JP4831572B2 - Mobile communication system - Google Patents

Description

  The present invention relates to a mobile communication system that can predict a movement route of a wireless terminal such as a mobile phone in communication.

  A plurality of radio base stations are distributed and arranged so that their service areas partially overlap, and a radio terminal communicating with a radio base station moves in a direction away from the service area of the radio base station In this case, in order to continue communication, it is necessary to perform processing for switching to the destination radio base station. However, if a situation occurs in which a radio channel cannot be secured due to resources required for communication, for example, congestion, etc., at the destination radio base station, the radio terminal cannot continue communication.

  In order to solve such a problem, conventionally, a radio base station detects, for example, a change in the incident angle of a radio wave due to a change in a reception level from a radio terminal by a directional antenna, and a position of the radio terminal and the change thereof. The position information indicating the moving speed and direction of the wireless terminal is detected, and this position information is collected at a control station higher than the wireless base station, and the wireless terminal There has been proposed a system for predicting a destination and instructing the predicted radio base station to secure resources (see, for example, Patent Document 1).

  In the system that provides the CDMA system, the upper control station of the radio base station collects the location information of the radio terminal from the radio base station, and determines the current location of the radio terminal, the moving speed, and the moving direction. A system has been proposed in which a wireless base station that sets a required path is determined by referring to a path number map in which a required number of paths is determined in advance based on map information (for example, Patent Document 2). reference).

In addition, a GPS (Global Positioning System) unit is provided in the wireless terminal, and the position information obtained by positioning and the time information at that time are transmitted to the base station, transferred to the movement prediction device via this base station, and the change in position information. Based on the time information and the travel speed, the travel speed and the travel direction are obtained, the travel route information such as roads and railways based on the map information is referred to, the travel route of the wireless terminal is predicted, and the current wireless base station is communicating. Predicting the time to reach a service area that can communicate with an adjacent radio base station, reserving a radio channel for a destination radio base station, and a destination radio base station and radio channel for a radio terminal A system for notifying information has been proposed (see, for example, Patent Document 3).
Japanese Patent Laid-Open No. 11-103479 JP 2000-217138 A JP 2004-228881 A

  By performing the movement prediction of the wireless terminal and securing the resources of the movement-destination wireless base station, it is possible to control the wireless terminal moving at high speed so as to maintain the continuation of communication. In that case, it is possible to obtain the moving direction and the moving speed based on the change of the position information of the wireless terminal over time, which is also described in Patent Documents 1 to 3 described above. In general, when moving along a road, for example, there are a plurality of movement paths of a wireless terminal from the current position. Therefore, in order to improve movement direction prediction accuracy, position information is acquired at short time intervals. Need to get. In addition, the wireless terminal may be stopped or moving at a very low speed during communication. Therefore, until the end of communication, the wireless terminal communicates with the same wireless base station and can switch to the adjacent wireless base station. Sometimes not done.

  In the above-described conventional example, when the wireless terminal moves at high speed, the wireless terminal movement destination predicting means needs to shorten the position information acquisition time interval in order to improve accuracy. However, this increases the traffic between the wireless terminal and the wireless base station and between the wireless base station and the control station, and the problem of squeezing traffic for normal communication and transmission of location information at short time intervals Therefore, there is a problem of increase in power consumption of the wireless terminal.

  The present invention solves the conventional problems, and predicts the movement route of a wireless terminal economically, and also enables congestion prediction based on the prediction.

The mobile communication system of the present invention is a wireless terminal that obtains and holds movement information including position information indicating a current position of a wireless terminal, movement speed information of the wireless terminal, and movement direction information of the wireless terminal, moving includes moving prediction function unit for predicting a movement path of the wireless terminal by gathering continues the movement information of the wireless terminal, be on the moving path the moving prediction function unit predicts the wireless terminal The radio base station predicted to be the destination has a configuration for reserving resources for the radio terminal based on the resource usage status in the radio base station predicted to be the destination .

  The wireless terminal transmits the held movement information to the movement prediction function unit via the wireless base station and the base station control station in accordance with a transmission request or transmission condition instruction from the movement prediction function unit. It has a configuration to do.

  The movement prediction function unit predicts a movement path of the wireless terminal based on movement information from the wireless terminal, and when the prediction cannot be performed, continuously instructs the wireless terminal to transmit movement information, and predicts the movement path. In some cases, the mobile station has a configuration for notifying the base station control station of resource reservation when the destination radio base station along the movement path is short of resources.

  The mobile communication system including the wireless terminal, the wireless base station, the base station control station, and the movement prediction function unit is provided with a traffic congestion prediction function unit, and the traffic congestion prediction function unit is provided in the movement prediction function unit. The mobile terminal has a configuration for performing congestion prediction in the moving direction of the wireless terminal based on the number of wireless terminals indicating that the moving speed information included in the collected movement information of the wireless terminal has decreased to a predetermined speed or less. .

  The traffic jam prediction function unit is configured to notify the radio terminal of traffic jam prediction information or detour route information based on traffic jam prediction in the moving direction of the radio terminal.

  The wireless terminal transmits the movement information including the position information, the movement speed, and the movement direction in accordance with the movement information notification condition. For example, the movement information is transmitted from the wireless terminal in which the movement speed and the movement direction are changed. However, a wireless terminal that does not move does not need to transmit movement information continuously, and a wireless terminal that moves at a constant speed and in a certain direction Therefore, there is no need to continuously transmit the movement information at the stage where the movement prediction has been made, and there is an advantage that unnecessary traffic can be reduced. In addition, since the movement information from the wireless terminal includes position information, speed information, and direction information, the movement prediction function unit can quickly make a movement path prediction of the wireless terminal at the current position, and move at high speed. It is also possible to promptly notify the resource securing etc. at the radio base station that is the destination of the radio terminal to be moved. Thereby, even when the wireless terminal moves at a high speed, there is an advantage that communication can be continued.

  Further, based on the movement prediction information of the wireless terminal by the movement prediction function unit, the traffic congestion prediction function unit can predict the traffic route of the wireless terminal, and when the occurrence of the traffic congestion is predicted, the movement to the point There is an advantage that it is possible to notify congestion prediction information or detour route information for the predicted wireless terminal.

  Referring to FIG. 1, the mobile communication system of the present invention includes a wireless terminal 1 that can move in wireless areas of a plurality of wireless base stations 2-1 and 2-2, and a higher rank of the wireless base stations 2-1 and 2-2. In the mobile communication system including the base station control station 3, the wireless terminal 1 includes means for obtaining and holding movement information including position information, a movement speed, and a movement direction. The mobile prediction function unit 4 includes means for collecting the movement information held by the wireless terminal 1 via 1 and 2-2 and the base station control station 3, and the movement prediction function unit 4 includes the wireless terminal 1 1 is provided on the basis of the movement information collected from No. 1 so as to predict the movement path of the wireless terminal 1 and to reserve resources for the wireless base station to which the wireless terminal 1 is moving.

  FIG. 1 is an explanatory diagram of Embodiment 1 of the present invention, where 1 is a wireless terminal, 2-1, 2-2 are wireless base stations, 3 is a base station control station, 4 is a movement prediction function unit, and 5 is wireless Wireless terminal compatible information holding unit for holding terminal-compatible position information, moving speed information, and moving direction information, 6 is a wireless base station compatible information holding unit for holding information such as resources for wireless base stations, and 7 is wireless terminal compatible A prediction processing unit that performs determination and control processing such as information request and acquisition of wireless base station correspondence information is shown. Note that the wireless terminal correspondence information holding unit 5 by the memory constituting the movement prediction function unit 4, the wireless base station correspondence information holding unit 6, and the determination processing and control processing function means by a processor or the like are provided at the upper level of the wireless base station. It is also possible to configure as part of the control processing function of the base station control station 3.

  The wireless terminal 1 is remarkably improved in function and generally has a configuration capable of executing various application programs. In addition to the normal wireless communication means, there is provided a configuration including position information acquisition means for the current position, and means for obtaining a moving distance or moving speed and moving direction over time of the position information. As this position information acquisition means, for example, a position information acquisition means by a GPS unit that receives radio waves from a GPS satellite is generally used, and a configuration implemented in a wireless terminal such as a mobile phone is also known. Also, known means such as position information acquisition means based on the wireless base station based on the identification information of the wireless base station and the received power of the radio wave can be applied. It is also possible to apply means for receiving a radio wave from a distance post arranged along a road and identifying a position from a reference point.

  The wireless terminal 1 holds movement information including the current position information, movement speed information, and movement direction information, and starts the communication from the movement prediction function unit 4 to the base station control station 3 and the wireless base station 2- The wireless terminal correspondence information including the identification information of the wireless terminal 1 and the movement information is transmitted to the movement prediction function unit 4 according to the request via 1 or 2 or the notified transmission condition. That is, since the wireless terminal correspondence information including the identification information and movement information of the wireless terminal 1 is transmitted from the wireless terminal 1 only when movement prediction is necessary in the movement prediction function unit 4, It will not affect traffic.

  Further, the movement prediction function unit 4 collects information on the wireless terminal 1 in communication with the wireless base station from the base station control station 3, acquires the wireless terminal correspondence information of the wireless terminal 1 whose communication is started, and the wireless terminal Correspondence information is held in the wireless terminal correspondence information holding unit 5, and wireless base station correspondence information including resource usage statuses such as wireless channels of the wireless base stations 2-1 and 2-2 is collected to support the wireless base station. It is held in the information unit 6. The prediction processing unit 7 has map information, collects wireless terminal correspondence information from the wireless terminal 1 that has started communication, and based on the current position information, moving speed information, and moving direction information of the wireless terminal 1. Next, it is predicted whether or not to move to the service area of the adjacent radio base station. For example, when the current position of the wireless terminal 1 is approximately in the center of the service area of the wireless base station 2-1 and the moving speed indicates a stopped state, the wireless terminal 1 can move to the service area of the adjacent wireless base station. Therefore, even if the mobile communication duration is long, if the position information does not change, a transmission condition in which the mobile information is not transmitted can be set. When the wireless terminal 1 in communication moves, the position information may change and the moving speed may also change. If such a change occurs, the position information, the moving speed information, and the moving direction information are displayed. It is assumed that the movement information included is a transmission condition for transmitting to the movement prediction function unit 4.

  The movement prediction function unit 4 determines whether or not the mobile terminal 1 can move to the service area of the adjacent radio base station based on the current position information and the movement direction information when the moving speed of the wireless terminal 1 is high. When there is a high possibility of moving to the service area of the radio base station, the radio base station correspondence information including the resource usage status of the radio base station of the move destination secures resources for radio terminals with high mobility. The base station control station 3 is instructed so that it can be implemented in the previous radio base station. As a result, the wireless terminal 1 can smoothly perform the process of sequentially switching connection to a plurality of wireless base stations along the movement route.

  FIG. 2 shows a flowchart of processing for obtaining position information, moving speed information, and moving direction information in the wireless terminal, and the current position information of the wireless terminal is acquired by GPS or other means (A1). It is determined whether it is the same as the position information (A2). If the position information is the same as the previous position information, the wireless terminal is not moving, so this process ends or returns to the first step (A1). If the position information is different from the previous position information, the wireless terminal has moved, or if the position information is not acquired before the start of communication, the position information acquired by the start of communication is the previous position information. Since there is no state, the position information between the previous time and this time is different. In this case, if the difference between the previous position information and the current position information is equal to or greater than a preset value, it can be determined that the position information has moved.

  If the previous position information is different from the current position information, the movement distance and the movement direction are calculated based on the position information (A3). A moving speed is calculated based on the calculated moving distance and time information between the previous time and the current time (A4), and it is determined whether the moving information between the moving speed and the moving direction is different from the previous time (A5). When the previous movement information and the current movement information are the same, only the position information is changed, and the movement information is moving in the same direction at the same speed, and only this position information is updated (A8). If the movement information is different, the position information, the movement distance, and the movement direction are transmitted to the movement prediction function unit 4 via the radio base station (A6). Then, the transmitted content is saved (A7). Note that the information on the moving distance in this case can be the information on the moving speed calculated in step (A4).

  FIG. 3 is a flowchart showing the process of the movement prediction function unit. When movement information from a wireless terminal is acquired (B1), the movement route is based on position information, movement direction information, and movement distance information as the movement information. Prediction is performed (B2). In this case, when the movement route cannot be predicted, the wireless terminal is requested to continue transmission of movement information (B6), the process is terminated, and the process proceeds to the movement information acquisition step (B1). When the movement path can be predicted in step (B2), the switching of the radio base station is predicted (B3), and the shortage of resources in the destination radio base station due to the radio base station switching is predicted. (B4). When it is predicted that there will be no shortage of resources and there are few radio terminals communicating with this destination radio base station, this process is terminated, and if the resource shortage is predicted, the resources of the destination radio base station The base station control station is notified that reservation is necessary (B5), and this process is terminated.

  FIG. 4 is a prediction explanatory diagram of the movement route of the wireless terminal, and there are a plurality of routes that the wireless terminal (mounted on a road vehicle such as a passenger car) is expected to move, as shown as route 1 and route 2, for example. In order to specify the movement route, the movement information of the wireless terminal is required continuously. And when movement along the route 1 is predicted, it will pass through the wireless areas A, B, C, so before moving from the wireless area A to the wireless area C according to the position information of the wireless terminal, It is determined whether or not a resource shortage at the radio base station C is predicted, and if a resource shortage is predicted, the base station controller determines that resource reservation at the radio base station C is necessary. The base station control station notifies the radio base station C of the resource reservation. As a result, the wireless terminal can continue communication even after moving from the wireless area A to the wireless area C.

  If movement along the route 2 is predicted, the wireless area C does not pass through, and therefore, before moving from the wireless area A to the wireless area B, the resources in the wireless base station B are the same as described above. It is determined whether or not a shortage is predicted, and if a shortage of resources is predicted, as in the case described above, resources are secured in the radio base station B, and if a shortage of resources is not predicted, And Accordingly, even when moving along the route 2, the wireless terminal can move in the wireless area B while communicating from the wireless area A.

  FIG. 5 is an explanatory diagram of Embodiment 2 of the present invention, where the same reference numerals as those in FIG. 1 denote the same name parts, 8 denotes a traffic jam prediction function unit, and 9 denotes a traffic volume detection system. As described above, the movement prediction function unit 4 has a configuration including the wireless terminal correspondence information holding unit 5, the wireless base station correspondence information holding unit 6, and the prediction processing unit 7. It collects and performs movement route prediction. The traffic volume detection system 9 corresponds to a system for detecting the traffic volume of an arterial road such as an expressway that has already been put into practical use. The traffic congestion prediction function unit 8 is a function of the wireless terminal 1 from the movement prediction function unit 4. Based on the movement information and the traffic volume information from the traffic volume detection system 9, the occurrence of traffic jam is predicted. By this traffic jam prediction function unit 8, for example, traffic jam prediction information is notified to a wireless terminal heading to a location where traffic jam is predicted, and when there is a route that can bypass the traffic jam prediction point, the bypass route information is notified. . The traffic volume information of the traffic volume detection system 9 can be transferred to the traffic jam prediction function unit 8 via a dedicated network or a general-purpose network. The traffic volume information within the prediction determination range may be requested to the traffic volume detection system 9. It is also possible to make the main part of the traffic jam prediction function unit 8 and the movement prediction function unit 4 in common and to be provided in the base station control station 3.

  FIG. 6 is a flowchart of the traffic jam prediction function unit according to the second embodiment of the present invention, based on the traffic volume information from the traffic volume detection system 9 or the movement information of the wireless terminal 1 from the movement prediction function unit 4 or It is determined whether or not the number of vehicles passing the vehicle has reached the number that is expected to cause traffic congestion due to a decrease in speed (C1). If it has been reached, it requests the movement prediction function unit 4 to transmit the movement information notification condition of the wireless terminal that has moved into the area of the wireless base station (C2). For example, when the moving speed of the wireless terminal 1 is reduced to 50 km / h or less, the wireless terminal notifies the condition for transmitting the movement information.

  Thereby, the traffic jam prediction function unit 8 receives and collects movement information from the wireless terminals whose movement speed has decreased (C3), and the number of wireless terminals whose movement speed has decreased, that is, the number of vehicles whose speed reduction has been set in advance. It is determined whether or not a traffic jam is predicted, that is, whether or not a traffic jam is predicted (C4). If a traffic jam is not predicted, the process proceeds to step (C3), and the number of vehicles whose speed decreases exceeds a preset number. If the traffic jam occurs, the occurrence of the traffic jam is predicted (C5), and as described above, the traffic jam prediction information or the detour route information is notified to the wireless terminal heading for the traffic jam occurrence predicted point.

  FIG. 7 is an explanatory diagram of the moving route, showing the wireless areas A, B, and C of the wireless base stations A, B, and C, and the routes 1 and 2, respectively. This causes a decrease in the speed of a plurality of subsequent vehicles due to the decrease in the speed of the vehicle, and in particular causes a traffic jam at the junction of the routes 1 and 2. Therefore, a decrease in speed of a plurality of vehicles within a predetermined range at a certain point, for example, within a predetermined distance range in front of the above-described junction point is detected based on the movement information of the wireless terminal. Thereby, as described above, it is possible to predict the traffic jam of the vehicle heading to the meeting point. It is possible to notify the detour information by the traffic jam prediction and to avoid the actual traffic jam occurrence. Further, the movement information transmission request to the wireless terminal is a case where a traffic jam is predicted, and therefore there is no fear of increasing traffic.

It is explanatory drawing of Example 1 of this invention. It is a flowchart of the radio | wireless terminal of Example 1 of this invention. It is a flowchart of the movement prediction function part of Example 1 of this invention. It is prediction explanatory drawing of the movement path | route of Example 1 of this invention. It is explanatory drawing of Example 2 of this invention. It is a flowchart of the traffic congestion prediction function part of Example 2 of this invention. It is explanatory drawing of the movement path | route of Example 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wireless terminal 2-1 and 2-2 Wireless base station 3 Base station control station 4 Movement prediction function part 5 Wireless terminal corresponding | compatible information holding part 6 Wireless base station corresponding | compatible information holding part 7 Prediction processing part

Claims (8)

A wireless terminal that obtains and holds movement information including position information indicating a current position of the wireless terminal, movement speed information of the wireless terminal, and movement direction information of the wireless terminal;
A movement prediction function unit that predicts a movement route of the wireless terminal by continuously collecting the movement information of the wireless terminal ;
A radio base station that is on the movement path predicted by the movement prediction function unit and is predicted to be the destination of the wireless terminal is based on the resource usage status in the radio base station that is predicted to be the destination. A mobile communication system, wherein a resource for a radio terminal is reserved . The said wireless terminal is equipped with the structure which transmits the said movement information currently hold | maintained to the said movement prediction function part according to the transmission request or transmission condition instruction | indication from the said movement prediction function part. Mobile communication system. The movement prediction function unit, said continue to the wireless terminal tells the movement information transmitted when the unpredictable movement information from the wireless terminal, when the predicted moving path, the destination radio along the travel path The mobile communication system according to claim 1, further comprising a configuration for notifying a resource reservation to a base station control station that is a higher-order station of the radio base station when the base station is short of resources. Based on the movement speed information and the movement direction information included in the movement information of the wireless terminals collected by the movement prediction function unit, the number of wireless terminals in the same movement direction that have fallen below a predetermined speed is predetermined. The mobile communication system according to claim 1, further comprising a traffic jam prediction function unit that judges whether or not the number exceeds a traffic jam in the moving direction of the wireless terminal.   5. The mobile communication system according to claim 4, wherein the traffic jam prediction function unit is configured to notify the radio terminal of traffic jam prediction information or detour route information based on traffic jam prediction in the movement direction of the radio terminal. The movement prediction function unit continuously collects resource usage status information indicating a resource usage status in the radio base station predicted to be the destination, and is predicted as the destination based on the resource usage status information. The mobile communication system according to claim 1, further comprising a configuration for estimating a shortage of resources in a wireless base station. The movement prediction function unit is configured to reserve a resource for the wireless terminal when the wireless base station predicted to be the movement destination is predicted to have a shortage of resources in the wireless base station predicted to be the movement destination. The mobile communication system according to claim 6, further comprising: The movement prediction function unit reserves a resource for the wireless terminal to the wireless base station predicted to be the movement destination when a shortage of resources is predicted in the wireless base station predicted to be the movement destination. 8. The mobile communication system according to claim 7, wherein the mobile communication system is notified.

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