "next GPS reception position use flag" is ON (Yes), the CPU 11 proceeds to the process of step S53 and determines whether the "smartphone position use flag" is ON.
If the "smartphone location use flag" is ON (Yes), the CPU 11 proceeds to the process of step S55 and transmits the location information (latitude and longitude information) measured by the smartphone 2 to the execution parameter map. This enables the GPS-IC 14 to be hot-started. This allows the CPU 11 to complete positioning in a shorter time than in the case of the hot start setting of step S57.

If the "smartphone location use flag" is ON in step S53 (Yes), the CPU 11 proceeds to the process of step S55 and inputs the latitude and longitude information measured by the smartphone 2 into the execution parameter map. This allows the GPS-IC 14 to be hot started. At this time, the time required for the GPS-IC 14 to measure the position is approximately several seconds. This allows the CPU 11 to complete the positioning in a shorter time than with the hot start setting in step S57.

Then, the GPS-IC 14 starts receiving GPS radio waves (S58), and the CPU 11 determines whether or not the GPS reception was successful (S59). If the GPS reception has failed (No), the CPU 11 ends the processing of Figs. 5A and 5B.

If the GPS-IC 14 is successful in receiving the GPS signal (Yes), the CPU 11 proceeds to step S60. The CPU 11 turns on the "next GPS reception location use flag" so that the acquired location information can be used the next time the signal is received (S60), and turns off the "smartphone location use flag" (S61). After that, the CPU 11 ends the GPS reception by the GPS-IC 14 (S62). In this embodiment, the GPS location information is updated with the location information acquired this time by the GPS-IC 14 (S63). Note that, since it is sufficient that the location information acquired at the time closest to the current time is available the next time the electronic watch 1 measures its position, it is not necessary to erase the data of the past location information when updating. When the process of step S63 ends, the process proceeds to step S64. Furthermore, the CPU 11 updates the acquisition time of the GPS location information (S64), and the processes of FIG. 5A and FIG. 5B end. Note that the method by which the CPU 11 acquires the acquisition time of the GPS location information is not limited. For example, time information may be obtained from GPS radio waves, or may be obtained using the time kept by the CPU 11. Time information may also be obtained by combining time information kept by the CPU 11 with information obtained from GPS radio waves.

(Modification)
The present invention is not limited to the above-described embodiment, and modifications can be made without departing from the spirit of the present invention. For example, the following modifications are possible:

(a) In the above embodiment, the electronic timepiece 1 downloads the predicted ephemeris together with the location information from the smartphone 2. However, this is not limited to the above, and the predicted ephemeris may be downloaded from the smartphone 2 under separate conditions.
(b) The present invention is not limited to the electronic watch 1 of the above embodiment, but may be applied to wearable devices in general.
(c) The external device that transmits location information and ephemeris to the electronic watch 1 is not limited to the smartphone 2, but may be any device with a GPS positioning function.
(d) The predicted ephemeris is not limited to being stored in a flash memory, but may be stored in a RAM (Random Access Memory) in the GPS-IC or in the memory 13.
(e) The communication method between the electronic watch 1 and the smartphone 2 is not limited to Bluetooth (registered trademark) Low Energy, and any wireless communication method such as Wi-Fi (registered trademark), ZigBee (registered trademark), or IrDA may be used.
(f) Within the scope of achieving the same effect, the flowcharts shown in Figures 3A to 5B may be modified in some respects. For example, the order of steps S25 to S27 shown in Figure 3B may be changed.

The inventions described in the claims originally attached to this application are listed below. The claim numbers in the appendix are the same as those in the claims originally attached to this application.

[Additional Notes]
<<Claim 1>>
a positioning unit that performs a positioning operation using radio waves received from a satellite and acquires first position information that is the position of the device itself and first time information that is the time when the position of the device itself is acquired;
a communication unit that communicates with an external device and receives second position information that is position information of the external device, orbital information related to the satellite, and second time information that is a time when the external device acquires the second position information;
A control unit that measures the current time;
a storage unit that stores the first location information, the first time information, the second location information, and the second time information;
A wearable device comprising:
When causing the positioning unit to perform a positioning operation, if the second time information stored in the memory unit is closer to the current time than the first time information stored in the memory unit, the position of the second position information stored in the memory unit is away from the position of the first position information stored in the memory unit by a predetermined distance or more, and the second time information stored in the memory unit is within a predetermined time from the current time, the control unit transmits the second position information and the trajectory information received from the external device to the positioning unit.
A wearable device characterized by:
<<Claim 2>>
The predetermined time is 24 hours.
The wearable device according to claim 1 .
<<Claim 3>>
The predetermined distance is 75 km.
3. The wearable device according to claim 1 or 2.
<<Claim 4>>
the positioning unit performs a cold start if the orbit information received from the external device is invalid, and performs a hot start using the orbit information if the orbit information is valid.
The wearable device according to any one of claims 1 to 3.
<Claim 5>
A step of performing a positioning operation by a positioning unit using radio waves received from a satellite, and acquiring first position information which is a position of the device itself and first time information which is a time when the position of the device itself is acquired;
a step of communicating with an external device by a communication unit and receiving second position information which is position information of the external device, orbital information related to the satellite, and second time information which is a time when the external device acquired the second position information;
A storage unit stores the first location information, the first time information, the second location information, and the second time information;
a step of transmitting the second position information and the trajectory information received from the external device to the positioning unit when the control unit causes the positioning unit to execute a positioning operation, if the second time information stored in the memory unit is closer to a current time than the first time information stored in the memory unit, the position of the second position information stored in the memory unit is away from the position of the first position information stored in the memory unit by a predetermined distance or more, and the second time information stored in the memory unit is within a predetermined time from the current time;
A positioning control method comprising the steps of:
<Claim 6>
On the computer,
A step of performing a positioning operation by a positioning unit using radio waves received from a satellite, and acquiring first position information which is a position of the device itself and first time information which is a time when the position of the device itself is acquired;
a step of communicating with an external device by a communication unit and receiving second position information which is position information of the external device, orbital information related to the satellite, and second time information which is a time when the external device acquired the second position information;
A storage unit stores the first location information, the first time information, the second location information, and the second time information;
a step of transmitting the second position information and the trajectory information received from the external device to the positioning unit when the second time information stored in the memory unit is closer to a current time than the first time information stored in the memory unit, the position of the second position information stored in the memory unit is away from the position of the first position information stored in the memory unit by a predetermined distance or more, and the second time information stored in the memory unit is within a predetermined time from the current time, when the positioning unit is caused to execute a positioning operation;
A positioning control program for executing the above.

1. Electronic watch (wearable device)
11 CPU (control unit)
12 Display 13 Memory (storage unit)
14 GPS-IC (positioning unit)
141 Flash memory 15 Short-range wireless communication unit (communication unit)
2 Smartphone (external device)
21 CPU
22 Display 23 Memory 24 Satellite radio wave receiving unit 25 Short-range wireless communication unit

Claims (8)

a positioning unit that performs a positioning operation using radio waves received from a satellite and acquires first position information that is the position of the device itself and first time information that is the time when the position of the device itself is acquired;
a communication unit that communicates with a portable external device and receives second position information, which is position information measured by the external device, orbital information related to the satellite, and second time information, which is a time when the external device acquires the second position information;
A control unit;
a storage unit that stores the first location information, the first time information, the second location information, and the second time information;
Equipped with
the control unit causes the positioning unit to perform a positioning operation using the second location information when the second time information stored in the storage unit is closer to a current time than the first time information stored in the storage unit and the second time information stored in the storage unit is within a predetermined time from the current time.
A wearable device characterized by: The predetermined time is 24 hours.
The wearable device according to claim 1 . the control unit, when a position of the second position information stored in the storage unit is away from a position of the first position information stored in the storage unit by a predetermined distance or more, causes the positioning unit to perform a positioning operation using the second position information;
The wearable device according to claim 1 . The predetermined distance is 75 km.
The wearable device according to claim 3 . the positioning unit performs a cold start if the orbit information received from the external device is invalid, and performs a hot start using the orbit information if the orbit information is valid.
The wearable device according to claim 1 . the control unit causes the positioning unit to perform a positioning operation using the second position information and the trajectory information received from the external device.
The wearable device according to claim 1 . Wearable computers,
causing a positioning unit to perform a positioning operation using radio waves received from a satellite, and to obtain first position information, which is the position of the device itself, and first time information, which is the time when the position of the device itself is obtained;
a step of causing a communication unit to communicate with a portable external device and receive second position information, which is position information measured by the external device, orbital information related to the satellite, and second time information, which is a time when the external device acquired the second position information;
storing the first location information, the first time information, the second location information, and the second time information in a storage unit;
causing the positioning unit to perform a positioning operation using the second location information when the second time information stored in the storage unit is closer to a current time than the first time information stored in the storage unit and the second time information stored in the storage unit is within a predetermined time from the current time;
A positioning control method comprising the steps of: For wearable device computers,
causing a positioning unit to perform a positioning operation using radio waves received from a satellite, and to obtain first position information, which is the position of the device itself, and first time information, which is the time when the position of the device itself is obtained;
a step of causing a communication unit to communicate with a portable external device and receive second position information, which is position information measured by the external device, orbital information related to the satellite, and second time information, which is a time when the external device acquired the second position information;
storing the first location information, the first time information, the second location information, and the second time information in a storage unit;
causing the positioning unit to perform a positioning operation using the second location information when the second time information stored in the storage unit is closer to a current time than the first time information stored in the storage unit and the second time information stored in the storage unit is within a predetermined time from the current time;
A positioning control program for executing the above.