JP2020028032A - Communication device and power control method - Google Patents

Abstract

To make it possible to reduce power consumption in a place where communication between a communication device and a base station is unstable.SOLUTION: The communication device includes: a detection unit, mounted on a vehicle, for detecting that a drive source of the vehicle has been stopped; a position acquisition unit for acquiring positional information of the vehicle; a wireless communication unit for performing wireless communication with a base station; a storage unit for storing information of a communication area indicating an area where communication with the base station is possible; an additional information acquisition unit for acquiring additional information that is information excluding positional information and affects communication of the wireless communication unit; and a power control unit for determining a time condition for shifting to a stop state in which power consumption of the communication device is minimized on the basis of a relationship between a vehicle position and the communication area, additional information, and the communication status between the wireless communication unit and the base station, when the drive source of the vehicle is stopped.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a communication device and a power control method.

  Various devices are mounted on a vehicle to improve convenience. Some of the devices mounted on the vehicle may operate even after the vehicle is parked. However, since all devices require power for operation, it is required to reduce power consumption in order to effectively use finite power stored in a battery. Patent Document 1 discloses a vehicle-mounted wireless device that periodically transmits data from an electric vehicle to an external reception center, a switch state detection unit that detects a state of a key switch that starts or stops the electric vehicle, Communication means for performing communication between the key switch and the switch state detection means, when the key switch is in an OFF state, calculates the radio wave intensity transmitted and received between the reception center via the communication means, When the calculated radio wave intensity is low, an in-vehicle wireless device including a control unit that controls the operation frequency of the communication unit to be lower than the operation frequency of the communication unit when the key switch is on is disclosed. ing.

JP 2006-115415 A

  In the invention described in Patent Document 1, there is room for improvement in terms of power consumption.

A communication device according to a first aspect of the present invention is a communication device mounted on a vehicle, and acquires a detection unit that detects that a driving source of the vehicle is stopped, and a vehicle position that is a position of the vehicle. A wireless communication unit that wirelessly communicates with the base station; a storage unit that stores information of a communication area indicating an area in which communication with the base station is possible; An additional information obtaining unit that obtains additional information that affects the communication of the unit, and when the driving source of the vehicle is stopped, the relationship between the vehicle position and the communication area, the additional information, and the wireless communication unit and the A power control unit that determines a time condition for shifting to a stop state in which the power consumption of the communication device is minimized based on a communication state of the base station.
A power control method according to a second aspect of the present invention is a power control method executed by a communication device mounted on a vehicle and including a wireless communication unit capable of performing wireless communication with a base station, wherein the driving source of the vehicle is Detecting that the vehicle is stopped, obtaining the vehicle position that is the position of the vehicle, and obtaining additional information that is information excluding position information and that affects communication of the wireless communication unit, When the driving source of the communication device is stopped, the consumption of the communication device is determined based on the relationship between the area where the communication with the base station is possible and the vehicle position, the additional information, and the communication status between the wireless communication unit and the base station. Determining a time condition for a transition to a minimum power outage state.

  According to the present invention, power consumption can be reduced in a place where communication between a communication device and a base station is unstable.

Configuration diagram of communication system S FIG. 3 is a diagram showing an operation state that the communication device 1 can take Flowchart showing processing of power control unit 11 Flowchart showing processing of power control unit 11 Flowchart showing processing of power control unit 11 Diagram showing an example of a radio field intensity map and an operation example

-First Embodiment-
Hereinafter, a first embodiment of a communication device according to the present invention will be described with reference to FIGS.

(Constitution)
FIG. 1 is a configuration diagram of a communication system S including a communication device. The communication system S is mounted on the vehicle 9. In the following, the person riding the vehicle 9 may be referred to as a “user”, and the vehicle 9 may be referred to as a “own vehicle” 9. Further, depending on the situation, the user may be in the vehicle 9. The communication system S includes a communication device 1, a battery 2, a battery control device 3, a temperature sensor 4, a base station 91, a portable terminal 92, and a server 93. In the vehicle, the communication device 1, the battery control device 3, and the temperature sensor 4 are connected by a signal line (not shown).

  The base station 91 and the communication device 1 and the base station 91 and the mobile terminal 92 perform wireless communication described below. The base station 91 and the server 93 are connected via a network, for example, the Internet. Although only one base station 91 is shown in FIG. 1, a plurality of base stations 91 may actually exist. Each of the plurality of base stations 91 can communicate with the server 93.

  The communication device 1 is a communication module for performing wireless communication, a so-called TCU (Telematics Communication Unit). The communication device 1 has a function of notifying a user who has left the vehicle 9 of the position of the vehicle 9 via wireless communication (hereinafter, referred to as a “position notification function”). The communication device 1 may provide a communication function to another device mounted on the vehicle 9.

  The battery 2 is a power supply source for various devices mounted on the vehicle 9. The battery 2 operates not only the communication device 1 but also an air conditioner and a cell motor for starting the engine of the vehicle 9. Therefore, the communication device 1 alone must not use up the power stored in the battery 2. Battery 2 is, for example, a lead storage battery. The battery control device 3 controls charging and discharging of the battery 2 and acquires information of the battery 2 and provides the communication device 1 with the information. The battery control device 3 is, for example, a microcomputer including a sensor such as an ammeter. The information on the battery 2 provided by the battery control device 3 to the communication device 1 includes, for example, the voltage of the battery 2, the dark current, the elapsed time from the start of use, and the like. Temperature sensor 4 measures the temperature of vehicle 9 and transmits it to communication device 1.

  The communication device 1 includes a power control unit 11, a storage unit 12, a position acquisition unit 13, a wireless communication unit 14, a position notification unit 15, and an in-vehicle communication unit 16. The power control unit 11 and the position notification unit 15 perform processing described later. The power control unit 11 and the position notification unit 15 include a CPU as a central processing unit, a ROM as a read-only storage device, and a RAM as a readable and writable storage device, and the CPU stores a program stored in the ROM in the RAM. The functions described later are realized by expanding and executing the functions. However, the power control unit 11 may be realized by a hardware circuit, or may be realized by a reconfigurable logic circuit, for example, an FPGA (Field Programmable Gate Array). Further, the power control unit 11 and the position notification unit 15 may be realized by integrated hardware or may be realized by different hardware.

  The power control unit 11 switches the operation state of the communication device 1 for the purpose of reducing the power consumed by the communication device 1. When the operation state is switched, the communication device 1 may not be able to communicate. Details will be described later. Storage unit 12 is a nonvolatile memory, for example, a flash memory. The storage unit 12 stores a radio field intensity map described later.

  The position acquisition unit 13 acquires information on the current position of the vehicle 9. The position acquisition unit 13 is, for example, a so-called GPS receiver. Radio waves are received from a plurality of satellites constituting the satellite navigation system, and the position of the host vehicle, that is, the latitude and longitude are calculated by analyzing signals contained in the radio waves. However, when the vehicle 9 is equipped with a so-called GPS receiver, the position acquisition unit 13 only needs to have a function of acquiring position information from the GPS receiver.

  The wireless communication unit 14 is a wireless communication module compatible with 3G and 4G, and communicates with the existing base station 91. When receiving the position information request from the mobile terminal 92, the position notification unit 15 outputs the information on the current position of the vehicle 9 acquired by the position acquisition unit 13 via the wireless communication unit 14. The in-vehicle communication unit 16 is a communication interface compatible with IEEE802.3 and CAN (Controller Area Network; registered trademark). The additional information acquisition unit 17 communicates with the battery control device 3 via the in-vehicle communication unit 16 to acquire information on the battery 2. Further, the additional information acquisition unit 17 externally acquires weather information at the current position of the vehicle 9 via the wireless communication unit 14. Further, the additional information obtaining unit 17 obtains time information from a clock mounted on the communication device 1 or the position obtaining unit 13, and obtains time zone information according to a predetermined time interval. For example, 3:00 am to 7:00 am is an early morning time zone, and 0:00 am to 2:00 am is a late night time zone.

  The base station 91 performs wireless communication with the communication device 1 and the mobile terminal 92. The base station 91 communicates with the server 93. The base station 91 is a facility installed on the ground, and can constantly communicate. However, the reachable distance of the radio wave output from the base station 91 is limited due to the limitation of the gain and the output of the antenna. For this reason, the operator of the base station 91 creates and distributes a radio field intensity map indicating an area where radio waves from the base station can be reached in advance. The radio field intensity map may be in the form of a map, a list of combinations of the position of the base station 91 and reachable distance, or may be in another format.

  The mobile terminal 92 is a communication device that the user always has, for example, a mobile phone. The mobile terminal 92 includes an input unit operated by the user, a display unit that presents information to the user, and a communication unit that performs a communication function. The mobile terminal 92 transmits a request for transmitting position information (hereinafter, referred to as a “request message”) to the communication device 1 of the vehicle 9 by a user operation. However, the mobile terminal 92 transmits the request message to the server 93 instead of directly transmitting the request message to the communication device 1. Then, the request message is delivered from the server 93 to the communication device 1, and when the communication device 1 transmits the position information to the portable terminal 92, the position information is displayed on the display unit of the portable terminal 92.

  The server 93 communicates with the communication device 1 and the mobile terminal 92 via the base station 91. The server 93 receives the request message from the portable terminal 92 and transmits the request message to the communication device 1. However, since the communication device 1 may not be able to communicate as described later, transmission to the communication device 1 is attempted only once immediately after receiving the request message from the portable terminal 92. No active transmission is performed. In this case, when the communication device 1 connects to the server 93 and checks the presence or absence of the request message, the request message received from the portable terminal 92 is passed to the communication device 1.

(Relationship between location notification function and power)
The position notification function of the communication device 1 is useful when the user is away from the vehicle 9, and in most cases, the ignition switch is off. That is, the position notification function is useful when the amount of available power is limited. Focusing only on the convenience of the position notification function, it is desirable that the communication device 1 always waits for communication and immediately notifies the position of the vehicle 9 upon a request from the user.

  However, waiting for communication consumes power, so it is virtually impossible to always wait for communication. Therefore, in order to reduce power consumption, the power supply to the wireless communication unit 14 is basically turned off, and power is supplied to the wireless communication unit 14 for a short time in a predetermined time cycle. Then, the communication device 1 inquires of the server 93 about the presence or absence of a request message at a timing when the wireless communication unit 14 is energized, and receives the request message if any.

  The communication performed by the wireless communication unit 14 is premised on bidirectional communication, and communication is not possible unless radio waves emitted from the base station 91 can be received. Therefore, when the ignition switch is off, the power control unit 11 of the communication device 1 reduces the power consumption of the communication device 1 based on the above-described radio wave intensity map and the position of the vehicle 9. The power control unit 11 also reduces the power consumption of the communication device 1 in consideration of the passage of time. Regardless of the position of the vehicle 9, if the vehicle 9 has not been operating for a long time, for example, two weeks or more, and has not received a request message, the operation of the communication device 1 is temporarily stopped to reduce power consumption. It is almost zero.

  The power control unit 11 has a timer (hereinafter, referred to as a “DS timer”) for performing a countdown for shifting to a state where power consumption is substantially zero. The standard value of the DS timer is, for example, 24 hours × 14 = 336 hours. When the ignition switch of the vehicle 9 is turned off, the countdown starts from the initial value of 336 hours. When the vehicle 9 is physically accessed or accessed by wireless communication, the countdown of the DS timer is reset. The physical access to the vehicle 9 is, for example, opening / closing of a door or turning on an ignition switch. The access by wireless communication is, for example, reception of a request message.

  However, in a special case described later, the power control unit 11 sets the initial value of the DS timer to a value smaller than the standard value, and quickly reduces the power consumption of the communication device 1 to almost zero. Details of the operation of the power control unit 11 will be described later.

(Operating state)
FIG. 2 is a diagram illustrating an operation state that the communication device 1 can take. That is, the communication device 1 normally takes one of four operation states of intermittent, fine operation, and stop. When the ignition switch is on, it is always in the normal state. When the ignition switch is off, it is in one of an intermittent state, a fine operation state, and a stop state.

  In the normal state, the communication is always performed, and the calculation by the communication device 1 can exhibit the maximum calculation capability without any particular limitation. In the intermittent state, communication is performed intermittently, for example, once every 128 milliseconds, and the communication device 1 is limited in computing capacity in order to reduce power consumption. In the micro operation state, the communication is performed very intermittently, for example, once every 10 seconds, and the communication device 1 has a very limited calculation capability in order to greatly reduce the power consumption. In the stopped state, no communication is performed and no calculation is performed. However, the DS timer operates even in the stop state, and returns to the fine operation state or the intermittent state after a predetermined time has elapsed.

  Note that the specific values in the above description and the numerical values shown in FIG. 2 are examples shown for easy understanding. The essential conditions for the four states described above are that the power consumption is reduced in the order of normal, intermittent, fine operation, and stop, and that the frequency of communication is also reduced. Therefore, it is not always necessary to exhibit 100% computing power in the normal state, and communication may be intermittent in the normal state.

(Operation of power control unit 11)
3 to 5 described below are flowcharts illustrating processing of the power control unit 11 that is started when the ignition switch is turned on by the user. FIGS. 3 to 5 show mutual relationships by circles A to C described later. Although “END” indicating the end of the processing is described in each of FIGS. 3 to 5, there is no difference between them.

  When the ignition switch is turned on by the user, the processing shown in FIG. 3 is started. In FIG. 3, first, in S301, the power control unit 11 acquires weather information around the own vehicle 9 via the wireless communication unit 14. At this time, the position of the vehicle 9 is calculated by the position calculation unit. In subsequent S302, the power control unit 11 acquires a radio wave intensity map around the own vehicle 9 via the wireless communication unit 14. Then, in S303, the power control unit 11 stores the information acquired in S301 and S302 in the storage unit 12. Then, in S304, the power control unit 11 determines whether or not the ignition switch has been turned off. The power control unit 11 returns to S301 when determining that the ignition switch remains on, and proceeds to S305 when determining that the ignition switch has been turned off. However, when returning from S304 to S301, a predetermined time, for example, a waiting time of one minute may be provided.

  In S305, the power control unit 11 performs matching between the vehicle position calculated by the position calculation unit and the radio wave intensity map acquired in S302, for example, identification of the vehicle position in the radio wave intensity map. In S306, the power control unit 11 determines whether or not the own vehicle position is within a communicable area in the radio wave intensity map. If the power control unit 11 determines that the communication device 1 is within the communicable area, the process proceeds to step S307, where the power control unit 11 transitions the communication device 1 to the intermittent state, and ends the processing illustrated in FIG. If the power control unit 11 makes a negative determination in S306, it proceeds to A in a circle, that is, FIG.

  The process illustrated in FIG. 4 is started from S306 in FIG. 3 via a circle A, or from S317 in FIG. 5 via a circle C. In S308 started via the circled A, the power control unit 11 determines whether or not the own vehicle position is near the communicable area in the radio field intensity map. The vicinity of the communicable area is, for example, within 10 meters from the communicable area. The power control unit 11 proceeds to S309 when making a positive determination in S308, and proceeds to S312 when making a negative determination in S308.

  In S309, the power control unit 11 determines whether or not the wireless communication unit 14 can currently receive radio waves. When the power control unit 11 determines that the radio wave can be received, the process proceeds to S314 in FIG. 5 via a circle B, and when it is determined that the radio wave cannot be received, the process proceeds to S310. In S310, the power control unit 11 checks the weather at the current position and the current time zone using the additional information acquisition unit 17. The weather is obtained from the information acquired in S301, and the time zone is a time classification based on the current time, for example, early morning, noon, evening, and night.

  In subsequent S311, the power control unit 11 determines whether there is a possibility of communication based on the weather and the time zone. For example, cloudy weather is most suitable for communication, and rain is not suitable for communication. In addition, the time zone is suitable for communication because the communication volume is generally small in the middle of the night and early in the morning, and the communication volume is relatively large in other time zones, which is not preferable for communication. For example, if either the weather or the time zone is suitable for communication, the power control unit 11 makes an affirmative determination in S311. The power control unit 11 proceeds to S314 in FIG. 5 via a circle B when determining that there is a communication prospect, and proceeds to S312 when determining that there is no communication prospect.

  S312 is executed when a negative determination is made in S308, when a negative determination is made in S311, and when a negative determination is made in S317 of FIG. In these cases, in order, it is clearly away from the range of the radio wave and there is no possibility of receiving the radio wave, there is no possibility that communication is possible from the weather and the time zone, and the state of the battery 2 is poor and stable. This is the case where power supply cannot be expected. In S312, the power control unit 11 performs a user notification indicating that the remote function cannot be provided to the user using a speaker (not illustrated) provided in the vehicle 9, that is, performs a voice output. In subsequent S313, the power control unit 11 shortens the DS timer, sets an initial value to, for example, 30 minutes, and ends the processing illustrated in FIG.

  The process shown in FIG. 5 is started via a circle B when an affirmative determination is made in S309 of FIG. 4 or when an affirmative determination is made in S311 of FIG. In FIG. 5, first, the power control unit 11 acquires information on the battery 2 from the battery control device 3 via the additional information acquisition unit 17 (S314), and acquires the current temperature from the temperature sensor 4 (S315). At S317, the power control unit 11 determines whether the state of the battery 2 is good. For this determination, the information acquired in S314 and S315 is used comprehensively. For example, the condition of the battery 2 is not good because the elapsed time from the start of use of the battery 2 is long, the voltage of the battery 2 exceeds a specified range, the temperature is extremely high or low, and the dark current is large. It is easier to determine that there is not.

  The power control unit 11 proceeds to S318 when determining that the state of the battery 2 is good, and proceeds to S318 when determining that the state of the battery 2 is not good. In step S318, the power control unit 11 performs a user notification indicating that the remote function may not be provided to the user, that is, performs a voice output. In S312, the user is clearly notified that the remote function cannot be provided, but in S318, the user is notified that the remote function may be provided.

  Next, the power control unit 11 causes the communication device 1 to transition to the fine operation state (S319), and waits for a predetermined time, for example, five minutes while performing intermittent communication (S320). Subsequently, the power control unit 11 determines whether or not the user has gone out of the prefecture at least a predetermined number of times n while waiting (S321), and determines that the number of times the user has gone out of service is less than n times. Returns to S320, and proceeds to S322 if it is determined that the number is n or more. The processing of S322 and S323 is the same as the processing of S310 and S311. If a positive determination is made in S323, the process proceeds to S320. If a negative determination is made in S323, the process proceeds to S324. In S324, the power control unit 11 shortens the DS timer and sets it to, for example, 30 minutes, and ends the processing shown in FIG.

(Operation example)
FIG. 6 is a diagram illustrating an example of a radio wave intensity map and an operation example. In the example shown in FIG. 6, the area inside the solid circle indicates an area where communication with the base station 91 is possible. The dashed circle indicates a distance of 10 meters from the boundary. In other words, the center of the solid circle and the center of the dashed circle coincide. Small circles P1 to P3 shown in FIG. P1 is located outside the dashed circle, P2 is located outside the solid circle and inside the dashed circle, and P3 is located inside the solid circle.
When the vehicle 9 is at the position indicated by the reference numeral P1, a negative determination is made in both S306 in FIG. 3 and S308 in FIG. When the vehicle 9 is at the position indicated by the reference sign P2, a negative determination is made in S306 of FIG. 3, and an affirmative determination is made in S308 of FIG. When the vehicle 9 is at the position indicated by the reference symbol P3, an affirmative determination is made in S306 of FIG.

According to the first embodiment, the following operation and effect can be obtained.
(1) The communication device 1 is mounted on the vehicle 9. The communication device 1 includes an in-vehicle communication unit 16 that detects that the driving source of the vehicle 9 has been stopped, a position acquisition unit 13 that acquires position information of the vehicle 9, and a wireless communication unit 14 that performs wireless communication with the base station 91. And a storage unit 12 for storing a radio field intensity map which is information of a communication area indicating an area where communication with the base station 91 is possible, and additional information which is information excluding position information and which affects communication of the wireless communication unit 14. And an additional information acquisition unit 17 to acquire. When the ignition switch of the vehicle 9 is turned off, the communication device 1 further reduces the power consumption of the communication device to a minimum based on the relationship between the vehicle position and the communication area, additional information, and the communication status between the wireless communication unit and the base station 91. And a power control unit 11 for determining an initial value of the DS timer, that is, a time condition for shifting to the stop state. Therefore, since the initial value of the DS timer for shifting to the stop state is appropriately set, power consumption can be reduced in a place where communication between the communication device 1 and the base station 91 is unstable.

(2) When the power control unit 11 determines that the vehicle position is in an area where communication with the base station is possible based on the information on the communication area, the power control unit 11 sets the time condition to the standard condition, and the power consumption of the communication device is reduced. Transition to the state. As described above, the power consumption in the intermittent state is larger than the power consumption in the stop state.

(3) If the power control unit 11 determines that the vehicle position is in an area where communication with the base station may not be possible based on the information on the communication area (S306: NO, S308: YES), the communication device 1 is set to the slightly operating state. Transition to. Then, the power control unit 11 maintains the fine operation state while the communication status between the wireless communication unit 14 and the base station 91 and the additional information satisfy a predetermined condition (S319 to S323). Further, when the communication status between the wireless communication unit 14 and the base station 91 and the additional information do not satisfy the predetermined conditions (S321: YES and S323NO in FIG. 5), the time condition becomes earlier than the standard condition. The DS timer is set so as to be established (S324).

(4) When the power control unit 11 determines that the vehicle position is in an area that cannot clearly communicate with the base station 91 based on the radio field intensity map (S306: NO, S308: NO), the time condition is earlier than the standard condition. The DS timer is set so as to be established (S313). Therefore, waste of power can be prevented.

(5) When the power control unit 11 determines that the battery 2 mounted on the vehicle 9 and supplying power to the communication device 1 is deteriorated (S317: NO), the power control unit 11 does not shift to the fine operation state (proceed to S319). First, the DS timer is set so that the time condition is satisfied earlier than the standard condition (S313). Therefore, it is possible to prevent the communication device 1 from using up a small amount of power stored in the deteriorated battery 2.

(6) Additional information is time zone and weather. Therefore, it is possible to consider the congestion of the communication route according to the time zone and to consider the wireless reachability according to the weather.

(7) When setting the time condition to a value other than the standard condition, the power control unit 11 notifies the occupant of the vehicle 9 (S312, S318). Therefore, the user can recognize that the operation of the communication device 1 is different from the normal operation.

(Modification 1)
In the above-described embodiment, the flowcharts shown in FIGS. 3 to 5 may be modified as follows. (A) If S309 in FIG. 4 is omitted, and a positive determination is made in S308, the process may always proceed to B in a circle, that is, S314 in FIG. (B) S314 to S317 in FIG. 5 may be omitted, and the process may proceed from B in a circle to S318. (C) The value of the DS timer in S313 may be different from the value of the DS timer in S324. (D) In S311 and S323, the communication possibility is determined based on the combination of the time zone and the weather, but may be determined based on only one of the time zone and the weather.

(Modification 2)
The operation state of the communication device 1 may be five or more, or may be only three. When there are three operating states, the intermittent state and the fine operating state are integrated.

(Modification 3)
The communication device 1 may be incorporated in another device. For example, the communication device 1 may be incorporated in a car navigation device that calculates a travel route and guides a user to a route. Further, the communication device 1 may be integrated with the battery control device 3.

  In each of the above-described embodiments and modifications, the program is stored in the ROM (not shown). However, the program may be stored in the storage unit 12. Further, the communication device 1 may include an input / output interface (not shown), and a program may be read from another device via a medium that can be used by the input / output interface and the communication device 1 when necessary. Here, the medium refers to, for example, a storage medium detachable from an input / output interface, or a communication medium, that is, a network such as a wired, wireless, or optical network, or a carrier wave or a digital signal that propagates through the network. In addition, some or all of the functions realized by the program may be realized by a hardware circuit or an FPGA.

  The above-described embodiments and modifications may be combined with each other. Although various embodiments and modified examples have been described above, the present invention is not limited to these contents. Other embodiments that can be considered within the scope of the technical concept of the present invention are also included in the scope of the present invention.

REFERENCE SIGNS LIST 1 communication device 2 battery 3 battery control device 4 temperature sensor 9 vehicle 11 power control unit 12 storage unit 13 position acquisition unit 14 wireless communication unit 15 position notification unit 16 in-vehicle communication unit 17 Additional information acquisition unit 91 ... base station 92 ... portable terminal 93 ... server

Claims (8)

A communication device mounted on a vehicle,
A detection unit that detects that the drive source of the vehicle has been stopped,
A position acquisition unit that acquires a vehicle position that is the position of the vehicle,
A wireless communication unit that performs wireless communication with the base station;
A storage unit that stores information of a communication area indicating an area where communication with the base station is possible,
An additional information acquisition unit that acquires additional information that is information excluding position information and affects communication of the wireless communication unit,
When the driving source of the vehicle is stopped, the power consumption of the communication device is minimized based on the relationship between the vehicle position and the communication area, the additional information, and the communication status between the wireless communication unit and the base station. A communication device comprising: a power control unit that determines a time condition for transition to a state. The communication device according to claim 1,
When the power control unit determines that the vehicle position is in an area in which communication with the base station is possible based on the information on the communication area, the power control unit sets the time condition to a standard condition, and power consumption of the communication device is reduced. Transition to the intermittent state,
A communication device in which the power consumption in the intermittent state is larger than the power consumption in the stop state. The communication device according to claim 2,
The power control unit, when determining that the vehicle position is in an area that may not be able to communicate with the base station based on the information of the communication area, consumes less power than the intermittent state, and more than the stop state. Transitioning to a fine operation state with high power consumption, maintaining the fine operation state while the communication state between the wireless communication unit and the base station and the additional information satisfy a predetermined condition, the wireless communication unit and the base station A communication device that sets the time condition so that the communication condition with a station and the additional information do not satisfy a predetermined condition, so that the time condition is satisfied earlier than the standard condition. The communication device according to claim 2 or 3,
When the power control unit determines that the vehicle position is in an area where the vehicle cannot be clearly communicated with the base station based on the information of the communication area, the time condition is set such that the time condition is satisfied earlier than the standard condition. Communication device to set. The communication device according to claim 3,
When the power control unit determines that the battery mounted on the vehicle and supplying power to the communication device is deteriorated, the time condition is satisfied earlier than the standard condition without shifting to the fine operation state. A communication device for setting the time condition so that The communication device according to any one of claims 1 to 5,
The communication device, wherein the additional information is time zone and weather. The communication device according to any one of claims 1 to 5,
The communication device that, when setting the time condition other than the standard condition, notifies the occupant of the vehicle. A power control method performed by a communication device mounted on a vehicle and including a wireless communication unit capable of wireless communication with a base station,
Detecting that the drive source of the vehicle has been stopped,
Obtaining a vehicle position that is the position of the vehicle;
Acquiring additional information that is information excluding position information and affects communication of the wireless communication unit,
When the drive source of the vehicle is stopped, the communication device is configured based on a relationship between an area where communication with the base station is possible and the vehicle position, the additional information, and a communication state between the wireless communication unit and the base station. And determining a time condition for shifting to a stop state in which power consumption of the power supply is minimum.

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