JP2006262175A - In-vehicle wireless lan apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology for selecting an optimum wireless LAN access point among a plurality of wireless LAN access points existing in the perimeter of a vehicle during traveling. <P>SOLUTION: A wireless LAN apparatus first searches an RSSI of a beacon broadcast from access points (S401), generates an RSSI list of the wireless LAN access points existing in the perimeter of a present position of its own vehicle (S402), and particularizes available access points at a present point of time. Then the wireless LAN apparatus reads a perimeter access point list (S403) and filters the wireless LAN access points in the perimeter access point list by using the RSSI list (S404). Then the wireless LAN apparatus selects wireless LAN access points with profiles in the perimeter access point list having been filtered (S405) and tries network connection to the access points (S406). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle-mounted wireless LAN device, and more particularly to a vehicle-mounted wireless LAN device that can be interlocked with a car navigation device.

  In recent years, wireless LAN has been widely used as one of means for connecting to the Internet. A wireless LAN is a form of LAN that can form a network without using a cable. The standardization of the wireless LAN has been advanced with IEEE 802.11, and at present, 802.11b, which can communicate at a maximum of 11 Mbps using a 2.4 GHz band radio wave, and a maximum of 54 Mbps using a 2.4 GHz band radio wave. There are three standards: 802.11g, which allows communication of up to 54 Mbps using a 5.2 GHz band radio wave. If a wireless LAN system is constructed using network equipment compliant with these standards, anyone can easily construct a wireless LAN. For example, by connecting to a wireless base station called an access point from a notebook computer on which a wireless LAN module is mounted, it is possible to connect to the Internet without a cable connection. Recently, it is possible to connect not only to a personal wireless LAN access point installed at home but also to a public access point installed outdoors or a paid access point provided by a provider.

Furthermore, recently, various attempts have been made to download a variety of information while moving in a vehicle by mounting a wireless LAN system on the vehicle. For example, a telemarketing service has been started that provides entertainment information such as traffic information and music by wireless connection from a vehicle to an access point. Japanese Patent Laid-Open No. 2003-302232 displays a radio wave reachable range of a facility equipped with a wireless LAN access point on a screen, and informs that when a vehicle enters the range and directly communicates with the facility. And a wireless LAN system for obtaining necessary information such as tourist spot information is disclosed. In this system, a mobile phone is used to access a homepage that distributes tourist spot information via the Internet, and a list of facilities equipped with wireless LAN access points is obtained from the homepage. It moves to the spot and connects to the wireless LAN access point to obtain necessary information.
JP 2003-302232 A

  By the way, in an in-vehicle wireless LAN system, information called a profile is required to actually connect to a wireless LAN access point. That is, even if a connectable wireless LAN access point is detected as a result of the search for the wireless LAN access point, the wireless LAN access point cannot be connected without knowing its profile. A profile usually includes a MAC identifier, security information (encryption method and its encryption key), etc., in addition to an SSID (Service Set Identifier) which is a network identifier, and further for connecting to a network such as the Internet. Login information may be required.

  However, if the profile is obtained in advance via the Internet or by directly contacting the administrator of the access point, the profile must be set manually, which is complicated. There are many. Moreover, it is impossible to perform such work while driving a car. Although it is conceivable to create a profile of a wireless LAN access point in advance, the SSID of the wireless LAN access point can be freely named by the administrator, and the wireless LAN access point in one place and the wireless in another place Since the SSIDs of LAN access points may be the same, it is very difficult to find a connectable wireless LAN access point profile from an enormous number of profiles simply by preparing in advance. At the same time, there is a problem that a long time is required for the search processing.

  Accordingly, an object of the present invention is to easily realize setting of profile information necessary for connection to a wireless LAN access point and connection to the wireless LAN access point in an in-vehicle wireless LAN device that can be interlocked with a car navigation device. There is.

  The above object of the present invention is an in-vehicle wireless LAN device that can be linked to a car navigation device that can specify the current position of a vehicle, a recording unit that records the position information and profile of a wireless base station in association with each other, and a wireless base station A wireless communication module for connecting to the station, and detecting a connectable wireless base station by searching a received signal strength of a signal transmitted from the wireless base station, and at least a current position of the vehicle and the recording means On the basis of the position information recorded on the vehicle, a radio base station existing around the current position of the vehicle is extracted, and the detected radio base station is extracted from the extracted radio base stations. This is achieved by an in-vehicle wireless LAN device that selects a connection destination as a connection destination.

  In the present invention, the profile preferably includes a MAC address, an encryption method, and an encryption key, and more preferably includes a communication method and a carrier frequency.

  According to the present invention, in a vehicle-mounted wireless LAN device that can be linked to a car navigation device that can identify the current position of a vehicle, setting of profile information necessary for connection to the wireless LAN access point and connection to the wireless LAN access point are performed. Connection can be easily realized.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram showing a configuration of a wireless LAN system according to a preferred embodiment of the present invention.

  As shown in FIG. 1, the wireless LAN system 1 includes a wireless LAN access point 10 installed at an arbitrary place and an in-vehicle wireless LAN device 20 mounted on a vehicle X.

  The wireless LAN access point 10 is a network device that forms a wireless network and relays between the wireless network and the wired network. The wireless LAN access point 10 includes a wireless LAN module, and has various functions such as a router function, a firewall function, an encryption communication function, a user authentication function, and a file server function like a network device called a wireless LAN router. There are many. The wireless LAN access point 10 of the present embodiment is connected to the Internet 2, and is connected to the content provider 3, the road traffic information center 4, and the like via the Internet 2.

  On the other hand, the wireless LAN device 20 has a function of interlocking with the car navigation device. As is well known, the car navigation device is a device that specifies the current position of the vehicle X based on position information from the GPS, and further guides the route of the vehicle X to a desired destination. Although details will be described later, the car navigation device of the present embodiment has map information such as roads, buildings, stores, and landscapes. The map information is recorded in a recording means such as a DVD-ROM or a hard disk drive, and after being read and processed in the car navigation device, it is displayed on the display as a route guidance screen to the destination, and from the speaker as voice guidance. Is output.

  FIG. 2 is a diagram showing a configuration of the wireless LAN device 20 including the car navigation device.

  As shown in FIG. 2, the wireless LAN device 20 includes a system MPU 21 that performs various arithmetic processes by executing predetermined programs, and distances and distances between the vehicle and the GPS satellites that receive signals from the GPS satellites. GPS receiver 22 that measures the rate of change of the vehicle, various sensors 23 such as a gyro sensor 23a and a vehicle speed pulse sensor 23b that measure the running state of the vehicle, and a hard disk drive (HDD) 24a and DVD-ROM in which map information and the like are recorded A recording medium 24 such as a drive 24b, a display 26 connected via an image processing unit 25, a microphone 28a and a speaker 28b connected via an audio processing unit 27, a control panel 29 serving as an input interface, and the above-mentioned Wireless LAN module for connecting to the wireless LAN access point 10 0 is composed of a.

  The system MPU 21 executes a predetermined program and is used for various calculations. For example, the current position of the vehicle X is calculated based on information from the GPS receiver 22 and various sensors 23. The measurement result of the GPS receiver 22 is input to the system MPU 21 together with the measurement results of the gyro sensor 23a and the vehicle speed pulse sensor 23b. The system MPU 21 calculates these to calculate the current position and traveling direction of the vehicle. Based on the current position of the vehicle X calculated in this manner, map information around the vehicle X is read from the hard disk drive 24a or DVD-ROM 24b, and the current position of the vehicle X is displayed on the display 26 so as to be superimposed on the map information. Is done. When route guidance to the destination is being performed, a landscape is displayed on the display 26 at a corner or other point where attention should be paid, and voice guidance is output from the speaker 28b. Necessary operations such as map operation and destination setting are performed by voice input to the control panel 29 and the microphone 28a.

  In addition to the above-described map information, the wireless LAN device 20 holds, as a database, location information of the wireless LAN access point 10 and information necessary for connection to the wireless LAN access point 10 called a profile. It is recorded on the DVD-ROM 24b. These pieces of information are used when connecting to a wireless LAN access point. The location information of the wireless LAN access point 10 may be displayed on the display 26 together with the map information as necessary, or may not be displayed. Furthermore, such display / non-display may be freely switched.

  The wireless LAN device 20 may further hold information on the wireless LAN communication method and carrier frequency configuration as information necessary for connection to the wireless LAN access point 10. The regulations of the Radio Law are often different between countries or regions, but in such a case, even in the same wireless LAN communication, the communication method and frequency configuration may be different. For example, looking across countries, Japan has 13 frequency channels, the United States has 11 channels, and France has 4 channels. Therefore, communication is impossible when the vehicle moves between such areas while the vehicle is moving. In the present embodiment, it is possible to cope with such special circumstances by recording the communication method and carrier frequency configuration that are likely to be subject to legal regulations in association with the location information of the wireless LAN access point. . Examples of the communication system include a DSSS (Direct Sequence Spectrum Spread) system and an FHSS (Frequency Hopping Spectrum Spread) system.

  The wireless LAN module 30 is a communication module for wirelessly connecting to the wireless LAN access point 10. The wireless LAN module 30 is mounted in common with the wireless LAN access point 10 and the wireless LAN device 20, but there are various forms such as a PCMCIA card type, a USB stick type, a PCI board type, and an onboard type. . By connecting the wireless LAN device 20 and the wireless LAN access point 10 via the wireless LAN module 30, for example, the wireless LAN device 20 accesses the content provider 3 or the road traffic information center 4 on the Internet 2 to It is possible to download information such as information, music files, video files, and HTML documents.

  FIG. 3 is a block diagram schematically showing the configuration of the wireless LAN module 30.

  As shown in FIG. 3, the wireless LAN module 30 includes a bus interface (I / F) 31 for connection to the access point body or the wireless LAN apparatus body, and a MAC that performs access control such as packet processing and CSMA / CA. A (Media Access Control) unit 32; a BB (Base Band) unit 33 that performs primary modulation by a PSK (Phase Shift Keying) modulation method, a CCK (Complementary Code Keying) modulation method, and secondary modulation by a spread spectrum communication method; An RF unit 34 that performs RF processing of a signal, an antenna 35, a controller 36 that controls each unit, and a memory 37 that stores firmware and data such as a MAC address for executing a predetermined communication protocol are provided.

  The signal received by the antenna 35 is reproduced as an original packet processed in the order of the RF unit 34, the BB unit 33, and the MAC unit 32, and transferred to the access point main unit side or the wireless LAN device main unit side via the bus interface 31. The At the time of packet transmission, a transmission packet is input via the bus interface 31, and then processed in the order of the MAC unit 32, the BB unit 33, and the RF unit 34, and transmitted from the antenna 35 as a radio wave. In the wireless LAN device 20, when searching for a connectable access point, a beacon signal broadcast from the access point is received by the RF unit 34, and an SSID (Service Set Identifier) of the access point is acquired. The received signal strength (RSSI) is measured. The acquired SSID and received signal strength are transferred to the wireless LAN device main body side via the bus interface 31.

  The wireless LAN device 20 having the above configuration establishes a network connection with the wireless LAN access point 10 to perform communication. At this time, the wireless LAN device 20 performs wireless LAN access according to the following procedure. Connect to point 10.

  FIG. 4 is a flowchart showing a connection procedure to a wireless LAN access point.

  As shown in FIG. 4, the wireless LAN device 20 first searches for the received signal strength (RSSI) of the beacon broadcast from the access point (S401), and the wireless LAN existing around the current position of the own vehicle. An RSSI list of access points is created (S402), and currently available wireless LAN access points are specified.

  FIG. 5 is a diagram illustrating an example of the RSSI list. Information included in the detected beacon is registered in the RSSI list. In this example, “list No.”, “SSID”, and “RSSI” are shown. Note that an SSID (Service Set Identifier) is an ID used for network identification, and plays a role in logically grouping wireless LAN networks. Recently, ESSID (Extended Service Set Identifier) may be used instead of SSID.

  Next, the wireless LAN device 20 reads a list of wireless LAN access points (peripheral access point list) existing around the current position of the vehicle (S403). This peripheral access point list is created and held in advance by the wireless LAN device 20, and is regularly updated to the latest information.

  FIG. 6 is a diagram showing an example of a peripheral access point list. In this example, “No.”, “SSID”, “location information” and “profile” of the wireless LAN access point are shown. As described above, the profile is a setting file including information necessary for connection to the wireless LAN access point, and includes, for example, a MAC address, an encryption method, and an encryption key thereof. Examples of the encryption method include WEP, TKIP, and AES. Note that a profile is not associated with all wireless LAN access points registered in the database. This is because the wireless LAN access point is, for example, a paid access point and the profile cannot be known unless a contract is made. Therefore, as shown in the figure, some wireless LAN access points listed in the peripheral access point list have no profile added.

  Next, the wireless LAN access points in the peripheral access point list are filtered using the RSSI list (S404). The RSSI list is a list of wireless LAN access points that are actually operating, but the peripheral access point list is only a list on the database, and a wireless LAN access point actually exists at that position, or a wireless LAN access point list. It is unknown whether the access point is actually operating. Therefore, by superimposing the peripheral access point list and the RSSI list, only wireless LAN access points that can actually be connected are listed.

  Then, a wireless LAN access point with a profile is selected from the filtered peripheral access point list (S405), and network connection is attempted to the wireless LAN access point (S406). After the connection is established, the communication state and the distance to the access point are monitored (S407), and when the connection is difficult to maintain, the above-described series of connection procedures is resumed (S407Y, S401-S406).

  FIG. 7 is a flowchart showing a procedure for creating (updating) a peripheral access point list.

  As shown in FIG. 7, the wireless LAN device 20 first receives GPS data (S701), processes the GPS data together with the output results of various sensors, and calculates the exact position of the vehicle (S702). Next, based on the position information of the own vehicle obtained in this way, the wireless LAN device 20 uses the wireless LAN around the current position of the own vehicle from a database in which information of all wireless LAN access points is recorded. By listing the access points (S703), the peripheral access point list shown in FIG. 7 is created (S704). By periodically repeating the above steps, the peripheral access point list is updated and the latest state is maintained. By referring to this peripheral access point when selecting a wireless LAN access point, a connectable wireless LAN access point can be quickly selected.

  As described above, according to the present embodiment, a database in which wireless LAN access point location information and profiles are associated one-to-one is prepared, and the profile is specified based on the location information of the wireless LAN access point. Therefore, the profile of a desired access point can be searched quickly and reliably from a large number of wireless LAN access points that can have the same SSID. Furthermore, the use of such a database can save the trouble of manually setting the profile.

  The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention, and these are also included in the scope of the present invention. Needless to say.

  For example, in the above embodiment, a wireless LAN device including a car navigation device has been described. However, the present invention is not limited to this, and for example, an in-vehicle computer mounted with a wireless LAN module is a car navigation device. It is also possible to prepare the present invention separately and realize the present invention by linking the in-vehicle computer and the car navigation device. The wireless LAN device of the above embodiment can also be viewed as an in-vehicle computer having both a wireless LAN function and a wireless LAN function, or a car navigation device having a wireless LAN function. That is, the present invention can take various forms as long as the wireless LAN function and the car navigation function are linked.

  Further, in the above embodiment, as shown in FIG. 6, after creating a peripheral access point list in which a wireless LAN access point with a profile and a wireless LAN access point with an unknown profile are listed together The wireless LAN access points that can be connected are listed up by filtering using the RSSI list, and a wireless LAN access point having a profile is selected as a connection destination from the list. The access point is not limited to this, and only the access points to which the profile is attached may be extracted in advance when the peripheral access point list is created. In this way, it is not necessary to narrow down the wireless LAN access points by the profile in a later step.

  In the above embodiment, the wireless LAN access point database in which the position information and profile of the wireless LAN access point are associated is recorded on a recording medium such as a DVD-ROM or HDD together with map information for car navigation. Although described, these may be recorded separately on different recording media. If a recording medium in which a wireless LAN access point database is recorded is prepared separately, a database can be constructed using a DVD-ROM or the like in which only general car navigation map information is recorded as it is. In addition, when a rewritable (addable) recording medium such as an HDD is used, the profile of the wireless LAN access point can be easily changed. Anyone can freely install a wireless LAN access point, and the administrator can freely change profile settings etc. at any time. By using a rewritable recording medium, a database can be created according to the installation status of the wireless LAN access point. Can be updated quickly.

FIG. 1 is a diagram showing a configuration of a wireless network system according to a preferred embodiment of the present invention. FIG. 2 is a diagram illustrating a configuration of the wireless LAN device 20. FIG. 3 is a block diagram schematically showing the configuration of the wireless LAN module 30. FIG. 4 is a flowchart showing a connection procedure to a wireless LAN access point. FIG. 5 is a diagram illustrating an example of the RSSI list. FIG. 6 is a diagram illustrating an example of a peripheral access point list. FIG. 7 is a flowchart showing a procedure for creating (updating) a peripheral access point list.

Explanation of symbols

1 Wireless LAN System 2 Internet 3 Content Provider 4 Road Traffic Information Center 10 Wireless LAN Access Point 20 Wireless LAN Device 21 System MPU
22 GPS receiver 23 Various sensors 23a Gyro sensor 23b Vehicle speed pulse sensor 24 Recording medium 24a Hard disk drive 24b DVD-ROM
25 Image processing unit 26 Display 27 Audio processing unit 28a Microphone 28b Speaker 29 Control panel 30 Wireless LAN module 31 Bus interface 32 MAC unit 33 BB unit 34 RF unit 35 Antenna 36 Controller 37 Memory X Vehicle

Claims (3)

An in-vehicle wireless LAN device that can be linked to a car navigation device that can identify the current position of a vehicle,
Recording means for associating and recording the position information and profile of the radio base station;
A wireless communication module for connecting to a wireless base station is provided,
While detecting a connectable radio base station by searching the received signal strength of the signal transmitted from the radio base station, based on at least the current position of the vehicle and the position information recorded in the recording means, Extracting a radio base station existing around the current position of the vehicle, and selecting, from the detected radio base stations, the extracted radio base station having the profile as a connection destination An in-vehicle wireless LAN device characterized by the above.   The in-vehicle wireless LAN device according to claim 1, wherein the profile includes a MAC address, an encryption method, and an encryption key. The in-vehicle wireless LAN device according to claim 2, wherein the profile includes a communication method and a carrier frequency.

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