JP6587037B1 - COMMUNICATION DEVICE, COMMUNICATION METHOD, AND PROGRAM - Google Patents

Abstract

Provided are a communication device, a communication method, and a program capable of reducing a reception error on the receiving side as much as possible even when used for an application involving movement. A communication apparatus capable of transmitting position information based on a LPWA (Low Power Wide Area) communication method, a position information acquisition unit for acquiring position information, and movement of the communication apparatus after acquisition of position information It is a communication apparatus which has the movement determination part which determines the presence or absence of, and the transmission control part which controls transmission of a positional information based on the determination result in a movement determination part. [Selection] Figure 2

Description

  The present invention relates to a communication device, a communication method, and a program.

  2. Description of the Related Art Conventionally, a technique for optimizing wireless communication by a communication apparatus that involves movement has been proposed. For example, Patent Literature 1 below discloses a technique for searching for a connection destination of a wireless network when a stationary mobile terminal is detected using a movement detection unit such as an acceleration sensor. Thereby, since the search operation of the wireless network is not performed during movement, power consumption can be reduced compared to the case where the search operation of the connection destination is performed during movement.

  By the way, in recent years, LPWA (Low Power Wide Area) (power saving wide area) attracts attention as a communication method between an IoT (Internet of Things) device and a server. LPWA is very slow compared to cellular lines such as 3G lines and 4G lines, and wireless LAN (Local Area Network), but LPWA can transmit over a wide range, has a narrow frequency bandwidth, and consumes very much power. It has the characteristic that there are few, and is suitable for the sensor network etc. which transmit many small data from several places.

  Communication standards based on LPWA include, for example, Sigfox (sub-GHz band (866 MHz band, 915 MHz band / 920 MHz band), maximum transmission speed of about 100 bps, transmission distance of about several tens of kilometers), LoRa (sub-GHz band, maximum transmission) The speed is about 250 kbps, the transmission distance is about 10 km at maximum, Wi-Fi HaLow (sub GHz band, the maximum transmission speed is about 150 kbps, the transmission distance is about 1 km), and Wi-SUN (sub GHz band, the maximum transmission speed is 800 kbps. Transmission distance is about 1 km), RPMA (2.4 GHz band, maximum transmission speed is 40 kbps, maximum transmission distance is about 20 km), Flexnet (280 MHz band, maximum transmission speed is 10 kbps, maximum transmission distance is about 20 km), NB-IoT Etc.

JP 2009-44309 A

  However, a communication standard suitable for such an IoT device is basically not suitable for use in a communication apparatus that involves movement as described above. This is because when such a communication standard is applied to wireless communication in a moving IoT device (for example, an IoT device used for tracking position information), frequency shift due to Doppler shift is caused by the narrowband wireless communication as described above. Furthermore, since the communication speed is slow and it takes time to transmit once (for example, 7 to 8 seconds in the case of Sigfox), there is a problem that the reception error rate becomes high on the reception side.

  The present invention has been made in view of such circumstances, and provides a communication device, a communication method, and a program that can reduce reception errors on the reception side as much as possible even when used in applications involving movement. It is in.

In order to solve the problems described above, the present invention provides:
A communication device capable of transmitting position information based on a LPWA (Low Power Wide Area) communication method,
A location information acquisition unit for acquiring location information;
A movement determination unit that determines the presence or absence of movement of the communication device after acquisition of the position information by the position information acquisition unit;
Have a transmission control unit for controlling the transmission of position information based on the result of the determination by the movement determination unit,
The movement determination unit determines whether or not there is movement during the transmission of the position information based on the first acceleration information acquired before the transmission of the position information and the second acceleration information acquired after the transmission of the position information.
The transmission control unit is a communication device that performs control so that the same position information as the position information is retransmitted when the movement determination unit determines that there is movement .

In the present invention, the movement determination unit determines the presence or absence of movement before transmitting the position information,
The transmission control unit preferably performs control so that the position information is transmitted when the movement determination unit determines that there is no movement.

In the present invention,
The movement determination unit determines whether or not there is movement after transmitting the position information,
The transmission control unit preferably performs control so that the position information is retransmitted when the movement determination unit determines that there is movement.

In the present invention,
It has a movement detector that detects the movement of the communication device,
The position information acquisition unit preferably acquires the position information when movement is detected by the movement detection unit.

A communication method capable of transmitting position information based on a LPWA (Low Power Wide Area) communication method,
The location information acquisition unit acquires location information,
The movement determination unit determines the presence or absence of movement of the communication device after acquisition of the position information by the position information acquisition unit,
The transmission control unit controls the transmission of the position information based on the determination result by the movement determination unit ,
The movement determination unit determines whether or not there is movement during the transmission of the position information based on the first acceleration information acquired before the transmission of the position information and the second acceleration information acquired after the transmission of the position information.
The transmission control unit is a communication method for performing control so that the same position information as the position information is retransmitted when the movement determination unit determines that there is movement .

A communication method capable of transmitting position information based on a LPWA (Low Power Wide Area) communication method,
The location information acquisition unit acquires location information,
The movement determination unit determines the presence or absence of movement of the communication device after acquisition of the position information by the position information acquisition unit,
The transmission control unit controls the transmission of the position information based on the determination result by the movement determination unit ,
The movement determination unit determines whether or not there is movement during the transmission of the position information based on the first acceleration information acquired before the transmission of the position information and the second acceleration information acquired after the transmission of the position information.
The transmission control unit is a program that causes a computer to execute a communication method for performing control so that the same position information as the position information is retransmitted when the movement determining unit determines that there is movement .

  According to the present invention, reception errors on the receiving side can be reduced as much as possible even when used in applications involving movement. In addition, the content of this invention is not limited by the effect described in this specification.

It is a block diagram which shows the structural example of the IoT device which has the radio | wireless communication module concerning 1st Embodiment. It is a functional block diagram which shows the structural example of the radio | wireless communication module concerning 1st Embodiment. It is a flowchart which shows an example of the flow of the process performed in 1st Embodiment. It is a figure for demonstrating an example of the acquisition timing of the positional information concerning 1st Embodiment. It is a figure for demonstrating an example of the transmission timing of the positional information concerning 1st Embodiment. It is a figure for demonstrating an example of the transmission timing of the positional information concerning 1st Embodiment. It is a functional block diagram for showing the example of composition of the radio communications module concerning a 2nd embodiment. It is a flowchart which shows an example of the flow of the process performed in 2nd Embodiment.

Hereinafter, embodiments and the like of the present invention will be described with reference to the drawings. The description will be given in the following order.
<First Embodiment>
<Second Embodiment>
<Modification>
The embodiments described below are preferred specific examples of the present invention, and the contents of the present invention are not limited to these embodiments.

<First Embodiment>
[Configuration example of IoT device]
FIG. 1 shows a configuration example of an IoT device (IoT device 1) according to the first embodiment. As shown in FIG. 1, the communication apparatus (wireless communication module 6) according to the first embodiment of the present invention is mounted on the IoT device 1. Specifically, the IoT device 1 is a small GPS (Global Positioning System) tracker excellent in portability, and is connected to a wireless network, and a server in a remote location is used to store position information (positioning information) of the IoT device 1 It is configured to be able to transmit to a device or the like. The location information transmitted from the IoT device 1 is appropriately used by the server device by a method according to the application or contract. The IoT device 1 is attached to or detached from an article such as a person, an animal such as a pet, a key, a smart phone, or a bag.

  As shown in the figure, the IoT device 1 includes an acceleration sensor 2, a GPS receiver 3, a temperature / humidity / atmospheric pressure sensor 4, a notification LED (Light Emitting Diode) 5, a wireless communication module 6, a power supply 7, and a power switch 8. Yes. The acceleration sensor 2 detects a change in motion in a linear direction accompanying the movement of the IoT device 1 as acceleration, and outputs the detection result as acceleration information. Specifically, the acceleration sensor 2 detects accelerations in the three directions of the XYZ axes orthogonal to each other, and outputs information representing the acceleration in each direction as acceleration information. Further, when the acceleration sensor 2 detects an acceleration accompanying the movement of the IoT device 1, the acceleration sensor 2 outputs notification information notifying that effect.

  The GPS receiver 3 receives radio waves from GPS satellites, performs positioning using the radio waves, generates position information based on the positioning results, and outputs the position information. The temperature / humidity / barometric pressure sensor 4 detects the temperature / humidity / barometric pressure of the place where the IoT device 1 is located, and outputs the detection result as temperature / humidity / barometric pressure information.

  The acceleration sensor 2, the GPS receiver 3, and the temperature / humidity / pressure sensor 4 are respectively connected to the wireless communication module 6. The wireless communication module 6 receives the acceleration information, notification information, position information, and temperature / humidity / pressure information described above. Each can be output.

  The notification LED 5 is for visually informing the user of the state of the IoT device 1. Specifically, the notification LED 5 is connected to the wireless communication module 6 as shown in the figure, and under the control of the wireless communication module 6, an on / off state of a power switch 8 (described later), an operating state of the wireless communication module 6, and the like. Notify by lighting status.

  The wireless communication module 6 is configured by a circuit board on which an electronic component such as SoC (System-on-a-chip) is mounted, for example, and is based on the LPWA suitable for the IoT device 1 described above, specifically, the Sigfox wireless standard. Compliant communication is configured. Of course, not only Sigfox but also other LPWA communication standards described above can be applied.

  The power source 7 is a power supply source to each element constituting the IoT device 1. Specifically, the power source 7 is configured by a coin battery, a button battery, a dry battery, or the like suitable for use in a small portable device. The power source 7 may be configured by a secondary battery (for example, a lithium ion battery) that can be charged via a charging port such as a USB (Universal Serial Bus). The power switch 8 is a switch for switching power on / off of the IoT device 1.

  By the way, the above-described wireless communication module 6 is equipped with application software for a GPS tracker. As shown in FIG. 2, the wireless communication module 6 includes a storage unit 61, a sensor information acquisition unit 62, a position information acquisition unit 63, a sleep processing unit 64, and a movement detection unit 65 that function when the program is executed by the software. A movement determination unit 66, a transmission control unit 67, and a communication unit 68.

  The storage unit 61 stores various information such as information used in processing to be described later, a program, and the like in a memory (not shown), and reads out from the memory. Specifically, the storage unit 61 stores acceleration information acquired by a sensor information acquisition unit 62 described later. The sensor information acquisition unit 62 acquires information from each sensor such as the acceleration sensor 2 and the temperature / humidity / barometric pressure sensor 4. Specifically, the sensor information acquisition unit 62 acquires the above-described acceleration information from the acceleration sensor 2 every predetermined period (for example, 200 milliseconds) using timekeeping information such as a timer. The sensor information acquisition unit 62 acquires the notification information output from the acceleration sensor 2 in an interrupted manner.

  The position information acquisition unit 63 acquires position information from the GPS receiver 3. Specifically, the position information acquisition unit 63 basically acquires position information at a timing every predetermined period (for example, several minutes to several tens of minutes) using timekeeping information such as a timer. The acquisition of the position information will be described in detail later.

  The sleep processing unit 64 operates the wireless communication module 6 in the sleep mode. Here, the sleep mode refers to a power saving state in which processing with high power consumption such as positioning by the GPS receiver 3 and transmission by the communication unit 68 described later is not performed.

  The movement detection unit 65 detects movement of the IoT device 1 including the wireless communication module 6. Specifically, the movement detection unit 65 determines that the movement of the IoT device 1 has been detected when the sensor information acquisition unit 62 receives notification information from the acceleration sensor 2.

  The movement determination unit 66 determines whether or not the IoT device 1 including the wireless communication module 6 has moved. Specifically, the movement determination unit 66, when the acceleration information is acquired by the sensor information acquisition unit 62, the previous acceleration information stored in the storage unit 61 (specifically, the three-axis acceleration described above). The difference between the base XYZ value in the sensor) and the acquired acceleration information (specifically, the XYZ value after a certain time has elapsed in the above-described triaxial acceleration sensor) is calculated, and the difference is less than a predetermined threshold value. Is determined to be in a stationary state (no movement), and if it is equal to or greater than the threshold, it is determined to be in a moving state (with movement). For example, this movement is a movement that causes a reception error on the receiving side. This threshold value is appropriately set depending on the usage environment of the IoT device 1 and the like.

  The transmission control unit 67 controls transmission by the communication unit 68. The communication unit 68 is connected to a wireless network by wireless communication based on the above-described LPWA wireless standard, and transmits position information to the outside of the IoT device 1 via the antenna ANT. As the antenna ANT, an antenna built in the wireless communication module 6 may be used according to the communication state, or an external antenna with higher gain may be used.

[Flow of processing performed in the first embodiment]
Next, an example of the flow of processing by the above-described wireless communication module 6 will be described with reference to FIG. When the user switches the power switch 8 of the IoT device 1 shown in FIG. 1 from OFF to ON, power is supplied to the wireless communication module 6 from the power supply 7 and the process shown in FIG. 3 is started. This process ends when the power switch 8 is turned off again (YES in step S1).

  When the power switch 8 is on (NO in step S1), the wireless communication module 6 is set to the sleep mode by the sleep processing unit 64 (step S2). Then, during the operation in the sleep mode, it is determined whether or not a predetermined timing for releasing the sleep mode has come (step S3). The predetermined timing for canceling the sleep mode is set to a timing for each predetermined period (for example, several minutes to several tens of minutes) in which position information is basically acquired from the GPS receiver 3 described above. For example, when it is set every 2 minutes, the timing every 2 minutes is determined from the timing when the power is turned on and the timing when the power is turned on.

  When it is determined in step S3 that the predetermined timing is not reached (NO), the movement detection unit 65 determines whether or not movement of the IoT device 1 is detected (step S4). If it is determined in step S4 that no movement is detected (NO), the process returns to step S3. On the other hand, if it is determined that movement has been detected (YES), flag information indicating that movement has been detected is stored in the storage unit 61 (step S5), and then the process returns to step S3. When this movement is detected, it is preferable to stop obtaining the notification information from the acceleration sensor 2 until the next sleep mode release timing. Thereby, electric power consumption can be reduced compared with the case where notification information is continuously received from the acceleration sensor 2 after detection.

  When it is determined that the predetermined timing is reached (YES) in step S3, it is determined whether or not the movement has been detected (step S6). Specifically, if the flag information is stored in the storage unit 61, it is determined that the movement is detected, and if it is not stored, it is determined that the movement is not detected. If it is determined in step S6 that movement has been detected (YES), the GPS receiver 3 is activated by the position information acquisition unit 63, and position information is acquired from the GPS receiver 3 (step S7). .

  That is, as shown in FIG. 4, in the wireless communication module 6, the sleep mode cancellation determination is made every predetermined period (every 2 minutes in the illustrated example). When the movement of the IoT device 1 is detected during the sleep mode, the sleep mode is canceled at the next sleep mode release determination timing, and position information is acquired from the GPS receiver 3. On the other hand, if no movement is detected, position information is not acquired.

  After the position information is acquired in step S7, the movement determination unit 66 determines whether or not the IoT device 1 is in a stationary state (step S8). If it is determined in step S8 that the vehicle is not stationary (NO), it is determined whether or not a timeout has occurred (step S9). The time for the timeout is appropriately set (for example, 3 seconds) in advance based on the sleep mode release determination interval or the like. If it is determined in step S9 that there is no timeout (NO), the process returns to step S8.

  If it is determined in step S8 that it is in a stationary state (YES) and if it is determined in step S9 that it is timed out (YES), the position information acquired previously is transmitted from the transmission control unit 67 to the communication unit 68. The position information is transmitted by the communication unit 68 (step S10). If it is determined in step S9 that a timeout has occurred (YES), notification of an error or the like may be performed without transmitting this position information, but there is a possibility that no reception error will occur on the receiving side. Because there is, transmission is performed here.

  That is, as shown in FIG. 5, in the wireless communication module 6, after the position information is acquired, the acceleration information is acquired from the acceleration sensor 2 every predetermined period (in the illustrated example, every 200 milliseconds). The difference between the obtained acceleration information and the acceleration information acquired immediately before the acceleration information is calculated. If the difference is less than the threshold value, it is determined that the camera is stationary and position information is transmitted. On the other hand, if it is equal to or greater than the threshold value, it is determined that it is not in a stationary state (is in a moving state), and position information is not transmitted. As shown in FIG. 6, if the state in which the difference exceeds the threshold value continues until timeout (in the example shown, acceleration information acquisition starts for 3 seconds), position information is transmitted at the time of timeout. . In addition, when position information can be acquired quickly and position information is updated, the latest position information may be transmitted in a stationary state.

  Then, after the transmission of the position information in step S10, as shown in FIG. 3, preprocessing for shifting to the sleep mode is performed (step S11). Specifically, a process for placing the acceleration sensor 2 and the GPS receiver 3 in a standby state is performed. In addition, also when it determines with there being no detection of a movement in step S6 mentioned above (NO), the process of this step S11 is made. Then, after the process of step S11, the process returns to step S1.

  As described above, according to the wireless communication apparatus (wireless communication module 6) according to the first embodiment of the present invention, after the position information acquisition unit 63 acquires the position information, the movement determination unit 66 performs the wireless communication module. 6 is determined, and transmission of position information is controlled by the transmission control unit 67 based on the determination result. In this way, the presence / absence of movement is determined after the acquisition of the position information, and the transmission of the position information is controlled based on the determination result. Therefore, transmission control is performed according to the movement status of the wireless communication module 6 after the acquisition of the position information. be able to.

  In the present embodiment, the movement determination unit 66 determines whether or not the wireless communication module 6 has moved before transmitting the position information, and the transmission control unit 67 transmits the position information when it is determined that the wireless communication module 6 is stationary, that is, no movement. Therefore, it is possible to reduce the probability of receiving errors on the receiving side as compared with the case where the position information is immediately transmitted after being acquired. In addition, by appropriately setting the length of the period for determining the presence or absence of movement, even if the position information is transmitted after stopping, it is possible to prevent the position information from being significantly different. This is effective when the transmission control unit 67 controls transmission of information by the communication unit 68 that performs wireless communication using the LPWA communication method, as in the present embodiment.

  In the wireless communication module 6, when the movement detection unit 65 detects the movement of the wireless communication module 6, the position information acquisition unit 63 acquires the position information. Regardless of the case where the position information is acquired from the GPS receiver 3, the power consumption can be reduced.

<Second Embodiment>
Next, a wireless communication device (wireless communication module 6A) according to the second embodiment of the present invention will be described with reference to FIG. In the wireless communication module 6A shown in FIG. 7, the processing by the movement determination unit 66A and the transmission control unit 67A is the same as the processing by the movement determination unit 66 and the transmission control unit 67 of the wireless communication module 6 according to the first embodiment described above. Is different. Other points are the same as in the first embodiment described above. In the figure, the same or similar components as those in the first embodiment are denoted by the same reference numerals, and description thereof is simplified or omitted.

  Similar to the movement determination unit 66 in the first embodiment described above, the movement determination unit 66A determines whether or not the IoT device 1 has moved. The transmission control unit 67A controls transmission by the communication unit 68 in the same manner as the transmission control unit 67 in the first embodiment described above.

  Hereinafter, an example of the flow of processing performed by the wireless communication module 6A having the movement determination unit 66A and the transmission control unit 67A will be described with reference to FIG. Each process from step S21 to step S27 shown in FIG. 8 is the same as step S1 to step S7 shown in FIG. 3 described above, and the description thereof is omitted here.

  In the wireless communication module 6A, when position information is acquired in the same manner as in the first embodiment described above (step S27), the acceleration sensor 2 is then activated by the sensor information acquisition unit 62, and the acceleration sensor 2 Acceleration information is acquired (step S28). Then, the communication control unit 67A controls the communication unit 68 so that the position information acquired in step S27 is transmitted, and the communication unit 68 transmits the position information (step S29). Thus, in this embodiment, the stationary state is not determined before the transmission of the position information.

  Then, after the position information is transmitted in step S29, the movement determination unit 66A determines whether or not the IoT device 1 has moved (step S30). That is, the acceleration information is acquired from the acceleration sensor 2 by the sensor information acquisition unit 62, the difference between the acceleration information before the transmission of the position information acquired earlier and the newly acquired acceleration information is calculated, and the difference is predetermined. If it is greater than or equal to the threshold value, it is determined that it has moved, and if it is less than the threshold value, it is determined that it has not moved.

  If it is determined in step S30 that it has moved (YES), there is a high possibility that a reception error has occurred on the receiving side due to the movement. Therefore, in step S31, the position information transmitted in step S29 is transmitted again (retransmitted). For example, the position information is retransmitted three times to the server device or the like. The number of times that the location information is retransmitted (the number of retries) is set as appropriate depending on the contents of the contract with the communication carrier (transmission frequency limit, fee, etc.). As described above, when there is a movement when the position information is transmitted, the same position information is retransmitted by the communication unit 68 under the control of the transmission control unit 67A.

  After the position information is retransmitted a predetermined number of times, the process for shifting to the sleep mode described above is performed (step S32), and the process returns to step S21.

  As described above, according to the wireless communication device (wireless communication module 6A) according to the second embodiment of the present invention, the presence / absence of movement is determined after the acquisition of position information, as in the first embodiment. Since the transmission of the position information is controlled based on the determination result, the transmission control according to the movement status of the wireless communication module 6A after the position information is acquired can be performed.

  In the present embodiment, the movement determination unit 66A determines whether or not the wireless communication module 6 has moved after the transmission of the position information, and if it is determined that there is a movement (YES in step S30), the position information is received by the transmission control unit 67A. Since it is controlled to be retransmitted, the position information is retransmitted even when the wireless communication module 6A moves during transmission of the position information and there is a high possibility that a reception error will occur on the reception side. The occurrence of reception errors can be reduced as much as possible. This is particularly effective when the transmission control unit 67 controls transmission of information by the communication unit 68 that performs wireless communication using the LPWA communication method, as in the present embodiment.

  Similarly to the first embodiment, in the wireless communication module 6A, when the movement of the wireless communication module 6A is detected by the movement detection unit 65, the position information acquisition unit 63 acquires the position information. The power consumption can be reduced compared to the case where the position information is acquired from the GPS receiver 3 regardless of whether the wireless communication module 6A is moved.

<Modification>
The present invention is not limited to that described in the above-described embodiment, and various modifications can be made. For example, the process described in the first embodiment described above and the process described in the second embodiment may be combined. That is, the presence or absence of movement of the wireless communication module 6 may be determined before and after transmitting the position information, and the position information may be transmitted based on each determination result. Thereby, both the effects explained in the first embodiment and the second embodiment can be obtained.

  In addition, the detection of the movement of the wireless communication modules 6 and 6A by the movement detection unit 65 and the determination of the presence or absence of the movement of the wireless communication modules 6 and 6A by the movement determination units 66 and 66A are not limited to those described above. . For example, in the above-described example, every time acceleration information is acquired by the sensor information acquisition unit 62, the threshold value and the difference are compared to determine the presence or absence of movement, but the average value of the difference for a predetermined number of times is compared with the threshold value. Thus, the presence or absence of movement may be determined, or the presence or absence of movement may be determined based on whether or not the difference is continuously less than a predetermined number of times.

  Further, in each of the above-described embodiments, the transmission information transmitted from the wireless communication modules 6 and 6A is the position information. However, the present invention is not limited to this, and the temperature / humidity / atmospheric pressure information output from the temperature / humidity / atmospheric pressure sensor 4 is not limited thereto. Information for transmission may be used, and other sensor output information may be used as information for transmission. A combination of these information may be used as transmission information.

  In each of the above-described embodiments, the communication unit 68 is exemplified as one that performs wireless communication in conformity with the LPWA communication method. However, the communication method is particularly suitable as long as the same operation and effect can be obtained. For example, the other LPWA communication standards described above can be applied.

  Furthermore, each process executed by software in each of the above-described embodiments may be realized by hardware. Further, the present invention can be realized in an appropriate form such as a method, a program, a system, and a recording medium on which the program is recorded.

6, 6A Wireless communication module 62 Sensor information acquisition unit 63 Position information acquisition unit 65 Movement detection unit 66, 66A Movement determination unit 67, 67A Transmission control unit

Claims (5)

A communication device capable of transmitting position information based on a LPWA (Low Power Wide Area) communication method,
A position information acquisition unit for acquiring the position information;
A movement determination unit that determines the presence or absence of movement of the communication device after acquisition of the position information by the position information acquisition unit;
Based on the result of determination by the movement determining section to have a transmission control unit for controlling transmission of the position information,
Based on the first acceleration information acquired before transmission of the position information and the second acceleration information acquired after transmission of the position information, the movement determination unit determines whether or not there is movement during transmission of the position information. Judgment,
The transmission control unit is a communication device that controls to retransmit the same position information as the position information when the movement determination unit determines that there is a movement . The movement determination unit determines presence / absence of movement before transmission of the position information based on the first acceleration information ;
The communication apparatus according to claim 1, wherein the transmission control unit controls the position information to be transmitted when the movement determination unit determines that there is no movement. A movement detection unit for detecting movement of the communication device;
The position information acquisition unit, a communication device according to claim 1 or 2 moved by the movement detection unit acquires the position information when it is detected. A communication method capable of transmitting position information based on a LPWA (Low Power Wide Area) communication method,
A position information acquisition unit acquires the position information;
The movement determination unit determines whether the communication device has moved after the position information acquisition unit acquires the position information,
A transmission control unit controls transmission of the position information based on a determination result by the movement determination unit ,
Based on the first acceleration information acquired before transmission of the position information and the second acceleration information acquired after transmission of the position information, the movement determination unit determines whether or not there is movement during transmission of the position information. Judgment,
The transmission method, wherein the transmission control unit performs control so that the same position information as the position information is retransmitted when the movement determination unit determines that there is a movement . A communication method capable of transmitting position information based on a LPWA (Low Power Wide Area) communication method,
A position information acquisition unit acquires the position information;
The movement determination unit determines whether the communication device has moved after the position information acquisition unit acquires the position information,
A transmission control unit controls transmission of the position information based on a determination result by the movement determination unit ,
Based on the first acceleration information acquired before transmission of the position information and the second acceleration information acquired after transmission of the position information, the movement determination unit determines whether or not there is movement during transmission of the position information. Judgment,
The transmission control unit is a program that causes a computer to execute a communication method for performing control so that the same position information as the position information is retransmitted when the movement determination unit determines that there is movement .

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