JP4792512B2 - User terminal, radio communication system, and method - Google Patents

Description

  The present invention relates to a wireless communication system, and more particularly to a user terminal and a base station.

  Consider a mobile station device (user terminal) that can be used while switching between a plurality of wireless communication systems. In a radio communication system to which the mobile station apparatus is applied, a plurality of radio communication systems are deployed. The plurality of wireless communication systems are connected via a network.

  For example, the wireless communication system A and the wireless communication system B exist, the wireless communication system A can communicate with the wireless communication method A, and the wireless communication system B can communicate with the wireless communication method B. The wireless communication system A and the wireless communication system B are connected via a network. The base stations A and B included in the wireless communication systems A and B cooperate with each other to prompt the mobile station device to switch to the wireless communication system A or B.

  As an example, a case where the service area of the wireless communication system A is wider than the service area of the wireless communication system B and the communication speed of the wireless communication system A is slower than the communication speed of the wireless communication system B will be described. The mobile station device makes a call and connects to the base station to perform data communication. For example, the mobile station apparatus makes a call with priority to the base station A of the wireless communication system A. Then, when the base station B of the wireless communication method B exists in the vicinity of the base station A, the base station A urges the mobile station device to connect to the base station B. The mobile station device connects to the base station B. After making a call to the base station A and connecting to the base station A, the mobile station apparatus reduces the probability of connection failure due to a narrow service area when connecting to the base station. it can. In addition, when the mobile station apparatus performs communication using a wireless communication method with a high communication speed, it is possible to perform efficient communication and increase the data communication capacity of the entire network.

  As a method for switching between a plurality of wireless communication systems, there is a method called fast redirection (see, for example, Non-Patent Document 1).

  In the Fast redirection scheme, a case where the mobile station apparatus has both Long Term Evolution (LTE) and Universal Mobile Telecommunications System (UMTS) communication schemes will be described. The mobile station device calls and connects to a UMTS base station. The mobile station apparatus reports a wireless communication system supported by the mobile station apparatus together with a connection request to the base station of the UMTS. Since the UMTS base station and the LTE base station are connected via a network, the LTE base station is located in the vicinity of the UMTS base station when the LTE base station is located. A base station can be detected.

  A base station of UMTS is connected to the mobile station when the LTE system is included in the wireless communication system supported by the mobile station apparatus and the LTE base station is located in the vicinity of the base station of the UMTS. To refuse. Then, the UMTS base station notifies the mobile station apparatus of information on the center frequency of the transmission band of the LTE base station located in the vicinity. The mobile station apparatus detects the LTE base station based on the center frequency notified by the UMTS base station. The mobile station apparatus then connects to an LTE base station and starts communication.

3GPP TS 25.331 V8.5.0, Dec. 2008

  In the fast redirection scheme, the UMTS base station notifies the mobile station apparatus of the center frequency of the transmission band of the LTE base station. Then, the mobile station apparatus connects to the LTE base station based on the center frequency notified by the UMTS base station.

  Since the UMTS base station only notifies the center frequency of the transmission band of the LTE base station located around the UMTS base station, the mobile station apparatus notified of the center frequency surely There is no guarantee that the station can be connected.

  In particular, in wireless communication, the communication area changes depending on the radio wave propagation environment, so even if the mobile station device is notified of the center frequency of the LTE base station from the UMTS base station, it is not possible to actually detect the LTE base station. There is sex. If the LTE base station cannot be detected, connection cannot be established.

  When the LTE base station cannot be detected, the mobile station apparatus performs an operation to connect to the UMTS base station again. In the connection operation to the UMTS base station again, the mobile station apparatus may be notified of the center frequency of the LTE base station again from the UMTS base station. When the center frequency of the LTE base station is notified again from the UMTS base station, the mobile station apparatus may not be able to connect to the LTE base station again. Even if the center frequency of the LTE base station is notified from the UMTS base station, if the connection with the LTE base station cannot be established, the start of communication is greatly delayed.

  Therefore, the present invention has been made in view of the above-described problems, and an object of the present invention is to provide a user terminal, a base station, and a method capable of reducing connection delay in the user terminal.

This user terminal
A user capable of wireless communication by switching a plurality of wireless communication systems including a first wireless communication system capable of communication by the first wireless communication method and a second wireless communication system capable of communication by the second wireless communication method A terminal,
A first base station of the first wireless communications system, and a connection processing unit that performs connection processing by switching between the second base station of the second radio communication system,
A wireless communication method notification unit for notifying the first base station that has undergone connection processing by the connection processing unit, a wireless communication method in which the user terminal can communicate;
A connection that makes a connection request to the second base station based on the information of the second base station that is notified as a response to the wireless communication method that can be communicated by the user terminal notified by the wireless communication method notification unit A request section;
And a history recording unit that records a history of connection is performed between the first base station by the connection processing unit,
The connection request unit, if it can not connect with the second base station by the connection processing unit, connected between the first base station is performed which is recorded in the history recording unit The connection request unit obtains the number of times of connection within the predetermined time in the past after the connection request is made to the second base station by the connection request unit. A connection request to the first base station is set when the connection request to the first base station is not greater than a predetermined threshold, and the connection request to the first base station is performed when the number of times of the connection is greater than a predetermined threshold Is set to notify the wireless communication method notification unit that the user terminal can communicate with the first wireless communication system .

This wireless communication system
A user capable of wireless communication by switching a plurality of wireless communication systems including a first wireless communication system capable of communication by the first wireless communication method and a second wireless communication system capable of communication by the second wireless communication method A wireless communication system having a terminal and a first base station that performs wireless communication with the user terminal ,
The first base station is
A base station connection processing unit that performs connection processing with the user terminal;
Based on the second wireless communication system which is notified as a communicable wireless communication method by a user terminal connection processing is performed by the base station connection processing section, the second installed in the periphery of the first base station A base station information acquisition unit for acquiring information of a second base station of the wireless communication system of
A base station information notifying unit for notifying the user terminal of the information on the second base station acquired by the base station information acquiring unit;
A base station history recording unit that records a history of receiving a connection request from the user terminal,
The base station connection processing unit receives a connection start request from the user terminal based on a history of receiving a connection request from the user terminal recorded in the base station history recording unit . The number of receptions within a time is obtained, and when the number of receptions is greater than a predetermined threshold, it is determined that the connection with the first base station is continued, and when the number of receptions is smaller than the predetermined threshold, the first It is determined that the connection with the base station is not continued,
The base station information notifying unit notifies the user terminal of the information on the second base station when the base station connection processing unit determines that the connection of the first base station is not continued,
The user terminal is
A user terminal connection processing unit that performs connection processing by switching between the first base station of the first wireless communication system and the second base station of the second wireless communication system;
A wireless communication method notification unit for notifying the first base station that has undergone connection processing by the user terminal connection processing unit, a wireless communication method in which the user terminal can communicate;
A connection that makes a connection request to the second base station based on the information of the second base station that is notified as a response to the communicable wireless communication method of the user terminal notified by the wireless communication method notification unit A request section;
A user terminal history recording unit for recording a history of connection with the first base station by the user terminal connection processing unit;
Have
The connection request unit is connected to the first base station recorded in the user terminal history recording unit when the user terminal connection processing unit cannot connect to the second base station. Based on the connection history, the connection request unit obtains the number of times the connection request has been made within a predetermined time in the past since the connection request was made to the second base station. The connection request to the first base station is set when the number of connection times is not greater than a predetermined threshold value, and the first base station is set when the number of connection times is greater than the predetermined threshold value. Is set to notify the wireless communication method notifying unit that the user terminal can communicate with the first wireless communication system.

This method
A user capable of wireless communication by switching a plurality of wireless communication systems including a first wireless communication system capable of communication by the first wireless communication method and a second wireless communication system capable of communication by the second wireless communication method A terminal method,
A first base station of said first radio communication system, a connection processing step of performing connection processing by switching between the second base station of the second radio communication system,
A wireless communication method notifying step of notifying the first base station that has undergone the connection processing in the connection processing step of a wireless communication method in which the user terminal can communicate;
A connection for making a connection request to the second base station based on the information of the second base station notified as a response to the communicable wireless communication method of the user terminal notified in the wireless communication method notification step A request step;
And a history recording step of recording the history of connection is performed between the first base station by said connection processing step,
And in the connection request step, if it can not connect with the second base station by the connection processing step, the connection between the first base station is performed which is recorded by the history recording step The number of times of connection within the predetermined time in the past after the connection request is made to the second base station by the connection request step is determined based on the history of the connection, and the number of times of connection is predetermined. A connection request to the first base station is set when the connection request to the first base station is not greater than a predetermined threshold, and the connection request to the first base station is performed when the number of times of the connection is greater than a predetermined threshold Is set to notify the wireless communication method notification unit that the user terminal can communicate with the first wireless communication system .

  According to the disclosed user terminal, base station, and method, connection delay in the user terminal can be shortened.

It is explanatory drawing which shows the environment where the some radio | wireless communications system according to a present Example coexists. It is a functional block diagram which shows the radio | wireless network control apparatus, base station apparatus, and user terminal according to a present Example. It is a flowchart which shows operation | movement of the radio | wireless communications system according to a present Example. It is a flowchart which shows operation | movement of the radio | wireless communications system according to a present Example. It is a functional block diagram which shows the radio | wireless network control apparatus, base station apparatus, and user terminal according to a present Example. It is a flowchart which shows operation | movement of the radio | wireless communications system according to a present Example. It is a flowchart which shows operation | movement of the radio | wireless communications system according to a present Example. It is a functional block diagram which shows the radio | wireless network control apparatus, base station apparatus, and user terminal according to a present Example. It is a flowchart which shows operation | movement of the radio | wireless communications system according to a present Example. It is a flowchart which shows operation | movement of the radio | wireless communications system according to a present Example.

Next, the form for implementing this invention is demonstrated, referring drawings based on the following Examples.
In all the drawings for explaining the embodiments, the same reference numerals are used for those having the same function, and repeated explanation is omitted.

<First embodiment>
<Wireless communication system>
FIG. 1 shows a radio network controller (RNC) 400, a base station (BS: Base Station) 300, a base station (eNB: eNodeB) 500, and a user terminal (UE: UE) according to the present embodiment. User Equipment) 200 is shown.

  The environment to which the present wireless network control device 400, the base stations 300 and 500, and the user terminal 200 are applied is an environment in which a plurality of different wireless communication systems are mixed. The wireless communication system includes a W-CDMA wireless communication system and an Evolved UTRA and UTRAN wireless communication system. The Evolved UTRAN and UTRAN wireless communication system is sometimes referred to as Long Term Evolution (LTE) or Super 3G (Super 3G). The wireless communication system may include Mobile WiMAX (Worldwide Interoperability for Microwave Access) compliant with IEEE802.16e, CDMA2000 1xEV-DO in 3GPP2, and UMB (Ultra Mobile Broadband).

In this embodiment, as an example, a case will be described in which a plurality of wireless communication systems include a system to which the WCDMA scheme is applied and a system to which the LTE scheme is applied. When a plurality of wireless communication systems include a system to which the WCDMA system is applied and a system to which the LTE system is applied, a service of the system to which the WCDMA system is applied for a while after the LTE system is applied The area is wider than the service area of the system to which the LTE method is applied. Also, the transmission rate of a system to which the LTE scheme is applied is higher than the transmission rate of a system to which the WCDMA scheme is applied.

A system to which the W-CDMA system is applied (hereinafter referred to as “first system”) includes a base station 300 (300 ₁ , 300 ₂ ) and a radio network controller 400.

Base station 300 is connected to radio network control apparatus 400, and radio network control apparatus 400 is connected to core network 700. Base stations 300 ₁ and 300 ₂ cover cells 350 ₁ and 350 ₂ , respectively. Further, in FIG. 1, the radio network controller 400 to the base station 300 ₁ and 300 ₂ of the two are connected, may be a single, or may be three or more. In addition, although one wireless network control device 400 is illustrated in FIG. 1, two or more wireless network control devices 400 may be provided.

  The Evolved UTRA and UTRAN wireless communication system (hereinafter referred to as “second system”) includes a base station 500 and an access gateway 600.

  Base station 500 is connected to access gateway 600, and access gateway 600 is connected to core network 700. Base station 500 covers cell 550. Access gateway 600 may also be referred to as a mobility management entity / serving gateway (MME / SGW). In FIG. 1, one base station 500 is connected to the access gateway 600, but two or more base stations 500 may be used. In addition, although one access gateway 600 is illustrated in FIG. 1, two or more access gateways may be used.

In FIG. 1, a user terminal 200 is depicted. The user terminal 200 performs radio communication with the base stations 300 (300 ₁ , 300 ₂ ) in the cells 350 (350 ₁ , 350 ₂ ) using the W-CDMA scheme. In addition, the user terminal 200 performs radio communication with the base station 500 using the Evolved UTRA and UTRAN scheme in the cell 550. In other words, the user terminal 200 is a dual mode terminal. The dual mode terminal can communicate with an existing wireless communication system, for example, a W-CDMA system, and a newly introduced wireless communication system, for example, an LTE system. Although one user terminal 200 is illustrated in FIG. 1, two or more user terminals may be provided.

  The user terminal 200 according to the present embodiment switches wireless communication systems to be connected and performs wireless communication with the corresponding base station. In this embodiment, as an example, a case where wireless communication is performed by switching between the first system and the second system will be described. Specifically, the user terminal 200 switches the base station to be connected between the base station 300 of the first system and the base station 500 of the second system.

  FIG. 2 is a functional block diagram showing the radio network controller 400, the base stations 300 and 500, and the user terminal 200 according to the present embodiment.

  In FIG. 2, the access gateway 600 and the core network 700 shown in FIG. 1 are omitted for simplification of description. In addition, although two base stations 300 are depicted in FIG. 1, one base station 300 is depicted in FIG. 2 in order to perform the same operation.

<Wireless network control device>
Radio network control apparatus 400 includes base station information notification section 402 and storage section 404. The radio network controller 400 connects the first system and the second system. Specifically, a connection is made between the base station 300 of the first system to which the W-CDMA scheme is applied and the base station 500 of the second system to which the Evolved UTRA and UTRAN scheme is applied. Actually, the radio network controller 400 is connected to the base station 500 via the core network 700 and the access gateway 600.

  The storage unit 404 stores information regarding the base stations 300 and 500. The information includes the installation location and the center frequency of the transmission band of the base station 500.

  The base station information notification unit 402 is connected to the storage unit 404 and responds with information on the base stations 500 installed around the base station 300 in response to a request from the base station 300. It is assumed that the base station 500 installed in the vicinity of the base station 300 can receive the downlink signal from the base station 500 when the user terminal 200 prompted to connect to the base station 500 by the base station 300 Base stations installed in the coverage area are included. For example, the base station information notification unit 402 sets the base station 500 to be notified to the base station 300 based on the installation position of the base station 300, the installation position of the base station 500, and the cell radius of the base station 500. . Furthermore, the base station 500 that notifies the base station 300 based on the position of the user terminal 200 may be set.

<Base station of the first system>
The base station 300 includes a transmission / reception unit 302, a communication control unit 304, a transmission / reception data processing unit 306, and a communication history recording unit 308. The communication control unit 304 includes a connection start request reception number acquisition unit 3042 and a connection base station setting unit 3044.

  The transmission / reception unit 302 transmits a downlink signal to the user terminal 200. The downlink signal includes data and communication control information. The communication control information may include a common pilot channel (CPICH). The user terminal 200 calculates downlink radio quality using the common pilot channel. The calculation of the downlink radio quality may include obtaining received power of a desired wave and an interference wave. The user terminal 200 selects the base station 300 that transmits the connection start request based on the downlink radio quality. Also, the transmission / reception unit 302 receives an uplink signal from the user terminal 200 and inputs the received signal to the communication control unit 304. The uplink signal includes data and communication control information.

  The communication control unit 304 is connected to the transmission / reception unit 302 and inputs data and communication control information input by the transmission / reception unit 302 to the transmission / reception data processing unit 306 and the communication history recording unit 308, respectively.

  The connection start request reception count acquisition unit 3042 acquires the connection start request reception count M1 from the user terminal 200. For example, the connection start request reception count acquisition unit 3042 refers to the communication history recording unit 308 and has received a connection start request from the user terminal 200 within the past T1 hours from the date and time when the connection start request is received from the user terminal 200. Get the count M1. Then, the connection start request reception count acquisition unit 3042 inputs the number M1 of reception of the connection start request to the connection base station setting unit 3044. For example, T1 is set based on a delay time allowed as a connection time.

  The connection base station setting unit 3044 is connected to the connection start request reception number acquisition unit 3042, and sets a base station to be connected based on the number M1 of reception of the connection start request input by the connection start request reception number acquisition unit 3042. To do. The connection base station setting unit 3044 sets the base station 300 as a base station to which the base station 300 is connected when the number M1 of reception of the connection start request is larger than the predetermined number M. The predetermined number M is set based on the number of times that the user terminal 200 is allowed to connect to the base station 500 of the second system.

  The transmission / reception data processing unit 306 is connected to the communication control unit 304. The transmission / reception data processing unit 306 processes the data input by the communication control unit 304. Further, the transmission / reception data processing unit 306 generates a downlink signal to be transmitted to the user terminal 200. The downlink signal includes data and communication control information. Specifically, the downlink signal includes control information for refusing connection with the base station 300 and information on the base stations 500 installed around the base station 300. The information of the base station 500 includes information on the center frequency of the transmission band of the base station 500.

  The communication history recording unit 308 records a communication history for each user terminal 200 that has received the connection start request. The communication history includes the date and time when the connection start request is received from the user terminal 200 and the identification number of the user terminal 200.

<Base station of second system>
Base station 500 includes transmission / reception unit 502, communication control unit 504, and transmission / reception data processing unit 506.

  The transmission / reception unit 502 transmits a downlink signal to the user terminal 200. The downlink signal includes data and communication control information. The communication control information may include a synchronization channel (SCH). The transmission / reception unit 502 maps the synchronization channel to the frequency band in the central part of the transmission frequency band of the base station 500 and transmits it. The user terminal 200 searches for a synchronization channel transmitted from the base station 500, and synchronizes with each base station based on the synchronization channel.

  Further, the transmission / reception unit 502 receives an uplink signal from the user terminal 200 and inputs the received signal to the communication control unit 504. The uplink signal includes data and communication control information.

  The communication control unit 504 is connected to the transmission / reception unit 502 and inputs data and communication control information input by the transmission / reception unit 502 to the transmission / reception data processing unit 506.

  The transmission / reception data processing unit 506 is connected to the communication control unit 504. The transmission / reception data processing unit 506 processes the data input by the communication control unit 504. Further, the transmission / reception data processing unit 506 generates a downlink signal to be transmitted to the user terminal 200. The downlink signal includes data and communication control information.

<User terminal>
The user terminal 200 includes a transmission / reception unit 202, a communication control unit 204, a transmission / reception data processing unit 206, and a communication history recording unit 208. The communication control unit 204 includes a wireless communication method notification unit 2041, a connection processing unit 2042, and a connection procedure number acquisition unit 2044.

  The transmission / reception unit 202 receives a downlink signal from the base station 300 or 500 and inputs the downlink signal to the communication control unit 204. Further, the transmission / reception unit 202 transmits an uplink signal to the base station 300 or 500 in accordance with control by the communication control unit 204. The uplink signal includes data and / or communication control information. In addition, the transmission / reception unit 202 switches between the first system and the second system according to control by the communication control unit 204. The transmission / reception unit 202 performs connection processing with the base station 300 when performing communication with the first system. For example, the transmission / reception unit 202 receives a common pilot channel. Then, a connection start request is transmitted to the base station 300 selected based on the downlink radio quality.

  In addition, the transmission / reception unit 202 performs connection processing with the base station 500 when performing communication with the second system. For example, the transmission / reception unit 202 searches for a synchronization channel transmitted from the base station 500 based on the center frequency of the transmission band of the base station 500 notified by the base station 300, and synchronizes with the base station 500. take. Then, the transmission / reception unit 202 transmits a connection start request to the base station 500.

  The communication control unit 204 is connected to the transmission / reception unit 202, and receives the data and communication control information included in the downlink signal from the base station 300 or 500 input by the transmission / reception unit 202, the transmission / reception data processing unit 206 and the communication history, respectively. Input to the recording unit 208.

  The wireless communication method notification unit 2041 holds a wireless communication method with which the user terminal 200 can communicate, and transmits the base station 300 that has been connected to the user terminal 200 to the base station 300 through the transmission / reception unit 202. The wireless communication method in which the user terminal 200 can communicate is notified. For example, the wireless communication method notification unit 2042 notifies the first system and / or the second system as a wireless communication method with which the user terminal 200 can communicate.

  The connection procedure number acquisition unit 2044 acquires the number N1 of the number of times of performing the connection procedure to the base station 300 of the first system. The number of times of performing the connection procedure may be the number of times of transmitting the connection start request. For example, the connection procedure number acquisition unit 2044 refers to the communication history recording unit 208, and when the user terminal 200 cannot connect to the base station 500 of the second system, the connection procedure number acquisition unit 2044 The number N1 of the number of times of performing the connection procedure to the base station 300 of the first system is acquired within the time T2. The connection procedure number acquisition unit 2044 inputs the number N1 of connection procedures to the base station 300 of the first system to the connection processing unit 2042. For example, T2 is set based on a delay time allowed as a connection time.

  The connection processing unit 2042 is connected to the wireless communication method notification unit 2041 and the connection procedure number acquisition unit 2044, and performs control to switch between the first system and the second system. The connection processing unit 2042 sets a base station to be connected based on the number N1 of connection procedures to the base station 300 of the first system input by the connection procedure number acquisition unit 2044. The connection processing unit 2042 sets the base station 300 of the first system as a base station to be connected when the number N1 of connection procedures to the base station 300 of the first system is larger than the predetermined number N. The predetermined number N is set based on the number of times that the user terminal 200 is allowed to connect to the base station 300 of the first system. In other words, the predetermined number N is set based on the number of times that the user terminal 200 is allowed as the number of times that the connection to the base station 500 of the second system has failed.

  The connection processing unit 2042 records in the communication history recording unit 208 the date and time when the connection procedure was performed on the base station 300 of the first system. The date and time when the connection start request is transmitted to the base station 300 of the first system may be used. Further, the connection processing unit 2042 records the date and time when the connection procedure was performed with the base station 500 of the second system in the communication history recording unit 208. The date and time when the connection start request is transmitted to the base station 500 of the second system may be used.

  The transmission / reception data processing unit 206 is connected to the communication control unit 204. The transmission / reception data processing unit 206 processes the data input by the communication control unit 204. In addition, the transmission / reception data processing unit 206 generates an uplink signal to be transmitted to the base station 300 or 500. The uplink signal includes data and communication control information. The communication control information includes a communication start request.

  The communication history recording unit 208 records a communication history for each base station to which the user terminal 200 has transmitted a connection start request. The communication history includes the date and time when the connection procedure was performed for the base station 300 of the first system and the date and time when the connection procedure was performed for the base station 500 of the second system.

<Operation of this wireless communication system>
3 and 4 are flowcharts showing communication control processing in the wireless communication system.

  The user terminal 200 transmits a connection start request to the base station 300 (step S302). The user terminal 200 calculates downlink radio quality using the common pilot channel. Then, the user terminal 200 selects the base station 300 that transmits the connection start request based on the downlink radio quality. The transmission / reception data processing unit 206 generates a connection start request and inputs it to the communication control unit 204. The communication control unit 204 inputs the connection start request input by the transmission / reception data generation unit 206 to the transmission / reception unit 202. The transmission / reception unit 202 transmits a connection start request to the base station 300 according to control by the communication control unit 204.

  When transmitting the connection start request, the user terminal 200 transmits information for identifying the capability of the user terminal 200 (hereinafter referred to as user terminal capability identification information) (step S304). The user terminal capability identification information includes information indicating that the user terminal 200 can communicate with the first and second systems. The wireless communication method notification unit 2041 generates user terminal capability identification information and inputs the user terminal capability identification information to the transmission / reception unit 202. The transmission / reception unit 202 transmits the user terminal capability identification information input by the wireless communication method notification unit 2041 to the base station 300.

  For example, the user terminal 200 transmits user terminal capability identification information when performing location registration. For example, the user terminal 200 transmits user terminal radio capability (UE Radio Capability) and the like. The base station 300 acquires the capability of the user terminal 200 by the UE Radio Capability. Based on the terminal capability identification information, the base station 300 can determine whether or not the user terminal 200 is a dual mode terminal that can support both the first and second systems.

  Note that the terminal capability identification information is based on terminal information such as an international mobile station equipment identifier software version number (IMEISV) notified from the user terminal 200 to the core network 700. And may be notified from the core network 700 to the base station 300. IMEISV is a 16-digit number defined in the 3GPP standard. By IMEISV, the user terminal 200 can be uniquely identified and the type of the user terminal 200 can be determined.

  The user terminal 200 records the date and time when the connection is started to the base station 300 of the first system (step S306). The communication control unit 204 records the date and time when the connection start request is transmitted to the base station 300 in the communication history recording unit 208.

  When receiving the connection start request from the user terminal 200, the base station 300 acquires the number M1 of times the connection start request is received from the user terminal 200 within the past T1 hours from the reception date and time (step S308). When the base station 300 receives a connection start request from the user terminal 200, the connection start request reception count acquisition unit 3042 refers to the processing history for each user terminal stored in the communication history recording unit 308, and The number M1 of reception of connection start requests from the user terminal 200 is obtained within the past T1 hours from the reception time of the start request.

  The base station 300 determines whether or not the number M1 of reception times of the connection start request from the user terminal 200 obtained in step S308 is larger than M. The connection base station setting unit 3044 determines whether or not the number M1 of receptions of connection start requests from the user terminal 200 is a value greater than M.

  When it is determined that the number M1 of reception of connection start requests from the user terminal 200 is larger than M (step S310: YES), the base station 300 of the first system is set to connect to the user terminal 200. Is performed (step S312). The connection base station setting unit 3044 performs connection setting with the user terminal 200 when the reception count M1 of the connection start request from the user terminal 200 is larger than M. When the number M1 of connection start request receptions is larger than M, the user terminal 200 receives the second base station 500 more than M times within the past T1 time from the connection start request reception time. It is assumed that the connection with is failed. Therefore, since it is assumed that there is a high possibility of failure even when attempting to connect to the base station 500 of the second system again, a setting to connect to the base station 300 is performed. Also, from the viewpoint of connection delay, it is preferable to connect to the base station 300 rather than prompting the second system to connect to the base station 500 again.

  When it is determined that the number M1 of reception of the connection start request from the user terminal 200 is not a value larger than M (step S310: NO), the base station 300 asks the radio network control device 400 of the base station 300. Information on the base station 500 of the second system installed in the vicinity is requested (step S314). When the connection start request reception count M1 from the user terminal 200 is not a value larger than M, the connection base station setting unit 3044 is connected to the radio network control device 400 with the second base station 300 installed around the base station 300. Request information of the base station 500 of the system. When the number M1 of reception of connection start requests from the user terminal 200 is M or less, it is assumed that the connection to the base station 500 of the second system may be successful. Further, it is assumed that the connection delay is still in an allowable range. From the viewpoint of transmission speed, it is preferable to prompt the second system to connect to the base station 500 again.

  The base station 300 is a second system installed around the base station 300 included in the control information including information for refusing the connection with the base station 300 to the user terminal 200 and the response to the request in step S314. The base station 500 information is transmitted (step S316). When the connection base station setting unit 3044 receives a response including information on the base station 500 of the second system installed around the base station 300 from the radio network control device 400, the connection base station setting unit 3044 sends the response to the transmission / reception data processing unit 306. Command to generate control information including information for refusing the connection with the base station 300. The connected base station setting unit 3044 transmits the control information generated by the transmission / reception data processing unit 306 and the information of the base station 500 of the second system installed around the base station 300 to the user terminal 200. Thus, the transceiver 302 is controlled. The information of the base station 500 of the second system includes information on the center frequency of the transmission band of the base station 500.

  The base station 300 records the date and time when the connection start request is received from the user terminal 200 and the identification number of the user terminal (step S318). The connection base station setting unit 3044 records the date and time when the connection start request is received from the user terminal 200 and the identification number of the user terminal in the communication history recording unit 308.

  The user terminal 200 detects the base station 500 of the second system based on the information of the base station 500 of the second system notified by the base station 300 (step S320). The transmission / reception unit 202 searches for a synchronization channel transmitted from the base station 500 based on the information on the center frequency of the transmission band of the base station 500 of the second system.

  The user terminal 200 can detect and connect to the base station 500 of the second system (step S322). The connection processing unit 2042 searches for a synchronization channel transmitted from the base station 500 of the second system, establishes synchronization with the base station 500 based on the synchronization channel, and transmits a connection request. Determine if you were able to.

  If it is determined that the user terminal 200 can detect and connect to the base station 500 of the second system (step S322: YES), the user terminal 200 starts communication with the base station 500 of the second system (step S322). S324).

  When the user terminal 200 cannot detect the base station 500 of the second system, or when the user terminal 200 can detect but cannot connect (step S322: NO), the user terminal 200 performs a connection procedure to the base station 500 of the second system. Record the date and time. The date and time when the search for the synchronization channel is started may be used. The connection processing unit 2042 records in the communication history recording unit 208 the date and time when the connection procedure was performed for the base station 500 of the second system.

  The user terminal 200 obtains the number N1 of times of connection with the base station 300 of the first system within the past T2. The connection procedure number acquisition unit 2044 refers to the communication history recording unit 208 and obtains the number N1 of connections made with the base station 300 of the first system within the past T2 hours.

  The user terminal 200 determines whether the number N1 of performing the connection procedure to the base station 300 of the first system is a value greater than N (step S330). The connection procedure number acquisition unit 2044 determines whether the number N1 of connection procedures to the base station 300 of the first system is a value greater than N.

  When the number N1 of connection procedures to the base station 300 of the first system is not a value larger than N (step S330: NO), the process returns to step S302. The user terminal 200 transmits a connection start request again to the base station 300 of the first system. If the number N1 of connection procedures to the base station 300 of the first system is not a value larger than N, it is assumed that the connection to the base station 500 of the second system may be successful. If the number N1 of connection procedures to the base station 300 of the first system is not greater than N, the number of times the connection procedure to the base station 500 of the second system has failed is not greater than N. By making a connection request to the base station 500 of the second system again, it is assumed that the connection to the base station 500 may be successful. Encouraging the connection of the second system to the base station 500 is also preferable from the viewpoint of transmission speed.

  When the number N1 of connection procedures to the base station 300 is greater than N (step S330: YES), the user terminal 200 transmits a connection start request to the base station 300 of the first system (step S332). ). The connection processing unit 1042 transmits a connection start request to the base station 300 of the first system. Then, the connection processing unit 2042 notifies the wireless communication method notification unit 2041 that it is connected to the first system. If the number N1 of connection procedures to the base station 300 of the first system is a value larger than N, the user terminal 200 will receive the base of the second system more than N times within the past T2 hours. It is assumed that the connection with the station 500 has failed. Therefore, since it is assumed that there is a high possibility of failure even when attempting to connect to the base station 500 of the second system again, it is prompted to connect to the base station 300.

  When transmitting the connection start request, the user terminal 200 transmits the user terminal capability identification information of the user terminal 200 (step S334). The user terminal capability identification information includes information indicating that the user terminal 200 can communicate with the first system. The wireless communication method notification unit 2041 notifies that the user terminal 200 can communicate with the first system. Even if the user terminal 200 can communicate with the first and second systems, the user terminal 200 can be surely communicated with the base station 300 of the first system by notifying that the communication is possible with the first system. Connection processing can be performed between them.

  Communication is started between the user terminal 200 and the base station 300 of the first system (step S336).

  According to the present embodiment, the user terminal 200 preferentially connects to the first system. Since the first system has a larger service area than the second system, the possibility of connection failure can be reduced by preferentially connecting to the first system.

  According to the present embodiment, the user terminal 200 is prompted to connect to the base station 500 of the second system from the base station 300 after connecting to the base station 300 of the first system. By connecting to the base station 500 of the second system, communication can be performed at a higher transmission rate than the first system.

  According to the present embodiment, the base station 300 of the first system transmits to the user terminal 200 the second system based on the number of connections between the base station 300 and the user terminal 200 during a predetermined time. It is determined whether or not the connection with the base station 500 is prompted. The number of connections between the base station 300 and the user terminal 200 during the predetermined time corresponds to the number of times that the user terminal 200 has failed to connect to the base station 500 of the second system. Therefore, when the number of connections is less than or equal to the permitted number, the connection with the base station 500 of the second system is prompted, and when the number of connections is greater than the permitted number, By not prompting the connection, it is possible to avoid further connection failure. Further, since connection failure can be avoided, connection delay can be shortened.

<Second embodiment>
<Wireless communication system>
The wireless communication system will be described with reference to FIG. 1 as in the above-described embodiment.

  FIG. 5 is a functional block diagram showing a radio network control device 400, base station devices 300 and 500, and a user terminal 200 according to the present embodiment. The radio network controller 400, the base station 500, and the user terminal 200 are the same as those in the above-described embodiment.

  In the base station 300 described with reference to FIG. 2, the connection start request reception number acquisition unit 3042 is omitted from the base station 300.

  In the wireless communication system, based on the communication history recorded in the user terminal 200, a system to which the user terminal 200 is connected is selected.

<Operation of this wireless communication system>
6 and 7 are flowcharts showing communication control processing in the wireless communication system.

  The user terminal 200 transmits a connection start request to the base station 300 (step S602). The user terminal 200 calculates downlink radio quality using the common pilot channel. Then, the user terminal 200 selects the base station 300 that transmits the connection start request based on the downlink radio quality. The transmission / reception data processing unit 206 generates a connection start request and inputs it to the communication control unit 204. The communication control unit 204 inputs the connection start request input by the transmission / reception data generation unit 206 to the transmission / reception unit 202. The transmission / reception unit 202 transmits a connection start request to the base station 300 according to control by the communication control unit 204.

  When transmitting the connection start request, the user terminal 200 transmits the user terminal capability identification information of the user terminal 200 (step S604). The wireless communication method notification unit 2041 generates user terminal capability identification information and inputs the user terminal capability identification information to the transmission / reception unit 202. The transmission / reception unit 202 transmits the user terminal capability identification information input by the wireless communication method notification unit 2041 to the base station 300. The user terminal capability identification information includes information indicating that the user terminal 200 can communicate with the first and second systems.

  The base station 300 of the first system requests the wireless network control device 400 for information on the base station 500 of the second system installed around the base station 300 (step S606). The connection base station setting unit 3044 requests the wireless network control device 400 for information on the base station 500 of the second system installed around the base station 300.

  The base station 300 is a second system installed around the base station 300 included in the control information including information for refusing the connection with the base station 300 to the user terminal 200 and the response to the request in step S606. The base station 500 information is transmitted (step S608). When the connection base station setting unit 3044 receives a response including information on the base station 500 of the second system installed around the base station 300 from the radio network control device 400, the connection base station setting unit 3044 sends the response to the transmission / reception data processing unit 306. Command to generate control information including information for refusing the connection with the base station 300. The connected base station setting unit 3044 transmits the control information generated by the transmission / reception data processing unit 306 and the information of the base station 500 of the second system installed around the base station 300 to the user terminal 200. Thus, the transceiver 302 is controlled. The information of the base station 500 of the second system includes information on the center frequency of the transmission band of the base station 500.

  The base station 300 records the date and time when the connection start request is received from the user terminal 200 and the identification number of the user terminal (step S610). The connection base station setting unit 3044 records the date and time when the connection start request is received from the user terminal 200 and the identification number of the user terminal in the communication history recording unit 308.

  The user terminal 200 detects the base station 500 of the second system based on the information of the base station 500 of the second system notified by the base station 300 (step S612). The transmission / reception unit 202 searches for a synchronization channel transmitted from the base station 500 based on the information on the center frequency of the transmission band of the base station 500 of the second system. The connection processing unit 2042 records the date and time when the search for the synchronization channel from the base station 500 of the second system is started in the transmission history recording unit 208.

  The user terminal 200 can detect and connect to the base station 500 of the second system (step S614). The connection processing unit 2042 searches for a synchronization channel transmitted from the base station 500 of the second system, synchronizes with the base station 500 based on the synchronization channel, and transmits a connection request. Determine if connection was successful.

  When it is determined that the user terminal 200 can detect and connect to the base station 500 of the second system (step S614: YES), the user terminal 200 starts communication with the base station 500 of the second system (step S614). S616).

  If the user terminal 200 cannot detect the base station 500 of the second system, or if it can detect but cannot connect (step S614: NO), the user terminal 200 again detects the base station 500 of the second system at time T3. Detection is performed (step S618). The T3 may be set in advance as a time for retrying detection of the base station 500 of the second system. The transmission / reception unit 202 searches for a synchronization channel transmitted from the base station 500 of the second system, and synchronizes with the base station 500 based on the synchronization channel. The connection processing unit 2042 records the date and time when the search for the synchronization channel from the base station 500 of the second system is started in the transmission history recording unit 208.

  The user terminal 200 can detect and connect to the base station 500 of the second system (step S620). The connection processing unit 2042 searches for a synchronization channel transmitted from the base station 500 of the second system, establishes synchronization with the base station 500 based on the synchronization channel, and transmits a connection request. Determine if it was done.

  If it is determined that the user terminal 200 can detect and connect to the base station 500 of the second system (step S620: YES), the user terminal 200 starts communication with the base station 500 of the second system (step S620). S622).

When the user terminal 200 cannot detect the base station 500 of the second system, or when the user terminal 200 can detect but cannot connect (step S620: NO), the user terminal 200 performs the connection execution count to the base station 500 of the second system. It is determined whether the number of connection executions exceeds O (step S624). The connection procedure number acquisition unit 2044 refers to the communication history recording unit 208, counts the number of detections as the number of times of connection to the base station 500 of the second system,
Input to the connection processing unit 2042. The connection processing unit 2042 determines whether or not the connection execution number input by the connection procedure number acquisition unit 2044 has exceeded O times. The O is set based on the number of times that the user terminal 200 is allowed as the number of connections to the base station 500 of the second system.

  When it is not determined that the number of connection executions exceeds O (step S624: NO), the process returns to step S618. The user terminal 200 continues to detect the base station 500 of the second system until the number of connection executions exceeds O times or the base station 500 of the second system can be connected.

  When it is determined that the number of connection implementations exceeds O (step S624: YES), the user terminal 200 transmits a connection start request to the base station 300 of the first system (step S626). The connection processing unit 2042 transmits a connection start request to the base station 300 of the first system. Then, the connection processing unit 2042 notifies the wireless communication method notification unit 2041 that it is connected to the first system. If the connection to the base station 500 of the second system cannot be established even when the number of times of connection to the base station 500 of the second system exceeds O, the connection to the base station 500 of the second system is attempted again. However, since it is assumed that there is a high possibility of failure, a setting to connect to the base station 300 is performed.

  When transmitting the connection start request, the user terminal 200 transmits the user terminal capability identification information of the user terminal 200 (step S628). The user terminal capability identification information includes information indicating that the user terminal 200 can communicate with the first system. The wireless communication method notification unit 2041 notifies that the user terminal 200 can communicate with the first system. Even if the user terminal 200 can communicate with the first and second systems, the user terminal 200 can be surely communicated with the base station 300 of the first system by notifying that the communication is possible with the first system. Connection processing can be performed between them.

  Communication is started between the user terminal 200 and the base station 300 of the first system (step S630).

  According to the present embodiment, whether or not the user terminal 200 is connected to the base station 500 of the second system is set based on the history information of the user terminal 200. The history information includes the number of times that the user terminal 200 makes a connection start request to the base station 500 of the second system. Therefore, there is no need to record history information on the base station 300 side. In the above flow, the case where the base station 300 of the first system records the communication history of the user terminal 200 has been described. However, the user apparatus 200 can select a system to be connected regardless of the communication history.

<Third embodiment>
<Wireless communication system>
The wireless communication system will be described with reference to FIG. 1 as in the above-described embodiment.

  FIG. 8 is a functional block diagram showing the radio network control device 400, the base station devices 300 and 500, and the user terminal 200 according to the present embodiment. The radio network controller 400 and the base station 500 are the same as those in the above-described embodiment.

  In the base station 300 described with reference to FIG. 2, the connection start request reception number acquisition unit 3042 is omitted from the base station 300. The user terminal 200 includes a communication quality measurement unit 2046 instead of the connection procedure number acquisition unit 2044 in the user terminal 200 described with reference to FIG.

  In this wireless communication system, the user terminal 200 measures communication quality and sets a system to which the user terminal 200 is connected based on the communication quality.

<Operation of this wireless communication system>
9 and 10 are flowcharts showing connection processing in the wireless communication system.

  The user terminal 200 measures the communication quality based on the downlink signal transmitted by the base station 300 of the first system (step S902). The communication quality measuring unit 2046 measures the communication quality based on the downlink signal. Specifically, the communication quality measurement unit 2046 performs despreading processing on the downlink signal transmitted by the base station 300 of the first system, and uses the obtained common pilot channel to perform downlink processing. Calculate communication quality. For example, the received power of the desired wave and the interference wave is obtained. The communication quality measurement unit 2046 inputs the downlink communication quality to the connection processing unit 2042.

  The user terminal 200 determines whether or not the communication quality measured in step S902 is greater than or equal to the threshold (step S904). The connection processing unit 2042 determines whether or not the communication quality input by the communication quality measurement unit 2046 is equal to or higher than a threshold value. The threshold is set based on communication quality allowed between the user terminal 200 and the base station 300 of the first system.

  When the communication quality is not equal to or higher than the threshold (step S906: NO), the user terminal 200 transmits a connection start request to the base station 300 of the first system (step S908). The connection processing unit 2042 transmits a connection start request to the base station 300 of the first system. If the communication quality with the base station 300 of the first system is less than the threshold value, it is assumed that there is a high possibility of failure even if a connection attempt to the base station 500 of the second system is attempted. Then, setting to connect to the base station 300 is performed.

  When transmitting the connection start request, the user terminal 200 transmits the user terminal capability identification information of the user terminal 200 (step S910). The user terminal capability identification information includes information indicating that the user terminal 200 can communicate with the first system. The wireless communication method notification unit 2041 notifies that the user terminal 200 can communicate with the first system. Even if the user terminal 200 can communicate with the first and second systems, the user terminal 200 can be surely communicated with the base station 300 of the first system by notifying that the communication is possible with the first system. Connection processing can be performed between them.

  Communication is started between the user terminal 200 and the base station 300 of the first system (step S912).

  When the communication quality is equal to or higher than the threshold (step S906: YES), the user terminal 200 transmits a connection start request to the base station 300 (step S914). The communication control unit 204 inputs the connection start request input by the transmission / reception data generation unit 206 to the transmission / reception unit 202. The transmission / reception unit 202 transmits a connection start request to the base station 300 according to control by the communication control unit 204.

  When transmitting the connection start request, the user terminal 200 transmits the user terminal capability identification information of the user terminal 200 (step S916). The wireless communication method notification unit 2041 generates user terminal capability identification information and inputs the user terminal capability identification information to the transmission / reception unit 202. The transmission / reception unit 202 transmits the user terminal capability identification information input by the wireless communication method notification unit 2041 to the base station 300. The user terminal capability identification information includes information indicating that the user terminal 200 can communicate with the first and second systems.

  The base station 300 requests the wireless network control device 400 for information on the base station 500 of the second system installed around the base station 300 (step S918). The connection base station setting unit 3044 requests the wireless network control device 400 for information on the base station 500 of the second system installed around the base station 300.

  The base station 300 is a second system installed in the vicinity of the base station 300 included in the control information including information for refusing the connection with the base station 300 to the user terminal 200 and the response to the request in step S918. The base station 500 information is transmitted (step S920). When the connection base station setting unit 3044 receives a response including information on the base station 500 of the second system installed around the base station 300 from the radio network control device 400, the connection base station setting unit 3044 sends the response to the transmission / reception data processing unit 306. Command to generate control information including information for refusing the connection with the base station 300. The connected base station setting unit 3044 transmits the control information generated by the transmission / reception data processing unit 306 and the information of the base station 500 of the second system installed around the base station 300 to the user terminal 200. Thus, the transceiver 302 is controlled. The information of the base station 500 of the second system includes information on the center frequency of the transmission band of the base station 500.

  The base station 300 records the date and time when the connection start request is received from the user terminal 200 and the identification number of the user terminal (step S922). The connection base station setting unit 3044 records the date and time when the connection start request is received from the user terminal 200 and the identification number of the user terminal in the communication history recording unit 308.

  The user terminal 200 detects the base station 500 of the second system based on the information of the base station 500 of the second system notified by the base station 300 (step S924). The transmission / reception unit 202 searches for a synchronization channel transmitted from the base station 500 based on the information on the center frequency of the transmission band of the base station 500 of the second system. The connection processing unit 2042 records the date and time when the search for the synchronization channel from the base station 500 of the second system is started in the transmission history recording unit 208.

  The user terminal 200 can detect and connect to the base station 500 of the second system (step S926). The connection processing unit 2042 searches for a synchronization channel transmitted from the base station 500 of the second system, establishes synchronization with the base station 500 based on the synchronization channel, and transmits a connection request. Determine if it was done.

  When it is determined that the user terminal 200 can detect and connect to the base station 500 of the second system (step S926: YES), the user terminal 200 starts communication with the base station 500 of the second system (step S926). S928).

  If the user terminal 200 cannot detect the base station 500 of the second system, or if it can detect but cannot connect (step S926: NO), the user terminal 200 again detects the base station 500 of the second system at time T3. Detecting (step S930). The transmission / reception unit 202 searches for a synchronization channel transmitted from the base station 500 of the second system, and synchronizes with the base station 500 based on the synchronization channel. The connection processing unit 2042 records the date and time when the search for the synchronization channel from the base station 500 of the second system is started in the transmission history recording unit 208.

  The user terminal 200 can detect and connect to the base station 500 of the second system (step S932). The connection processing unit 2042 searches for a synchronization channel transmitted from the base station 500 of the second system, establishes synchronization with the base station 500 based on the synchronization channel, and transmits a connection request. Determine if it was done.

  When it is determined that the user terminal 200 can detect and connect to the base station 500 of the second system (step S932: YES), the user terminal 200 starts communication with the base station 500 of the second system (step S932). S934).

When the user terminal 200 cannot detect the base station 500 of the second system, or when the user terminal 200 can detect but cannot connect (step S932: NO), the user terminal 200 performs the connection execution count to the base station 500 of the second system. It is determined whether or not the number of connection executions exceeds O (step S936). The connection procedure number acquisition unit 2044 refers to the communication history recording unit 208, counts the number of detections as the number of times of connection to the base station 500 of the second system,
Input to the connection processing unit 2042. The connection processing unit 2042 determines whether or not the connection execution number input by the connection procedure number acquisition unit 2044 has exceeded O times. The O is set based on the number of times that the user terminal 200 is allowed as the number of connections to the base station 500 of the second system.

  If it is not determined that the connection execution count has exceeded O times (step S936: NO), the process returns to step S930. The user terminal 200 continues to detect the base station 500 of the second system until the number of connection executions exceeds O times or the base station 500 of the second system can be connected.

When it is determined that the number of connection implementations exceeds O (step S936: YES), the user terminal 200 transmits a connection start request to the base station 300 of the first system (step S938). The connection processing unit 2042 transmits a connection start request to the base station 300 of the first system.
Then, the connection processing unit 2042 notifies the wireless communication method notification unit 2041 that it is connected to the first system. If the connection to the base station 500 of the second system cannot be established even when the number of times of connection to the base station 500 of the second system exceeds O, the connection to the base station 500 of the second system is attempted again. However, since it is assumed that there is a high possibility of failure, a setting to connect to the base station 300 is performed.

  When transmitting the connection start request, the user terminal 200 transmits the user terminal capability identification information of the user terminal 200 (step S940). The user terminal capability identification information includes information indicating that the user terminal 200 can communicate with the first system. The wireless communication method notification unit 2041 notifies that the user terminal 200 can communicate with the first system. Even if the user terminal 200 can communicate with the first and second systems, the user terminal 200 can be surely communicated with the base station 300 of the first system by notifying that the communication is possible with the first system. Connection processing can be performed between them.

  Communication is started between the user terminal 200 and the base station 300 of the first system (step S942).

  According to the present embodiment, the user terminal 200 can determine whether to try to connect to the second system based on the downlink communication quality. When the downlink communication quality is poor, the connection to the second system is not performed, so that the number of connection processes to the second system can be reduced. Also, the connection delay time can be shortened.

  In the embodiment described above, the communication history holding time recorded in the communication history recording units 208 and 308 may be limited, and the communication history after a preset time may be automatically deleted. By automatically deleting the communication history, the storage capacity required for the user terminal 200 and the base station 300 can be reduced.

  In the embodiment described above, the processing related to the system to which the user terminal 200 is connected may be performed by the radio network controller 400 or may be performed in the base station 500 of the second system. Further, the radio network control device 400, the base station 500 of the first system, and the base station 500 of the second system may cooperate with each other.

  According to the present embodiment, a plurality of wireless communication systems including a first wireless communication system capable of communicating by the first wireless communication method and a second wireless communication system capable of communicating by the second wireless communication method are provided. A user terminal 200 capable of wireless communication by switching is provided. The user terminal 200 switches the first base station of the first wireless communication system and the second base station 300 of the second wireless communication system to switch connection processing unit 2042 as a connection processing unit that performs connection processing. A wireless communication method notification unit 2041 as a wireless communication method notification unit for notifying the first base station 300 that has been connected by the connection processing unit, of a wireless communication method with which the user terminal can communicate, Based on the information of the second base station 500 notified as a response to the communicable wireless communication method of the user terminal 200 notified by the wireless communication method notification unit, a connection request is sent to the second base station 500. A communication processing unit 2042 as a connection request unit to be performed, and a communication history as a history recording unit that records that a connection request has been made to the second base station 500 by the connection request unit It has a recording unit 208. The connection request unit, based on the number of connection requests to the second base station 500 recorded in the history recording unit when the connection processing unit cannot connect to the second base station 500. , Whether to continue the connection request to the second base station 500, the first base station to the second wireless communication method notified as a wireless communication method that can be communicated by the user terminal Based on this, information on the second base station installed around the first base station is acquired, and the information is notified to the user terminal.

  When it is not possible to connect to the second base station 500 by determining whether to continue the connection request to the second base station 500 based on the number of connection requests to the second base station 500, the second base station 500 The number of connection requests to the base station 500 can be reduced. Since the number of connection requests to the second base station 500 can be reduced, the connection request time to the second base station 500 can be shortened. In the above-described embodiment, the case where the connection processing unit 2042 has the function of the connection processing unit and the function of the connection request unit has been described. However, the connection processing unit 2042 may be configured separately into a connection processing unit and a connection request unit.

  Further, the connection request unit determines that the communication between the user terminal 200 and the second base station 500 is impossible based on the number of connection requests in a predetermined period. It is determined not to make a connection request to the second base station 500. The connection processing unit performs a connection process with the first base station 300 when the connection request unit determines that a connection request to the second base station 500 is not performed.

  By performing a connection process with the first base station 300 based on the number of connection requests to the second base station 500, the number of connection requests to the second base station 500 increases, and the user terminal 200 When it is determined that communication between the first base station 500 and the second base station 500 is impossible, connection processing with the first base station 300 can be performed.

  Furthermore, a communication quality measuring unit that measures communication quality based on a downlink signal from the first base station 300 is provided. The wireless communication method notifying unit notifies the first base station 300 as a wireless communication method with which the user terminal 200 can communicate when the communication quality measured by the communication quality measuring unit is greater than a predetermined threshold. When the communication quality measured by the communication quality measuring unit is equal to or lower than a predetermined threshold, the first wireless communication method is notified as the wireless communication method with which the user terminal 200 can communicate.

  A communication quality measuring unit for measuring communication quality based on a downlink signal from the first base station 300, and communication with the user terminal 200 is possible when the communication quality is equal to or lower than a predetermined threshold By notifying the first wireless communication method as a simple wireless communication method, connection processing with the first base station 300 can be performed without making a connection request to the second base station 500. . When the communication quality is equal to or lower than a predetermined threshold, it is assumed that even if a connection request is made to the second base station 500, it fails. By performing a connection process with the first base station 300, the connection time between the user terminal 200 and the base station can be shortened.

According to the present embodiment, a plurality of wireless communication systems including a first wireless communication system capable of communicating by the first wireless communication method and a second wireless communication system capable of communicating by the second wireless communication method are provided. A base station 300 that performs wireless communication with a user terminal 200 that can perform wireless communication by switching is provided. The base station apparatus includes a communication control unit 304 serving as a connection processing unit that performs a connection process with the user terminal 200, and a wireless communication method that enables communication by the user terminal 200 that has undergone the connection process by the connection processing unit. As a base station information acquisition unit that acquires information of the second base station 500 of the second wireless communication system installed around the base station based on the second wireless communication method notified as A station setting unit 3044, a connected base station setting unit as a base station information notifying unit for notifying the user terminal 200 of information of the second base station 500 acquired by the base station information acquiring unit, and the user terminal 200 And a communication history recording unit 308 as a history recording unit that records that a connection request has been received. The connection processing unit determines whether to continue the connection with the base station 300 based on the number of times of receiving the connection request from the user terminal 200 recorded in the history recording unit. When the connection processing unit determines that the connection with the base station 300 is not continued, the base station information notification unit notifies the user terminal 200 of the information of the second base station 500,
When the information on the second base station is notified by the base station, the user terminal makes a connection request to the second base station.

  When it is not possible to connect to the second base station 500 by determining whether to reject the connection with the base station 300 based on the number of times of receiving the connection request from the user terminal 200, the second base station The number of connection requests to the station 500 can be reduced. Since the number of connection requests to the second base station 500 can be reduced, the connection request time to the second base station 500 can be shortened. In the embodiment described above, the case where the connected base station setting unit 3044 has the function of the base station information acquisition unit and the function of the base station information notification unit has been described. However, the connection base station setting unit 3044 may be configured separately into a base station information acquisition unit and a base station information notification unit.

  For convenience of explanation, specific numerical examples will be described to facilitate understanding of the invention. However, unless otherwise specified, these numerical values are merely examples, and any appropriate value may be used.

  Although the present invention has been described above with reference to specific embodiments, each embodiment is merely an example, and those skilled in the art will understand various variations, modifications, alternatives, substitutions, and the like. I will. For convenience of explanation, an apparatus according to an embodiment of the present invention has been described using a functional block diagram, but such an apparatus may be realized by hardware, software, or a combination thereof. The present invention is not limited to the above-described embodiments, and various variations, modifications, alternatives, substitutions, and the like are included without departing from the spirit of the present invention.

200 user terminal 202 transmitting and receiving unit 204 communication control unit 2041 radio communication system notifying unit 2042 connection processing unit 2044 access procedure count acquisition unit 2046 communication quality measurement unit 206 received data processing unit 208 a communication history recording section 300 ₍₃₀₀ 1, ₃₀₀ 2) Base Station (base station of the first system)
302 Transmission / reception unit 304 Communication control unit 3042 Connection start request reception frequency acquisition unit 3044 Connection base station setting unit 306 Transmission / reception data processing unit 308 Communication history recording unit 350 (350 ₁ , 350 ₂ ) Cell 400 Wireless network control device 402 Base station information notification Unit 404 Storage unit 500 Base station (base station of second system)
502 transmission / reception unit 504 communication control unit 506 transmission / reception data processing unit 550 cell 600 access gateway 700 core network

Claims (5)

A user capable of wireless communication by switching a plurality of wireless communication systems including a first wireless communication system capable of communication by the first wireless communication method and a second wireless communication system capable of communication by the second wireless communication method A terminal,
A first base station of the first wireless communications system, and a connection processing unit that performs connection processing by switching between the second base station of the second radio communication system,
A wireless communication method notification unit for notifying the first base station that has undergone connection processing by the connection processing unit, a wireless communication method in which the user terminal can communicate;
A connection that makes a connection request to the second base station based on the information of the second base station that is notified as a response to the wireless communication method that can be communicated by the user terminal notified by the wireless communication method notification unit A request section;
And a history recording unit which records the history of connection is performed between the first base station by the connection processing unit,
The connection request unit, if it can not connect with the second base station by the connection processing unit, connected between the first base station is performed which is recorded in the history recording unit The connection request unit obtains the number of times of connection within the predetermined time in the past after the connection request is made to the second base station by the connection request unit. A connection request to the first base station is set when the connection request to the first base station is not greater than a predetermined threshold, and the connection request to the first base station is performed when the number of times of the connection is greater than a predetermined threshold And a user terminal configured to notify the wireless communication method notification unit that the user terminal can communicate with the first wireless communication system . The user terminal according to claim 1,
When the connection request unit determines that communication between the user terminal and the second base station is impossible based on the number of connection requests in a predetermined period, the second base station Decide not to make a connection request to
The connection processing unit is a user terminal that performs a connection process with the first base station when the connection request unit determines that a connection request to the second base station is not performed. The user terminal according to claim 1,
A communication quality measuring unit for measuring communication quality based on a downlink signal from the first base station,
The wireless communication method notifying unit notifies the first base station as a wireless communication method capable of communicating with the user terminal when the communication quality measured by the communication quality measuring unit is higher than a predetermined threshold. A user terminal that notifies a communication method and notifies the first wireless communication method as a wireless communication method with which the user terminal can communicate when the communication quality measured by the communication quality measuring unit is equal to or lower than a predetermined threshold. A user capable of wireless communication by switching a plurality of wireless communication systems including a first wireless communication system capable of communication by the first wireless communication method and a second wireless communication system capable of communication by the second wireless communication method A wireless communication system having a terminal and a first base station that performs wireless communication with the user terminal ,
The first base station is
A base station connection processing unit that performs connection processing with the user terminal;
Based on the second wireless communication system which is notified as a communicable wireless communication method by a user terminal connection processing is performed by the base station connection processing section, the second installed in the periphery of the first base station A base station information acquisition unit for acquiring information of a second base station of the wireless communication system of
A base station information notifying unit for notifying the user terminal of the information on the second base station acquired by the base station information acquiring unit;
A base station history recording unit that records a history of receiving a connection request from the user terminal,
The base station connection processing unit receives a connection start request from the user terminal based on a history of receiving a connection request from the user terminal recorded in the base station history recording unit . The number of receptions within a time is obtained, and when the number of receptions is greater than a predetermined threshold, it is determined that the connection with the first base station is continued, and when the number of receptions is smaller than the predetermined threshold, the first It is determined that the connection with the base station is not continued ,
The base station information notifying unit notifies the user terminal of the information on the second base station when the base station connection processing unit determines that the connection of the first base station is not continued,
The user terminal is
A user terminal connection processing unit that performs connection processing by switching between the first base station of the first wireless communication system and the second base station of the second wireless communication system;
A wireless communication method notification unit for notifying the first base station that has undergone connection processing by the user terminal connection processing unit, a wireless communication method in which the user terminal can communicate;
A connection that makes a connection request to the second base station based on the information of the second base station that is notified as a response to the communicable wireless communication method of the user terminal notified by the wireless communication method notification unit A request section;
A user terminal history recording unit for recording a history of connection with the first base station by the user terminal connection processing unit;
Have
The connection request unit is connected to the first base station recorded in the user terminal history recording unit when the user terminal connection processing unit cannot connect to the second base station. Based on the connection history, the connection request unit obtains the number of times the connection request has been made within a predetermined time in the past since the connection request was made to the second base station. The connection request to the first base station is set when the number of connection times is not greater than a predetermined threshold value, and the first base station is set when the number of connection times is greater than the predetermined threshold value. A wireless communication system configured to make a connection request to the wireless communication system and to notify the wireless communication method notification unit that the user terminal can communicate with the first wireless communication system. A user capable of wireless communication by switching a plurality of wireless communication systems including a first wireless communication system capable of communication by the first wireless communication method and a second wireless communication system capable of communication by the second wireless communication method A terminal method,
A first base station of said first radio communication system, a connection processing step of performing connection processing by switching between the second base station of the second radio communication system,
A wireless communication method notifying step of notifying the first base station that has undergone the connection processing in the connection processing step of a wireless communication method in which the user terminal can communicate;
A connection for making a connection request to the second base station based on the information of the second base station notified as a response to the communicable wireless communication method of the user terminal notified in the wireless communication method notification step A request step;
And a history recording step of recording the history of connection is performed between the first base station by said connection processing step,
And in the connection request step, if it can not connect with the second base station by the connection processing step, the connection between the first base station is performed which is recorded by the history recording step The number of times of connection within the predetermined time in the past after the connection request is made to the second base station by the connection request step is determined based on the history of the connection, and the number of times of connection is predetermined. A connection request to the first base station is set when the connection request to the first base station is not greater than a predetermined threshold, and the connection request to the first base station is performed when the number of times of the connection is greater than a predetermined threshold And setting so as to notify the wireless communication method notification unit that the user terminal can communicate with the first wireless communication system .

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