JP7325322B2 - Wireless communication device and wireless communication method switching method - Google Patents

Description

The present invention relates to communication network switching in a wireless communication device that performs wireless communication using a communication network provided by a mobile communication carrier.

In recent years, the speed of wireless communication has been increasing. LTE (Long Term Evolution) and WiMAX (Worldwide Interoperability for Microwave Access) Release 2.1 are widely used in mobile communication by mobile communication providers (hereinafter referred to as "mobile carrier communication"). Practical application of the fifth generation mobile communication system (5G) is imminent.

In recent years, IT has progressed in the communication environment of mobiles such as trains, and in addition to conventional train radio, that is, operation commands, digital signage using mobile carrier communication, maintenance services, and driving support services have begun to spread. there is Digital signage is train vision, for example. The maintenance service is a service that transfers information from various sensors installed on the train or vehicle logs from the train to the ground supervisor, and the ground supervisor quickly grasps information such as failures and performs maintenance. The driving support service is, for example, a service that transfers driving conditions such as speed or brake operating conditions from a train to a ground supervisor to provide ECO driving support.

In the future, it is expected that the traffic volume of ground-to-vehicle communication in the mobile environment will increase. Among the communication networks provided by mobile carrier communication, there are communication networks (hereinafter referred to as "first communication networks") that have an upper limit on the amount of accumulated data communication on a period basis, such as monthly, and cumulative data communication on a period basis. There is also a communication network (hereinafter referred to as a "second communication network") that does not have an upper limit on the amount. Some wireless communication devices are capable of switching between a plurality of communication networks provided by mobile carrier communication.

The first communication network and the second communication network often use different frequency bands. The second communication network does not have an upper limit on the cumulative amount of data communication per period, but tends to use a higher frequency band and a narrower communication area than the first communication network. Therefore, wireless communication devices may have to use the first communication network, which has a wide communication area, outside the metropolitan area or underground. Then, when the cumulative amount of data communication through the first communication network exceeds the upper limit, the communication speed limit may be imposed not only on the first communication network but also on the second communication network. Therefore, the wireless communication device needs to prevent the amount of data communication over the first communication network from exceeding the upper limit.

JP 2018-67887 A

Patent Document 1 discloses a mobile communication terminal that switches between LTE and WiFi. However, the mobile communication terminal of Patent Document 1 switches from LTE to WiFi when the amount of communication per LTE communication unit is large and the elapsed time after WiFi communication becomes possible is equal to or greater than a threshold. , It did not take into consideration the upper limit of data communication volume stipulated for a period of time such as a month.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. An object of the present invention is to perform mobile carrier communication by appropriately selecting a second communication network having a narrower communication area than the first communication network.

A wireless communication device of the present invention is a wireless communication device mounted on a mobile body, and is a communication unit that performs wireless communication using either a first communication network or a second communication network provided by a mobile communication carrier. , a measuring unit for measuring the cumulative communication traffic of the first communication network of the communication unit during a predetermined measurement period, and a determination unit for determining whether or not the wireless communication device is in the communication area of the second communication network. and, based on the accumulated communication traffic of the communication unit during the measurement period by the first communication network measured by the measurement unit and the area determination result of the determination unit, either one of the first communication network and the second communication network is selected by the communication unit is a communication network used for wireless communication, and the first communication network selects a communication network used for wireless communication, and the first communication network reduces the communication speed when the cumulative communication volume during the measurement period by the first communication network of the communication unit exceeds the upper limit value is limited, and the second communication network has a narrower communication area than the first communication network, and the communication speed is not limited according to the cumulative communication volume during the measurement period of the second communication network of the communication unit. Yes, and the selection unit selects a threshold value equal to or less than the upper limit value determined based on the upper limit value when the wireless communication device is within the communication area of the second communication network, or when the accumulated communication traffic of the communication unit during the measurement period by the first communication network is determined based on the upper limit value is exceeded, the second communication network is selected as the communication network to be used, the wireless communication device is not within the communication area of the second communication network, and the cumulative communication volume of the communication unit over the first communication network during the measurement period is the threshold is not exceeded, the first communication network is selected as the used communication network .

According to the present invention, a first communication network in which the upper limit of the cumulative communication volume is set for each period, and a second communication network that does not have an upper limit of the cumulative communication volume for each period but has a communication area narrower than that of the first communication network. can be appropriately selected for mobile carrier communication.

1 is a diagram showing the configuration of a mobile router of the base technology; FIG. 1 is a diagram showing a configuration of a wireless communication device according to Embodiment 1; FIG. 4 is a flow chart showing the operation of the wireless communication device according to the first embodiment; 4 is a flow chart showing area determination processing of the wireless communication device according to the first embodiment; FIG. 10 is a diagram showing the configuration of a radio communication apparatus according to Embodiment 2; It is a figure which shows an area map. 13 is a flow chart showing area determination processing of the wireless communication device according to the second embodiment; FIG. 12 is a diagram showing the configuration of a wireless communication device according to Embodiment 3; It is a figure which shows the area map which superimposed the route map. 14 is a flowchart showing area determination processing of the wireless communication device according to Embodiment 3. FIG. 3 is a diagram showing the hardware configuration of a control unit of the wireless communication device; FIG. 3 is a diagram showing the hardware configuration of a control unit of the wireless communication device; FIG.

<A. Prerequisite technology>
FIG. 1 shows the configuration of a mobile router 41, which is the underlying technology of the present invention. The mobile router 41 includes a communication unit 12 , an antenna 14 for transmitting/receiving LTE radio waves, an antenna 15 for transmitting/receiving WiMAX radio waves, and a GUI (Graphical User Interface) 42 . A user of the mobile router 41 performs a communication network switching operation on the GUI 42 . Then, the control signal 16 is output from the GUI 42 to the communication unit 12 , and the communication unit 12 performs wireless communication using either one of the antennas 14 and 15 according to the control signal 16 . That is, the communication unit 12 uses the antenna 14 to perform LTE wireless communication, or uses the antenna 15 to perform WiMAX wireless communication. In this way, the mobile router 41 can perform wireless communication by switching between LTE and WiMAX by manual operation of the user.

Here, LTE and WiMAX are examples of communication networks provided by mobile carrier communications. In particular, LTE is an example of the first communication network, which is a communication network in which an upper limit is set for the cumulative communication volume within a predetermined period such as monthly, and the communication speed is limited when the communication volume exceeds the upper limit. be. In the following description, it is assumed that in LTE, an upper limit is set for the cumulative traffic volume on a monthly basis. Also, WiMAX is an example of a second communication network, which is a communication network with a narrower communication area than the first communication network, although there is no communication speed limit according to the accumulated communication traffic like the first communication network. In this specification, the first communication network is LTE, and the second communication network is WiMAX.

The mobile router 41 is assumed to be subject to communication speed restrictions in both LTE and WiMAX when the monthly cumulative communication volume by LTE exceeds the upper limit value. Therefore, the user needs to know the accumulated communication traffic by LTE and switch the communication network to be used between LTE and WiMAX appropriately by operating the GUI 42 .

However, such a switching operation is troublesome for the user. Furthermore, when the mobile router 41 is used for train communication, it is not realistic for the train crew to switch the communication network used by the mobile router 41 separately from the train operation work. Therefore, the wireless communication device described in each of the following embodiments is configured to automatically switch the communication network to be used without requiring user's operation.

<B. Embodiment 1>
<B-1. Configuration>
FIG. 2 shows the configuration of wireless communication apparatus 101 according to the first embodiment. The wireless communication device 101 has a control unit 13 instead of the GUI 42 compared to the configuration of the mobile router 41 of the base technology. The control unit 13 includes a determination unit 131 , a measurement unit 132 and a selection unit 133 .

A wireless communication device 101 is mounted on a mobile object. An example of a moving object is a train. In each of the following embodiments, a description will be given assuming that the moving body is a train.

The determination unit 131 determines whether or not the wireless communication device 101 is located within the WiMAX communication area.

The measurement unit 132 measures the cumulative amount of communication per period of LTE by the communication unit 12 . The period during which the measurement unit 132 measures the cumulative communication traffic (hereinafter referred to as "measurement period") is a period in which the cumulative communication traffic subject to the LTE communication speed limit is determined. 1 month. In other words, the measurement unit 132 measures the cumulative LTE traffic on a monthly basis.

The selection unit 133 acquires the area determination result from the determination unit 131 and acquires the cumulative traffic volume of LTE from the measurement unit 132 . Then, the selection unit 133 selects a communication network to be used for wireless communication of the communication unit 12 between WiMAX and LTE based on these pieces of information. Then, when the selection unit 133 selects a communication network different from the communication network currently used by the communication unit 12 , the selection unit 133 outputs the communication network control signal 16 to the communication unit 12 . The communication unit 12 performs wireless communication by switching communication networks according to the control signal 16 .

<B-2. Operation>
FIG. 3 is a flow chart showing the operation of the wireless communication device 101. As shown in FIG. The operation of the wireless communication apparatus 101 will be described below along the flow of FIG.

In the initial state, the communication unit 12 performs wireless communication using a communication network that uses WiMAX (hereinafter referred to as "used communication network") (step S101).

Next, the measurement unit 132 measures the current cumulative monthly LTE traffic, and outputs the result to the selection unit 133 . Then, the selection unit 133 determines whether or not the cumulative LTE traffic is equal to or greater than a predetermined threshold (step S102). This threshold value is determined to be equal to or less than the upper limit value based on the upper limit value of the monthly accumulated communication volume of LTE that allows communication without imposing a limit on the communication speed. If this upper limit is, for example, 9 GB, the threshold in step S102 is set at, for example, 8.9 GB.

In step S102, if the cumulative amount of LTE communication is equal to or greater than the threshold, the communication speed limit may be imposed if the communication unit 12 performs wireless communication using LTE any more. Therefore, the communication unit 12 continues to use WiMAX without using LTE for the remaining period of the month (step S109).

In step S102, if the cumulative LTE communication traffic is less than the threshold, the selection unit 133 selects based on the area determination result acquired from the determination unit 131, and the wireless communication device 101 continues for a certain period of time, for example, two minutes or longer, and the WiMAX communication area is selected. It is determined whether or not it is outside (step S103).

If the determination of the selection unit 133 in step S103 is negative, the selection unit 133 repeats step S103 until the wireless communication device 101 continues to be out of the WiMAX communication area for two minutes or longer. On the other hand, if the wireless communication device 101 is out of the WiMAX communication area continuously for two minutes or more, the selection unit 133 selects LTE as the communication network used by the communication unit 12 . Then, the selection unit 133 outputs the control signal 16 for switching the communication network to be used to the communication unit 12, and the communication network to be used is switched from WiMAX to LTE in the communication unit 12 (step S104).

After that, the measurement unit 132 measures the monthly accumulated communication traffic of LTE at the present time and outputs it to the selection unit 133 . Then, the selection unit 133 determines whether or not the cumulative LTE traffic is equal to or greater than a predetermined threshold (step S105). This threshold is the same as the threshold in step S102.

In step S105, if the cumulative amount of LTE communication is equal to or greater than the threshold, the communication speed limit may be imposed if the communication unit 12 performs wireless communication using LTE any more. Therefore, the selection unit 133 selects WiMAX as the communication network used in the communication unit 12 . Then, the selection unit 133 outputs the control signal 16 for switching the communication network to be used to the communication unit 12, and the communication network to be used is switched from LTE to WiMAX in the communication unit 12 (step S108). Then, the communication unit 12 continues to use WiMAX for the remaining period of the month (step S109). In this case, the wireless communication device 101 is outside the WiMAX communication area and communication by WiMAX is not always possible, but the communication unit 12 continues to use WiMAX.

In step S105, if the cumulative LTE communication traffic is less than the threshold, the selection unit 133 acquires the current area determination result from the determination unit 131, and based on it, determines whether the wireless communication device 101 is located within the WiMAX communication area. (step S106). If the wireless communication device 101 is not within the WiMAX communication area in step S106, the process of the selection unit 133 returns to step S105. On the other hand, if the wireless communication device 101 is within the WiMAX communication area in step S106, the selection unit 133 outputs the control signal 16 for switching the communication network to be used to the communication unit 12, and the communication unit 12 selects the LTE communication network. to WiMAX (step S108). Then, the processing of the selection unit 133 returns to step S103.

The determination unit 131 determines whether or not the wireless communication device 101 is within the WiMAX communication area at any time, such as at regular intervals. FIG. 4 is a flow chart showing area determination processing by the determination unit 131 of the wireless communication device 101 . Area determination processing according to the first embodiment will be described below along the flow of FIG.

First, the determination unit 131 acquires the radio wave intensity signal 17 from the communication unit 12 (step S201). The radio wave intensity signal 17 includes information on the reception intensity of the WiMAX radio waves received by the antenna 15 . Based on the radio wave intensity signal 17, the determination unit 131 determines whether or not the strength of the received WiMAX radio wave is equal to or greater than a predetermined threshold (step S202). In step S202, if the strength of the received WiMAX radio wave is greater than or equal to the threshold, the determining unit 131 determines that the wireless communication apparatus 101 is within the WiMAX communication area (step S203). On the other hand, if the strength of the received WiMAX radio wave is less than the threshold in step S202, the determining unit 131 determines that the wireless communication device 101 is outside the WiMAX communication area (step S204).

<B-3. Effect>
The wireless communication device 101 of Embodiment 1 is a wireless communication device mounted on a mobile body, and performs wireless communication using either a first communication network or a second communication network provided by a mobile communication carrier. a measuring unit 132 that measures the cumulative communication traffic of the communication unit 12 during a predetermined measurement period over the first communication network, and whether or not the wireless communication device 101 is in the communication area of the second communication network Based on the determination unit 131 that performs area determination, the cumulative communication volume during the measurement period by the first communication network of the communication unit 12 measured by the measurement unit 132, and the determination result of the determination unit 131, the first communication network and the second communication A selection unit 133 that selects one of the networks as a communication network to be used by the communication unit 12 for wireless communication. The first communication network is a communication network in which the communication speed is restricted when the cumulative communication traffic of the communication unit 12 during the measurement period exceeds the upper limit value, and the second communication network communicates from the first communication network. A communication network that covers a small area and does not limit the communication speed according to the cumulative amount of communication. Therefore, according to the wireless communication device 101, the first communication network and the second communication network can be appropriately used together without a switching operation by the user.

In addition, in the wireless communication device 101, the selection unit 133 selects whether the wireless communication device 101 is within the communication area of the second communication network, or the cumulative communication volume of the communication unit 12 over the first communication network during the measurement period reaches the upper limit value. the second communication network is selected as the communication network to be used, the wireless communication device 101 is not within the communication area of the second communication network, and the first threshold of the communication unit 12 is not within the communication area of the second communication network If the cumulative communication traffic within the measurement period by one communication network does not exceed the first threshold, the first communication network is selected as the communication network to be used. Therefore, according to the wireless communication device 101, the first communication network and the second communication network can be used together without the user's switching operation, as long as the cumulative traffic of the first communication network does not exceed the upper limit.

Also, in the wireless communication device 101, the determination unit 131 performs area determination based on the strength of the signal received by the communication unit 12 via the second communication network. Therefore, according to the wireless communication device 101, it is possible to accurately determine the area.

Also, the first communication network is LTE, and the second communication network is WiMAX. Therefore, according to the wireless communication apparatus 101, the wireless communication apparatus 101 can appropriately use both LTE and WiMAX without switching operation by the user.

<C. Embodiment 2>
In the wireless communication apparatus 101 of Embodiment 1, area determination is performed based on the strength of the received WiMAX radio wave. On the other hand, the radio communication apparatus 102 of Embodiment 2 performs area determination using a GPS signal and an area map.

<C-1. Configuration>
FIG. 5 shows the configuration of wireless communication apparatus 102 according to the second embodiment. Radio communication apparatus 102 includes positioning section 135 and area map storage section 134 in control section 13 in the configuration of radio communication apparatus 101 of the first embodiment.

The positioning unit 135 acquires the GPS signal received by the GPS receiver 18 mounted on the moving body, measures the position of the wireless communication device 102 based on the GPS signal, and outputs the position to the determination unit 131 .

The area map storage unit 134 stores an area map provided by a mobile carrier communication service provider that provides WiMAX. The area map is map information as shown in FIG. 6, and includes at least information on areas where WiMAX communication is possible.

The determination unit 131 defines a communication area 20 in which WiMAX communication can be reliably performed from this area map. Then, the determination unit 131 determines whether or not the wireless communication device 102 is within the communication area 20 based on the communication area 20 and the location information of the wireless communication device 102 .

<C-2. Operation>
The overall operation of radio communication apparatus 102 is the same as the overall operation of radio communication apparatus 101 of Embodiment 2 described in the flowchart of FIG. The wireless communication apparatus 102 differs from the wireless communication apparatus 101 in the area determination processing related to steps S103 and S106 in FIG. Area determination processing of the wireless communication device 102 will be described below with reference to the flowchart of FIG.

First, the positioning unit 135 acquires GPS signals from the GPS receiver 18 and measures the position of the wireless communication device 102 based on the GPS signals (step S301).

Next, the determination unit 131 acquires the area map from the area map storage unit 134 and the location information of the wireless communication device 102 from the positioning unit 135, and determines whether the location of the wireless communication device 102 is within the communication area 20 of the area map. is determined (step S302). If the position of the wireless communication device 102 is within the communication area 20 of the area map, the determination unit 131 determines that the wireless communication device 102 is within the communication area (step S303). If it is outside the communication area 20 on the area map, it is determined that the wireless communication device 102 is outside the communication area (step S304).

Note that FIG. 6 shows a rectangular communication area 20 . However, the communication area 20 is not limited to this, and is actually defined according to an area map provided by a mobile carrier communication service provider.

Moreover, in FIG. 5, the configuration in which the control unit 13 includes the area map storage unit 134 has been described. However, if the first communication network and the second communication network are general Internet networks and the control unit 13 can acquire the area map provided by the mobile carrier communication company via the Internet network, the control unit 13 does not include the area map storage unit 134, and may acquire and use an area map provided by a mobile carrier telecommunication company at any time via the Internet network.

<C-3. Effect>
Radio communication device 102 of Embodiment 2 includes positioning section 135 that measures the position of radio communication device 102 . Then, determination section 131 performs area determination based on an area map that defines the communication area of the second communication network and the position of wireless communication device 102 measured by positioning section 135 . Therefore, according to the wireless communication device 102, it is possible to accurately determine the area.

The positioning unit 135 measures the position of the wireless communication device 102 based on the GPS signal received by the GPS receiver mounted on the mobile object. Therefore, the wireless communication device 102 can accurately determine the area. can.

<D. Embodiment 3>
The wireless communication device 102 of Embodiment 2 performed area determination using GPS signals and an area map. On the other hand, in Embodiment 3, the moving object is a train, and the wireless communication device 103 of Embodiment 3 performs area determination using the kilometerage of the train and an area map.

<D-1. Configuration>
FIG. 8 shows the configuration of wireless communication apparatus 103 according to the third embodiment. Radio communication apparatus 103 has the same configuration as radio communication apparatus 102 of Embodiment 2, but differs in that positioning section 135 acquires the mileage of the train from TIMS (Train Information Management System) 21 . TIMS is an example of a train information management system.

The determination unit 131 identifies a section of the train route in which communication with WiMAX is possible by superimposing the train route 22 on the area map 19 acquired from the area map storage unit 134 . For example, in the example of FIG. 9, the section between station B and station C on the train line 22 is specified as a communication area where communication with WiMAX is possible. Then, the determination unit 131 determines whether or not the wireless communication device 103 is within the communication area according to the train kilometer obtained from the positioning unit 135 .

<D-2. Operation>
The overall operation of radio communication apparatus 103 is the same as the overall operation of radio communication apparatus 101 of Embodiment 2 described in the flowchart of FIG. The wireless communication apparatus 103 differs from the wireless communication apparatus 101 in the area determination processing related to steps S103 and S106 in FIG. The area determination processing of the wireless communication device 103 will be described below with reference to the flowchart of FIG.

First, the positioning unit 135 acquires the mileage of the train from the TIMS 21, and identifies the position of the wireless communication device 103 based on the mileage (step S401).

Next, the determination unit 131 acquires the area map from the area map storage unit 134 and the train kilometerage from the positioning unit 135, respectively, and determines whether or not the wireless communication device 103 is within the communication area of the area map (step S402). ). In the example of FIG. 9, assuming that the section between station B and station C on line 22 is set as the communication area, the determining unit 131 determines that the train is located between station B and station C based on the kilometerage of the train. or not. If the train is between B station and C station, determination unit 131 determines that wireless communication device 103 is within the WiMAX communication area (step S403). For example, the determination unit 131 determines that the wireless communication device 103 is outside the WiMAX communication area (step S404).

<D-3. Effect>
In the wireless communication device 103 of Embodiment 3, the moving object is a train, and the positioning unit 135 determines the distance of the wireless communication device 103 based on the distance of the train acquired from the train information management system (TIMS) installed in the train. Measure position. Therefore, according to the wireless communication device 103, it is possible to determine whether or not the wireless communication device 103 is within the WiMAX communication area from the distance of the train, and select a communication network according to the determination result.

<E. Hardware configuration>
The communication unit 12 and the control unit 13 in the wireless communication devices 101 to 103 described above are realized by the processing circuit 81 shown in FIG. That is, processing circuit 81 includes communication section 12 , determination section 131 , measurement section 132 , selection section 133 , area map storage section 134 and positioning section 135 . Dedicated hardware may be applied to the processing circuit 81, or a processor that executes a program stored in a memory may be applied. The processor is, for example, a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, a DSP (Digital Signal Processor), or the like.

When the processing circuit 81 is dedicated hardware, the processing circuit 81 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination of these. The functions of each unit such as the communication unit 12, the determination unit 131, the measurement unit 132, the selection unit 133, the area map storage unit 134, the positioning unit 135, etc. (hereinafter referred to as the “determination unit 131, etc.”) are realized by a plurality of processing circuits 81. Alternatively, the functions of each unit may be collectively realized by one processing circuit.

When the processing circuit 81 is a processor, the functions of the determination unit 131 and the like are realized by a combination of software and the like (software, firmware, or software and firmware). Software or the like is written as a program and stored in memory. As shown in FIG. 12, a processor 82 applied to a processing circuit 81 reads out and executes a program stored in a memory 83 to realize the function of each section. That is, the wireless communication devices 101 to 103 perform wireless communication using either the first communication network or the second communication network provided by the mobile communication carrier when executed by the processing circuit 81; a step of measuring cumulative communication traffic of the wireless communication device over a first communication network within a predetermined measurement period; a step of determining whether or not the wireless communication device is in a communication area of a second communication network; a step of selecting either one of the first communication network and the second communication network as a communication network to be used for wireless communication based on the accumulated communication traffic of the wireless communication device over the first communication network during the measurement period and the result of the area determination; , has a memory 83 for storing the program that will result in execution. In other words, it can be said that this program causes a computer to execute the procedure or method of the determination unit 131 and the like. Here, the memory 83 includes non-volatile memories such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), and EEPROM (Electrically Erasable Programmable Read Only Memory). Or volatile semiconductor memory, HDD (Hard Disk Drive), magnetic disk, flexible disk, optical disk, compact disk, mini disk, DVD (Digital Versatile Disk) and its drive device, etc., or any storage medium that will be used in the future There may be.

The configuration in which each function such as the determination unit 131 is realized by either hardware or software has been described above. However, the configuration is not limited to this, and a configuration in which a part of the determination unit 131 and the like is realized by dedicated hardware and another part is realized by software or the like may be employed.

As described above, the processing circuit can implement each of the functions described above using hardware, software, etc., or a combination thereof. Although the area map storage unit 134 is composed of the memory 83, they may be composed of a single memory 83, or may be composed of individual memories.

In addition, within the scope of the invention, each embodiment can be freely combined, and each embodiment can be appropriately modified or omitted.

12 communication unit, 13 control unit, 14, 15 antenna, 16 control signal, 17 radio wave intensity signal, 18 GPS receiver, 19 area map, 20 communication area, 22 route, 41 mobile router, 81 processing circuit, 82 processor, 83 memory , 101 to 103 wireless communication device, 131 determination unit, 132 measurement unit, 133 selection unit, 134 area map storage unit, 135 positioning unit.

Claims (7)

A wireless communication device mounted on a mobile object,
a communication unit that performs wireless communication using either a first communication network or a second communication network provided by a mobile communication carrier;
a measurement unit that measures an accumulated communication traffic of the first communication network of the communication unit during a predetermined measurement period;
a determination unit that determines whether or not the wireless communication device is in the communication area of the second communication network;
one of the first communication network and the second communication network based on the accumulated traffic of the communication unit during the measurement period over the first communication network measured by the measurement unit and the area determination result of the determination unit; a selection unit that selects one of the communication networks as a communication network to be used by the communication unit for the wireless communication,
The first communication network is a communication network in which a communication speed is limited when the cumulative communication volume of the measurement period of the first communication network of the communication unit exceeds an upper limit value,
The second communication network has a communication area narrower than that of the first communication network, and is a communication network in which a communication speed is not restricted according to the cumulative communication traffic of the second communication network of the communication unit during the measurement period ,
The selection unit
When the wireless communication device is within the communication area of the second communication network, or the cumulative communication volume of the communication unit over the first communication network during the measurement period is equal to or less than the upper limit determined based on the upper limit. when the threshold is exceeded, selecting the second communication network as the communication network to be used;
the first communication when the wireless communication device is not within the communication area of the second communication network and the cumulative traffic of the communication unit over the first communication network during the measurement period does not exceed the threshold; selecting a network as the communication network of use;
wireless communication device. The determination unit performs the area determination based on the strength of the signal received by the communication unit from the second communication network.
A wireless communication device according to claim 1 . Further comprising a positioning unit that measures the position of the wireless communication device,
The determination unit performs the area determination based on an area map that defines the communication area of the second communication network and the position of the wireless communication device measured by the positioning unit.
A wireless communication device according to claim 1 . The positioning unit measures the position of the wireless communication device based on a GPS signal received by a GPS receiver mounted on the mobile object.
The radio communication device according to claim 3 . the moving body is a train,
The positioning unit measures the position of the wireless communication device based on the mileage of the train obtained from a train information management system mounted on the train.
The radio communication device according to claim 3 . The first communication network is LTE and the second communication network is WiMAX,
The radio communication device according to any one of claims 1 to 5 . A wireless communication system switching method by a wireless communication device mounted on a mobile object,
Perform wireless communication using either the first communication network or the second communication network provided by the mobile communication carrier,
measuring the cumulative amount of traffic within a predetermined measurement period over the first communication network of the wireless communication device;
area determination as to whether the wireless communication device is in the communication area of the second communication network;
Either one of the first communication network and the second communication network is used for the wireless communication based on the accumulated communication traffic of the wireless communication device over the first communication network during the measurement period and the result of the area determination. Select as the communication network used, which is the communication network ,
The first communication network is a communication network whose communication speed is limited when the cumulative communication traffic during the measurement period exceeds an upper limit,
The second communication network is a communication network whose communication area is narrower than that of the first communication network and whose communication speed is not restricted according to the cumulative communication traffic of the measurement period of the second communication network ,
When the wireless communication device is within the communication area of the second communication network, or the cumulative communication traffic of the first communication network during the measurement period exceeds a threshold value equal to or lower than the upper limit determined based on the upper limit when selecting the second communication network as the communication network to be used,
the use of the first communication network when the wireless communication device is not within the communication area of the second communication network and the cumulative communication traffic of the first communication network during the measurement period does not exceed the threshold; choose as a communication network,
Wireless communication system switching method.

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