JP2015233195A - Radio communication device, data transmission method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology for determining, as a connection destination of a radio communication device, a mobile communication terminal that needs to receive necessary data at appropriate timing.SOLUTION: A communication system comprises: a mobile communication terminal mounted on each mobile body; and a radio communication device for transmitting, by using radio communication, data to one mobile communication terminal (connection destination terminal) satisfying a prescribed condition. The radio communication device, when an information signal (beacon) is received (S210) and a connection history including a connection ID agreeing with determination target information that is connection identification information included in the received information signal is not stored in a storage unit (S230: NO), determines a mobile communication terminal corresponding to the determination target information to be a connection destination terminal (S260); and, when transmitting data to the determined connection destination terminal and finishing the data transmission, stores a connection history including connection identification information corresponding to the connection destination terminal, in the storage unit.

Description

  The present invention relates to a wireless communication apparatus, a data transmission method, and a program for performing wireless information communication with a mobile communication terminal mounted on a mobile body.

  2. Description of the Related Art Conventionally, a technology for selecting a connection destination (that is, a wireless communication terminal) of a communication apparatus itself in a communication apparatus that performs information communication with a wireless communication terminal connected via a wireless network is known.

  As a technology for selecting this type of connection destination, the communication device counts the number of connections with the radio base station for each radio base station as a radio communication terminal, and the priority is in order from the radio base station with the largest number of connections. As a high one, it has been proposed to select a connection destination (see Patent Document 1).

JP 2011-250158 A

  By the way, a communication system including a mobile communication terminal mounted on a mobile body such as an automobile and a plurality of communication devices installed on the road is known. In this communication system, each communication device sequentially transmits data such as measurement results input from sensors connected to the communication device to one or more mobile communication terminals connected via a wireless network. .

Each communication device constituting such a communication system has a limited communication range. Furthermore, a mobile object equipped with a mobile communication terminal usually moves with time.
In other words, since the mobile unit existing in the communication range of the communication unit is switched over time, the communication unit constituting the communication system changes the mobile unit communication terminal (that is, the connection destination) to which data is to be transmitted over time. There is a need to.

  However, since mobile communication terminals mounted on mobiles that run at high speed pass through the communication range of the communication device in a short time, communication with all mobile communication terminals is completed if the time required to change the connection destination is long. Before that, there was a problem that the mobile communication terminal passed through the communication range of the communication device.

  It is assumed that the connection destination is determined by the technique described in Patent Document 1. Hereinafter, the assumed technology is referred to as a conventional assumed technology. In this conventional assumed technology, the communication device counts the number of connections with the communication device itself for each mobile communication terminal, and selects the connection destinations in order from the mobile communication terminal with the largest number of connections.

  The connection destination selected in such a conventional assumed technology is a mobile communication terminal having a large number of connections. Therefore, the connection destination selected by the communication device in the conventional assumed technology is a mobile communication terminal that has transmitted data in the past. However, the mobile communication terminal to which the communication device has transmitted data has already finished transmitting data.

  For this reason, it is not necessary to select the connection destination selected by the communication device in the conventional assumed technology as the connection destination. By repeating the selection of unnecessary connection destinations in this way, there is a high possibility that other mobile communication terminals to which data should be transmitted cannot be selected.

In other words, in the conventional assumed technology, there is a problem that the mobile communication terminal that should receive data necessary at an appropriate timing cannot be determined as a connection destination in the wireless communication device.
Therefore, an object of the present invention is to provide a technique for determining a mobile communication terminal that should receive data required at an appropriate timing as a connection destination in a wireless communication apparatus.

  The present invention, which has been made to achieve the above object, wirelessly communicates data to a connection destination terminal which is one mobile communication terminal determined from mobile communication terminals (5) mounted on each mobile object. Relates to a wireless communication device (20) for transmitting by

  The wireless communication apparatus of the present invention includes a receiving means (S210), a connection destination determining means (S220 to S260, S263, S267, S270, S272), a transmitting means (S410 to S460), and a destination storage means (S510). S540).

  Among these, the receiving means receives an information signal that is repeatedly transmitted from each of the mobile communication terminals and includes connection identification information that is associated with each mobile communication terminal and identifies a connection target of the wireless communication device. If the determination target information is not stored in the history storage unit, the connection destination determination unit executes determination control for determining the mobile communication terminal corresponding to the determination target information as the connection destination terminal. However, the determination target information mentioned here is connection identification information included in the information signal received by the receiving means. The history storage unit referred to here stores connection identification information corresponding to the mobile communication terminal that has transmitted data in the past.

  The connection target referred to here may be the mobile communication terminal itself or a personal area network (PAN) configured around the mobile communication terminal. That is, the connection identification information may be identification information that identifies the mobile communication terminal itself, or may be identification information that identifies a personal area network.

  Then, the transmission means transmits data to the connection destination terminal determined by the connection destination determination means. Furthermore, when the transmission unit completes transmission of data to the connection destination terminal, the transmission destination storage unit stores a connection history including connection identification information corresponding to the connection destination terminal in the history storage unit.

  That is, the moving body existing in the communication range of one wireless communication device is switched over time. The wireless communication apparatus has not yet transmitted data to a mobile communication terminal (hereinafter referred to as a target terminal) mounted on a mobile body that has newly entered the communication range of the wireless communication apparatus.

  In this case, it is preferable that the wireless communication device transmits data at an early stage with the target terminal as the connection destination terminal. For this reason, in the wireless communication apparatus of the present invention, a mobile communication terminal that has not transmitted data in the past is used as a connection destination terminal.

  As described above, according to the wireless communication apparatus of the present invention, a mobile communication terminal that requires data can be determined as a connection destination terminal. Moreover, in the wireless communication device of the present invention, each connection identification information included in the beacon from the mobile communication terminal, that is, if the determination target information is not included in the history storage unit, the mobile object corresponding to the determination target information The communication terminal is determined as the connection destination terminal. For this reason, according to the wireless communication apparatus of the present invention, it is possible to reduce the processing steps to determine the connection destination terminal, and to shorten the length of time required to determine the connection destination terminal.

That is, according to the wireless communication apparatus of the present invention, a mobile communication terminal that should receive data necessary at an appropriate timing can be determined as a connection destination.
In addition, the reference numerals in parentheses described in the columns of “Claims” and “Means for Solving the Problems” indicate the correspondence with the specific means described in the embodiments described later as one aspect. However, the technical scope of the present invention is not limited.

  In addition to the above-described wireless communication apparatus, the present invention can be realized in various forms such as a data transmission method in the wireless communication apparatus and a program executed by a computer of the wireless communication apparatus to transmit data.

  In particular, if the present invention is implemented as a program, it can be recorded on a computer-readable recording medium such as a DVD-ROM, CD-ROM, hard disk, etc. It can be used by being acquired and activated by a computer via a line as necessary. And by making a computer perform each procedure, the computer can be functioned as a radio | wireless communication apparatus described in Claim 1.

It is a figure which shows the outline | summary of the communication system provided with the radio | wireless communication apparatus with which this invention was applied. It is a block diagram which shows schematic structure of the mobile communication terminal which comprises a communication system. It is a block diagram which shows schematic structure of the radio | wireless communication apparatus with which this invention was applied. It is a flowchart which shows the process sequence of a data transmission process. It is a figure which shows an example of a connection log | history. It is a flowchart which shows the process sequence of a connection destination determination process. It is a flowchart which shows the process sequence of a transmission process. It is a flowchart which shows the process sequence of a threshold value setting process. It is a flowchart which shows the process sequence of a cutting process. It is a flowchart which shows the process sequence of a log | history management process. It is a timing chart which shows the operation example of a communication system. It is a flowchart which shows the process sequence of the connection destination determination process in 2nd Embodiment. It is a flowchart which shows the process sequence of the connection destination determination process in 3rd Embodiment. It is a flowchart which shows an example of the mobile body information in 3rd Embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
[First Embodiment]
<Communication system>
A communication system 1 shown in FIG. 1 includes mobile communication terminals 5 _{1 to} 5 _N mounted on each of the automobiles AM and a plurality of wireless communication devices 20 _{1 to} 20 _M installed on the road.

  In this communication system 1, each wireless communication device 20 transmits data to one mobile communication terminal 5 that satisfies a specified condition from among the mobile communication terminals 5 that exist within the communication range of each wireless communication device 20. Send. Accordingly, the mobile communication terminal 5 is connected to the mobile communication terminal 5 while switching the wireless communication device 20 connected via the wireless network over time when the automobile AM on which the mobile communication terminal 5 is mounted is moving. Receive data from the wireless communication device 20.

  Data in the present embodiment includes pre-defined information. The regulation information in the present embodiment is information whose contents change with time. That is, the regulation information includes, for example, a result that sequentially changes along the time measured by the sensor.

  Note that a known method may be used as a communication method between the mobile communication terminal 5 and the wireless communication device 20. In the present embodiment, ZigBee (ZigBee (registered trademark)) standardized by IEEE 802.15.4, which is a well-known short-range wireless standard, as a communication method between the mobile communication terminal 5 and the wireless communication device 20. Is used.

  A code “M” illustrated in FIG. 1 is an identifier for identifying the wireless communication device 20 and is a natural number of 1 or more. The code “N” is an identifier for identifying the mobile communication terminal 5 and is a natural number of 1 or more.

As shown in FIG. 2, the mobile communication terminal 5 includes a wireless communication circuit 7 and a control unit 9.
Among these, the wireless communication circuit 7 converts data from the control unit 9 into communication data and transmits the communication data via the antenna 11. Furthermore, the wireless communication circuit 7 receives communication data via the antenna 11 and converts the received communication data into data that can be processed by the control unit 9.

  The control unit 9 is a known control device that is configured around a known microcomputer having a ROM, a RAM, and a CPU. The control unit 9 controls each unit constituting the mobile communication terminal 5 including the wireless communication circuit 7. Furthermore, the control part 9 performs the process based on the regulation information included in the data from the wireless communication device 20, or outputs the regulation information to other in-vehicle devices.

  In addition, the mobile communication terminal 5 repeatedly transmits a beacon at a predetermined time interval. The beacon transmitted by the mobile communication terminal 5 includes at least identification information (hereinafter referred to as “connection ID”) for identifying a personal area network (PAN) configured around the mobile communication terminal 5. In addition, the beacon in this embodiment is an example of the information signal described in the claims, and the connection ID in this embodiment is an example of the connection identification information described in the claims.

  That is, each mobile communication terminal 5 performs information communication with the wireless communication device 20 connected via the wireless network. In the information communication, the mobile communication terminal 5 acquires at least data from the wireless communication device 20.

Furthermore, each mobile communication terminal 5 responds (responds) in accordance with various requests from the wireless communication device 20.
<Wireless communication device>
Next, as shown in FIG. 3, the wireless communication device 20 includes a sensing unit 22, a storage unit 24, a wireless communication circuit 26, a control unit 28, and a time measuring unit 30.

  Among these, the sensing unit 22 is a sensor that repeatedly senses the state of the road where the wireless communication device 20 is installed. Examples of the sensor in the present embodiment include a temperature sensor that measures the temperature of the road surface and a strain gauge that measures the strain of the bridge on which the wireless communication device 20 is installed. Each of the results sensed by the sensing unit 22 is generated as the regulation information.

  The storage unit 24 is a known storage device. As this storage device, for example, a rewritable nonvolatile storage device (for example, a hard disk drive, a flash memory, or the like) can be considered. The time measuring unit 30 has a known structure for measuring time.

  The wireless communication circuit 26 converts data from the control unit 28 into communication data, and transmits the communication data via the antenna 29. Further, the wireless communication circuit 26 receives communication data via the antenna 29 and converts the received communication data into data that can be processed by the control unit 28.

  The control unit 28 is a known control device that is configured around a known microcomputer having a ROM, a RAM, and a CPU. The control unit 28 controls each unit constituting the wireless communication device 20 including the wireless communication circuit 26.

  The ROM of the control unit 28 determines a mobile communication terminal 5 (hereinafter referred to as “connection destination terminal”) to be connected via a wireless network, and performs data transmission processing for transmitting data to the determined connection destination terminal. A program to be executed by the control unit 28 is stored.

  That is, the wireless communication device 20 determines the mobile communication terminal 5 that satisfies the specified condition as the connection destination terminal 5 based on the beacon from each of the mobile communication terminals 5. Furthermore, the wireless communication device 20 transmits data to the determined connection destination terminal 5.

Note that the wireless communication device 20 according to the present embodiment may be provided with a sleep mode that reduces power supply to each component of the wireless communication device 20 so as to suppress power consumption. Then, in the wireless communication device 20 in which such a sleep mode is prepared, the wireless communication device 20 is switched to the normal mode in which power is supplied so that each unit constituting the wireless communication device 20 operates at each timing of starting the data transmission process. It may be configured to be configured. Further, in the wireless communication device 20 in which the sleep mode is prepared, power is constantly supplied to the mechanism that realizes the function of receiving data in the wireless communication circuit 26, and other components constituting the wireless communication device 20. Alternatively, power may be supplied at each timing of starting the data transmission process.
<Data transmission process>
Next, data transmission processing executed by the control unit 28 of the wireless communication device 20 will be described. The data transmission process is started at predetermined time intervals.

  In this data transmission process, as shown in FIG. 4, when activated, the control unit 28 determines a mobile communication terminal 5 that satisfies a specified condition from the mobile communication terminals 5 as a connection destination terminal 5. A predetermination process is executed (S110). If there is no mobile communication terminal 5 that satisfies the specified condition, the control unit 28 returns to the data transmission process without determining the connection destination terminal 5 in the connection destination determination process.

  Subsequently, the control unit 28 determines whether or not the connection destination terminal 5 has been determined in the connection destination determination process of the current cycle (S120). As a result of the determination in S120, if the connection destination terminal 5 is not yet determined in the connection destination determination process of this cycle (S120: NO), the control unit 28 shifts the data transmission process to S160 described later in detail. Let

On the other hand, as a result of the determination in S120, if the connection destination terminal 5 has been determined in the connection destination determination process of the current cycle (S120: YES), the data transmission process is shifted to S130.
In S130, the control unit 28 executes a threshold value setting process for setting a threshold value for the number of times described in detail later (S130). Further, the control unit 28 executes a transmission process of transmitting data by connecting to the connection destination terminal 5 determined in the connection destination determination process of the current cycle via the wireless network (S140).

  And the control part 28 performs the cutting | disconnection process which cut | disconnects the connection via the wireless network with the connecting point terminal 5 (S150). Subsequently, the control unit 28 executes history management processing for managing information (hereinafter referred to as “connection history”) related to the mobile communication terminal 5 that has completed transmission of data (S160). Note that the process proceeds to S160 also when the connection destination terminal 5 has not been determined in the connection destination determination process of the current cycle as a result of the determination in S120.

  The connection history referred to here is information that identifies the mobile communication terminal 5 that has completed data transmission, and is stored in the storage unit 24. As shown in FIG. 5, the connection history in the present embodiment includes a connection ID corresponding to the mobile communication terminal 5 (that is, the connection destination terminal 5) that has transmitted data (indicated simply as “ID” in FIG. 5). The time at which data is transmitted to the connection destination terminal 5 (hereinafter referred to as “connection time”) is associated with each data number. The data number referred to here is an identifier that identifies data that is generated with time and transmitted from the wireless communication device 20. That is, the connection history is generated for each data transmitted by the wireless communication device 20. In the present embodiment, the storage unit 24 in which the connection history is stored functions as a history storage unit described in the claims.

Thereafter, the control unit 28 ends the data transmission process and waits until the next activation timing. Until the next start timing, the sleep mode may be set.
Details of the connection destination determination process, threshold setting process, transmission process, disconnection process, and history management process will be described later.
<Destination determination process>
Next, the connection destination determination process executed in S110 of the data transmission process will be described.

  When this connection destination determination process is activated, as shown in FIG. 6, the control unit 28 first determines whether or not a beacon from the mobile communication terminal 5 has been received (S210). As a result of the determination in S210, if the beacon from the mobile communication terminal 5 has not been received (S210: NO), the control unit 28 shifts the connection destination determination process to S250 described in detail later.

  On the other hand, if the result of determination in S210 is that a beacon from mobile communication terminal 5 has been received (S210: YES), control unit 28 receives the beacon received in S210 of the current cycle (hereinafter “received beacon”). It is determined whether or not the reception level is equal to or higher than a predetermined threshold value (S220). This prescribed threshold value is defined in advance by experiments or the like as a reception level of a beacon that guarantees a minimum level of communication quality between the wireless communication device 20 itself and the mobile communication terminal 5 that has transmitted the reception beacon.

  As a result of the determination in S220, if the reception level of the reception beacon is less than the specified threshold (S220: NO), the control unit 28 shifts the connection destination determination process to S250. On the other hand, as a result of the determination in S220, if the reception level of the received beacon is equal to or higher than the specified threshold (S220: YES), the control unit 28 shifts the connection destination determination process to S230.

  In S230, the control unit 28 includes a connection history that includes a connection ID that matches a connection ID (hereinafter referred to as “determination target information”) included in the received beacon in the connection history stored in the storage unit 24. It is determined whether or not exists. That is, in S230, the determination target information included in the received beacon is checked against the connection ID included in each connection history stored in the storage unit 24 to determine whether there is a matching connection ID.

  As a result of the determination in S230, if the connection history including the connection ID that matches the determination target information is stored in the storage unit 24 (S230: YES), the control unit 28 performs the connection destination determination process to S250. To migrate. On the other hand, as a result of the determination in S230, if the connection history including the connection ID that matches the determination target information is not stored in the storage unit 24 (S230: NO), the control unit 28 advances the connection destination determination process to S240. And migrate. In S <b> 240, the control unit 28 stores, in the storage unit 24, mobile body information in which the reception level of the reception beacon is associated with the connection ID included in the reception beacon. The storage unit 24 in which the moving body information is stored functions as an identification information storage unit described in the claims.

  Subsequently, in the connection destination determination process, the control unit 28 determines whether or not a first period having a predetermined length of time has elapsed since the connection destination determination process was activated (S250). The first period referred to here is defined in advance by an experiment or the like as the minimum time length required for determining the connection destination terminal 5, and may be, for example, several tens of milliseconds or several hundreds of milliseconds. It may be seconds.

  As a result of the determination in S250, if the first period has not elapsed since the connection destination determination process was activated (S250: NO), the control unit 28 returns the connection destination determination process to S210. On the other hand, as a result of the determination in S250, if the first period has elapsed since the connection destination determination process was activated (S250: YES), the control unit 28 shifts the connection destination determination process to S260.

  In S260, the control unit 28 determines the mobile communication terminal 5 that satisfies the specified condition as the connection destination terminal 5 based on the mobile body information stored in the storage unit 24 in the connection destination determination process of the current cycle. The specified condition in the present embodiment is that the reception beacon having the maximum reception level is transmitted among the reception beacons included in the mobile unit information stored in the storage unit 24 in the connection destination determination process of the current cycle. is there. That is, in S260 of the present embodiment, the connection ID included in the received beacon having the maximum reception level among the received beacons included in the mobile body information stored in the storage unit 24 in the connection destination determination process of the current cycle. Is determined as the connection destination terminal 5.

Further, in the connection destination determination process, the control unit 28 deletes all the mobile body information stored in the storage unit 24 in the connection destination determination process of the current cycle (S270).
Further, in the connection destination determination process, the control unit 28 specifies the data number of data to be transmitted to the connection destination terminal 5 in the data transmission process of the current cycle (S280).

Thereafter, the connection destination determination process ends, and the process proceeds to S120 of the data transmission process.
That is, when the connection history including the connection ID that matches the determination target information is stored in the storage unit 24, the wireless communication device 20 transmits data to the mobile communication terminal 5 corresponding to the connection ID. It has already been sent. For this reason, in the connection destination determination process of this cycle, this connection destination determination process is terminated without determining the mobile communication terminal 5 as the connection destination terminal.

  On the other hand, if the connection history including the connection ID that matches the determination target information is not stored in the storage unit 24, the wireless communication device 20 has not transmitted data to the mobile communication terminal 5 corresponding to the connection ID. It is. Since such a mobile communication terminal 5 is likely to newly enter the communication range of the wireless communication device 20, the mobile communication terminal 5 is determined as the connection destination terminal 5.

  Furthermore, in the connection destination determination process of the present embodiment, the mobile communication terminal 5 having the maximum beacon reception level is determined as the connection destination terminal 5 among the connection IDs whose connection history is not stored in the storage unit 24. ing.

Note that S230 and S260 in the connection destination determination process of this embodiment are an example of determination control described in the claims.
<Transmission process>
Next, the transmission process executed in S140 of the data transmission process will be described.

  As shown in FIG. 7, when this transmission process is activated, the control unit 28 first specifies the connection destination terminal 5 determined in the previous connection destination determination process in S280. The data of the data number is transmitted (S410). In S410 of the present embodiment, the wireless communication device 20 first transmits a connection request for requesting connection to the wireless network of the connection destination terminal 5 to the connection destination terminal 5. Then, after the wireless communication device 20 receives a connection permission for permitting connection to the wireless network of the connection destination terminal 5 from the connection destination terminal 5, that is, after being connected to the connection destination terminal 5 via the wireless network. The data is transmitted to the connection destination terminal 5.

  Subsequently, the control unit 28 increments the number of transmissions by one (S420). The number of transmissions referred to here represents the number of transmissions of the data having the data number specified in the previous S280. In the present embodiment, the number of transmissions is counted for each data number and connection ID.

Furthermore, the control unit 28 determines whether or not a reception confirmation has been received from the connection destination terminal 5 (S430). The reception confirmation referred to here is a notification indicating that data has been received.
As a result of the determination in S430, if a reception confirmation is received from the connection destination terminal 5 (S430: YES), the control unit 28 ends the transmission process and shifts the process to S150 of the data transmission process. .

  On the other hand, if the reception confirmation is not received from the connection destination terminal 5 as a result of the determination in S430 (S430: NO), the control unit 28 shifts the process to S440. In S440, it is determined whether the data number of the data transmitted in S410 and the number of transmissions of the connection ID corresponding to the connection destination terminal 5 are less than the number of times threshold set in the threshold setting process.

  As a result of the determination in S440, if the number of transmissions is equal to or greater than the number threshold (S440: YES), the control unit 28 ends the transmission process and shifts the process to S150 of the data transmission process. On the other hand, if the result of determination in S440 is that the number of transmissions is less than the number threshold (S440: NO), the control unit 28 has the reception level of the beacon from the connection destination terminal 5 greater than the predefined reception threshold. It is determined whether or not (S450). The reception threshold mentioned here is defined in advance by experiments or the like as a reception level of a beacon that guarantees the minimum level of communication quality with the wireless communication device 20 itself.

  As a result of the determination in S450, if the reception level of the beacon from the connection destination terminal 5 is equal to or less than the reception threshold (S450: NO), the control unit 28 ends the transmission process and proceeds to S150 of the data transmission process. Shift processing. On the other hand, if the reception level of the beacon from the connection destination terminal 5 is larger than the reception threshold (S450: YES), the control unit 28 transmits the data in S410, and the first predetermined time specified in advance has elapsed. It is determined whether or not (S460).

  If the first predetermined time has not elapsed as a result of the determination in S460 (S460: NO), the control unit 28 waits until the first predetermined time elapses, and when the first predetermined time elapses (S460: YES), the transmission process is returned to S410. In S410, the data of the data number specified in the previous S280 is transmitted again to the connection destination terminal 5 determined in the previous connection destination determination process.

  That is, in the transmission process, the data of the data number specified in the previous S280 is transmitted to the connection destination terminal 5 determined in the previous connection destination determination process. In the transmission process, when the data transmission is successful, the transmission process is terminated.

On the other hand, in the transmission process of the present embodiment, when the data transmission fails, the data of the data number specified in the previous S280 is sent to the connection destination terminal 5 determined in the previous connection destination determination process. Send it again. Then, when data transmission fails continuously for the threshold number of times, there is a high possibility that a communication failure has occurred between the connection destination terminal 5 and the wireless communication device 20. Abort transmission. Further, if the reception level of the beacon from the connection destination terminal 5 is equal to or less than the reception threshold value, it is highly likely that the mobile body equipped with the connection destination terminal 5 has moved out of the communication range of the wireless communication device 20. Now, stop sending data.
<Threshold setting process>
Next, the threshold setting process executed in S130 of the data transmission process will be described.

  When this threshold value setting process is started, as shown in FIG. 8, the control unit 28 first determines the number of times of executing the data transmission process (hereinafter referred to as “cycle number”) as a preset number of times. It is determined whether or not this is the case (S310). As a result of the determination in S310, if the number of cycles is less than the set number (S310: NO), the control unit 28 sets a predetermined fixed value as the number threshold (S320). Thereafter, the control unit 28 ends the threshold value setting process, and shifts the process to S140 of the data transmission process.

  On the other hand, if the number of cycles is equal to or greater than the set number as a result of the determination in S310 (S310: YES), the control unit 28 is counted in S420 of the transmission process, and is managed for each data number and connection ID. All the times are read (S330). Subsequently, the control unit 28 calculates a representative value of the number of transmissions read in S330 (S340). The representative value referred to here may be an arithmetic mean result, a mode value, or a median value.

Furthermore, the control unit 28 sets the representative value of the number of transmissions calculated in S340 as a number threshold (S350).
Thereafter, the control unit 28 shifts the process to S140 of the data transmission process.

That is, in the threshold setting process, a representative value of the number of transmissions managed for each data number and connection ID is calculated, and the representative value of the calculated number of transmissions is set as a number threshold. The number-of-times threshold set in the threshold setting process is used for the determination in S440 of the transmission process.
<Cutting process>
Next, the disconnection process executed in S150 of the data transmission process will be described.

  When this disconnection process is activated, as shown in FIG. 9, the control unit 28 first transmits a disconnection request for requesting disconnection of the connection via the wireless network to the connection destination terminal 5 (S510). ). Subsequently, the control unit 28 determines whether or not a disconnection response is received from the connection destination terminal 5 in response to the disconnection request transmitted in S510 (S520). The disconnection response here is a response to permit disconnection of the connection via the wireless network.

  If the disconnection response is received as a result of the determination in S520 (S520: YES), the control unit 28 shifts the disconnection process to S540, which will be described in detail later. On the other hand, if the disconnection response has not been received as a result of the determination in S520 (S520: NO), the control unit 28 has transmitted a disconnection request in S510, and the second predetermined time specified in advance has elapsed. It is determined whether or not (S530). If it is determined in S530 that the second predetermined time has not elapsed since the disconnection request was transmitted (S530: NO), the control unit 28 returns the disconnection process to S520.

  On the other hand, if the second predetermined time has elapsed since the transmission of the cutting process (S530: YES), the control unit 28 shifts the cutting process to S540. The process also proceeds to S540 when a disconnection response is received (S520: YES).

  In S540, the control unit 28 generates a connection history and stores it in the storage unit 24. The connection history in this embodiment is generated by associating the connection ID corresponding to the connection destination terminal 5 with the connection time that is the time when the data is transmitted to the connection destination terminal 5 in the previous 410.

Thereafter, the control unit 28 shifts the process to S160 of the data transmission process.
<History management processing>
Next, the history management process executed in S160 of the data transmission process will be described.

  When this history management process is activated, as shown in FIG. 10, the control unit 28 first acquires one connection history from the connection history stored in the storage unit 24 (S610). Subsequently, the control unit 28 acquires the current time (hereinafter referred to as “current time”) from the time measuring unit 30 (S620).

  Further, the control unit 28 determines whether or not the connection elapsed time from the connection time included in the connection history acquired in S610 to the current time acquired in S620 is equal to or greater than a predetermined value defined in advance ( S630). As a result of the determination in S630, if the connection elapsed time is less than the specified value (S630: NO), the history management process is shifted to S650 described later in detail.

  On the other hand, if the result of determination in S630 is that the connection elapsed time is equal to or greater than the specified value (S630: YES), the control unit 28 deletes the connection history acquired in S610 from the storage unit 24 (S640). Thereafter, the control unit 28 shifts the history management process to S650.

  In S650, the control unit 28 determines whether or not the processing from S610 to S640 has been executed for all the connection histories stored in the storage unit 24. If the result of determination in S650 is that processing has not been executed for all connection histories (S650: NO), the control unit 28 returns the history management processing to S610. In S610, one connection history is acquired from the connection histories that have not executed the processing from S610 to S650, and the process proceeds to S620.

On the other hand, as a result of the determination in S650, if the processing from S610 to S650 has been executed for all connection histories (S650: YES), this history management processing is terminated. Thereafter, the data transmission process in the current cycle is terminated, and the process waits until the next activation timing.
<Operation example of communication system>
Next, the operation of the communication system 1 will be described.

As shown in FIG. 11, in the communication system 1, each of the mobile communication terminals 5 periodically transmits a beacon (SS10) (S10).
On the other hand, the wireless communication device 20 executes a connection destination determination process (S110). In the connection destination determination process, the mobile communication terminal 5 that has not transmitted data is determined as the connection destination terminal 5 based on the beacon from each mobile communication terminal 5. Furthermore, the wireless communication device 20 executes threshold setting processing (S130) and transmission processing (S140).

  In this transmission process, the wireless communication device 20 transmits a connection request (SS20) to the connection destination terminal 5. The connection destination terminal 5 that has received the connection request returns a connection permission (SS30) to the wireless communication device 20 (S30).

  The wireless communication device 20 that has received the connection permission (SS30) transmits data (SS40) to the connection destination terminal 5. Then, the connection destination terminal 5 that has received the data transmits a reception confirmation (SS50) (S40).

  The wireless communication device 20 that has received the reception confirmation (SS50) executes a disconnection process (S150). In the disconnection process, the wireless communication device 20 transmits a disconnection request (SS60) to the connection destination terminal 5. The connection destination terminal 5 that has received the disconnection request returns a disconnection response (SS70) to the wireless communication device 20 (S50).

  The wireless communication device 20 that has received the disconnection response (SS70) executes the history management process (S160), and then ends the data transmission process. And the radio | wireless communication apparatus 20 waits until the next starting timing, and if it starts by the next starting timing, it will detect the mobile communication terminal 5 which satisfy | fills prescription | regulation conditions as the new connection destination terminal 5. FIG. Further, the wireless communication device 20 transmits data to the newly detected connection destination terminal 5.

The wireless communication device 20 repeatedly executes this series of processing.
[Effect of the first embodiment]
As described above, in the communication system 1, the automobile AM existing in the communication range of one wireless communication device 20 is switched over time. The wireless communication device 20 has not yet transmitted data to the mobile communication terminal 5 mounted on the automobile AM newly entering the communication range of the wireless communication device 20. In this case, the radio communication device 20 preferably transmits data at an early stage with the mobile communication terminal 5 newly entering the communication range as the connection destination terminal.

  For this reason, in the connection destination determination process of the present embodiment, each connection ID included in the beacon from the mobile communication terminal 5, that is, if the determination target information is not included in the storage unit 24, the determination target information The corresponding mobile communication terminal 5 is determined as the connection destination terminal.

  That is, according to the connection destination determination process, since the mobile communication terminal 5 that has not transmitted data in the past is the connection destination terminal, the mobile communication terminal 5 that requires data at that time is the connection destination terminal. Can be determined. Moreover, according to the connection destination determination process, it is possible to reduce the processing steps until the connection destination terminal 5 is determined, and it is possible to shorten the time length required to determine the connection destination terminal 5.

In other words, according to the wireless communication device 20, the mobile communication terminal 5 that should receive data necessary for appropriate timing can be determined as the connection destination.
In addition, in the connection destination determination process, the mobile communication terminal 5 whose connection ID is not stored in the storage unit 24 and the beacon having the highest reception level of the beacon received by the wireless communication device 20 itself during the first period. The mobile communication terminal 5 that has transmitted is determined as the connection destination terminal.

  Thus, if the reception level of a beacon is high, there is a high possibility that the communication quality with the wireless communication device 20 itself is good. Therefore, according to the wireless communication device 20, the mobile communication terminal 5 with good communication quality with the wireless communication device 20 itself can be determined as the connection destination terminal 5.

  Furthermore, in the connection destination determination process, if the beacon reception level is less than the specified threshold value, the communication quality with the mobile communication terminal 5 that transmitted the beacon is low and is excluded from the determination target information.

For this reason, according to the radio | wireless communication apparatus 20, it can prevent that the mobile communication terminal 5 in the condition which cannot ensure communication quality is determined as a connecting point terminal.
Further, in the communication system 1, when transmission of data from the wireless communication device 20 to the connection destination terminal 5 fails for the number of times or more, it is highly likely that a communication failure has occurred with the connection destination terminal 5.

  For this reason, in the transmission process, if the transmission of data to the connection destination terminal 5 fails more than the threshold number of times, the transmission of the data is performed even if the connection destination terminal 5 has not succeeded in receiving the data at the present time. It has been cut off.

  According to such a wireless communication device 20, when the possibility that the connection destination terminal 5 can receive data is low, it is possible to make an early transition to transmission of data to another mobile communication terminal 5. As a result, according to the wireless communication device 20, the mobile communication terminal 5 that should receive data necessary for appropriate timing can be determined as the connection destination.

  Further, in the threshold setting process, a representative value of the number of transmissions is set as a number threshold (an example of the prescribed number in the claims). As a result, according to the wireless communication device 20, it is possible to set an appropriate number of times threshold according to the communication environment.

In the transmission process, when reception confirmation is received from the mobile communication terminal 5 that has transmitted data, it is assumed that transmission of data to the mobile communication terminal 5 has been completed.
As a result, according to the wireless communication device 20, when reception confirmation is received from the connection destination terminal 5, it is possible to make an early transition to data transmission to another mobile communication terminal 5. As a result, according to the wireless communication device 20, the mobile communication terminal 5 that should receive data necessary for appropriate timing can be determined as the connection destination.

  By the way, in the communication system 1, when the mobile body in which the connection destination terminal 5 is mounted moves out of the communication range of the wireless communication device 20, it is unlikely that the connection destination terminal 5 can receive data.

  For this reason, in the transmission process, when the reception level of the beacon from the connection destination terminal 5 becomes less than the specified threshold, the connection destination terminal 5 aborts the transmission of the data even if the connection destination terminal 5 has not successfully received the data at the present time. ing.

  According to such a wireless communication device 20, when there is a low possibility that the connection destination terminal 5 can receive data, it is possible to shift to data transmission to another mobile communication terminal 5. As a result, according to the wireless communication device 20, the mobile communication terminal 5 that should receive data necessary for appropriate timing can be determined as the connection destination.

  In the communication system 1, even if the mobile communication terminal 5 has transmitted data from the wireless communication device 20 once, when the specified time has elapsed since the transmission of the data, the mobile communication terminal 5 There is a high possibility that the terminal 5 needs the data at that time again.

  For this reason, in the history management process, the connection history for which a specified time or more has elapsed from the transmission time is deleted. As a result, according to the wireless communication device 20, even the mobile communication terminal 5 that has transmitted the data once can transmit the necessary data to the mobile communication terminal 5 again.

  Further, the wireless communication device 20 stores a connection history for each data in the storage unit 24. As a result, according to the wireless communication device 20, it is possible to determine for each data whether or not the mobile communication terminal 5 that has received the beacon should be the connection destination terminal 5. Therefore, according to the wireless communication device 20, an appropriate connection destination terminal 5 can be determined for each data.

  In the disconnection process, when transmission of data to the connection destination terminal 5 is completed, a release request for requesting connection release is output to the connection destination terminal 5. When receiving a release permission that permits the release of the connection from the connection destination terminal 5 that has received the release request, the connection history is stored in the storage unit 24.

Therefore, according to the wireless communication device 20, even when the connection between the wireless communication device 20 and the connection destination terminal 5 is once performed by the wireless network, the communication system is maintained until the connection is released. The data transmission destination can be switched early.
[Second Embodiment]
The communication system of the second embodiment is mainly different from the communication system 1 of the first embodiment in the processing contents of the connection destination determination process. For this reason, in the present embodiment, the same components and processes as in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and description will be made focusing on connection destination determination processing different from that in the first embodiment. .
<Destination determination process>
When the connection destination determination process of this embodiment is started, as shown in FIG. 12, the control unit 28 first determines whether or not a beacon from the mobile communication terminal 5 has been received (S210). As a result of the determination in S210, if the beacon from the mobile communication terminal 5 has not been received (S210: NO), the control unit 28 ends the connection destination determination process and proceeds to S120 of the data transmission process. Transition.

  On the other hand, if the result of determination in S210 is that a beacon from mobile communication terminal 5 has been received (S210: YES), control unit 28 has the reception level of the received beacon greater than or equal to a predefined threshold value. It is determined whether or not (S220). As a result of the determination in S220, if the reception level of the reception beacon is less than the specified threshold (S220: NO), the control unit 28 ends the connection destination determination process and shifts the process to S120 of the data transmission process. . On the other hand, as a result of the determination in S220, if the reception level of the received beacon is equal to or higher than the specified threshold (S220: YES), the control unit 28 shifts the connection destination determination process to S230.

  In S230, the control unit 28 determines whether or not a connection history including a connection ID that matches the determination target information exists in the connection history stored in the storage unit 24. That is, in S230, the determination target information included in the received beacon is checked against the connection ID included in each connection history stored in the storage unit 24 to determine whether there is a matching connection ID.

  As a result of the determination in S230, if the connection history including the connection ID that matches the determination target information is stored in the storage unit 24 (S230: YES), the control unit 28 ends the connection destination determination process, and the data The process is shifted to S120 of the transmission process.

  On the other hand, as a result of the determination in S230, if the connection history including the connection ID that matches the determination target information is not stored in the storage unit 24 (S230: NO), the control unit 28 moves the connection destination determination process to S263. And migrate. In S263, the mobile communication terminal 5 that satisfies the specified condition is determined as the connection destination terminal 5. The specified condition in the present embodiment is that the mobile communication terminal 5 is associated with a connection ID included in a beacon received in the current cycle (that is, a received beacon). That is, in S263 of this embodiment, the mobile communication terminal 5 corresponding to the determination target information is determined as the connection destination terminal 5.

Further, in the connection destination determination process, the control unit 28 specifies the data number of data to be transmitted to the connection destination terminal 5 in the data transmission process of the current cycle (S280).
Thereafter, the connection destination determination process ends, and the process proceeds to S120 of the data transmission process.

  That is, when the connection history including the connection ID that matches the determination target information is stored in the storage unit 24, the wireless communication device 20 transmits data to the mobile communication terminal 5 corresponding to the connection ID. It has already been sent. For this reason, in the connection destination determination process of this cycle, this connection destination determination process is terminated without determining the mobile communication terminal 5 as the connection destination terminal.

On the other hand, if the connection history including the connection ID that matches the determination target information is not stored in the storage unit 24, the wireless communication device 20 has not transmitted data to the mobile communication terminal 5 corresponding to the connection ID. It is. Since such a mobile communication terminal 5 is likely to newly enter the communication range of the wireless communication device 20, the mobile communication terminal 5 is determined as the connection destination terminal 5.
[Effects of Second Embodiment]
As described above, according to the connection destination determination process of the present embodiment, as in the connection destination determination process of the first embodiment, the mobile communication terminal 5 that should receive data necessary at an appropriate timing is connected to the connection destination terminal. Can be determined as
[Third Embodiment]
The communication system of the third embodiment is mainly different from the communication system 1 of the first embodiment and the second embodiment in the processing contents of the connection destination determination process. For this reason, in the present embodiment, the same configurations and processes as those in the first embodiment and the second embodiment are denoted by the same reference numerals, and the description thereof is omitted. What is the first embodiment and the second embodiment? The different connection destination determination processing will be mainly described.
<Destination determination process>
When the connection destination determination process of the present embodiment is started, as shown in FIG. 13, the control unit 28 first determines whether or not a beacon from the mobile communication terminal 5 has been received (S210). As a result of the determination in S210, if the beacon from the mobile communication terminal 5 has not been received (S210: NO), the control unit 28 shifts the connection destination determination process to S250 described in detail later.

  On the other hand, if the result of determination in S210 is that a beacon from mobile communication terminal 5 has been received (S210: YES), control unit 28 determines whether or not the reception level of the received beacon is greater than or equal to a specified threshold. (S220).

  As a result of the determination in S220, if the reception level of the reception beacon is less than the specified threshold (S220: NO), the control unit 28 shifts the connection destination determination process to S250. On the other hand, as a result of the determination in S220, if the reception level of the received beacon is equal to or higher than the specified threshold (S220: YES), the control unit 28 shifts the connection destination determination process to S230.

  In S230, the control unit 28 determines whether or not a connection history including a connection ID that matches the determination target information exists in the connection history stored in the storage unit 24. That is, in S230, the determination target information included in the received beacon is checked against the connection ID included in each connection history stored in the storage unit 24 to determine whether there is a matching connection ID.

  As a result of the determination in S230, if the connection history including the connection ID that matches the determination target information is stored in the storage unit 24 (S230: YES), the control unit 28 performs the connection destination determination process to S250. To migrate. On the other hand, as a result of the determination in S230, if the connection history including the connection ID that matches the determination target information is not stored in the storage unit 24 (S230: NO), the control unit 28 advances the connection destination determination process to S243. And migrate. In S243, the control unit 28 stores, in the storage unit 24, mobile body information in which the reception level of the reception beacon is associated with the connection ID included in the reception beacon. Furthermore, in S243 of this embodiment, as shown in FIG. 14, the number of times a beacon has been received (that is, the number of times of reception) is associated with mobile object information and stored in the storage unit 24.

  Subsequently, in the connection destination determination process, the control unit 28 determines whether or not a first period having a predetermined length of time has elapsed since the connection destination determination process was activated (S250). The first period referred to here is defined in advance by an experiment or the like as the minimum time length required for determining the connection destination terminal 5, and may be, for example, several tens of milliseconds or several hundreds of milliseconds. It may be seconds. The first period in the present embodiment is an example of the second period described in the claims, and may be a period different from the first period in the first embodiment.

  As a result of the determination in S250, if the first period has not elapsed since the connection destination determination process was activated (S250: NO), the control unit 28 returns the connection destination determination process to S210. On the other hand, as a result of the determination in S250, if the first period has elapsed since the connection destination determination process was activated (S250: YES), the control unit 28 shifts the connection destination determination process to S267.

  In S267, the control unit 28 determines the mobile communication terminal 5 that satisfies the specified condition as the connection destination terminal 5 based on the mobile body information stored in the storage unit in the connection destination determination process of the current cycle. The specified condition in the present embodiment is that the reception beacon having the largest number of receptions is transmitted among the reception beacons included in the mobile unit information stored in the storage unit 24 in the connection destination determination process of the current cycle. is there. That is, in S267 of the present embodiment, the connection ID included in the received beacon with the highest number of receptions among the received beacons included in the mobile body information stored in the storage unit 24 in the connection destination determination process of the current cycle. Is determined as the connection destination terminal 5.

  Furthermore, in the connection destination determination process, the control unit 28 moves the mobile body information of the mobile communication terminal 5 determined as the connection destination terminal 5 among the mobile body information stored in the storage unit in the connection destination determination process of the current cycle. Is deleted (S272).

Further, in the connection destination determination process, the control unit 28 specifies the data number of data to be transmitted to the connection destination terminal 5 in the data transmission process of the current cycle (S280).
Thereafter, the connection destination determination process ends, and the process proceeds to S120 of the data transmission process.

  That is, when the connection history including the connection ID that matches the determination target information is stored in the storage unit 24, the wireless communication device 20 transmits data to the mobile communication terminal 5 corresponding to the connection ID. It has already been sent. For this reason, in the connection destination determination process of this cycle, this connection destination determination process is terminated without determining the mobile communication terminal 5 as the connection destination terminal.

  On the other hand, if the connection history including the connection ID that matches the determination target information is not stored in the storage unit 24, the wireless communication device 20 has not transmitted data to the mobile communication terminal 5 corresponding to the connection ID. It is. Since such a mobile communication terminal 5 is likely to newly enter the communication range of the wireless communication device 20, the mobile communication terminal 5 is determined as the connection destination terminal 5.

Moreover, in the connection destination determination process of the present embodiment, the mobile communication terminal 5 with the largest number of beacons received is determined as the connection destination terminal 5 among the connection IDs whose connection history is not stored in the storage unit 24. .
[Effect of the third embodiment]
As described above, according to the connection destination determination process of the present embodiment, as in the connection destination determination process of the first embodiment, the mobile communication terminal 5 that should receive data necessary at an appropriate timing is used as the connection destination. Can be determined.

  Moreover, according to the connection destination determination process of the present embodiment, wireless communication is performed among the mobile communication terminals 5 whose connection IDs are not stored in the storage unit 24 and capable of receiving beacons. The mobile communication terminal 5 having the largest number of times the device 20 itself has received a beacon is determined as the connection destination terminal 5.

According to such a wireless communication device 20, the mobile communication terminal 5 with good communication quality with the wireless communication device 20 can be determined as the connection destination terminal 5.
[Other Embodiments]
As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, In the range which does not deviate from the summary of this invention, it is possible to implement in various aspects.

  For example, in the communication system 1 according to the first to third embodiments, the wireless communication device 20 uses the so-called passive method as the method for detecting the connection destination terminal 5, but detects the connection destination terminal 5. The method is not limited to the passive method, and may be an active method. That is, the active radio communication apparatus 20 transmits a request signal for requesting a response including at least the connection ID to the mobile communication terminal 5 within the communication range. Then, the reception level of the response from each mobile communication terminal 5 that has received the request signal is equal to or higher than the specified threshold value, and the connection ID included in the response is not stored in the storage unit 24 as the connection history. The corresponding mobile communication terminal 5 may be determined as the connection destination terminal 5.

  Further, in the communication system 1 of the first to third embodiments, the IEEE 802.15.4, which is a well-known short-range wireless standard, is used as a communication method between the mobile communication terminal 5 and the wireless communication device 20. ZigBee (ZigBee (registered trademark)) standardized by the above is used, but the communication method is not limited to this. That is, any method may be used as long as it is communication between the wireless communication device 20 and the mobile communication terminal 5 connected via a wireless network. Further, in the present invention, the connection target of the wireless communication device 20 may be the mobile communication terminal 5 itself. In this case, the connection ID may be identification information for identifying the mobile communication terminal 5 itself.

Furthermore, the communication between the mobile communication terminal 5 and the wireless communication device 20 is not limited to communication using radio waves, but may be communication using light waves.
Further, in the transmission processing in the wireless communication device 20 of the first to third embodiments, all steps from S430 to S450 are executed. However, in the transmission processing in the present invention, S430 is omitted. Alternatively, S440 may be omitted, S450 may be omitted, or two of the steps from S430 to S450 may be omitted. That is, in the transmission process according to the present invention, it is only necessary that at least one of the steps from S430 to S450 is executed. Furthermore, S460 may be omitted in the transmission processing in the present invention.

  In the first to third embodiments, the data transmitted by the wireless communication device 20 includes the regulation information. However, the data transmitted by the wireless communication device 20 includes the regulation information. Not necessary. That is, any data may be transmitted by the wireless communication device 20.

  By the way, in the said embodiment, although the mobile communication terminal 5 was mounted in the motor vehicle AM, the object by which the mobile communication terminal 5 in this invention is mounted is not restricted to the motor vehicle AM. That is, the object on which the mobile communication terminal 5 of the present invention is mounted may be any object as long as it is a mobile object such as a ship, an aircraft, a motorcycle, or a bicycle.

  In addition, the aspect which abbreviate | omitted a part of structure of the said embodiment as long as the subject could be solved is also embodiment of this invention. Further, an aspect configured by appropriately combining the above embodiment and the modification is also an embodiment of the present invention. Moreover, all the aspects which can be considered in the limit which does not deviate from the essence of the invention specified by the wording described in the claims are the embodiments of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Communication system 5 ... Mobile communication terminal (connection destination terminal) 7 ... Wireless communication circuit 9 ... Control part 11 ... Antenna 20 ... Wireless communication apparatus 22 ... Sensing part 24 ... Memory | storage part 26 ... Wireless communication circuit 28 ... Control part 29 ... Antenna 30 ... Timekeeping section

Claims (13)

A wireless communication device (20) for transmitting data by wireless communication to a connection destination terminal that is one mobile communication terminal determined from among mobile communication terminals (5) mounted on each mobile body,
Receiving means (S210) for receiving an information signal repeatedly transmitted from each of the mobile communication terminals and including connection identification information associated with each mobile communication terminal and identifying a connection target of the wireless communication device;
The determination target information, which is connection identification information included in the information signal received by the receiving means, is not stored in the history storage unit that stores connection identification information corresponding to the mobile communication terminal that has transmitted the data in the past. Connection destination determination means (S220 to S260, S263, S267, S270, S272) for executing determination control for determining the mobile communication terminal corresponding to the determination target information as the connection destination terminal;
Transmission means (S410 to S460) for transmitting the data to the connection destination terminal determined by the connection destination determination means;
When transmission of data to the connection destination terminal is completed by the transmission means, transmission destination storage means (S510 to S540) that stores a connection history including connection identification information corresponding to the connection destination terminal in the history storage unit (24). And a wireless communication apparatus. The transmission destination storage means
Storing the connection time at which data is transmitted to the connection destination terminal and the connection identification information of the connection destination terminal in the history storage unit as the connection history,
History erasure means (S610 to S640) for erasing the connection history from the history storage unit when a specified time or more has elapsed from the connection time included in the connection history stored in the history storage unit.
The wireless communication apparatus according to claim 1, further comprising: The transmission means includes
Comprising data generation means for repeatedly generating the data;
The transmission destination storage means
The wireless communication apparatus according to claim 1, wherein a connection history is stored in the history storage unit for each of the data generated by the data generation unit. The connection destination determining means includes
If the determination target information of each information signal received by the receiving means during the first period specified in advance is not stored in the history storage unit, it is associated with the connection identification information included in the information signal, Level storage means (S230, S243) for storing the reception level of the information signal in the identification information storage unit (24),
Determining the mobile communication terminal corresponding to the connection identification information associated with the highest reception level among the reception levels stored in the identification information storage unit by the level storage means as the connection destination terminal; The wireless communication apparatus according to any one of claims 1 to 3, wherein the wireless communication apparatus is executed as the determination control. The connection destination determining means includes
If the determination target information of the information signal received by the receiving unit during the second period specified in advance is not stored in the history storage unit, mobile communication corresponding to connection identification information included in the information signal A number of times storage means (S230, S243) for storing the number of times of reception of the information signal from the terminal in the identification information storage unit (24);
Determining as the connection destination terminal the mobile communication terminal corresponding to the connection identification information having the largest number of receptions stored in the identification information storage unit by the number storage means, and executing as the determination control The wireless communication device according to any one of claims 1 to 3. The connection destination determining means includes
If the reception level of the information signal received by the receiving means is equal to or lower than a predetermined value, the connection identification information included in the information signal is excluded from the determination target information and the determination control is not executed. The wireless communication device according to claim 1, wherein the wireless communication device is a wireless communication device. The transmission means includes
A counter (S420) for counting the number of times the data is transmitted each time the data is transmitted;
The transmission of the data to the connection destination terminal determined by the connection destination determination unit is completed if the number of transmissions counted by the counting unit is equal to or greater than a predetermined number of times specified in advance. The wireless communication device according to any one of claims 1 to 6. The transmission means includes
The transmission of the data to the connection destination terminal is completed when a reception confirmation indicating that the data has been successfully received from the connection destination terminal is received after the transmission of the data. The radio | wireless communication apparatus as described in any one of Claim 1-7. The counting means increments the number of transmissions of the data after transmitting the data,
The wireless communication apparatus according to claim 7, further comprising: a specified number of times setting unit (S310 to S350) that sets a representative value of the number of transmissions counted by the counting unit as the specified number of times. The transmission means includes
The connection destination terminal includes connection identification information corresponding to the connection destination terminal determined by the connection destination determination unit, and the reception level of the information signal received by the reception unit is less than a predetermined specified level. The wireless communication device according to any one of claims 1 to 9, wherein the transmission of the data to the device is completed. The transmission destination storage means
When the transmission means completes the transmission of data to the connection destination terminal, the transmission means includes release means (S510) for outputting a release request for requesting the connection destination terminal to release the connection,
Receiving a release permission for permitting the release of the connection from the connection destination terminal that has received the release request from the release means, storing a connection history including connection identification information of the connection destination terminal in the history storage unit. The wireless communication apparatus according to any one of claims 1 to 10, wherein the wireless communication apparatus is characterized. Data transmission method in wireless communication device (20) for wirelessly transmitting data to a connection destination terminal which is one mobile communication terminal determined from mobile communication terminals (5) mounted on each of the mobile objects Because
A reception procedure for receiving an information signal transmitted from each of the mobile communication terminals at a specified time interval and including connection identification information associated with each mobile communication terminal and identifying a connection target of the radio communication device (S210),
The determination target information that is connection identification information included in the information signal received in the reception procedure is not stored in the history storage unit that stores connection identification information corresponding to the mobile communication terminal that has transmitted the data in the past. A connection destination determination procedure (S220 to S260, S263, S267, S270, S272) for determining the mobile communication terminal corresponding to the determination target information as the connection destination terminal;
A transmission procedure (S410 to S460) for transmitting the data to the connection destination terminal determined in the connection destination determination procedure;
When transmission of data to the connection destination terminal is completed in the transmission procedure, a transmission destination storage procedure (S510 to S540) that stores a connection history including connection identification information corresponding to the connection destination terminal in the history storage unit (24). And a data transmission method. A computer included in a wireless communication device (20) that transmits data by wireless communication to a connection destination terminal that is one mobile communication terminal determined from the mobile communication terminals (5) mounted on each of the mobile objects. A program to be executed,
A reception procedure for receiving an information signal transmitted from each of the mobile communication terminals at a specified time interval and including connection identification information associated with each mobile communication terminal and identifying a connection target of the radio communication device (S210),
The determination target information that is connection identification information included in the information signal received in the reception procedure is not stored in the history storage unit that stores connection identification information corresponding to the mobile communication terminal that has transmitted the data in the past. A connection destination determination procedure (S220 to S260, S263, S267, S270, S272) for determining the mobile communication terminal corresponding to the determination target information as the connection destination terminal;
A transmission procedure (S410 to S460) for transmitting the data to the connection destination terminal determined in the connection destination determination procedure;
When transmission of data to the connection destination terminal is completed in the transmission procedure, a transmission destination storage procedure (S510 to S540) that stores a connection history including connection identification information corresponding to the connection destination terminal in the history storage unit (24). ) Is executed by the computer.