US-12621701-B2 - Wireless communication data transmission device, data transmission method, and storage medium storing data transmission program

US12621701B2US 12621701 B2US12621701 B2US 12621701B2US-12621701-B2

Abstract

A data transmission device includes a wireless communication unit that wirelessly communicates with an external communication device, a travel route information acquirer that acquires a future travel route of a moving object, a travel route, a propagation environment information acquirer that acquires propagation environment information of a radio wave propagation path used in wireless communication, a speed information acquisition unit that acquires the moving speed of a moving object, and a converter that converts a relationship between the travel route and propagation environment information into a plurality of data slots each defined by the communication speed per unit time; a transmission instructor that instructs the wireless communication unit to transmit the data allocated to the data slot.

Inventors

Shigeki Kawai
Tsuneo Nakata

Assignees

DENSO CORPORATION

Dates

Publication Date: 20260505
Application Date: 20230321
Priority Date: 20200925

Claims (8)

1 . A data transmission device mounted in a moving object, comprising: a wireless communication unit performing wireless communication with an external communication device; a data storage unit storing data to be transmitted from the wireless communication unit; a travel route information acquisition unit acquiring a future travel route of the moving object; a propagation environment information acquisition unit acquiring propagation environment information of a radio wave propagation path used in the wireless communication on the future travel route; a speed information acquisition unit acquiring a moving speed of the moving object; a converter converting a relationship between the future travel route and the propagation environment information into a plurality of data slots each defined by a communication speed per unit time based on the moving speed; an allocation unit allocating the data to at least one of the data slots in an order from a data slot among the at least one of the data slots having a highest communication speed; a transmission instruction unit instructing the wireless communication unit to transmit the data allocated to a data slot among the at least one of the data slots that corresponds to a current time; and a traffic signal information acquirer that acquires a remaining time of a stop signal of a traffic signal; wherein: the plurality of data slots is composed of multiple types of slots having respectively different communication speeds along the future travel route; and when the moving object is stopped according to the stop signal of the traffic signal, the converter performs the converting by assuming that the moving speed of the moving object increases at a constant rate up to a speed limit of the future travel route after elapse of the remaining time.
2 . The data transmission device according to claim 1 , wherein the converter and the allocation unit perform conversion and allocation at each unit time.
3 . The data transmission device according to claim 1 , wherein the converter and the allocation unit perform conversion and allocation when the moving speed changes by a predetermined threshold value or more.
4 . The data transmission device according to claim 1 , wherein a transmission time limit is set for the data, and the allocation unit allocates the data to at least one of the data slots within the transmission time limit.
5 . The data transmission device according to claim 4 , wherein when the data includes a plurality of data items, the allocation unit allocates one of the data items having the transmission time limit closest to the current time to at least one of the data slots that is earlier than another of the data slots to which another data item is allocated.
6 . The data transmission device according to claim 1 , wherein the propagation environment information includes a first communication speed and a second communication speed slower than the first communication speed, and the transmission instruction unit instructs transmission of the data at the first communication speed when the data has a high priority and instructs transmission of the data at the second communication speed otherwise.
7 . A data transmission method performed by a data transmission device mounted in a moving object and having a wireless communication unit that performs wireless communication with an external communication device, the data transmission method comprising steps of: acquiring a future travel route of the moving object; acquiring propagation environment information of a radio wave propagation path used in the wireless communication on the future travel route; obtaining a moving speed of the moving object; converting a relationship between the future travel route and the propagation environment information into a plurality of data slots each defined by a communication speed per unit time based on the moving speed; allocating data to at least one of the data slots in order from a data slot among the at least one of the data slots having a highest communication speed; instructing the wireless communication unit to transmit the data allocated to a data slot among the at least one of the data slots that corresponds to a current time; and acquiring a remaining time of a stop signal of a traffic signal; wherein: the plurality of data slots are composed of multiple types of slots having respectively different communication speeds along the future travel route; and when the moving object is stopped according to the stop signal of the traffic signal, the converting is performed by assuming that the moving speed of the moving object increases at a constant rate up to a speed limit of the future travel route after elapse of the remaining time.
8 . A non-transitory, computer readable, tangible storage medium storing a data transmission program executable by a data transmission device mounted in a moving object and having a wireless communication unit that performs wireless communication with an external communication device, the program comprising instructions, when executed by the data transmission device, causing the data transmission device to perform steps of: acquiring a future travel route of the moving object; acquiring propagation environment information of a radio wave propagation path used in the wireless communication on the future travel route; obtaining a moving speed of the moving object; converting a relationship between the future travel route and the propagation environment information into a plurality of data slots each defined by a communication speed per unit time based on the moving speed; allocating data to at least one of the data slots in order from a data slot having a highest communication speed; instructing the wireless communication unit to transmit the data allocated to a data slot among the data slots that corresponds to a current time; and acquiring a remaining time of a stop signal of a traffic signal; wherein: the plurality of data slots are composed of multiple types of slots having respectively different communication speeds along the future travel route; and when the moving object is stopped according to the stop signal of the traffic signal, the converting is performed by assuming that the moving speed of the moving object increases at a constant rate up to a speed limit of the future travel route after elapse of the remaining time.

Description

CROSS REFERENCE TO RELATED APPLICATION This application is a continuation application of International Patent Application No. PCT/JP2021/024395 filed on Jun. 28, 2021, which designated the U.S. and claims the benefit of priority from Japanese Patent Application No. 2020-161477 filed on Sep. 25, 2020. The entire disclosure of all of the above application is incorporated herein by reference. TECHNICAL FIELD The present application relates to a data transmission device or the like that transmits data based on a communication plan for efficient data transmission, and is mainly a data transmission device or the like mounted on a moving object, or a data transmission device and the like realized by a server device and the like that performs communication directly or indirectly with a moving object. BACKGROUND With the spread of wireless communication, opportunities to communicate using wireless communication are increasing in various places. In particular, in moving objects such as automobiles, attention is being paid to techniques for performing driving assistance and automatic driving control using high-capacity cellular communication, V2X such as vehicle-to-vehicle communication and road-to-vehicle communication. As a result, a vehicle is equipped with a communication function, and so-called connectivity of the vehicle has been promoted. Here, in wireless communication, it is known that radio waves interfere with each other, causing the strength and weakness of the transmission level and reception level of radio waves depending on the location, and such a phenomenon is generally called fading. Since moving objects such as automobiles are assumed to be moving thereby causing fluctuation of the communication quality along with the move of the moving objects, a countermeasure for the fading may be established if the communication quality at a certain location is known in advance. For example, there has been known a communication resource map that indicates the correspondence relationship between a point and an amount of communication resource that is estimated to be available for communication at that point. Further, prediction of communication quality along a communication path using information acquired by statistically processing the relationship between position and communication speed has been also known. SUMMARY A data transmission device according to one aspect of the present disclosure is mounted in a moving object, including: a wireless communication unit that performs wireless communication with an external communication device;a data storage unit that stores data to be transmitted from the wireless communication unit;a travel route information acquisition unit that acquires a future travel route of the moving object;a propagation environment information acquisition unit that acquires propagation environment information of a radio wave propagation path used in the wireless communication on the travel route;a speed information acquisition unit that acquires a moving speed of the moving object;a converter that converts a relationship between the travel route and the propagation environment information into a plurality of data slots each defined by a communication speed per unit time based on the moving speed;an allocator that allocates the data to at least one of the data slots in an order from a data slot among the at least one data slots having a highest communication speed; anda transmission instructor that instructs the wireless communication unit to transmit the data allocated to a data slot among the at least one of the data slots that corresponds to a current time. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an overall configuration of an embodiment of the present disclosure; FIG. 2 is a block diagram showing a configuration example of a data transmission device according to a first embodiment of the present disclosure; FIG. 3 is an explanatory diagram for explaining an operation of a radio wave environment information acquisition unit and a converter of the data transmission device according to the first and second embodiments of the present disclosure; FIG. 4 is an explanatory diagram for explaining the operation of an allocator of the data transmission device according to the first and second embodiments of the present disclosure; FIG. 5 is a flowchart showing the operation of the data transmission device according to the first embodiment of the present disclosure; FIG. 6 is a block diagram showing a configuration example of the data transmission device according to the second embodiment of the present disclosure; FIG. 7 is a flowchart showing the operation of the data transmission device according to the second embodiment of the present disclosure; and FIG. 8 is a diagram illustrating an overall configuration of a modification of the second embodiment of the present disclosure. DESCRIPTION OF EMBODIMENTS Next, a relevant technology will be described only for understanding the