JP4821167B2 - Mobile communication system - Google Patents

Description

  The present invention relates to a mobile communication system, and more particularly, to a mobile communication system that performs large-capacity data communication when a vehicle is stopped.

  Road-to-vehicle communication technology such as DSRC (Dedicated Short Range Communication) is being developed as a communication technology indispensable for realizing ITS (Intelligent Road Traffic System).

  For example, Patent Document 1 describes that when large-capacity data is transmitted between a roadside device and an in-vehicle device, the vehicle is kept stationary by using a restraint device during data transfer so as not to move. ing.

Patent Document 2 describes a cruise control device and a lane departure warning device for recognizing a traveling environment of a vehicle and controlling a traveling operation.
JP 2003-85607 A Japanese Patent No. 3548684

  Since the vehicle described in Patent Document 1 is prohibited from traveling in the communication state, the communication place is limited to a specific place where the restraint device is installed, and the opportunity to perform large-capacity data communication is limited. There was a problem that the opportunity to obtain information was reduced.

  The present invention has been made in view of the above-described points, and an object of the present invention is to provide a mobile communication system capable of performing large-capacity data communication without being limited to a stop location.

The mobile communication system of the present invention includes a moving state detecting means for detecting that the vehicle is stopped or slowing down within the wireless area of the access point,
A mobile environment detection means for detecting that there is traffic on the road ahead from traffic information,
Electric field strength measuring means for measuring electric field strength of radio waves transmitted from the access point;
Receiving means for connecting to the access point and receiving data downloaded from a data server;
The vehicle moving state detection means detects that the stop or creep within the wireless area of the access point, and detects that in the mobile environment detecting means is congestion in the road ahead, and wherein the electric field when the electric field intensity of the signals transmitted by the intensity measuring means from the access point is above a predetermined value, to receive the data to be downloaded to the receiving means from the data server connected to the access point.

  According to the present invention, large-capacity data communication can be performed without being limited to a stop location.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a system configuration diagram of a first embodiment of a mobile communication system of the present invention.
In the figure, a vehicle 10 includes a wireless communication unit 11, an electric field strength measurement unit 12, a communication control unit 13, a car navigation system 14, a vehicle speed meter 15, a camera 16, a temporary stop recognition unit 17, a lane determination unit 18, content data. A management unit 19, a content data storage unit 20, and a content data selection unit 21 are provided.

  The wireless communication unit 11 receives information transmitted from the transmission unit 31 of the traffic light 30, and also has a narrow communication (large size) such as a wireless LAN having a high transmission speed with the access point (AP) 40 for road-to-vehicle communication. (Capacity data communication) and wide-area communication with a low communication speed but a wide communication area.

  The electric field strength measuring unit 12 measures the electric field strength of the radio wave transmitted from the access point 40 and supplies it to the communication control unit 13.

  The communication control unit 13 performs a download process described later.

  When the destination is input, the car navigation system 14 searches for a travel route to the destination, sets an optimal travel route as a set route, and detects an access point for road-to-vehicle communication on the set route. To the communication control unit 13. The vehicle speed meter 15 measures the vehicle speed and supplies it to the communication control unit 13.

  The camera 16 captures an area that extends in a predetermined angular range including the traveling lane ahead of the vehicle, and supplies the video signal to the temporary stop recognition unit 17 and the lane determination unit 18. The pause recognition unit 17 performs image processing on the video signal, recognizes a pause sign or a pause line, and supplies a recognition result to the communication control unit 13.

  The lane determination unit 18 performs image processing on the video signal to recognize the travel lane of the vehicle 10 and supplies the recognition result to the communication control unit 13. Note that, for example, the method described in Patent Document 1 is used for travel lane recognition. That is, if the left white line of the vehicle is a broken line and the right white line is a solid line, the vehicle is recognized as being in the right end lane.

  The content data management unit 19 stores and manages content data information and content data downloaded from the data server 70 from the access point 40 via the wireless communication unit 11 in the content data storage unit 20.

  Further, the content data management unit 19 makes a download request to the communication control unit 13 so as to download the content selected by the content data selection unit 21. The content data selection unit 21 has a display unit for selecting content, and a list of usable content data is displayed on the display unit using the content data information. The content data information includes the content name of each content data that can be used, a content outline description, the content data amount, and the like.

  The traffic signal 30 installed in the vicinity of the access point 40 has information on the current signal status (blue, yellow, or red), the period at which each signal status changes, and the average time required for a right turn at the traffic signal position. Is transmitted from the transmission unit 31.

  The access point 40 and the base station 50 are connected to the data server 70 via the network 60.

  The access point 40 is connected to the wireless communication unit 11 of the vehicle 10 via a wireless LAN, and transmits content data supplied from the data server 70 to the vehicle 10 in response to a download request from the vehicle 10. In addition, the base station 50 performs wide area communication with the wireless communication unit 11 of the vehicle 10 and transmits a list of usable content data to the vehicle 10.

  In the present invention, large capacity data communication such as content data is performed from the access point 40 to the wireless communication unit 11 of the vehicle 10 when the vehicle 10 stops in the wireless area of the access point 40 for a certain period of time.

  There are the following four methods for detecting whether or not the vehicle 10 stops for a certain period of time in the wireless area of the access point 40.

  The first method detects signal waiting from the state of a traffic light in front of the vehicle and the running / stopped state of the vehicle.

  The second method detects a signal turn waiting from the state of a traffic light in front of the vehicle and the lane where the vehicle is.

  The third method detects a stop from recognition of a stop sign or a stop line.

  The fourth method detects stop or slowing down.

<First Embodiment>
In this embodiment, a first method of detecting a signal waiting from the state of a traffic light in front of the vehicle and the running / stopped state of the vehicle is used.

  FIG. 2 shows a flowchart of the first embodiment of the download process executed by the vehicle. In the figure, the occupant of the vehicle 10 selects content data to be downloaded from the list of content data displayed on the display unit of the content data selection unit 21 in step S10.

  In step S <b> 11, the communication control unit 13 determines whether it is within the wireless area of the access point 40 from the detection information of the car navigation system 14. If within the wireless area, in step S12, the communication control unit 13 determines whether or not the vehicle 10 is stopped or in the middle of stopping based on the current speed from the vehicle speed meter 15 and the vehicle speed several seconds before.

  In the case of stopping or in the middle of stopping, in step S13, the communication control unit 13 determines whether the current signal state is yellow or red based on the information received from the traffic light 30. In the case of yellow or red, in step S14, the communication control unit 13 obtains the time from when each signal state changes until the signal state of the traffic light 30 turns blue, that is, the stop time, and downloads the content data selected for download. The download time is obtained from the content data amount and the communication speed at the access point 40, and it is determined whether or not the download can be completed within the download time.

  Note that even when content data to be downloaded is not selected, push-type distribution in which content is downloaded under the initiative of the data server 70 may be performed by setting the download time as a default value.

  If the download can be completed, the communication control unit 13 determines in step S15 whether or not the electric field strength detected by the electric field strength measuring unit 12 is equal to or greater than a certain value. In S <b> 16, the communication control unit 13 connects the wireless communication unit 11 to the access point 40, downloads the selected content data, and the downloaded content data is stored in the content data storage unit 20. Note that step S15 is not necessarily provided.

Second Embodiment
In this embodiment, the second method of detecting the signal right turn waiting from the state of the traffic signal ahead of the vehicle and the lane where the vehicle is located is used.

  FIG. 3 shows a flowchart of the second embodiment of the download process executed by the vehicle. In the figure, in step S20, the occupant of the vehicle 10 selects content data to be downloaded from the list of content data displayed on the display unit of the content data selection unit 21.

  In step S <b> 21, the communication control unit 13 determines whether it is within the wireless area of the access point 40 from the detection information of the car navigation system 14. If within the wireless area, in step S22, the communication control unit 13 determines whether or not the vehicle 10 is stopped or in the middle of stopping from the current and several seconds before the vehicle speed.

  In the case of stopping or in the middle of stopping, in step S23, the communication control unit 13 determines whether or not the current signal state is yellow or red based on the information received from the traffic light 30. If it is yellow or red, in step S24, the communication control unit 13 determines whether or not the host vehicle is in the right end lane (that is, the right turn lane at the intersection) based on the recognition information from the lane determination unit 18. Instead of the recognition information from the lane determination unit 18, it may be used whether or not the direction indicator instructs to turn right.

  When in the right turn lane (or instructing a right turn), in step S25, the communication control unit 13 determines that the average time required for a right turn at the signal position of the information received from the traffic signal 30 is the content of the content data selected for download. It is determined whether or not the download can be completed within the download time obtained from the data amount and the communication speed at the access point 40.

  Note that even when content data to be downloaded is not selected, push-type distribution in which content is downloaded under the initiative of the data server 70 may be performed by setting the download time as a default value.

  If the download is complete, the communication control unit 13 determines in step S26 whether or not the electric field strength detected by the electric field strength measuring unit 12 is equal to or greater than a certain value. In S 27, the communication control unit 13 connects the wireless communication unit 11 to the access point 40, downloads the selected content data, and the downloaded content data is stored in the content data storage unit 20. Note that step S26 is not necessarily provided.

<Third Embodiment>
In this embodiment, a third method for detecting a stop from recognition of a stop sign or a stop line is used.

  FIG. 4 shows a flowchart of a third embodiment of download processing executed by the vehicle. In the figure, the passenger of the vehicle 10 selects content data to be downloaded from the list of content data displayed on the display unit of the content data selection unit 21 in step S30.

  In step S <b> 31, the communication control unit 13 determines whether it is within the wireless area of the access point 40 from the detection information of the car navigation system 14. If it is within the wireless area, in step S32, the communication control unit 13 determines whether or not the vehicle 10 is stopped or in the middle of stopping from the current and several seconds before the vehicle speed.

  In the case of stopping or in the middle of stopping, in step S33, the communication control unit 13 determines whether or not a stop sign or a stop line has been recognized based on the recognition result from the stop recognition unit 17. If a stop sign or a stop line is recognized, the average time (fixed value) of the pause is obtained from the content data amount of the download-selected content data and the communication speed at the access point 40 in step S34. It is determined whether or not the download can be completed within the download time.

  Note that even when content data to be downloaded is not selected, push-type distribution in which content is downloaded under the initiative of the data server 70 may be performed by setting the download time as a default value.

  If the download can be completed, in step S35, the communication control unit 13 determines whether or not the electric field strength detected by the electric field strength measuring unit 12 is equal to or greater than a predetermined value. In S 36, the communication control unit 13 connects the wireless communication unit 11 to the access point 40, downloads the selected content data, and the downloaded content data is stored in the content data storage unit 20. Note that step S35 is not necessarily provided.

<Fourth embodiment>
In this embodiment, a fourth method for detecting stop or slowing is used.

  FIG. 5 shows a flowchart of a fourth embodiment of download processing executed by the vehicle. In the figure, in step S40, the occupant of the vehicle 10 selects content data to be downloaded from the list of content data displayed on the display unit of the content data selection unit 21.

  In step S <b> 41, the communication control unit 13 determines whether it is within the wireless area of the access point 40 from the detection information of the car navigation system 14. If within the wireless area, if within the wireless area at step S42, the communication control unit 13 at step S42 determines whether or not the vehicle 10 is stopped or slowed down (for example, the vehicle speed is 10 km / h or less) from the current and several seconds before the vehicle speed. Is determined.

  In the case of stopping or slowing down, in step S43, the communication control unit 13 determines whether there is traffic on the road ahead by traffic information obtained from the VICS (Road Traffic Information Communication System) via the car navigation system 14. If there is a traffic jam on the road ahead, in step S44, the communication control unit 13 determines whether or not the electric field strength detected by the electric field strength measuring unit 12 is a certain value or more, and the electric field strength is a certain value or more. If there is, the communication control unit 13 connects the wireless communication unit 11 to the access point 40 in step S45, downloads the selected content data, and the downloaded content data is stored in the content data storage unit 20. Note that step S44 is not necessarily provided.

  In this way, the vehicle 10 can perform large-capacity data communication with the access point 40 without being limited to the stop location.

  The vehicle 10 corresponds to a moving body described in the claims, the car navigation system 14 and the vehicle speedometer 15 correspond to moving state detecting means, and the camera 16, the temporary stop recognizing unit 17, and the lane determining unit 18 include moving environment detecting means. The communication control unit 13 corresponds to a stop state prediction unit, and the wireless communication unit 11, the content data management unit 19, and the content data storage unit 20 correspond to a reception unit.

1 is a system configuration diagram of a first embodiment of a mobile communication system of the present invention. It is a flowchart of 1st Embodiment of the download process which a vehicle performs. It is a flowchart of 2nd Embodiment of the download process which a vehicle performs. It is a flowchart of 3rd Embodiment of the download process which a vehicle performs. It is a flowchart of 4th Embodiment of the download process which a vehicle performs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vehicle 11 Wireless communication part 12 Electric field strength measurement part 13 Communication control part 14 Car navigation system 15 Vehicle speedometer 16 Camera 17 Pause recognition part 18 Lane determination part 19 Content data management part 20 Content data storage part 21 Content data selection part 30 Traffic light 31 Transmitter 40 Access Point 50 Base Station 60 Network 70 Data Server

Claims (1)

A moving state detecting means for detecting that the vehicle is stopped or slowing down in the wireless area of the access point;
A mobile environment detection means for detecting that there is traffic on the road ahead from traffic information,
Electric field strength measuring means for measuring electric field strength of radio waves transmitted from the access point;
Receiving means for connecting to the access point and receiving data downloaded from a data server;
The vehicle moving state detection means detects that the stop or creep within the wireless area of the access point, and detects that in the mobile environment detecting means is congestion in the road ahead, and wherein the electric field when the electric field intensity of the signals transmitted by the intensity measuring means from the access point is above a predetermined value, <br/> receiving data to be downloaded to the receiving means from the data server connected to the access point A mobile communication system.

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