JP2011043449A - Satellite signal receiver and method of controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a satellite signal receiver that improves reception sensitivity even by a small device and suppress an increase in power consumption, and to provide a method of controlling the same. <P>SOLUTION: A wrist watch 3 with a GPS includes a GPS antenna 27, an LNA 28 as a signal amplification means, a reception part 30, a time display unit 80, and a power supply unit 90. The reception part 30 includes a GPS signal processor 60 having a signal amplification means for controlling the LNA 28. The signal amplification control means outputs an OFF signal to a control signal input terminal when the reception mode is time measuring mode, to control the LNA 28 to keep halted. When the reception mode is positioning mode, the signal amplification control means outputs an ON signal to the control signal input terminal to control the LNA 28 to keep operated. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a satellite signal receiving apparatus that performs positioning and time correction based on a signal from a position information satellite such as a GPS satellite, and a control method for the satellite signal receiving apparatus.

As a GPS (Global Positioning System) receiving system, a GPS receiving apparatus having a built-in antenna connected to an external antenna incorporating a low noise amplifier (LNA) is known (see Patent Document 1).
The external antenna can improve the reception sensitivity as compared with the built-in antenna, but the power consumption increases in order to operate the LNA.
For this reason, in the GPS reception system of patent document 1, the power consumption was reduced by determining the positioning condition by a built-in antenna and selecting a built-in antenna when the positioning environment is good.

JP 2004-144676 A

In recent years, there has been proposed a small portable device such as a wristwatch or a cellular phone in which a GPS receiver is incorporated and position information and time information can be received. Connecting an external antenna as in Patent Document 1 to these small portable devices has a problem that it is difficult to apply because it impedes portability and increases power consumption.
Therefore, a wristwatch or the like is receiving only with a built-in antenna. For this reason, when the reception environment is bad, there is a problem that the reception sensitivity is lowered and it becomes impossible to receive GPS signals, and even if reception is possible, it takes a long time to complete reception.

  Moreover, it is preferable to use a battery as small as possible for a small portable device due to size restrictions, and a small battery such as a button type is often used. However, since a small battery has a small capacity, the life is shortened when the power consumption increases. In general, the longer the battery life is, the more the convenience can be improved. Therefore, it is necessary to reduce the power consumption and use the battery capacity effectively.

  An object of the present invention is to provide a satellite signal receiving apparatus and a control method for the satellite signal receiving apparatus that can improve the reception sensitivity even in a small device and can suppress an increase in power consumption.

  The satellite signal receiving apparatus of the present invention includes a receiving means for receiving a satellite signal transmitted from a position information satellite, a receiving control means for controlling the receiving means to perform a receiving process, and a receiving mode as a time measuring mode and a positioning mode. Receiving mode setting means that can be set to any one of the above, wherein the receiving means amplifies and outputs an input received signal in an operating state in which power is supplied, and is supplied with power. And a signal amplifying means for outputting the input received signal as it is in a stopped state, and the reception control means controls the signal amplifying means to the stopped state when the reception mode is set to the timekeeping mode. In addition, when the reception mode is set to the positioning mode, it has a signal amplification control means for controlling the signal amplification means to be in an operating state.

Here, the signal amplifying means is constituted by an LNA (Low Noise Amplifier) that amplifies the received satellite signal connected to the antenna.
The reception mode setting means can set the reception mode to either the time measurement mode or the positioning mode.
In the time measurement mode, for example, in the case of a GPS satellite signal, at least one satellite signal is received to obtain time information.
On the other hand, in the positioning mode, it is necessary to receive at least three satellite signals in order to obtain information necessary for calculating the current position of the satellite signal receiver. At this time, if there is even one satellite signal having a weak signal strength, it takes time to capture the satellite signal (satellite search time) and decoding processing of the captured signal, and power consumption increases.

According to the present invention, in the positioning mode, the signal amplifying means is operated to amplify the signal, whereby the satellite search time and the decoding processing time of the captured satellite signal can be shortened. Electric power can also be reduced.
In the timekeeping mode, even if the signal amplification means is stopped, a satellite signal with sufficient strength to obtain time information can usually be captured, so the signal amplification means is controlled to be stopped. is doing. Therefore, power consumption in the time measurement mode can be reduced.
Thus, since the signal amplification means is controlled according to the reception mode, the reception time can be shortened and efficient reception becomes possible. Therefore, limited power (battery capacity) can be used effectively, battery life can be extended, and the battery can be miniaturized.

  The satellite signal receiving apparatus of the present invention further comprises satellite signal search means for searching for the satellite signal by the receiving means, and the signal amplification control means is configured to perform the signal amplification during the satellite signal search processing by the satellite signal search means. It is preferable to control the means to a stop state.

According to the present invention, when the satellite signal search process is started by the satellite signal search means, the signal amplification means is controlled to be stopped by the signal amplification control means. For this reason, an increase in current consumption during the search process can be prevented.
A small portable device preferably uses a battery as small as possible due to size restrictions. In a small device, a small battery such as a button type is often used, but the battery size depends on a current value that the battery can flow. If the battery is used in excess of the current value that can flow, the battery will be greatly deteriorated. For this reason, in a small device, it is necessary to reduce the peak current value (the current value when the most current flows in the operation of the device).
In particular, a search process that requires a satellite signal acquisition process is a state in which a peak current with the highest current consumption flows in the reception process. For this reason, if the signal amplification means is further operated during the search process, the current consumption becomes higher. Therefore, the peak current in the satellite signal receiving device increases, and the battery size increases. In addition, since the power consumption increases, the battery life is shortened.
On the other hand, in the present invention, since the signal amplifying means is not operated during the search processing, the peak current can be reduced and the required battery size can be reduced, so that the satellite signal receiving apparatus can be miniaturized. Furthermore, power consumption can be reduced and battery life can be extended.

  In the satellite signal receiving apparatus of the present invention, the signal amplification control means, when the reception mode is set to the positioning mode, the signal amplification means only at a timing at which information necessary for positioning calculation is transmitted in the satellite signal. It is preferable to operate.

According to the present invention, when the signal amplifying means is operated when the reception mode is the positioning mode, the signal amplifying means is operated only at a timing at which time information and positioning information necessary for the positioning mode are transmitted. Can be reduced.
For example, in the case of a GPS satellite signal, one frame is composed of subframes 1 to 5, and transmission of each subframe takes 6 seconds. Therefore, transmission of one frame takes 30 seconds. Here, the information necessary for the positioning calculation is included in the subframes 1 to 3, and the subframes 4 and 5 do not need to be received. Therefore, if the signal amplifying means is activated only during 18 seconds during which subframes 1 to 3 are transmitted during reception of one frame (30 seconds), the signal amplifying means is activated even during transmission of subframes 4 and 5. Compared with the power consumption, the power consumption can be reduced.

  The satellite signal receiving apparatus of the present invention includes a receiving means for receiving a satellite signal transmitted from a position information satellite, a receiving control means for controlling the receiving means to perform a receiving process, and a receiving environment detecting means for detecting a receiving environment. The receiving means amplifies and outputs the input received signal in an operating state supplied with power, and outputs the input received signal as it is in a stopped state where power is not supplied. Signal amplification means, and the reception control means controls the signal amplification means to be in an operating state when it is determined that the reception environment is not good based on the detection value detected by the reception environment detection means. It is characterized by having.

The reception environment detection means detects information for determining the reception environment. As the reception environment, for example, whether the satellite signal receiving device is in an easily receivable place where the sky is open, for example, outdoors, or a place where the sky is not sufficiently open due to a wall or the like, such as indoors. Is mentioned. When the satellite signal receiving device is outdoors, there is a high possibility that the satellite signal receiving device can receive satellite signals from GPS satellites, and there is a high possibility of receiving GPS satellites located in the zenith direction. Since the satellite signal receiving device and the GPS satellite located in the zenith direction are short in distance, the possibility of receiving a satellite signal having a high signal strength is also increased.
On the other hand, if the satellite signal receiver is in a place where the sky is not sufficiently open, for example indoors, there are obstacles such as roofs and walls, so it is difficult to receive satellite signals from GPS satellites, For example, a satellite signal is received from a GPS satellite located in a direction with a small elevation angle through a building window. For this reason, the distance from the satellite receiver to the GPS satellite is increased, and the signal intensity is also decreased. Therefore, the reception time of the satellite signal becomes long and the power consumption increases.

According to the present invention, information for determining the reception environment is detected by the reception environment detection means, and the reception environment is determined based on the detected value. When it is determined that the reception environment is blocked by a wall or the like and the sky is not sufficiently open, for example, indoors, the signal amplification control means operates the signal amplification means to amplify the signal, thereby shortening the reception time. Power consumption can be reduced accordingly. As a result, limited power (battery capacity) can be used effectively, battery life can be extended, and the battery can be downsized.
In addition, it is preferable that the determination of the reception environment is performed at any time during the satellite signal reception process.

  The satellite signal receiving apparatus according to the present invention further comprises a reception mode setting means capable of setting a reception mode to any one of a time measurement mode and a positioning mode, wherein the reception mode is a positioning mode, and the reception environment detection means When it is determined that the reception environment is not good based on the detection value detected in step 1, the reception by the reception unit is preferably terminated.

If the reception environment is not good, the signal strength may be weak, and the reception time is likely to be long. In particular, when the reception mode is the positioning mode, it is necessary to receive at least three satellite signals. Therefore, there is a high possibility that the reception time will be longer than in the time measurement mode.
According to the present invention, since the reception operation is terminated in such a case, it is not necessary to continue the reception process in a poor reception environment, and power consumption can be suppressed.

  In the satellite signal receiving device of the present invention, the signal amplification control means operates the signal amplification means only at a timing at which time information is transmitted in the satellite signal when the reception mode is set to the timekeeping mode. When the reception mode is set to the positioning mode, it is preferable to operate the signal amplification means only at the timing at which information necessary for positioning calculation is transmitted in the satellite signal.

According to the present invention, when the signal amplifying means is operated when the reception mode is the positioning mode, the signal amplifying means is operated only at a timing at which time information and positioning information necessary for the positioning mode are transmitted. Can be reduced.
For example, in the case of a GPS satellite signal, one frame is composed of subframes 1 to 5, and transmission of each subframe takes 6 seconds. Therefore, transmission of one frame takes 30 seconds. Here, the information necessary for the positioning calculation is included in the subframes 1 to 3, and the subframes 4 and 5 do not need to be received. Therefore, if the signal amplifying means is activated only during 18 seconds during which subframes 1 to 3 are transmitted during reception of one frame (30 seconds), the signal amplifying means is activated even during transmission of subframes 4 and 5. Compared with the power consumption, the power consumption can be reduced.

In addition, when the reception mode is the timekeeping mode and the conditions for operating the signal amplifying means, the signal amplifying means is operated only when the time information necessary for the timekeeping mode is transmitted, thus reducing power consumption. it can.
For example, in the case of a GPS satellite signal, each subframe is transmitted at intervals of 6 seconds, and GPS time information (satellite time information) of a GPS satellite called TOW (Time of Week, also referred to as “Z count”) is transmitted in each subframe. Stored. Therefore, the time information is transmitted at intervals of 6 seconds, and the power consumption can be reduced by operating the signal amplification means only at the time of transmission.

  The satellite signal receiving apparatus of the present invention further comprises satellite signal search means for searching for the satellite signal by the receiving means, and the signal amplification control means is configured to perform the signal amplification during the satellite signal search processing by the satellite signal search means. It is preferable to control the means to a stop state.

  According to the present invention, when the satellite signal search process is started by the satellite signal search means, the signal amplification means is controlled to be stopped by the signal amplification control means. For this reason, an increase in current consumption during the search process can be prevented.

  In the satellite signal receiving apparatus of the present invention, the reception environment detection means includes energy detection means for detecting an amount of energy from the sun, and determines the reception environment based on a detection value detected by the energy detection means. Is preferred.

According to the present invention, the energy detection means is used as the reception environment detection means. The energy detection means detects an energy amount (illuminance) of light emitted from the sun and an ultraviolet ray amount. In general, the reception environment where the sky is open is easy, for example, the reception environment is good outdoors, and the sky is not sufficiently open due to a wall or the like, for example, the indoor environment is an environment where the reception environment is not good. By detecting this, the reception environment can be determined. As such an energy detecting means, any means capable of detecting the amount of light energy can be used. For example, a solar cell or an ultraviolet sensor can be used.
When a solar cell is used, the amount of energy from the sun can be detected, and when the amount of energy falls below a predetermined value (environment determination threshold), it can be determined that the room is indoor. In addition, if an ultraviolet ray sensor is used, the amount of ultraviolet rays from the sun can be detected, and if the amount of ultraviolet rays falls below a predetermined value (environmental judgment threshold), a place where the sky is not sufficiently opened due to a wall, etc. For example, it can be determined to be indoors.
In this way, the reception environment can be determined by setting the environment determination threshold according to the type of detected value to be detected and comparing the detection value with the environment determination threshold.

  In the satellite signal receiving apparatus of the present invention, the reception environment detecting means includes vibration detecting means for detecting a vibration state of the satellite signal receiving apparatus, and is determined to be in a vibration state based on a detection value detected by the vibration detecting means. It is preferable to determine that the reception environment is not good.

Here, the vibration of the satellite signal receiving device means a state where the satellite signal receiving device is not stationary. For example, vibration generated in the satellite signal receiving device when a wearer wearing a wristwatch equipped with the satellite signal receiving device is walking with his / her arm. In such a case, the positional relationship between the wristwatch (satellite signal receiving device) and the GPS satellite changes. For example, as the wristwatch moves, the building is positioned between the captured GPS satellite and the wristwatch. May not be able to receive satellite signals. For this reason, the intensity of the satellite signal also changes from time to time, and if the signal intensity becomes weak or cannot be received, the reception time becomes longer and the power consumption may increase.
As described above, when the satellite signal receiving apparatus vibrates, there is a high possibility that the reception environment is not good, and the vibration detecting means for detecting the vibration state of the satellite signal receiving apparatus functions as the receiving environment detecting means.

According to the present invention, the vibration state of the satellite signal receiving device is detected by the vibration detection means, and it is determined whether or not it is in the vibration state based on the detected value. If it is determined that it is in a vibration state, it can be determined that the reception environment is not good, so the signal amplification control means can shorten the reception time by operating the signal amplification means to amplify the signal. And power consumption can be reduced. As a result, limited power (battery capacity) can be used effectively, battery life can be extended, and the battery can be downsized.
In addition, it is preferable that the determination as to whether or not the vibration state is in this way is performed at any time during the satellite signal reception process.

Here, the determination of whether or not it is in a vibration state may be appropriately performed according to the detection method of the vibration state. For example, the case where an acceleration sensor, a gyro sensor, and a solar cell are used as vibration detection means will be described.
When the acceleration sensor is used, the acceleration when the satellite signal receiving apparatus vibrates (moves) is detected, and when the acceleration is equal to or greater than a predetermined value (vibration determination threshold), it can be determined that there is vibration. In addition, when a gyro sensor is used, an angle or angular velocity when the satellite signal receiving device moves can be detected, and when the angle or angular velocity is equal to or greater than a predetermined value (vibration determination threshold), it can be determined that there is vibration. Furthermore, when a solar cell is used, the amount of energy from the sun (such as illuminance) can be detected, and if the amount of change in the amount of energy within a certain time is greater than or equal to a predetermined value (vibration determination threshold), it can be determined that there is vibration .
As described above, it is possible to determine the presence or absence of vibration by setting the threshold value for vibration determination according to the type of detected value to be detected and comparing the detected value with the threshold value for vibration determination.

  A control method for a satellite signal receiving apparatus according to the present invention includes: a receiving unit having a signal amplifying unit for receiving a satellite signal transmitted from a position information satellite; and a receiving process by controlling the receiving unit. A satellite signal receiving device control method comprising: a reception control means for performing a reception control means, wherein the reception control means is capable of setting a reception mode to either a time measurement mode or a positioning mode; When the time measurement mode is set, the signal amplification means is controlled to be stopped, and when the reception mode is set to the positioning mode, the signal amplification means is controlled to be activated. .

According to the present invention, in the positioning mode, the signal amplifying means is operated to amplify the signal, whereby the satellite search time and the decoding processing time of the captured satellite signal can be shortened. Electric power can also be reduced.
In the timekeeping mode, a sufficiently strong satellite signal can be captured even if the signal amplifying means is stopped, so that the signal amplifying means is controlled to be stopped. Therefore, power consumption in the time measurement mode can be reduced.
Thus, since the signal amplification means is controlled according to the reception mode, the reception time can be shortened and efficient reception becomes possible. Therefore, limited power (battery capacity) can be used effectively, battery life can be extended, and the battery can be miniaturized.

  A control method for a satellite signal receiving apparatus according to the present invention includes: a receiving unit having a signal amplifying unit for receiving a satellite signal transmitted from a position information satellite; and a receiving process by controlling the receiving unit. And a reception environment detecting means for detecting a reception environment, wherein the reception control means uses the detection value detected by the reception environment detection means. When it is determined that the reception environment is good, the signal amplification means is controlled to be in a stopped state, and when it is determined that the reception environment is bad, the signal amplification means is controlled to be in an operating state.

  According to the present invention, information for determining the reception environment is detected by the reception environment detection means, and the reception environment is determined based on the detected value. When it is determined that the reception environment is not good, the signal amplification control means operates the signal amplification means to amplify the signal, thereby shortening the reception time and correspondingly reducing the power consumption. As a result, limited power (battery capacity) can be used effectively, battery life can be extended, and the battery can be downsized.

1 is a schematic plan view of a GPS wristwatch according to a first embodiment. It is a schematic sectional drawing of the wristwatch with GPS of 1st Embodiment. It is a block diagram which shows the circuit structure of the wristwatch with GPS of 1st Embodiment. It is a figure which shows the structure of a navigation message. It is a circuit diagram which shows the structure of LNA which is a signal amplification means. It is a block diagram which shows the structure of a GPS signal processing part. It is a block diagram which shows the structure of a control part. It is a flowchart which shows the reception processing procedure of 1st Embodiment. It is a graph which shows the change of the electric current value during reception processing. It is a graph which shows the acquisition rate of the satellite signal in each reception mode. It is a graph which shows the relationship between the reception time at the time of measurement, and signal strength. It is a graph which shows the relationship between the receiving time of positioning, and signal strength. It is a block diagram which shows the circuit structure of the wristwatch with GPS of 2nd Embodiment. It is a flowchart which shows the reception processing procedure of 2nd Embodiment. It is a graph which shows the acquisition rate of the satellite signal of 2nd Embodiment. It is a block diagram which shows the circuit structure of the wristwatch with GPS of 3rd Embodiment. It is a graph which shows the acquisition rate of the satellite signal in each environment of 3rd Embodiment. It is a flowchart which shows the reception processing procedure of 3rd Embodiment. It is a flowchart which shows the reception processing procedure of 4th Embodiment. It is a flowchart which shows the reception processing procedure of 5th Embodiment. It is a graph which shows the change of the electric current value during the reception process of 5th Embodiment. It is a block diagram which shows the circuit structure of the wristwatch with GPS of a modification.

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise stated, the present invention is not limited to these embodiments.

[First Embodiment]
1 and 2 are diagrams for explaining the structure of a GPS wristwatch 3 that is a satellite signal receiving apparatus according to the first embodiment. FIG. 1 is a schematic plan view of the GPS wristwatch 3, and FIG. 2 is a schematic sectional view of the GPS wristwatch 3 of FIG.

[Structure of GPS wristwatch]
As shown in FIG. 1, the GPS wristwatch 3 includes a dial 11 and a pointer 12. The pointer 12 includes a second hand, a minute hand, an hour hand, and the like, and is driven by a step motor via a gear.

  The GPS wristwatch 3 is configured to be able to perform reception mode setting, reception processing, and reception result display processing by manually operating the crown 14, the button 15, and the button 16.

  For example, in this embodiment, the reception mode (time measurement mode or positioning mode) is set by pressing the button 16. That is, every time the button 16 is pressed, the time measuring mode and the positioning mode are switched alternately. At this time, when the timekeeping mode is set, the second hand moves to the “Time” position (5 second position), and when the positioning mode is set, the second hand is set to the “Fix” position (10 second position). Therefore, the user can easily confirm the set reception mode.

When the button 15 is pressed for several seconds (for example, 3 seconds) or longer, the GPS wristwatch 3 performs reception processing.
Further, when the button 15 is pressed for a short time, the GPS wristwatch 3 displays the reception result in the immediately preceding reception mode by the dial 11 and the hands 12. For example, when the reception is successful in the timekeeping mode, the second hand moves to the “Time” position (5 second position), and when the reception is successful in the positioning mode, the second hand is at the “Fix” position (10 second position). ) In the case of reception failure, the second hand moves to the “N” position (20-second position).
These instructions by the second hand are also performed during reception. That is, the second hand moves to the “Time” position (5 second position) during reception in the timekeeping mode, and the second hand moves to the “Fix” position (10 second position) during reception in the positioning mode. When the GPS satellite cannot be captured, the second hand moves to the “N” position (20-second position).

As shown in FIG. 2, the GPS wristwatch 3 includes an outer case 17 made of a metal such as stainless steel (SUS) or titanium.
The exterior case 17 is formed in a substantially cylindrical shape, and a surface glass 19 is attached to the opening on the surface side via a bezel 18. The bezel 18 is made of a non-metallic material such as ceramic in order to improve satellite signal reception performance. A back cover 26 is attached to the opening on the back side of the exterior case 17.

  In the exterior case 17, a movement 13, a solar cell 22, a GPS antenna 27, a secondary battery 24, and the like are arranged.

The movement 13 includes a step motor and a train wheel 21. The step motor includes a motor coil 20, a stator, a rotor, and the like, and drives the pointer 12 via a train wheel 21.
A circuit board 25 is disposed on the back cover side of the movement 13, and the circuit board 25 is connected to the antenna substrate 23 and the secondary battery 24 via a connector 32.

  The circuit board 25 is provided with a receiving unit 30 including a receiving circuit that processes a satellite signal received by the GPS antenna 27, a control unit 40 that performs drive control of a step motor, and the like. The receiving unit 30 and the control unit 40 are covered with a shield plate 33 and are driven by electric power supplied from the secondary battery 24.

  The secondary battery 24 is a rechargeable secondary battery such as a lithium ion battery, and can store the power generated by the solar cell 22. That is, by electrically connecting the electrode of the solar cell 22 and the electrode of the secondary battery 24, the solar cell 22 performs photovoltaic power generation, and the secondary battery 24 is charged. In the present embodiment, a secondary battery such as a lithium ion battery is used as the secondary battery 24. However, the secondary battery 24 may be a power storage unit, and may be, for example, a capacitor.

  The solar cell 22 is disposed so as to face a part of the dial plate 11, receives light that has passed through the surface glass 19 and the dial plate 11, and performs photovoltaic power generation.

  Since the dial 11 is visible from the outside, it is desirable to improve the appearance while transmitting light as much as possible. Therefore, the dial 11 is made of a non-metallic material such as plastic or glass that transmits light.

  The GPS antenna 27 mounted on the antenna substrate 23 is an antenna that receives satellite signals from a plurality of GPS satellites, and is realized by a patch antenna, a helical antenna, a chip antenna, an inverted F antenna, or the like.

  In the present embodiment, the GPS antenna 27 is disposed on the back surface of the dial 11 in order to improve the decoration and wearability of the GPS wristwatch 3. Therefore, it is preferable that the dial 11 is made of a non-metal such as plastic or glass, which is a material that allows microwaves in the 1.5 GHz band to pass through, for example, a material having low conductivity and magnetic permeability.

The GPS antenna 27 receives microwaves (satellite signals) from the entire surface including the upper surface and side surfaces. Therefore, in this embodiment, the solar cell 22 is not disposed between the dial 11 and the GPS antenna 27 so that the metallic member in the solar cell 22 does not shield the microwave.
Further, as the distance between the GPS antenna 27 and the solar cell 22 is shorter, the GPS antenna 27 and the metallic member in the solar cell 22 are electrically coupled to cause loss. Furthermore, as the distance between the GPS antenna 27 and the solar cell 22 is shorter, the radiation pattern of the GPS antenna 27 is blocked by the solar cell 22 and the radiation pattern of the GPS antenna 27 becomes smaller. For this reason, in this embodiment, the distance between the GPS antenna 27 and the solar cell 22 is arranged to be equal to or greater than a predetermined value so that the reception performance does not deteriorate.

  Further, the GPS antenna 27 is arranged so that the distance from the metal member other than the solar cell 22 is also a predetermined value or more. For example, when the exterior case 17 and the movement 13 are made of a metal member, the GPS antenna 27 is arranged such that both the distance to the exterior case 17 and the distance to the movement 13 are equal to or greater than a predetermined value.

[Circuit configuration of GPS wristwatch]
The GPS wristwatch 3 receives a satellite signal from at least one GPS satellite (positional information satellite), acquires GPS time information, and corrects the internal time information based on the GPS time information; It is set to one of the positioning modes that receive satellite signals from multiple GPS satellites, perform positioning calculation to find the current location, and correct the internal time information based on the time difference specified from the current location and the GPS time information . That is, the GPS wristwatch 3 performs either a time correction process in the time measurement mode or a time correction process (time difference correction process) in the positioning mode.

[GPS system]
Before describing the circuit configuration of FIG. 3 in detail, an outline of a GPS system that is a communication system using microwaves will be described.
The GPS satellite orbits in a predetermined orbit above the earth and transmits a navigation message superimposed on a 1.57542 GHz microwave (Ll wave) to the ground. Here, the GPS satellite is an example of the position information satellite in the present invention, and the 1.57542 GHz microwave (hereinafter referred to as “satellite signal”) on which the navigation message is superimposed is an example of the satellite signal in the present invention.

  At present, there are about 30 GPS satellites, and in order to identify which GPS satellite the satellite signal is transmitted from, each GPS satellite has 1023 chips (Coarse / Acquisition Code) called 1023 chips (1 ms period) ) Is superimposed on the satellite signal. The C / A code looks like a random pattern with each chip being either +1 or -1. Therefore, by correlating the satellite signal and the pattern of each C / A code, the C / A code superimposed on the satellite signal can be detected.

  The GPS satellite has an atomic clock, and the satellite signal includes extremely accurate time information (hereinafter referred to as “GPS time information”) timed by the atomic clock. Further, a slight time error of an atomic clock mounted on each GPS satellite is measured by a control segment on the ground, and the satellite signal includes a time correction parameter for correcting the time error. Therefore, a satellite signal receiver (hereinafter referred to as “GPS receiver”) built in the GPS wristwatch 3 receives a satellite signal transmitted from one GPS satellite, and includes GPS time information and time contained therein. The correction time can be used to correct the internal time to the correct time.

The satellite signal also includes orbit information indicating the position of the GPS satellite in the orbit. The GPS receiver can perform positioning calculation using GPS time information and orbit information. The positioning calculation is performed on the assumption that a certain amount of error is included in the internal time of the GPS receiver. That is, in addition to the x, y, and z parameters for specifying the three-dimensional position of the GPS receiver, the time error becomes an unknown. Therefore, a GPS receiver generally receives satellite signals transmitted from four or more GPS satellites, and performs three-dimensional positioning calculation using GPS time information and orbit information included therein.
However, when only three satellite signals can be received, the altitude (z) is set to 0 m or the like, and two-dimensional positioning for obtaining x and y is performed, so that the approximate two-dimensional position (latitude, Longitude) can be specified. Since the position detection of this embodiment is for acquiring time difference information, even if position data is acquired by two-dimensional positioning, normally correct time difference information can be acquired.

[Navigation message]
FIG. 4A to FIG. 4C are diagrams for explaining the configuration of the navigation message superimposed on the satellite signal.
As shown in FIG. 4A, the navigation message is configured as data with a main frame of 1500 bits as a unit. The main frame is divided into five sub-frames 1 to 5 each having 300 bits. One subframe of data is transmitted in 6 seconds from each GPS satellite. Accordingly, data of one main frame is transmitted from each GPS satellite in 30 seconds.

  Subframe 1 includes satellite correction data such as week number data. The week number data is information representing a week including the current GPS time information. The starting point of the GPS time information is January 6, 1980, 00:00:00 in UTC (Coordinated Universal Time), and the week starting on this day is the week number 0. Week number data is updated on a weekly basis.

  Subframes 2 and 3 include ephemeris parameters (detailed orbit information of each GPS satellite). The subframes 4 and 5 include almanac parameters (general orbit information of all GPS satellites).

  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 GPS satellites at intervals of 6 seconds, whereas satellite correction data such as week number data, ephemeris parameters, and almanac parameters are transmitted at intervals of 30 seconds.

  As shown in FIG. 4B, the TLM word includes preamble data, a TLM message, a reserved bit, and parity data.

  As shown in FIG. 4C, 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. For example, the Z count data of subframe 1 indicates GPS time information at which the first bit of subframe 2 is transmitted. The HOW word also includes 3-bit data (ID code) indicating the ID of the subframe. That is, ID codes “001”, “010”, “011”, “100”, and “101” are included in the HOW words of subframes 1 to 5 shown in FIG.

  The GPS receiver can acquire GPS 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 GPS receiver has previously acquired the week number data and is counting the elapsed time from the time when the week number data was acquired internally, the current GPS satellites can be acquired without acquiring the week number data. Week number data can be obtained. Therefore, the GPS receiver can know the current time other than the date by acquiring the Z count data. For this reason, the GPS receiver normally acquires only the Z count data as the current time.

Next, the circuit configuration of the GPS wristwatch 3 incorporating such a GPS receiver will be described in detail. FIG. 3 is a block diagram illustrating a circuit configuration of the GPS wristwatch 3 according to the first embodiment.
The GPS wristwatch 3 includes a GPS antenna 27, an LNA 28 as signal amplification means, a receiver 30, a time display device 80, and a power supply device 90.

[GPS antenna]
The GPS antenna 27 is an antenna that receives satellite signals from a plurality of GPS satellites, and is configured by a patch antenna or the like as described above. The output of the GPS antenna 27 is connected to the LNA 28.

[LNA]
As shown in FIG. 5, the LNA 28 includes an input terminal 281, an output terminal 282, an operational amplifier 283, a power switch 284, an output changeover switch 285, and a control signal input terminal 286 that controls the switches 284 and 285.
The input terminal 281 is connected to the signal input side of the LNA 28, that is, the GPS antenna 27 side, and receives a satellite signal received by the GPS antenna 27.
The output terminal 282 is connected to the signal output side of the LNA 28, that is, the receiving unit 30, and outputs a satellite signal amplified by the operational amplifier 283 or a satellite signal that has passed through the operational amplifier 283, as will be described later.

The operational amplifier 283 is connected to a positive power supply VDD and a negative power supply VSS. The positive power supply VDD is connected to the operational amplifier 283 via the power switch 284.
The power switch 284 selectively connects the positive power supply VDD to either the a terminal connected to the operational amplifier 283 or the b terminal not connected to either.
The output changeover switch 285 supplies either the amplification output terminal c, which is the output of the operational amplifier 283, or the through output terminal d, which outputs a signal input from the input terminal 281 without passing through the operational amplifier 283, to the output terminal. 282 is connected.

  In the LNA 28, when an ON signal (for example, a high level signal) is input to the control signal input terminal 286, the power switch 284 is connected to the a terminal, and the output changeover switch 285 is connected to the amplified output terminal c. Therefore, the operational amplifier 283, that is, the LNA 28 is operated with the positive power supply VDD connected thereto. The satellite signal input from the input terminal 281 is amplified by the operational amplifier 283 and output from the output terminal 282 via the amplification output terminal c and the output changeover switch 285.

  On the other hand, when an off signal (for example, a low level signal) is input to the control signal input terminal 286, the power switch 284 is connected to the b terminal and the output changeover switch 285 is connected to the through output terminal d. For this reason, the operational amplifier 283, that is, the LNA 28 is disconnected from the positive power supply VDD and brought into a stopped state. The satellite signal input from the input terminal 281 is output from the output terminal 282 via the through output terminal d and the output changeover switch 285 without passing through the operational amplifier 283.

[Receiver]
The receiving unit 30 mainly includes an RF (Radio Frequency) unit 50 and a GPS signal processing unit 60. The RF unit 50 and the GPS signal processing unit 60 perform processing for acquiring satellite information such as orbit information and GPS time information included in the navigation message from the satellite signal in the 1.5 GHz band. The receiving unit 30 of this embodiment includes an 8-channel receiving circuit so that eight satellite signals can be simultaneously captured and received.

[RF part]
The RF unit 50 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. is there.

[GPS signal processor]
Although not shown, the GPS signal processing unit 60 includes a DSP (Digital Signal Processor), a CPU (Central Processing Unit), an SRAM (Static Random Access Memory), an RTC (Real Time Clock), and the like, and is output from the RF unit 50. The baseband signal is demodulated from the digital signal (intermediate frequency band signal).
The GPS signal processing unit 60 includes various units that function by executing a predetermined program with a built-in CPU. Specifically, as shown in FIG. 6, the satellite signal search means 61 for executing the satellite signal search process, the signal amplification control means 62 for executing the signal amplification control process, and the reception mode at the receiver 30 are measured. The receiving mode setting means 63 for setting the mode or the positioning mode, and the signal decoding means 64 for decoding the received satellite signal and acquiring information are provided.

The satellite signal search means 61 generates a local code having the same pattern as each C / A code in the satellite signal search process described later, and correlates each C / A code included in the baseband signal with the local code. I do. Then, the satellite signal search means 61 adjusts the local code generation timing so that the correlation value for each local code has a peak, and if the correlation value is equal to or greater than the threshold value, it synchronizes with the GPS satellite of the local code (that is, , GPS satellite is captured).
Here, the GPS system employs a CDMA (Code Division Multiple Access) system in which all GPS satellites transmit satellite signals of the same frequency using different C / A codes. Accordingly, it is possible to search for GPS satellites that can be captured by determining the C / A code included in the received satellite signal.

The signal amplification control means 62 controls the operation of the LNA 28 by outputting a control signal to the control signal input terminal 286 of the LNA 28 according to the currently set reception mode.
Specifically, when the reception mode is the timekeeping mode, the signal amplification control means 62 outputs an off signal to the control signal input terminal 286, and controls the LNA 28 to be stopped. On the other hand, when the reception mode is the positioning mode, the signal amplification control means 62 outputs an ON signal to the control signal input terminal 286, and controls the LNA 28 to be in an operating state.

The reception mode setting unit 63 controls the operation of the reception unit 30 according to the reception mode.
The signal decoding means 64 mixes a local code having the same pattern as the C / A code of the captured GPS satellite and a baseband signal, demodulates the navigation message, and satellites such as orbit information and GPS time information included in the navigation message. Get information.

  The trajectory information and GPS time information included in the navigation message are examples of position information (positioning data) and time information (time data) in the present invention. Then, the GPS signal processing unit 60 outputs the acquired time data and positioning data to the control unit 40 of the time display device 80.

In the present embodiment as described above, the receiving means of the present invention is configured by various configurations that perform reception processing in the GPS antenna 27, the LNA 28, and the receiving unit 30.
The satellite signal search means 61, the signal amplification control means 62, the reception mode setting means 63, the signal decoding means 64, etc. of the GPS signal processing unit 60 constitute the reception control means of the present invention.
Note that the reception control means of the present invention is not limited to the one configured by the GPS signal processing unit 60, and may be configured by the control unit 40. For example, the control unit 40 may acquire information such as a signal level from the GPS signal processing unit 60 and control the LNA 28. That is, the satellite signal search means, the signal amplification control means, the reception mode setting means, the signal decoding means, etc. that perform the satellite search processing and signal amplification control by controlling the receiving section 30 are configured by the GPS signal processing section 60. Alternatively, the control unit 40 may be used, and both the control unit 40 and the GPS signal processing unit 60 may be used.

[Configuration of time display device]
The time display device 80 includes the control unit 40 and the hands 12.
As shown in FIG. 7, the control unit 40 includes a storage unit 41, an oscillation circuit 42, and a drive circuit 43, and performs various controls.
The control unit 40 controls the receiving unit 30. That is, the control unit 40 sends a control signal to the receiving unit 30 when the receiving operation is performed by keeping the button 15 pressed or when the receiving time is set in advance, and the receiving unit 30 30 reception operations are controlled. Further, the driving of the hands 12 is controlled via the drive circuit 43 in the control unit 40.

  The storage unit 41 stores internal time information and a reception mode. The internal time information is time information measured inside the GPS wristwatch 3. The internal time information is updated by the reference clock signal generated by the oscillation circuit 42. Therefore, even if the power supply to the receiving unit 30 is stopped, the internal time information can be updated and the hand movement of the hands 12 can be continued. The reception mode is updated to either the time measurement mode or the positioning mode every time the button 16 is operated.

When the reception mode is set to the timekeeping mode, the control unit 40 controls the operation of the reception unit 30 to acquire GPS time information, corrects the internal time information based on the GPS time information, and stores the storage unit. 41. More specifically, the internal time information is UTC (Coordinated Universal Time) obtained by subtracting the accumulated leap seconds (currently 15 seconds) inserted after January 6, 1980 from the acquired GPS time information. To be corrected. Further, when time difference data is stored in the storage unit 41, the time difference data is also added, corrected to time information of the current location, and stored in the storage unit 41.
In addition, when the reception mode is set to the positioning mode, the control unit 40 controls the operation of the reception unit 30 to acquire GPS time information and positioning data, and from the GPS time information and the leap second accumulation and the current location. Based on the required time difference data, the internal time information is corrected and stored in the storage unit 41. Note that data representing the correspondence between the positioning data and the time difference data is stored in the storage unit 41 in advance.

[Power supply device]
The power supply device 90 includes the solar cell 22 and the secondary battery 24.
The current generated by the photovoltaic power generation of the solar cell 22 is supplied to the secondary battery 24, and the secondary battery 24 is charged.
The secondary battery 24 supplies driving power to the LNA 28, the receiving unit 30, the time display device 80, and the like.

[Receive processing]
Next, the procedure of reception processing in the GPS wristwatch 3 of the first embodiment will be described with reference to FIG.
The control unit 40 of the GPS wristwatch 3 sends a control signal to the GPS signal processing unit 60 when the regular reception time is reached or when the button 15 is pressed for a certain time and the reception operation is performed manually. The GPS signal processing unit 60 performs reception processing. That is, the receiving unit 30 is activated by a control signal from the control unit 40. First, the signal amplification control means 62 controls the LNA 28 in accordance with the reception mode (step 1, hereinafter “step” is abbreviated as “S”). Specifically, when the reception mode is the positioning mode, an ON signal is output to the control signal input terminal 286 of the LNA 28, and the LNA 28 is controlled to be in an operating state. When the reception mode is the timekeeping mode, the signal amplification control means 62 outputs an off signal to the control signal input terminal 286 of the LNA 28, and controls the LNA 28 to be stopped.
And the receiving part 30 starts reception of the satellite signal transmitted from a GPS satellite (S2).

Next, the satellite signal search means 61 of the GPS signal processing unit 60 starts a satellite signal search process (satellite search process) (S3). In the satellite search step, the receiving unit 30 performs a process of searching for a GPS satellite that can be captured.
Specifically, for example, when there are 30 GPS satellites, first, the satellite signal search means 61 changes the satellite number SV from 1 to 30 in sequence and has the same pattern as the C / A code of the satellite number SV. Generate local code. Next, the satellite signal search means 61 calculates the correlation value between the C / A code and the local code included in the baseband signal. If the C / A code and the local code included in the baseband signal are the same code, the correlation value has a peak at a predetermined timing, but if the code is different, the correlation value does not have a peak and is always almost zero.

The satellite signal search means 61 adjusts the local code generation timing so that the correlation value between the C / A code and the local code included in the baseband signal is maximized, and when the correlation value is equal to or greater than a predetermined threshold value. It is determined that the GPS satellite having the satellite number SV is captured. At this time, only GPS satellites whose satellite signal strength (SNR) is equal to or higher than a predetermined level are to be captured.
And the satellite signal search means 61 memorize | stores the information (for example, satellite number) of each captured GPS satellite.

The code length of the local code is 1 ms, and even if the search process of about 30 GPS satellites is performed while adjusting the local code generation timing, the search for all GPS satellites can be completed in about 2 seconds. Can do.
In the present embodiment, the search process of about 30 GPS satellites is repeatedly executed a predetermined number of times, for example, three times in the satellite search step S3.

By the way, as shown in FIG. 9, at the time of satellite search in the positioning mode, the current for operating the RF unit 50, the current for performing the satellite search process in the GPS signal processing unit 60, and the LNA 28 are operated. It is necessary to pass the current. As described above, the GPS signal processing unit 60 needs to generate a local code, calculate a correlation value, and the like during the satellite search process. For this reason, the current consumption value in the GPS signal processing unit 60 also increases, and the current value at the time of satellite search becomes the peak current in the GPS wristwatch 3.
As an example, the current value of the RF unit 50 at the time of satellite search is about 10 mA, the current value of the GPS signal processing unit 60 is about 15 mA, and the current value of the LNA 28 is about 2 mA. Although a current of about 1 μA always flows through the control unit 40, it is not shown in FIG. 9 because it is smaller than the current values of the RF unit 50, the GPS signal processing unit 60, and the LNA 28.

  Here, in the positioning mode, since the LNA 28 is in the operating state, the operating current of the LNA 28 is added to the current consumption during the satellite search. In the timekeeping mode, since the LNA 28 is in a stopped state, the current of the LNA 28 is not added. Accordingly, the size and the like of the secondary battery 24 may be set based on the current consumption during the satellite search in the positioning mode. For example, in the above example, about 10 mA + about 15 mA + about 2 mA + about 1 μA = about 27 mA is the peak current value, so the secondary battery 24 that can output the current value may be used.

  Next, the satellite signal search means 61 determines whether or not a predetermined number of satellites have been captured in the satellite search step S3 (S4). Here, the predetermined number of satellites is at least one satellite when the reception mode is set to the timekeeping mode, and at least three satellites when the reception mode is set to the positioning mode. It is a satellite.

  If the satellite signal search means 61 determines “No” in S4, the satellite search step S3 continues.

On the other hand, if “YES” is determined in S4, the signal decoding means 64 of the GPS signal processing unit 60 performs a decoding process on the received satellite signal (S5).
At the time of this decoding process, as shown in FIG. 9, the current consumption value of the GPS signal processing unit 60 is significantly reduced compared to the time of satellite search. For this reason, the current value during the decoding process is smaller than the peak current during the satellite search.
For example, the current value of the RF unit 50 at the time of satellite signal decoding is about 10 mA, the current value of the GPS signal processing unit 60 is about 5 mA, and the current value of the LNA 28 is about 2 mA. Therefore, while the current value at the time of satellite search is about 27 mA, the current value at the time of satellite signal decoding is reduced to about 17 mA.

The current value at the time of satellite search of the satellite signal in FIG. 9 is a value when satellite search processing is performed for all eight channels, and the current value at the time of satellite signal decoding ends the satellite search processing, and the decoding processing is performed. It is a value when only doing.
As an operation to end the search process, all eight channels of satellite signals are captured, and when all channels shift to decoding, or when a predetermined number of channels of satellite signals are captured, search processing of other channels is performed. Sometimes it stops.
On the other hand, depending on the method of the correlator of the GPS signal processing unit 60, for example, the satellite search process is continued in the other channels while acquiring 1 to 3 satellite signals and performing the satellite signal decoding process. You can also. Even in this case, since the current value that is increased when the LNA 28 is operated is smaller than the current value that is decreased when the satellite is captured by one channel and the process proceeds to the decoding process, the satellite search process and the decoding process are performed. Even if the LNA 28 is operated at the same time, the current value becomes smaller than the peak current value when the satellite search processing is performed in all eight channels.

The signal decoding means 64 determines whether or not predetermined data has been acquired within a preset time (within a timeout time) (S6).
Here, the set time (timeout time) for determining the data acquisition time is set according to the reception mode. That is, since the positioning mode requires more time for signal reception processing and decoding processing than the time measurement mode, the set time may be set longer.
For example, the timeout time is set as the time from the start of reception to the end of reception, the timeout time in the timekeeping mode is set in the range of, for example, 20 to 60 seconds, and the timeout time in the positioning mode is, for example, 60 to 180 seconds. It is set in the range.

If the GPS signal processing unit 60 determines “Yes” in S <b> 6, the GPS signal processing unit 60 ends the reception process (S <b> 7).
The GPS signal processing unit 60 outputs the received time data to the control unit 40 in the timekeeping mode, and outputs the received time data and positioning data to the control unit 40 in the positioning mode.
In the time measurement mode, the control unit 40 corrects the internal time based on the time data, and also corrects the indication time of the pointer 12. In addition, the control part 40 corrects the time data (GPS time information) which can be acquired with a GPS signal with the time difference data of the present location acquired in advance, and acquires the time information of the present location. Then, the control unit 40 corrects the internal time information being timed with the current time information, controls the driving circuit 43 of the hands 12 based on the corrected internal time information, and corrects the time display ( S8).

On the other hand, in the positioning mode, the control unit 40 acquires time difference data from a correspondence table of position data and time difference data stored in advance. And the control part 40 corrects the time data (GPS time information) which can be acquired with a GPS signal with the acquired said time difference data, and acquires the time information of the present location. Then, the control unit 40 corrects the internal time information being timed with the current time information, controls the driving circuit 43 of the hands 12 based on the corrected internal time information, and corrects the time display ( S8).
Thus, the control unit 40 and the GPS signal processing unit 60 end the reception process.

  In addition, when it is determined “No” in S6, the GPS signal processing unit 60 ends the reception process without correcting the time (S9).

Here, an experiment on the signal strength in each reception mode was performed. The experimental results are shown in FIGS.
FIG. 10 shows the satellite signal acquisition rate in each reception mode. Wear GPS watch 3 at a certain location (in front of Shinjuku station, open the sky near the zenith, and block the building with a low elevation angle) and receive it multiple times in a stationary state and measure its acquisition rate It is a thing. The timeout of the reception time is 1 minute in the timekeeping mode and 3 minutes in the positioning mode. The acquisition rate (%) can be calculated by the following formula.

  Acquisition rate (%) = number of successful receptions / number of receptions × 100

According to FIG. 10, in the time measurement mode, the acquisition rate is 100% regardless of whether or not the LNA is activated. On the other hand, in the positioning mode, the acquisition rate is 60% when the LNA is stopped (off), but when the LNA is activated (on), the acquisition rate is improved to 100%.
In order to perform positioning in the positioning mode, three or more satellites are required. If there is even one satellite with low signal strength, the reception time becomes long, and reception may not be possible within the time-out time. Therefore, by increasing the reception strength by operating (turning on) the LNA, the reception time is shortened, and reception can be completed within the timeout time. On the other hand, in the timekeeping mode, if there is even one satellite with high signal strength, it can be reliably received, so the acquisition rate is 100% even when the LNA is stopped (off).

Further, when the relationship between the reception time and the signal strength in the time measurement mode was tested, the relationship shown in FIG. 11 was obtained. That is, the reception time tends to increase as the signal strength decreases. When the signal strength is -134 dBm, it can be seen that the signal can be received in 15 seconds.
On the other hand, the relationship between the reception time and the signal strength in the positioning mode is as shown in FIG. 12, and when the signal strength is -134 dBm, the reception time is 35 seconds, which is compared with the time measurement mode. Will become longer. Here, if the timeout is set to 35 seconds, the signal strength needs to be −134 dBm or more in order to receive within the timeout. When the signal strength is less than -134 dBm, the reception time can be shortened by increasing the reception strength by setting the LNA 28 in an activated (ON) state. For example, when the signal strength is -136 dBm, the reception time is about 65 seconds on average, but by operating an LNA (here, an LNA capable of amplifying 2 dBm), the reception strength is -134 dBm. Thus, reception is possible with a reception time of 35 seconds.

  In addition to the operational amplifier 283, the LNA 28 of this embodiment can output through the operational amplifier 283 when the power is turned off by providing the switches 284, 285, the through output terminal d, and the like. These switching controls can be easily controlled because the switches 284 and 285 operate in conjunction with each other only by inputting a control signal to the control signal input terminal 286.

[Effects of First Embodiment]
According to the present embodiment, the signal amplification control means 62 controls the LNA 28 according to the set reception mode. That is, the LNA 28 is stopped in the time measurement mode, and the LNA 28 is operated in the positioning mode.
For this reason, in a positioning mode that requires three or more satellites with high signal strength, a satellite signal with low signal strength can be amplified, and the reception time can be shortened. As a result, power consumption can be reduced, and efficient reception becomes possible.

In the present embodiment, the LNA 28 is normally stopped in the timekeeping mode that does not require signal amplification, so that an increase in power consumption in the timekeeping mode can be prevented.
In particular, the GPS wristwatch 3 usually only needs to be able to acquire time information, and therefore reception in the timekeeping mode is more frequent than reception in the positioning mode. For example, scheduled reception such as once a day is executed in a timekeeping mode. On the other hand, the reception in the positioning mode is, for example, at the time of the first reception after moving to an area with a different time zone due to travel or the like, and the frequency is low.
In the present embodiment, the power consumption can be effectively reduced because the LNA 28 is stopped in the timekeeping mode with a high execution frequency.
As described above, limited power (battery capacity) can be used effectively, battery life can be extended, and the battery can be downsized. Therefore, the GPS wristwatch 3 in which the GPS receiver is incorporated can be downsized.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The configuration of the GPS wristwatch 3 according to the second embodiment is different from that of the first embodiment in that it includes a vibration detection unit 70 as reception environment detection means. The description of the same configuration as that of the first embodiment is omitted.

[Circuit Configuration of Second Embodiment]
As shown in FIG. 13, the GPS wristwatch 3 includes a vibration detection unit 70 in addition to the configuration of the first embodiment.
The vibration detection unit 70 detects the vibration state of the GPS wristwatch 3 and outputs the detected value to the control unit 40 as a detection signal. Here, the vibration means a state where the GPS wristwatch 3 is not stationary.
In the present embodiment, the on / off state of the LNA 28 is controlled by the vibration state, that is, whether or not the GPS wristwatch 3 is stationary. If the GPS wristwatch 3 is not stationary, the satellite signal This is because the possibility that the strength is lowered is high.
For example, when the user wearing the GPS wristwatch 3 is walking, the positional relationship between the GPS wristwatch 3 and the GPS satellite changes sequentially. Usually, the GPS antenna 27 of the GPS wristwatch 3 has directivity, and if the arm is swung while walking, the direction of the antenna 27 with respect to the GPS satellite also changes, and the signal strength of the captured satellite signal decreases, There is a possibility that it cannot be received. Therefore, in such a case, if the received signal is amplified by operating the LNA 28, the period for securing the signal strength necessary for search and decoding is increased compared with the case where the LNA 28 is stopped. The rate can be improved.
Here, the measurement when the GPS wristwatch 3 of the second embodiment is worn and walking in a certain place (in front of Shinjuku Station, the sky near the zenith is open and the place where the elevation angle is low is obstructed by buildings such as buildings) is measured. An example of the satellite signal acquisition rate in the hour mode is shown in FIG. According to FIG. 15, it can be seen that when the LNA 28 is operated during walking, the acquisition rate tends to increase.

  The vibration detection unit 70 is a device that detects such vibration, and for example, an acceleration sensor, a gyro sensor, a solar cell, or the like can be used. The acceleration sensor detects acceleration, the gyro sensor detects angle and angular velocity, and the solar cell detects the amount of energy from the sun. The vibration state can be determined according to these detection results.

When receiving a detection signal from the vibration detection unit 70, the control unit 40 transmits this detection signal to the reception unit 30.
The signal amplification control means 62 of the GPS signal processing unit 60 determines the vibration state based on the detection signal received from the control unit 40. Specifically, a vibration determination threshold value for determining the vibration state is set in advance, and it is determined whether or not the detection value (sensor output) by the vibration detection unit 70 is equal to or greater than the vibration determination threshold value. As a determination method, for example, when the detection value always exceeds the vibration determination threshold for a certain time, the detection value (sensor output) is equal to or greater than the vibration determination threshold, or the detection value is a certain time There is a method in which the sensor output is equal to or greater than the vibration determination threshold when the number of times the vibration determination threshold is exceeded is a predetermined number or more. In addition, the threshold value for vibration determination is set according to the detection method of the vibration detection unit 70, and is appropriately adjusted.

  The signal amplification control means 62 controls the operation of the LNA 28 by outputting a control signal to the control signal input terminal 286 of the LNA 28 according to the determination result. Specifically, when the reception mode is the timekeeping mode, if the detected value is equal to or greater than the vibration determination threshold, an ON signal is output to the control signal input terminal 286, and the LNA 28 is controlled to be in an operating state. On the other hand, when the detected value is less than the vibration determination threshold, an off signal is output to the control signal input terminal 286, and the LNA 28 is controlled to be stopped.

[Reception Processing of Second Embodiment]
In the second embodiment, an acceleration sensor is used as the vibration detection unit 70, and the signal amplification control unit 62 controls the operation of the LNA 28 according to the detection value detected by the vibration detection unit 70.
The following is a reception process that is applied in both the timekeeping mode and the positioning mode.
In the reception process of the second embodiment, as shown in FIG. 14, the LNA 28 before the start of reception is controlled to be turned off (S10), the satellite search (S3) after the start of reception is started, and the satellite signal decoding ( The difference from the first embodiment is that the detection value (sensor output) is determined after S5) is started. Each process of S2-S9 is the same as that of the first embodiment.

  First, after the LNA 28 is controlled to be turned off (S10), it is determined whether or not the detection value (sensor output) by the vibration detection unit 70 is equal to or greater than a vibration determination threshold value (S11). When the detected value (sensor output) is equal to or greater than the vibration determination threshold value (S11: Yes), the signal amplification control means 62 outputs an ON signal to the control signal input terminal 286, and controls the LNA 28 to be in an operating state (S12). ). On the other hand, when the detected value (sensor output) is less than the vibration determination threshold value (S11: No), the process proceeds to S2.

Further, after starting the satellite search in S3, it is determined whether or not the detection value (sensor output) by the vibration detection unit 70 is equal to or greater than the vibration determination threshold value (S31). When the detected value (sensor output) is equal to or greater than the vibration determination threshold value (S31: Yes), the signal amplification control means 62 outputs an ON signal to the control signal input terminal 286, and controls the LNA 28 to be in an operating state (S32). ). On the other hand, when the detected value (sensor output) is less than the vibration determination threshold value (S31: No), an off signal is output to the control signal input terminal 286, and the LNA 28 is controlled to be stopped (S33).
Similarly, after starting satellite signal decoding in S5, it is determined whether or not the detection value (sensor output) by the vibration detector 70 is equal to or greater than the vibration determination threshold (S51). When the detected value (sensor output) is equal to or greater than the vibration determination threshold value (S51: Yes), the signal amplification control means 62 outputs an ON signal to the control signal input terminal 286, and controls the LNA 28 to be in an operating state (S52). ). On the other hand, when the detected value (sensor output) is less than the vibration determination threshold value (S51: No), an off signal is output to the control signal input terminal 286, and the LNA 28 is controlled to be stopped (S53).

According to such 2nd Embodiment, in addition to the effect of the said 1st Embodiment, the following effect is acquired.
During the satellite signal reception process, the presence or absence of vibration is determined according to the detection value (sensor output) from the vibration detection unit 70, and the signal amplification control means 62 controls the LNA 28 according to the determination result. Therefore, when vibration occurs in the arm swing or in the vehicle when the wearer wearing the GPS wristwatch 3 walks, that is, when the detection value (sensor output) is equal to or greater than the vibration determination threshold, the LNA 28 is in the operating state. To control. As a result, satellite signals with weak signal strength can be amplified, and the reception time can be shortened. As a result, power consumption can be reduced, and efficient reception becomes possible.

When operating the LNA 28 in the second embodiment, the operation of the LNA 28 may be controlled in accordance with the timing at which information necessary for various calculations (time measurement calculation, positioning calculation, etc.) in each reception mode is transmitted. . For example, the start timing of the signal transmission period in the timekeeping mode is the transmission start timing of time information (Z count), and the end timing is the transmission end timing of time information (Z count). Further, the start timing of the signal transmission period in the positioning mode is the transmission start timing of subframes 1 to 3, and the end timing is the transmission end timing of subframes 1 to 3.
In the second embodiment, when a solar cell is used as the vibration detection unit 70, the fluctuation amount of the detected value of the solar energy amount within a certain time is compared with the vibration determination threshold, and the fluctuation amount is for vibration determination. When it is equal to or greater than the threshold value, the LNA 28 is controlled to be in an operating state. If the fluctuation amount of the detected value is large, it can be determined that the GPS wristwatch 3 is not in a stationary state but has vibration.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. In the second embodiment, the vibration state is detected as the reception environment. However, in the third embodiment, the solar cell 22 detects the amount of light energy (illuminance, etc.) as the reception environment of the GPS wristwatch 3. And the point which complete | finishes reception according to a detection result and reception mode differs from 2nd Embodiment. The description of the same configuration as that of the first embodiment is omitted.

[Circuit Configuration of Third Embodiment]
The GPS wristwatch 3 of the third embodiment uses the amount of energy from the sun (illuminance, etc.) detected by the solar cell 22 as a detection value, and outputs this detection value to the control unit 40. That is, the solar cell 22 is used as a reception environment detection unit. Then, based on the detection value received from the solar cell 22, a place where the sky near the zenith is open and the illuminance is sufficient, for example, a place where it is outdoors or is blocked by a wall or the like and the sky is not sufficiently open, for example, indoors It is determined whether it is.
As shown in FIG. 16, the solar cell 22 in the third embodiment is configured to output the detected value of the detected energy amount to the control unit 40 as a detection signal.
When receiving the detection signal from the solar cell 22, the control unit 40 transmits this detection signal to the receiving unit 30.

The signal amplification control means 62 of the GPS signal processing unit 60 determines whether or not the detection value included in the detection signal from the control unit 40 is less than the environmental determination threshold value, and the control signal of the LNA 28 according to the determination result. A control signal is output to the input terminal 286 to control the LNA 28. Specifically, the signal amplification control means 62 outputs an ON signal to the control signal input terminal 286 and controls the LNA 28 to be in an operating state when the detected value is less than the environmental determination threshold value. On the other hand, when the energy amount is equal to or greater than the environmental determination threshold value, an off signal is output to the control signal input terminal 286, and the LNA 28 is controlled to be stopped.
That is, when the detected value detected by the solar cell 22 is equal to or greater than the environmental determination threshold, it is determined that the sky near the zenith is open and the illuminance is sufficient, for example, the outdoor, and the detected value is for environmental determination. When it is less than the threshold, it is determined that the user is in a place where the sky is not sufficiently opened due to a wall or the like, for example, indoors.

  Here, the GPS wristwatch 3 of the third embodiment is mounted, the sky near the zenith is open, and the outdoor where the illuminance is sufficient and the sky near the zenith is not sufficiently open, and the indoor where the illuminance is low. FIG. 17 shows the satellite signal acquisition rate in the timekeeping mode when the user is in a room with a window in a part of the wall. According to FIG. 17, when the user is outdoors, the acquisition rate is 100% regardless of the operating state of the LNA 28. On the other hand, when the user is indoors, operating the LNA 28 improves the acquisition rate. Outside, there are many cases where the sky is open compared to indoors, and signals from position satellites are easily received. In addition, a reception environment close to the outdoors can be obtained in a place where the sky is sufficiently open at the window or the like even indoors.

  The third embodiment is different from the second embodiment in that the detection signal of the reception environment is the amount of energy by the solar cell 22. In the third embodiment, as the detection value (energy amount) detected by the solar cell 22 is smaller, the GPS wristwatch 3 is placed in a place where the sky is not open and the illuminance is low, such as indoors. Since it is determined that the intensity is also weak, it is necessary to set the LNA 28 in the operating state when the detected value is less than the environmental determination threshold. The environment determination threshold value may be adjusted as appropriate according to the reception status.

[Reception Processing of Third Embodiment]
The third embodiment is a reception process that is applied in both the timekeeping mode and the positioning mode. As described above, the detection value determination method is different from the second embodiment in that reception is terminated according to the determination result and the reception mode.
That is, as shown in FIG. 18, the processing after the LNA 28 is first controlled to be turned off (S10), the satellite search (S3) is started, and the signal decoding (S5) is started is the same as in the second embodiment. Is different.

  After S10, the signal amplification control means 62 determines whether or not the detection value (sensor output) from the solar cell 22 is less than the environmental determination threshold (S111). When the detected value (sensor output) is less than the environment determination threshold value (S111: Yes), it is determined whether the reception mode is the positioning mode (S112). When the reception mode is the positioning mode (S112: Yes), the reception process is terminated (S114).

On the other hand, if the detected value (sensor output) is equal to or greater than the environmental determination threshold value (S111: No), it is determined that the vehicle is outdoors, and the LNA 28 does not need to be operated, so the process proceeds to S2, which is the next step.
When the detected value (sensor output) is less than the environmental determination threshold value (S101: Yes) and the reception mode is the timekeeping mode (S112: No), the signal amplification control means 62 controls the control signal input terminal 286. The ON signal is output to the LNA 28 and the LNA 28 is controlled to operate (S113).

Further, after S3, the signal amplification control means 62 determines whether or not the detected value from the solar cell 22 is less than the environmental determination threshold value, similarly to S111 (S311). If the detected value is less than the environment determination threshold (S311: Yes), it is determined whether or not the reception mode is the positioning mode (S312). If the reception mode is the positioning mode (S312: Yes), the reception process is terminated (S114).
On the other hand, if the detected value is equal to or greater than the environmental determination threshold value (S311: N), an OFF signal is output to the control signal input terminal 286, the LNA 28 is controlled to be stopped (S314), and the process proceeds to S4. In S314, if it is already stopped, the stopped state is maintained.
When the detected value (sensor output) is less than the environmental determination threshold (S311: Yes) and the reception mode is the timekeeping mode (S312: No), the signal amplification control means 62 controls the control signal input terminal 286. An ON signal is output to the LNA 28 and the LNA 28 is controlled to operate (S313).
In S511, S512, S513, and S514 after S5, the same processing as S311, S312, S313, and S314 is performed.

According to such 3rd Embodiment, in addition to the effect of the said 1st Embodiment, the following effect is acquired.
In the third embodiment, the solar cell 22 detects the amount of sunlight energy (illuminance, etc.), and the signal amplification control means 62 controls the LNA 28 according to the detected energy amount (detected value). Therefore, when the wearer wearing the GPS wristwatch 3 is in a place where the sky with low illuminance is not open, such as indoors, if the detected value is less than the environmental determination threshold, the LNA 28 is controlled to be in an operating state. As a result, satellite signals with weak signal strength can be amplified, and the reception time can be shortened. Also, when receiving in a place where the illuminance is sufficient and the sky is open, such as outdoors, the LNA 28 is always used compared to when the LNA 28 is turned on because the reception can be ensured without operating the LNA 28. Time can be shortened. As a result, the current consumption value can be reduced, and efficient reception is possible.
Further, the solar cell 22 is used as a part of the power supply device 90 and is information for determining a reception environment as in the above embodiment while generating a current by photovoltaic power generation and filling the secondary battery 24. The amount of sunlight energy is detected and output to the control unit 40. Therefore, it is not necessary to provide another device as a reception environment detection unit for obtaining information for determining the reception environment, and the device can be downsized.

Furthermore, when the detected value is less than the environment determination threshold value and the positioning mode is set (when the reception environment is not good), since the reception is terminated, the power consumption can be suppressed.
For example, in an environment where a GPS satellite signal cannot be received originally, such as in a building or underground mall, data cannot be acquired even if it is amplified by the signal amplification means. Since the signal strength is particularly weak in the positioning mode, it is necessary to amplify by the signal amplifying means. However, in such an environment, the possibility of reception is significantly reduced. Therefore, if the reception operation is terminated in such a case, it is not necessary to continue useless reception processing and decoding processing, and power consumption can be suppressed.

When the LNA 28 is operated in the third embodiment (when the timekeeping mode and the reception environment are not good), the operation of the LNA 28 may be controlled in accordance with the timing at which information necessary for timekeeping calculation is transmitted. . The start timing of the signal transmission period in the time measurement mode is the transmission start timing of the time information (Z count), and the end timing is the transmission end timing of the time information (Z count).
Moreover, in order to determine a reception environment, although the solar cell 22 was used in 3rd Embodiment, it is not restricted to this. For example, when the amount of ultraviolet rays is detected using an ultraviolet sensor, and the amount of ultraviolet rays is less than the environmental determination threshold, the LNA 28 may be in an activated state.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. The circuit configuration of the GPS wristwatch 3 of the fourth embodiment is the same as that of the first embodiment. However, the operation of the signal amplification control means 62 is different from that of the first embodiment in that the LNA 28 is stopped in both the timekeeping mode and the positioning mode during satellite search.
That is, when the receiving unit 30 is activated by the control unit 40, as shown in FIG. 19, the signal amplification control means 62 outputs an OFF signal to the control signal input terminal 286 and controls the LNA 28 to be stopped (S10). After that, the receiving unit 30 starts receiving the satellite signal transmitted from the GPS satellite (S2).

  Then, after the satellite is captured in the satellite search step (S3) (S4), the LNA 28 is controlled according to the reception mode (S45). Specifically, when the reception mode is the timekeeping mode, the signal amplification control means 62 outputs an off signal to the control signal input terminal 286, and controls the LNA 28 to be stopped. On the other hand, when the reception mode is the positioning mode, the signal amplification control means 62 outputs an ON signal to the control signal input terminal 286, and controls the LNA 28 to be in an operating state. That is, the same operation as S1 of the first embodiment is performed.

According to such 4th Embodiment, in addition to the effect of the said 1st Embodiment, the following effect is acquired.
In the fourth embodiment, in the satellite search step (S3), the signal amplification control means 62 performs control to output an off signal to the LNA 28 to make it stop. In the satellite search step (S3), the peak current is maximized, but no further current is added by setting the LNA 28 to the stop state. Therefore, the peak current can be reduced and the required battery size can be reduced, so that the satellite signal receiving apparatus can be downsized. Furthermore, power consumption can be reduced and battery life can be extended.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described. The configuration of the GPS wristwatch 3 of the fifth embodiment is the same as that of the first embodiment, and a description thereof will be omitted.

[Reception Processing of Fifth Embodiment]
The GPS wristwatch 3 of the fifth embodiment is different from the first embodiment in that the operation of the LNA 28 is controlled in accordance with the timing at which information necessary for positioning calculation is transmitted in the positioning mode. In the timekeeping mode, the LNA 28 is always stopped and the same processing as that in the first embodiment is performed, and thus the description thereof is omitted.

As shown in FIG. 20, even in the processing in the positioning mode, the processing from S1 to S4 is the same as that in the first embodiment.
Then, before the satellite signal decoding step (S5), the signal amplification control means 62 outputs an off signal to the control signal input terminal 286, and controls the LNA 28 to be stopped (S41).

Thereafter, the satellite signal decoding step (S5) is performed. While this step is being executed, the signal amplification control means 62 is a period (timing) during which the information necessary for positioning calculation is transmitted in the positioning mode. (S53), and when the signal transmission period start timing is reached (S53: Yes), the LNA 28 is turned on (S54). On the other hand, if “No” is determined in S53, the signal amplification control unit 62 continues the determination of the start timing of the signal transmission period without turning on the LNA 28 (S53).
The start timing of the signal transmission period in the positioning mode is the transmission start timing of subframes 1 to 3.
For this reason, as shown in FIG. 21, even when the decoding of the satellite signal is started, the LNA 28 is turned off until the data transmission period, and is controlled to be turned on when the transmission period is reached.

Next, the signal amplification control means 62 determines whether or not it is the end timing of the signal transmission period (S55). Then, when the signal transmission period ends (S55: Yes), the signal amplification control unit 62 turns off the LNA 28 (S56). On the other hand, if “No” is determined in S55, the signal amplification control unit 62 continues the determination of the end timing of the signal transmission period while maintaining the LNA 28 in the on state (S55).
The end timing of the signal transmission period in the positioning mode is the transmission end timing of subframes 1 to 3.
Normally, when the signal transmission period ends and necessary information can be acquired, the decoding process is also completed. Therefore, as shown in FIG. 21, the decoding process is also terminated at the timing when the LNA 28 is turned off, and the next calculation such as positioning calculation is performed. Is performed.

Then, the signal decoding means 64 determines whether or not predetermined data (time data in the timekeeping mode, time data and positioning data in the positioning mode) can be acquired within a preset time (within the timeout time) ( S6).
Here, when the predetermined data can be acquired, the control unit 40 ends the reception by the receiving unit 30 (S7) and corrects the time (in the time measurement mode) or the time as in the first embodiment. And time difference correction (in the positioning mode) is performed (S8).
If the signal decoding unit 64 determines “No” in S6, the control unit 40 ends the receiving process (S9).

According to such 5th Embodiment, in addition to the effect of the said 1st Embodiment, the following effect is acquired.
That is, since the LNA 28 is operated only during a period in which a signal necessary for the positioning process is transmitted, power consumption can be reduced in the positioning mode of the first embodiment compared to the case where the LNA 28 is continuously operated.

In addition, this invention is not limited to said each embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention.
For example, in each of the embodiments described above, the LNA 28 is disposed between the GPS antenna 27 and the RF unit 50, but may be disposed inside the RF unit 50 as shown in FIG.
That is, it is advantageous in terms of signal amplification characteristics that the LNA 28 is disposed in the immediate vicinity of the GPS antenna 27. However, the LNA 28 is disposed inside the RF unit 50 in order to reduce the board area or reduce the cost. Also good.

In the second embodiment, when the reception mode is the positioning mode and the detection value (sensor output) from the vibration detection unit 70 is equal to or greater than the vibration determination threshold, reception of the GPS signal is terminated at that time. You may let them.
For example, when there is an environment in which GPS satellite signals cannot be received originally, such as when vibrations are large, data cannot be acquired even if amplified by the signal amplification means. Since the signal strength is particularly weak in the positioning mode, it is necessary to amplify by the signal amplifying means. However, in such an environment, the possibility of reception is significantly reduced. Therefore, if the reception operation is terminated in such a case, it is not necessary to continue useless reception processing and decoding processing, and power consumption can be suppressed.

In the fourth embodiment, the LNA 28 is stopped in the satellite search process. Similarly, in the second embodiment, the third embodiment, and the fifth embodiment, the LNA 28 may be controlled to be stopped in the satellite search process. According to this, since the peak current in the satellite search process can be reduced and the required battery size can be reduced, the satellite signal receiving apparatus can be downsized. Furthermore, power consumption can be reduced and battery life can be extended.
Furthermore, you may control combining 1st, 4th, 5th embodiment and 2nd, 3rd embodiment. That is, in the positioning mode, the LNA 28 is operated regardless of the detection result of the reception environment as in the first, fourth, and fifth embodiments, and in the time measurement mode, the reception environment is as in the second and third embodiments. The LNA 28 may be controlled according to the detection result.

  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.

  The satellite signal receiving apparatus 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 a wristwatch, and may be applied to various watches such as a pocket watch, a mobile phone, a digital camera, and various portable information terminals.

  DESCRIPTION OF SYMBOLS 3 ... GPS wristwatch, 12 ... Hand, 13 ... Movement, 27 ... GPS antenna, 28 ... LNA, 30 ... Receiving unit, 40 ... Control unit, 50 ... RF unit, 60 ... GPS signal processing unit, 61 ... Satellite signal search Means 62: Signal amplification control means 63 ... Reception mode setting means 64 ... Signal decoding means 80 ... Time display device 90 ... Power supply device 281 ... Input terminal 282 ... Output terminal 283 ... Operational amplifier 284 ... Power switch, 285... Output changeover switch, 286... Control signal input terminal.

Claims (11)

Receiving means for receiving satellite signals transmitted from the position information satellite;
Receiving control means for controlling the receiving means to perform receiving processing;
A reception mode setting means capable of setting the reception mode to any one of the time measurement mode and the positioning mode, and
The receiving means has a signal amplifying means for amplifying and outputting an inputted received signal in an operating state where power is supplied and outputting an inputted received signal as it is in a stopped state where no power is supplied. And
The reception control means controls the signal amplification means to be stopped when the reception mode is set to the timekeeping mode, and operates the signal amplification means when the reception mode is set to the positioning mode. A satellite signal receiving device comprising signal amplification control means for controlling the state. The satellite signal receiving device according to claim 1,
Comprising satellite signal search means for searching for the satellite signal by the receiving means;
The signal amplification control means controls the signal amplification means to be stopped during the satellite signal search processing by the satellite signal search means. In the satellite signal receiving device according to claim 1 or 2,
When the reception mode is set to the positioning mode, the signal amplification control means operates the signal amplification means only at a timing at which information necessary for positioning calculation is transmitted in the satellite signal. Receiver device. Receiving means for receiving satellite signals transmitted from the position information satellite;
Receiving control means for controlling the receiving means to perform receiving processing;
Receiving environment detecting means for detecting the receiving environment,
The receiving means has a signal amplifying means for amplifying and outputting an inputted received signal in an operating state where power is supplied and outputting an inputted received signal as it is in a stopped state where no power is supplied. And
The reception control means includes signal amplification control means for controlling the signal amplification means to an operating state when it is determined that the reception environment is not good based on the detection value detected by the reception environment detection means. Satellite signal receiver. The satellite signal receiving device according to claim 4, wherein
It has a reception mode setting means that can set the reception mode to either the time measurement mode or the positioning mode,
Satellite signal characterized in that when the reception mode is a positioning mode and it is determined that the reception environment is not good based on the detection value detected by the reception environment detection means, the reception by the reception means is terminated. Receiver device. In the satellite signal receiving device according to claim 4 or 5,
The signal amplification control means includes
When the reception mode is set to the timekeeping mode, the signal amplification means is operated only at the timing when the time information is transmitted in the satellite signal,
When the reception mode is set to the positioning mode, the signal amplifying means is operated only at a timing at which information necessary for positioning calculation is transmitted in the satellite signal. In the satellite signal receiving device according to any one of claims 4 to 6,
Comprising satellite signal search means for searching for the satellite signal by the receiving means;
The signal amplification control means controls the signal amplification means to be stopped during the satellite signal search processing by the satellite signal search means. In the satellite signal receiving device according to any one of claims 4 to 7,
The satellite signal reception device, wherein the reception environment detection means includes energy detection means for detecting an amount of energy from the sun, and determines the reception environment based on a detection value detected by the energy detection means. In the satellite signal receiving device according to any one of claims 4 to 7,
The reception environment detection unit includes a vibration detection unit that detects a vibration state of the satellite signal reception device, and the reception environment is not good when it is determined that the vibration state is detected based on the detection value detected by the vibration detection unit. A satellite signal receiving device characterized by: A receiving means comprising a signal amplifying means for receiving a satellite signal transmitted from a position information satellite and amplifying the received signal;
A control method for a satellite signal receiving apparatus comprising: a reception control means for controlling the receiving means to perform a reception process;
The reception control means is capable of setting the reception mode to either the time measuring mode or the positioning mode,
When the reception mode is set to the timekeeping mode, the signal amplification means is controlled to be stopped, and when the reception mode is set to the positioning mode, the signal amplification means is controlled to be activated. A control method of a satellite signal receiving device characterized by the above. A receiving means comprising a signal amplifying means for receiving a satellite signal transmitted from a position information satellite and amplifying the received signal;
Receiving control means for controlling the receiving means to perform receiving processing;
A reception environment detecting means for detecting a reception environment, and a control method of a satellite signal receiving device comprising:
The reception control means controls the signal amplification means to a stop state when it is determined that the reception environment is good based on the detection value detected by the reception environment detection means, and when it is determined that the reception environment is bad, A control method for a satellite signal receiving apparatus, wherein the signal amplifying means is controlled to be in an operating state.

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