JP2016165069A - Mobile phone and system for radio communication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To implement both of suppression of power consumption of a mobile phone and a user's convenience, in a tunnel, a basement, etc.SOLUTION: A mobile phone for performing radio communication with a base station comprises: a tunnel information acquisition unit for acquiring tunnel information from the base station; a position information acquisition unit for acquiring position information on the mobile phone; a mode selection unit for selecting, on the basis of the tunnel information and the position information, one mode out of a plurality of modes for the radio communication's system selection; and a system selection unit for executing the radio communication's system selection on the basis of the selected mode.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a mobile phone and a wireless communication system.

  The cellular phone uses a cellular communication system, and communicates with a base station installed in each communication area. The mobile phone supports one or a plurality of communication methods, and when a plurality of communication methods are supported, the mobile phone selects a communication method according to a predetermined priority order and performs communication. Since mobile phones have limited battery capacity, it is important to reduce power consumption.

  When the mobile phone has completed the terminal registration process with the base station, the technology to adjust the timing to start communication with the base station and communicate with the base station for a minimum amount of time to reduce battery consumption. is there. However, if the mobile phone has not completed terminal registration processing with the base station, or if the mobile phone is in a state where it cannot communicate due to loss of radio waves from the base station (hereinafter referred to as an out-of-service state) The battery is depleted because the communication method that can receive incoming communication from is always searched.

  When the mobile phone goes out of service, a process called method selection is performed as the first step for restoring communication. The method selection is a process of selecting a communication method and a frequency to be used from communication standards that can be used by mobile phones such as LTE, 3G, and 2G, and is also described in Non-Patent Document 1, for example.

  As an example of a mobile phone going out of service, there may be a case where a radio wave temporarily stops, such as behind a building. In such a case, since there is a high possibility that the mobile phone will return to the area within a short time, the probability that the mobile phone communication will be restored every hour is high. On the other hand, there are cases where the mobile phone is out of service for a long time, such as when the mobile phone is in the basement. In such a case, the probability that the cellular phone communication is restored every hour is low.

  For this reason, when a mobile phone goes out of service, a method of gradually extending the interval for selecting a method along with the length of time that the mobile phone is out of service is generally widely implemented. . Thereby, power consumption can be suppressed by setting the sleep state while the method selection process is not performed.

  Also, for example, in Patent Document 1, it is determined that a temporary out-of-service state has occurred if the steepness of the change in the reception level up to the out-of-service state is judged to be steep beyond a certain level. Otherwise, it is determined as a long-term out-of-service state. If it is temporarily out of service, select a method at a short interval and try to quickly restore communication.If it is determined that the out-of-service state will continue for a long time, select a method at a long interval to reduce power consumption. Techniques for reducing are disclosed.

JP 2006-140912 A

"3GPP TS.23.122 Non-Access-Stratum (NAS) functions related to Mobile Station (MS) in idle mode", [online], 2011, 3GPP (registered trademark), [October 3, 2014 search] , Internet (URL: http://www.qtc.jp/3GPP/Specs/23122-8c0.pdf)

  If a general technique or the technique disclosed in Patent Document 1 is used, power consumption can be suppressed by extending the interval of method selection in an out-of-service state. However, depending on the location in the tunnel or the basement, power consumption is not reduced and the user's convenience is not compatible. For example, in the technique disclosed in Patent Document 1, especially when the reception level changes sharply, but the out-of-service state is not caused by a tunnel, for example, when entering a basement, until communication is recovered. Since the method selection continues to be performed at short intervals for a long period of time, power consumption increases.

  Therefore, the present invention aims to achieve both the suppression of power consumption of a mobile phone and the convenience of a user in a tunnel or a basement.

  A representative base station according to the present invention is a mobile phone that wirelessly communicates with a base station, a tunnel information acquisition unit that acquires tunnel information from the base station, and a location information acquisition that acquires location information of the mobile phone. Based on the tunnel information and the location information, a mode selection unit that selects one mode from a plurality of modes of the wireless communication method selection, and the wireless communication based on the selected mode. And a method selection unit for executing method selection.

  According to the present invention, it is possible to achieve both suppression of power consumption of a mobile phone and user convenience in a tunnel, a basement, and the like.

It is a figure which shows the example of a communication system. It is a figure which shows the example of tunnel information. It is a figure which shows the example of the relationship between normal mode and tunnel mode. It is a figure which shows the example of the timing of communication recovery in normal mode and tunnel mode. It is a figure which shows the example of the system configuration | structure of a mobile telephone. It is a figure which shows the example of the system configuration | structure of a base station. It is a sequence diagram which shows the example of the measurement switching control of position and speed information. It is a sequence diagram which shows the example of the mode switching control of a system selection. It is a figure which shows the example of the tunnel information in Example 2. FIG. It is a figure which shows the example of the relationship between normal mode and tunnel mode in Example 2. FIG. FIG. 10 is a diagram illustrating an example of communication recovery timing in a normal mode and a tunnel mode in the second embodiment. FIG. 10 is a diagram illustrating an example of a system configuration of a mobile phone according to a second embodiment.

  Hereinafter, examples will be described with reference to the drawings. In the description of the embodiment, a configuration using LTE (Long Term Evolution) will be described.

  FIG. 1 is a diagram illustrating an example of a communication system. The communication system includes a plurality of base stations 102, 104, 106 and a mobile phone 108. However, the communication system may include more base stations and mobile phones than the example of FIG. 1, or the base station 102 may not be provided. Communication areas 103, 105, and 107 are areas in which base stations 102, 104, and 106 can communicate, and are also referred to as cells.

  The base stations 102, 104, and 106 regularly notify the setting of the network type, communication timing, and the like using a downlink common control channel that is a channel that can be received by all mobile phones in the communication area. This is called notification information. The tunnel information is information indicating the position information of the entrance / exit of the tunnel in the communication area of the base station, and only the base station including the entrance / exit of the tunnel in the communication area reports. Specific contents of the tunnel information will be described later.

  In the example of FIG. 1, since the base station 102 does not include a tunnel entrance / exit in its communication area 103, the base station 102 performs notification that does not include tunnel information. Since the base station 104 has an entrance / exit of the tunnel 101 in its communication area 105, the broadcast information includes the tunnel information. In addition, since the base station 106 also includes the other entrance / exit of the tunnel 101 in its communication area 107, the broadcast information includes the tunnel information.

  Here, a base station having a tunnel entrance / exit in its own communication area such as the base station 104 and the base station 106 is called a base station near the tunnel. For this reason, the tunnel information is held by a base station near the tunnel. When the mobile phone 108 enters the communication area 107 of the base station 106 near the tunnel, the mobile phone 108 receives a notification including the tunnel information from the base station 106. This tunnel information is used when the mobile phone 108 enters the tunnel 101.

  FIG. 2 is a diagram illustrating an example of tunnel information. The tunnel information includes a tunnel ID and the latitude / longitude / altitude of the tunnel entrance / exit. The tunnel ID is an identifier assigned to the tunnel. The latitude / longitude / altitude of the entrance / exit of the tunnel is position information about the entrance / exit included in the communication area of the base station that broadcasts the tunnel information. In this example, the latitude / longitude and altitude are used to specify that the mobile phone 108 has moved to the entrance / exit position of the tunnel 101 using the GPS (Global Positioning System). Other types of information may be used as long as the telephone can identify the position of the entrance / exit of the tunnel.

  When each of the communication areas 105 and 107 includes a plurality of tunnel entrances, the tunnel information may include the latitude, longitude, and altitude of each tunnel entrance so that the tunnel information can be identified by a plurality of tunnel IDs. The tunnel information is information set for each base station by an operator who manages the system parameters of the base station in advance, and is stored in each base station. The stored tunnel information is included in the notification information and notified. The tunnel information may be updated to reflect the situation around the base station.

  The tunnel 101 may be a so-called tunnel, or may be a space constructed for the purpose of transporting or storing traffic between two points or a plurality of points and goods, or similar to the name of a tunnel or a tunnel. It may be a named space.

  FIG. 3 is a diagram illustrating an example of the relationship between the normal mode and the tunnel mode. The vertical axis in FIG. 3 represents the timing of system selection, and the horizontal axis represents the elapsed time since the mobile phone 108 was out of service. In this example, when the mobile phone 108 is in an out-of-service state, the mobile phone 108 performs mode selection in one of two modes, the normal mode and the tunnel mode, so that the mode is divided into two modes.

  In the normal mode, the cellular phone 108 selects a method so that the frequency gradually decreases, as in the conventional cellular phone. In the example shown in FIG. 3, the interval of method selection immediately after out of service is a0. When the time t1 elapses, the method selection interval becomes a1, which is wider than a0. When the time t2 is reached, the interval increases to a2, and at time t3, the interval for selecting the method further increases to a3. As described above, in the normal mode, the interval for selecting the method stepwise increases with time, and the frequency decreases.

  In the tunnel mode, the mobile phone 108 always keeps the frequency of method selection constant at the interval a0. With this process, the mobile phone 108 selects a method at a constant interval regardless of the elapsed time since the mobile phone 108 is out of service. Between the timing of method selection execution and the timing of the next method selection execution, the mobile phone 108 enters a sleep state and suppresses power consumption. For this reason, the power consumption can be greatly suppressed as the interval of method selection is wider.

  The intervals for selecting the normal mode and the tunnel mode may be set in advance from the outside of the mobile phone 108. Further, it may be set based on information included in radio waves received from base stations 102, 104, and 106.

  FIG. 4 is a diagram illustrating an example of a relationship of communication recovery timing after passing through the tunnel using each of the normal mode and the tunnel mode. In the case of passing through the tunnel using the normal mode, the frequency of selecting the method while the mobile phone 108 passes through the tunnel 101 decreases to the interval a3, and communication is performed for the first time at the time t4 when the method is first selected after passing through the tunnel. Recover. The expected value of the time from passing through the tunnel to recovering communication is a3 / 2.

  On the other hand, when the tunnel mode is used to pass through the tunnel, the method selection is always performed at regular intervals during the passage of the tunnel, so that communication is recovered at time t5 when the method selection is performed for the first time after passing through the tunnel. The expected value of the time from the passage of the tunnel to the recovery of the communication is a0 / 2. As described above, since it takes a long time to select a method after passing through the tunnel, quick communication recovery can be performed when the tunnel mode is used to pass through the tunnel.

  FIG. 5 is a diagram illustrating an example of a system configuration of the mobile phone 108. The cellular phone 108 includes a transmission / reception unit 601, a control unit 602, and a signal processing unit 603. The transmission / reception unit 601 is a block that communicates with the base station. The control unit 602 is a block that controls method selection from position information, speed information, and tunnel information, and a method selection unit 604 that performs method selection of a mobile phone, and mode selection that notifies a method selection switching condition to the method selection unit. Part 610. The signal processing unit 603 is a block that processes a signal input / output from the transmission / reception unit 601.

  The out-of-service determining unit 607 determines whether the received radio wave in the transmission / reception unit 601 is out of service. The mobile phone 108 receives a signal called a pilot signal, which is a signal for synchronization, transmitted from the base station, and determines which base station can communicate with it. When the reception level of the pilot signal exchanged between the mobile phone 108 and the base station becomes lower than a predetermined value, the out-of-service determining unit 607 determines that the mobile phone is out of service.

  The reception signal processing unit 606 decodes the signal received by the transmission / reception unit 601 and passes the decoded information and communication data to the broadcast information acquisition unit 608 and the data reception unit 613. The data receiving unit 613 processes communication data obtained from the received signal processing unit 606. Here, since the processing of communication data is the same as that of a general mobile phone, description thereof is omitted. The broadcast information acquisition unit 608 determines whether broadcast information is included from the signal processed by the received signal processing unit 606, and if so, acquires and holds the broadcast information portion of the base station. To do.

  The tunnel information acquisition unit 609 determines whether or not the tunnel information is included in the broadcast information acquired from the broadcast information acquisition unit 608. If the tunnel information is included, the tunnel information acquisition unit 609 acquires and holds the tunnel information. The position information acquisition unit 611 acquires and holds the position information of the mobile phone 108 using a measurement function such as GPS built in the mobile phone 108. The speed information acquisition unit 612 holds the measured speed information by, for example, determining the moving speed of the mobile phone from the position information acquired by the position information acquisition unit 611. The position information acquisition unit 611 and the speed information acquisition unit 612 may start or stop measurement according to an instruction from the tunnel information acquisition unit 609.

  The mode selection unit 610 includes position information held by the position information acquisition unit 611, position information on the entrance / exit of the tunnel held by the tunnel information acquisition unit 609, and speed information held by the speed information acquisition unit 612. Based on the above, the method selection unit 604 is notified of whether the mode selection is performed in the normal mode or the tunnel mode. Upon receiving the out-of-service notification from the out-of-service determining unit 607, the method selecting unit 604 acquires the mode selection mode from the mode selecting unit 610, and performs the method selection accordingly.

  At the time of data transmission, transmission data is given from the block (not shown) to the data transmission unit 614, the transmission signal processing unit 605 performs encoding according to the communication standard being used, and radio waves are transmitted from the transmission / reception unit 601. Since these data transmission processes are the same as those of a general mobile phone, description thereof will be omitted.

  FIG. 6 is a diagram illustrating an example of a system configuration of the base stations 104 and 106. The base stations 104 and 106 include a wireless signal transmission / reception unit 801, a signal processing unit 802, and a wired interface 809. The wireless signal transmission / reception unit 801 is a block that performs communication with a mobile phone, and the wired interface 809 is connected to a communication network on the backhaul side (not shown), and exchanges information with the communication network on the backhaul side. It is a block. The signal processing unit 802 is a block that processes a signal input / output from the wireless signal transmission / reception unit 801 or the wired interface 809.

  The reception signal processing unit 803 decodes signals received by the base stations 104 and 106 through the wireless signal transmission / reception unit 801. The data portion of the signal decoded by the reception signal processing unit 803 is acquired by the data reception unit 805, arranged for each data destination, and transferred to the communication network on the backhaul side via the wired interface 809. Communication data sent from the backhaul side communication network is provided to the data transmission unit 806 via the wired interface 809, and is organized for each mobile phone of the transmission destination.

  The transmission signal processing unit 804 integrates the information of the data transmission unit 806 and the notification information processing unit 807, encodes the information according to the communication standard, and transmits the information from the wireless signal transmission / reception unit 801 to each mobile phone. The broadcast information processing unit 807 is a block that creates broadcast information that the base stations 104 and 106 periodically broadcast. The tunnel information holding unit 808 is a block that holds position information of tunnels included in the communication areas 105 and 107 of the base stations 104 and 106. Tunnel information is set in advance for each of the base stations 104 and 106 by a maintenance person. Also, the content of the broadcast information and the tunnel information are updated from the communication network on the backhaul side, reflecting the situation around the base stations 104 and 106.

  If tunnel information is stored in the tunnel information holding unit 808, the broadcast information processing unit 807 creates the broadcast information of the base station by including the tunnel information in the content of the broadcast information and provides it to the transmission signal processing unit 804. The notification information processing unit 807 may include tunnel information in the content of the notification information in the form of information that does not affect a general mobile phone other than the mobile phone 108, and the radio signal transmission / reception unit 801 You may make a call to a mobile phone. Further, the base station 102 that is not a base station near the tunnel also includes the tunnel information holding unit 808 as in the base stations 104 and 106, and does not have to hold the tunnel information. The base station 102 does not need to hold the tunnel information holding unit 808. The configuration other than the tunnel information holding unit 808 may be the same as that of the base stations 104 and 106.

  FIG. 7 is a sequence diagram illustrating an example of measurement switching control of position / speed information of the mobile phone 108. The operation in which the mobile phone 108 switches the measurement of the position / speed information regarding the presence / absence of tunnel information will be described with reference to the sequence diagram of FIG. The mobile phone 108 moves between the communication areas and determines whether or not the notification from the base station has been received (S2). When the notification information acquisition unit 608 of the mobile phone 108 determines that the notification is not received, the determination is repeated, and when it is determined that the notification is received in the communication areas 103, 104, 107, etc., whether the notification information includes tunnel information. The process proceeds to determination by the tunnel information acquisition unit 609 (S3).

  When the mobile phone 108 enters the communication areas 105 and 107 and the tunnel information acquisition unit 609 determines that tunnel information is included in the received notification information, the mobile phone 108 receives the position / speed information. Is started (S3, S5). When the mobile phone 108 enters the communication area 103 or the like and the tunnel information acquisition unit 609 determines that the tunnel information is not included in the notification information, the mobile phone 108 measures the position / speed information. Stop (S3, S4). In this way, the mobile phone 108 continues to receive the notification from the base station as the communication area moves, and switches the measurement of the position / speed information according to the notification information.

  Note that the tunnel information acquisition unit 609 may hold the tunnel information included in the broadcast information in S3. Here, when the tunnel information with the same content is already held, it may be overwritten with the same content, or it may be determined that the content is the same and the tunnel information included in the broadcast information may be discarded. . Further, the tunnel information acquisition unit 609 may delete the held tunnel information in S4. As a result, the amount of tunnel information held can be reduced.

  FIG. 8 is a sequence diagram illustrating an example of mode selection mode switching control of the mobile phone 108. The position / speed information switching control described with reference to FIG. 7 and the mode switching control described with reference to FIG. 8 are performed in parallel. An operation in which the mobile phone 108 performs tunnel determination and selects a mode corresponding to the situation will be described with reference to the sequence diagram.

  When the mobile phone 108 detects an out-of-service state by the out-of-service determining unit 607 (S22), the mobile phone 108 determines whether the tunnel information acquisition unit 609 holds the tunnel information acquired from the notification information (S23). If the tunnel information is retained, the mobile phone 108 next detects the position of the mobile phone 108 measured immediately before out of service area and the tunnel entrance closest to the mobile phone 108 position among the tunnels included in the tunnel information. The mode selection unit 610 determines whether the position is equal to or less than a certain distance, for example, a threshold value of 50 meters or less (S24).

  If the mobile phone 108 is less than a certain distance from the entrance of the tunnel, the mobile phone 108 sets whether its own speed information measured immediately before out of service is above a certain speed, for example, a threshold speed of 30 kilometers or more. The selection unit 610 determines (S25). When all the conditions are satisfied in the determinations in S23 to 25, in the mobile phone 108, the mode selection unit 610 sets the mode to the tunnel mode (S26), and the method selection unit 604 performs method selection (S29). If even one of the conditions is not satisfied, in the mobile phone 108, the mode selection unit 610 enters the mode normal mode (S27), and the method selection unit 604 performs the method selection (S29).

  If the method is selected and the out-of-service determining unit 607 detects the in-service state, the mobile phone 108 returns to S21 again. If the out-of-range determination unit 607 does not detect the out-of-service state even after the method selection, the mobile phone 108 waits for the sleep time according to each mode under the control of the method selection unit 604 (S28), and performs the method selection again. (S29). The threshold of 50 meters or 30 kilometers per hour may be set in advance from an input unit (not shown) or may be set using information included in the received radio wave.

  With this configuration, only when the mobile phone enters the tunnel and goes out of service, it can function so as not to reduce the frequency of method selection, and communication can be quickly recovered after passing through the tunnel. In addition, for example, when it is out of service area other than entering the tunnel, such as work in a basement, power consumption can be suppressed by reducing the frequency of method selection. In this way, it is possible to ensure both user convenience and reduced power consumption.

  In the second embodiment, a process for controlling the frequency of method selection using the tunnel length and reducing power consumption in passing through the tunnel will be described. Also in the second embodiment, the relationship between the tunnel, the base station, and the mobile phone is the same as the system configuration described with reference to FIG. 1, but the base station is different from that described later with reference to FIG. The difference will be described later with reference to FIG.

  FIG. 9 is a diagram illustrating an example of tunnel information broadcasted by a base station near the tunnel. The tunnel information is held at least by the base station and notified to the mobile phone, and includes tunnel length information in addition to the tunnel ID and the position information of the entrance / exit of the tunnel. The tunnel length information is information for predicting the timing when the mobile phone finishes passing through the tunnel based on its moving speed. The length information of the tunnel is not necessarily the actual length of the tunnel, but may be a virtual length for predicting the exact timing of the end of the tunnel passage based on the gradient in the tunnel or the like.

  FIG. 10 is a diagram illustrating an example of the relationship between the method selection time and frequency in the normal mode and the relationship between the method selection time and frequency in the tunnel mode. The vertical axis in the figure represents the timing of system selection, and the horizontal axis represents the elapsed time since the mobile phone was out of service. The normal mode shown in FIG. 10 is the same as the normal mode described with reference to FIG.

  In the tunnel mode, the mobile phone keeps the frequency of method selection low until the predicted tunnel passage time t6 predicted from the tunnel length information. As a result, it is possible to suppress wasteful method selection while passing through the tunnel and reduce the power consumption of the mobile phone. Note that the method selection interval until the predicted tunnel passage time t6 may be a3, for example, or may be a value obtained by dividing the predicted tunnel passage time t6 by a preset value.

  The predicted tunnel passage time t6 is calculated by dividing the length of the tunnel by the speed of the mobile phone immediately before entering the tunnel. Further, a margin may be provided by subtracting a preset value from the divided value. After the tunnel passage estimated time t6, the same method selection as in the normal mode is performed thereafter. This makes it possible to quickly restore communication by increasing the frequency of method selection at the timing of moving to the in-zone state after passing through the tunnel.

  FIG. 11 is a diagram illustrating an example of a relationship of communication recovery timing after passing through the tunnel using each of the normal mode and the tunnel mode. When passing through the tunnel using the normal mode immediately after out of service area, the timing is the same as described with reference to FIG. When the tunnel mode is used to pass through the tunnel, when the time t6 at which the tunnel is expected to pass has elapsed, the mode selection is switched to the same mode selection as in the normal mode.

  When the same method selection as in the normal mode is performed, communication is restored at time t9 when the method selection is performed for the first time after passing through the tunnel. At this time, if the method selection frequency shown in FIG. 10 falls before time t7, the expected value of the time from passing through the tunnel to communication recovery is a0 / 2. On the other hand, when selecting a method using the normal mode, the expected value of the time from the passage through the tunnel to the communication recovery is a3 / 2 as already described. As described above, since it takes a long time to select a method after passing through the tunnel, quick communication recovery can be performed when the tunnel mode is used to pass through the tunnel.

  FIG. 12 is a diagram illustrating an example of a system configuration of a mobile phone. Portions to which the same reference numerals as those in FIG. 7 are given are the same as those in FIG. 7, and thus description thereof is omitted here. The passage timing prediction unit 701 calculates the time required for the mobile phone to pass through the tunnel from the tunnel information acquired by the tunnel information acquisition unit 609 and the speed information held by the speed information acquisition unit 612, and sends it to the method selection unit 604. It is a block to notify. The estimated tunnel passage time is calculated by dividing the length of the tunnel by the speed of the mobile phone immediately before entering the tunnel. The method selection unit 604 uses the tunnel passage prediction time obtained from the passage timing prediction unit 701 to select a method as in the tunnel mode described with reference to FIGS.

  Further, the length information of the tunnel may be fed back by notifying the base station of time and speed information required for actual passage after the mobile phone has passed through the tunnel. For example, the mobile phone notifies the base station of the time and speed information required for the actual passage, and transfers the base station close to the entrance of the tunnel between the base stations. The base station close to the entrance is transferred the transferred time. The length information of the tunnel may be calculated by dividing by the determined speed. Also, the base station near the exit notifies the base station near the entrance of the time when the base station exits the mobile phone tunnel and the identification information of the mobile phone, and the base station near the entrance has the same identification information as the notified identification information. The time required for actual passage may be calculated from the difference from the time when the vehicle entered the tunnel. Such feedback may improve the accuracy of the tunnel length information of the base station.

  Thus, the mobile phone can increase the frequency of method selection in accordance with the timing of exiting the tunnel, and can realize quick communication recovery after passing through the tunnel. Furthermore, since the frequency of method selection is kept low while passing through the tunnel, the power consumption of the mobile phone can be greatly reduced.

  In the above explanation, the explanation was mainly based on LTE technology, but any communication method in which the base station broadcasts is applicable, so HRPD (High Rate Packet Data), WiMAX (registered trademark, Worldwide Interoperability for Microwave) Access), GSM (registered trademark, Global System for Mobile Communications), etc., and can be applied to all wireless technologies using a general wireless system. These wireless technologies have a method of selecting a method, and it is necessary to satisfy both the power consumption of the mobile phone and the convenience of the user for quick communication recovery from the out-of-service state, so that the effects described above can be obtained. .

101: tunnel 102, 104, 105: base station 103, 105, 107: communication area 108: mobile phone 604: method selection unit 608: broadcast information acquisition unit 609: tunnel information acquisition unit 610: mode selection unit 611: acquisition of position information Unit 612: Speed information acquisition unit 701: Passing timing prediction unit 807: Notification information processing unit 808: Tunnel information holding unit

Claims (14)

A mobile phone that communicates wirelessly with a base station,
A tunnel information acquisition unit for acquiring tunnel information from the base station;
A location information acquisition unit for acquiring location information of the mobile phone;
Based on the tunnel information and the position information, a mode selection unit that selects one mode from a plurality of modes of wireless communication method selection;
A mobile phone comprising: a method selection unit that performs method selection of the wireless communication based on the selected mode. The mobile phone according to claim 1,
Based on the state of the wireless communication with the base station, further comprising an out-of-service determination unit that determines that the service is out of service,
The mode selection unit selects one mode from a plurality of modes having different execution intervals of the wireless communication method selection based on the tunnel information and the position information,
When the out-of-service determining unit determines that the out-of-service determining unit is out of the service area, the method selecting unit controls the wireless communication method selection execution interval based on the selected mode, and executes the wireless communication method selection. A cellular phone characterized by controlling to a sleep state during a period when it is not. The mobile phone according to claim 2,
A speed information acquisition unit that calculates and acquires speed information of the mobile phone based on the position information;
The mode selection unit selects one mode from a plurality of modes having different execution intervals of the wireless communication method selection based on the tunnel information, the position information, and the speed information. . The mobile phone according to claim 3,
The mode selection unit determines that the distance between the position of the entrance / exit of the tunnel included in the tunnel information and the position of the position information is equal to or less than a preset first threshold, and the speed of the speed information is A mobile phone characterized in that it is determined to be equal to or greater than a preset second threshold value, and a mode in which the execution interval of the wireless communication method selection is narrower than other modes is selected. The mobile phone according to claim 4,
The mode selection unit determines that the distance between the position of the entrance / exit of the tunnel included in the tunnel information and the position of the position information is greater than the first threshold, or the speed of the speed information is the second speed. The mobile phone is characterized in that the mode is determined to be less than a threshold value, and a mode in which the execution interval of the wireless communication method selection is wider than in other modes is selected. The mobile phone according to claim 5, wherein
The mobile phone according to claim 1, wherein the tunnel information acquisition unit acquires the tunnel information from broadcast information of the radio base station. A mobile phone that communicates wirelessly with a base station,
A tunnel information acquisition unit for acquiring tunnel information from the base station;
A location information acquisition unit for acquiring location information of the mobile phone;
Based on the position information, a speed information acquisition unit that acquires a moving speed of the mobile phone;
Based on the tunnel information and the moving speed, a passage timing prediction unit that predicts a tunnel passage time of the mobile phone,
Based on the tunnel information and the position information, a mode selection unit that selects one mode from a plurality of modes of wireless communication method selection;
When the selected mode is the first mode, the wireless communication method selection is performed based on the first mode, and when the selected mode is the second mode, the second mode A mobile phone comprising: a method selection unit that performs method selection of the wireless communication based on the tunnel transit time. The mobile phone according to claim 7, wherein
When the selected mode is the first mode, the method selection unit widens the execution interval of the method selection of the radio signal based on the first mode, and the selected mode is the second mode. In the case of the mode, based on the second mode and the tunnel transit time, the execution interval of the wireless communication method selection is narrowed, and the sleep mode is controlled during the period when the wireless communication method selection is not executed. A featured mobile phone. The mobile phone according to claim 8, wherein
When the selected mode is the second mode, the method selection unit narrows the method selection execution interval when the tunnel passage time elapses. The mobile phone according to claim 9, wherein
The mobile phone according to claim 1, wherein the passage timing prediction unit predicts the tunnel passage time by dividing a tunnel length included in the tunnel information by the moving speed. The mobile phone according to claim 10, wherein
The mobile phone according to claim 1, wherein the tunnel information acquisition unit acquires the tunnel information from broadcast information of the radio base station. A wireless communication system,
A first base station that has a first communication area capable of wireless communication and broadcasts tunnel information;
A second base station having a second communication area capable of wireless communication and not informing tunnel information;
In the first communication area, a tunnel information acquisition unit that acquires the tunnel information broadcast by the first base station, a position information acquisition unit that acquires its own location information, the tunnel information, and the location information A mode selection unit that selects one mode from among a plurality of modes of the wireless communication method selection, and a method selection unit that executes the wireless communication method selection based on the selected mode. A wireless communication system comprising a mobile phone. The wireless communication system according to claim 12, comprising:
The mobile phone further includes an out-of-service determination unit that determines that the mobile phone is out of service based on the state of the wireless communication with the first base station and the second base station,
The mode selection unit selects one mode from a plurality of modes having different execution intervals of the wireless communication method selection based on the tunnel information notified by the first base station and the position information,
When the out-of-service determining unit determines that the out-of-service determining unit is out of the service area, the method selecting unit controls the wireless communication method selection execution interval based on the selected mode, and executes the wireless communication method selection. A wireless communication system, wherein the wireless communication system is controlled to a sleep state during a period when it is not. The wireless communication system according to claim 13, comprising:
If the tunnel information acquisition unit does not acquire the tunnel information in the second communication area, the tunnel information acquisition unit stops the position information acquisition unit, and if the out-of-range determination unit determines that the out-of-range is out of the range, A wireless communication system, wherein the mode selection unit is controlled to select a mode in which an execution interval of method selection is wider than other modes.

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