JP2007006089A - Wireless communication terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication terminal capable of performing a handover led by a radio communication terminal.
[Solution]
The wireless communication terminal 10 is a wireless communication terminal that performs Bluetooth communication, and is different from the radio wave state monitoring unit 20 that monitors the radio wave state from the access point (AP) that is in communication connection and the AP that is in communication connection. A status inquiry unit 22 that acquires the status of a plurality of APs, a status list storage unit 24 that stores the status of each AP acquired by the status inquiry unit 22, and a radio wave condition monitoring unit 20 that is currently monitoring An AP determination unit 26 that determines a switching destination AP based on the status of each AP stored in the status list storage unit 24 when the radio wave state deteriorates below a predetermined threshold, and the AP determination unit 26 And a communication control unit 28 that switches connection to the determined AP.
[Selection] Figure 1

Description

  The present invention relates to a line switching method for a wireless communication terminal having a Bluetooth communication function.

  Conventionally, Bluetooth is known as a short-range wireless data communication means. Bluetooth is originally intended for communication in a narrow range such as between office devices or around a user, and is a communication means on the assumption that the devices are in a semi-stationary state. When a device moves across wireless zones, communication is cut off at the boundary of the zone, which is not suitable for continuous communication while moving.

  As a method for solving such a problem, Patent Document 1 discloses a technique that enables handover between a plurality of radio access agents. The information providing system described in Patent Literature 1 includes an information center, a plurality of wireless access agents, and a mobile device. A method for switching between wireless access agents with this configuration will be described.

Initially, the mobile device communicates with the information center through one wireless access agent. In this state, when another wireless access agent detects the mobile device, the other wireless access agent sets a connection with the mobile device. The mobile station monitors the reception levels from the two radio access agents, and when detecting that the reception level of the destination radio access agent has exceeded, the mobile station transmits a handover request signal to the information center. When receiving the handover request response from the information center, the mobile device switches to the connection with the destination wireless access agent.
JP 2003-163955 A

  However, the information providing system described in Patent Document 1 has the following problems. In other words, since the mobile station employs a scheme in which a handover request signal is transmitted to the information center via the radio access agent and a handover request response is received, the handover request signal, hand There is a possibility that the over request response may be broken, and handover may not be possible.

  Further, since the information center is a system for managing handover, when the number of mobile devices increases, the processing load on the information center increases, which may affect the original function of the information center.

  In view of the above background, an object of the present invention is to provide a wireless communication terminal capable of performing handover without using an information center.

  A wireless communication terminal according to the present invention is a wireless communication terminal that performs communication using Bluetooth, and is different from a radio wave state monitoring unit that monitors a radio wave state from an access point during communication connection and the access point during communication connection. Status inquiry means for acquiring the status of a plurality of access points, status storage means for storing the status of each access point acquired by the status inquiry means, and radio waves being monitored by the radio wave condition monitoring means The access point determination means for determining the access point to be switched based on the status of each access point stored in the status storage means when the state is deteriorated below a predetermined threshold, and the access point determination means The connection switcher that switches the connection to the access point determined And it has a configuration in which the and.

  With this configuration, the statuses of a plurality of access points other than the access points that are in communication connection are stored in the status storage means, so that the statuses of the plurality of access points that are not in communication connection can be grasped. When the state of the radio wave from the access point during communication connection deteriorates below a predetermined threshold, the access point to be switched is determined based on the status information stored in the status storage means, so communication connection to the appropriate access point Can be switched. In addition, switching control can be performed by the wireless communication terminal by using a configuration in which the wireless communication terminal determines the switching destination based on the status of the access point. Thereby, the switching process can be performed regardless of the communication state from the access point, and the burden of the switching process can be distributed to each wireless communication terminal.

  In the wireless communication terminal of the present invention, the status inquiry means has a configuration for making an inquiry about statuses to the plurality of access points as needed.

  With this configuration, information on a plurality of access points stored in the status storage unit can be updated as needed.

  A wireless communication terminal according to another aspect of the present invention is a wireless communication terminal that performs communication using Bluetooth. Based on the status of each access point stored in the status storage means, and status storage means for storing the status of each access point acquired by the status inquiry means An access point determining unit that determines a point; and a communication unit that performs communication via the access point determined by the access point determining unit.

  With this configuration, communication connections with a plurality of access points are established, and the status of each access point is stored in the status storage means, so that the status of the plurality of access points can be grasped. Since the access point via communication is determined based on the status information stored in the status storage means, communication can be performed via an appropriate access point, and the time required for switching the access point can be shortened. In addition, with the configuration in which the wireless communication terminal determines the communication destination based on the status of the access point, the switching control can be led by the wireless communication terminal. Thereby, the switching process can be performed regardless of the communication state from the access point, and the burden of the switching process can be distributed to each wireless communication terminal.

  In the wireless communication terminal of the present invention, the status inquiry means has a configuration for making an inquiry about statuses to the plurality of access points as needed.

  With this configuration, information on a plurality of access points stored in the status storage unit can be updated as needed.

  The wireless communication terminal of the present invention is configured to divide a plurality of access points connected by the plurality of connection means into an access point connected in an active mode and an access point connected in a low power consumption mode according to a status. Have.

  With this configuration, the load of connection between the wireless communication terminal and the access point can be reduced.

  A wireless communication terminal according to another aspect of the present invention is a wireless communication terminal that performs communication using Bluetooth, an access point information storage unit that stores information obtained by grouping a plurality of access points, and an access point that is in communication connection Radio wave state monitoring means for monitoring the state of radio waves from, status inquiry means for acquiring the status of a plurality of access points different from the access point being connected, and each of the status inquiry means acquired by the status inquiry means An access point belonging to the same group as the currently connected access point when the state of the radio wave being monitored by the radio wave state monitoring unit deteriorates below a predetermined threshold value. Read from the access point information storage means, read access An access point determination means for determining a switching destination access point based on the status of each access point stored in the status storage means, and an access point determined by the access point determination means. A connection switching means for switching the connection.

  With this configuration, a switching destination access point can be determined from access points grouped in advance. By grouping access points that can be switched, an access point that is not likely to be determined as a switching destination can be configured not to acquire a status, and the status acquisition process can be reduced. In addition, switching control can be performed by the wireless communication terminal by using a configuration in which the wireless communication terminal determines the switching destination based on the status of the access point. Thereby, the switching process can be performed regardless of the communication state from the access point, and the burden of the switching process can be distributed to each wireless communication terminal.

  A wireless communication terminal according to another aspect of the present invention is a wireless communication terminal that performs communication by Bluetooth, each of which is acquired by a status inquiry unit that acquires statuses of a plurality of access points, and the status inquiry unit. A status storage means for storing the status of each access point, and an access point determination means for determining an access point for communication connection based on the status of each access point stored in the status storage means .

  With this configuration, the statuses of a plurality of access points are stored in the status storage means, so that the statuses of the plurality of access points can be grasped. Since the access point of the communication connection destination is determined based on the status information stored in the status storage means, communication connection can be established with an appropriate access point.

  According to the present invention, since the wireless communication terminal determines the access point switching destination based on the statuses of a plurality of access points, there is an excellent effect that switching control can be performed led by the wireless communication terminal.

  Hereinafter, wireless communication terminals according to embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram showing a configuration of a wireless communication terminal 10 according to the first embodiment. The wireless communication terminal 10 is a terminal having a function of performing communication by Bluetooth. Prior to the description of the wireless communication terminal 10 of the present embodiment, the wireless communication system 1 to which the wireless communication terminal 10 is applied will be described.

  FIG. 2 is a diagram illustrating a configuration of the wireless communication system 1 to which the wireless communication terminal 10 is applied. The wireless communication system 1 includes a communication partner terminal 14 that is a communication partner of the wireless communication terminal 10 and a Bluetooth access point (hereinafter referred to as “AP”) 12 a to 12 that relays communication between the wireless communication terminal 10 and the communication partner terminal 14. 12g. In this specification, AP12a-12g is named generically and AP12.

  The wireless communication terminal 10 can communicate with the APs 12a to 12d within the Bluetooth communication range. FIG. 2 illustrates an example in which the wireless communication terminal 10 communicates with the APs 12a to 12d. In the present embodiment, the wireless communication terminal 10 is communicably connected to the AP 12c, and acquires the radio wave state and various information that are part of the status of the APs 12a, 12b, and 12c.

  Returning to FIG. 1, the configuration of the wireless communication terminal 10 will be described. As shown in FIG. 1, the wireless communication terminal 10 includes a radio wave state monitoring unit 20 that monitors a radio wave state from a connected AP 12c, and a status inquiry unit 22 that monitors the statuses of other APs 12a, 12b, and 12d. A status list storage unit 24 that stores status information acquired by the status inquiry unit 22; an AP determination unit 26 that determines a switching destination AP 12 based on data stored in the status list storage unit 24; And a communication control unit 28 that switches the communication connection destination based on the determination in the unit 26. In FIG. 2, seven APs 12 are shown, but there is no limit on the number of installed APs.

  FIG. 3 is a diagram illustrating an example of communication state data that is a part of the status stored in the status list storage unit 24. The status list storage unit 24 shows an example in which the wireless communication terminal 10 stores the status information of seven APs 12. Data stored in the status list storage unit 24 is “BD address”, “connection state”, “RSSI”, “Link Quality”, and “connection load”.

  The “BD address” is a Bluetooth device address, which identifies the AP 12. The “connection state” is data indicating whether or not connected to the AP 12 specified by the “BD address”. In this example, it is connected to the AP 12 with the BD address “0000ABC10001”. “RSSI” is data indicating the electric field strength of radio waves from the AP 12. The larger the value, the stronger the electric field strength. “Link Quality” is data indicating channel quality between the AP 12 and the terminal. The larger the value, the better the line quality. “Connection load” is data indicating the number of slaves connected to the AP 12.

  The data of “RSSI”, “Link Quality”, and “connection load” change from moment to moment. The wireless communication terminal 10 inquires each AP 12 for the latest state at any time, and updates the obtained result in the status list storage unit 24. The status acquisition timing may be regular or random. Further, the user may arbitrarily set the acquisition timing.

  Further, the status list storage unit 24 has “rank” data. The rank is data indicating the priority of connection among the plurality of APs 12. In the present embodiment, the rank is determined based on the RSSI value. That is, the higher priority is set in order from the largest RSSI value. When there are APs 12 having the same RSSI value, the rank is determined based on the Link Quality. When both RSSI and Link Quality have the same value, the order is determined based on the connection load.

  Next, the operation of the wireless communication terminal 10 according to the present embodiment will be described. FIG. 4 is a diagram illustrating a main flow of the wireless communication terminal 10. First, when the application of the wireless communication terminal 10 is activated, the wireless communication terminal 10 starts communication line control of the AP 12 (S10). Next, the wireless communication terminal 10 performs various application processes (S12) and performs communication line control when the wireless communication terminal 10 moves (S14). The wireless communication terminal 10 performs the application process (S12) and the communication line control (S14) in parallel until the line control ends (S16). In the application process, for example, when receiving a moving image distribution, the wireless communication terminal 10 performs an application process for displaying a moving image. Next, the detailed operation of the wireless communication terminal 10 in the communication line control (S14) will be described.

  FIG. 5 is a diagram illustrating an operation in which the wireless communication terminal 10 inquires the AP 12 in the vicinity about the status and stores the status based on the result. First, the wireless communication terminal 10 searches for nearby APs 12 (S20). The wireless communication terminal 10 searches for the AP 12 using an inquiry defined by the Bluetooth protocol.

  Next, the wireless communication terminal 10 acquires the status of the searched AP 12 (S22). Specifically, the wireless communication terminal 10 uses the status inquiry unit 22 to inquire about the status of the AP 12 and receives an inquiry response from the AP 12. If the inquiry connection to the AP 12 fails, the inquiry is retried. Here, the timeout time for determining whether or not the connection has failed, the number of connection retries, the connection retry interval, and the like can be arbitrarily set by the user.

  When receiving the inquiry response from the AP 12, the wireless communication terminal 10 reads the status of the AP 12 from the received inquiry response and stores it in the status list storage unit 24 (S24). The wireless communication terminal 10 updates the status of the nearby AP 12 by performing the above operation as needed, and stores it in the status list storage unit 24.

  FIG. 6 is a diagram illustrating an operation in which the wireless communication terminal 10 switches the AP 12. First, the wireless communication terminal 10 determines whether a communication line is connected to any AP 12 (S30). If it is determined by this determination that the communication line is connected (YES in S30), status information of the connected AP 12 is acquired (S32). The wireless communication terminal 10 determines whether or not the acquired status is appropriate for continuing communication (S34). For example, the wireless communication terminal 10 determines that the status is OK when the state of the radio wave from the connected AP 12 exceeds a preset threshold value, and determines that the status is NG when the state is equal to or less than the threshold value. If it is determined that the status is OK (YES in S34), the wireless communication terminal 10 proceeds to determination (S30) of whether or not the communication line is connected.

  If the status of the connected AP 12 is NG (NO in S34), the wireless communication terminal 10 reads the status list of the other AP 12 from the status list storage unit 24 (S36). Then, the status information is transferred to the AP determination unit 26, and the AP determination unit 26 determines the communication switching destination AP 12 based on the status list (S38). Then, the communication control unit 28 of the wireless communication terminal 10 switches the communication to the determined switching destination AP 12 (S40). By the above operation, when the status of the connected AP 12 is not good, it is possible to switch to the AP 12 having a good status. Further, as shown in FIG. 6, when the communication line connection is not performed (NO in S30), that is, when the wireless communication terminal 10 starts communication for the first time, the communication connection destination is based on the status list. AP12 can be determined (S36 to S40). The wireless communication terminal 10 according to the first embodiment has been described above.

  The wireless communication terminal 10 according to the present embodiment stores the statuses of a plurality of APs 12 different from the communication-connected APs 12 in the status list storage unit 24, so that the statuses of the plurality of APs 12 other than the communication connection are grasped. can do. When the radio wave state from the communication-connected AP 12 is deteriorated below a predetermined threshold, the switching destination access point AP12 is determined based on the status data stored in the status list storage unit 24. The communication connection can be switched.

  In addition, since the wireless communication terminal 10 according to the present embodiment determines the switching destination based on the status of the AP 12, the wireless communication terminal 10 can perform switching control. Thereby, the switching process can be performed regardless of the communication state between the AP 12 and the communication partner terminal 14, and the burden of the switching process can be distributed to the plurality of wireless communication terminals 10.

  In the first embodiment described above, the wireless communication terminal 10 is connected to the AP 12c and acquires the statuses of the APs 12a, 12b, and 12d that are not in communication connection as needed, but all the APs 12a to 12d that are within the communication range. It is good also as a structure which determines the AP12 which communicates and connects via the communication from among them. With this configuration, when switching the AP 12 via communication, it is not necessary to reconnect to the switching destination AP 12, so that the AP 12 can be switched smoothly. In this case, it is preferable to connect the AP 12 having a good status and connecting the AP 12 having a poor status in the low power consumption mode. Thereby, the connection load of the radio | wireless communication terminal 10 and AP12 can be reduced.

(Second Embodiment)
FIG. 7 is a diagram illustrating a configuration of the wireless communication terminal 10 according to the second embodiment. The wireless communication terminal 10 of the second embodiment has the same basic configuration as the wireless communication terminal 10 of the first embodiment, but is referred to as an access point information storage unit (hereinafter referred to as “AP information storage unit”). ) 30 is different from the remote host name stored in the status list storage unit 24.

  FIG. 8 is a diagram illustrating an example of data which is a part of the status stored in the status list storage unit 24 in the second embodiment. The status list storage unit 24 stores “remote host name” data in addition to the status data in the first embodiment. The remote host name is a name given to the AP 12. By assigning a remote host name, an access point can be easily specified in maintenance or the like.

  FIG. 9 is a diagram illustrating an example of data stored in the AP information storage unit 30. The AP information storage unit 30 stores information obtained by grouping a plurality of APs 12. The grouping of the APs 12 is performed according to the location of the AP 12, for example. In the present embodiment, AP 12 on the first floor of the building is group A and AP 12 on the second floor is group B. The group of the AP information storage unit 30 is updated based on the user setting. For example, when the AP 12 is added or changed, it is updated according to user settings.

  An operation of switching the AP 12 by the wireless communication terminal 10 according to the second embodiment configured as described above will be described. The basic operation of AP 12 switching is the same as in the first embodiment, but the method of determining the switching destination AP 12 is different.

  In the present embodiment, when the radio wave condition of the AP 12 that is in communication connection deteriorates, the AP 12 that belongs to the same group as the AP 12 that is in communication connection is read from the AP information storage unit 30. In the example illustrated in FIG. 8, the wireless communication terminal 10 is connected to the AP 12 having the remote host name “AP1”. Referring to the AP information storage unit 30 shown in FIG. 9, since “AP1” belongs to group A, the AP determination unit 26 reads “AP2” and “AP4” belonging to group A. Then, the AP 12 having the best status among the read APs 12 is determined as the switching destination.

  In the wireless communication terminal 10 according to the second embodiment, since the switching destination AP 12 is determined from the same group, only the AP 12 in the same location is a switching destination candidate. That is, since it is not necessary to check the statuses of the APs 12 in different locations, the processing burden when determining the switching destination AP 12 can be reduced.

  In addition, the wireless communication terminal 10 according to the second embodiment has an effect that communication switching can be performed under the initiative of the wireless communication terminal 10 in the same manner as the wireless communication terminal 10 according to the first embodiment.

  In the second embodiment, only the status of the AP 12 belonging to the same group as the communication-connected AP 12 may be acquired at any time. As a result, status inquiry processing can be reduced.

  The wireless communication terminal of the present invention has been described in detail with reference to the embodiment, but the present invention is not limited to the above-described embodiment.

  In the above-described embodiment, FIG. 3 and FIG. 8 show examples of data stored in the status list storage unit 24. However, data stored in the status list storage unit is not limited to the data described above. For example, a time interval or a pause time for an inquiry to the AP 12 may be stored. In addition, for example, application download information such as data download and upload completion rates and data types being communicated may be stored. As a result, it is possible to predict the time at which the processing during communication is completed, so that it can be used to determine the switching destination AP 12.

  In the embodiment described above, the priority order of the switching destination AP 12 is determined by determining the numerical values in the order of “RSSI”, “Link Quality”, and “connection load”. However, the priority order of the switching destination AP 12 is determined. Another method may be used as the determination method. For example, a weighting factor is set for each of “RSSI”, “Link Quality”, and “connection load”, a weighting factor is weighted to each numerical value, a total score is calculated, and a priority order is determined based on the total score. Good.

  As described above, the present invention has an excellent effect of performing switching control led by a wireless communication terminal and distributing the load of switching processing to each wireless communication terminal, and the line of a wireless communication terminal having a Bluetooth communication function. Suitable for switching methods.

The figure which shows the structure of the radio | wireless communication terminal of 1st Embodiment. The figure which shows the structure of the radio | wireless communications system to which a radio | wireless communication terminal is applied. The figure which shows the example of the data memorize | stored in the status list memory | storage part The figure which shows operation | movement of the radio | wireless communication terminal of 1st Embodiment The figure which shows the operation | movement which the radio | wireless communication terminal of 1st Embodiment produces | generates a status list The figure which shows the switching operation | movement of the access point by the radio | wireless communication terminal of 1st Embodiment The figure which shows the structure of the radio | wireless communication terminal of 2nd Embodiment. The figure which shows the example of the data memorize | stored in the status list memory | storage part The figure which shows the example of the data memorize | stored in the access point information storage part

Explanation of symbols

1 wireless communication system 10 wireless communication terminal 12 access point 14 remote host 20 radio wave state monitoring unit 22 status inquiry unit 24 status list storage unit 26 access point determination unit 28 communication control unit 30 access point information storage unit

Claims (7)

A wireless communication terminal that performs communication by Bluetooth,
Radio wave condition monitoring means for monitoring the radio wave condition from the access point being connected,
Status inquiry means for acquiring the status of a plurality of access points different from the access point that is in communication connection;
Status storage means for storing the status of each access point acquired by the status inquiry means;
An access that determines a switching destination access point based on the status of each access point stored in the status storage means when the state of the radio wave being monitored by the radio wave condition monitoring means deteriorates below a predetermined threshold value Point determination means;
Connection switching means for switching the connection to the access point determined by the access point determination means;
A wireless communication terminal comprising:   The wireless communication terminal according to claim 1, wherein the status inquiry unit makes an inquiry about status to the plurality of access points as needed. A wireless communication terminal that performs communication by Bluetooth,
Multiple connection means for connecting to multiple access points;
Status inquiry means for obtaining the status of each of the plurality of access points;
Status storage means for storing the status of each access point acquired by the status inquiry means;
Access point determination means for determining an access point via communication based on the status of each access point stored in the status storage means;
Communication means for performing communication via the access point determined by the access point determination means;
A wireless communication terminal comprising:   The wireless communication terminal according to claim 3, wherein the status inquiry means inquires of the plurality of access points for status as needed.   The plurality of access points connected by the plurality of connection means are divided into an access point connected in an active mode and an access point connected in a low power consumption mode according to a status. Wireless communication terminal. A wireless communication terminal that performs communication by Bluetooth,
Access point information storage means storing information obtained by grouping a plurality of access points;
Radio wave condition monitoring means for monitoring the radio wave condition from the access point being connected,
Status inquiry means for acquiring the status of a plurality of access points different from the access point that is in communication connection;
Status storage means for storing the status of each access point acquired by the status inquiry means;
When the state of the radio wave being monitored by the radio wave state monitoring unit deteriorates below a predetermined threshold, the access point belonging to the same group as the access point currently connected to the communication is read from the access point information storage unit, and the read access point An access point determination means for determining a switching destination access point based on the status of each access point stored in the status storage means,
Connection switching means for switching the connection to the access point determined by the access point determination means;
A wireless communication terminal comprising: A wireless communication terminal that performs communication by Bluetooth,
Status inquiry means for obtaining the status of multiple access points;
Status storage means for storing the status of each access point acquired by the status inquiry means;
An access point determination unit that determines an access point to be connected based on the status of each access point stored in the status storage unit;
A wireless communication terminal comprising: