JP4712534B2 - Mobile communication system, radio control server, and radio communication terminal - Google Patents

Description

  The present invention relates to a mobile communication system composed of different wireless communication systems, and more particularly to a mobile communication system that executes a data transmission rate change or a handover based on a moving state of a wireless communication terminal. .

  Mobile communication systems use different wireless communication systems such as W-CDMA (Wideband Code Division Multiple Access), cdma2000, and W-LAN (Wireless Local Area Network). Each of these wireless communication systems has different characteristics such as the size of a communication area (cell) covered by one base station and the maximum communication speed. When a plurality of wireless communication systems are connected to each other by IP (Internet Protocol) or the like, and one wireless communication terminal is equipped with wireless interfaces of a plurality of different wireless communication systems, the different wireless communication systems are integrated. By handling, it is possible for a wireless communication terminal to perform handover between wireless communication systems.

  For example, Japanese Patent Application Laid-Open No. 2004-151826 is known as a related art regarding handover between different wireless communication systems. In the prior art described in Patent Document 1, radio access system information including frequencies used by different radio communication systems (radio access systems), cell identifiers and report thresholds, and radio resources for calculating communication suitability The radio resource management device that manages the information in a unified manner for each radio access system instructs the radio communication terminal to measure the reception level of each radio access system based on the radio access system information, and the radio communication terminal measures the reception Based on the level and radio resource information, the communication appropriateness of each cell is calculated to determine whether to perform handover.

  By the way, the wireless communication terminal moves in the communication area (cell) covered by the base station, but the communication environment between the wireless communication terminal and the base station changes due to this movement. As a result, the communication environment deteriorates, transmission performance decreases, and the frequency of occurrence of communication errors may increase. In particular, when the wireless communication terminal is moving at high speed, a change in the communication environment becomes large and communication errors frequently occur. Also, the higher the communication speed between the wireless communication terminal and the base station, the greater the influence of environmental changes.

  Further, there is a case where data destined for the radio communication terminal is discarded during handover execution, that is, while the base station to which the radio communication terminal is connected is changed, and discarding this data is one of the causes of communication errors. For example, in a wireless communication system characterized by a narrow cell range, such as a wireless communication system using a W-LAN scheme, communication errors increase because handover is frequently performed.

  In a mobile communication system that realizes high-speed communication, it is required to reduce communication errors, and various techniques for reducing communication errors are considered. For example, in Patent Document 2, in a communication system in which the data communication speed in the downlink direction from a base station to a wireless communication terminal varies greatly depending on the reception level of a base station signal in the wireless communication terminal, the wireless communication terminal is provided in its own station Information on position detection function such as GPS (Global Positioning System) is transmitted to the base station at a predetermined frequency, and the downlink direction within a predetermined time from the present time based on the position information received by the base station and the movement information calculated from the position information A technique is disclosed in which the fluctuation prediction information of the data communication speed is calculated and notified to the wireless communication terminal, and the wireless communication terminal displays the fluctuation prediction information on its own display means.

JP 2004-349976 A JP 2002-353876 A

  However, in the prior art described in Patent Document 1, the radio resource management apparatus instructs handover based on the reception level and radio resource information of each radio communication system measured by the radio communication terminal. If handover cannot be performed because there is only one wireless communication system that can be used by the wireless communication terminal at the present time, the wireless resource management apparatus may instruct the wireless communication terminal to perform handover. Can not. For this reason, there is a problem that the measurement result cannot be used effectively and the occurrence of a communication error cannot be prevented in advance.

  In the prior art described in Patent Document 2, the fluctuation prediction information of the data communication speed in the downlink direction within a predetermined time from the present time based on the position information measured by the position detection function and the movement information calculated from the position information. For example, when GPS is used as the position detection function, the wireless communication terminal may be present indoors or at a position that is a shadow of a building and cannot acquire accurate information from GPS satellites. There was a problem in the reliability of the fluctuation prediction information.

  Furthermore, in the prior art described in Patent Document 2, since the wireless communication terminal displays the fluctuation prediction information, it can be recognized from the fluctuation prediction information that the communication speed is reduced. However, a technique for preventing in advance a communication error that occurs due to a decrease in communication speed is not disclosed.

  The present invention has been made in view of the above, and predicts an available bandwidth of a wireless communication terminal moving through a plurality of different wireless communication systems, and performs communication at an optimal data transmission rate to suppress communication errors. It is a first object to obtain a mobile communication system.

  A second object is to provide a mobile communication system that suppresses communication errors by selecting an optimal wireless communication system for a wireless communication terminal moving through a plurality of different wireless communication systems and performing handover. It is.

  In order to solve the above-described problems and achieve the object, the present invention provides a radio control server capable of communicating with a plurality of different radio communication systems and a radio communication terminal capable of communicating with at least one of the plurality of different radio communication systems. In order to identify the wireless communication system used by the mobile terminal, the wireless communication terminal measures the mobile terminal's movement state, and obtains the movement state information obtained from the measured movement state. A wireless communication system identifier, a measurement result information including the available bandwidth of the terminal itself, and a mobile state measurement unit that notifies the wireless control server of the measurement result information, and an available bandwidth information notified from the wireless control server A wireless control unit that changes a data transmission rate to the wireless communication system being used based on the estimated available bandwidth included, The wireless control server includes an available bandwidth predicted value information table in which an available bandwidth predicted value is registered in association with a wireless communication system identifier and movement state information for identifying the different wireless communication systems, and the wireless communication A search unit for acquiring a usable bandwidth predicted value corresponding to a wireless communication system identifier and movement state information included in measurement result information notified from a terminal from the usable bandwidth predicted value information table; and When the obtained estimated usable bandwidth value matches the usable bandwidth in the measurement result information notified from the wireless communication terminal, the usable bandwidth of the wireless communication terminal is suitable. If the available bandwidth acquired by the search unit and the current available bandwidth in the measurement result information notified from the wireless communication terminal do not match Is determined that the available bandwidth of the wireless communication terminal is incompatible, and if it is determined to be incompatible, the available bandwidth information including the estimated available bandwidth acquired by the search unit A wireless determination unit that notifies the wireless communication terminal of the wireless communication terminal.

  According to the present invention, the wireless communication terminal measures the acceleration of its own terminal, and includes the measured acceleration, the wireless communication system identifier for identifying the wireless communication system currently used, and the current available bandwidth. Measurement result information is generated and notified to the wireless control server. The radio control server uses the measurement result information notified from the radio communication terminal, and the available bandwidth information table in which the available bandwidth prediction value is registered in association with the radio communication system identifier and the acceleration information. The available bandwidth of the wireless communication terminal is predicted to determine the adaptability of the current available bandwidth. If it is determined that the wireless bandwidth is not compatible, the predicted available bandwidth (the estimated available bandwidth) is The available bandwidth information is notified to the wireless communication terminal, and the data transmission rate of the wireless communication terminal is changed. That is, based on the acceleration indicating the movement state of the wireless communication terminal, the available bandwidth is predicted and the data transmission rate is changed. Thereby, it is possible to suppress a communication error that occurs due to a change in the communication environment due to movement of the wireless communication terminal, and it is possible to obtain a mobile communication system that can improve throughput.

  Hereinafter, embodiments of a mobile communication system, a radio control server, and a radio communication terminal according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a configuration of a mobile communication system according to a first embodiment of the present invention. In FIG. 1, a mobile communication system uses a communication area 22 as a communicable range and a base station 20 connected to the core network 40 using IP (Internet Protocol), etc. A base station 21 that is connected to the core network 40 by using the base station 20, 21 and the base station 20, 21 and the core network 40, and the wireless control server 30 and a communication partner (not shown) via the base station 20, 21 and the core network 40. And a wireless communication terminal 10 that performs mutual communication with the communication terminal.

  The base station 20 is a base station compatible with a wireless communication system based on W-CDMA (Wideband Code Division Multiple Access), and the base station 21 is a base station compatible with a wireless communication system based on W-LAN (Wireless Local Area Network). The communication area 23 covered by the base station 21 exists in the communication area 22 covered by the base station 20.

  FIG. 2 is a block diagram showing a configuration of the wireless communication terminal 10 shown in FIG. In FIG. 2, a wireless communication terminal 10 includes a wireless interface unit (hereinafter referred to as a wireless I / F unit) 16-1 having a W-CDMA wireless interface function and used for connection to a base station 20, A wireless interface unit (hereinafter referred to as a wireless I / F unit) 16-2 having a LAN wireless interface function and used for connection with the base station 21, and an acceleration sensor 15 for measuring acceleration in a moving state; The sensor interface unit (hereinafter referred to as sensor I / F unit) 12 having an interface function with the acceleration sensor 15 and the measurement value (acceleration) of the acceleration sensor 15 are acquired through the sensor I / F unit 12 and acquired. A sensor information measuring unit 13 that is a moving state measuring unit that creates measurement result information in which predetermined information is added to the measured acceleration, and the core network 40. Of the communication protocol (in this case, IP), generates an IP frame from the measurement result information created by the sensor information measurement unit 13, communication data with the communication partner, and the like. A network interface unit (hereinafter referred to as a network I / F unit) 11 for transmitting an IP frame including an available bandwidth information frame and communication data, and a network 11 A wireless control unit that controls the data communication rate based on the estimated available bandwidth value in the available bandwidth information received by the I / F unit.

  The radio control server 30 manages all radio communication systems constituting the mobile communication system in a unified manner. FIG. 3 is a block diagram showing a configuration of the radio control server 30 shown in FIG. In FIG. 3, the radio control server 30 has an interface function of the core network 40, receives a measurement result information transmitted from the radio communication terminal 10, and transmits a usable bandwidth information (hereinafter referred to as a network). I / F unit) 33, a storage unit 34 for storing an information table necessary for selecting an estimated available bandwidth, and measurement result information received via the network I / F unit 33 and the storage unit 34 A search unit 31 that searches for an available bandwidth prediction value based on an information table to be stored, an available bandwidth prediction value searched by the search unit 31, and a current available bandwidth in measurement result information The available bandwidth information including the available bandwidth predicted value based on the determination result by determining the adaptability of the available bandwidth of the wireless communication terminal 10 And a determining radio determination section 32 whether or not to transmit to the radio communication terminal 10.

  FIG. 4 is a diagram illustrating an available bandwidth information table that is an information table stored in the storage unit 34 of the wireless control server 30 illustrated in FIG. 3. In FIG. 4, the available bandwidth information table includes a wireless communication system type in which an identifier (in this case, the name of the wireless communication system) for identifying a wireless communication system managed by the wireless control server 30 is registered, and acceleration. Is registered, and an available bandwidth in which a predicted available bandwidth, which is a predicted value of a usable bandwidth in association with the type of wireless communication system and the acceleration information, is registered.

  Next, the operation of the first embodiment of the mobile communication system according to the present invention will be described with reference to the sequence diagram of FIG. 5 and FIGS. It is assumed that the wireless communication terminal 10 is communicating with the base station 20 using the wireless I / F unit 16-1.

  When the predetermined measurement time is reached, the sensor information measurement unit 13 of the wireless communication terminal 10 measures the acceleration of the terminal itself (step S100). Specifically, the value (acceleration) of the acceleration sensor 15 is acquired via the sensor I / F unit 12. The sensor information measurement unit 13 includes a measured acceleration, a terminal identifier (ID) assigned to the terminal in advance, and a wireless communication system identifier (in this case, W−) indicating the wireless communication system currently used by the terminal. Measurement result information including CDMA) and the current available bandwidth (available bandwidth notified from the previous radio control server 30) is created (step S101). The sensor information measurement unit 13 outputs the created measurement result information to the network I / F unit 11.

  The network I / F unit 11 of the wireless communication terminal 10 transmits a measurement result information frame from the measurement result information (a wireless control server corresponding to IP which is a communication protocol of the core network 40 for notifying the wireless control server 30 of the measurement result information). 30) and the generated measurement result information frame is transmitted via the wireless I / F unit 16-1 currently used (step S102). The measurement result information frame reaches the radio control server 30 via the base station 20 and the core network 40.

  When receiving the measurement result information frame, the network I / F unit 33 of the wireless control server 30 extracts the measurement result information from the received measurement result information frame, and outputs the extracted measurement result information to the search unit 31.

  The search unit 31 of the radio control server 30 searches the radio communication system type and acceleration information in the available bandwidth information table stored in the storage unit 34 using the radio communication system identifier and acceleration in the measurement result information as search keys. Then, an available bandwidth prediction value registered in the available bandwidth of the available bandwidth information table in association with the wireless communication system type and acceleration information matching the search key is acquired (step S103). The search unit 31 outputs the acquired available bandwidth predicted value and measurement result information to the wireless determination unit 32.

  The wireless determination unit 32 of the wireless control server 30 matches the available bandwidth of the wireless communication terminal 10 based on the current available bandwidth in the measurement result information and the estimated available bandwidth acquired by the search unit 31. Is determined (step S104). Specifically, the wireless determination unit 32 compares the current available bandwidth in the measurement result information with the available bandwidth predicted value acquired by the search unit 31, and when the comparison results match. Determines that the available bandwidth of the wireless communication terminal 10 is compatible, and determines that the available bandwidth of the wireless communication terminal 10 is incompatible if the comparison result does not match. When the determination result is incompatible, the wireless determination unit 32 generates usable bandwidth information including the estimated usable bandwidth value acquired by the search unit 31, and uses the generated usable bandwidth information as the network I / F unit. To 33.

  The network I / F unit 33 of the wireless control server 30 uses an available bandwidth information frame (IP that is a communication protocol of the core network 40 for notifying the wireless communication terminal 10 of the available bandwidth information) from the available bandwidth information. And a generated usable bandwidth information frame is transmitted to the core network 40 (step S105). The available bandwidth information frame reaches the wireless communication terminal 10 via the core network 40 and the base station 20.

  When the available bandwidth information frame is received via the wireless I / F unit 16-1 of the wireless communication terminal 10, the network I / F unit 11 extracts the available bandwidth information from the received available bandwidth information frame. The extracted usable bandwidth information is output to the wireless control unit 14.

  The wireless control unit 14 of the wireless communication terminal 10 changes the data transmission rate based on the available bandwidth information from the network I / F unit 11 (step S106). Specifically, the radio control unit 14 selects the data transmission rate based on the bandwidth requested by the currently executing application, with the estimated available bandwidth included in the available bandwidth information as the upper limit. . The wireless control unit 14 notifies the currently used wireless I / F unit 16-1 of the selected data transmission rate, and the wireless I / F unit 16-1 subsequently performs the network I / F at the notified data transmission rate. The frame from the unit 11 is transmitted.

  As described above, in the first embodiment, the wireless communication terminal 10 measures the acceleration of its own terminal, the measured acceleration, the wireless communication system identifier for identifying the wireless communication system currently used, And the measurement result information including the current available bandwidth is generated and notified to the radio control server 30. The wireless control server 30 uses the measurement result information notified from the wireless communication terminal 10 and the available bandwidth information table in which the available bandwidth prediction value is registered in association with the wireless communication system identifier and the acceleration information. Thus, the available bandwidth of the wireless communication terminal 10 is predicted to determine the adaptability of the current available bandwidth, and when it is determined that the wireless bandwidth is not suitable, the predicted available bandwidth (available bandwidth prediction The available bandwidth information including the value) is notified to the wireless communication terminal 10 to change the data transmission rate of the wireless communication terminal 10. That is, based on the acceleration indicating the movement state of the wireless communication terminal 10, the available bandwidth is predicted and the data transmission rate is changed. Thereby, the communication error which generate | occur | produces by the change of the communication environment by the movement of the radio | wireless communication terminal 10 can be suppressed, and a through-put can be improved.

  In the first embodiment, the W-CDMA wireless communication system and the W-LAN wireless communication system have been described as examples. However, the wireless communication system is not limited thereto.

  In the first embodiment, the wireless communication terminal 10 includes a wireless I / F unit 16-1 having a W-CDMA interface function and a wireless I / F unit having a W-LAN wireless interface function. However, the wireless communication terminal 10 only needs to have a wireless interface function of at least one wireless communication system among different wireless communication systems constituting the mobile communication system.

  Furthermore, in the first embodiment, the radio communication terminal 10 transmits the measurement result information to the radio control server 30 every time the acceleration is measured, but a predetermined constant time period or acceleration is predetermined. The measurement result information may be transmitted to the wireless control server 30 only when the set threshold value is exceeded. Thereby, the frequency | count of transmission of measurement result information can be reduced and radio | wireless utilization efficiency can be improved.

  In the first embodiment, the acceleration measured as the movement state information is used. However, the movement speed obtained by integrating the acceleration may be used. In this case, the sensor information measuring unit 13 integrates the acceleration measured from the acceleration sensor 15 via the sensor I / F unit 12 to obtain the moving speed, and includes the obtained moving speed in the measurement result information instead of the acceleration. To. Moreover, what is necessary is just to register a moving speed in the available bandwidth information table memorize | stored in the memory | storage part 34 instead of acceleration information.

Embodiment 2. FIG.
A second embodiment of the present invention will be described with reference to FIGS. The mobile communication system according to the second embodiment of the present invention includes a radio communication terminal 10a instead of the radio communication terminal 10 of the mobile communication system according to the first embodiment shown in FIG. Instead, a wireless control server 30a is provided.

  FIG. 6 is a block diagram showing a configuration of a radio communication terminal 10a applied to the mobile communication system of the second embodiment. In the radio communication terminal 10a shown in FIG. 6, a bandwidth information storage unit 17 and a movement speed calculation unit 18 are added to the radio communication terminal 10 of the first embodiment shown in FIG. Components having the same functions as those of the wireless communication terminal 10 of the first embodiment shown in FIG. 2 are given the same reference numerals, and redundant descriptions are omitted.

  The movement speed calculation unit 18 integrates the acceleration measured by the sensor information measurement unit 13 and calculates the movement speed of the terminal itself. The bandwidth information storage unit 17 stores the current available bandwidth.

  The sensor information measurement unit 13 uses the movement speed at the current measurement time calculated by the movement speed calculation unit 18, the acceleration at the measured current measurement time, a terminal identifier assigned to the terminal in advance, and the terminal currently in use. Measurement result information including the wireless communication system identifier indicating the wireless communication system and the current available bandwidth stored in the bandwidth information storage unit 17 is created.

  FIG. 7 is a block diagram showing a configuration of radio control server 30a applied to the mobile communication system of the second embodiment. In the radio control server 30a shown in FIG. 7, the storage unit 34 is deleted from the radio control server 30 of the first embodiment shown in FIG. 3, and a bandwidth calculation unit 35 is added instead of the search unit 31. Yes. Components having the same functions as those of the wireless control server 30 of the first embodiment shown in FIG. 3 are given the same reference numerals, and redundant descriptions are omitted.

The bandwidth calculation unit 35 calculates a future available bandwidth (a predicted available bandwidth value from the moving speed at the current measurement time in the measurement result information received via the network I / F unit 33 and the acceleration at the current measurement time. ) Is calculated. If the current measurement time is t, the current available bandwidth is R (t), and the amount of change is γ, the future available bandwidth R (t + 1) is
R (t + 1) = R (t) + γ (1)
Can be expressed as If the acceleration at the current measurement time is a and the moving speed at the current measurement time is v (t), the change amount γ is
γ = −k × | a | × | v (t) | × R (t) (2)
Can be expressed as Note that k is a predetermined constant. The bandwidth calculation unit 35 calculates the future available bandwidth from the various pieces of information in the measurement result information using the above formulas (1) and (2).

  Next, the operation of the second embodiment of the mobile communication system according to the present invention will be described with reference to the sequence diagram of FIG. 8 and the previous FIG. 1, FIG. 6, and FIG. Detailed description of the same operation as in the first embodiment will be omitted. In addition, it is assumed that the wireless communication terminal 10a communicates by connecting to the base station 20 using the wireless I / F unit 16-1.

  When the predetermined measurement time is reached, the sensor information measurement unit 13 of the wireless communication terminal 10a measures the acceleration of the terminal itself (step S200). The sensor information measurement unit 13 outputs the measured acceleration to the movement speed calculation unit 18.

  The movement speed calculation unit 18 of the wireless communication terminal 10a integrates the acceleration input from the sensor information measurement unit 13 to calculate the movement speed of the own terminal (step S201). The movement speed calculation unit 18 outputs the calculated movement speed to the sensor information measurement unit 13.

  The sensor information measurement unit 13 of the wireless communication terminal 10 a reads the current available bandwidth from the bandwidth information storage unit 17. The sensor information measuring unit 13 includes a moving speed (moving speed at the current measurement time) input from the moving speed calculating unit 18, an acceleration at the measured current measurement time, an identifier given to the own terminal in advance, and the own terminal currently using Measurement result information including a wireless communication system identifier (in this case, W-CDMA) indicating the wireless communication system being used and the current available bandwidth read from the bandwidth information storage unit 17 is created (step S202). The sensor information measurement unit 13 outputs the created measurement result information to the network I / F unit 11.

  The network I / F unit 11 of the wireless communication terminal 10a generates a measurement result information frame from the measurement result information, and transmits the generated measurement result information frame via the currently used wireless I / F unit 16-1 ( Step S203). The measurement result information frame reaches the radio control server 30a via the base station 20 and the core network 40.

  When receiving the measurement result information frame, the network I / F unit 33 of the wireless control server 30 a extracts the measurement result information from the received measurement result information frame, and outputs the extracted measurement result information to the bandwidth calculation unit 35.

  The bandwidth calculation unit 35 of the wireless control server 30a uses the moving speed at the current measurement time, the acceleration at the current measurement time, and the current available bandwidth in the measurement result information, and the above equations (1) and ( The future available bandwidth is calculated according to 2) (step S204). The bandwidth calculation unit 35 outputs the calculated future available bandwidth and the measurement result information to the wireless determination unit 32.

  The wireless determination unit 32 of the wireless control server 30a determines the available bandwidth of the wireless communication terminal 10a based on the current available bandwidth in the measurement result information and the future available bandwidth calculated by the bandwidth calculation unit 35. The fitness is determined (step S205). Specifically, the wireless determination unit 32 compares the current available bandwidth in the measurement result information with the future available bandwidth calculated by the bandwidth calculation unit 35, and the comparison results match. In this case, it is determined that the available bandwidth is compatible, and when the comparison result does not match, it is determined that the available bandwidth is incompatible. If the determination result is incompatible, the wireless determination unit 32 generates usable bandwidth information including the future usable bandwidth calculated by the bandwidth calculation unit 35, and uses the generated usable bandwidth information as the network I / O. Output to the F unit 33.

  The network I / F unit 33 of the radio control server 30a generates an available bandwidth information frame from the available bandwidth information, and transmits the generated available bandwidth information frame to the core network 40 (step S206). The available bandwidth information frame reaches the wireless communication terminal 10 a via the core network 40 and the base station 20.

  When the available bandwidth information frame is received via the wireless I / F unit 16-1 of the wireless communication terminal 10a, the network I / F unit 11 extracts the available bandwidth information from the received available bandwidth information frame. The extracted usable bandwidth information is output to the wireless control unit 14.

  The wireless control unit 14 of the wireless communication terminal 10a changes the data transmission rate based on the available bandwidth information from the network I / F unit 11 (step S207). In addition, the wireless control unit 14 sets the available bandwidth that is available bandwidth information from the network I / F unit 11 (usable bandwidth information finally notified from the wireless control server 30a) to the current available bandwidth. The bandwidth is stored in the bandwidth information storage unit 17 as a width.

  As described above, in the second embodiment, the wireless communication terminal 10a measures the acceleration of the own terminal, and the acceleration obtained by integrating the measured acceleration is given to the own terminal in advance. The wireless control server 30a is notified of the terminal identifier being used, the wireless communication system identifier indicating the wireless communication system currently used by the terminal itself, and the current available bandwidth. The radio control server 30a predicts the available bandwidth of the radio communication terminal 10a from the measurement result information notified from the radio communication terminal 10a by a calculation formula, determines the degree of adaptation of the current available bandwidth, and is incompatible. Is determined, the available bandwidth information including the predicted available bandwidth (usable bandwidth predicted value) is notified to the wireless communication terminal 10a, and the data transmission rate of the wireless communication terminal 10a is changed. That is, based on the acceleration indicating the movement state of the wireless communication terminal 10a, the available bandwidth is predicted and the data transmission rate is changed. Thereby, the communication error which generate | occur | produces by the change of the communication environment by movement of the radio | wireless communication terminal 10a can be suppressed, and a through-put can be improved.

Embodiment 3 FIG.
A third embodiment of the present invention will be described with reference to FIGS. The mobile communication system according to the third embodiment includes a radio control server 30b instead of the radio control server 30 of the mobile communication system according to the first embodiment shown in FIG.

  FIG. 9 is a block diagram showing a configuration of radio control server 30b applied to the mobile communication system of the third embodiment. The radio control server 30b shown in FIG. 9 includes a search unit 31a instead of the search unit 31 of the radio control server 30 of the first embodiment shown in FIG. 3, and a bandwidth calculation unit 35 is added. Yes. Components having the same functions as those of the wireless control server 30 of the first embodiment shown in FIG. 3 are given the same reference numerals, and redundant descriptions are omitted.

  The storage unit 34 of the wireless control server 30b according to the third embodiment stores a wireless communication terminal information table as an information table. FIG. 10 is a diagram showing a wireless communication terminal information table stored in the storage unit 34 of the wireless control server 30b according to the third embodiment. In FIG. 10, the wireless communication terminal information table registers the terminal ID in which the identifier of the wireless communication terminal 10 is registered, and the available bandwidth that was previously notified to the wireless communication terminal 10 in association with the terminal ID. With possible bandwidth.

  The search unit 31 a acquires the current available bandwidth based on the measurement result information notified from the wireless communication terminal 10 and the wireless communication terminal information table stored in the storage unit 34. The bandwidth calculation unit 35 uses the measurement result information and the current available bandwidth acquired by the search unit 31a to calculate the future available bandwidth by the above formulas (1) and (2).

  Next, the operation of the mobile communication system according to the third embodiment will be described with reference to the sequence diagram of FIG. 11, FIG. 1, FIG. 2, FIG. 9, and FIG. Detailed description of the same operations as those in the first or second embodiment will be omitted. Further, it is assumed that the wireless communication terminal 10 is communicating with the base station 20 using the wireless I / F unit 16-1.

  When the predetermined measurement time comes, the sensor information measurement unit 13 of the wireless communication terminal 10 measures the acceleration of the own terminal (step S301). The sensor information measurement unit 13 creates measurement result information including the measured acceleration and an identifier previously assigned to the own terminal (step S302). The sensor information measurement unit 13 outputs the created measurement result information to the network I / F unit 11.

  The network I / F unit 11 of the wireless communication terminal 10 generates a measurement result information frame from the measurement result information, and transmits the generated measurement result information frame via the currently used wireless I / F unit 16-1 ( Step S303). The measurement result information frame reaches the radio control server 30b via the base station 20 and the core network 40.

  When receiving the measurement result information frame, the network I / F unit 33 of the radio control server 30b extracts the measurement result information from the received measurement result information frame, and outputs the extracted measurement result information to the search unit 31a.

  The search unit 31a of the wireless control server 30b searches the terminal ID of the wireless communication terminal information table stored in the storage unit 34 using the terminal identifier of the wireless communication terminal 10 in the measurement result information as a search key, The current available bandwidth registered in the wireless communication terminal information table in association with the matching terminal ID is acquired (step S304). The search unit 31 a outputs the acquired current available bandwidth, previous available bandwidth, moving speed, and measurement result information to the bandwidth calculation unit 35.

  The bandwidth calculation unit 35 of the wireless control server 30b calculates the moving speed by integrating the acceleration in the measurement result information (step S305).

  The bandwidth calculation unit 35 of the wireless control server 30b uses the calculated moving speed as the moving speed at the current measurement time, the acceleration in the measurement result information as the acceleration at the current measurement time, and the current available bandwidth input from the search unit 31a. The future available bandwidth is calculated by the previous equations (1) and (2), with the width as the current available bandwidth (step S306). The bandwidth calculator 35 outputs the calculated future available bandwidth, the current available bandwidth (current available bandwidth) input from the search unit 31a, and the measurement result information to the wireless determination unit 32.

  The wireless determination unit 32 of the wireless control server 30b determines the adaptability of the available bandwidth of the wireless communication terminal 10 based on the current available bandwidth and the future available bandwidth input from the bandwidth calculation unit 35. (Step S307). Specifically, the wireless determination unit 32 compares the current available bandwidth with the future available bandwidth, and if the comparison results match, the available bandwidth of the wireless communication terminal 10 is It is determined that the wireless communication terminal 10 is compatible, and when the comparison result is inconsistent, it is determined that the available bandwidth of the wireless communication terminal 10 is incompatible.

  If the determination result is incompatible, the wireless determination unit 32 generates usable bandwidth information including the future usable bandwidth calculated by the bandwidth calculation unit 35, and uses the generated usable bandwidth information as the network I / O. Output to the F unit 33. The wireless determination unit 32 registers the future available bandwidth in the current available bandwidth of the wireless communication terminal information table in the storage unit 34 in association with the terminal identifier of the wireless communication terminal 10 in the measurement result information. That is, the wireless communication terminal information table is updated.

  The network I / F unit 33 of the radio control server 30b generates an available bandwidth information frame from the available bandwidth information, and transmits the generated available bandwidth information frame to the core network 40 (step S308). The available bandwidth information frame reaches the wireless communication terminal 10 via the core network 40 and the base station 20.

  When the available bandwidth information frame is received via the wireless I / F unit 16-1 of the wireless communication terminal 10, the network I / F unit 11 extracts the available bandwidth information from the received available bandwidth information frame. The extracted usable bandwidth information is output to the wireless control unit 14. The wireless control unit 14 changes the data transmission rate based on the available bandwidth information from the network I / F unit 11 (step S309).

  As described above, in the third embodiment, the wireless communication terminal 10 measures the acceleration of the own terminal, and the measurement result information including the measured acceleration and the terminal identifier for identifying the own terminal is transmitted to the wireless control server. 30b is notified. The wireless control server 30b can use the wireless communication terminal 10 using the measurement result information notified from the wireless communication terminal 10 and the wireless communication terminal information table in which the available bandwidth of the wireless communication terminal 10 is registered. The bandwidth is predicted by a calculation formula to determine the suitability of the current available bandwidth, and if it is determined to be non-conforming, it can be used including the predicted available bandwidth (the estimated available bandwidth). The bandwidth information is notified to the wireless communication terminal 10 to change the data transmission rate of the wireless communication terminal 10. That is, based on the acceleration indicating the movement state of the wireless communication terminal 10, the available bandwidth is predicted and the data transmission rate is changed. Thereby, the communication error which generate | occur | produces by the change of the communication environment by the movement of the radio | wireless communication terminal 10 can be suppressed, and a through-put can be improved.

Embodiment 4 FIG.
A fourth embodiment of the present invention will be described with reference to FIGS. In the first to third embodiments, the change of the data transmission rate in the same wireless communication system has been described. In the fourth embodiment, switching between wireless communication systems, that is, handover to a different wireless communication system will be described.

  The mobile communication system according to the fourth embodiment of the present invention is substantially the same as the mobile communication system according to the first embodiment shown in FIG. The difference between the mobile communication system of the first embodiment and the mobile communication system of the fourth embodiment is an information table stored in the storage unit 34 of the radio control server 30. The storage unit 34 of the wireless control server 30 according to the fourth embodiment has a wireless communication system necessary for determining whether or not to perform handover in addition to the available bandwidth information table shown in FIG. 4 as an information table. Store the type table.

  FIG. 12 shows a wireless communication system type table. In FIG. 12, the wireless communication system type table includes a current wireless communication system type in which a wireless communication system identifier (in this case, the name of the wireless communication system) of the current wireless communication system is registered, acceleration information in which acceleration is registered, and The wireless communication system type and the adaptive wireless communication system type in which the wireless communication system identifier indicating the wireless communication system to be adapted in association with the acceleration information is registered.

  Next, a handover operation of the mobile communication system according to the fourth embodiment will be described with reference to the sequence diagram of FIG. 13, FIGS. 1 to 4, and FIG. 12. It is assumed that the wireless communication terminal 10 is communicating with the base station 20 using the wireless I / F unit 16-1.

  When the predetermined measurement time is reached, the sensor information measurement unit 13 of the wireless communication terminal 10 measures the acceleration of the terminal itself (step S400). The sensor information measurement unit 13 includes a measured acceleration, a terminal identifier given to the terminal in advance, a wireless communication system identifier (in this case, W-CDMA) indicating a wireless communication system currently used by the terminal, and Measurement result information including the current available bandwidth is created (step S401). The sensor information measurement unit 13 outputs the generated measurement result information to the network I / F unit 11.

  The network I / F unit 11 of the wireless communication terminal 10 generates a measurement result information frame from the measurement result information, and transmits the generated measurement result information frame via the currently used wireless I / F unit 16-1 ( Step S402). The measurement result information frame reaches the radio control server 30 via the base station 20 and the core network 40.

  When receiving the measurement result information frame, the network I / F unit 33 of the wireless control server 30 extracts the measurement result information from the received measurement result information frame, and outputs the extracted measurement result information to the search unit 31.

  The search unit 31 of the radio control server 30 searches the current radio communication system type and acceleration information in the radio communication system type table stored in the storage unit 34 using the radio communication system identifier and acceleration in the measurement result information as search keys. Then, the wireless communication system identifier registered in the adaptive wireless communication system type of the wireless communication system type table in association with the current wireless communication system type and acceleration information matching the search key is acquired (step S403). The search unit 31 outputs the acquired wireless communication system identifier and measurement result information to the wireless determination unit 32.

  The radio determination unit 32 of the radio control server 30 is adapted to the radio communication system currently used by the radio communication terminal 10 based on the radio communication system identifier in the measurement result information and the radio communication system identifier acquired by the search unit 31. Is determined (step S404). Specifically, the wireless determination unit 32 compares the wireless communication system identifier (currently used wireless communication system) in the measurement result information with the wireless communication system identifier acquired by the search unit 31, and the comparison result is obtained. If they match, it is determined that the radio communication system of the radio communication terminal 10 is compatible, and if the comparison results do not match, it is determined that the radio communication system of the radio communication terminal 10 is not compatible.

  When the determination result is incompatible, the wireless determination unit 32 of the wireless control server 30 generates system switching information including the wireless communication system identifier acquired by the search unit 31, and uses the generated system switching information as the network I / F unit 33. Output to.

  The network I / F unit 33 of the wireless control server 30 corresponds to the system switching information frame from the system switching information (IP which is a communication protocol of the core network 40 for notifying the wireless communication terminal 10 of system switching, that is, handover) A frame addressed to the wireless communication terminal 10 is generated, and the generated system switching information frame is transmitted to the core network 40 (step S405). The system switching information frame reaches the wireless communication terminal 10 via the core network 40 and the base station 20.

  When the available bandwidth information frame is received via the wireless I / F unit 16-1 of the wireless communication terminal 10, the network I / F unit 11 extracts the available bandwidth information from the received available bandwidth information frame. The extracted usable bandwidth information is output to the wireless control unit 14.

  The wireless control unit 14 of the wireless communication terminal 10 changes the wireless communication system to be used based on the system switching information from the network I / F unit 11 (step S406). Specifically, since the wireless communication terminal 10 currently uses a wireless communication system based on the W-CDMA system, the wireless communication system of the wireless communication system based on the W-LAN system is notified in the system switching information. Therefore, the wireless control unit 14 of the wireless communication terminal 10 executes a general handover process for switching the connection from the base station 20 of the wireless communication system using the W-CDMA method to the base station 21 of the wireless communication system using the W-LAN method. .

  On the other hand, when it is determined that the wireless communication system is compatible, the wireless determination unit 32 of the wireless control server 30 outputs an instruction for requesting the available bandwidth to the search unit 31. When receiving the instruction for requesting the available bandwidth, the search unit 31 executes the process of acquiring the available bandwidth predicted value in step S103 described with reference to the sequence diagram of FIG. The wireless determination unit 32 executes the usable bandwidth suitability determination process in step S104, and based on the determination result, the wireless control server 30 transmits an available bandwidth information frame, so that the wireless communication terminal 10 Change the data transmission rate.

  As described above, in the fourth embodiment, the wireless communication terminal 10 measures the acceleration of the terminal itself, the measured acceleration, the wireless communication system identifier for identifying the wireless communication system currently used, And the measurement result information including the current available bandwidth is generated and notified to the radio control server 30. The radio control server 30 has a radio communication system identifier indicating a radio communication system adapted to be associated with measurement result information notified from the radio communication terminal 10, a radio communication system identifier indicating the current radio communication system, and acceleration information in advance. Using the registered radio communication system type table, the radio communication system suitable for the radio communication terminal 10 is predicted to determine the suitability of the current radio communication system, and predicted if it is determined to be nonconforming System switching information including a wireless communication system identifier indicating the wireless communication system is notified to the wireless communication terminal 10, and the wireless communication terminal 10 is handed over. That is, the wireless communication system is predicted and handed over based on the acceleration indicating the moving state of the wireless communication terminal 10. As a result, a handover destination can be selected in consideration of changes in the communication environment due to movement of the radio communication terminal 10, communication errors that occur due to handover can be suppressed, and throughput can be improved.

  In the fourth embodiment, when it is determined that the radio communication system is compatible, the radio control server 30 includes the measurement result information notified from the radio communication terminal 10, the radio communication system identifier, and the acceleration information. Using the available bandwidth information table in which the estimated available bandwidth value is registered in association with each other, the available bandwidth of the wireless communication terminal 10 is predicted to determine the adaptability of the current available bandwidth. If the wireless communication terminal 10 determines that the wireless communication terminal 10 is incompatible, the wireless communication terminal 10 is notified of available bandwidth information including the predicted available bandwidth (predicted usable bandwidth value), and the data transmission rate of the wireless communication terminal 10 is determined. Change it. That is, based on the acceleration indicating the movement state of the wireless communication terminal 10, the available bandwidth is predicted and the data transmission rate is changed. Thereby, the communication error which generate | occur | produces by the change of the communication environment by the movement of the radio | wireless communication terminal 10 can be suppressed, and a through-put can be improved.

  In the fourth embodiment, the handover operation has been described by taking the mobile communication system of the first embodiment as an example. However, in the mobile communication systems of the second and third embodiments as well, In wireless control servers 30a and 30b, a wireless communication system type table and functions of search unit 31 and wireless determination unit 32 of the fourth embodiment (in steps S403 to S405 described with reference to the sequence diagram of FIG. 13 above) This can be realized if a processing function is provided.

  Specifically, in the mobile communication system of the second embodiment, a storage unit for storing a wireless communication system type table and a wireless communication system type table are stored in the wireless control server 30a shown in FIG. And a search unit for searching, and a function for determining the suitability of the wireless communication system may be added to the wireless determination unit 32.

  In the mobile communication system of the third embodiment, the storage unit 34 of the wireless control server 30b shown in FIG. 9 stores the wireless communication system type table, and the search unit 31a stores the wireless communication system type table. And a function for determining the suitability of the wireless communication system may be added to the wireless determination unit 32.

Embodiment 5. FIG.
A fifth embodiment of the present invention will be described with reference to FIGS. The mobile communication system according to the fifth embodiment of the present invention is substantially the same as the mobile communication system according to the first embodiment shown in FIG. The difference between the mobile communication system of the first embodiment and the mobile communication system of the fifth embodiment is an information table stored in the storage unit 34 of the radio control server 30. The storage unit 34 of the wireless control server 30 according to the fifth embodiment includes, as an information table, all the base stations 20 and 21 connected to the core network 40 in addition to the available bandwidth information table shown in FIG. A wireless usage efficiency information table in which the wireless usage efficiency information including the collected load conditions of the base stations 20 and 21 is registered is stored.

  FIG. 14 is a diagram illustrating a wireless usage efficiency information table. In FIG. 14, the wireless utilization efficiency information table includes a base station ID in which an identifier for identifying a base station given in advance to the base stations 20 and 21 is registered, and the base station ID in association with the base station ID. The collected wireless utilization efficiency is composed of wireless utilization efficiency information registered.

  Next, the operation of the mobile communication system according to the fifth embodiment will be described with reference to the sequence diagram of FIG. 15, FIGS. 1 to 4, and FIG. 14. It is assumed that the wireless communication terminal 10 is communicating with the base station 20 using the wireless I / F unit 16-1. Further, it is assumed that the wireless control server 30 updates the wireless usage efficiency information table stored in the storage unit 34 by collecting the wireless usage efficiency from the base stations 20 and 21 at predetermined intervals.

  When the predetermined measurement time is reached, the sensor information measurement unit 13 of the wireless communication terminal 10 measures the acceleration of the terminal itself (step S500). The sensor information measurement unit 13 includes the measured acceleration, a terminal identifier given to the terminal in advance, a wireless communication system identifier (in this case, W-CDMA) indicating the wireless communication system currently used by the terminal, Measurement result information including the available bandwidth and the base station identifier of the currently connected base station (in this case, the base station identifier of the base station 20) is created (step S501). The sensor information measurement unit 13 outputs the generated measurement result information to the network I / F unit 11.

  The network I / F unit 11 of the wireless communication terminal 10 generates a measurement result information frame from the measurement result information, and transmits the generated measurement result information frame via the currently used wireless I / F unit 16-1 ( Step S502). The measurement result information frame reaches the radio control server 30 via the base station 20 and the core network 40.

  When receiving the measurement result information frame, the network I / F unit 33 of the wireless control server 30 extracts the measurement result information from the received measurement result information frame, and outputs the extracted measurement result information to the search unit 31.

  The search unit 31 of the radio control server 30 searches the radio communication system type and acceleration information in the available bandwidth information table stored in the storage unit 34 using the radio communication system identifier and acceleration in the measurement result information as search keys. Then, an available bandwidth prediction value registered in the available bandwidth of the available bandwidth information table in association with the wireless communication system type and acceleration information that matches the search key is acquired (step S503).

  The search unit 31 of the radio control server 30 searches for the base station ID in the radio utilization efficiency information table stored in the storage unit 34 using the base station identifier in the measurement result information as a search key, and matches the search key. The wireless utilization efficiency registered in the wireless utilization efficiency information table in association with the base station ID is acquired (step S504). The search unit 31 outputs the acquired available bandwidth and wireless usage efficiency, and measurement result information to the wireless determination unit 32.

  The wireless determination unit 32 of the wireless control server 30 obtains an estimated usable bandwidth considering the wireless utilization efficiency based on the usable bandwidth and the wireless utilization efficiency input from the search unit 31 (step S505). The selection of the available bandwidth predicted value considering the wireless usage efficiency is performed by, for example, a predetermined calculation formula (a calculation formula in which the wireless usage efficiency is weighted with respect to the available bandwidth predicted value input from the search unit 31). Etc.).

  The wireless determination unit 32 of the wireless control server 30 determines the adaptability of the available bandwidth of the wireless communication terminal 10 based on the current available bandwidth in the measurement result information and the obtained available bandwidth prediction value ( Step S506). Specifically, the wireless determination unit 32 compares the current available bandwidth in the measurement result information with the obtained available bandwidth predicted value, and if the comparison results match, the wireless communication terminal 10 available bandwidths are determined to be compatible, and if the comparison results do not match, it is determined that the available bandwidth of the wireless communication terminal 10 is incompatible. When the determination result is incompatible, the wireless determination unit 32 generates usable bandwidth information including the obtained usable bandwidth prediction value, and outputs the generated usable bandwidth information to the network I / F unit 33. .

  The network I / F unit 33 of the wireless control server 30 generates an available bandwidth information frame from the available bandwidth information, and transmits the generated available bandwidth information frame to the core network 40 (step S507). The available bandwidth information frame reaches the wireless communication terminal 10 via the core network 40 and the base station 20.

  When the available bandwidth information frame is received via the wireless I / F unit 16-1 of the wireless communication terminal 10, the network I / F unit 11 extracts the available bandwidth information from the received available bandwidth information frame. The extracted usable bandwidth information is output to the wireless control unit 14. The wireless control unit 14 changes the data transmission rate based on the available bandwidth information from the network I / F unit 11 (step S508).

  As described above, in the fifth embodiment, the wireless communication terminal 10 measures the acceleration of its own terminal, the measured acceleration, the wireless communication system identifier for identifying the wireless communication system currently used, Measurement result information including the current available bandwidth and the base station identifier for identifying the base station to which the terminal is connected is generated and notified to the radio control server 30. The radio control server 30 includes a measurement result information notified from the radio communication terminal 10, an available bandwidth information table in which an available bandwidth prediction value is registered in association with the radio communication system identifier and acceleration information, Using the wireless interest efficiency table in which the wireless usage efficiency is registered in association with the station identifier, the available bandwidth of the wireless communication terminal 10 is predicted to determine the adaptability of the current available bandwidth, If the wireless communication terminal 10 determines that the wireless communication terminal 10 is incompatible, the wireless communication terminal 10 is notified of available bandwidth information including the predicted available bandwidth (predicted usable bandwidth value), and the data transmission rate of the wireless communication terminal 10 is changed. Let That is, based on the acceleration indicating the movement state of the wireless communication terminal 10 and the wireless utilization efficiency of the base station 20 to which the wireless communication terminal 10 is connected, the usable bandwidth is predicted to change the data transmission rate. Yes. Thereby, the communication error which generate | occur | produces by the change of the communication environment by the movement of the radio | wireless communication terminal 10 can be suppressed, and a through-put can be improved.

  Actually, there are a plurality of wireless communication terminals 10 in the mobile communication system. Therefore, after the radio control server 30 notifies the available bandwidth information to an arbitrary radio communication terminal 10, another radio communication terminal 10 newly connects to the base stations 20 and 21. There may be a case where the communication environment changes and the available bandwidth notified last time cannot be used. Therefore, the wireless determination unit 32 of the wireless control server 30 uses the same wireless communication terminal 10 as the wireless communication terminal 10 for the remaining available bandwidth notified as the available bandwidth information to the wireless communication terminal 10 that has notified the measurement result information. Allocation to other radio communication terminals 10 using the communication system, and the assigned radio available bandwidth is notified to other radio communication terminals 10 as available bandwidth information to change the data transmission rate. Good. Thereby, the communication error of all the radio | wireless communication terminals 10 can be suppressed according to the change of the communication environment in a mobile communication system, and the throughput as the whole system can be improved.

  In the fifth embodiment, the mobile communication system of the first embodiment is taken as an example to estimate the available bandwidth in consideration of the radio utilization efficiency of the base stations 20 and 21, and thereby the radio communication terminal 10 In the mobile communication systems of the second and third embodiments, the radio control servers 30a and 30b also include the radio utilization efficiency information table and the fifth embodiment. This can be realized by providing the functions of the search unit 31 and the wireless determination unit 32 (the functions of the processes in steps S504 and S505 described with reference to the sequence diagram of FIG. 15).

  Specifically, in the mobile communication system of the second embodiment, the wireless control server 30a shown in FIG. 7 includes a storage unit that stores a wireless utilization efficiency information table, and the wireless utilization efficiency information table. The bandwidth calculating unit 35 may be provided with a function of searching for the wireless bandwidth, and the wireless determination unit 32 may be added with a function of obtaining a predicted available bandwidth considering the wireless usage efficiency.

  In the mobile communication system of the third embodiment, the storage unit 34 of the wireless control server 30b shown in FIG. 9 stores the wireless use efficiency information table, and the search unit 31a stores the wireless use efficiency information table. And a function for obtaining an estimated available bandwidth considering the wireless utilization efficiency may be added to the wireless determination unit 32.

Embodiment 6 FIG.
A sixth embodiment of the present invention will be described with reference to FIGS. In the first to fifth embodiments, the data transmission rate of the wireless communication terminal in which the wireless control server exists in the mobile communication system is changed. In the sixth embodiment, the wireless communication terminal autonomously changes the data transmission rate.

  FIG. 16 is a diagram showing the configuration of the mobile communication system according to the sixth embodiment of the present invention. The mobile communication system shown in FIG. 16 includes a wireless communication terminal 10b instead of the wireless communication terminal 10 of the mobile communication system of the first embodiment shown in FIG. 1, and the wireless control server 30 is deleted. Yes. Constituent elements having the same functions as those of the mobile communication system of the first embodiment shown in FIG. 1 are given the same reference numerals, and redundant descriptions are omitted.

  FIG. 17 is a block diagram illustrating a configuration of the wireless communication terminal 10b illustrated in FIG. The wireless communication terminal 10b illustrated in FIG. 17 includes a sensor information measurement unit 13a instead of the sensor information measurement unit 13 of the wireless communication terminal 10 illustrated in FIG. 2, and further includes a storage unit 19. Components having the same functions as those of the wireless communication terminal 10 shown in FIG. 2 are given the same reference numerals, and redundant descriptions are omitted.

  The storage unit 19 stores an available bandwidth predicted value information table. The registration items of the available bandwidth predicted value information table are the same as the registration items of the available bandwidth information table shown in FIG. 4, and the wireless communication system identifier that the mobile communication system has is registered. A communication system type, acceleration information in which acceleration is registered, and an available bandwidth in which an available bandwidth prediction value that is a predicted value of a bandwidth that can be used in association with the wireless communication system type and acceleration information is registered Consists of.

  The sensor information measurement unit 13a acquires the measurement value (acceleration) of the acceleration sensor 15 via the sensor I / F unit 12, and based on the wireless communication identifier indicating the currently used wireless communication system and the acquired acceleration. The available bandwidth predicted value information table stored in the storage unit 19 is searched to obtain the available bandwidth predicted value.

  Next, the operation of the radio communication terminal 10b applied to the mobile communication system according to the sixth embodiment of the present invention will be described with reference to the flowchart of FIG. 18, FIG. 16, and FIG. It is assumed that the wireless communication terminal 10b is communicating with the base station 20 using the wireless I / F unit 16-1.

  When the predetermined measurement time is reached, the sensor information measurement unit 13a measures the acceleration of the terminal itself (step S600). Specifically, the value (acceleration) of the acceleration sensor 15 is acquired via the sensor I / F unit 12.

  The sensor information measuring unit 13a uses the wireless communication system identifier (in this case, W-CDMA) of the currently used wireless communication system and the acquired acceleration as a search key, and the wireless communication system type and acceleration information matching the search key. The available bandwidth predicted value registered in the available bandwidth predicted value information table in association with is acquired (step S601). The sensor information measurement unit 13a outputs the acquired usable bandwidth prediction value to the wireless control unit 14.

  The wireless control unit 14 determines the adaptability of the available bandwidth based on the predicted available bandwidth input from the sensor information measuring unit 13a and the current available bandwidth (step S602). Specifically, the wireless control unit 14 calculates the difference between the predicted available bandwidth input from the sensor information measuring unit 13a and the current available bandwidth. The wireless control unit 14 compares the calculated difference with a predetermined threshold value. The wireless control unit 14 determines that the available bandwidth is compatible when the calculated difference is equal to or less than the threshold, and the available bandwidth is not compatible when the calculated difference exceeds the threshold. Is determined.

  When the determination result is incompatible (step S603, Yes), the wireless control unit 14 changes the data transmission rate based on the available bandwidth prediction value input from the sensor information measurement unit 13a (step S604). Specifically, the data transmission rate is selected based on the bandwidth requested by the currently executing application, with the estimated available bandwidth input from the sensor information measurement unit 13a as the upper limit. The wireless control unit 14 notifies the currently used wireless I / F unit 16-1 of the selected data transmission rate, and the wireless I / F unit 16-1 subsequently performs the network I / F at the notified data transmission rate. The frame from the unit 11 is transmitted.

  As described above, in the sixth embodiment, the wireless communication terminal 10b measures the acceleration of its own terminal, the wireless communication system identifier indicating the wireless communication system currently used, the measured acceleration, Using the available bandwidth information table in which the estimated available bandwidth value is registered in association with the communication system identifier and the acceleration information, the available bandwidth is predicted to determine the adaptability of the current available bandwidth. If it is determined that it is nonconforming, the data transmission rate is changed based on the predicted available bandwidth. That is, the wireless communication terminal 10b changes the data transmission rate by predicting the available bandwidth based on the acceleration indicating the movement state of the terminal itself. Thereby, the communication error which generate | occur | produces by the change of the communication environment by the movement of the radio | wireless communication terminal 10b can be suppressed, and a through-put can be improved.

  In the sixth embodiment, the W-CDMA wireless communication system and the W-LAN wireless communication system have been described as examples. However, the wireless communication system is not limited to these.

  In the sixth embodiment, the wireless communication terminal 10b includes a wireless I / F unit 16-1 having a W-CDMA interface function and a wireless I / F unit having a W-LAN wireless interface function. However, the wireless communication terminal 10b only needs to have a wireless interface function of at least one wireless communication system among different wireless communication systems constituting the mobile communication system.

  In the sixth embodiment, acceleration is used. However, a moving speed obtained by integrating acceleration may be used. In this case, the sensor information measurement unit 13a may integrate the acceleration measured from the acceleration sensor 15 via the sensor I / F unit 12 to obtain the movement speed, and use the obtained movement speed instead of the acceleration. . In addition, the moving speed may be registered in the usable bandwidth predicted value information table stored in the storage unit 19 instead of the acceleration information.

Embodiment 7 FIG.
A seventh embodiment of the present invention will be described with reference to FIG. The mobile communication system according to the seventh embodiment uses the wireless communication according to the second embodiment shown in FIG. 6 instead of the wireless communication terminal 10b of the mobile communication system according to the sixth embodiment shown in FIG. A communication terminal 10a is provided.

  In the mobile communication system according to the seventh embodiment, there is no radio control server. Therefore, the sensor information measurement unit 13 of the wireless communication terminal 10 a outputs the created measurement result information to the movement speed calculation unit 18.

  The moving speed calculation unit 18 calculates a future available bandwidth from the moving speed at the current measurement time in the measurement result information and the acceleration at the current measurement time, using the previous equations (1) and (2).

  Next, with reference to the flowchart of FIG. 19 and FIGS. 6 and 16, the operation of the radio communication terminal 10a applied to the mobile communication system according to the seventh embodiment of the present invention will be described. It is assumed that the wireless communication terminal 10a communicates by connecting to the base station 20 using the wireless I / F unit 16-1.

  When the predetermined measurement time is reached, the sensor information measurement unit 13 measures the acceleration of the terminal itself (step S700). The sensor information measurement unit 13 outputs the measured acceleration to the movement speed calculation unit 18.

  The movement speed calculation unit 18 integrates the acceleration input from the sensor information measurement unit 13 and calculates the movement speed of the terminal itself (step S701). The movement speed calculation unit 18 outputs the calculated movement speed to the sensor information measurement unit 13.

  The sensor information measurement unit 13 reads the current available bandwidth from the bandwidth information storage unit 17. The sensor information measuring unit 13 is a wireless communication indicating the moving speed (moving speed at the current measurement time) input from the moving speed calculating unit 18, the acceleration at the measured current measurement time, and the wireless communication system currently used by the terminal itself. Measurement result information including the system identifier (in this case, W-CDMA) and the current available bandwidth read from the bandwidth information storage unit 17 is created. The sensor information measurement unit 13 outputs the generated measurement result information to the movement speed calculation unit 18.

  The moving speed calculation unit 18 uses the moving speed at the current measurement time, the acceleration at the current measurement time, and the current available bandwidth in the measurement result information to calculate future movements according to the previous equations (1) and (2). An available bandwidth is calculated (step S702). The moving speed calculation unit 18 outputs the calculated future available bandwidth and measurement result information to the wireless control unit 14.

  The radio control unit 14 determines the adaptability of the available bandwidth of the terminal itself based on the current available bandwidth in the measurement result information and the future available bandwidth calculated by the moving speed calculation unit 18 (step S703). Specifically, the wireless control unit 14 calculates the difference between the future available bandwidth input from the moving speed calculation unit 18 and the current available bandwidth in the measurement result information. The wireless control unit 14 compares the calculated difference with a predetermined threshold value. The wireless control unit 14 determines that the available bandwidth is compatible when the calculated difference is equal to or less than the threshold, and the available bandwidth is not compatible when the calculated difference exceeds the threshold. Is determined.

  If the determination result is incompatible (step S704, Yes), the wireless control unit 14 changes the data transmission rate based on the available bandwidth input from the sensor information measurement unit 13 (step S705).

  As described above, in the seventh embodiment, the wireless communication terminal 10a measures the acceleration of its own terminal, the measured acceleration, the moving speed obtained by integrating this acceleration, and the current available bandwidth. The bandwidth is used to predict the available bandwidth according to the calculation formula to determine the suitability of the current available bandwidth, and if it is determined that the bandwidth is not suitable, the data transmission rate based on the predicted available bandwidth To change. In other words, the wireless communication terminal 10a changes the data transmission rate by predicting the available bandwidth based on the acceleration indicating the movement state of the terminal itself. Thereby, the communication error which generate | occur | produces by the change of the communication environment by movement of the radio | wireless communication terminal 10a can be suppressed, and a through-put can be improved.

Embodiment 8 FIG.
An eighth embodiment of the present invention will be described with reference to FIG. In the previous sixth and seventh embodiments, the change of the data transmission rate in the same wireless communication system has been described. In the eighth embodiment, switching between wireless communication systems, that is, handover to a different wireless communication system will be described.

  The mobile communication system according to the eighth embodiment of the present invention is substantially the same as the mobile communication system according to the sixth embodiment shown in FIG. The difference between the mobile communication system of the sixth embodiment and the mobile communication system of the eighth embodiment is an information table stored in the storage unit 19 of the radio communication terminal 10b. The storage unit 19 of the wireless communication terminal 10b according to the eighth embodiment is necessary for determining whether or not to perform a handover in addition to the usable bandwidth predicted value information table described in the previous sixth embodiment as an information table. A wireless communication system type table is stored. Since the wireless communication system type table is the same as the wireless communication system type table stored in the storage unit 34 of the wireless control server 30 of the fourth embodiment shown in FIG. 12, the description thereof is omitted here.

  Next, with reference to the flowchart of FIG. 20, FIG. 12, and FIG. 17, the operation of handover of the radio communication terminal 10b applied to the mobile communication system of the eighth embodiment will be described. It is assumed that the wireless communication terminal 10b is communicating with the base station 20 using the wireless I / F unit 16-1.

  When the predetermined measurement time is reached, the sensor information measurement unit 13a measures the acceleration of the terminal itself (step S800). The sensor information measuring unit 13a searches the current wireless communication system type and acceleration information in the wireless communication system type table stored in the storage unit 19 using the currently used wireless communication system and the measured acceleration as a search key. Then, the wireless communication system registered in the adaptive wireless communication system type in the wireless communication system type table is acquired in association with the current wireless communication system type and acceleration information matching the search key (step S801). The sensor information measuring unit 13a outputs the acquired wireless communication system to the wireless control unit 14.

  The wireless control unit 14 determines the adaptability of the wireless communication system currently used by the terminal itself based on the currently used wireless communication system and the wireless communication system input from the sensor information measuring unit 13a (step S1). S802). Specifically, the wireless control unit 14 compares the currently used wireless communication system with the wireless communication system input from the sensor information measuring unit 13a, and if the comparison results match, the wireless control unit 14 It is determined that the communication system is compatible, and if the comparison results do not match, it is determined that the wireless communication system is not compatible.

  If the determination result is incompatible (step S803, Yes), the wireless control unit 14 changes the wireless communication system to be used based on the wireless communication system input from the sensor information measurement unit 13a (step S804). Specifically, since the wireless communication terminal 10b is currently using a W-CDMA wireless communication system, the wireless communication system input from the sensor information measuring unit 13a is a W-LAN wireless communication system. . Therefore, the radio control unit 14 executes a general handover process for switching the connection from the base station 20 of the radio communication system using the W-CDMA system to the base station 21 of the radio communication system using the W-LAN system.

  On the other hand, if the determination result is appropriate (step S803, No), the wireless control unit 14 outputs an instruction for requesting the available bandwidth to the sensor information measurement unit 13a, and refers to the flowchart of FIG. The processing shifts to the data transmission rate change processing described above (step S805). In addition, since the sensor information measurement unit 13a measures the acceleration in step S800, the process of steps S601 to S604 of the data transmission rate change process may be executed.

  As described above, in the eighth embodiment, the radio communication terminal 10b measures the acceleration of its own terminal, and the radio communication system identifier indicating the currently used radio communication system, the measured acceleration, Wireless communication as a destination using a wireless communication system identifier indicating a current wireless communication system and a wireless communication system type table in which a wireless communication system identifier indicating a wireless communication system adapted to be associated with acceleration information is registered The degree of compatibility of the system is determined, and handover is executed when it is determined that the system is not compatible. That is, the wireless communication system to be a handover destination is selected based on the acceleration indicating the moving state of the wireless communication terminal 10b. Thereby, it is possible to select a handover destination in consideration of a change in the communication environment due to movement of the radio communication terminal 10b, it is possible to suppress a communication error caused by the handover, and improve throughput.

  In the eighth embodiment, the wireless communication terminal 10b according to the sixth embodiment has been described as an example. However, the wireless communication terminal type table of the wireless communication terminal 10a according to the seventh embodiment also includes a wireless communication terminal type table. If a storage unit for storing and a search unit for searching the wireless communication system type table are provided and a function for determining the suitability of the wireless communication system is added to the wireless control unit 14, a handover is performed in the same manner as the wireless communication terminal 10b. It is possible.

  In the eighth embodiment, the acceleration is used. However, a moving speed obtained by integrating the acceleration may be used. In this case, the sensor information measurement unit 13a may integrate the acceleration measured from the acceleration sensor 15 via the sensor I / F unit 12 to obtain the movement speed, and use the obtained movement speed instead of the acceleration. . Further, the moving speed may be registered in the wireless communication system type information table stored in the storage unit 19 instead of the acceleration information.

  As described above, the mobile communication system according to the present invention is useful for suppressing communication errors caused by environmental changes due to movement of radio communication terminals, and particularly for suppressing communication errors of radio communication terminals moving at high speed. Is suitable.

It is a figure which shows the structure of the mobile communication system of Embodiment 1 in this invention. It is a block diagram which shows the structure of the radio | wireless communication terminal shown in FIG. It is a block diagram which shows the structure of the radio | wireless control server shown in FIG. It is a figure which shows the structure of the available bandwidth information table which the memory | storage part of the radio | wireless control server shown in FIG. 3 memorize | stores. It is a sequence diagram for demonstrating operation | movement of Embodiment 1 of the mobile communication system in this invention. It is a block diagram which shows the structure of the radio | wireless communication terminal applied to the mobile communication system of Embodiment 2 in this invention. It is a block diagram which shows the structure of the radio | wireless control server applied to the mobile communication system of Embodiment 2 in this invention. It is a sequence diagram for demonstrating operation | movement of Embodiment 2 of the mobile communication system in this invention. It is a block diagram which shows the structure of the radio | wireless control server applied to the mobile communication system of Embodiment 3 in this invention. It is a figure which shows the structure of the radio | wireless communication terminal information table which the memory | storage part of the radio control server shown in FIG. 9 memorize | stores. It is a sequence diagram for demonstrating operation | movement of Embodiment 3 of the mobile communication system in this invention. It is a figure which shows the structure of the radio | wireless communications system classification table which the memory | storage part of the radio | wireless control server applied to the mobile communication system of Embodiment 4 in this invention memorize | stores. It is a sequence diagram for demonstrating operation | movement of Embodiment 4 of the mobile communication system in this invention. It is a figure which shows the structure of the radio | wireless utilization efficiency information table which the memory | storage part of the radio | wireless control server applied to the mobile communication system of Embodiment 5 in this invention memorize | stores. It is a sequence diagram for demonstrating operation | movement of Embodiment 5 of the mobile communication system in this invention. It is a figure which shows the structure of the mobile communication system of Embodiment 6 in this invention. It is a block diagram which shows the structure of the radio | wireless communication terminal shown in FIG. It is a flowchart for demonstrating operation | movement of Embodiment 6 of the radio | wireless communication terminal applied to the mobile communication system in this invention. It is a flowchart for demonstrating operation | movement of Embodiment 7 of the radio | wireless communication terminal applied to the mobile communication system in this invention. It is a flowchart for demonstrating operation | movement of Embodiment 8 of the radio | wireless communication terminal applied to the mobile communication system in this invention.

Explanation of symbols

10, 10a, 10b Wireless communication terminal 11, 33 Network I / F unit 12 Sensor I / F unit 13, 13a Sensor information measuring unit 14 Wireless control unit 15 Acceleration sensor 16-1, 16-2 Wireless I / F unit 17 Band Width information storage unit 18 Movement speed calculation unit 19, 34 Storage unit 20, 21 Base station 22, 23 Communication area 30, 30a, 30b Radio control server 31, 31a Search unit 32 Radio determination unit 35 Bandwidth calculation unit 40 Core network

Claims (20)

In a mobile communication system comprising: a wireless control server capable of communicating with a plurality of different wireless communication systems; and a wireless communication terminal capable of communicating with at least one of the plurality of different wireless communication systems.
The wireless communication terminal is
Measures the movement state of the own terminal, the movement state information obtained from the measured movement state, the wireless communication system identifier for identifying the wireless communication system used by the own terminal, and the available bandwidth of the own terminal A moving state measuring unit that generates measurement result information including and notifies the wireless control server;
A radio control unit that changes a data transmission rate to a radio communication system in use based on an available bandwidth prediction value included in the available bandwidth information notified from the radio control server;
With
The wireless control server
An available bandwidth prediction value information table in which an available bandwidth prediction value is registered in association with a wireless communication system identifier and movement state information for identifying the different wireless communication system;
A search unit for acquiring an available bandwidth predicted value corresponding to a wireless communication system identifier and movement state information included in measurement result information notified from the wireless communication terminal from the available bandwidth predicted value information table;
When the available bandwidth prediction value acquired by the search unit matches the available bandwidth in the measurement result information notified from the wireless communication terminal, the available bandwidth of the wireless communication terminal is If the available bandwidth acquired by the search unit and the current available bandwidth in the measurement result information notified from the wireless communication terminal do not match, the wireless communication terminal If the available bandwidth is determined to be incompatible, and if it is determined to be incompatible, the available bandwidth information including the estimated available bandwidth acquired by the search unit is notified to the wireless communication terminal A wireless determination unit to perform,
A mobile communication system comprising: In a mobile communication system comprising: a wireless control server capable of communicating with a plurality of different wireless communication systems; and a wireless communication terminal capable of communicating with at least one of the plurality of different wireless communication systems.
The wireless communication terminal is
A moving state measuring unit that measures a moving state of the own terminal, generates moving state information obtained from the measured moving state, and measurement result information including an available bandwidth of the own terminal, and notifies the radio control server; ,
On the basis of the accessible capacity bandwidth prediction value included in the available bandwidth information notified from the radio control server, and a wireless control unit for changing the data transmission rate of the wireless communication system in use,
With
The wireless control server
A bandwidth calculation unit that calculates an estimated available bandwidth using the measurement result information notified from the wireless communication terminal;
When the predicted available bandwidth calculated by the bandwidth calculator matches the available bandwidth in the measurement result information notified from the wireless communication terminal, the available bandwidth of the wireless communication terminal When it is determined that the bandwidth is suitable, and the available bandwidth predicted value calculated by the bandwidth calculation unit and the available bandwidth in the measurement result information notified from the wireless communication terminal do not match, When it is determined that the available bandwidth of the wireless communication terminal is incompatible and it is determined to be incompatible, the available bandwidth information including the estimated available bandwidth calculated by the bandwidth calculation unit is A wireless determination unit for notifying the wireless communication terminal;
A mobile communication system comprising: In a mobile communication system comprising: a wireless control server capable of communicating with a plurality of different wireless communication systems; and a wireless communication terminal capable of communicating with at least one of the plurality of different wireless communication systems.
The wireless communication terminal is
Movement state measurement that measures the movement state of the own terminal, generates movement result information including the movement state information obtained from the measured movement state, and a terminal identifier for identifying the own terminal, and notifies the radio control server of the measurement result information And
A wireless control unit that changes a data transmission rate to a wireless communication system in use, based on an estimated available bandwidth value included in available bandwidth information notified from the wireless control server;
With
The wireless control server
A wireless communication terminal information table in which the available bandwidth of the wireless communication terminal indicated by the terminal identifier is registered in association with the terminal identifier;
A search unit for acquiring an available bandwidth corresponding to a terminal identifier included in measurement result information notified from the wireless communication terminal from the wireless communication terminal information table;
A bandwidth calculation unit that calculates an available bandwidth prediction value using the available bandwidth acquired by the search unit and the movement state information included in the measurement result information notified from the wireless communication terminal;
When the estimated available bandwidth calculated by the bandwidth calculator matches the available bandwidth acquired by the search unit, the available bandwidth of the wireless communication terminal is matched. If the available bandwidth predicted value calculated by the bandwidth calculation unit and the available bandwidth acquired by the search unit do not match, the available bandwidth of the wireless communication terminal is incompatible When it is determined that it is non-conforming, the wireless communication terminal is notified of available bandwidth information including the predicted available bandwidth calculated by the bandwidth calculation unit, and the wireless communication terminal information table A wireless determination unit that changes the available bandwidth to the predicted available bandwidth notified to the wireless communication terminal;
A mobile communication system comprising: In a mobile communication system comprising a radio control server capable of communicating with a plurality of different radio communication systems, and a radio communication terminal capable of communicating with at least two of the plurality of different radio communication systems,
The wireless communication terminal is
Measure the movement state of the terminal itself, and generate measurement result information including the movement state information obtained from the measured movement state and the wireless communication system identifier for identifying the wireless communication system used by the terminal. A moving state measuring unit for notifying the radio control server;
A wireless control unit for changing a wireless communication system to be used from a wireless communication system currently in use to a wireless communication system indicated by a wireless communication system identifier in system switching information notified from the wireless control server;
With
The wireless control server
A wireless communication system type information table in which a wireless communication system identifier indicating a wireless communication system to be moved is registered in association with a wireless communication system identifier and movement state information for identifying the different wireless communication system;
A wireless communication system identifier indicating a wireless communication system serving as a movement destination corresponding to a wireless communication system identifier and movement state information included in measurement result information notified from the wireless communication terminal is acquired from the wireless communication system type information table. A search section;
If the wireless communication system identifier acquired by the search unit matches the wireless communication system identifier in the measurement result information notified from the wireless communication terminal, the wireless communication system of the wireless communication terminal is compatible. If the wireless communication system identifier acquired by the search unit and the wireless communication system identifier in the measurement result information notified from the wireless communication terminal do not match, the wireless communication system of the wireless communication terminal If it is determined that it is non-conforming and if it is determined that it is non-conforming, a wireless determination unit that notifies the wireless communication terminal of system switching information including the wireless communication system identifier acquired by the search unit;
A mobile communication system comprising: The movement state measuring unit of the wireless communication terminal is
The mobile communication system according to any one of claims 1 to 4, wherein measurement result information is transmitted to the radio control server at predetermined intervals. The movement state measuring unit of the wireless communication terminal is
The mobile communication system according to any one of claims 1 to 4, wherein measurement result information is transmitted to the radio control server when the measured movement state exceeds a predetermined threshold value. The movement state measuring unit of the wireless communication terminal is
Transmitting measurement result information including a base station identifier indicating a base station of a wireless communication system currently in use to the radio control server;
The wireless control server
A wireless utilization efficiency information table in which the wireless utilization efficiency of the base station indicated by the base station identifier is registered in association with a base station identifier for identifying each base station of the wireless communication system;
Further comprising
The search unit or bandwidth calculation unit of the radio control server is
Obtaining the wireless usage efficiency corresponding to the base station identifier in the measurement result information notified from the wireless communication terminal,
The wireless determination unit of the wireless control server is
Notification from the wireless communication terminal of an available bandwidth obtained from the wireless utilization efficiency acquired by the search unit or the bandwidth calculation unit and an estimated available bandwidth value from the search unit or the bandwidth calculation unit Determining the adaptability of the available bandwidth of the wireless communication terminal using the available bandwidth in the measurement result information to be
The mobile communication system according to any one of claims 1 to 6. The wireless determination unit of the wireless control server is
After notifying the available bandwidth information to the wireless communication terminal that has transmitted the measurement result information, new available bandwidth information is sent to another wireless communication terminal using the same base station as the wireless communication terminal. The mobile communication system according to claim 7, wherein notification is performed.   The movement state measured by the movement state measurement unit is an acceleration, and the movement state information is a movement speed obtained by integrating the measured acceleration and / or the measured acceleration. The mobile communication system according to any one of the above. Applied to a mobile communication system comprising a wireless communication terminal capable of communicating with at least one of a plurality of different wireless communication systems and measuring its own mobile state, and obtained from the mobile state transmitted from the wireless communication terminal Movement state information, a wireless communication system identifier for identifying a wireless communication system used by the wireless communication terminal, an available bandwidth of the wireless communication terminal, a terminal identifier for identifying the wireless communication terminal, and A wireless control server for controlling a data transmission rate of the wireless communication terminal based on measurement result information including a base station identifier for identifying a base station used by the wireless communication terminal;
An available bandwidth prediction value information table in which an available bandwidth prediction value is registered in association with a wireless communication system identifier and movement state information for identifying the different wireless communication system;
A search unit for acquiring an available bandwidth predicted value corresponding to a wireless communication system identifier and movement state information included in measurement result information notified from the wireless communication terminal from the available bandwidth predicted value information table;
When the available bandwidth prediction value acquired by the search unit matches the available bandwidth in the measurement result information notified from the wireless communication terminal, the available bandwidth of the wireless communication terminal is If the available bandwidth acquired by the search unit and the current available bandwidth in the measurement result information notified from the wireless communication terminal do not match, the wireless communication terminal If the available bandwidth is determined to be incompatible, and if it is determined to be incompatible, the available bandwidth information including the estimated available bandwidth acquired by the search unit is notified to the wireless communication terminal A wireless determination unit to perform,
A wireless control server comprising: Applied to a mobile communication system comprising a wireless communication terminal capable of communicating with at least one of a plurality of different wireless communication systems and measuring its own mobile state, and obtained from the mobile state transmitted from the wireless communication terminal Mobile state information, a wireless communication system identifier for identifying a wireless communication system used by the wireless communication terminal, an available bandwidth of the wireless communication terminal, and a base station used by the wireless communication terminal A wireless control server for controlling a data transmission rate of the wireless communication terminal based on measurement result information including a base station identifier for identification;
A bandwidth calculation unit that calculates an estimated available bandwidth using the measurement result information notified from the wireless communication terminal;
When the predicted available bandwidth calculated by the bandwidth calculator matches the available bandwidth in the measurement result information notified from the wireless communication terminal, the available bandwidth of the wireless communication terminal When it is determined that the bandwidth is suitable, and the available bandwidth predicted value calculated by the bandwidth calculation unit and the available bandwidth in the measurement result information notified from the wireless communication terminal do not match, When it is determined that the available bandwidth of the wireless communication terminal is incompatible and it is determined to be incompatible, the available bandwidth information including the estimated available bandwidth calculated by the bandwidth calculation unit is A wireless determination unit for notifying the wireless communication terminal;
A wireless control server comprising: Applied to a mobile communication system comprising a wireless communication terminal capable of communicating with at least one of a plurality of different wireless communication systems and measuring its own mobile state, and obtained from the mobile state transmitted from the wireless communication terminal The wireless communication terminal based on the measurement result information including the mobile state information, the base station identifier for identifying the base station used by the wireless communication terminal, and the terminal identifier for identifying the wireless communication terminal A wireless control server for controlling the data transmission rate of
A wireless communication terminal information table in which the available bandwidth of the wireless communication terminal indicated by the terminal identifier is registered in association with the terminal identifier;
A search unit for acquiring an available bandwidth corresponding to a terminal identifier included in measurement result information notified from the wireless communication terminal from the wireless communication terminal information table;
A bandwidth calculation unit that calculates an available bandwidth prediction value using the available bandwidth acquired by the search unit and the movement state information included in the measurement result information notified from the wireless communication terminal;
When the estimated available bandwidth calculated by the bandwidth calculator matches the available bandwidth acquired by the search unit, the available bandwidth of the wireless communication terminal is matched. If the available bandwidth predicted value calculated by the bandwidth calculation unit and the available bandwidth acquired by the search unit do not match, the available bandwidth of the wireless communication terminal is incompatible When it is determined that it is non-conforming, the wireless communication terminal is notified of available bandwidth information including the predicted available bandwidth calculated by the bandwidth calculation unit, and the wireless communication terminal information table A wireless determination unit that changes the available bandwidth to the predicted available bandwidth notified to the wireless communication terminal;
A wireless control server comprising: Applied to a mobile communication system comprising a wireless communication terminal capable of communicating with at least one of a plurality of different wireless communication systems and measuring its own mobile state, and obtained from the mobile state transmitted from the wireless communication terminal A wireless control server for controlling handover of the wireless communication terminal based on measurement result information including a movement state information and a wireless communication system identifier for identifying a wireless communication system used by the wireless communication terminal. ,
A wireless communication system type information table in which a wireless communication system identifier indicating a wireless communication system to be moved is registered in association with a wireless communication system identifier and movement state information for identifying the different wireless communication system;
A wireless communication system identifier indicating a wireless communication system to be a movement destination corresponding to a wireless communication system identifier and movement state information included in measurement result information notified from the wireless communication terminal is acquired from the wireless communication system type information table. A search section;
If the wireless communication system identifier acquired by the search unit matches the wireless communication system identifier in the measurement result information notified from the wireless communication terminal, the wireless communication system of the wireless communication terminal is compatible. If the wireless communication system identifier acquired by the search unit and the wireless communication system identifier in the measurement result information notified from the wireless communication terminal do not match, the wireless communication system of the wireless communication terminal If it is determined that it is non-conforming and if it is determined that it is non-conforming, a wireless determination unit that notifies the wireless communication terminal of system switching information including the wireless communication system identifier acquired by the search unit;
A wireless control server comprising: A wireless utilization efficiency information table in which the wireless utilization efficiency of the base station indicated by the base station identifier is registered in association with a base station identifier for identifying each base station of the wireless communication system;
Further comprising
The search unit or bandwidth calculation unit of the radio control server is
Obtaining the wireless usage efficiency corresponding to the base station identifier in the measurement result information notified from the wireless communication terminal,
The wireless determination unit of the wireless control server is
The wireless communication terminal is notified of the available bandwidth obtained from the wireless usage efficiency acquired by the search unit or the bandwidth calculation unit and the available bandwidth from the search unit or the bandwidth calculation unit. Determining the adaptability of the available bandwidth of the wireless communication terminal using the available bandwidth in the measurement result information;
The wireless control server according to any one of claims 10 to 13. The wireless determination unit is
After notifying the available bandwidth information to the wireless communication terminal that has transmitted the measurement result information, new available bandwidth information is sent to another wireless communication terminal using the same base station as the wireless communication terminal. The wireless control server according to claim 14, wherein notification is performed. A wireless communication terminal that is applied to a mobile communication system having a plurality of different wireless communication systems and can communicate with at least one of the plurality of different wireless communication systems,
An available bandwidth prediction value information table in which an available bandwidth that is a predicted value of an available bandwidth associated with a wireless communication system identifier and movement state information for identifying the different wireless communication system is registered;
While measuring the movement state of the terminal itself, a wireless communication system identifier indicating a wireless communication system currently in use and an estimated usable bandwidth corresponding to movement state information obtained from the measured movement state are used as the usable bandwidth. A movement state measurement unit acquired from the width predicted value information table;
When determining whether or not the current available bandwidth is based on the available bandwidth and the current available bandwidth acquired by the movement state measurement unit, A wireless control unit that changes a data transmission rate to a wireless communication system that is used based on the estimated available bandwidth acquired by the moving state measurement unit;
A wireless communication terminal comprising: A wireless communication terminal that is applied to a mobile communication system having a plurality of different wireless communication systems and can communicate with at least one of the plurality of different wireless communication systems,
A moving state measuring unit for measuring the moving state of the terminal itself;
A calculation unit that calculates a predicted available bandwidth using the movement state information obtained from the movement state and the available bandwidth of the terminal itself;
Based on the estimated available bandwidth calculated by the calculation unit and the current available bandwidth, it is determined whether or not the current available bandwidth is compatible. A wireless control unit that changes a data transmission rate to a wireless communication system that is being used based on the estimated available bandwidth calculated by the calculation unit;
A wireless communication terminal comprising: The wireless control unit
Determining that the current available bandwidth is incompatible when the difference between the available bandwidth acquired by the movement state measuring unit and the current available bandwidth exceeds a predetermined threshold;
The wireless communication terminal according to claim 16 or 17, characterized by the above. A wireless communication terminal that is applied to a mobile communication system having a plurality of different wireless communication systems and can communicate with at least one of the plurality of different wireless communication systems,
A wireless communication system type information table in which a wireless communication system identifier indicating a wireless communication system to be moved is registered in association with a wireless communication system identifier and movement state information for identifying the different wireless communication system;
Radio communication that measures the movement state of the terminal itself, and that indicates a wireless communication system that is a movement destination corresponding to the wireless communication system identifier indicating the currently used wireless communication system and the movement state information obtained from the measured movement state A moving state measuring unit for acquiring a system identifier from the wireless communication system type information table;
If the wireless communication system identifier acquired by the movement state measurement unit matches the wireless communication identifier indicating the wireless communication system currently in use, it is determined that the wireless communication system is compatible, and the movement When the wireless communication system identifier acquired by the state measurement unit and the wireless communication identifier indicating the currently used wireless communication system do not match, the wireless communication system is determined to be incompatible, and it is determined to be incompatible A radio control unit that changes a radio communication system to be used for the radio communication system indicated by the radio communication system identifier acquired by the moving state measurement unit from the currently used radio communication system;
A wireless communication terminal comprising:   20. The movement state measured by the movement state measurement unit is acceleration, and the movement state information is a movement speed obtained by integrating the measured acceleration and / or the measured acceleration. The wireless communication terminal according to any one of the above.

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