JP2009126412A - Communication control method of instrument with wireless lan - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control method for restraining wireless traffic in a vehicle by controlling a vehicle-mounted instrument with a wireless LAN to transmit required data when needed. <P>SOLUTION: This instrument includes a vehicle-mounted camera 200 with a wireless LAN installed in a vehicle, and a monitor 100 with a wireless LAN installed in the vehicle for displaying image data photographed by the vehicle-mounted camera 200. When it is determined that the vehicle is put in a back gear mode, the vehicle-mounted camera 200 and the monitor 100 display the image data photographed by the vehicle-mounted camera 200 to the monitor 100 when it is determined that the vehicle is put in the back gear mode, and brings the vehicle-mounted camera 200 into a sleep state when it is determined that the vehicle is not put in the back gear mode. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a communication control method for an in-vehicle device provided with a wireless LAN.

As a typical example of communication in the car, a front monitor installed in the vicinity of the front seat (which may be a monitor provided in a car navigation system or a music playback system) and an in-vehicle camera installed in the rear part of the vehicle. There is communication. In the current car navigation system, the car navigation system main unit and the in-vehicle camera are connected by wire, and the image data captured by the in-vehicle camera is sent to the car navigation system sequentially and displayed on the monitor of the car navigation system when necessary. Yes. For example, the image data captured by the in-vehicle camera is displayed on the monitor only during the back operation of the vehicle.
Panasonic HDD Car Navigation Station CN-HDS635RD Instruction Manual P21, P151

  However, in recent years, with the development of wireless communication technologies such as wireless LAN (Local Area Network), it has been proposed to use a wireless LAN for in-vehicle communication.

  In this case, the car navigation system has a wireless LAN communication function, and the in-vehicle camera also has a wireless LAN function. In addition, entertainment in the vehicle is also progressing, and various other in-vehicle devices such as a DVD playback device and a rear monitor provided in the vicinity of the rear seat have been equipped with a wireless LAN function. In this case, when wireless communication is performed between the respective devices, there is a problem that wireless traffic in the vehicle increases and necessary data cannot be communicated.

  In order to solve this problem, the present invention provides a control method for suppressing wireless traffic in a vehicle by controlling an in-vehicle device having a wireless LAN function to transmit necessary data when necessary.

  The present invention relates to a communication system comprising an in-vehicle camera equipped with a wireless LAN installed in a vehicle and a monitor equipped with a wireless LAN installed in the vehicle for displaying image data captured by the in-vehicle camera. When the vehicle camera and the monitor determine that the vehicle is in the back gear based on a signal indicating the vehicle is in the back gear, the monitor captures image data captured by the vehicle camera. And when the vehicle is determined not to be in the back gear, the in-vehicle camera is put into a sleep state.

  According to the present invention, it is possible to suppress radio traffic in the vehicle and to transmit necessary data when necessary.

  Furthermore, the power consumption of the in-vehicle device can be reduced because the in-vehicle device having the wireless LAN function can be appropriately controlled to the sleep state.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Embodiment 1]
1 is a system configuration diagram of an in-vehicle device that communicates by wireless LAN in a vehicle according to Embodiment 1 of the present invention.

  (1) of FIG. 1 is an example of a system configuration of an in-vehicle device, and a front monitor 100 provided with a wireless LAN installed in the vicinity of the front seat, and a wireless installed at the rear of the vehicle that performs wireless communication with the front monitor 100. It is comprised by the vehicle-mounted camera 200 provided with LAN.

  The configuration of the front monitor 100 will be described with reference to FIG. The front monitor 100 includes a W-LAN control unit 110 that communicates with other in-vehicle devices using a known wireless LAN method (for example, IEEE802.11a / b / g / n), and a W-LAN control unit 110. The image processing unit 120 stores image data received from other in-vehicle devices via an image memory (not shown), performs image processing suitable for the received image data, and displays the image data on the display unit 130 configured by an LCD or a touch panel. And a central processing unit 140 composed of a CPU and MPU that comprehensively control the functions in the front monitor 100, and a memory 150 that stores various programs and table information. The front monitor 100 may be a car navigation monitor installed in the vehicle. In this case, a reverse signal (a signal generated when the vehicle enters the back gear) is supplied from the vehicle. Further, even in the case of car navigation, there is also a portable car navigation system that can be carried freely, and may be a portable car navigation monitor (hereinafter referred to as PND), in which case no reverse signal is supplied from the vehicle.

  Next, the configuration of the in-vehicle camera 200 will be described with reference to FIG. The in-vehicle camera 200 includes an imaging unit 230 configured by a CCD or C-MOS, and an image processing unit 220 that stores image data captured by the imaging unit 230 in an image memory (not shown) and performs image processing suitable for the present system. And a W-LAN control unit that communicates image data from the image processing unit 220 with other in-vehicle devices using a known wireless LAN method (for example, IEEE802.11a / b / g / n) via an antenna. 110, a central processing unit 240 constituted by a CPU and MPU for comprehensively controlling functions in the in-vehicle camera 200, and a memory 250 in which various programs and table information are stored. Image data from the in-vehicle camera 200 is transmitted to the front monitor 100 (or 300 described later). The in-vehicle camera 200 may be supplied with a reverse signal from the vehicle.

  Next, (2) of FIG. 1 is another example of the system configuration of the in-vehicle device, and is a front monitor 300 with a DVD function (hereinafter referred to as Din) having a wireless LAN installed in the vicinity of the front seat. The vehicle-mounted camera 200 that performs wireless communication with the Din 300 and the rear monitor 400 that includes a wireless LAN installed in the vicinity of the rear seat that performs wireless communication with the Din 300 are configured.

  The configuration of the DVD function-equipped front monitor (Din) 300 will be described with reference to FIG. The Din 300 has substantially the same configuration as the front monitor 100 described above, and includes a W-LAN control unit 110, an image processing unit 120, a display unit 120, a central processing unit 140, and a memory 150. Furthermore, a DVD playback unit 360 for playing back DVD data recorded on a DVD-ROM or another recording medium is provided, and the playback data of the DVD is transmitted to the rear monitor 400 via the central control unit 140 and the W-LAN control unit 110. . The Din 300 may be a car navigation monitor with a DVD function installed in the vehicle, and in this case, a reverse signal (a signal generated when the vehicle enters the back gear) is supplied from the vehicle.

  Next, the configuration of the rear monitor 400 will be described with reference to FIG. The rear monitor 400 includes a W-LAN control unit 410 that communicates with other in-vehicle devices using a known wireless LAN method (for example, IEEE802.11a / b / g / n), and the W-LAN control unit 410. An image processing unit 420 that stores image data received from other in-vehicle devices in an image memory (not shown), performs image processing suitable for the received image data, and displays the image data on a display unit 430 constituted by an LCD, and a rear monitor The central processing unit 440 is configured by a CPU and MPU that collectively control the functions in the memory 400 and a memory 450 that stores various programs and table information. The rear monitor 400 is not supplied with a reverse signal from the vehicle.

  Next, (3) in FIG. 1 is another example of the system configuration of the in-vehicle device, and is configured by a normal DVD player 500 having a wireless LAN and the rear monitor 400 described above.

  The configuration of a normal DVD player 500 equipped with a wireless LAN will be described with reference to FIG. The normal DVD player 500 includes a W-LAN control unit 510 that communicates with other in-vehicle devices using a known wireless LAN method (for example, IEEE802.11a / b / g / n), A central processing unit 540 configured by a CPU and MPU for overall control of functions, and a DVD playback unit 560 for playing back DVD data recorded on a DVD-ROM or another recording medium. DVD reproduction data is transmitted to the rear monitor 400 via the W-LAN control unit 510.

  In such a configuration, by performing wireless communication between each in-vehicle device, the necessary data is transmitted when an in-vehicle device having a wireless LAN function is necessary so that wireless traffic in the vehicle does not increase. Thus, control is performed so that the in-vehicle device is put to sleep. As a result, radio traffic in the vehicle can be suppressed, and necessary data can be transmitted when necessary. Furthermore, the power consumption of the in-vehicle device can be reduced because the in-vehicle device having the wireless LAN function can be appropriately controlled to the sleep state.

  The sleep control will be described with reference to FIG.

  (1) of FIG. 7 shows a mode table of the in-vehicle camera 200. When the power “start when the engine is ON” reverse signal “valid”, the mode 1 and the power “start when the engine is ON” reverse signal “use” “No” is mode 2, power “starts when a reverse signal comes” reverse signal “valid” is mode 3, power “starts when reverse signal comes” reverse signal “valid” is mode 4 It shows that it becomes.

  (2) of FIG. 7 shows a control table of the front monitor 100 and the front monitor 300 with a DVD function. In the case of Din, the reverse signal is “valid”, and in the case of PND, the reverse signal is “not used”. Show.

  (3) of FIG. 7 shows a control table of the DVD function front monitor 300 and the normal DVD player 500 for DVD playback. In the case of Din, the reverse signal “valid”, and in the case of a normal DVD player, the reverse signal “ "Do not use".

  (4) in FIG. 7 shows a control table of the rear monitor 400, and the rear monitor indicates that the reverse signal is “not used”.

  (5) in FIG. 7 shows a sleep mode determined based on the control tables in FIGS. 7 (1) to (4). In the case of Din, “in-vehicle camera mode 1 has“ sleep mode 1 or 2 ”, in-vehicle The camera mode 2 is set to “sleep mode 2”, the vehicle camera mode 3 is “not used”, the vehicle camera mode 4 is “not used”, and the rear monitor is set to “sleep mode 2”. That is, when the front monitor is Din (front monitor with a DVD function), when the in-vehicle camera 200 is set to the power “start when the engine is on” in the in-vehicle mode 1 and the reverse signal “enabled”, the “sleep mode” 1 or 2 ”indicates that the vehicle-mounted camera is operated.

  Subsequently, in the case of PND, “Sleep mode 1 or 3” in in-vehicle camera mode 1, “Sleep mode 3” in in-vehicle camera mode 2, “Not used” in in-vehicle camera mode 3, “Not used” in in-vehicle camera mode 4, rear monitor Is set to “sleep mode 3”.

  Subsequently, in the case of a normal DVD player, the rear monitor is set to “sleep mode 3”.

  Next, the sleep mode process will be described with reference to the flowcharts of FIGS.

  First, the process of the sleep mode 1 will be described based on the flowchart of FIG.

  If the engine is turned on in S810, the process proceeds to S820. In S820, the vehicle camera 200 and the DVD function front monitor 300 (Din) or the portable front monitor 100 (PND) are turned on, and S830 is entered. Proceed to In S830, the in-vehicle camera 200 is set to the sleep state, and the process proceeds to S840. The sleep state of the in-vehicle camera 200 is a state in which only the W-LAN control unit 210 and the central control unit 240 of the in-vehicle camera 200 are operated and other functions are stopped. In S840, the in-vehicle camera 200 determines whether or not a reverse signal is supplied from the vehicle. If no reverse signal is received, the determination is made again in S840. If a reverse signal is received, the operation of the in-vehicle camera is performed in S850. The application is started and transmitted to the front monitor via the W-LAN control unit 210. In S860, the in-vehicle camera 200 determines whether or not the supply of the reverse signal from the vehicle is stopped. If the reverse signal is received, the determination is made again in S860, and if the supply of the reverse signal is stopped, S830 is performed. Then, the in-vehicle camera 200 enters a sleep state. That is, in the state where the vehicle to which the reverse signal is supplied is in the back gear, the in-vehicle camera 200 that has been in the sleep state is activated, and the captured image data is transmitted to the front monitor, and is transmitted to the front monitor. When the image data captured by the in-vehicle camera is displayed and the back gear is disengaged, the in-vehicle camera 200 enters a sleep state.

  Thereby, since the image of the in-vehicle camera is transmitted wirelessly only when the image of the in-vehicle camera is necessary, wireless traffic in the vehicle can be suppressed, and furthermore, the in-vehicle camera can be appropriately put into the sleep state. In addition, the power consumption of the in-vehicle camera can be suppressed.

Next, the processing in the sleep mode 2 will be described based on the flowchart of FIG.
First, control between the front monitor 300 (Din) with a DVD function and the in-vehicle camera 200 will be described. If the engine is turned on in S910, the process proceeds to S920. In S920, the power of the in-vehicle camera 200 and the front monitor 300 with a DVD function (Din) is turned on, and the process proceeds to S930. In S930, the in-vehicle camera 200 is set in the sleep state, and the process proceeds to S940. The sleep state of the in-vehicle camera 200 is a state in which only the W-LAN control unit 210 and the central control unit 240 of the in-vehicle camera 200 are operated and other functions are stopped. In S940, the Din 300 determines whether or not a reverse signal is supplied from the vehicle. If no reverse signal is received, the determination is made again in S940. If a reverse signal is received, the in-vehicle camera 200 is checked in S950. Then, a command indicating camera activation determined in advance is transmitted via wireless via the W-LAN control unit 110. In S960, the in-vehicle camera 200 receives a command indicating camera activation via wireless via the W-LAN control unit 210, starts an operation application of the in-vehicle camera, and transmits it to the Din 300 via the W-LAN control unit 210. To do. In S970, the Din 300 determines whether or not the supply of the reverse signal from the vehicle is stopped. If the reverse signal is received, the determination is made again in S970. If the supply of the reverse signal is stopped, the process proceeds to S980. Then, a command indicating a predetermined camera stop is transmitted to the in-vehicle camera 200 via the W-LAN control unit 110 via wireless. When the in-vehicle camera 200 receives a command indicating the camera stop via wireless via the W-LAN control unit 210, the in-vehicle camera 200 proceeds to S930 and sets the in-vehicle camera 200 to a sleep state. That is, when the vehicle to which the reverse signal is supplied is in the back gear, the in-vehicle camera 200 that has been in the sleep state via the Din 300 is activated, and the captured image data is transmitted to the front monitor. When the image data captured by the in-vehicle camera is displayed on the front monitor and the back gear is disengaged, the in-vehicle camera 200 is set in the sleep state from the Din 300 via the radio.

  Control between the front monitor 300 (Din) with a DVD function in the sleep mode 2 and the rear monitor 400 will be described.

If the engine is turned on in S915, the process proceeds to S925. In S925, the front monitor 300 (Din) with DVD function and the rear monitor 400 are turned on, and the process proceeds to S935. In S935, the DVD playback is activated and the DVD playback video is transmitted to the rear monitor 400 via the W-LAN control unit 210 via wireless communication. In S945, the Din 300 determines whether or not a reverse signal is supplied from the vehicle. If no reverse signal is received, it is determined again in S945. If a reverse signal is received, the rear monitor 400 is checked in S955. Then, a command indicating that the predetermined rear monitor is set to the sleep state is transmitted via the W-LAN control unit 210 via the radio. The sleep state of the rear monitor 400 refers to a state in which only the W-LAN control unit 410 and the central control unit 440 of the rear monitor 400 are operated and other functions are stopped. In S965, the rear camera 400 receives a command indicating that the rear monitor via wireless is set to the sleep state via the W-LAN control unit 410 and causes the rear camera 400 to execute sleep. In S975, the Din 300 determines whether or not the supply of the reverse signal from the vehicle is stopped. If the reverse signal is received, the determination is made again in S975. If the supply of the reverse signal is stopped, the process proceeds to S985. Then, a command indicating activation of a predetermined rear monitor is transmitted to the rear monitor 400 via the W-LAN control unit 210 via radio. When the rear monitor 400 receives a command indicating activation of the rear monitor via wireless via the W-LAN control unit 410, the rear monitor 400 proceeds to S <b> 935, activates DVD reproduction, and transmits the DVD reproduction video via the W-LAN control unit 210 via wireless. To the rear monitor 400.
In other words, in the sleep mode 2, before the vehicle to which the reverse signal is supplied enters the back gear, the in-vehicle camera is in the sleep state, and the Din DVD image is transmitted to the back monitor via the wireless communication. In the state where the DVD video is played back and the vehicle is in the back gear, the in-vehicle camera 200 that has been in the sleep state via the Din 300 is activated, and at the same time, the rear monitor is in the sleep state, and the captured image data Is transmitted to the front monitor, and when the image data captured by the in-vehicle camera is displayed on the front monitor and the back gear is released, the in-vehicle camera 200 is set in the sleep state via the radio from the Din 300, and the rear monitor is activated.

  As a result, since the in-vehicle camera image is transmitted wirelessly only when the in-vehicle camera image is necessary, the DVD video is also transmitted to the rear monitor only when necessary, so that the radio traffic in the vehicle can be suppressed. In addition, since the in-vehicle camera and the rear monitor can be appropriately put into a sleep state, the power consumption of the in-vehicle camera and the rear monitor can be suppressed.

Next, the processing in the sleep mode 3 will be described based on the flowchart of FIG.
First, control between the portable type front monitor 100 (PND) and the in-vehicle camera 200 will be described. In S1010, if the engine is turned on and the PND 100 is powered on, the process proceeds to S1020. In S1020, the power of the in-vehicle camera 200 and the portable type front monitor 100 (PND) is turned on, and the process proceeds to S1030. In S1030, the in-vehicle camera 200 is set in the sleep state, and the process proceeds to S1040. The sleep state of the in-vehicle camera 200 is a state in which only the W-LAN control unit 210 and the central control unit 240 of the in-vehicle camera 200 are operated and other functions are stopped. In S1040, the user of PND 100 desires an image of in-vehicle camera 200 and determines whether or not a button or a touch panel (not shown) for activating in-vehicle camera 200 has been pressed. If not, in S1040 again. If determined and pressed, in S1050, a command indicating camera activation determined in advance is transmitted to the in-vehicle camera 200 via the W-LAN control unit 110 via radio. In S1060, the in-vehicle camera 200 receives a command indicating camera activation via wireless via the W-LAN control unit 210, starts an operation application of the in-vehicle camera, and transmits it to the PND 100 via the W-LAN control unit 210. To do. In S1070, the user of PND 100 determines whether or not the image of in-vehicle camera 200 is unnecessary and presses a button or a touch panel (not shown) for causing in-vehicle camera 200 to sleep. If it is determined and pressed, the process proceeds to S1080, and a command indicating a predetermined camera stop is transmitted to the in-vehicle camera 200 via the W-LAN control unit 110 via radio. When the in-vehicle camera 200 receives a command indicating the camera stop via wireless via the W-LAN control unit 210, the in-vehicle camera 200 proceeds to S1030 and sets the in-vehicle camera 200 to a sleep state. That is, when the user wants to activate the in-vehicle camera, the user presses a predetermined button of the PND 100 to activate the in-vehicle camera 200 that has been in the sleep state from the PND 100 via radio, and the captured image data is displayed on the front monitor. When the user wants to stop the in-vehicle camera when the image data captured by the in-vehicle camera is displayed on the front monitor and the user wants to stop the in-vehicle camera, the user presses a predetermined button on the PND 100 to activate the PND 100 via the wireless connection. The in-vehicle camera 200 that has been put into a sleep state.

  The control between the portable type front monitor 100 (PND) / normal DVD player 500 and the rear monitor 400 in the sleep mode 3 will be described.

  If the engine is turned on and the power of the PND 100 / normal DVD player 500 is turned on in S1015, the process proceeds to S1025. In S1025, the PND 100 / normal DVD player 500 and the rear monitor 400 are turned on, and the process proceeds to S1035. In S 1035, only in the case of the normal DVD player 500, DVD playback is activated and the DVD playback video is transmitted to the rear monitor 400 via the W-LAN control unit 510 via wireless communication. In step S1045, the user of the PND 100 / normal DVD player 500 desires an image of the in-vehicle camera 200, determines whether or not a button or a touch panel (not shown) for starting the in-vehicle camera 200 is pressed, and the user must press the button. For example, if it is determined again in S1045 and pressed, in S1055, a command indicating predetermined camera activation is transmitted to the vehicle-mounted camera 200 via the W-LAN control units 110 and 510 via wireless. . In S <b> 1065, the in-vehicle camera 200 receives a command indicating camera activation via wireless via the W-LAN control unit 210, starts an operation application of the in-vehicle camera, and starts the PND 100 / normal via the W-LAN control unit 210. The data is transmitted to the DVD player 500. In S1075, the user of the PND 100 / normal DVD player 500 determines whether or not the image of the in-vehicle camera 200 is unnecessary and presses a button or a touch panel (not shown) for causing the in-vehicle camera 200 to sleep. If it is determined again in step S1075 and pressed, the process proceeds to step S1085, and a command indicating a predetermined camera stop is transmitted to the in-vehicle camera 200 via the W-LAN control units 110 and 510 via radio. . When the in-vehicle camera 200 receives a command indicating the camera stop via wireless via the W-LAN control unit 210, the in-vehicle camera 200 proceeds to S1035 and sets the in-vehicle camera 200 to a sleep state. That is, when the user wants to activate the in-vehicle camera, the user presses a predetermined button of the PND 100 to activate the in-vehicle camera 200 that has been in the sleep state from the PND 100 via radio, and the captured image data is displayed on the front monitor. When the user wants to stop the in-vehicle camera when the image data captured by the in-vehicle camera is displayed on the front monitor and the user wants to stop the in-vehicle camera, the user presses a predetermined button on the PND 100 to activate the PND 100 via the wireless connection. The in-vehicle camera 200 that has been put into a sleep state.

  As a result, since the in-vehicle camera image is transmitted wirelessly only when the in-vehicle camera image is necessary, the DVD video is also transmitted to the rear monitor only when necessary, so that the radio traffic in the vehicle can be suppressed. In addition, since the in-vehicle camera and the rear monitor can be appropriately put into a sleep state, the power consumption of the in-vehicle camera and the rear monitor can be suppressed.

  As another embodiment, the in-vehicle camera puts the in-vehicle camera into a sleep state when the beacon of the other party (for example, PND) that tries to transmit image data acquired by wireless connection cannot be obtained. Anyway.

1 is a system configuration diagram of an in-vehicle device that communicates with a wireless LAN in a vehicle according to a first embodiment of the present invention. It is a functional block diagram of the front monitor of the first embodiment. It is a functional block diagram of the vehicle-mounted camera of the first embodiment. It is a functional block diagram of a front monitor (Din) with a DVD function according to the first embodiment. It is a functional block diagram of the rear monitor of the first embodiment. 3 is a functional block diagram of a normal DVD player provided with a wireless LAN according to the first embodiment. FIG. It is a schematic diagram which shows the table regarding the sleep control of this Embodiment 1. FIG. 3 is a flowchart illustrating control processing in sleep mode 1 according to the first embodiment. 6 is a flowchart illustrating control processing in sleep mode 2 according to the first embodiment. 6 is a flowchart illustrating control processing in sleep mode 3 according to the first embodiment.

Explanation of symbols

100 Front monitor 200 In-vehicle camera 300 Front monitor with DVD function (Din)
400 Rear monitor 500 Normal DVD player 110, 210, 410, 510 W-LAN control unit 120, 220, 420 Image processing unit 130, 430 Display unit 140, 240, 440, 540 Central control unit 230 Imaging unit 360, 560 DVD playback unit

Claims (1)

In a communication system comprising an in-vehicle camera equipped with a wireless LAN installed in a vehicle, and a monitor equipped with a wireless LAN installed in the vehicle that displays image data captured by the in-vehicle camera,
The in-vehicle camera and the monitor display image data captured by the in-vehicle camera on the monitor when it is determined that the vehicle is in the back gear based on a signal indicating the state in which the vehicle is in the back gear. Then, when it is determined that the vehicle is not in the back gear, the vehicle-mounted camera is set in a sleep state.

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