JP5299382B2 - Wireless communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication system which can quickly respond to a change of point where handover should be executed while avoiding unnecessary handover. <P>SOLUTION: An in-vehicle terminal device 10 starts execution of handover if it has determined a prescribed execution condition of handover is met, and after this handover was completed, transmits handover execution completion location information and identification information of a serving base station SB before the handover to a serving base station SB after the handover. In addition, a communication base station 20 determines a recommendation location of handover execution completion based on terminal device location information, a handover map, and an expected travel route of the in-vehicle terminal device 10, transmits this information of recommendation location of handover execution completion and identification information of a target base station TB, to the in-vehicle terminal device 10, and updates the handover map based on the handover execution completion location information. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a radio communication system that includes a terminal mounted on a mobile body such as a vehicle and a plurality of communication base stations, and performs a handover from a serving base station to a target base station.

  Conventionally, as this type of wireless communication system, a wireless communication system that performs a handover based on an instantaneous value of a reception level (specifically, electric field strength) of a radio wave received from a communication base station is known. This wireless communication system will be described with reference to FIGS.

  FIG. 14 is a diagram illustrating a situation in which the vehicle C equipped with the in-vehicle terminal moves along the route R, and FIG. 15 illustrates a communication base in which the vehicle C (that is, the in-vehicle terminal) is nearby in this situation. It is a figure which shows transition of the reception level (specifically electric field strength) of the electromagnetic wave received from station B1, and transition of the reception level of the electromagnetic wave which a vehicle-mounted terminal receives from communication base station B2 far away.

  FIG. 14 shows that the separation distance between the in-vehicle terminal and the communication base station B1 is shorter than the separation distance between the communication base station B2 but the in-vehicle terminal and the communication base station B1 when the vehicle C moves along the route R. The situation where the building Sh intervenes as a shielding object is shown. For this reason, the reception level of radio waves received by the in-vehicle terminal from the communication base station B1 changes while greatly fluctuating. Specifically, as shown in FIG. 15, the reception level of the radio wave received by the in-vehicle terminal from the communication base station B1 is from the time t10 when the building Sh is not interposed between the in-vehicle terminal and the communication base station B1. It changes in a high state until time t11 when Sh begins to intervene. However, the reception level of the radio wave received by the in-vehicle terminal from the communication base station B1 starts to rapidly decrease from the time t11 when the building Sh begins to be interposed between the in-vehicle terminal and the communication base station B1, and at the time t12. Below the reception level of the radio wave received from the communication base station B2. The reception level of the radio wave received by the in-vehicle terminal from the communication base station B1 begins to recover at time t13, exceeds the reception level of the radio wave received from the communication base station B2 at time t14, and the in-vehicle terminal and the communication base station The transition starts again at a high state at time t15 when the building Sh no longer exists between B1 and B1. Thus, the reception level of the radio wave received from the communication base station B1 has a temporary drop due to the building Sh. On the other hand, as shown in FIG. 14, the distance between the in-vehicle terminal and the communication base station B <b> 2 is long, but when the vehicle C moves along the route R, a shielding object such as a building is not interposed. Therefore, although the reception level of the radio wave received by the in-vehicle terminal from the communication base station B2 is low, it changes stably.

  In the above situation, handover is executed as follows in the conventional wireless communication system.

  Specifically, in the conventional wireless communication system, first, from time t10 to time t12, the reception level of the radio wave received from the communication base station B1 is higher than the reception level of the radio wave received from the communication base station B2. Wireless communication is performed between the communication base station B1 and the in-vehicle terminal using B1 as a serving base station, and the reception level of the radio wave received by the in-vehicle terminal from the communication base station B1 is the radio wave received from the communication base station B2. At time t12 when the reception level falls below, a handover for switching the serving base station to the communication base station B2 is executed. In the conventional wireless communication system, at time t14 when the reception level of the radio wave received from the communication base station B1 exceeds the reception level of the radio wave received from the communication base station B2, handover is performed to switch the serving base station to the communication base station B1. After this time t14, wireless communication is performed between the communication base station B1 and the in-vehicle terminal using the communication base station B1 as a serving base station.

  As described above, in the conventional wireless communication system, since the handover is executed based on the instantaneous value of the reception level of the radio wave received from the communication base station, the serving base station frequently performs communication between the communication base station B1 and the communication base station B2. A so-called ping-pong phenomenon may occur.

  Although not shown in FIG. 15, a communication base that continuously exceeds both the reception level of the radio wave received from the communication base station B2 and the reception level of the radio wave received from the communication base station B1 after the time t12. Assume an example in which station B3 exists.

  In such an assumption example, the conventional wireless communication system performs a handover as follows. Specifically, in the conventional wireless communication system, first, at time t12, a handover is performed from the communication base station B1 to the communication base station B2, and shortly thereafter, a handover is performed from the communication base station B2 to the communication base station B3. Wireless communication is performed between the communication base station B3 and the in-vehicle terminal using the communication base station B3 as a serving base station.

  If a handover is performed to the communication base station B2 and a handover is performed to the communication base station B3 shortly thereafter, a direct handover may be performed from the communication base station B1 to the communication base station B3. In the wireless communication system, unnecessary handover is executed.

  As described above, in the conventional wireless communication system, since the handover is executed based on the instantaneous value of the reception level of the radio wave received from the communication base station, an unnecessary handover may occur.

  When handover is executed, a momentary interruption occurs in wireless communication between the in-vehicle terminal and the communication base station, and wireless communication becomes unstable for a certain period of time, resulting in a decrease in throughput. That is not desirable.

  For such a problem, a technique described in Patent Document 1 is known. In the technique described in Patent Document 1, a mobile communication terminal (corresponding to an in-vehicle terminal) is disconnected from a cell of a radio base station (corresponding to a communication base station) and the radio communication system is different from other radio base stations. A handover point (hereinafter also referred to as point H) that allows good communication is determined by the signal reception quality at the time of setting the radio base station, and stored as map information in the map information storage unit. Then, the radio communication system monitors the position of the mobile communication terminal, and when the mobile communication terminal reaches the point H, instructs the mobile communication terminal to perform handover and executes the handover.

JP 2004-228881 A

  According to the technique described in Patent Document 1, even if there is a temporary drop in the reception level of the radio wave received from the radio base station, handover is not performed unless the point is H. Therefore, the ping-pong phenomenon or unnecessary handover is not performed. Occurrence can be reduced.

  However, in the technique described in Patent Document 1, the point H is determined by the signal reception quality when the radio base station is set. Therefore, for example, a building or the like is built after the H point is determined, and even if the H point has actually shifted, if the mobile communication terminal reaches the shifted (before being updated) H point, A handover is executed. Thus, there is still room for improvement in the prior art described in Patent Document 1.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wireless communication system capable of quickly responding to a change in a point where handover should be performed while avoiding unnecessary handover. There is to do.

  In order to achieve such an object, the invention described in claim 1 includes a terminal, a plurality of communication base stations, and a handover map server, and performs wireless communication with the terminal among the plurality of communication base stations. Next, a serving base station that is a communication base station to perform is wirelessly communicated with a terminal from among adjacent base stations that are communication base stations located around the serving base station among a plurality of communication base stations. A wireless communication system that performs handover to switch to a target base station that is a communication base station, wherein the handover map server includes information on communication base station position information that is position information of a plurality of communication base stations and positions at which handover has been completed. A handover map server side storage device that stores a handover map in which handover execution completion position information, which is information, is stored, a communication base station, Between the serving base station and the terminal location information obtaining means for obtaining the location information of the terminal, which is information on the location of the terminal. The terminal side communication device that receives radio waves transmitted from adjacent base stations while performing wireless communication with the terminal, and the terminal location information acquired by the terminal location information acquisition means is transmitted to the serving base station by the terminal side communication device In addition, based on the terminal position information acquired by the terminal position information acquisition means, the handover execution completion recommended position information received by the terminal side communication apparatus, and the reception level of the radio wave received by the terminal side communication apparatus When it is determined whether or not a predetermined handover execution condition is satisfied, and when it is determined that the handover execution condition is satisfied, the terminal side communication device Based on the received identification information of the target base station, the execution of the handover is started, and after the completion of the execution of the handover, the handover execution completion position information which is the information of the position where the handover has been completed and the execution of the handover are started. A terminal-side control device that transmits the identification information of the previous serving base station to the serving base station after the completion of the handover by the terminal-side communication device, and the communication base station communicates with the terminal Based on the base station side communication device capable of wireless communication between the base station, the terminal location information received by the base station side communication device, the handover map stored in the handover map server, and the predicted travel route of the terminal The recommended handover execution completion position, which is the recommended position for completion of the execution, is determined. The handover execution completion position received by the base station side communication device is transmitted to the terminal by the base station side communication device, and the handover execution completion recommended position information and the target base station identification information, which is information on the recommended handover completion completion location. The base station side control device updates the handover map stored in the handover map server based on the information.

  In the above configuration as a wireless communication system, when determining whether or not a predetermined handover execution condition is satisfied based on the terminal position information, the recommended handover execution completion position information, and the radio wave reception level, and determining whether or not the handover execution condition is satisfied Start executing the handover. Therefore, if there is a temporary drop in the radio wave reception level, it is not determined that the execution condition is satisfied, and the handover is not started. Therefore, the occurrence of the ping-pong phenomenon and unnecessary handover can be reduced.

  In the above configuration as a wireless communication system, the base station side control device updates the handover map stored in the handover map server based on the handover execution completion position information. Therefore, as compared with the prior art described in Patent Document 1 in which the H point is not updated, for example, it is possible to quickly cope with a change in a point where a handover should be performed, such as a building is built. .

  In the configuration of the first aspect, the number of handover map servers is arbitrary. Therefore, for example, as in the invention described in claim 2 or 3, a handover map server is provided for each of a plurality of communication base stations, and the plurality of handover map servers are associated in advance among a plurality of communication base stations. It may be configured to be able to communicate with a single communication base station.

  However, when the handover map in the case where the communication base station associated with the handover map server having the storage device is a serving base station is stored in the handover map server side storage device, As in the described invention, the base station side communication device not only performs wireless communication with the terminal, but also performs communication with the base station side communication device possessed by another communication base station. When receiving the handover execution completion position information from the terminal by the base station side communication apparatus, the side control apparatus transmits this handover execution completion position information to the serving base station before executing the handover, while the base station side If the communication apparatus receives handover execution completion position information from another communication base station, the communication base having the base station side control apparatus By sending a handover execution completion position information associated beforehand handover map server, to update the handover map handover map server stores.

  Accordingly, a recommended position for completion of handover from one communication base station serving as a serving base station to the other communication base station serving as a target base station, and the other serving as a serving base station from one communication base station serving as a target base station Even when the recommended position for completion of handover to the communication base station is different, the handover can be executed at an appropriate position.

  The handover map server-side storage device has a common handover map regardless of whether the communication base station associated with the handover map server having the storage device is a serving base station or a target base station. If stored, the base station side communication device not only performs wireless communication with the terminal, but also the base station side possessed by other communication base stations. The base station side control device also communicates with the communication device. When the base station side communication device receives the handover execution completion position information from the terminal by the base station side communication device, the base station side control device and the base station before executing the handover While transmitting this handover execution completion position information to a handover map server previously associated with a communication base station having a station side control device When the handover execution completion position information is received from another communication base station by the base station side communication apparatus, the handover execution completion position is stored in the handover map server previously associated with the communication base station having the base station side control apparatus. The handover map stored in the handover map server may be updated by transmitting the information.

  In the configuration described in claim 1, for example, as in the invention described in claim 4, one handover map server is provided for a plurality of communication base stations. It may be configured to be able to communicate with each other. However, in this case, the base station side communication device not only performs wireless communication with the terminal, but also performs communication with the handover map server, and the base station side control device performs base station side communication. When the handover execution completion position information is received from the terminal by the device, not only the handover execution completion position information but also the identification information of the serving base station before starting the handover and the communication base station By transmitting the identification information, the handover map stored in the handover map server is updated.

  In the configuration according to claim 4, as in the invention according to claim 5, the handover map server-side storage device includes a case where the communication base station is a serving base station for each of a plurality of communication base stations. It is desirable to store a handover map. Accordingly, a recommended position for completion of handover from one communication base station serving as a serving base station to the other communication base station serving as a target base station, and the other serving as a serving base station from one communication base station serving as a target base station Even when the recommended position for completion of handover to the communication base station is different, the handover can be executed at an appropriate position.

  In the configuration described in claim 4, as in the invention described in claim 6, the handover map server side storage device is common to a plurality of communication base stations, and the communication base station is the target. A common handover map may be stored regardless of whether it is a base station or a serving base station.

  Further, in the configuration according to any one of claims 1 to 6, as in the invention according to claim 7, the terminal is located within a predetermined range centered on the recommended handover execution completion position under the predetermined handover execution condition. In addition, it is preferable that the reception level of the radio wave received from the target base station is greater than or equal to the reception level of the radio wave received from the serving base station.

  In the configuration according to claim 7, since the terminal is located within a predetermined range centered on the recommended position for completion of handover, the terminal does not immediately perform handover from the serving base station to the target base station. It is possible to perform handover from the serving base station to the target base station after the reception state becomes better when performing wireless communication with the target base station than when performing wireless communication with the base station. .

  In the configuration described in claim 7, as in the invention described in claim 8, handover execution completion frequency information, which is frequency information at a position where the handover has been completed, is stored in the handover map. The handover map is composed of a plurality of lattice areas partitioned by a plurality of latitudes and meridians, and the base station side control device has a lattice area in which the frequency of completion of handover within the lattice area is a predetermined threshold or more. It is recommended that the center position of is a recommended position for completion of handover.

  However, in the configuration according to claim 8, as in the invention according to claim 9, the base station side control device is configured such that the predicted movement route of the terminal is a communication base station having the base station side control device. If the communication area passes through a grid area equal to or greater than a predetermined threshold but does not enter the communication area of the communication base station located around the communication base station from the communication area of the communication base station having the base station side control device. It is desirable that the center position of the lattice area not be a recommended position for completion of handover execution. As a result, the handover is not started even when the terminal passes through the lattice area equal to or greater than the predetermined threshold value, so that unnecessary handover can be avoided.

  Further, in the configuration according to claim 8 or 9, as in the invention according to claim 10, the base station side control device is a communication base in which the predicted movement route of the terminal has the base station side control device. When entering a communication area of a communication base station located in the vicinity of the communication base station from the communication area of the station, if a plurality of grid areas continuously exceeding a predetermined threshold are passed, It is desirable that the center position of the lattice area that passes first among the areas is a recommended position for completion of handover execution. As a result, when the terminal passes through a plurality of lattice areas that are equal to or greater than the predetermined threshold, that is, when an area suitable for handover continues, the handover can be completed at an early timing.

  In the configuration according to any one of claims 8 to 10, in the invention according to claim 11, the predetermined range centered on the recommended handover execution completion position is a lattice area centered on the recommended handover execution completion position and It is a region including at least a part of an adjacent lattice region.

  In the configuration according to claim 11, for example, a terminal is located in the adjacent grid area within the predetermined range due to, for example, a building being built, and the radio wave received from the target base station When there are many situations where the reception level is equal to or higher than the reception level of the radio wave received from the serving base station, the adjacent grid area becomes a grid area equal to or greater than a predetermined threshold, and the center position of the adjacent grid area is the recommended position for completion of handover execution. Can be. Since the handover map is updated in this way, it becomes possible to quickly cope with a change in a point where handover is to be performed. The predetermined range may be a circular shape in plan view centered on the recommended position for completion of handover execution, or a rectangular shape in plan view centered on the recommended position for completion of handover execution.

  By the way, for example, when the terminal is mounted on a vehicle, when the terminal is carried by a user who moves on foot, when the terminal is carried by a user who moves on a train such as a bullet train, etc. In FIG. 2, since the moving speeds of the terminals are different, the sizes of the lattice areas are different, and the recommended handover execution completion positions are different. Therefore, it is desirable to execute handover using a handover map corresponding to the moving speed of the terminal.

  Therefore, in the configuration of the eleventh aspect, as in the invention of the twelfth aspect, the storage device on the handover map server side corresponds to a speed band predetermined for the average moving speed of the terminal. A plurality of attached handover maps are stored, the communication base station has a base station side terminal moving speed acquisition means for acquiring the moving speed of the terminal, and the base station side control device is an average of the terminals The recommended location for handover execution completion is determined using a handover map associated with the speed band to which the moving speed belongs, and a lattice area that is information about the recommended position for completion of handover execution and the size of the lattice area of the used handover map. The information is transmitted to the terminal by the base station side communication device, and the terminal side control device receives the recommended location information and the grid area received by the terminal side communication device. Based on the information, it is desirable that the terminal determines whether located within the predetermined range around the handover execution completion recommended position.

  Alternatively, as in the invention according to claim 13, the handover map server side storage device stores a plurality of handover maps associated with a predetermined speed band with respect to the average moving speed of the terminal, The communication base station has base station side terminal moving speed acquisition means for acquiring the moving speed of the terminal, and the terminal has a wide grid area that forms a plurality of handover maps associated with the speed bands. In addition to storing lattice area information, which is information about the distance, the mobile station has a terminal-side terminal moving speed acquisition means for acquiring the moving speed of the terminal. The handover execution completion recommended position is determined using the handover map associated with the speed band to which the average moving speed belongs, and the handover execution completion recommended position information is obtained by the base station side communication device. The terminal side control device determines the handover map used by the communication base station based on the moving speed of the terminal acquired by the terminal side terminal moving speed acquisition means, and transmits to the terminal. Based on the recommended handover execution completion position information received by the communication apparatus and the lattice area information stored in the terminal, it is determined whether the terminal is located within a predetermined range centered on the recommended handover execution completion position. It is desirable to do.

  According to the configuration of the above twelfth or thirteenth aspect, handover according to the average speed band of the moving speed of the terminal can be executed.

  By the way, in the configuration according to claim 12 or 13, as a base station side terminal moving speed acquisition means, the base station side control device is based on the terminal location information received by the base station side communication device. It is good to get the moving speed of. Further, as the terminal side terminal moving speed acquisition means, the terminal side control device may acquire the moving speed of the terminal based on the terminal position information acquired by the terminal position information acquisition means. For example, when mounted on a vehicle, the moving speed of the terminal may be acquired from a vehicle speed sensor mounted on the vehicle.

  In the configuration according to any one of the first to thirteenth aspects, as in the invention according to the fourteenth aspect, the predicted travel route is calculated by the terminal-side control device and served by the terminal-side communication device. It may be transmitted to the base station, and the base station side control device of the communication base station may calculate the predicted movement route of the terminal as in the invention described in claim 15. In the configuration described in claim 14 or 15, as in the invention described in claim 16, the predicted travel route is determined based on destination information and map information that are destination information of the terminal. It is good to calculate.

  Since the handover map can be used as an out-of-service map, the wireless communication system may have an out-of-service map in addition to the handover map. That is, in the configuration according to any one of claims 1 to 16, as in the invention according to claim 17, further comprising an out-of-service map server, the out-of-service map server is information on a plurality of communication base station positions. Communication base station position information, position information where communication cannot be performed with the terminal, communication impossible position information, and position where communication with the terminal cannot be performed A non-service map server-side storage device that stores an out-of-service map information in which communication incompetence frequency information that is frequency information is stored, and an out-of-service map server-side communication device that can communicate with a communication base station, The side control device performs predetermined out-of-service processing based on the terminal location information acquired by the terminal location information acquisition means and the out-of-service processing completion completion recommended location information received by the terminal-side communication device. When it is determined whether or not the execution condition is satisfied, and when it is determined that the out-of-service processing execution condition is satisfied, the execution of the predetermined out-of-service processing is started, and wireless communication with the communication base station becomes possible. The terminal-side communication device transmits incommunicable position information, which is information on the position at which wireless communication can no longer be performed between the terminals, and the base station-side control device receives the terminal position received by the base station-side communication device. Based on the information, the out-of-service map stored in the out-of-service map server, and the predicted travel route of the terminal, the out-of-service processing completion recommended position that is the position that recommends the execution completion of out-of-service processing is determined. Out-of-service execution completion recommended position information, which is information on recommended execution completion position, is transmitted to the terminal by the base station side communication device, and based on the incommunicable position information received by the base station side communication device Out-of-service map server may update the out-of-range map to be stored.

It is a schematic diagram which shows the connection relation of a terminal, a communication base station, and a map server about one Embodiment of the radio | wireless communications system which concerns on this invention. It is a block diagram which shows the structural example of a vehicle-mounted terminal about the radio | wireless communications system of this Embodiment. It is a block diagram which shows the structural example of a communication base station about the radio | wireless communications system of this Embodiment. It is a block diagram which shows the structural example of a map server about the radio | wireless communications system of this Embodiment. It is a figure which shows an example of HO map about the radio | wireless communications system of this Embodiment. It is a figure which shows the relationship between the density | concentration of the lattice area | region which comprises HO map, and the execution completion frequency of a handover about the radio | wireless communications system of this Embodiment. (A) is a figure which shows an example of the HO map at the time of handing over from the said communication base station to another communication base station about the HO map which each two adjacent communication base stations have, (b) It is a figure which shows an example of the HO map at the time of handing over from the said communication base station to the said communication base station. It is a figure which shows an example of the prediction movement route | route which passes through several continuous boundary area | regions, when entering the communication area of a target base station from the communication area of a serving base station about the radio | wireless communications system of this Embodiment. (A) About the radio | wireless communications system of this Embodiment, when entering into the communication area of a target base station from the communication area of a serving base station, it is a figure which shows the prediction movement route which passes through one boundary area | region. (B) is a figure which shows an example of the numerical map which converted the HO map. (C) is the figure which extracted the prediction movement route from the numerical map. (A)-(d) is a figure for demonstrating the operation | movement about the radio | wireless communications system of this Embodiment. It is a flowchart which shows the process sequence about the terminal side process performed by the terminal which comprises the radio | wireless communications system of this Embodiment. It is a flowchart which shows the process sequence about the communication base station side process performed by the communication base station which comprises the radio | wireless communications system of this Embodiment. It is a figure for demonstrating the effect about the radio | wireless communications system of this Embodiment. It is a figure which shows the condition where the vehicle carrying a vehicle-mounted terminal moves along a path | route about the conventional radio | wireless communications system. In the situation shown in FIG. 14, the transition of the reception level of the radio wave received by the in-vehicle terminal from the nearby communication base station and the transition of the reception level of the radio wave received by the in-vehicle terminal from the distant communication base station. is there.

  An embodiment of a radio communication system according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, in this embodiment, the wireless communication system 1 includes an in-vehicle terminal 10 (not shown in FIG. 1) mounted on a vehicle C and a plurality of communication base stations 20 (1 in FIG. 1). Only one) and a handover map server 30 (only one is shown in FIG. 1). The wireless communication system 1 performs wireless communication with the in-vehicle terminal 10 among the plurality of communication base stations 20 using a handover map (hereinafter also referred to as HO map) stored in the handover map server 30. Next, the serving base station SB, which is a communication base station, performs radio communication with the in-vehicle terminal 10 from among the plurality of communication base stations 20 located around the serving base station SB. A handover for switching to the target base station TB which is a communication base station is executed.

  Hereinafter, configurations of the in-vehicle terminal 10, the communication base station 20, and the HO map server 30 of the wireless communication system 1 will be described.

  FIG. 2 is a block diagram showing a configuration example of the in-vehicle terminal 10. As shown in FIG. 2, the in-vehicle terminal 10 includes a terminal-side control device 11, a GPS receiver 12, a terminal-side storage device 13, an input device 14, and a terminal-side wireless communication device 15. The vehicle speed sensor 16 is provided. The terminal-side control device 11 is configured by a computer having a known CPU and a built-in memory, and the CPU realizes various functions by executing programs stored in a built-in memory (not shown). . In the following description, as a function realized by the program, as shown in FIG. 2, the terminal-side control device 11 includes a terminal location information acquisition unit 111, a predicted travel route calculation unit 112, and a terminal side as shown in FIG. A description will be given assuming that the controller 113 is included.

  The GPS receiver 12 is a known GPS receiver that receives a GPS signal transmitted from a GPS satellite (not shown in FIGS. 1 and 2) using an antenna. The GPS receiver 12 is connected to the terminal-side control device 11, receives a GPS signal at predetermined intervals, and outputs the received GPS signal to the terminal-side control device 11.

  The terminal-side storage device 13 is composed of a known hard disk drive device, flash memory, or the like, and is connected to the terminal-side control device 11. In this terminal-side storage device 13, the identification information of the in-vehicle terminal 10, map information for searching for a route to the destination, and information about the size of the lattice area of the HO map, which will be described later, Information and the like are stored, and are appropriately read out by the terminal-side control device 11. In addition, as will be described later, the terminal-side storage device 13 includes, in the terminal-side storage device 13, identification information of the target base station TB, HO execution completion recommended position information that is a position that recommends completion of handover, The HO execution completion position information, which is the position where the handover has been completed, is written or read as appropriate. The HO execution completion recommended position information and the HO execution completion position information correspond to the handover execution completion recommended position information and the handover execution completion position information described in the claims, respectively.

  The input device 14 is configured by an appropriate input device such as a touch panel or a voice input device, and is connected to the terminal-side control device 11. The user of the in-vehicle terminal 10 operates the input device 14 to input destination information, which is destination information, to the terminal-side control device 11 and sets the destination in the in-vehicle terminal 10. be able to.

  The terminal-side wireless communication device 15 is a known wireless communication device configured with an antenna, and is connected to the terminal-side control device 11. The terminal-side wireless communication device 15 is controlled by the terminal-side control device 11 and receives radio waves transmitted from adjacent base stations while performing wireless communication with the serving base station SB. The terminal-side wireless communication device 15 corresponds to the terminal-side communication device described in the claims.

  The vehicle speed sensor 16 is a known vehicle speed sensor mounted on the vehicle C, and is connected to the terminal-side controller 11. When the vehicle speed sensor 16 detects the vehicle speed that is the speed of the vehicle C, the vehicle speed sensor 16 outputs vehicle speed information that is information of the detected vehicle speed to the terminal-side control device 11. The vehicle speed sensor 16 corresponds to the terminal-side terminal moving speed acquisition means described in the claims, and the vehicle speed corresponds to the moving speed of the in-vehicle terminal 10.

  The terminal location information acquisition unit 111 is connected to the GPS receiver 12, takes in a GPS signal from the GPS receiver 12 at every predetermined time, and uses the information included in the taken-in GPS signal to install the in-vehicle terminal The terminal position information which is the position information of the machine 10 is acquired. Incidentally, the terminal location information is latitude information, longitude information, and altitude information of the in-vehicle terminal 10. Further, the terminal location information acquisition unit 111 is connected to the predicted movement route calculation unit 112 and the terminal side control unit 113, respectively, and the terminal location information acquired in this way is predicted and moved every predetermined time interval. It outputs to the route calculation part 112 and the terminal side control part 113, respectively. The GPS receiver 12 and the terminal location information acquisition unit 111 correspond to the terminal location information acquisition means described in the claims.

  The predicted travel route calculation unit 112 is connected to the input device 14, the terminal location information acquisition unit 111, the terminal side storage device 13, and the terminal side control unit 113. When the destination is set by the input device 14, the predicted travel route calculation unit 112 receives the terminal location information acquired by the terminal location information acquisition unit 111 when the destination is set, and the input device 14 inputs the terminal location information. Using the destination information and the map information stored in the terminal-side storage device 13, a route from the position of the in-vehicle terminal 10 to the destination at the time of setting the destination is calculated, and the calculated route is The predicted travel route of the in-vehicle terminal 10 is assumed. Then, the predicted travel route calculation unit 112 outputs predicted travel route information that is information on the predicted travel route to the terminal-side control unit 113.

  The terminal side control unit 113 is connected to the terminal position information acquisition unit 111, the predicted travel route calculation unit 112, the terminal side storage device 13, the terminal side wireless communication device 15, and the vehicle speed sensor 16, respectively.

  When the in-vehicle terminal 10 is not performing wireless communication with the serving base station SB, for example, at the start of the in-vehicle terminal 10, for example, the terminal-side control unit 113 is connected to the terminal-side wireless communication device 15. Is determined as the serving base station SB, and the terminal-side radio communication device 15 starts radio communication with the serving base station SB. Incidentally, as will be described later, the radio wave received by the terminal-side radio communication device 15 includes the identification information of the communication base station 20 that transmitted the radio wave. In the present embodiment, the terminal-side control unit 113 determines the communication base station 20 having the strongest reception level of the radio wave received by the terminal-side wireless communication device 15 as the serving base station SB. The communication base station 20 with the shortest linear distance from 10 may be determined as the serving base station SB.

  In addition, when the terminal location information is input from the terminal location information acquisition unit 111, the terminal side control unit 113 reads the identification information of the in-vehicle terminal 10 from the terminal side storage device 13, and the terminal side radio The communication device 15 is controlled to transmit the terminal location information together with the identification information of the in-vehicle terminal 10 to the serving base station SB. Similarly, when the predicted travel route information is input from the predicted travel route calculation unit 112, the terminal-side control unit 113 reads the identification information of the in-vehicle terminal 10 from the terminal-side storage device 13, and the terminal-side wireless The communication device 15 is controlled to transmit the predicted travel route information together with the identification information of the in-vehicle terminal 10 to the serving base station SB.

  Also, when the terminal-side wireless communication device 15 receives the HO execution completion recommended position information and the identification information of the target base station TB from the serving base station SB, the terminal-side control unit 113 receives the HO execution completion recommended position information from the serving base station SB. Predetermined handover execution conditions based on the acquired terminal location information, the HO execution completion recommended location information received by the terminal-side wireless communication device 15, and the reception level of the radio wave received by the terminal-side wireless communication device 15 Determine the success or failure. In the present embodiment, as the handover execution condition, the in-vehicle terminal 10 is located within a predetermined range centered on the recommended HO execution completion position, and the reception level of the radio wave received from the target base station TB is serving. It is adopted that it is higher than the reception level of the radio wave received from the base station SB.

  Specifically, the terminal-side control unit 113 first determines the HO map used in the serving base station SB using the vehicle speed information input from the vehicle speed sensor 16. When determining the HO map, the terminal-side control device 113 reads the lattice area information stored in the terminal-side storage device 13, and the in-vehicle terminal 10 is within a predetermined range centered on the recommended HO execution completion position. It is judged whether it is located in. When the terminal-side control device 113 determines that the in-vehicle terminal 10 is located within a predetermined range centered on the recommended HO execution completion position, the reception level of the radio wave received from the target base station TB is determined at the time of the determination. It is determined whether or not the reception level is higher than the radio wave received from the base station SB. Then, when determining that the reception level of the radio wave received from the target base station TB is equal to or higher than the reception level of the radio wave received from the serving base station SB, the terminal side control unit 113 determines from the serving base station SB. Starts handover to the target base station TB. On the other hand, when determining that the reception level of the radio wave received from the target base station TB is lower than the reception level of the radio wave received from the serving base station SB, the terminal-side controller 113 determines from the serving base station SB. Does not start executing handover to the target base station TB. As long as it is determined that the in-vehicle terminal 10 is located within a predetermined range centered on the recommended HO execution completion position, the terminal-side control unit 113 repeatedly performs the determination regarding the strength of the reception level.

  In addition, the terminal-side control unit 113 completes the handover from the serving base station SB to the target base station TB, and then the in-vehicle terminal 10 acquired by the terminal location information acquisition unit 111 when the handover is completed. The HO execution completion position information, which is the position information of the mobile station, and the identification information of the serving base station SB before starting the execution of the handover, the serving base station after the completion of the handover by the terminal-side radio communication device 15 It transmits to SB (that is, target base station TB before starting execution of handover).

  3 and 4 are block diagrams respectively showing a configuration example of the communication base station 20 and a configuration example of the HO map server 30. 3 and 4, only one communication base station 20 and one HO map server 30 are shown for convenience of illustration, but the wireless communication system 1 of the present embodiment includes a plurality of communication base stations 20. The HO map server 30 is provided for each of the plurality of communication base stations. The plurality of HO map servers 30 are configured to be capable of wired communication with one communication base station 20 associated in advance among the plurality of communication base stations 20.

  Specifically, as illustrated in FIG. 3, the communication base station 20 includes a base station side control device 21, a base station side wireless communication device 25, a first base station side wired communication device 27, and a second base station side. And a wired communication device 28.

  Among these, the base station side control device 21 is configured by a computer having a known CPU and a built-in memory, and the CPU realizes various functions by executing programs stored in a built-in memory (not shown). Yes.

  The base station side wireless communication device 25 is a known wireless communication device that includes an antenna and is capable of wireless communication, and is connected to the base station side control device 21. The base station side wireless communication device 25 is controlled by the base station side control device 21 and can perform wireless communication with the in-vehicle terminal 10 (specifically, the terminal side wireless communication device 15).

  The first base station side wired communication device 27 is a known wired communication device and is connected to the base station side control device 21. The first base station side wired communication device 27 is controlled by the base station side control device 21 and is associated with the communication base station 20 having the first base station side wired communication device 27 (specifically, the HO map server 30). It is possible to perform wired communication with the HO map server side wired communication device 37) described later.

  The second base station side wired communication device 28 is a known wired communication device and is connected to the base station side control device 21. The second base station side wired communication device 28 is controlled by the base station side control device 21, and other communication base stations 20 other than the communication base station having the second base station side wired communication device 28 (in detail, the first base station side control device 21). It is possible to perform wired communication with the two base station side wired communication devices 28).

  Incidentally, the base station side wireless communication device 25, the first base station side wired communication device 27, and the second base station side wired communication device 28 correspond to the base station side communication device described in the claims.

  The communication base station 20 configured as described above operates as follows. That is, when the communication base station 20 is activated, the base station side control device 21 controls the base station side wireless communication device 25, and is configured by a non-volatile memory or the like included in the base station side control device 21, for example. The radio wave including the identification information of the communication base station 20 stored in the memory that is not transmitted is transmitted to the surroundings at predetermined time intervals (for example, “0.1 [seconds]).

  Also, the base station side control device 21 receives the terminal location information and the terminal identification information transmitted by the terminal side wireless communication device 15 by the base station side wireless communication device 25, and adds the received terminal location information to the received terminal location information. Based on this, the moving speed of the in-vehicle terminal 10 and the average moving speed per unit time are calculated. The base station side control device 21 corresponds to the base station side terminal moving speed acquisition means described in the claims. Also, the base station side control device 21 receives the predicted movement route information and the terminal identification information transmitted by the terminal side wireless communication device 15 by the base station side wireless communication device 25.

  Also, the base station side control device 21 uses the terminal identification information to determine whether or not both the terminal location information and the predicted travel route information have been received for the same in-vehicle terminal 10 and the same If it is determined that both the terminal location information and the predicted travel route information have been received for the in-vehicle terminal 10, the in-vehicle out of a plurality of HO maps to be described later based on the average moving speed of the in-vehicle terminal 10 at the time of reception. The first base station side wired communication device 27 sends a transmission request for requesting transmission of an HO map associated with a predetermined speed band with respect to the average moving speed of the terminal 10 to the HO map server side wired communication device 37. Send to.

  Also, when the base station side control device 21 receives the HO map by the first base station side wired communication device 27, the HO execution completion recommended position and the target base station TB, which are positions where the completion of handover execution is recommended, will be described later. The base station side wireless communication apparatus 25 transmits the HO execution completion recommended position information and the identification information of the target base station TB to the terminal side wireless communication apparatus 15 by the determination method.

  When the base station side control device 21 determines that the HO execution completion position information and the serving base station SB identification information (before the execution of the handover is started) are received by the base station side wireless communication device 25, the reception is received. The second base station side wired communication device 28 transmits the average moving speed information and the HO execution completion position information, which are information of the average moving speed of the in-vehicle terminal at the time, to the serving base station SB before the execution of the handover is started. On the other hand, if it is determined that the HO execution completion position information has been received by the second base station side wired communication device 28, the average moving speed information that is information on the average moving speed of the in-vehicle terminal at the time of reception and the received HO execution The completion position information is transmitted to the HO map server 30 by the first base station side wired communication device 27. The HO map server 30 to which the HO execution completion position information is transmitted in this way updates the HO map based on the received HO execution completion position information.

  As shown in FIG. 4, the HO map server 30 includes a HO map server side control device 31, a HO map server side storage device 33, and a HO map server side wired communication device 37. .

  Among these, the HO map server side control device 31 is constituted by a computer having a known CPU and a built-in memory, and the CPU implements various functions by executing a program stored in a built-in memory (not shown). ing.

  The HO map server side storage device 33 is composed of a known hard disk drive device, flash memory, or the like, and is connected to the HO map server side control device 31. The HO map server side storage device 33 corresponds to the handover map server side storage device described in the claims.

  The HO map server-side storage device 33 stores a plurality of handover maps associated with a predetermined speed band with respect to the average moving speed of the in-vehicle terminal 10. Specifically, in the HO map server side storage device 33, for example, the average moving speed of the in-vehicle terminal 10 assuming that the vehicle C in which the in-vehicle terminal 10 is mounted is traveling on a general road in a traffic jam. “Less than 10 [km / hr]”, “10 [km / hr” is the average moving speed of the in-vehicle terminal 10 assuming that the vehicle C on which the in-vehicle terminal 10 is mounted is traveling on a non-congested general road. ] To 60 [km / hour] and the average moving speed of the in-vehicle terminal 10 assuming that the vehicle C on which the in-vehicle terminal 10 is mounted is traveling on a highway is “60 [km / hour] or more” “3” handover maps associated with a predetermined speed band such as “” are stored. As a result, the handover map in which the HO execution completion position information corresponding to the average moving speed of the in-vehicle terminal 10 is accumulated is stored in the HO map server side storage device 33.

  Further, the HO map server side storage device 33 does not store a common handover map regardless of whether the communication base station 20 is the serving base station SB or the target base station TB. A handover map when the communication base station 20 is the serving base station SB is stored.

  The HO map server side wired communication device 37 is a known wired communication device, and is connected to the HO map server side control device 31. The HO map server side wired communication device 37 is controlled by the HO map server side control device 31 to perform wired communication with the communication base station 20 associated with the HO map server 30 in advance. The HO map server side wired communication device 37 corresponds to the handover map server side communication device described in the claims.

  The HO map server 30 configured as described above operates as follows. That is, when the HO map server side control device 31 receives the transmission request by the HO map server side wired communication device 37, the HO map server side control device 31 reads out the HO map associated with the requested speed band from the HO map server side storage device 33, The read HO map is transmitted by the HO map server side wired communication device 37. Further, when the HO map server side control device 31 receives the average moving speed information and the HO execution completion position information by the HO map server side wired communication device 37, the HO map server side control device 31 stores a plurality of HO maps stored in the HO map server side storage device 33. The HO map associated with the speed zone to which the average moving speed information belongs is updated.

  FIG. 5 shows an example of the HO map. As shown in FIG. 5, the HO map includes a plurality of latitude lines having a predetermined interval and a lattice region defined by a plurality of meridians spaced by a predetermined interval. In the present embodiment, for example, as the predetermined interval, for example, “10 [m]”, “10 [km / hour] to 60 [km / hour” for a speed zone of “less than 10 [km / hour]”. ] For example, “50 [m]” and “60 [km / hour] or more” for example, “100 [m]” are associated with the speed zone.

  In this HO map, information on the position of the communication base station 20 associated with the HO map server 30 having the HO map server-side storage device 33 for storing the HO map, and adjacent positions located around the communication base station 20 Communication base station position information including information on the position of the base station, execution completion position information that is information on a position where the handover from the serving base station SB to the target base station TB is completed, and a position where the handover is completed Execution completion frequency information that is frequency information is accumulated.

  Here, the serving base station SB is the communication base station 20 associated with the HO map server 30 here, and the target base station TB is any one of the adjacent base stations here. The communication base stations 20, and the position information of these communication base stations 20 are indicated by the positions in the HO map of figures (see FIG. 5) and characters (such as “BS” in FIG. 1) indicating the communication base station 20. .

  In the present embodiment, the HO execution completion position information and the HO execution completion frequency information are indicated by the position of the lattice area and the density of the lattice area in the HO map. Specifically, with reference to the handover execution completion count of the most frequent lattice area among the lattice areas constituting the HO map, the reference values “80 [%]”, “60 [%]”, “40 [ %] ”And“ 20 [%] ”and the like, thresholds of“ 4 [pieces] ”are set, and the density of the lattice area is set to the density of“ 5 [steps] ”according to the arrival mode of these thresholds. (See FIG. 6). For this reason, the HO execution completion position information and the HO execution completion frequency information are indicated by the position of the lattice area in the HO map and the density of “5 [stage]” of the lattice area. By the way, the higher the density of the lattice area, the higher the frequency of completion of handover in that lattice area. The lower the density of the lattice area, the lower the frequency of completion of handover in that lattice area. Means. The HO execution completion frequency information corresponds to the handover execution completion frequency information described in the claims.

  In this embodiment, a lattice area including an execution completion position having a frequency equal to or higher than the threshold value of the reference value “80 [%]” is set as a boundary area. Note that the threshold value “80 [%]” of the reference value corresponds to the predetermined threshold value described in the claims.

  Further, in the present embodiment, the density of the lattice area constituting the HO map is set, for example, before the communication of the sufficient number of HO execution completion position information and HO execution completion frequency information in the HO map. Is determined in advance based on the reach of the radio wave calculated from the electric field strength of the radio wave transmitted from the mobile phone, the topography around the communication base station 20, and the like.

  FIG. 7 shows another example of the HO map. FIG. 7A is an example of an HO map when the communication base station 20 is the serving base station SB, and FIG. 7B shows an HO map when the communication base station 20 is the target base station TB. It is an example of a map. As shown in FIGS. 7A and 7B, for example, when communication areas of two adjacent communication base stations 20 overlap each other, HO from one communication base station 20 to the other communication base station 20 The recommended execution completion position may be different from the recommended HO execution completion position from the other communication base station 20 to the one communication base station 20. Therefore, in order to execute a handover at an appropriate point, the HO map server side storage device 33 has a common regardless of whether the communication base station 20 is the serving base station SB or the target base station TB. Instead of storing a handover map, a handover map in the case where the communication base station 20 is the serving base station SB is stored.

  The in-vehicle terminal 10, the communication base station 20, and the HO map server 30 configured as described above will be further described in detail.

  As described above, the in-vehicle terminal 10 (specifically, the terminal-side control unit 113) determines that the in-vehicle terminal 10 is located within a predetermined range centered on the recommended HO execution completion position as part of the handover execution condition. I was deciding whether to do it. Here, the relationship between the predetermined range centering on the recommended HO execution completion position, the predetermined interval between the plurality of parallels constituting the lattice area of the HO map, and the predetermined interval between the plurality of meridians will be described.

  In the present embodiment, the predetermined range centered on the recommended HO execution completion position employs an area including at least a part of the lattice area centered on the recommended HO execution completion position and its adjacent lattice area.

  Therefore, the terminal-side storage device 13 has a predetermined interval between a plurality of parallels and a predetermined interval between a plurality of meridians as lattice area information, which is information about the size of the lattice area of the HO map. When the in-vehicle terminal 10 determines whether or not the in-vehicle terminal 10 is located within a predetermined range centered on the recommended HO execution completion position as a part of the handover execution condition. Works as follows.

  That is, the terminal-side control unit 113 first determines the HO map used in the serving base station SB using the vehicle speed information input from the vehicle speed sensor 16. When the used HO map is determined, the terminal-side control device 113 reads information about the predetermined interval associated with the determined HO map from the terminal-side storage device 13. When the information about the predetermined interval is read, the terminal-side control unit 113 determines whether or not the in-vehicle terminal 10 is located within a predetermined range centered on the recommended HO execution completion position.

  Further, as described above, when the communication base station 20 (specifically, the base station-side control device 21) receives the HO map from the HO map server 30, the recommended HO execution completion recommended position that is a position that recommends completion of handover execution. And the target base station TB is determined. Hereinafter, the determination method of the recommended HO execution completion position executed by the base station side controller 21 will be described in detail with reference to FIGS. 8 and 9 in addition to FIG.

  Here, FIG. 5 and FIG. 9A are diagrams showing the predicted moving route R that passes through the “one” boundary region when entering the communication area of the target base station TB from the communication area of the serving base station SB. is there. However, although the predicted movement route R shown in FIG. 9A passes through the “plurality” boundary regions before passing through the “one” boundary region, the predicted movement route shown in FIG. The route R does not pass through “a plurality of” continuous boundary regions until it passes through “one” boundary region. FIG. 8 is a diagram showing a predicted moving route R that continuously passes through a “plurality” boundary region when entering the communication area of the target base station TB from the communication area of the serving base station SB. 5, 8, and 9 indicate the predicted travel route R of a certain in-vehicle terminal 10, and the position of the in-vehicle terminal 10 indicated by a rectangle in FIGS. 5, 8, and 9 is It means the position of the in-vehicle terminal 10 at the time when both the terminal position information and the predicted travel route information are received with respect to the same in-vehicle terminal 10, that is, when the transmission request is transmitted to the HO map server 30.

  When the base station side control device 21 receives both the terminal location information and the predicted travel route information for the same in-vehicle terminal 10 and receives the HO map, the base station side control device 21 receives the boundary on the predicted travel route R of the in-vehicle terminal 10. The center position of the area is set as a recommended HO execution completion position (see FIG. 5).

  However, the base station side control device 21 determines that the predicted movement route R of the in-vehicle terminal 10 is a communication base station 20 located in the vicinity of the communication base station 20 from the communication area of the communication base station 20 (serving base station SB). When a plurality of boundary regions pass continuously when entering the communication area of the (target base station TB), the center position of the boundary region that passes first among the plurality of consecutive lattice regions is HO. The recommended execution completion position is set (see FIG. 8).

  In addition, the base station side control device 21 is configured so that the predicted travel route R of the in-vehicle terminal 10 passes through the boundary area within the communication area of the communication base station 20 (serving base station SB), but the serving base station SB When the communication area does not enter the communication area of the communication base station 20 (target base station TB) located around the communication base station 20, the center position of the boundary area is not set as the recommended HO execution completion position (FIG. 9). (See (a)).

  In summary, the base station-side control device 21 first converts the HO maps shown in FIGS. 5, 8, and 9A to “−1”, “0”, “1” shown in FIG. 9B. ”Is converted into a numerical map digitized. “1” indicates a lattice area in the communication area of the serving base station SB, “−1” indicates a lattice area in the communication area of the target base station TB, and “0” indicates a serving area. This indicates a boundary area between the communication area of the base station SB and the communication area of the target base station TB. Then, as shown in FIG. 9 (c), the base station side control device 21 includes “0” sandwiched between “−1” and “1” in the numerical sequence corresponding to the predicted travel route R. The center position of the lattice area corresponding to the first “0” is set as the recommended HO execution completion position.

  FIG. 10A is a schematic diagram showing a process of step S101 described later executed by the wireless communication system 1, and FIG. 10B shows a process of step S104 described later executed by the wireless communication system 1. It is the schematic diagram which showed a series of processes from the judgment process of step S105. FIG. 10C is a schematic diagram showing a series of processes from a determination process in step S106 described later to a determination process in step S110 executed by the wireless communication system 1, and FIG. FIG. 5 is a schematic diagram showing a process of step S111 described later executed by the wireless communication system 1. FIG. 11 is a flowchart showing a processing procedure of the terminal side processing S1 executed by the in-vehicle terminal 10, and FIG. 12 is a flowchart showing a processing procedure of the base station side processing S2 executed by the communication base station 20. is there. Hereinafter, the operation of the wireless communication system 1 will be described with reference to FIGS.

  As shown in FIG. 11 and FIG. 10A, the in-vehicle terminal 10 starts to execute the terminal-side processing S1, and is transmitted from the GPS satellite G and received by the GPS receiver 12 as processing in step S101. Terminal position information is acquired using information included in the GPS signal. When the terminal location information is acquired, the in-vehicle terminal 10 proceeds to the determination process in the subsequent step S102.

  In step S102, the in-vehicle terminal 10 determines whether the destination information is input and the destination is set. Here, when the in-vehicle terminal 10 does not determine that the destination has been set (“No” in the determination process in step S102), the determination process in step S102 is executed again, while the destination is set. If it is determined (“Yes” in the determination process in step S102), the process proceeds to the subsequent step S103. In other words, the in-vehicle terminal 10 stands by until the destination is set through the determination process in step S102. When the destination is set, the in-vehicle terminal 10 proceeds to the subsequent step S103.

  When the process proceeds to step S103, the in-vehicle terminal 10 calculates a route from the position of the in-vehicle terminal 10 to the destination at the time of affirmative determination in step S102 (that is, at the time of setting the destination), and the calculation is performed. The route to the destination is set as the predicted travel route of the in-vehicle terminal 10. When the predicted travel route is calculated, the in-vehicle terminal 10 proceeds to the subsequent step S104.

  After shifting to the process of step S104, the in-vehicle terminal 10 as shown in FIG. 10 (b), various information, specifically, the terminal location information and the terminal identification information, the terminal location information and the prediction. The travel route information is transmitted to the serving base station SB. When these various types of information are transmitted, the in-vehicle terminal 10 proceeds to the determination process in the subsequent step S105.

  When the process proceeds to the determination process in step S105, the in-vehicle terminal 10 determines whether or not the HO execution completion recommended position information and the identification information of the target base station TB are received from the serving base station SB as shown in FIG. Judging. Here, when the in-vehicle terminal 10 does not determine that the HO execution completion recommended position information and the identification information of the target base station have been received (“No” in the determination process of step S105), the determination process of step S105 When the HO execution completion recommended position information and the target base station identification information are determined to have been received (“Yes” in the determination process of step S105), the process proceeds to the subsequent determination process of step S106. In other words, the in-vehicle terminal 10 stands by until receiving the HO execution completion recommended position information and the identification information of the target base station TB from the serving base station SB through the determination process of step S105. When receiving the HO execution completion recommended position information and the identification information of the target base station TB from the serving base station SB, the in-vehicle terminal 10 proceeds to the determination process in the subsequent step S106.

  When the process proceeds to the determination process of step S106, the in-vehicle terminal 10 uses the position information, vehicle speed information, HO execution completion recommended position information, and lattice area information, as shown in FIG. It is determined whether 10 is located within a predetermined range centered on the recommended HO execution completion position. Here, if the in-vehicle terminal 10 does not determine that the vehicle-mounted terminal 10 is located within the predetermined range (“No” in the determination process of Step S106), the vehicle-mounted terminal device 10 executes the determination process of Step S106 again while being positioned within the predetermined range. If it is determined (“Yes” in the determination process of step S106), the process proceeds to the subsequent determination process of step S107.

  After shifting to the determination process in step S107, the in-vehicle terminal 10 determines that the reception level of the radio wave received from the target base station TB at the time of the affirmative determination in step S106 is the serving base station SB as shown in FIG. It is judged whether it is more than the reception level of the electric wave received from.

  Here, when it is determined that the reception level of the radio wave received from the target base station TB is equal to or higher than the reception level of the radio wave received from the serving base station SB (“Yes” in the determination process of step S107), that is, the above handover execution condition Is determined, it is better to perform wireless communication with the target base station TB rather than wireless communication with the serving base station SB. Therefore, the in-vehicle terminal 10 starts executing handover from the serving base station SB to the target base station TB as the processing of the subsequent step S108.

On the other hand, when it is not determined that the reception level of the radio wave received from the target base station TB is equal to or higher than the reception level of the radio wave received from the serving base station SB (“No” in the determination process in step S107), the target base station TB This means that it is better to perform wireless communication with the serving base station SB than wireless communication with the serving base station SB. Therefore, the in-vehicle terminal 10 executes the determination process in step S107 again without starting execution of handover from the serving base station SB to the target base station TB. In other words, the in-vehicle terminal 10 determines in step S107. Wait until the wireless communication with the target base station TB is better than the wireless communication with the serving base station SB through the processing. Start execution of handover to the station. The in-vehicle terminal 10 determines whether or not the handover is completed as the determination process in the subsequent step S109. Here, when the in-vehicle terminal 10 does not determine that the handover has been completed (“No” in the determination process of step S109), the in-vehicle terminal 10 executes the determination process of step S109 again while determining that the handover has been completed. (“Yes” in the determination process in step S109), the process proceeds to the subsequent step S110. In other words, the in-vehicle terminal 10 waits until the handover from the serving base station SB to the target base station TB is completed through the determination process in step S109. Incidentally, the in-vehicle terminal 10 determines that the handover is completed when the throughput is recovered after the handover from the serving base station SB to the target base station TB.

  When the process proceeds to step S110, the in-vehicle terminal 10 acquires position information at the time of an affirmative determination of the determination process in step S109 (that is, at the completion of handover) and executes HO, as shown in FIG. 10 (d). It is transmitted to the serving base station SB (target base station TB before completion of handover) as completion position information. When the process of step S110 is executed, the in-vehicle terminal 10 ends the terminal-side process S1.

  As shown in FIG. 12 and FIG. 10B, the communication base station 20 (here, the serving base station SB) starts executing the base station side process S2, and as the determination process in step S201, the same in-vehicle terminal 10 It is determined whether or not various types of information have been received, specifically, whether or not terminal location information and terminal identification information, as well as terminal location information and predicted travel route information have been received. Here, when the communication base station 20 does not determine that various information has been received (“No” in the determination process in step S201), the communication base station 20 executes the determination process in step S201 again, while receiving various information. If it is determined (“Yes” in the determination process in step S201), the process proceeds to the subsequent step S202. In other words, the communication base station 20 stands by until various information is received from the in-vehicle terminal 10 through the determination process of step S201.

  When the process proceeds to step S202, the communication base station 20 determines the average moving speed of the in-vehicle terminal 10 among the plurality of HO maps based on the average moving speed of the in-vehicle terminal 10 at the time of an affirmative determination in the determination process of step S201. Is transmitted to the HO map server 30 to request transmission of a HO map associated with a predetermined speed band, and the process proceeds to the determination process in step S203.

  In step S203, the communication base station 20 determines whether the HO map associated with the speed band is received from the HO map server 30. Here, when the communication base station 20 does not determine that the HO map has been received (“No” in the determination process in step S203), the communication base station 20 executes the determination process in step S203 again, while receiving the HO map. If it is determined (“Yes” in the determination process in step S203), the process proceeds to the subsequent step S204. In other words, the communication base station 20 stands by until receiving the HO map from the HO map server 30 through the determination process in step S203.

  When the process proceeds to step S204, the communication base station 20 identifies the boundary region and the target base station TB through which the predicted movement route passes when entering the communication area of the target base station TB from the communication area of the serving base station SB. Then, the process proceeds to the subsequent step S205. After shifting to the process of step S205, the communication base station 20 determines the first boundary area among the boundary areas specified in the process of step S204 as the recommended HO execution completion position.

  After shifting to the process of step S206, the communication base station 20 transmits the HO execution completion recommended position information and the identification information of the target base station TB to the terminal-side radio communication device 15 by the base station-side radio communication device 25, and subsequent steps. The process proceeds to the determination process of S207.

  When the process proceeds to the determination process in step S207, the communication base station 20 (here, neither the serving base station SB nor the target base station TB) receives the HO from the communication base station 20 (serving base station SB after the completion of the handover). It is determined whether or not execution completion position information has been received. Here, when the communication base station 20 does not determine that the execution completion position information has been received (“No” in the determination process in step S207), the communication base station 20 executes the determination process in step S207 again, while the HO execution completion position. When it is determined that the information has been received (“Yes” in the determination process in step S207), the process proceeds to the subsequent step S208. In other words, the communication base station 20 stands by until receiving the HO execution completion position information through the determination process of step S207. When receiving the HO execution completion position information, the communication base station 20 proceeds to the process of subsequent step S208.

  When the process proceeds to step S208, the communication base station 20 receives the HO map from the HO map server 30, updates the frequency of the HO map, and thus the concentration, and then sends the updated HO map to the HO map server 30. Send.

  In the wireless communication system 1 described above, the in-vehicle terminal 10 starts executing a handover when it is determined that a predetermined handover execution condition is satisfied based on the terminal position information, the recommended HO execution completion position information, and the radio wave reception level. At the same time, after the execution of this handover is completed, the HO execution completion position information and the identification information of the serving base station SB before starting the execution of the handover are transmitted to the serving base station SB after the completion of the handover. Further, the communication base station 20 determines the recommended HO execution completion position based on the terminal position information, the HO map, and the predicted movement route of the in-vehicle terminal 10, and the HO execution completion recommended position information and the target base station TB The identification information is transmitted to the in-vehicle terminal 10 and the HO map is updated based on the HO execution completion position information. As a result, the execution condition is not satisfied only by a temporary drop in the radio wave reception level, and the handover is not started. Therefore, the occurrence of the ping-pong phenomenon and unnecessary handover can be reduced. Moreover, the base station side control apparatus 21 updates the HO map which the HO map server 30 memorize | stores based on HO execution completion position information. Therefore, as compared with the prior art described in Patent Document 1 in which the H point is not updated, for example, it is possible to quickly cope with a change in a point where a handover should be performed, such as a building is built. .

  Further, in this embodiment, the communication base station 20 determines how much the boundary region R when the predicted movement route R of the in-vehicle terminal 10 does not enter the communication area of the target base station TB from the communication area of the serving base station SB. Even if it passes, the boundary area is not set as the recommended HO execution completion position. Therefore, for example, as shown in FIG. 13, before the predicted travel route R enters the communication area of the target base station TB from the communication area of the serving base station SB, the threshold value of “80 [%]” is exceeded. Even if the grid region P1 including the HO execution completion position, which is a low frequency, passes through the lattice region P1, the handover is not started because the lattice region P1 is not the HO execution completion recommended position, and the occurrence of ping-pong phenomenon and unnecessary handover is reduced. can do.

  In the present embodiment, the HO map server side storage device 33 stores a handover map when the communication base station 20 is the serving base station SB. Therefore, for example, as shown in FIGS. 7A and 7B, the recommended HO execution completion position from one communication base station 20 to the other communication base station 20 is one from the other communication base station 20. Unlike the recommended HO execution completion recommended position for the communication base station 20, even if the predicted travel route R passes through a portion where the communication areas of these communication base stations overlap, the completion recommendation set in the serving base station SB is set. By executing the handover according to the position, it is possible to repeatedly execute the handover between these two communication base stations, that is, to suppress the occurrence of the ping-pong phenomenon.

  The wireless communication system according to the present invention is not limited to the configuration exemplified in the above embodiment, and can be implemented with various modifications without departing from the spirit of the present invention. . In other words, for example, the following embodiment can be implemented by appropriately changing the above embodiment.

  In the above embodiment, the HO map server side storage device 33 stores the HO map when the communication base station 20 associated with the HO map server 30 having the storage device 33 is the serving base station SB. However, the communication base station 20 associated with the HO map server 30 having the storage device 33 is the serving base station SB or the target base station TB. Regardless of the case, a common handover map (for example, see FIG. 5) may be stored. In this case, however, the base station side communication device 21 not only performs wireless communication with the in-vehicle terminal 10 but also communicates with the base station side communication device 28 of the other communication base station 20. When the base station side control device 21 receives the HO execution completion position information from the in-vehicle terminal 10 by the base station side communication device 28, the base station side control device 21 and the serving base station SB before executing the handover and the base station side While transmitting this HO execution completion position information to the HO map server 30 previously associated with the communication base station 20 having the control device 21, the HO execution completion position is transmitted from the other communication base station 20 by the base station side communication device 28. When the information is received, the handover execution completion position information is transmitted to the HO map server 30 previously associated with the communication base station having the base station side control device 21 The Rukoto, may update the handover map HO map server 30 is stored.

  In the above embodiment, one HO map server 30 may be provided for a plurality of communication base stations 20 and configured to be able to communicate with the plurality of communication base stations 20. In this case, the base station side communication device 28 not only performs wireless communication with the in-vehicle terminal 10, but also performs communication with the HO map server 30, and the base station side control device 21 When the HO execution completion position information is received from the in-vehicle terminal 10 by the station side communication device 28, not only the HO execution completion position information but also the serving base station SB before starting the handover is sent to the HO map server 30. The handover map stored in the HO map server 30 is updated by transmitting the identification information and the identification information of the communication base station 20.

  In the above configuration, the HO server-side storage device 33 preferably stores a handover map for each of the plurality of communication base stations 20 when the communication base station 20 is the serving base station SB. Thereby, the recommended HO execution completion position from one communication base station 20 serving as the serving base station SB to the other communication base station 20 serving as the target base station TB, and from one communication base station 20 serving as the target base station TB Even if the HO execution completion recommended position for the other communication base station 20 serving as the serving base station SB is different, the handover can be executed at an appropriate position.

  Even in the above configuration, the HO server-side storage device 33 is common to a plurality of communication base stations 20, and it does not matter whether the communication base station 20 is a target base station TB or a serving base station. Alternatively, a common handover map may be stored.

  Moreover, in the said embodiment, although the vehicle-mounted terminal device 10 had the estimated movement route calculation part 112, the communication base station 20 may have a prediction movement route calculation part. Specifically, the communication base station 20 has an appropriate storage device that stores map information for route search. When receiving the destination information and the terminal location information from the in-vehicle terminal 10, the communication base station 20 The route from the position of the in-vehicle terminal 10 to the destination is calculated using the terminal location information and the map information, and the calculated route may be used as the predicted movement route of the in-vehicle terminal 10.

  Further, such a predicted travel route calculation unit may not calculate the predicted travel route based on the destination information and map information of the in-vehicle terminal 10. Even if the destination information is not used, for example, the position information that is the position information of the in-vehicle terminal 10 such as a predicted movement route such as a portion on the moving direction side of the road where the in-vehicle terminal 10 is located, The predicted travel route may be calculated based on the travel direction information that is the travel direction information and the map information.

  In the above embodiment, since the terminal is mounted on the vehicle C, the vehicle speed sensor 16 is adopted as the movement speed acquisition means for acquiring the movement speed of the terminal. The moving speed of the terminal may be acquired based on the amount of change in the position information.

  In the above embodiment, the base station side control device 21 determines the recommended HO execution completion position using the HO map associated with the speed band to which the average moving speed of the in-vehicle terminal 10 belongs, and completes the HO execution. The recommended position information is transmitted to the in-vehicle terminal 10 by the base station side wireless communication device 25. Then, the terminal-side control device 11 determines the HO map used by the communication base station 20 based on the moving speed of the in-vehicle terminal 10 acquired by the vehicle speed sensor 16 and received by the terminal-side wireless communication device 25. Based on the HO execution completion recommended position information and the lattice area information stored in the in-vehicle terminal 10, it is determined whether the in-vehicle terminal 10 is located within a predetermined range centered on the HO execution completion recommended position. Was going to do. However, the present invention is not limited to this configuration. That is, the HO map server-side storage device 33 stores a plurality of HO maps associated with a predetermined speed band with respect to the average moving speed of the in-vehicle terminal 10, and the communication base station 20 The in-vehicle terminal 10 stores lattice area information, which is information about the size of the lattice area constituting a plurality of HO maps associated with the speed band, based on the position information of the machine 10. And a vehicle speed sensor 16. Then, the base station side control device 21 determines the recommended HO execution completion position using the HO map associated with the speed band to which the average moving speed of the in-vehicle terminal 10 belongs, and obtains the recommended HO execution completion recommended position information from the base station. The terminal side control device 11 transmits the HO map used by the communication base station 20 based on the moving speed of the in-vehicle terminal 10 acquired by the vehicle speed sensor 16. Based on the recommended HO execution completion recommended position information received by the terminal-side wireless communication device 25 and the lattice area information stored in the in-vehicle terminal 10, the in-vehicle terminal 10 focuses on the recommended HO execution completion position. It is determined whether or not it is located within a predetermined range. Also by this, the handover can be executed using the HO map corresponding to the moving speed of the in-vehicle terminal 10.

  Moreover, in the said embodiment, although the radio | wireless communications system 1 was provided with the vehicle-mounted terminal device 10 mounted in the vehicle C, it is not restricted to the vehicle-mounted terminal device 10. It is good also as a structure which has a terminal portable about a user.

  Further, since the boundary area is an area located at the boundary of the serving base station communication area, the HO map can also be used as an out-of-service map. Therefore, in addition to the HO map, an out-of-service map may be provided. Specifically, the wireless communication system may be configured as follows.

  The wireless communication system includes an out-of-service map server in addition to the HO map server. This out-of-service map server includes communication base station position information that is position information of a plurality of communication base stations, incommunicable position information that is information of a position at which wireless communication with an in-vehicle terminal cannot be performed, and An out-of-service map server-side storage device that stores an out-of-service map in which communication incompetence frequency information, which is frequency information at a position where wireless communication with the in-vehicle terminal can no longer be performed, and a communication base station; And an out-of-service map server side communication device capable of communicating with each other. Here, the communication disabled position information and the communication disabled frequency information correspond to the HO execution completion position information and the HO execution completion frequency information, respectively.

  The terminal-side control device 11 has predetermined out-of-service processing execution conditions based on the terminal location information acquired by the terminal location information acquisition unit 111 and the out-of-service execution completion recommended position information received by the terminal-side wireless communication device 15. Determine the success or failure. The out-of-service process execution condition is, for example, that the in-vehicle terminal 10 is positioned within a predetermined range centered on the out-of-service process execution completion recommended position. When the terminal-side control device 11 determines that the out-of-service processing execution condition is satisfied, for example, a notification process for notifying the user of the in-vehicle terminal 10 that “there is a possibility that it will soon be out of the service area” or important data is transmitted. Execution of predetermined out-of-service processing such as data transmission / reception processing that advances the transmission / reception timing is started. The terminal-side control device 11 is communication that is information on a position at which wireless communication with the communication base station 20 can no longer be performed after wireless communication with the communication base station 20 becomes possible. The impossible position information is transmitted by the terminal-side wireless communication device 15. Here, the recommended out-of-service execution completion position corresponds to the recommended handover execution completion position, the out-of-service processing execution condition corresponds to the handover execution condition, and the notification process and the data transmission / reception process correspond to the handover.

  The base station side control device 21 performs out-of-service processing based on the terminal location information received by the base station-side wireless communication device 25, the out-of-service map stored in the out-of-service map server, and the predicted travel route of the in-vehicle terminal 10. The recommended out-of-service execution completion recommended position, which is the position where the execution completion is recommended, is determined. The base station-side control device 21 transmits out-of-service process execution completion recommended position information, which is information of the determined out-of-service process execution completion recommended position, to the in-vehicle terminal 10 by the base station-side wireless communication device 25, and thus the base station-side wireless communication The out-of-service map stored in the out-of-service map server is updated based on the communication disabled position information received by the device 25.

DESCRIPTION OF SYMBOLS 1 ... Wireless communication system, 10 ... In-vehicle terminal, 11 ... Terminal side control apparatus, 111 ... Terminal location information acquisition part, 112 ... Predictive movement route calculation part, 113 ... Terminal side communication control part, 12 ... GPS reception 13 ... Terminal side storage device, 14 ... Input device, 15 ... Terminal side wireless communication device, 16 ... Vehicle speed sensor, 20 ... Communication base station, 21 ... Base station side control device, 25 ... Base station side wireless communication 27, first base station side wired communication device, 28 ... second base station side wired communication device, 30 ... handover map server, 31 ... handover map server side control device, 33 ... handover map server side storage device, 37 ... Handover map server side wired communication device.

Claims (17)

A serving base station comprising a terminal, a plurality of communication base stations, and a handover map server, wherein the serving base station is a communication base station that performs radio communication with the terminal among the plurality of communication base stations. Handover to switch from adjacent base stations, which are communication base stations located around the serving base station, to a target base station, which is a communication base station that performs radio communication with the terminal, among communication base stations A wireless communication system for performing
The handover map server stores a handover map in which communication base station position information which is position information of the plurality of communication base stations and handover execution completion position information which is information of a position where the handover has been completed are stored. A map server side storage device, and a handover map server side communication device capable of communicating with the communication base station,
The terminal is
Terminal location information acquisition means for acquiring terminal location information that is location information of the terminal;
A terminal-side communication device that receives radio waves transmitted from the adjacent base station while performing wireless communication with the serving base station;
While transmitting the terminal location information acquired by the terminal location information acquisition means to the serving base station by the terminal side communication device,
Based on the terminal location information acquired by the terminal location information acquisition means, the handover execution completion recommended location information received by the terminal side communication device, and the reception level of the radio wave received by the terminal side communication device When it is determined whether or not a predetermined handover execution condition is satisfied, and when it is determined that the handover execution condition is satisfied, execution of the handover is started based on the identification information of the target base station received by the terminal side communication device ,
After the execution of this handover is completed, the handover execution completion position information, which is information on the position at which this handover has been completed, and the serving base station identification information before the execution of this handover is performed by the terminal side communication device, A terminal side control device that transmits to the serving base station after the completion of this handover,
The communication base station is
A base station side communication device capable of wireless communication with the terminal,
Based on the terminal location information received by the base station side communication apparatus, the handover map stored in the handover map server, and the predicted travel route of the terminal, the location recommending completion of the handover A handover execution completion recommended position is determined, and the handover execution completion recommended position information, which is information of the determined handover execution completion recommended position, and identification information of the target base station are transmitted to the terminal by the base station side communication device. Send
A radio communication system comprising: a base station side control device that updates the handover map stored in the handover map server based on the handover execution completion position information received by the base station side communication device. The wireless communication system according to claim 1, wherein
The handover map server is provided for each of the plurality of communication base stations, and the plurality of handover map servers can communicate with one communication base station associated in advance among the plurality of communication base stations. Configured,
The handover map server side storage device stores a handover map when the communication base station associated with the handover map server having the storage device is a serving base station,
The base station side communication device not only performs wireless communication with the terminal, but also performs communication with base station side communication devices possessed by other communication base stations,
When the base station side control apparatus receives the handover execution completion position information from the terminal by the base station side communication apparatus, the base station side control apparatus transmits the handover execution completion position information to the serving base station before executing the handover. On the other hand, when the base station side communication device receives the handover execution completion position information from another communication base station, the handover map server associated in advance with the communication base station having the base station side control device A wireless communication system, wherein the handover map stored in the handover map server is updated by transmitting the handover execution completion position information. The wireless communication system according to claim 1, wherein
The handover map server is provided for each of the plurality of communication base stations, and the plurality of handover map servers can communicate with one communication base station associated in advance among the plurality of communication base stations. Configured,
The handover map server-side storage device stores a common handover map regardless of whether the communication base station associated with the handover map server having the storage device is a serving base station or a target base station. Has been
The base station side communication device not only performs wireless communication with the terminal, but also performs communication with base station side communication devices possessed by other communication base stations,
When the base station side control apparatus receives the handover execution completion position information from the terminal by the base station side communication apparatus, the base station side control apparatus sets the serving base station and the base station side control apparatus before executing the handover. When the handover execution completion position information is transmitted from the other communication base station by the base station side communication device while the handover execution completion position information is transmitted to the handover map server previously associated with the communication base station having Updating the handover map stored in the handover map server by transmitting the handover execution completion position information to a handover map server associated in advance with the communication base station having the base station side control device A wireless communication system. The wireless communication system according to claim 1, wherein
The handover map server is provided for the plurality of communication base stations, and is configured to be able to communicate with the plurality of communication base stations,
The base station side communication device not only performs wireless communication with the terminal, but also performs communication with the handover map server,
When the base station side control apparatus receives the handover execution completion position information from the terminal by the base station side communication apparatus, the base station side control apparatus performs not only the handover execution completion position information but also the handover to the handover map server. A wireless communication system, wherein the handover map stored in the handover map server is updated by transmitting identification information of a serving base station before starting execution and identification information of the communication base station. The wireless communication system according to claim 4, wherein
The wireless communication system, wherein the handover map server side storage device stores, for each of the plurality of communication base stations, a handover map when the communication base station is a serving base station. The wireless communication system according to claim 4, wherein
The handover map server-side storage device stores a common handover map that is common to the plurality of communication base stations, regardless of whether the communication base station is a target base station or a serving base station. A wireless communication system. The wireless communication system according to any one of claims 1 to 6,
In the predetermined handover execution condition, the terminal is located within a predetermined range centered on the recommended position for completion of handover execution, and the reception level of the radio wave received from the target base station is received from the serving base station. A wireless communication system characterized in that it includes a radio wave reception level or higher. The wireless communication system according to claim 7,
In the handover map, handover execution completion frequency information that is frequency information at a position where the handover has been completed is stored,
This handover map is composed of a plurality of lattice areas partitioned by a plurality of latitudes and meridians,
The base station side control device is characterized in that a handover execution completion recommended position is a center position of a lattice area in which a frequency of completion of handover within a lattice area is a predetermined threshold value or more. The wireless communication system according to claim 8,
The base station side control device is configured to control the base station side control while the predicted travel route of the terminal passes through a lattice area equal to or greater than the predetermined threshold within a communication area of a communication base station having the base station side control device. If the communication area of the communication base station having the apparatus does not enter the communication area of the communication base station located around the communication base station, the center position of the lattice area is not set as the recommended position for completion of handover. A wireless communication system. The wireless communication system according to claim 8 or 9,
When the base station side control device enters the communication area of the communication base station located around the communication base station from the communication area of the communication base station having the base station side control device, the predicted movement route of the terminal In addition, when a plurality of lattice regions that are equal to or greater than the predetermined threshold value are continuously passed, the center position of the lattice region that passes first among the plurality of consecutive lattice regions is set as the recommended handover execution completion position. A wireless communication system. In the radio | wireless communications system as described in any one of Claims 8-10,
The wireless communication system, wherein the predetermined range centered on the handover execution completion recommended position is an area including at least a part of a lattice area centered on the handover execution completion recommended position and an adjacent lattice area. The wireless communication system according to claim 11, wherein
The handover map server side storage device stores a plurality of handover maps associated with a predetermined speed band with respect to the average moving speed of the terminal,
The communication base station has base station side terminal moving speed acquisition means for acquiring the moving speed of the terminal,
The base station side control apparatus determines the handover execution completion recommended position using a handover map associated with a speed band to which the average moving speed of the terminal belongs, and uses the handover execution completion recommended position information and the used position information Transmitting lattice area information, which is information about the size of the lattice area of the handover map, to the terminal by the base station side communication device;
The terminal-side control device is located within a predetermined range centered on the handover execution completion recommended position based on the recommended position information and the lattice area information received by the terminal-side communication device. A wireless communication system characterized by determining whether or not. The wireless communication system according to claim 11, wherein
The handover map server side storage device stores a plurality of handover maps associated with a predetermined speed band with respect to the average moving speed of the terminal,
The communication base station has base station side terminal moving speed acquisition means for acquiring the moving speed of the terminal,
The terminal stores lattice area information, which is information about the size of a lattice area constituting a plurality of handover maps associated with the speed band, and acquires a moving speed of the terminal It has machine side terminal movement speed acquisition means,
The base station side control device determines the handover execution completion recommended position using a handover map associated with a speed band to which the average moving speed of the terminal belongs, and determines the handover execution completion recommended position information as the base station Transmitted to the terminal by the side communication device,
The terminal-side control apparatus determines a handover map used by the communication base station based on the moving speed of the terminal acquired by the terminal-side terminal moving speed acquisition means, and the terminal-side communication apparatus Whether the terminal is located within a predetermined range centered on the recommended position for completion of handover execution based on the recommended position information for completion of handover execution and the lattice area information stored in the terminal. A wireless communication system characterized by: In the radio | wireless communications system as described in any one of Claims 1-13,
The wireless communication system, wherein the predicted travel route is calculated by the terminal-side control device and transmitted to the serving base station by the terminal-side communication device. In the radio | wireless communications system as described in any one of Claims 1-13,
The wireless communication system, wherein the base station side control device of the communication base station calculates a predicted movement route. The wireless communication system according to claim 14 or 15,
A wireless communication system, characterized in that the predicted travel route is calculated based on destination information and map information which are information on a destination of the terminal. In the radio | wireless communications system as described in any one of Claims 1-16,
It also has an out-of-service map server
The out-of-service map server includes communication base station position information, which is position information of the plurality of communication base stations, and incommunicable position information, which is information of a position at which wireless communication with the terminal cannot be performed. An out-of-service map server-side storage device that stores the stored out-of-service map, and an out-of-service map server-side communication device that can communicate with the communication base station,
The terminal-side control device has a predetermined out-of-range processing execution condition based on the terminal location information acquired by the terminal location information acquisition unit and the out-of-range processing execution completion recommended location information received by the terminal-side communication device. When the success / failure is determined and it is determined that the out-of-service processing execution condition is satisfied, the execution of the predetermined out-of-service processing is started, and wireless communication with the communication base station is enabled. Incommunicable position information that is information on the position where wireless communication can no longer be performed is transmitted by the terminal side communication device,
The base station side control device, based on the terminal location information received by the base station side communication device, an out-of-service map stored in the out-of-service map server, and a predicted travel route of the terminal, The out-of-service process execution completion recommended position, which is a position that recommends execution completion of the process, is determined, and the out-of-service process execution completion recommended position information that is the information of the determined out-of-service process execution completion recommended position is transmitted by the base station side communication device to the terminal The out-of-service map stored in the out-of-service map server is updated based on the incommunicable position information transmitted to the mobile station and received by the base station side communication device.

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