Satellite signal reception apparatus, control method thereof, and electronic device

Abstract

Provided are a satellite signal receiving apparatus and a control method thereof, and an electronic device, which can suppress peak power while giving consideration to search processing and tracking processing. A baseband control section (350) causes a reception section (20) to operate, and after storing a reception signal in a sample memory section (320), causes the reception section (20) to stop operating, and causes a correlation operation processing section (340) to operate a correlation value for searching for a position information satellite based on the stored reception data. The baseband control section (350) causes the reception section (20) to operate for a portion of a first period that is continuous at a time interval of 20 ms, stores reception data in a storage bank (0), and causes the reception section (20) to stop operating for a remaining period of 1 ms, and causes the correlation operation processing section (340) to operate a correlation value for searching for and tracking a position information satellite based on the reception data stored in the storage bank (0).

Description

Technical Field

[0001] The present invention relates to, for example, a satellite signal receiving device, a control method for a satellite signal receiving device, and an electronic device. Background Technology

[0002] A satellite signal receiving device is known, which receives satellite signals transmitted from location information satellites such as GPS satellites, and obtains time information and current location information based on the received satellite signals.

[0003] Satellite signal receiving devices are mostly integrated into portable or small electronic devices that operate on batteries, thus requiring low peak power consumption. Therefore, a technique for suppressing peak power consumption has been proposed by time-division driving the receiving unit that receives satellite signals and the baseband processing unit that processes the received signals received by the receiving unit (see, for example, Patent Document 1).

[0004] This technology can reduce peak power consumption, but it is difficult to balance the search processing of search satellite signals and the tracking processing of follow satellite signals.

[0005] Furthermore, satellite signals may be lost if the receiving device moves during tracking. In such cases, not only must the tracking process be stopped and the search process restarted, but the decoding of the satellite's position and orbit information must also be performed again, resulting in increased power consumption overall.

[0006] Therefore, a technique has been proposed that includes a mode in which tracking processing is performed while searching for new satellite signals (see, for example, Patent Document 2).

[0007] Patent Document 1: Japanese Patent Application Publication No. 2017-167045

[0008] Patent Document 2: Japanese Patent Application Publication No. 2019-163997

[0009] However, the technology described in Patent Document 2 cannot reduce peak power. Therefore, there is a problem that it is impossible to perform both search processing and tracking processing simultaneously while reducing peak power. Summary of the Invention

[0010] A satellite signal receiving apparatus according to one aspect of the present invention comprises: a receiving unit that receives radio waves of satellite signals transmitted from a location information satellite and outputs a received signal; a storage unit that stores the received signal; a correlation processing unit that calculates a correlation value for searching or tracking the location information satellite based on the received signal stored in the storage unit; and a control unit that controls the receiving unit, the storage unit, and the correlation processing unit, the control unit performing the following processing: activating the receiving unit during a first period, causing the storage unit to store the received signal, stopping the activation of the receiving unit during a second period after the first period, and causing the correlation processing unit to calculate a correlation value for searching or tracking the location information satellite based on the received signal stored in the storage unit. The location information satellite's correlation values ​​are processed sequentially in a third and fourth period at predetermined time intervals: During a portion of the third period, the receiving unit is activated, and the storage unit stores the received signal; during other portions of the third period, the receiving unit is stopped, and the correlation processing unit calculates correlation values ​​for searching and tracking the location information satellite based on the stored received signal; during a portion of the fourth period, the receiving unit is activated, and the storage unit stores the received signal; during other portions of the fourth period, the receiving unit is stopped, and the correlation processing unit calculates correlation values ​​for searching and tracking the location information satellite based on the stored received signal. Attached Figure Description

[0011] Figure 1 This is a block diagram illustrating the circuit structure of a satellite signal receiving device according to an embodiment.

[0012] Figure 2 It is a diagram showing the format of navigation data sent from location information satellites.

[0013] Figure 3 This is a diagram showing the bank of the sampling memory section in the first comparative example.

[0014] Figure 4 This is a diagram showing the timing of the operation on the relevant values ​​of the memory bank used in the first comparison example.

[0015] Figure 5 This is a graph showing the relationship between the positioning action and the peak power in the first comparative example.

[0016] Figure 6 This is a diagram showing the storage body of the sampling memory section in the second comparative example.

[0017] Figure 7 This is a diagram showing the timing of the operation on the relevant values ​​of the memory bank used in the second comparison example.

[0018] Figure 8 This is a graph showing the relationship between the positioning action and the peak power in the second comparative example.

[0019] Figure 9 This is a diagram showing the timing of operations using the relevant values ​​of the memory in this embodiment.

[0020] Figure 10 This is a graph showing the relationship between the positioning action and the peak power in this embodiment.

[0021] Figure 11 This is a graph showing the decrease in receiving sensitivity in this embodiment.

[0022] Figure 12 This is a diagram showing the structure of an electronic device with a satellite signal receiving device.

[0023] Label Explanation

[0024] 1: Electronic clock; 10: Satellite signal receiving device; 12: Antenna; 20: Receiving unit; 30: Baseband unit; 320: Sampling memory unit; 340: Correlation processing unit; 350: Baseband control unit. Detailed Implementation

[0025] Hereinafter, a satellite signal receiving apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0026] Furthermore, the embodiments described below are preferred examples, and therefore various technically preferred limitations are attached. However, unless the spirit of the invention is specifically limited in the following description, the scope of the invention is not limited to these methods.

[0027] Figure 1 This is a block diagram showing the circuit structure of the satellite signal receiving device 10. The satellite signal receiving device 10 shown in this figure is a multi-GNSS receiver capable of positioning based on multiple satellite positioning systems. Furthermore, GNSS is an abbreviation for Global Navigation Satellite System.

[0028] The satellite signal receiving device 10 is composed of one or more semiconductor integrated circuits and includes a receiving section 20 and a baseband section 30.

[0029] The receiver 20 is a circuit that uses antenna 5 to receive radio waves in the frequency band of a location information satellite and outputs the received signal. Within the receiver 20, a processing unit is provided for each GNSS that can be received to receive and process satellite signals. Examples of GNSSs that can be received include GPS, Galileo, GLONASS, and Beidou, and the processing unit corresponding to the GNSS being received operates accordingly.

[0030] In addition, the received GNSS can be selected by the user or set to prioritize the GNSS whose information was successfully received last time.

[0031] In addition, the processing unit includes an amplification circuit for amplifying the received signal from the antenna 5, a bandpass filter for removing signal components outside the frequency band of the satellite signal from the received signal, and a mixer circuit for converting the received signal into an intermediate frequency band signal by mixing the local oscillator signal.

[0032] The baseband unit 30 includes a sampling unit 310, a sampling memory unit 320, a copy code generation unit 330, a correlation processing unit 340, and a baseband control unit 350. For example, the baseband unit 30 is a processor such as a CPU (Central Processing Unit), and each function can be implemented as a module.

[0033] The sampling unit 310 includes an analog-to-digital converter, etc., which samples the received signal output from the receiving unit 20 at a predetermined period and converts it into digital received data.

[0034] The sampling memory unit 320 is an example of a storage unit that stores the received data output from the sampling unit 310. Furthermore, the sampling memory unit 320 can ensure a dedicated area for each type of GNSS, can be shared by multiple types of GNSS, and can be configured to change the size (capacity) of the received data that can be stored. The sampling memory unit 320 can be set to a size that corresponds at least to the received GNSS.

[0035] The copy code generation unit 330 generates a copy code corresponding to the type of GNSS and the location information satellite of the receiving target specified by the baseband control unit 350.

[0036] The correlation processing unit 340 performs calculations on the correlation values ​​between the received data stored in the sampling memory unit 320 and the copy code generated by the copy code generation unit 330.

[0037] The baseband control unit 350 is an example of a control unit, which controls the receiving unit 20, the sampling unit 310, the sampling memory unit 320, the copy code generation unit 330 and the related arithmetic processing unit 340, and generally performs the following processing.

[0038] In detail, firstly, the baseband control unit 350 causes the receiving unit 20 to receive radio waves from the GNSS satellite, causes the sampling unit 310 to sample the received signal output from the receiving unit 20 at a predetermined period, converts it into digital received data, and causes the sampling memory unit 320 to store the received data.

[0039] Second, the baseband control unit 350 causes the copy code generation unit 330 to generate a copy code, and causes the correlation processing unit 340 to calculate the correlation value between the received data stored in the sampling memory unit 320 and the copy code generated by the copy code generation unit 330, and performs the search satellite signal processing, i.e., search processing.

[0040] Third, the baseband control unit 350 causes the copy code generation unit 330 to generate a copy code, and the correlation processing unit 340 calculates the correlation value between the received data stored in the sampling memory unit 320 and the copy code generated by the copy code generation unit 330, and performs tracking processing on the satellite signal that has been tracked.

[0041] Furthermore, in order to obtain position information from GNSS satellites, as described later, it is necessary to receive satellite signals for at least three subframes (18 seconds) per satellite. If the storage size of the received data in the sampling memory unit 320 is not limited, it is also possible to perform tracking processing using the received data stored in the sampling memory unit 320 without interrupting the operation of the receiving unit 20. However, in reality, the capacity of the sampling memory unit 320 is limited, and cost must also be considered. Therefore, the satellite signal receiving device 10 divides the storage size of the sampling memory unit 320 into multiple parts and switches between the received data converted to digital to perform related processing for tracking.

[0042] In addition, the baseband control unit 350 performs the processing of decoding the tracked satellite signals and calculating time information and position information based on the decoded satellite navigation information and the code information contained in the tracked signals.

[0043] For ease of explanation, we will use GPS as an example to illustrate the format of signals transmitted from GNSS satellites. To receive signals from GPS satellites and calculate the current position based on the received signals, it is necessary to decode the orbital information representing the satellite's accurate position. This orbital information is called ephemeris.

[0044] Figure 2 It is a diagram showing the format of navigation data sent from location information satellites, specifically from GPS satellites.

[0045] One cycle of navigation data consists of a 1500-bit frame, which takes 30 seconds to be transmitted from GPS satellites. That is, the data rate of navigation data is 50bps.

[0046] One frame consists of five subframes, from subframe 1 to subframe 5. Each subframe is 300 bits. Subframes 1 to 3 of the five subframes contain the satellite's clock correction information and ephemeris, and the same content is repeatedly transmitted from the GPS satellites.

[0047] Therefore, to obtain all clock correction information and ephemeris data, it takes 18 seconds to receive data from subframe 1 to subframe 3. The navigation data rate of 50 bps means that 1 bit is transmitted from GPS satellites every 20 milliseconds (ms). Therefore, in order to continuously decode the data transmitted from GPS satellites, it is necessary to repeatedly perform the action of receiving part or all of the data within 20 ms every 20 ms.

[0048] In addition, in one frame of navigation data, the data sent by subframe 4 and subframe 5 is divided into 25 pages, and the contents of different pages are sent sequentially in each frame.

[0049] The following will explain, in order, the parallel execution of receiving and storing received signals and the calculation of relevant values ​​for search processing and tracking processing in order to receive satellite signals in real time and continuously using the sampling memory unit 320.

[0050] Furthermore, in the following figures, the operation of receiving the received signal by the receiving unit 20 will be denoted as the RF unit, and the calculation of the correlation value used for search processing and tracking processing in the correlation processing unit 340 will be denoted as the baseband unit, or simply the BB unit.

[0051] Figure 3 This is a diagram illustrating the division of storage capacity in the sampling memory section 320, which serves as the first comparative example. Figure 4 This is a diagram showing the timing of the operation on the relevant values ​​of the memory bank used in the first comparison example.

[0052] like Figure 3 As shown, in the first comparative example, the sampling memory unit 320 is divided into memory bank A and memory bank B. Each memory bank has a capacity to store 20 milliseconds (ms) of received data converted to digital format.

[0053] In this first comparative example, such as Figure 4 As shown, memory bank A and memory bank B are alternately switched every 20ms as a storage sampling memory for storing received data and a correlation processing sampling memory for calculating correlation values, i.e., correlation processing. This alternating switching allows for the simultaneous and real-time reception of signals from the satellite while performing correlation processing.

[0054] Figure 5 This is a graph showing the relationship between the positioning action and the peak power in the first comparative example.

[0055] In the first comparative example, after positioning begins, the correlation processing unit 340 performs correlation processing on the received signals received by the receiving unit 20 to search for satellites. Then, the receiving unit 20 continuously receives and stores signals from the satellites in real time and performs correlation processing on the read-out received data by alternately switching between storage A and storage B.

[0056] The receiving unit 20 consumes approximately a constant amount of power. During the correlation processing in the correlation processing unit 340 of the baseband unit 30, there is a tendency for the power consumed for searching for satellite signals to be higher than the power consumed for tracking. Therefore, in the first comparative example, the sum of the power consumed by the receiving unit 20 and the power consumed by the search processing in the baseband unit 30 is defined as the peak power. Furthermore, the peak power in the first comparative example is set as value A.

[0057] Furthermore, the power consumed to store the received data in one of the memory banks A or B, and the power consumed to read the received data from the other of the memory banks A or B, are negligible compared to the power consumed by the receiving unit 20 and the power consumed by the baseband unit 30.

[0058] In the first comparative example, due to the high peak power, there are not many types of batteries that can be used in the satellite signal receiving device 10. Generally, batteries capable of handling high peak power are expensive and difficult to obtain. Therefore, a second comparative example will be described, which uses a cheaper battery to suppress peak power compared to the first comparative example.

[0059] Figure 6 This is a diagram illustrating the memory bank in the sampling memory section 320 of the second comparative example. Figure 7 This is a diagram showing the timing of the operation on the relevant values ​​of the memory bank used in the second comparison example.

[0060] like Figure 6 As shown, in the second comparative example, the storage area of ​​the sampling memory unit 320 is divided into 20 areas from memory bank 0 to memory bank 19. Each memory bank has a capacity to store 20 milliseconds (ms) of received data converted to digital format.

[0061] like Figure 7 As shown, in the second comparative example, firstly, the receiving unit 20 operates, converting 400ms of received data into digital data and storing it in memory cells 0 to 19 of the sampling memory unit 320. When the 400ms of received data has been stored, the operation of the receiving unit 20 stops, and the correlation processing unit 340 performs correlation processing. This correlation processing is used to search for GPS satellites.

[0062] The time required for correlation processing varies depending on the strength of the received signal. Specifically, in environments with strong received signals, such as outdoors, the time required for correlation processing is shorter, and the search time is also shorter and more varied. On the other hand, in environments with weak signals, such as indoors, the time required for correlation processing is longer, and the search time is also longer.

[0063] In addition, the time required for related processing also depends on the operating speed of the baseband unit 30, in other words, the clock speed. If the processing speed of the related value calculation is fast, more satellites can be searched in a short period of time.

[0064] If the satellite search ends and the received data is decoded to determine the satellite's position, the next real-time reception of signals from the satellite will begin. Therefore, the receiving unit 20 and the tracking processing unit 30 operate in parallel.

[0065] Figure 8 This is a graph showing the relationship between positioning operation and peak power in the second comparative example. In the second comparative example, after the received data is stored from memory 0 to memory 19, the operation of the receiving unit 20 is interrupted, and the baseband unit 30 searches for satellites through correlation processing. Therefore, compared with the first comparative example, the peak power is suppressed to a lower amount corresponding to the interruption of the receiving unit 20's operation. Furthermore, the peak power in the second comparative example is set to value B (<A).

[0066] In the second comparative example, the receiving unit 20 and the correlation processing in the baseband unit 30 for searching for satellite signals do not operate simultaneously. Therefore, it is impossible to search for new satellites while tracking processing is in progress. That is, in situations where the received signal strength changes to weak due to the movement of the satellite signal receiving device 10, or more specifically, when the satellite signal receiving device 10 is inserted into a watch and the arm wearing the watch is lowered and the satellite signal is lost, it is impossible to recapture the satellite.

[0067] In this situation, in order to reacquire the satellite, the baseband control unit 350 needs to temporarily stop the correlation processing unit 340 from tracking, store the received data from the satellite back into the sampling memory unit 320, and then allow the correlation processing unit 340 to perform the search process again. Because the tracking process is stopped, continuous navigation data cannot be decoded, so decoding needs to be performed again, which prolongs the time until the calculated position, making it inconvenient.

[0068] Therefore, this implementation method suppresses peak power to a low level and performs a search even while tracking is in progress.

[0069] First, in this embodiment, the storage area of ​​the sampling memory unit 320 is divided into 20 areas, from memory bank 0 to memory bank 19, similar to the second comparative example. Each memory bank also has the capacity to store received data converted to digital data for 20 milliseconds (ms).

[0070] Figure 9 This is a diagram showing the timing of the positioning action in this embodiment. Figure 10 This is a graph showing the relationship between the positioning action and the peak power in this embodiment.

[0071] In this embodiment, the operation of the receiving unit 20 and the baseband unit 30 at the start of the measurement is the same as in the second comparative example. Specifically, the baseband control unit 350 activates the receiving unit 20, stores 400 ms of digital received data from storage bank 0 (Bank_0) to storage bank 19 (Bank_19) of the sampling memory unit 320, then stops the operation of the receiving unit 20. The stored received data is used to enable the correlation processing unit 340 to perform correlation processing; the operation up to this point is the same as in the second comparative example. Through this correlation processing, GPS satellites are searched.

[0072] Furthermore, during the period when the baseband control unit 350 activates the receiver 20 at the start of positioning is Figure 9 In one example of the first period shown in (1), the period until the operation of the receiving unit 20 is stopped, and the related processing unit 340 performs related processing using the stored received data, is... Figure 9 An example of the second period shown in (2).

[0073] Next, in this embodiment, the post-search tracking process differs from that in the second comparative example.

[0074] To perform tracking, the baseband control unit 350 performs control at 20ms intervals as follows. Furthermore, as mentioned above, 20ms is the period during which 1 bit of data is transmitted from the GPS satellite; to continuously receive navigation data, this 20ms interval is repeatedly executed.

[0075] First, the baseband control unit 350 stores 19ms of the received data out of the 20ms received data in memory 0. After storing the 19ms of received data, the baseband control unit 350 stops the operation of the receiving unit 20. Then, using the 19ms of received data stored in memory 0, the baseband control unit 350 causes the correlation processing unit 340 to perform search processing and tracking processing. Furthermore, the search processing and tracking processing of the correlation processing unit 340 are performed during the 1ms period during which the receiving unit 20 stops operating.

[0076] The first period, in 20ms units, is Figure 9An example of the third period shown in (3).

[0077] Subsequently, the baseband control unit 350 activates the receiving unit 20 again, storing 19ms of the received data from the 20ms received data in the storage unit 1. After storing the 19ms of received data, the baseband control unit 350 stops the operation of the receiving unit 20 and uses the 19ms of received data stored in the storage unit 1 to enable the correlation processing unit 340 to perform search processing and tracking processing.

[0078] The second period, in 20ms increments, is Figure 9 An example of the fourth period shown in (4).

[0079] Hereafter, the baseband control unit 350 performs this action while alternately switching between memory bank 0 and memory bank 1.

[0080] like Figure 9 as well as Figure 10 As shown, in this embodiment, the receiving unit 20 and the correlation processing in the baseband unit 30 do not operate simultaneously, therefore the peak power is suppressed to the same value B as in the second comparative example. Specifically, in this embodiment, the peak power is suppressed to the value B consumed by the correlation processing in the baseband unit 30 used for searching after positioning begins. Furthermore, unlike the second comparative example, in this embodiment, search processing can be performed even while tracking processing is in progress.

[0081] In this embodiment, instead of using 20ms, a shorter 19ms received data is used. This means that the received data used in the correlation processing is reduced, resulting in a decrease in the process gain of replication correlation and a decrease in the sensitivity of GPS signal reception.

[0082] Figure 11 This graph shows the simulation results of how the sensitivity decreases when the sampling time is gradually shortened from 20ms, assuming the sampling time of the received signal is 20ms and the receiving sensitivity is 0dm.

[0083] Furthermore, the process gain P_Gain is represented by the following equation (1).

[0084] P_Gain = 10·log10(Ct)(1)

[0085] In equation (1), Ct is the coherence time, which is the sampling time (ms) of the sampling memory unit 320.

[0086] In this embodiment, the sampling time is 19ms. Compared with the sampling time of 20ms, the receiving sensitivity is reduced by 0.22dBm. However, even if the received signal is weak, peak power can be suppressed, and satellite search can be performed even when tracking processing is in progress.

[0087] Furthermore, in this implementation, the sampling time is 19 ms, but it can also be 1 ms shorter. If the sampling time is shorter, the receiver sensitivity decreases due to the reduction in process gain, but the correlation processing time increases, thus increasing the search capability. Therefore, receiver sensitivity and search capability are in a trade-off relationship.

[0088] Next, the electronic equipment of the satellite signal receiving device 10 with the embodiment will be described.

[0089] Figure 12 This is a block diagram showing the circuit structure of an electronic clock 1, which is an example of an electronic device.

[0090] In addition to the satellite signal receiving device 10 of the embodiment, the electronic clock 1 also includes an antenna 5, a timing device 171, a storage device 172, an input device 173, a drive mechanism 181, a display device 182, and a battery 1000.

[0091] Battery 1000 is the power source for driving the electronic clock 1, which includes the satellite signal receiver 10. The baseband unit 30 in the electronic clock 1 is a processor such as a CPU, which executes various programs stored in the storage device 172 to control the receiver unit 20 in the satellite signal receiver 10 and... Figure 12 In addition to the functions of the related calculation and processing unit 340 omitted in the text, the following functions are also constructed.

[0092] That is, the baseband unit 30 includes a time zone setting unit 52, a time correction unit 53, and a display control unit 54.

[0093] The time zone setting unit 52 sets the time zone data based on the location information obtained from the processing results of the satellite signal receiving device 10. The time correction unit 53 corrects the time data based on the time information obtained from the processing results of the satellite signal receiving device 10 and the time zone data set by the time zone setting unit 52. The display control unit 54 controls the operation of the drive mechanism 181 and controls the display content of the display device 182.

[0094] The timing device 171 includes, for example, a quartz oscillator, and uses a reference signal based on the oscillation signal of the quartz oscillator to update the time data. The input device 173 is, for example, an operating element such as a button or a lever. The operating signal generated by operating the element is provided to the control circuit 50.

[0095] Although electronic clock 1 has been described as an example of an electronic device, electronic devices are not limited to electronic clock 1. Other examples of electronic clocks include wearable terminals, smartphones, tablet terminals, portable navigation devices, car navigation devices, personal computers, etc.

[0096] Based on the above description, the preferred embodiments of this disclosure can be understood, for example, as follows. Furthermore, for ease of understanding, the reference numerals in the accompanying drawings are listed in parentheses below, but this is not intended to limit the invention to the illustrated embodiments.

[0097] A satellite signal receiving device (10) of one mode (mode 1) includes: a receiving unit (20) that receives radio waves of satellite signals transmitted from a location information satellite and outputs a received signal; a storage unit (320) that stores the received signal; a correlation processing unit (340) that calculates correlation values ​​for searching or tracking location information satellites based on the received signal stored in the storage unit (320); and a control unit (350) that controls the receiving unit (20), the storage unit (320), and the correlation processing unit (340). The control unit (350) activates the receiving unit (20) and causes the storage unit (320) to store the received signal during a first period (1). During a second period (2) following the first period (1), the control unit (350) stops the activation of the receiving unit (20) and causes the correlation processing unit (340) to calculate correlation values ​​based on the received signal stored in the storage unit (320). The received signal in 0) is used to calculate the correlation value for searching for location information satellites. In the third period (3) and the fourth period (4) that are consecutively at a specified time interval: In a part of the third period (3), the receiving unit (20) is activated and the storage unit (320) stores the received signal. In the other part of the third period (3), the receiving unit (20) is stopped and the correlation calculation processing unit (340) calculates the correlation value for searching and tracking location information satellites based on the stored received signal. In a part of the fourth period (4), the receiving unit (20) is activated and the storage unit (320) stores the received signal. In the other part of the fourth period (4), the receiving unit (20) is stopped and the correlation calculation processing unit (340) calculates the correlation value for searching and tracking location information satellites based on the stored received signal.

[0098] According to method 1, both search processing and tracking processing can be performed while suppressing peak power.

[0099] In the satellite signal receiving device (10) of the specific mode of mode 1 (mode 2), the storage area of ​​the storage unit (320) is divided into a first storage unit and a second storage unit. The control unit (350) stores the received signal in the first storage unit during a part of the third period (3) and stores the received signal in the second storage unit during a part of the fourth period (4).

[0100] In the satellite signal receiving device (10) of the specific method of method 2 (method 3), the specified time interval is 20 milliseconds.

[0101] Another method (method 4) for controlling the satellite signal receiving device (10) is as follows: the satellite signal receiving device (10) includes: a receiving unit (20) that receives radio waves of satellite signals transmitted from a location information satellite and outputs a received signal; a storage unit (320) that stores the received signal; a correlation processing unit (340) that calculates correlation values ​​for searching or tracking location information satellites based on the received signal stored in the storage unit (320); and a control unit (350) that controls the receiving unit (20), the storage unit (320), and the correlation processing unit (340). The control unit (350) activates the receiving unit (20) during a first period (1) and stores the received signal in the storage unit (320). During a second period (2) following the first period (1), the control unit (350) stops the activation of the receiving unit (20) and stores the correlation value in the storage unit (320). The arithmetic processing unit (340) calculates the correlation values ​​for searching for location information satellites based on the received signals stored in the storage unit (320). During the third period (3) and the fourth period (4) that are sequentially held at predetermined time intervals: during a part of the third period (3), the receiving unit (20) is activated and the storage unit (320) stores the received signals; during the other parts of the third period (3), the receiving unit (20) is stopped and the correlation arithmetic processing unit (340) calculates the correlation values ​​for searching and tracking location information satellites based on the stored received signals; during a part of the fourth period (4), the receiving unit (20) is activated and the storage unit (320) stores the received signals; during the other parts of the fourth period (4), the receiving unit (20) is stopped and the correlation arithmetic processing unit (340) calculates the correlation values ​​for searching and tracking location information satellites based on the stored received signals.

[0102] According to method 4, both search processing and tracking processing can be performed while suppressing peak power.

[0103] The electronic device of method 5 has a satellite signal receiving device (10) of method 1, 2 or 3. According to method 5, both search processing and tracking processing can be performed while suppressing peak power.

[0104] The electronic device of method 6 has a battery that drives the satellite signal receiving device, as in the electronic device of method 5.

Claims

1. A satellite signal receiving device, comprising: The receiving unit receives radio waves from satellite signals transmitted from the location information satellite and outputs the received signal. Storage unit, which stores the received signal; The correlation processing unit calculates correlation values ​​for searching or tracking the location information satellites based on the received signals stored in the storage unit; and The control unit controls the receiving unit, the storage unit, and the related processing unit. The control unit performs the following processing: During the first period, the receiving unit is activated, and the storage unit stores the received signal. During the second period following the first period, the operation of the receiving unit is stopped, and the correlation processing unit calculates correlation values ​​for searching the location information satellite based on the received signal stored in the storage unit. In the third and fourth periods, which are consecutive at specified time intervals: During a portion of the third period, the receiving unit is activated, causing the storage unit to store the received signal. During other parts of the third period, the receiving unit is stopped, and the correlation processing unit calculates correlation values ​​for searching and tracking the location information satellites based on the stored received signals. During a portion of the fourth period, the receiving unit is activated, causing the storage unit to store the received signal. During the remaining portions of the fourth period, the receiving unit is stopped, and the correlation processing unit calculates correlation values ​​for searching and tracking the location information satellites based on the stored received signals. The duration of a portion of the third period is the same as the duration of a portion of the fourth period. The duration of the other portions of the third period is the same as the duration of the other portions of the fourth period. The duration of a portion of the third period and the duration of a portion of the fourth period are both shorter than the duration of the first period. The duration of the other portions of the third period and the duration of the other portions of the fourth period are both shorter than the duration of the second period.

2. The satellite signal receiving device according to claim 1, wherein, The storage area of ​​the storage unit is divided into a first storage unit and a second storage unit. The control unit stores the received signal in the first memory during a portion of the third period and in the second memory during a portion of the fourth period.

3. The satellite signal receiving device according to claim 2, wherein, The specified time interval is 20 milliseconds.

4. A control method for a satellite signal receiving device, wherein, The satellite signal receiving device has: The receiving unit receives radio waves from satellite signals transmitted from the location information satellite and outputs the received signal. Storage unit, which stores the received signal; The correlation processing unit calculates correlation values ​​for searching or tracking the location information satellites based on the received signals stored in the storage unit; and The control unit controls the receiving unit, the storage unit, and the related processing unit. The control unit performs the following processes: During the first period, the receiving unit is activated, and the storage unit stores the received signal. During the second period following the first period, the operation of the receiving unit is stopped, and the correlation processing unit calculates correlation values ​​for searching the location information satellite based on the received signal stored in the storage unit. In the third and fourth periods, which are consecutive at specified time intervals: During a portion of the third period, the receiving unit is activated, causing the storage unit to store the received signal. During other parts of the third period, the receiving unit is stopped, and the correlation processing unit calculates correlation values ​​for searching and tracking the location information satellites based on the stored received signals. During a portion of the fourth period, the receiving unit is activated, causing the storage unit to store the received signal. During the remaining portions of the fourth period, the receiving unit is stopped, and the correlation processing unit calculates correlation values ​​for searching and tracking the location information satellites based on the stored received signals. The duration of a portion of the third period is the same as the duration of a portion of the fourth period. The duration of the other portions of the third period is the same as the duration of the other portions of the fourth period. The duration of a portion of the third period and the duration of a portion of the fourth period are both shorter than the duration of the first period. The duration of the other portions of the third period and the duration of the other portions of the fourth period are both shorter than the duration of the second period.

5. An electronic device having a satellite signal receiving device as described in any one of claims 1 to 3.

6. The electronic device according to claim 5, wherein, The electronic device has a battery that powers the satellite signal receiving device.

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