Abstract:
Provided is compact base station device that reduces the processing load with an upper layer network device by reducing the amount of signaling with an upper layer network device. In the device, a CSG member management device ( 102 ) stores CSG member information beforehand. A network message generation unit ( 107 ) generates a message used for collectively registering the CSG member terminals stored in the CSG member management unit ( 102 ), in an upper layer network device. At startup, a network interface unit ( 108 ) transmits a message generated by the network message generation unit ( 107 ) to the upper layer network device. In response to the message transmitted by the network interface unit ( 108 ), a network message analysis unit ( 106 ) acquires from the upper layer network device parameter information for connecting to the CSG member terminals.

Description:
TECHNICAL FIELD 
     The claimed invention relates to a small cell and a signaling method. The claimed invention relates to a small cell and a signaling method where connections are established and released for terminals within a limited area, such as a home or an office, for example. 
     BACKGROUND ART 
     In recent years, consideration has been given to installing small cells (Home NodeBs: HeNBs) within limited areas, such as homes or offices, and carrying out high-speed communications with only limited users, such as closed subscriber group (CSG) members, using those small cells. Standardization efforts regarding such small cells arc being made by the 3GPP. The term CSG members, in this context, refers to grouped users managed by a small cell. 
     It is speculated that small cells are generally used for data communications and connected to household devices, such as personal computers, television sets, and/or the like. By being connected to a variety of such household devices, the number of connected terminals increases for small cells. This leads to the problem of increased signaling traffic for the core network to process. 
     It is known that a small cell gateway (HeNB GW) is sometimes disposed as an intermediate node between a small cell and an Evolved Packet Core (EPC) (e.g., NPL 1). According to NPL 1, in MME, by having a small cell gateway appear as a small cell, it is possible to keep interfaces from increasing. 
     CITATION LIST 
     Non-Patent Literature 
     NPL 1: 3GPP TS36.300 
     SUMMARY OF INVENTION 
     Technical Problem 
     However, in NPL 1, while it may be possible to keep interfaces from increasing, signaling traffic cannot be reduced since each terminal would he signaling individually. Therefore, NPL 1 has a problem in that the processing load on an upper layer network apparatus cannot be reduced. 
     An object of the claimed invention is to provide a small cell and a signaling method that are capable of mitigating the processing load on an upper layer network apparatus by reducing signaling traffic to/from the upper layer network apparatus. 
     Solution to Problem 
     A small cell of the claimed invention includes: a management means configured to pre-store information regarding grouped terminals; a generation means configured to generate a message for collectively registering the grouped terminals with an upper layer network apparatus; a network transmission means configured to transmit the message generated by the generation means to the upper layer network apparatus at a predetermined time; and an acquisition means configured to acquire from the upper layer network apparatus, as a response to the message transmitted by the network transmission means, a parameter for connecting with the grouped terminals. 
     A signaling method of the claimed invention is a signaling method for a small cell, including: a step of pre-storing information regarding grouped terminals; a step of generating a message for collectively registering the grouped terminals with an upper layer network apparatus; and a step of transmitting the generated message to the upper layer network apparatus at a predetermined time. 
     Advantageous Effects of Invention 
     According to the claimed invention, the processing load on an upper layer network apparatus may be mitigated by reducing signaling traffic to/from the upper layer network apparatus. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram showing the configuration of a small cell according to an embodiment of the claimed invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     An embodiment of the claimed invention is described in detail below with reference to the drawing. 
     (Embodiment) 
       FIG. 1  is a block diagram showing a configuration of small cell  100  according to an embodiment of the claimed invention. 
     Small bell  100  generally includes CSG member parameter management section  101 , CSG member management section  102 , CSG member connection state management section  103 , HeNB control section  104 , terminal proxy function section  105 , network message analysis section  106 , network message generation section  107 , network interface section  108 , radio message generation section  109 , radio message analysis section  110 , radio interface section  111 , and antenna  112 . 
     CSG member parameter management section  101  manages information that is necessary for radio access of CSG member terminals. Specifically, CSG member parameter management section  101  stores parameter information for CSG member terminals as notified by terminal proxy function section  105 . Upon request by HeNB control section  104 , CSG Member parameter management section  101  outputs stored CSG member parameter information to HeNB control section  104 . 
     CSG member management section  102  stores CSG member information, which is information regarding CSG member terminals capable of connecting with small cell  100 . 
     CSG member connection state management section  103  stores connection states of CSG member terminals with respect to all cell  100  as notified by HeNB control section  104 . By way of example, CSG member connection state management section  103  stores connection states indicating registration or release. 
     Based on messages received from terminals, as well as on various information stored on CSG member parameter management section  101 , CSG member management section  102 , and CSG member connection state management section  103 , HeNB control section  104  controls small cell  100 . Specifically, HeNB control section  104  controls small cell  100  when small cell  100  is activated, when connection is established with a CSG member terminal, when connection with a CSG member terminal is released, when connection is established with a non-CSG member terminal, when connection with a non-CSG member terminal is released, or when a change is made to the CSG member terminals stored on CSG member management section  102 . In so doing, HeNB control section  104  requests radio message generation section  109  or network message generation section  107  to generate a message. HeNB control section  104  acquires, from radio message analysis section  110  or network message analysis section  106 , analysis information, which is an analysis result for a message received from a terminal or an upper layer network apparatus. Specific control methods at HeNB control section  104  will hereinafter be described. 
     Terminal proxy function section  105  operates as a proxy for a CSG member terminal to the upper layer network apparatus. Specifically, in accordance with an instruction by HeNB control section  104 , terminal proxy function section  105  requests message creation, while also notifying CSG member parameter management section  101  of parameter information that is necessary in order for a terminal to connect with small cell  100 . 
     Network message analysis section  106  analyzes messages received from the upper layer network apparatus via network interface section  108 , and outputs analysis information to terminal proxy function section  105  or HeNB control section  104 . 
     Based on information and requests received from HeNB control section  104  or terminal proxy function section  105 , network message generation section  107  generates messages to be transmitted to the upper layer network apparatus. Network message generation section  107  transmits the generated messages to the upper layer network apparatus via network interface section  108 . 
     Network interface section  108  function as an interface for the upper layer network apparatus. 
     Based on information and requests received from HeNB control section  104 , radio message generation section  109  generates messages to be transmitted to terminals. Radio message generation section  109  transmits the generated messages to terminals via radio interface section  111  and antenna  112 . 
     Radio message analysis section  110  analyzes messages received from terminals via antenna  112  and radio interface section  111 . Radio message analysis section  110  outputs analysis information to HeNB control section  104 . 
     Radio interface section  111  functions as an interface for terminals. 
     Antenna  112  transmits and receives messages, and/or the like, to and from terminals. 
     Operations of small cell  100  are described below. 
     Operations of small cell  100  are described below in the following order: (1) CSG member terminal registration operation; (2) activation operation; (3) operation to connect with CSG member terminal; (4) operation to release connection with CSG member terminal; (5) operation to connect with non-CSG member terminal; (6) operation to release connection with non-CSG member terminal; and (7) operation for when a change is made to CSG member terminals. 
     (1) CSG Member Terminal Registration Process 
     CSG member terminals are registered with small cell  100  by a user managing small cell  100 . Specifically, CSG member management section  102  stores CSG member information regarding the CSG member terminals. 
     (2) Activation Process 
     HeNB control section  104  establishes connection with the upper layer network apparatus through a procedure similar to known procedures. 
     Once the above-mentioned connection is established, HeNB control section  104  acquires from CSG member management section  102  the CSG member information stored on CSG member management section  102  through operation (1) mentioned above. 
     HeNB control section  104  references the acquired CSG member information and instructs terminal proxy function section  105  to collectively register CSG member terminals with the upper layer network apparatus. 
     Upon receiving the above-mentioned information collective registration instruction, terminal proxy function section  105  requests network message generation section  107  to generate a collective registration message for collectively registering CSG member terminals. 
     Network message generation section  107  generates a collective registration message in accordance with the above above-mentioned request. 
     The generated collective registration message is transmitted to the upper layer network apparatus via network interface section  108 . 
     Upon receiving the collective registration message and completing collective registration of the CSG member terminals, the upper layer network apparatus transmits to small cell  100  a connection message including a parameter that is necessary in order for the registered CSG member terminals to connect with small cell  100 . 
     Small cell  100  receives the above-mentioned connection message via network interface section  108 . 
     Network message analysis section  106  analyzes the received connection message, and notifies terminal proxy function section  105  of analysis information regarding the result of the analysis. 
     Based on the above-mentioned analysis information, terminal proxy function section  105  notifies CSG member parameter management section  101  of parameter information that is necessary in order for CSG member terminal to connect with small cell  100 . 
     CSG member parameter management section acquires the parameter information from terminal proxy function section  105 , and manages parameter information that is necessary in order for CSG member terminals to connect with small cell  100 . 
     (3) Operation to Connect with CSG Member Terminal 
     Radio interface section  111  receives a connection request message from a CSG member terminal via antenna  112 . 
     Radio message analysis section  110  analyzes the connection request message received by radio interface section  111 , and notifies HeNB control section  104  of analysis information regarding the result of the analysis. 
     Using the above-mentioned analysis information HeNB control section  104  references the CSG member information stored on CSG member management section  102 , thereby determining whether or not the terminal that transmitted the connection request message is stored on CSG member management section  102  as a CSG member. 
     If it is determined that the terminal is stored as a CSG member terminal, HeNB control section  104  requests CSG member parameter management section  101  to output (issue) the parameter information of the corresponding CSG member. 
     In accordance with the output request from HeNB control section  104 , CSG member parameter management section  101  outputs the required parameter information to HeNB control section  104 . 
     HeNB control Section  104  sends radio message generation section  109  a message generation request for message including the parameter information outputted from CSG member parameter management section  101 . 
     HeNB control section  104  stores on CSG member connection state management section  103  the connection state of the corresponding CSG member. 
     Radio message generation section  109  generates a connection response message based on the message generation request from HeNB control section  104 . 
     Via radio interface section  111  and antenna  112 , the generated connection response message is transmitted to the terminal that transmitted the connection request message. 
     (4) Operation to Release Connection with CSG Member Terminal 
     Radio interface section  111  receives a release request message from a CSG member terminal via antenna  112 . 
     Radio message analysis section  110  analyzes the release request message received at radio interface section  111 , and notifies HeNB control section  104  of analysis information regarding the result of the analysis. 
     Using the above-mentioned analysis information, HeNB control section  104  references the CSG member information stored on CSG member management section  102 , thereby determining whether or not the terminal that transmitted the release request message is stored on CSG member management section  102  as a CSG member. 
     If it is determined that the terminal is stored as a CSG member terminal, HeNB control section  104  references the connection states stored on CSG member connection state management section  103  and determines whether or not connection is to be released. 
     If it is determined that connection is to be released, HeNB control section  104  sends radio message generation section  109  a generation request for a release response message of a release response. 
     HeNB control section  104  also updates the corresponding CSG member terminal&#39;s connection state stored on CSG member connection state management section  103  to a connection state indicating that connection has been released. 
     Upon receiving the above-mentioned generation request for a release response message, radio message generation section  109  generates a release response message. 
     Via radio interface section  111  and antenna  112 , the generated release response message is transmitted to the terminal that transmitted the release request message. 
     (5) Operation to Connect with Non-CSG Member Terminal 
     Radio interface section  111  receives a connection request message from a non-CSG member terminal via antenna  112 . 
     Radio message analysis section  110  analyzes the connection request message received at radio interface section  111 , and notifies HeNB control section  104  of analysis information regarding the result of the analysis. 
     Using the received analysis information, HeNB control section  104  references the CSG member information stored on CSG member management section  102 , thereby determining whether or not the terminal that transmitted the connection request message is stored on CSG member management section  102  as a CSG member. 
     If it is determined that the terminal is not stored as a CSG member, HeNB Control section  104  determines that the terminal is a non-CSG member terminal. Using any known and ordinary connection procedure and via network message generation section  107  and network interface section  108 , HeNB control section  104  then registers with the upper layer network apparatus the non-CSG member terminal that transmitted the connection request message. 
     The upper layer network apparatus transmits a registration notification message indicating the above-mentioned registration. 
     Network message analysis section  106  acquires the registration notification message via network interface section  108 , and analyzes the acquired registration notification message. 
     Upon acquiring analysis information regarding the above-mentioned analysis from network message analysis section  106 , HeNB control section  104  determines that registration with the upper layer network apparatus has been completed, and sends radio message generation section  109  a message generation request for a release response message with respect to the non-CSG member terminal. 
     In accordance with the message generation request from HeNB control section  104 , radio message generation section  109  generates a release response message. 
     Via radio interface section  111  and antenna  112 , the generated release response message is transmitted to the non-CSG member terminal that transmitted the connection request message. 
     (6) Operation to Release Connection with Non-CSG Member Terminal 
     Radio interface section  111  receives a release request message from a non-CSG member terminal via antenna  112 . 
     Radio message analysis section  110  analyzes the release request message received at radio interface section  111 , and notifies HeNB control section  104  of analysis information regarding the result of the analysis. 
     Using the analysis information, HeNB control section  104  references the CSG member information stored on CSG member management section  102 , thereby determining whether or not the terminal that transmitted the release request message is stored on CSG member management section  102  as a CSG member. 
     If it is determined that the terminal is not stored as a CSG member, HeNB control section  104  determine that the terminal is a non-CSG member terminal. Using any known and ordinary release procedure and via network message generation section  107  and network interface section  108 , HeNB control section  104  then releases connection of the non-CSG member terminal with the upper layer network apparatus. 
     The upper layer network apparatus transmits a release notification message indicating the above abovementioned release. 
     Network message analysis section  106  acquires the release notification message via network interface section  108 , and analyzes the acquired release notification message. 
     Upon acquiring analysis information regarding the above-mentioned analysis from network message analysis section  106 , HeNB control section  104  determines that release at the upper layer network apparatus has been completed, and sends radio message generation section  109  a generation request for a release response message with respect to the non-CSG member terminal. 
     Radio message generation section  109  generates a release response message in accordance with the generation request for a release response message. 
     Via radio interface section  111  and antenna  112 , the generated release response message is transmitted to the non-CSG member terminal that transmitted the release request message. 
     (7) Operation for when a Change is Made to a CSG Member Terminal 
     The user managing small cell  100  registers a new CSG member terminal with small cell  100 . Specifically, CSG member management section  102  stores CSG member information regarding the new CSG member terminal. In this context, conceivable circumstances where a new CSG member terminal would be registered may include cases where a terminal for use in a home or an office is newly purchased or purchased for replacement, and so forth. 
     HeNB control section  104  acquires from CSG member management section  102  the CSG member information regarding the new CSG member terminal. HeNB control section  104  references the acquired CSG member information, and instructs terminal proxy function section  105  to update CSG member information. In so doing, if the CSG member terminals are to be updated partially, HeNB control section  104  issues an instruction to update the CSG member information with just the newly added CSG member terminal. However, this is by no means limiting, and an instruction may instead be issued in such a manner as to update the CSG member information of all CSG member terminals including the newly added CSG member terminal. 
     In accordance with the above-mentioned update instruction, terminal proxy function section  105  requests network message generation section  107  to generate an update message for updating the registered CSG member terminals. 
     Network message generation section  107  generates an update message for the CSG member terminals in accordance with the above-mentioned request. 
     The generated update message is transmitted to the upper layer network apparatus via network interface section  108 . 
     Upon completing updating the CSG member terminals, the upper layer network apparatus transmits to small cell  100  a message including a parameter that is necessary in order for the updated CSG member terminals to connect with small cell  100 . 
     Small cell  100  receives the above-mentioned message via network interface section  108 . 
     Network message analysis section  106  analyzes the message received at network interface section  108 , and notifies terminal proxy function section  105  of analysis information regarding the result of the analysis. 
     From the analysis information acquired from network message analysis section  106 , terminal proxy function section  105  acquires parameter information that is necessary in order for the updated CSG member terminals to connect with small cell  100 , and notifies CSG member parameter management section  101  of the acquired parameter information. 
     If a CSG member terminal that existed before an update is deleted at CSG member management section  102 , terminal proxy function section  105  acquires information regarding the deleted CSG member terminal via HeNB control section  104 . Terminal proxy function section  105  then notifies CSG member parameter management section  101  to delete information regarding the deleted CSG member terminal. 
     Upon receiving the above-mentioned notification, CSG member parameter management section  101  deletes information regarding the deleted CSG member terminal, and manages parameter information that is necessary in order for the updated CSG member terminals to connect with small cell  100 . 
     Thus, in the present embodiment, when updating CSG member terminals, or upon activation, a message requesting an update or collective registration of the CSG member terminals is transmitted to the upper layer network apparatus. As a result, according to the present embodiment, signaling is not performed with respect to the upper layer network apparatus with every individual request from each of the CSG member terminals. This enables a reduction in signaling traffic to/from the upper layer network apparatus, thereby mitigating the processing load on the upper layer network apparatus. 
     Furthermore, in the present embodiment, a parameter that is necessary for connecting with a CSG member terminal is acquired in advance from the upper layer network apparatus prior to receiving a connection request from the CSG member terminal. Thus, according to the present embodiment, when a connection request is received from a CSG member terminal, connection with the CSG member terminal may be established more quickly than is possible with related art techniques. 
     In the present embodiment, a message requesting an update or collective registration of CSG member terminals is transmitted to the upper layer network apparatus when updating CSG member terminals, or upon activation. However, the claimed invention is by no means limited as such, and a message requesting an update or collective registration may be transmitted to the upper layer network apparatus at any given time, such as at predetermined time intervals and/or the like. 
     The disclosure of the specification, drawings, and abstract of Japanese Patent Application No. 2010-228720 filed on Oct. 8, 2010, is hereby incorporated by reference in its entirety. 
     INDUSTRIAL APPLICABILITY 
     A small cell or signaling method according to the claimed invention is suitable for establishing and releasing connection with a terminal within a limited area, such as a home or an office. 
     REFERENCE SIGNS LIST 
     
         
           100  Small cell 
           101  CSG member parameter management section 
           102  CSG member management section 
           103  CSG member connection state management section 
           104  HeNB control section 
           105  Terminal proxy function section 
           106  Network message analysis section 
           107  Network message generation section 
           108  Network interface section 
           109  Radio message generation section 
           110  Radio message analysis section 
           111  Radio interface section 
           112  Antenna