WO2010082285A2 - Wireless communication system, mobile communication terminal and communication connection method - Google Patents

Abstract

In order to perform connection processing by suitably selecting a different base station in the range in which communication is possible, in accordance with the condition of a mobile communication terminal, a wireless communication system includes: a plurality of mobile communication terminals; a first base station capable of wireless communication with a mobile communication terminal in a wideband communication service area; and a second base station capable of wireless communication with a mobile communication terminal in a specified communication service area. The mobile communication terminals include: an information section that stores base station information for distinguishing between the second base station and the first base station and for further identifying the second base station; and a control section that compares the base station information delivered from the first or second base station and the base station information stored in the information section. If the comparison results coincide, the mobile communication terminals implement a process for transferring to the base station.

Description

Wireless communication system, mobile communication terminal, and communication connection method

The present invention relates to a wireless communication system, a mobile communication terminal, and a communication connection method.
This application claims priority based on Japanese Patent Application No. 2009-006405 filed in Japan on January 15, 2009, the contents of which are incorporated herein by reference.

Currently, mobile phone services are widely used and used by many people. Such mobile phone operators can cover a necessary service area by installing a large number of base stations called macrocells having a communication service area with a radius of several hundred meters to several kilometers. It provides various services such as voice calls, videophone calls, and packet communication. However, it is difficult to completely cover the entire service area with only the macro cell, and there are places with weak electric fields near the boundary of the macro cell and in places where radio waves are difficult to reach such as indoors. Symptoms such as inability to obtain communication speed and unstable call voice quality occur. In order to prevent such a symptom from occurring, a base station called a femto cell having a specific communication service area with a radius of about several tens of meters has been studied. Unlike a conventional base station, the femtocell is connected to a core network installed by a provider using, for example, a broadband line installed by a user in each home.

When such a connection is made, the communication cost can be reduced by using a broadband line, thereby reducing the burden on the operator side and using a macro cell. In addition, the femtocell assumes that the number of users is limited to a small number of users permitted by the user who installed the femtocell, and the femtocell can be occupied by a small number of terminals. Can be ensured (see, for example, Patent Documents 1 and 2).

JP 2005-109570 A Special table 2007-534227

In the future, when femtocells capable of high-speed communication at low cost become available, it is conceivable that users will actively use them and a large number of femtocells will be installed. The femtocell's communicable range is originally intended to serve only a limited range such as in a home or small store, but when providing a stable and high-speed service, the end of the house When installed so as to satisfy the conditions, the femtocell radio waves can be received even outdoors.

As described above, the femtocell is allowed to connect only to a specific user, but in order to determine whether the femtocell is a terminal that can be connected on the femtocell side, the mobile communication terminal receives the reception quality of the femtocell. Is good, there is a possibility that processing for performing connection to the femto cell is performed, and the operation of being rejected by the base station and maintaining the connection with the original macro cell may be repeated. Or even if it is a case where it is notified by the broadcast information of the femtocell that it is a femtocell, since the process of the femtocell transition is started, the result of acquiring the broadcast destination broadcast information is a femtocell And the operation of connecting to the original macro cell is repeated again. Particularly in an environment such as a condominium or an apartment where a very large number of households are adjacent to each other, for example, when the user moves through the corridor, the base station shift process is frequently repeated. When such a process is repeated, there is a problem that the processing load of the mobile communication terminal increases, the power consumption increases, and the waiting time is shortened.

In addition, since the base station transition process is executed depending on the reception quality of each base station measured by the mobile communication terminal, even if it enters the service area of the femtocell to which the user can connect, the reception quality of the macro cell If it does not improve, there is a problem that it is not possible to connect to the target femtocell. For example, when used near a doorway or near a window, the reception quality of a macro cell may be better, but in this case, it is a service area of a femto cell and there is reception quality for stable communication. In addition, communication may occur in the macro cell. If you are in a femtocell, you may be able to communicate at low cost using a broadband line. If you are in a femtocell service area, you will be connected to the femtocell as much as possible. It is desirable.

The present invention has been made in view of such circumstances, and a radio communication system capable of appropriately selecting a base station having a different communicable range and performing connection processing according to the situation of a mobile communication terminal, mobile An object is to provide a communication terminal and a communication connection method.

The present invention includes a plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area. A mobile communication terminal comprising: a second base station capable of performing the operation, wherein the mobile communication terminal distinguishes the second base station from the first base station; and An information unit for storing base station information for further specifying two base stations is compared with the base station information stored in the information unit for the base station information transmitted from the first or second base station. And a control unit that performs base station transition processing if the comparison results match.

The present invention is characterized in that the mobile communication terminal performs a transition process to the second base station without depending on communication quality with the individual base station.

The present invention includes a plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area. A mobile communication terminal comprising: a second base station capable of performing the operation, wherein the mobile communication terminal distinguishes the second base station from the first base station; and Base station information for further specifying two base stations, an information unit for storing base station information to which a base station search priority is assigned, and a base station having a higher base station search priority in order. And a determination unit that determines whether or not connection is possible.

In the present invention, the mobile communication terminal performs a transition process to the second base station having the highest priority among the second base stations detected without depending on the communication quality with the second base station. It is characterized by that.

The present invention includes a plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area. A wireless communication system comprising: a second base station capable of performing a first base station; and a core network that manages the first base station, the second base station, and the mobile communication terminal in the previous period, Holds information on a second base station connectable to each mobile communication terminal and information on whether the connectable second base station is included in the communication service area of the first base station. When the mobile communication terminal moves into the communication service area of the second base station included in the communication service area of the first base station, or out of the communication service area When moved, the mobile communication terminal has moved into the communication service area of the second base station via the first base station, or moved out of the communication service area. The mobile communication terminal performs the transition process to the second base station only in the communication service area in which the second base station is included in the communication service area of the first base station. It is characterized by that.

The present invention provides a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and a first base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area. A mobile communication terminal apparatus used in a wireless communication system including two base stations, and holds base station information for specifying the second base station, and the detected base station is the second base station In such a case, a transition process for connecting to the second base station is performed only when the information matches the held base station information.

The present invention provides a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and a first base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area. A mobile communication terminal apparatus used in a wireless communication system comprising two base stations, wherein the second base station priorities are determined according to limited connection conditions, and the second base station that can be connected; and When detecting the first base station or the second base station, the base station information specifying the second base station is detected, and the second base station having the highest priority is detected in order. When the detected base station is the second base station, a transition process for connecting to the second base station is performed only when the detected base station matches the stored base station information. And

The present invention provides a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and a first base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area. Mobile terminal equipment used in a wireless communication system comprising two base stations, a first base station in the previous period, the second base station, and a core network that manages the mobile communication terminal, When moving into the communication service area of the second base station included in the communication service area of the base station, or when moving out of the communication service area via the first base station Notification of moving from the core network into the communication service area of the second base station or moving out of the communication service area Only, and said second base station performs processing to shift to the second base station only in a communication service area are included in the communication service area of said first base station.

The present invention includes a plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area. And a second base station capable of performing communication, wherein the mobile communication terminal holds and detects base station information for identifying the second base station. In the case where the base station that has performed is the second base station, a transition process for connecting to the second base station is performed only when the base station information matches the stored base station information.

The present invention includes a plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area. A communication connection method in a wireless communication system comprising a second base station capable of performing communication, wherein the second base station is set with a connection condition that limits mobile communication terminals that can be connected, and the mobile communication The terminal holds the priority order of the second base station determined by the connection condition set in the terminal, and base station information for specifying the second base station, and the first base station or When performing detection of the second base station, detection is performed in order from the second base station with the highest priority, and when the detected base station is the second base station, the second base station retains the second base station. Base And performing a transition process that communicates with said second base station only if they match the information.

The present invention includes a plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area. A communication connection method in a wireless communication system comprising: a second base station capable of performing the above and a core network that manages the first base station, the second base station, and the mobile communication terminal in the previous period. The core network includes information on a second base station that can be connected to each mobile communication terminal, and whether the connectable second base station is included in the communication service area of the first base station. Information is held, and the mobile communication terminal moves into the communication service area of the second base station included in the communication service area of the first base station, or the communication service The mobile communication terminal has moved into the communication service area of the second base station via the first base station, or within the communication service area. The mobile communication terminal notifies the second base station only in a communication service area in which the second base station is included in the communication service area of the first base station. It is characterized by performing the transfer process.

According to the present invention, there is an effect that connection processing can be performed by appropriately selecting a base station having a different communicable range in accordance with the situation of the mobile communication terminal. As a result, broadcast information is not frequently acquired even in an environment where radio waves are always received from the base station, and location registration and cell transition processing are not performed, thereby reducing power consumption of the mobile communication terminal. Can do.

It is a figure which shows schematic structure of the mobile apparatus, macrocell base station, femtocell base station, and core network which are used in the mobile communication system of this invention. It is a figure which shows an example of the communication service area in the mobile communication system by the 1st Embodiment of this invention. It is a flowchart which shows operation | movement of the mobile communication terminal used in the 1st Embodiment of this invention. 4 is a flowchart showing a processing operation when a new base station is detected when the mobile communication terminal used in the first embodiment of the present invention is in a standby state at the macrocell base station 2; 4 is a flowchart showing an operation when the mobile communication terminal used in the first embodiment of the present invention is waiting in the femtocell base station 3; It is a figure which shows an example of the communication service area in the mobile communication system by the 2nd Embodiment of this invention. It is a flowchart which shows operation | movement when the power supply of the mobile communication terminal of the 2nd Embodiment of this invention is started. It is a flowchart which shows the processing operation when the mobile communication terminal of the 2nd Embodiment of this invention detects a new base station in standby. It is a figure which shows an example of the communication service area in the mobile communication system by the 3rd Embodiment of this invention. It is a sequence diagram which shows the processing operation between the networks containing the mobile communication terminal and base station of the 3rd Embodiment of this invention. It is a flowchart which shows the processing operation of the femtocell area determination flag of the mobile communication terminal of the 3rd Embodiment of this invention. It is a flowchart which shows the operation | movement of the base station transition of the mobile communication terminal of the 3rd Embodiment of this invention. In each embodiment of this invention, it is a figure which shows the example of a display of the screen which performs the setting of a femtocell base station from an operation menu by manual operation.

<First Embodiment>
Hereinafter, a mobile communication system according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the embodiment. In this figure, reference numeral 1 denotes a mobile communication terminal (hereinafter referred to as a mobile device) used in a mobile communication system. Reference numeral 2 denotes a macro cell base station having a wide communication service area. Reference numeral 3 denotes a femtocell base station having a specific communication service area. Reference numeral 4 denotes a core network to which the macrocell base station 2 is connected. The core network 4 is provided with an HLR (home location register) 41 and manages the position information of the mobile device 1. Reference numeral 5 denotes an IP communication network, and the femtocell base station 3 is connected to the core network 4 via the IP communication network 5. Although a plurality of macrocell base stations 2 and femtocell base stations 3 are actually installed, they are omitted in FIG.

The mobile device 1 includes an antenna unit 10 for transmitting and receiving radio signals, a radio unit 11 that converts an RF signal received by the antenna unit 10 into a baseband signal, and converts a baseband signal to be transmitted into an RF signal; The transmission unit 12 performs encoding processing and modulation processing on the transmission data to generate a baseband signal, and the reception unit 13 performs demodulation processing and decoding processing on the reception signal converted into the baseband signal by the radio unit 11. A control unit 14 that performs overall control of processing operations of the mobile device 1, an application unit 15 that performs application processing such as voice communication and packet communication service and user interface processing, and a femtocell base to which the mobile device 1 can be connected. And a femtocell information unit 16 that holds information of the station 3.

The macro cell base station 2 transmits to the mobile device 1, a CN (core network) communication unit 21 that performs communication with the core network 4, a control unit 22 that performs overall control of processing operations of the macro cell base station 2, and the mobile device 1. A transmitter 23 that generates and modulates data, a receiver 24 that receives and demodulates data transmitted from the mobile station 1, and down-converts radio signals transmitted to and received from the mobile station 1 to baseband, A radio unit 25 that up-converts signals into radio signals and an antenna unit 26 that receives or transmits radio signals are provided.

The femtocell base station 3 includes an IP communication unit 31 that communicates with the core network 4 via the IP communication network 5, a control unit 32 that performs overall control of processing operations of the femtocell base station 3, and the mobile device 1. Management of information on the mobile unit 1 that can be connected to the femtocell base station 3, and the transmission unit 33 that generates and modulates transmission data to the mobile station, the reception unit 34 that receives and demodulates the data transmitted from the mobile device 1 Terminal information unit 35, femtocell information unit 36 for managing individual information of the femtocell base station 3, transmission data is converted from a baseband signal to an RF signal, and a reception signal is converted from an RF signal to a baseband signal A radio unit 37 that receives and transmits a radio signal.

Next, operations of the mobile device 1, the macro cell base station 2, and the femto cell base station 3 will be described with reference to FIG. In the configuration shown in FIG. 1, the mobile device 1 communicates with either the macrocell base station 2 or the femtocell base station 3. When communicating with the macro cell base station 2, data to be transmitted to the mobile device 1 is transmitted to the macro cell base station 2 via the core network 4. In the macrocell base station 2, the data transmitted to the mobile device 1 is received by the CN communication unit 21. This data is sent to the transmission unit 23 via the control unit 22. The transmission unit 23 generates transmission data together with control data for controlling the mobile device 1 and sends it to the radio unit 25. The wireless unit 25 converts this transmission data into an RF signal, and transmits an RF signal from the antenna unit 26 in accordance with the correspondence of MIMO (multiple input / multiple output), transmission diversity, and the like.

The mobile device 1 receives the radio wave from the macrocell base station 2 and converts the RF signal into a baseband signal in the radio unit 11. This signal is demodulated by the receiving unit 13 and processed by the application unit 15 via the control unit 14 by an application corresponding to the received data, and processed as data for voice call, TV phone, and packet communication. The data generated by the application unit 15 is sent to the transmission unit 12 via the control unit 14. The transmission unit 12 generates a transmission signal together with the control data and sends the transmission signal to the wireless unit 11. The radio unit 11 converts the baseband signal into an RF signal and transmits it from the antenna unit 10.

The macrocell base station 2 receives the signal transmitted from the mobile device 1 by the antenna unit 26. The received signal is converted from an RF signal to a baseband signal in the radio unit 25 and demodulated by the receiving unit 24. The demodulated signal is transmitted to the core network 4 via the CN communication unit 21 and transmitted to the connection destination of the mobile device 1.

When connecting with the femtocell base station 3, the basic operation is the same as that when connecting with the macrocell base station 2, but the mobile device 1 refers to the information in the femtocell information unit 16. In the mobile device 1, the synchronization signal / broadcast information (including cell ID) transmitted from the femto base station 3 is received by the antenna unit 10 and converted into a baseband signal by the radio unit 11. This baseband signal is demodulated by the receiver 13 and passed to the controller 14. The control unit 14 confirms base station information such as a cell ID for specifying the base station stored in the femtocell information unit 16. The cell ID is an ID in which the femtocell base station 3 and the macrocell base station 2 can be distinguished. When the cell ID is the cell ID of the femtocell base station 3, the cell ID is collated with the data of the femtocell information unit 16. The femtocell information unit 16 stores information on the femtocell base station 3 to which the mobile device 1 can be connected. The cell ID of the femtocell base station 3 is also stored in this, and if the cell IDs of both do not match, it is determined that the mobile device 1 cannot be used, and the femtocell base station 3 3 is not performed.

Further, the femtocell base station 3 includes a terminal information unit 35. The femtocell base station 3 stores the information of the mobile device 1 transmitted from the mobile device 1 and the terminal information unit 35 when there is a request for location registration or base station shift (Routing Area Update) from the mobile device 1. The information of the mobile device 1 is collated using a comparison unit (not shown) of the control unit 32. This collation is confirmed by using, for example, IMSI (International Mobile Subscriber Identity). If the IMSI transmitted from the mobile device 1 matches the IMSI of the connectable terminal stored in the terminal information unit 35, the femtocell base station 3 permits the connection of the mobile device 1. If not included in the terminal information unit 35, the mobile device 1 requesting connection is determined to be a terminal that is not permitted to connect, and the control unit 32 does not permit connection of the mobile device 1.

The femtocell base station 3 is provided with a femtocell information unit 36, and an ID (identification number) unique to the femtocell base station 3 is stored therein. The ID unique to the femtocell base station 3 is registered in the core network 4 via the IP communication network 5. The core network 4 includes an HLR 41 for managing the mobile device 1. In the HLR 41, information on the mobile device 1 is managed, and information on the mobile device 1 and information on the femtocell base station 3 to which the mobile device 1 can be connected are managed together. The femtocell information unit 36 includes information on the location where the femtocell base station 3 is installed. In the HLR 41, an ID unique to the femtocell base station 3 to which the mobile device 1 can be connected and the femtocell base station. 3 manages which macro cell base station 2 is installed in the service area.

When the mobile device 1 processes a connection request (location registration or Routing Area Update, etc.) to the macrocell base station 2, the core network 4 is a femto that can be connected to the mobile device 1 in the area where the base station exists. Whether the cell base station 3 exists or not is checked against the information in the HLR 41. When it is confirmed that the core network 4 is an area where the femtocell base station 3 exists, the core network 4 notifies the mobile device 1 that the area is in that area, for example, by SMS (Short Message Service). Conversely, when the femtocell base station 3 that can be connected is present in an area where there is no femtocell base station 3 that can be connected, the mobile device 1 is notified by SMS that there is no femtocell base station 3 that can be connected.

The method of notifying whether or not the femtocell base station 3 exists is not limited to SMS, and may be notified to the mobile device 1 by packet data or control information, or the mobile device may be included in the broadcast information. A method of notifying the mobile device 1 by transmitting it together with data specifying 1 may be used. In addition, the notification can be notified only when the femtocell base station 3 moves into the area where the femtocell base station 3 exists and when the femtocell base station 3 moves out of the area, and a connection request (such as location registration or Routing Area な ど Update) A method of notifying the mobile device 1 each time may be used. Furthermore, it is also possible to provide a function of notifying whether or not the femtocell base station 3 is in the area where the mobile station 1 exists in response to a request from the mobile device 1.

Next, with reference to FIG. 2, the operation of the entire mobile communication system composed of the devices shown in FIG. 1 will be described. FIG. 2 is a diagram showing a communication service area in the mobile communication system according to the first embodiment. In FIG. 2, the communication service area indicated by reference numeral A <b> 1 is the communication service area of the macrocell base station 2. Three femtocell base stations 3-1, 3-2, and 3-3 are installed in the communication service area A1 of the macrocell base station 2, and each has a communication service area denoted by reference numerals A2, A3, and A4. is doing. Each of the femtocell base stations 3-1, 3-2, and 3-3 is used as an alternative base station when, for example, the radio wave condition of the macrocell base station 2 is poor and stable communication cannot be performed. In some cases, a user may be installed in each home in order to perform inexpensive and high-speed communication with the mobile device 1 via the IP communication network 5 (FIG. 1).

Since the mobile communication system shown in FIG. 2 uses OFDM (Orthogonal Frequency Division Multiplexing) technology, the macrocell base station 2, the femtocell base station 3-1, the femtocell base station 3-2, and the femtocell base Each of the stations 3-3 transmits data and control signals to be transmitted to the mobile device 1 by OFDM signals. The macro cell base station 2, the femto cell base station 3-1, the femto cell base station 3-2, and the femto cell base station 3-3 are each distinguished by a cell ID. The cell ID is, for example, 3GPP LTE (3rd Generation Generation Partnership Project As defined in Long コ ー ド Term 使用 Evolution (3G long-term evolution version), it is associated with the code used in the synchronization channel. In 3GPP LTE, two synchronization signals of P-SCH (Primary Synchronization Channel) and S-SCH (Secondary 準備 Synchronization Channel) are prepared. Three codes are defined for P-SCH, and this is a variable NID (2). In addition, 168 codes are defined for S-SCH, and this is variable NID (1).

The cell ID is defined as NID (CELL) = 3 × NID (1) + NID (2), and a total of 504 cell IDs can be defined. The cell ID is commonly used by the femtocell base station 3 and the macrocell base station 2. . In such a configuration, since the mobile device 1 cannot determine whether the target base station is the macro cell base station 2 or the femto cell base station 3, here, the P-SCH is expanded and the femto cell base station 3 can be distinguished. In the 3GPP LTE specifications, P-SCH takes into account the interference of each code and the like, and 25, 29, and 34 are assigned to 0, 1, and 2 of NID (2) as root indexes, respectively.

For example, the root index can be expanded as 0, 1, 2, 3 by selecting four root indexes in consideration of interference between codes in the same manner, or currently 0, 1 , 2 can be used repeatedly to determine that the value of NID (2) is 3. That is, in the macrocell base station 2, for example, the value of NID (2) is always transmitted with 1 (root index is 29), but in the femtocell base station 3, the value of NID (2) is 0 ( The root index is 25), 1 (the root index is 29), and 2 (the root index is 34). The mobile station 1 can confirm whether the value of NID (2) is 3 by receiving the P-SCH twice or more and confirming whether the value of the Root index changes. it can.

For S-SCH, a value of 168 from 0 to 167 can be used as in 3GPP LTE, and a value from 0 to 167 can be set for NID (1). For the macro cell base station 2, the value of the cell ID is NID (CELL) = 3 × NID (1) + NID (2) {NID (2) = 0, 1, 2}. In the case of the femtocell base station 3 ( In the case of NID (2) = 3), NID (CELL) = 504 + NID (1) is set.

In the example shown in FIG. 2, the macro cell base station 2 is set such that P-SCH is NID (2) = 2, S-SCH is NID (1) = 72, and the cell ID is 218. In the femtocell base station 3-1, P-SCH is set as NID (2) = 3, S-SCH is set as NID (1) = 17, and the cell ID is 521. The femtocell base station 3-3 is set as NID (2) = 3, the S-SCH is set as NID (1) = 40, and the cell ID is 544. The femtocell base station 3-2 is set as NID (2) = 3, the S-SCH is set as NID (1) = 17, and the cell ID is 521.

In such an environment, when the mobile device 1 registered in the femtocell base station 3-1 is at the position (a) shown in FIG. 2, three femtocell base stations 3-1, 3-2, 3 -3 signal cannot be received, and only the macrocell base station 2 is received. Since only the macro cell base station 2 is received, the mobile device 1 camps on the macro cell base station 2 (connection is completed) and performs communication using the macro cell base station 2.

Further, when the mobile device 1 is at the position (b) shown in FIG. 2, the mobile device 1 receives radio waves from the femtocell base station 3-1 and the macrocell base station 2. When receiving a radio wave from the femtocell base station 3-1, the mobile device 1 confirms whether or not the cell ID matches the cell ID stored in the femtocell information unit 16 inside the mobile device 1. Since the cell ID 521 of the femtocell base station 3-1 is registered in the mobile device 1, the mobile device 1 is reconnected to the femtocell base station 3-1. Normally, since the femtocell base station 3-1 and the macrocell base station 2 have different RA (Routing Area) IDs, processing of Routing Area Update (hereinafter referred to as RA update) is performed. This process can be performed in the same procedure as that used when communicating with the macrocell base station 2.

When there is a request for RA update, the femtocell base station 3-1 checks whether or not the mobile device 1 that has requested the RA update is a mobile device 1 that is permitted to communicate with its own station. That is, it is confirmed whether or not there is a mobile device 1 having the same IMSI in the terminal information registered in the terminal information unit 35 (FIG. 1). If they match, the connection is permitted and the mobile device 1 camps on the femtocell base station 3-1. Thereafter, the mobile device 1 can perform inexpensive and high-speed services with stable communication quality by performing communication through the core network 4 via the femtocell base station 3-1.

Next, when the mobile device 1 is in (d) shown in FIG. 2, it is possible to receive signals from the femtocell base station 3-2 and the macrocell base station 2. When receiving the signal from the femtocell base station 3-2, the mobile device 1 checks the value of the cell ID. In the mobile device 1, cell ID = 521 is registered as connectable femtocell information. Since the cell ID of the detected femtocell base station 3-2 is 544, the mobile device 1 determines that the detected base station is not permitted to connect, does not perform RA update processing, and performs macrocell base station 2 Keep the camp on.

By this operation, useless communication with the base station 3-2 is not performed, and useless communication load is not applied to the mobile device 1 and the femtocell base station 3-2. Moreover, the power consumption of the mobile device 1 can be reduced by not performing unnecessary transmission to the base station and eliminating unnecessary acquisition of broadcast information of other base stations.

When many femtocell base stations 3 are installed, the femtocell base station 3 has a limited ID. Therefore, even if the cell ID is the same, the femtocell base station 3 that cannot be connected may be installed. The case where the mobile device 1 is shown in (c) of FIG. 2 corresponds to this. In this case, radio waves from the femtocell base station 3-3 and the macrocell base station 2 are received. The mobile device 1 confirms the cell ID of the femtocell base station 3-3 and confirms that it matches the cell ID in the femtocell information unit 16. Therefore, the mobile device 1 performs RA update processing on the femtocell base station 3-3. The femtocell base station 3-3 confirms whether or not the mobile device 1 that requested the RA update is the mobile device 1 registered in the terminal information unit 35. In this case, since the mobile device 1 is not registered in the femtocell base station 3-3, the femtocell base station 3-3 confirms that it is an unregistered IMSI and rejects the RA update request. As a result, the mobile device 1 maintains a camp-on state at the macrocell base station 2.

Through the processing operations as described above, the mobile device 1 can connect to a desired femtocell base station 3 and waste communication resources by not performing unnecessary RA update processing. Therefore, unnecessary transmission is not performed and power consumption can be reduced. In the future, it is considered that the femtocell base station 3 will be widely used in each home. In this case, the femtocell base station 3 installed in each home is set so as not to affect the outside as much as possible. However, it is necessary to ensure stable communication in the installed home, and radio waves may leak to the outdoors. In such a situation, when the user moves outdoors with the mobile device 1, the radio wave of the femtocell base station 3 installed in each home is frequently received, but is registered in the femtocell information unit 16. If the femtocell base station 3 is not registered in the femtocell information unit 16, it is possible to obtain a great effect by not performing the RA update process. it can.

Next, the detailed operation of the mobile device 1 shown in FIG. 1 will be described with reference to FIGS. FIG. 3 is a flowchart showing an operation at the time of starting the mobile device 1 shown in FIG. First, when the mobile device 1 is powered on, the mobile device 1 performs a P-SCH search process for the femtocell base station 3 (step S1), and NID (2) = It is determined whether there is a femtocell base station 3 that is 3 (step S2). If there are a plurality of femtocell base stations 3 as a result of this determination, the mobile device 1 selects the femtocell base station 3 having the highest P-SCH reception level among them. When only one femtocell base station 3 can be detected, the femtocell base station 3 is selected (step S3). Then, the mobile device 1 acquires the S-SCH for the selected femtocell base station 3 (step S4).

Since the cell ID can be calculated when the S-SCH is acquired, it is determined whether or not the cell ID of the acquired cell matches the cell ID of the femtocell base station 3 stored in the femtocell information unit 16. Determine (step S5). If the cell IDs match, BCH (Broadcast Channel) is acquired (step S6), and location registration processing is performed (step S7). If the connection of the femtocell base station 3 is permitted, the terminal information such as the IMSI that identifies the mobile device 1 in the femtocell base station 3 matches the terminal information of the mobile device 1, so that the location registration is completed normally. Is determined (step S8). When the location registration is completed, the femtocell base station 3 enters a standby state and can perform voice or packet communication or receive an incoming voice call (step S9). If there is no information on the mobile device 1 in the terminal information held by the femtocell base station 3, the femtocell base station 3 refuses location registration, and location registration is not completed. In this case, the mobile device 1 determines whether or not there is a candidate for another femtocell base station 3 (step S10), and when the P-SCH of another femtocell base station 3 that is a candidate can be acquired. Repeats the same process.

On the other hand, when the femtocell base station 3 cannot be detected in the P-SCH search (step S1) for the femtocell base station 3, and when the femtocell base station 3 that can be connected to the detected femtocell base station 3 is If not, the mobile device 1 acquires the P-SCH for the macro cell base station 2 (step S11). Then, the mobile device 1 acquires each S-SCH (step S12), and creates a candidate list for the macrocell base station 2 (step S13). Subsequently, the mobile device 1 selects a candidate having the highest reception level from the created list of candidate macro cell base stations 2 as a base station candidate (step S14). The mobile device 1 acquires the BCH for the selected base station (step S15), performs location registration processing (step S16), and determines whether the location registration has been completed without any problem (step S17).

As a result of this determination, if the location registration process is completed without any problem, the base station enters a standby state, and thereafter communicates with the registered macrocell base station 2 (step S18). On the other hand, if the location registration process has not been performed normally, the candidate list of the macro cell base station 2 is checked to determine whether there are other candidates for connection (step S19). If there is a candidate, the same processing is performed, and the location registration processing to the macrocell base station 2 is performed (steps S14 to S16). If there is no other candidate base station, it is determined that there is no connectable macrocell base station 2 and the out-of-service state processing is performed (step S20).

Next, the processing operation when a new base station is detected in the standby state will be described with reference to FIG. FIG. 4 is a flowchart showing a processing operation when a new base station is detected when the macro cell base station 2 is in a standby state. The mobile device 1 periodically performs a neighboring cell search while waiting for the macrocell base station 2 (step S31). In this search, the mobile device 1 first searches for a P-SCH for the femtocell base station 3, that is, a search for whether there is a cell with NID (2) = 3 (step S32). If the femtocell base station 3 is present, the femtocell base station 3 is selected with the one having a high P-SCH reception level as the first candidate (step S34). Then, the mobile device 1 acquires the S-SCH for the selected femtocell base station 3 (step S35). Since the cell ID can be calculated by acquiring the S-SCH, it is determined whether or not the cell ID matches the cell ID registered in the femtocell information unit 16 (step S36).

When the cell IDs match, the mobile device 1 acquires the BCH (step S37), performs the RA update process (step S38), and determines whether the RA update process is normally completed (step S38). S39). When the RA update process is normally completed, the base station becomes an available femtocell base station 3, so that the femtocell base station 3 enters a standby state, and thereafter, via the femtocell base station 3, Communication is performed (step S40).

On the other hand, in the case of the femtocell base station 3 that is not usable, when the terminal information such as the IMSI of the mobile device 1 is confirmed in the femtocell base station 3, it becomes an unregistered mobile device 1 and registration is rejected. The RA update process does not end normally. In this case, the mobile device 1 determines whether there is another femtocell base station 3 candidate (step S41). If there is a candidate, the process returns to step S34 and the same processing is repeated.

If there is no other candidate, the mobile device 1 determines that there is no femtocell base station 3 that can be connected, and detects the macrocell base station 2. Further, even when the femtocell base station 3 does not exist in the P-SCH search for the femtocell base station 3, the macrocell base station 2 is detected. In the detection of the macro cell base station 2, the P-SCH is acquired (step S42), the S-SCH is acquired (step S43), and the candidate list of the macro cell base station 2 is updated (step S44). At that time, measurements necessary for determining whether to shift to the base station, such as reception level and path loss, are also performed. Based on the measurement result, it is determined whether or not the base station shift is necessary (step S45). If it is determined that the base station shift is not necessary, no further processing is performed, and the macrocell base station 2 that is currently camping on is determined. The standby state is maintained at (Step S46).

On the other hand, when it is determined that the base station shift is necessary, the base station to be transferred is selected (step S47). Then, the mobile device 1 acquires a BCH for the selected macrocell base station 2 (step S48), and determines whether or not there is a change in the Routing Area ID (routing area identification number, hereinafter referred to as RAID) (step S49). ). If there is no change in RAID, the macro cell base station 2 that has selected the connected macro cell base station 2 is changed (step S50), and the new macro cell base station 2 is maintained in a standby state (step S51). If the RAID is changed, the mobile device 1 performs the process of updating the RA (step S52) and maintains the standby state in the new macrocell base station 2 (step S53).

By performing the processing operations as described above, when the femtocell base station 3 is detected, it becomes possible to connect preferentially regardless of the reception level, and the femtocell base station 3 service area that can be connected When entering, it is possible to quickly connect to the femtocell base station 3. Further, when the femtocell base station 3 is not detected, and when the femtocell base station 3 is detected but is not the femtocell base station 3 to which the mobile device 1 can be connected, the search processing of the macrocell base station 2 is performed as usual. It can be carried out.

Next, with reference to FIG. 5, the operation when the femtocell base station 3 is waiting will be described. FIG. 5 is a flowchart showing an operation when the mobile device 1 is waiting at the femtocell base station 3. When the femtocell base station 3 is on standby, even if a base station is found in the neighboring cell search, only the information in the base station list is updated, and processing such as base station migration is not performed. The mobile device 1 periodically measures the reception level of the femtocell base station 3 that is currently camping on (step S61), and determines whether or not the reception level is equal to or lower than the threshold (step S62). If the reception level is higher than the threshold, even if there is a cell with a reception level higher than the current reception level, the base station is not changed and the standby state is maintained (step S63). When the reception level is equal to or lower than the threshold, the mobile device 1 confirms the candidate list of the macro cell base station 2 detected in advance (step S64), and selects, for example, a cell candidate with the maximum reception level (step S65). The RA update process is performed on the selected base station candidate (step S67), and the macro cell base station 2 performs a standby operation (step S68). By performing such processing, communication with the femtocell base station 3 can be maintained and low-cost communication can be performed while communication with the connected femtocell base station 3 is possible.

<Second Embodiment>
Next, a mobile communication system according to a second embodiment of the present invention is described with reference to the drawings. With reference to FIG. 6, operation | movement of the whole mobile communication system comprised with each apparatus shown in FIG. 1 is demonstrated. FIG. 6 is a diagram showing a mobile communication system configuration according to the second embodiment. In FIG. 6, the area indicated by reference sign A <b> 5 indicates the service area of the macrocell base station 2. In this service area A5, a femtocell base station 3-a having a service area indicated by reference symbol A6, a femtocell base station 3-b having a service area indicated by reference symbol A7, and a femto cell having a service area indicated by reference symbol A8. A cell base station 3-c and a femtocell base station 3-d having a service area indicated by reference numeral A9 are arranged. The four femtocell base stations 3-a, 3-b, 3-c, and 3-d are, for each user selection function, a femtocell base station 3-a for a specific operator and a femtocell base station 3 for all users. -B, Femtocell base stations for specific users 3-c and 3-d.

The femtocell base station 3-a for a specific operator is installed by an operator providing a wireless communication service to cover an area where the reception sensitivity of the mobile communication system is poor. -Connection is permitted only to the mobile station 1 that has contracted with the operator that has installed a and the operator that has installed this femtocell base station 3-a and has contracted with roaming. Is.

The femtocell base station 3-b for all users is a femtocell base station that does not particularly limit the type of the mobile device 1 to be connected. For example, reception sensitivity of a mobile communication system (OFDM or the like) is low in a small store or the like. It is used in cases. Since it is assumed that an unspecified number of users use the femtocell base station 3-b in the store, the service is not restricted by the mobile device 1 or the contracted business operator.

Specific user femtocell base stations 3-c and 3-d are femtocell base stations installed at home by individuals. If the reception sensitivity of the mobile communication system is not good at home, Even if there is no problem in receiving sensitivity for the purpose of improvement, it is installed for the purpose of realizing stable and high-speed wireless communication access by connecting to the base station via the IP communication network 5 Is. Since the base station is installed for an individual user, only the mobile device 1 permitted by the installed user can be connected.

The macrocell base station 2 is directly connected to the core network 4 of the mobile communication system, and the four femtocell base stations 3-a, 3-b, 3-c, and 3-d are connected to the IP communication network 5. Via the core network 4. The core network 4 includes an HLR (Home Location Register) 41 that manages the mobile device 1. When the macrocell base station 2 is a W-CDMA system or the like, it is connected to the core network 4 via an RNC (base station control device). In such an environment, when the mobile device 1 is in the location (a) shown in FIG. 6, it receives radio waves from four femtocell base stations 3-a, 3-b, 3-c, and 3-d. Therefore, the mobile device 1 is camping on the macro cell base station 2.

Next, when the mobile device 1 moves to the position (b) shown in FIG. 6, the mobile device 1 can detect the femtocell base station 3-a for the specific operator. When the specific carrier femtocell base station 3-a is detected, the mobile device 1 collates with the information of the connectable base station that the mobile device 1 has, and determines whether or not it is a connectable base station. At this time, the mobile device 1 determines whether or not the femtocell base station 3-a is a restricted base station based on the broadcast information, and if it is restricted, whether the carrier code matches. Determine whether. If they do not match, the mobile device 1 maintains a camp-on state for the macrocell base station 2. On the other hand, when the carrier codes match, the mobile device 1 moves to the femtocell base station 3-a for the specific carrier by RA update for the femtocell base station 3-a for the specific carrier.

Next, when the mobile device 1 is at the position (c) shown in FIG. 6, the femtocell base station 3-c for specific users and the macrocell base station 2 are detected. If the mobile device 1 at the position (c) shown in FIG. 6 is a mobile device that is not permitted to connect, the femtocell base station 3-c is connected to the base station of the femtocell base station 3-c. The cell ID which is the station number is determined. The mobile device 1 holds a connectable cell ID and compares it with the cell ID. In this case, since the cell IDs do not match, the mobile device 1 continues the state in which the connection to the macro cell base station 2 is maintained.

Next, when the mobile device 1 is in the position (d) shown in FIG. 6, the femtocell base station 3-d for specific users and the macrocell base station 2 are detected. Assuming that the mobile device 1 at the position (c) shown in FIG. 6 is a mobile device that is allowed to be connected, the femtocell base station 3-d includes the femtocell base station 3-d in the mobile device 1. The mobile device 1 determines whether or not the detected base station can be connected based on the cell ID. In this case, since the connection is possible, the cell ID and the cell ID inside the mobile device 1 match, so the base station migration process is performed by performing RA update.

Next, when the mobile device 1 is in the position (e) shown in FIG. 6, the femtocell base station 3-c for the specific user, the femtocell base station 3-a for the specific operator, the femtocell base for all users The station 3-b and the macrocell base station 2 are ready to receive. In this case, the mobile device 1 searches the specific user femtocell base station 3-c with priority. When the specific user femtocell base station 3-c is found, it is determined whether or not the cell ID matches the cell ID inside the mobile device 1. If they match, the base station shift processing is performed. If they do not match, the specific carrier femtocell base station 3-a is searched. As a result, if the femtocell base station 3-a for the specific carrier is found, whether or not the carrier code that can be connected to the femtocell base station 3-a is the carrier code that can be connected to the mobile device 1. Determine. In this case, since a connectable operator code is set, the base station migration process is performed by performing RA update.

Although the operation of the mobile device 1 under various environments has been briefly described above, the detailed operation of the mobile device 1 will be described below with reference to the flowchart showing the detailed operation. FIG. 7 is a flowchart showing the operation when the mobile device 1 is powered on. Here, description will be given assuming that mobile station 1 and each base station constitute an OFDM system defined in 3GPP LTE, but in 3GPP LTE, a variable for determining the ID of a base station using S-SCH. Nx (1) is 0 to 167, but here, this is expanded to set Nx (1) that can be specified by the femtocell base station 3. Since all user femtocell base stations 3-b do not require a plurality of types, Nx (1) is fixed to 170. Since the femtocell base station 3-a for the specific operator needs to identify a plurality of operators, Nx (1) is assigned between 171 and 180. Since the NID is 3 × Nx (1) + Nx (2), 30 operators can be identified by this setting. Nx (2) is a variable for determining the ID of the base station on the P-SCH. 181 to 220 are allocated to Nx (1) of the femtocell base station for the specific user. Thereby, 120 femtocell base stations 3 for specific users can be allocated. The assignment of Nx (1) is an example, and may be changed according to the number of necessary cell IDs.

When the mobile device 1 is activated in such an environment, the mobile device 1 searches the P-SCH and receives a plurality of receivable base stations (targets are both the macro cell base station 2 and the femto cell base station 3). The timing of the base station, which is not distinguished at this time, is detected (step S71). Next, S-SCH is acquired for the detected timings of the plurality of P-SCHs (step S72). The mobile device 1 creates a list of currently detected BTSs (base stations) from the acquired P-SCH and S-SCH information (step S73). This list includes information such as the cell ID calculated from P-SCH and S-SCH, the detected reception timing of the base station, and the like. Cell IDs 0 to 503 are macro cell base stations 2, 510 to 512 are femtocell base stations 3-b for all users, 513 to 542 are femtocell base stations 3-a for specific operators, and 543 to 662 are specific users. Femtocell base stations 3-c and 3-d.

The femtocell information unit 16 of the mobile device 1 has a BTS list (base station list), and individual base stations in the BTS list are assigned search priorities. In addition, the control unit 14 of the mobile device 1 includes a determination unit (not shown) that sequentially selects a type of base station having a high search priority from the BTS list. Next, the mobile device 1 determines whether or not connection is possible in order from the type of base station with the highest search priority according to the selection of the determination unit from the BTS list. The search priority is determined in advance, and from the higher priority, (1) a femtocell base station 3 for specific users, (2) a femtocell base station 3 for specific operators, and (3) femtocells for all users The order is base station 3, (4) macrocell base station 2. The mobile device 1 searches the BTS list for the specific user femtocell base station 3 having the cell IDs 543 to 662, and determines whether there are specific user femtocell base stations 3-c and 3-d. Is determined (step S74).

The mobile device 1 holds the cell ID information of the connectable specific user femtocell base station 3 registered by itself, and is a connectable cell ID depending on whether or not the cell IDs match. Whether or not (step S75). If there is information of the specific user femtocell base stations 3-c and 3-d that match the cell ID, the location registration processing is performed for the femtocell base station 3 that matches the cell ID (step S76). It is determined whether or not the position registration is completed (step S77). If the location registration is successful and completed, either one of the specific user femtocell base stations 3-c and 3-d maintains a standby state (step S78). Thereafter, services such as voice calls, videophone calls, packet communications, etc. are performed through communication with any one of the femtocell base stations for specific users 3-c and 3-d. The incoming call notification is received from the femtocell base station 3 for the specific user, and services such as voice phone, videophone, and mail are used.

Here, there is a case where the information on the femtocell base station 3 for the specific user stored in the mobile device 1 is one and there is only one femtocell base station 3 for the specific user whose cell ID matches in the BTS list. As described above, when there are a plurality of femtocell base stations 3 for specific users whose cell IDs match in the BTS list, the location registration process is sequentially performed on the base stations. The order may be arbitrarily determined. If the location registration is completed normally, the specific user femtocell base station 3 waits. If the location registration fails, the same processing is performed for the next base station. If the location registration is not normally completed for all the femtocell base stations 3 for specific users having the same cell ID, the process moves to the femtocell base station 3 for specific operators.

On the other hand, when the specific user femtocell base station 3 does not exist in the BTS list, and when the cell IDs of the connectable specific user femtocell base stations 3-c and 3-d do not exist in the BTS list, If the location registration is not completed normally (for example, when the specific user femtocell base station 3 installed by the third party happens to use the same cell ID), the location registration The process proceeds to the femtocell base station 3. The information about the femtocell base station 3-a for the specific operator is acquired from the UIM card (User Identity Module Module Card) installed in the mobile device 1. In the UIM card, an MCC / MNC of a connectable carrier or an MCC (Mobile Country Code) / MNC (Mobile Network Code) of a carrier that cannot be connected is registered. The cell ID used by such a carrier is collated with the carrier by the MNC / MCC stored in the mobile device 1 in advance from the cell ID information to obtain the cell ID.

When the mobile station 1 itself is limited to the business operators that can be connected, information on cell IDs that can be simply connected is held in the mobile unit 1 and cell IDs that can be connected are determined from the information. Also good. In addition, the MCC / MNC may be configured so that it can be updated because a new service provider may start the service or an existing provider may stop the service. The mobile device 1 determines whether or not the specific carrier femtocell base station 3-a is in the BTS list (step S79). If the specific carrier femtocell base station 3-a is in the BTS list, it is determined whether or not it matches the cell ID of the connectable carrier obtained (step S80). If they match, the location registration process is performed (step S81), and it is determined whether the location registration is completed (step S82). If completed, the standby operation is performed at the specific carrier femtocell base station 3-a (step S83). When there is no femtocell base station 3 for a specific operator, when there is no cell ID of a connectable operator, or when location registration has not been completed normally, to the femtocell base station 3 for all users Perform migration process.

The all-user femtocell base station 3-b is a base station that does not restrict users and is a base station that can always be connected. The mobile device 1 of the mobile device 1 determines whether or not there is a base station of the all-user femtocell base station 3-b (cell ID 510 to 512) in the BTS list (step S84). . If there is a corresponding base station, location registration is performed with the base station (step S85), and it is determined whether or not location registration has been completed normally (step S86). If completed successfully, the femtocell base station 3 for all users enters a standby state (step S87). Thereafter, communication is performed in the femtocell base station 3-b for all users. When the all-user femtocell base station 3 does not exist in the BTS list, and when the location registration to the all-user femtocell base station 3 is not normally completed, the location registration operation to the macrocell base station 2 Migrate to

When there is no connectable base station among the femtocell base stations 3-a, 3-b, 3-c, and 3-d, the mobile device 1 starts location registration processing with the macrocell base station 2 To do. The mobile device 1 creates a BTS list of detected base stations (step S88), and extracts a list of candidates for the macro cell base station 2 from the BTS list. From the extracted macro cell base stations 2, the base station with the maximum reception quality detected by the mobile device 1 is selected as a connection destination base station (step S89). Then, the mobile device 1 performs location registration processing for the selected macrocell base station 2 (step S90), and determines whether or not location registration has been normally completed (step S91). If the location registration process is normally completed, the mobile station is located in the registered macrocell base station 2 and performs AMR, videophone, packet communication, and the like (step S92). On the other hand, if the location registration has not been completed normally, it is determined whether there is any other detected base station (step S93). When there are a plurality of candidates, the base station with the highest reception quality is selected from the remaining candidates, and the same processing is performed. If location registration has failed for all candidates of the macrocell base station 2, the base station is periodically searched for out of service (step S94).

Next, an operation when a new base station is detected during standby will be described with reference to FIG. FIG. 8 is a flowchart showing a processing operation when a new base station is detected during standby. The mobile device 1 detects a new base station even during standby, and periodically measures whether there is a change in the reception quality of a base station that can be currently received (step S101). While waiting, detection processing of base stations located in the vicinity is performed, and when a new base station is not detected, the base station information such as the reception level of each base station is updated (step S103), and standby is performed again. The state is continued (step S104).

On the other hand, when a new base station is detected, the priority order is determined (step S105). Compare the priority of the base station that is currently waiting and the priority of the detected base station, and update the base station information if it is not a femtocell base station 3 with a high connectable priority (step S106), The standby state is maintained (step S107). If the priority is higher, the base station shift processing is performed by performing RA update (step S108), and it is determined whether or not connection is possible (step S109). If the RA processing is normally performed and connection is possible, the new base station enters a standby state, and then communication processing at the new base station is performed (step S110).

If the connection fails, the mobile device 1 determines whether there are other candidates for moving to the base station (step S111). When a plurality of base stations are detected, if there is another base station with a higher priority, the process returns to step S108 and the RA process is performed in the same manner. On the other hand, if there is no other candidate, the base station information is updated (step S112), and the standby state is maintained (step S113).

Although not shown, when the femtocell base station 3 that is connected to the macrocell base station 2 and that can be connected is not detected, whether or not the base station shift is performed according to the reception quality of the macrocell base station 2 as usual. To determine. When base station migration is necessary, the migration destination RAID is confirmed, and when the cell ID is changed, the process of updating the RA is performed. When the cell ID is not changed, the base station is changed without particularly notifying the base station.

By performing the above processing, it is not necessary to frequently perform location registration or base station migration processing for a base station (femtocell base station 3) that is not permitted to be connected. Can be reduced. Further, by registering the femtocell base station 3 capable of performing high-speed communication and the femtocell base station 3 for which a connection fee is preferentially registered as a base station having a high priority, a base station (femtocell base station) having user merit is registered. When the station 3) has been supplemented, connection to the base station can be realized quickly without depending on the reception level.

The above description has been made on the assumption that the selection priority order of the femtocell base station 3 and the macrocell base station 2 is automatically set, but the selection method is not only set automatically by the mobile device 1 but also manually by the user. It is also possible to set by operation. When performing selection by manual operation, the user calls the setting screen of the femtocell base station 3 from the operation menu of the mobile device 1.

The priority selection screen has a determination key at the upper right of the pop-up screen, and a selection screen for each type of femtocell base station 3 at the lower side. On such a screen, it is possible to switch the item on the list by pressing the enter key at a place where the user is focused on the type of the femtocell base station 3. For example, in the display example shown in FIG. 13, when “3. Femtocell base station for all users” is selected and the determination key is pressed, “3. Femtocell base station for all users” can be replaced. . If you press the up arrow key, the focused line will be replaced with the item above, the second will be "All users femtocell base station" and the third will be "specific operator femtocell base station" " When it is determined again, this order is provisionally determined, and no femtocell base station type is focused. In this state, the order is fixed by pressing the enter key. The above selection method is an example showing that the user can select the function of the present invention by manual operation, and does not limit the selection method, display method, and setting method, and does not limit the first to fourth items. A list of options that can be set may be displayed and set freely. In this case, since settings may be duplicated, if settings are duplicated, it is necessary to display a warning screen and prompt the user to make corrections.

<Third Embodiment>
Next, a mobile communication system according to a third embodiment of the present invention is described with reference to the drawings. With reference to FIG. 9, the operation of the mobile communication system configured with each device shown in FIG. 1 will be described. FIG. 9 is a diagram showing a communication service area in the mobile communication system according to the third embodiment. In FIG. 9, symbols RA1 and RA2 indicate two routing areas having different RAID (routing area identification). In the routing area RA1, there are a plurality of macro cell base stations 2. In FIG. 9, the communication service areas RA1-11, RA1-12, RA1-13 include three macrocell base stations 2-11, 2-12, 2-13 shows a communication service area.

Similarly for the routing area RA2, the communication service areas RA2-21, RA2-22, and RA2-23 indicate the communication service areas of the three macro cell base stations 2-21, 2-22, and 2-23. A femtocell base station 3 is installed in the communication service area RA2-21. 9 indicates that the mobile device 1 moves in the order of (A) to (B), (C), (D), (E), and (F). This mobile device 1 is a mobile device 1 that is permitted to communicate with the femtocell base station 3 in the communication service area RA2-21. Although not shown, the femtocell base station 3 includes a plurality of femtocell base stations 3 in both the routing areas RA1 and RA2. However, the femtocell base station 3 is controlled to refuse connection except for the registered mobile devices 1, and the mobile device 1 in the figure can connect to these femtocell base stations 3. Can not.

Further, as shown in FIG. 1, the mobile device 1 includes a femtocell information unit 16 that holds information about connectable femtocell base stations 3, and the femtocell base station 3 communicates with the femtocell information unit 16. A storage unit (not shown) for storing a femtocell area determination flag for determining a service area is included. The initial value of the femto cell area determination flag is 0, indicating that the femto cell base station 3 is located in an area where there is no connectable femto cell base station 3. In this example, the cell ID of the base station is not expanded, and both the femtocell base station 3 and the macrocell base station 2 use cell IDs from 0 to 503.

First, when the mobile device 1 is located in the communication service area RA1-12, the femtocell area determination flag is 0. When the femtocell area determination flag is 0, there is no femtocell base station 3 that can be connected, so the mobile device 1 performs the operation defined in 3GPP, and the macrocell base station 2 in the communication service area RA1-12 Perform necessary communication. When the mobile device 1 moves from the position (A) to the position (B) shown in FIG. 9, the communication service area in the area is changed from RA1-12 to RA1-13. In this case, since the RAID remains unchanged in the routing area RA1, the mobile device 1 simply changes the standby base station from the macro cell base station 2-12 to the macro cell base station 2-13.

Next, when the mobile device 1 moves from the position (B) to the position (C) shown in FIG. 9, the receivable base station changes from the macro cell base station 2-13 to the macro cell base station 2-22. When moving to the macro cell base station 2-22, the mobile device 1 executes the process of updating the RA because the RAID before and after the movement is different. By this RA update process, the mobile device 1 is located in the communication service area RA2-22. When the mobile device 1 performs RA update, the core network 4 refers to the terminal information stored in the HLR 41. The HLR 41 manages in advance where the position of the femtocell base station 3 to which the mobile device 1 can be connected is. If connection to a plurality of femtocell base stations 3 is possible, information on all the femtocell base stations 3 is managed. Further, the position information is stored in association with the information of the macro cell base station 2 so that it can be understood in which communication service area of the macro cell base station 2 exists.

Since the macro cell base station 2 in the communication service area where the femtocell base station 3 exists can be specified, the RAID where the macro cell base station 2 exists can also be specified. When the mobile device 1 performs the RAID update and the RAID in the area is changed, the base station determines whether or not the RAID matches the RAID in which the femtocell base station 3 to which the mobile device 1 can be connected exists. If they do not match, nothing is done. If they match, it is notified that the femtocell base station 3 that can be connected to the mobile device 1 has moved to the communication service area. The communication service area RA2-22 exists in the routing area RA2. Since the routing area RA2 includes the communication service area RA2-21 in which the femtocell base station 3 to which the mobile device 1 can be connected is present, an area where the femtocell base station 3 may be detected by the mobile device 1 It is notified by SMS that it moved to.

The method of notifying the mobile device 1 may use, for example, packet arrival or control information other than SMS. The mobile device 1 that has received the SMS changes the femtocell area determination flag from 0 to 1, and thereafter searches the femtocell base station 3 preferentially. The mobile device 1 holds the cell ID information of the femtocell base station 3 to which the mobile device 1 can be connected, and when there is a base station having the same cell ID information among the detected base stations, the base station Perform processing to move to the base station. When the mobile device 1 is at the position (C) shown in FIG. 9, the macro cell base station 2-22 is detected, and the cell ID of the macro cell base station 2-22 is connected to the mobile device 1 Does not match the cell ID of a possible femtocell base station. For this reason, necessary communication is performed by normal processing.

Next, when the mobile device 1 moves to the position (D) shown in FIG. 9, the mobile device 1 receives radio waves from both the femtocell base station 3 and the macrocell base station 2-21. Since the cell ID of the femtocell base station 3 matches the cell ID of the connectable femtocell base station 3 held by the mobile device 1, the reception quality of the macrocell base station 2-21 is better than the femtocell base station. Even if it is better than the reception quality of 3, the base station shift processing is performed on the femtocell base station 3. At this time, depending on the reception status of the femtocell base station 3 and the processing of the mobile device 1, there is a case where the mobile station 1 immediately shifts to the femtocell base station 3, and once the cell shifts to the macrocell base station 2-21, May move. When moving to the macro cell base station 2-21, the macro cell base station 2-21 is included in the routing area RA2, and the mobile device 1 is already in the area including the femtocell base station 3. Therefore, the mobile device 1 is not particularly notified. When performing base station migration, first, broadcast information of the destination base station is acquired, but RAID is included in the broadcast information. Since the femtocell base station 3 has a RAID different from that of the macrocell base station 2-21 or the macrocell base station 2-22, the femtocell base station 3 shifts to the base station by RA update. The femtocell base station 3 does not perform notification for updating the femtocell area determination flag. For this reason, the mobile device 1 maintains the femtocell area determination flag in the 1 state.

Next, when the mobile device 1 moves to the position (E) shown in FIG. 9, since the femtocell base station 3 cannot receive, the base station shifts to the macrocell base station 2-21. Also in this case, since the RAID included in the macro cell base station 2-21 is different, the base station is shifted by the process of updating the RA. The macro cell base station 2-21 is determined to be an area including the femtocell base station 3 because the RAID is the routing area RA2, and notifies the mobile device 1 to update the femtocell area determination flag. The mobile device 1 receives the notification indicating that it has entered the communication service area of the femtocell base station 3, but since the femtocell area determination flag has already been 1, the state is maintained.

Next, when the mobile device 1 moves to (F) shown in FIG. 9, the RAID changes from RA2 to RA1. Therefore, the mobile device 1 performs RA update processing. In the core network 4, this process is used as a trigger to determine whether this routing area includes the femtocell base station 3 to which the mobile device 1 can be connected. Since the connectable femtocell base station 3 is not included, the mobile station 1 is notified of the information. The mobile device 1 changes the femtocell area determination flag from 1 to 0 when notified from the base station that it has moved to a communication service area that does not include the femtocell base station 3. Thereafter, the process of preferentially connecting the femtocell base station 3 is stopped, and the process of cell selection and base station shift is performed as usual.

Next, the detailed operation of the mobile device 1 in the third embodiment will be described with reference to FIGS. FIG. 10 is a sequence diagram showing processing operations between the network including the mobile device 1 and the base station. As described above, the femtocell area determination flag is 0 in the initial state, and the femtocell base station 3 that can be connected is in a communication service area. Therefore, the mobile device 1 periodically performs a cell search as usual (step S121), and determines whether or not to change the connected base station based on the reception level, reception quality, etc. of the neighboring cells. As a result, when the reception quality of the base station currently in the service area deteriorates and it is determined that the base station should move to another base station, the broadcast information of the destination base station is acquired. The broadcast information includes information (ID) for determining the routing area, and when this value is the same, the mobile device 1 changes the base station in the area as it is. If the RAIDs are different, it is determined that routing area update processing is necessary (RA update factor is generated) (step S122).

The mobile device 1 performs processing for updating the routing area with respect to the base station (step S123). When the routing area update process is completed, the network side checks whether or not the femtocell base station 3 to which the mobile device 1 can be connected is registered in the routing area to which the mobile device 1 is newly connected (step). S124). This information is stored as information in the HLR 41 of the core network 4 (FIG. 1), for example. Alternatively, the femtocell base station 3 may have a dedicated storage area for management for storing this information. When the network side confirms that it is within the communication service area of the femtocell base station 3, the fact that the femtocell base station 3 has moved to a certain communication service area is notified by SMS (step S125). When the mobile device 1 receives the SMS notifying that the femtocell base station 3 exists, the mobile device 1 updates the information in the mobile device 1 and confirms the reception to the network side by SMS (step S126). . By doing so, when there is no response of the reception confirmation from the mobile device 1 side, the network side notifies again that there is the femtocell base station 3, and is located in the communication service area of the femtocell base station 3. Information on whether or not there is can be appropriately updated.

Next, the mobile device 1 performs processing for preferentially searching for the femtocell base station 3 (step S127). Even when the mobile station 1 is out of the communication service area where the femtocell base station 3 to which the mobile station 1 can be connected is present, the RAID is acquired from the broadcast information of the destination base station, the RA update factor is generated, and the RA update is required. Is confirmed (step S128). Then, RA update processing is performed on the network side (step S129). On the network side, it is confirmed whether or not there is an area in which the femtocell base station 3 to which the mobile device 1 can be connected exists (step S130), and femtocells that can be connected from the area in which the femtocell base station 3 to which connection is possible exist. When the base station 3 moves to an area where it does not exist, a notification indicating this is transmitted by SMS (step S131). When receiving this information, the mobile device 1 updates the information in the mobile device 1 and notifies the network side of reception confirmation by SMS (step S132). Thereafter, the process of preferentially connecting the femtocell base station 3 is terminated, and the normal cell selection / base station transition process is continued (step S133).

Next, the processing operation of the femtocell area determination flag of the mobile device 1 will be described with reference to FIG. FIG. 11 is a flowchart showing the processing operation of the femtocell area determination flag of the mobile device 1. The mobile device 1 performs a position registration process after the power is turned on (step S140). When the location registration process is performed, the mobile device 1 sets a femtocell area determination flag to 0 as an initial state. When the location registration process is performed, the network side notifies the mobile device 1 whether or not the mobile station 1 is in the area of the femtocell base station 3 (step S141). Then, the mobile device 1 updates the femtocell area determination flag based on the notified setting (step S142). By performing such processing, even when power is turned on in an area where the femtocell base station 3 exists, it is possible to shift to a state in which the femtocell base station 3 is preferentially connected.

Next, the mobile device 1 transitions to a standby state, and when communication is required, it performs this base station (step S143). In addition, the mobile device 1 periodically performs detection of neighboring cells, level measurement, and the like (step S144), and confirms whether or not the base station shift is necessary by this detection processing. The broadcast information of the base station to be acquired is acquired, and it is determined whether or not RA update is necessary (step S145). If it is not necessary, the femtocell area determination flag is not updated, so if there is a necessary process in the mobile device 1, the process is performed, and the process ends without updating the femtocell area determination flag and returns to the standby state. If RA update processing is required, RA update processing is performed (step S146).

When the RA update process is completed, it is determined whether or not the SMS of the femto cell area determination notification has been received (step S147). If no SMS is received for a certain period of time, a timeout occurs and the update of the femto cell area determination flag is performed. As unnecessary, it transits to a normal standby state (step S148). When the SMS is received, it is determined whether or not the received SMS is related to femtocell area determination that can be connected (step S149). If it is a normal SMS mail, the mail is processed as usual (step S150), and it returns to the standby state. If it is SMS related to the femto cell area determination, the femto cell area determination flag is updated (step S151), and the process returns to the standby state.

Next, with reference to FIG. 12, the operation of the mobile device 1 for shifting to the base station will be described. FIG. 12 is a flowchart showing the operation of the mobile device 1 for shifting to the base station. The mobile device 1 performs a neighbor cell search (step S161) while waiting (step S160). As a result of the neighbor cell search, it is determined whether or not the user is in the femtocell base station 3 (step S162). If the user is in the femtocell base station 3, only the result of the neighbor cell search is obtained. Is updated to return to the standby state (step S163).

On the other hand, if the mobile station 1 is not within the femtocell base station 3, the mobile device 1 checks the state of the femtocell area determination flag (step S164). If the femtocell area determination flag is 1, the mobile station 1 It is determined whether or not there is a base station that matches the cell ID of the base station held in the information unit 16 (step S165). If there is a matching base station, RA update processing is performed (step S166), and the femtocell base station 3 enters a standby state (step S167).

Next, when the femtocell area determination flag is 0, and when the femtocell base station 3 determination flag is 1, but there is no base station having an ID that matches the ID of the base station held in the femtocell information unit 16 The mobile device 1 determines whether or not a normal base station shift is necessary (step S168). If the base station shift is not necessary, the mobile device 1 shifts to a standby state as it is (step S169). If the reception quality of the currently received base station and neighboring base stations is received and the base station shift is necessary, the base station shift processing is performed (step S170), and the standby state is returned (step S171).

By performing the above processing, when there is a femtocell base station 3 to which the mobile device 1 can be connected, the femtocell base station 3 can be preferentially connected. Further, in an area where the femtocell base station 3 to which the mobile device 1 can be connected does not exist, even if the base station ID matches the femtocell base station 3 to which the mobile device 1 can be connected, the base station shift processing is performed as usual. In other words, even if base stations with the same cell ID are detected, the base station migration process can be performed as usual. In the third embodiment, the case where the cell ID of the base station is not expanded has been described. However, the femtocell base station to which the mobile device 1 can be connected by combining with the first embodiment or the second embodiment. In the area where 3 is present, it is possible to obtain the same effect as the first embodiment or the second embodiment. In the first embodiment, the second embodiment, and the third embodiment, the processing method is shown in a system using LTE OFDM as a communication method. However, the communication method is limited to the LTE OFDM method. Instead, other communication methods such as LTE-Advanced and Code-Division-Multiple-Access (CDMA), which are considered as the next system of LTE in 3GPP, may be used.

A program for realizing the functions of the mobile device 1, the macro cell base station 2 and the femtocell base station 3 shown in FIG. 1 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is recorded on the computer. The mobile station connection process in the mobile communication system may be performed by reading the system and executing it. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM or a CD-ROM, and a hard disk incorporated in a computer system. Further, the “computer-readable recording medium” refers to a volatile memory (RAM) in a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In addition, those holding programs for a certain period of time are also included.

The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, what is called a difference file (difference program) may be sufficient.

Depending on the situation of the mobile communication terminal, a base station with a different communicable range is appropriately selected to perform connection processing, but this can be applied to essential applications.

DESCRIPTION OF SYMBOLS 1 ... Mobile device, 10 ... Antenna part, 11 ... Radio | wireless part, 12 ... Transmission part, 13 ... Reception part, 14 ... Control part, 15 ... Application part, 16 ... Femtocell information part, 2 ... Macrocell base station, 21 ... CN communication part, 22 ... Control part, 23 ... Transmitting part, 24 ... Receiving part, 25 ... Wireless Unit, 26 ... antenna unit, 3 ... femtocell base station, 31 ... IP communication unit, 32 ... control unit, 33 ... transmission unit, 34 ... reception unit, 35 ... Terminal information part 36 ... Femtocell information part 37 ... Radio part 38 ... Antenna part 4 ... Core network 41 ... HLR 5 ... IP communication network

Claims (11)

A plurality of mobile communication terminals;
A first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area;
A wireless communication system comprising: a second base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area,
The mobile communication terminal is
An information unit for distinguishing the second base station from the first base station and storing base station information for further specifying the second base station;
A control unit that compares the base station information transmitted from the first or second base station with the base station information stored in the information unit, and if the result of the comparison matches, the process of base station transition A wireless communication system. The wireless communication system according to claim 1, wherein the mobile communication terminal performs a transition process to the second base station without depending on communication quality with the individual base station. A plurality of mobile communication terminals;
A first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area;
A wireless communication system comprising: a second base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area,
The mobile communication terminal is
Base station information for distinguishing the second base station from the first base station and further specifying the second base station, to which a base station search priority is assigned An information section for storing station information;
A wireless communication system, comprising: a determination unit that determines whether or not connection is possible in order from the type of base station having the highest base station search priority. The mobile communication terminal performs a transition process to the second base station with the highest priority among the detected second base stations without depending on the communication quality with the second base station. The wireless communication system according to claim 3. A plurality of mobile communication terminals;
A first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area;
A second base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area;
A wireless communication system comprising a core network for managing the first base station, the second base station, and the mobile communication terminal in the previous period,
The core network includes information on a second base station that can be connected to each mobile communication terminal, and information on whether the connectable second base station is included in the communication service area of the first base station. And the mobile communication terminal moves into the communication service area of the second base station included in the communication service area of the first base station, or moves out of the communication service area. The mobile communication terminal has moved into the communication service area of the second base station or moved out of the communication service area via the first base station. Notify
The mobile communication terminal performs a transition process to the second base station only in a communication service area in which the second base station is included in the communication service area of the first base station. Wireless communication system. A first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and a second base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area A mobile communication terminal device used in a wireless communication system comprising:
When the base station information for specifying the second base station is held and the detected base station is the second base station, only when the base station information matches the held base station information A mobile communication terminal that performs a transition process for connecting to the second base station. A first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and a second base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area A mobile communication terminal device used in a wireless communication system comprising:
The second base station, which can be connected, retains the priority order of the second base station determined by limited connection conditions, and base station information for specifying the second base station, and the first base station When detecting the station or the second base station, the detection is performed in order from the second base station having the higher priority, and when the detected base station is the second base station, A mobile communication terminal apparatus that performs a transition process for connecting to the second base station only when it matches the stored base station information. A first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and a second base station capable of performing wireless communication with the mobile communication terminal in a specific communication service area And a mobile communication terminal device used in a wireless communication system comprising a core network that manages the first base station, the second base station, and the mobile communication terminal in the previous period,
When moving into the communication service area of the second base station included in the communication service area of the first base station, or when moving out of the communication service area, the first base station The second base station receives a notification from the core network that the mobile station has moved into the communication service area of the second base station or moved out of the communication service area. A mobile communication terminal apparatus that performs a transition process to the second base station only in a communication service area included in a communication service area of one base station. A plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area A communication connection method in a wireless communication system comprising a possible second base station,
The mobile communication terminal holds base station information for specifying the second base station, and when the detected base station is the second base station, the held base station information The communication connection method is characterized in that a transition process for connecting to the second base station is performed only when they match. A plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area A communication connection method in a wireless communication system comprising a possible second base station,
The second base station is set with a connection condition that limits the mobile communication terminals that can be connected,
The mobile communication terminal holds the priority order of the second base station determined by the connection condition set in the mobile communication terminal and base station information for specifying the second base station, and When detecting the base station or the second base station, the detection is performed in order from the second base station with the highest priority, and when the detected base station is the second base station. A communication connection method, wherein a transition process for connecting to the second base station is performed only when the stored base station information matches. A plurality of mobile communication terminals, a first base station capable of performing wireless communication with the mobile communication terminal in a wide communication service area, and wireless communication with the mobile communication terminal in a specific communication service area A communication connection method in a wireless communication system comprising a possible second base station and a core network that manages the first base station, the second base station, and the mobile communication terminal in the previous period,
The core network includes information on a second base station that can be connected to each mobile communication terminal, and information on whether the connectable second base station is included in the communication service area of the first base station. And the mobile communication terminal moves into the communication service area of the second base station included in the communication service area of the first base station, or moves out of the communication service area. The mobile communication terminal has moved into the communication service area of the second base station or moved out of the communication service area via the first base station. Notify
The mobile communication terminal performs a transition process to the second base station only in a communication service area in which the second base station is included in the communication service area of the first base station. Communication connection method.

Images