JP5498351B2 - Base station and base station control method - Google Patents

Description

  The present invention relates to a base station and a base station control method, and more particularly to a femtocell base station connected to a mobile communication network via a general line and a femtocell base station control method.

  In recent years, in mobile communication systems, a base station scheme called a femto cell (FemtoCell) that covers a very small area compared to a conventional macro cell base station (wide area base station) has been proposed. A femtocell base station is a small base station installed in a house or a small office, for example, and a cell of a conventional mobile phone, that is, an area covered by one macrocell base station is about 1 to several kilometers in radius. On the other hand, the area covered by the femtocell base station is about several meters to several tens of meters. The femtocell base station is connected to a mobile communication network via a general line (a broadband line such as ADSL) drawn into each home. Since general lines are generally popular as access lines, even users who are outside the area of the macro cell base station can use the same cellular phone service as the macro cell base station (call, mail function, SMS (Short Message Service)) if there is a broadband line. , WEB browsing, etc.) can be used inexpensively and easily. Furthermore, as a telecommunications carrier, it is not necessary to use the resources (bandwidth, etc.) of the existing macrocell base station that should have been consumed by using the femtocell base station and the broadband line. There is an advantage that the area can be improved.

  By the way, the femtocell base station continues to send out the broadcast channel even when there is no mobile device using the own station within the communicable range (within the service area). For example, in a situation where a mobile device user goes to work or school during the day and there is no user in the home where the femtocell base station is installed, the femtocell base station Continuing to transmit radio waves is a waste of power. In response to such a problem, in Patent Document 1, when there is no communication within a certain period of time, the transmission function of the base station is stopped, and when the mobile station makes a call during this period, the mobile station transmits to the base station. In response to this, the base station transmits a transmission activation request signal, and the base station receives this signal and restarts the transmission function to enable communication with the mobile device. Something to reduce has been proposed.

JP 2002-152129 A

  However, in the technique disclosed in Patent Document 1 described above, when a mobile station makes a call, the base station waits for a transmission activation request signal transmitted from the terminal station, and performs synchronization confirmation and self-base station zone confirmation. Therefore, it takes time to establish a communication connection as compared with the conventional method. Therefore, this technology is effective in the case of a system in which calls are normally generated at a low frequency or a system in which the frequency of connection is significantly reduced, but many mobile devices can communicate with the base station. In a system that moves outside the area, a method for more efficiently reducing power consumption is required.

  An object of the present invention made in view of such a point is to provide a base station and a control method of the base station that efficiently reduce power consumption.

The invention of the base station according to the first aspect of achieving the above object is as follows:
A wireless communication unit that communicates with a mobile device using its own station;
An acquisition unit that acquires location information and ON / OFF information of a mobile device that uses the local station from the management server;
Compare the acquired location information of the mobile device and the location information of its own station, determine whether the mobile device is in a communicable range, all mobile devices are out of the communicable range, and all A control unit that stops wireless communication when the mobile device is powered on;
It is characterized by providing.

The invention of the base station according to the second aspect is as follows:
The control unit stops the wireless communication, and starts wireless communication when at least one mobile device exists within a communicable area.

The invention of the base station according to the third aspect is as follows:
The control unit stops the wireless communication, and starts wireless communication when power of at least one mobile device is OFF.

Invention of the control method of the base station of the mobile communication system according to the fourth aspect
Communicating with a mobile device using the own station;
Obtaining the location information and ON / OFF information of the mobile device using the own station from the management server;
Comparing the acquired location information of the mobile device with the location information of the own station;
Determining whether or not the mobile device is within a communicable area, stopping all wireless communication when all mobile devices are outside the communicable range and all mobile devices are powered; and
Starting at least one mobile device in a communicable area, or starting wireless communication when at least one mobile device is powered off;
It is characterized by including.

  According to the present invention, it is possible to provide a base station and a base station control method that efficiently reduce power consumption.

1 is a schematic configuration diagram of a mobile communication system including a femto cell and a macro cell. It is a schematic block diagram of a femtocell base station. It is a flowchart which shows the process which stops transmission of the alerting | reporting channel of a femtocell base station. It is a flowchart which shows the process which starts transmission of the alerting | reporting channel of a femtocell base station.

  Embodiments of a base station and a base station control method according to the present invention will be described below with reference to the drawings. In the following description, CDMA2000 1xEV-DO is assumed as a mobile communication system, but the present invention is not limited to this.

FIG. 1 is a schematic configuration diagram of a mobile communication system including a femto cell and a macro cell.
The mobile communication system 100 includes a management server SRV, a network NET, a macro cell base station AN, a femto cell base station FAP, and a plurality of mobile devices (wireless communication terminals) AT1 and AT2. The mobile devices AT1 and AT2 are registered in advance so that the femtocell base station FAP can be used. The management server SRV is connected to the macrocell base station AN and the femtocell base station FAP via the network NET. The management server SRV has location information of the mobile devices AT1 and AT2 and information regarding whether the mobile devices AT1 and AT2 are turned on or off (hereinafter referred to as “ON / OFF information”). Each time the mobile devices AT1 and AT2 perform handover between base stations (for example, between the femtocell base station FAP and the macrocell base station AN) and when the power is switched from OFF to ON, the location information and ON / OFF information is notified to the management server SRV. Further, the mobile devices AT1 and AT2 regularly notify the management server SRV of ON / OFF information outside the above case. The ON / OFF information may be information indicating whether the mobile device is communicating with any of the base stations (ON) or not communicating with any of the base stations (OFF).

  In the case of the illustrated example, since the mobile device AT1 exists in the communicable range FAPs of the femtocell base station FAP, the mobile device AT1 notifies the management server SRV of the location information and the ON / OFF information via the femtocell base station FAP. Since the mobile device AT2 exists outside the communicable range of the femtocell base station FAP and within the communicable range ANs of the macrocell base station AN, the mobile device AT2 notifies the management server SRV of the location information via the macrocell base station AN. Note that the location information of the mobile devices AT1 and AT2 may be information acquired from the GPS or the like instead of the location information via the base station (information indicating whether the mobile station is within the communicable range of the base station). it can.

  Next, the femtocell base station FAP will be described. FIG. 2 shows a schematic block diagram of the femtocell base station FAP. The femtocell base station FAP includes an antenna ANT, a control unit 110, a wireless communication unit 120, an acquisition unit 130, a storage unit 140, and a wired communication unit 150. The control unit 110 controls the entire femtocell base station FAP. The radio communication unit 120 transmits and receives radio waves for communicating with the mobile devices AT1 and AT2 via the antenna ANT. The broadcast channel is also transmitted. The broadcast channel is a channel that is periodically transmitted from the femtocell base station FAP, and is a common channel for broadcasting common information to all the mobile devices AT1 and AT2. The acquisition unit 130 acquires, from the management server SRV, the location information of the mobile devices AT1 and AT2 that use the local station and the ON / OFF information of the mobile devices AT1 and AT2. The storage unit 140 stores registration information of the mobile devices AT1 and AT2 that use the own station (the femtocell base station FAP is installed in a home, for example, and the mobile devices AT1 and AT2 that use the own station are registered in advance), Various setting information such as the position information of the own station is stored. The wired communication unit 150 is connected to a network NET such as the Internet via a router or a general line (a broadband line such as ADSL).

  Next, processing of the femtocell base station FAP will be described using FIG. 3 and FIG. FIG. 3 is a flowchart showing a process of stopping transmission of the broadcast channel of the femtocell base station. At the start, the radio communication unit 120 of the femtocell base station FAP is in a state of transmitting a broadcast channel. Periodically, the acquisition unit 130 acquires the location information and ON / OFF information of all the mobile devices AT1 and AT2 that use the local station from the management server SRV (step S101). The control unit 110 compares the acquired location information of the mobile devices AT1 and AT2 with the location information of its own station, and determines whether or not the mobile devices AT1 and AT2 exist in the communicable range FAPs (step S102). When all the mobile devices AT1 and AT2 exist outside the communicable area (in the case of YES), the control unit 110 advances the processing to step S103. The control unit 110 determines whether or not the power of the acquired mobile devices AT1 and AT2 is ON (step S103). When the power of all the mobile devices AT1 and AT2 is ON (in the case of YES), the control unit 110 advances the process to step S104. Control unit 110 stops broadcasting the broadcast channel (step S104) and ends the process. In step S102, when at least one mobile device AT1 or AT2 is present in the communicable FAPs (in the case of NO), and in step S103, at least one mobile device AT1 or AT2 is turned off. In the case (NO), the control unit 110 ends the process.

  FIG. 4 is a flowchart showing processing for starting transmission of a broadcast channel of the femtocell base station. At the start, the radio communication unit 120 of the femtocell base station FAP is in a state of not sending out a broadcast channel. Periodically, the acquisition unit 130 acquires the location information and ON / OFF information of all the mobile devices AT1 and AT2 that use the local station from the management server SRV (step S201). The controller 110 determines whether or not the power of the acquired mobile devices AT1 and AT2 is ON (step S202). When the power of all the mobile devices AT1 and AT2 is ON (in the case of NO), the control unit 110 advances the process to step S203. The control unit 110 compares the acquired location information of the mobile devices AT1 and AT2 with the location information of its own station, and determines whether or not the mobile devices AT1 and AT2 exist in the communicable range FAPs (step S203). When all the mobile devices AT1 and AT2 exist outside the communicable range (in the case of NO), the control unit 110 ends the process without starting to send out the broadcast channel. In step S202, when at least one mobile device AT1 and AT2 is powered off (in the case of YES), and in step S203, at least one mobile device AT1 and AT2 are present in the communicable FAPs ( In the case of YES), control unit 110 starts transmission of the broadcast channel (step S204) and ends the process. Note that when the mobile devices AT1 and AT2 are powered off, the contents of the location information of the mobile devices AT1 and AT2 are unknown, so the control unit 110 starts sending out the broadcast channel.

  It is determined whether or not the mobile devices AT1 and AT2 that use the mobile station exist in the communicable range FAPs of the femtocell base station FAP when all the mobile devices AT1 and AT2 are outside the communicable range. This is to reduce wasteful power consumption by stopping transmission of the broadcast channel. In the above-described embodiment, the broadcast channel has been described as an example. However, the present invention is not limited to this, and the radio communication of the femtocell base station FAP can be stopped.

  Further, the femtocell base station FAP determines whether or not the mobile devices AT1 and AT2 that use the own station are turned on for the following reason. Consider a case where the femtocell base station FAP does not acquire ON / OFF information of the mobile devices AT1 and AT2 from the management server SRV. When the mobile device AT1 exists outside the communicable area of the femtocell base station FAP, the mobile device AT1 notifies the management server SRV of location information via the macrocell base station AN. The femtocell base station FAP acquires the location information of the mobile device AT1 from the management server SRV, and grasps that the mobile device AT1 is outside the communicable range of the femtocell base station FAP. Then, the femtocell base station FAP determines that all the mobile devices AT1 and AT2 exist outside the communicable area, and stops sending the broadcast channel. Next, it is assumed that the mobile device AT1 turns the power supply from ON to OFF, moves to the communicable range FAPs of the femtocell base station FAP, and then turns the power supply from OFF to ON. At this time, since the femtocell base station FAP has stopped sending the broadcast channel, the mobile device AT1 does not recognize that it is within the communicable range FAPs of the femtocell base station FAP and passes through the macrocell base station AN. Thus, communication is performed. As described above, if the femtocell base station FAP does not obtain the ON / OFF information of the mobile devices AT1 and AT2 from the management server SRV, the mobile device AT1 existing in the communicable range FAPs of the femtocell base station FAP There arises a problem of performing communication without going through the station FAP. On the other hand, in the present invention, when the mobile device AT1 turns the power supply from ON to OFF, the femtocell base station FAP starts sending out the broadcast channel. Therefore, after the mobile device AT1 moves to the communicable range FAPs of the femtocell base station FAP and then turns the power source from OFF to ON, the mobile device AT1 communicates via the femtocell base station FAP. Can do. That is, the femtocell base station FAP determines whether or not the mobile devices AT1 and AT2 that use its own station are powered on because the mobile device AT1 exists in the communicable range FAPs of the femtocell base station FAP. In this case, the communication is surely performed via the femtocell base station FAP to enable high-quality communication.

  As described above, in the present invention, the femtocell base station FAP grasps the location information and ON / OFF information of the mobile devices AT1 and AT2 that use the own station and stops the wireless communication, thereby reducing power consumption. Can be realized efficiently.

DESCRIPTION OF SYMBOLS 100 Mobile communication system 110 Control part 120 Wireless communication part 130 Acquisition part 140 Storage part 142 Registered terminal number determination part 150 Wired communication part ANT Antenna AN Macrocell base station ANs The communicable range FAP femtocell base station FAPs femto of macrocell base station AN NET network SRV management server AT1, AT2 within communication range of cell base station FAP

Claims (4)

A wireless communication unit that communicates with a mobile device using its own station;
An acquisition unit that acquires location information and ON / OFF information of a mobile device that uses the local station from the management server;
Compare the acquired location information of the mobile device and the location information of its own station, determine whether the mobile device is in a communicable range, all mobile devices are out of the communicable range, and all A control unit that stops wireless communication when the mobile device is powered on;
A base station comprising:   The base station according to claim 1, wherein the control unit stops the wireless communication, and starts wireless communication when at least one mobile device exists within a communicable area.   The base station according to claim 1, wherein the control unit stops the wireless communication and starts wireless communication when power of at least one mobile device is OFF. A control method for a base station of a mobile communication system, comprising:
Communicating with a mobile device using the own station;
Obtaining the location information and ON / OFF information of the mobile device using the own station from the management server;
Comparing the acquired location information of the mobile device with the location information of the own station;
Determining whether or not the mobile device is within a communicable area, stopping all wireless communication when all mobile devices are outside the communicable range and all mobile devices are powered; and
Starting at least one mobile device in a communicable area, or starting wireless communication when at least one mobile device is powered off;
A control method for a base station.

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