JP2010068233A - Radio communication system, radio communication method and radio base station device - Google Patents

Abstract

An object of the present invention is to add a service to be used by handing over to an access method that supports only packet connection while one service is being used in one of the two access methods.
SOLUTION: While providing a voice call service through a 1xRTT access network to a terminal UE (sequence s101), a handover to an E-UTRAN access network (sequence s102 to 110) is performed, and a packet communication service is added. The terminal UE is provided with both voice call service and packet communication service (sequences s111 to s114).
[Selection] Figure 2

Description

  The present invention relates to a radio communication system that provides a voice call service and a packet communication service.

Recently, wireless communication systems such as mobile phone systems provide both voice call services and packet communication services.
For example, Non-Patent Document 1 describes a method of interconnecting a CDMA2000 1xRTT (hereinafter 1xRTT) mobile communication network and a CDMA2000 1x EV-DO (hereinafter EVDO) mobile communication network.

  In the system in this document, for voice / data connection by circuit switching, a mobile switching center (MSC) of a 1xRTT mobile communication network is connected to a public network (PSTN, ISDN). On the other hand, for services by packet switching, a PDSN (Packete Data Serving Node) of an EVDO mobile communication network is connected to a packet communication network outside the network such as the Internet.

  When a call is received or received by circuit switching, the terminal connects to the base station (BS) by the 1xRTT method and performs a service by circuit switching. On the other hand, when a service is transmitted or received by packet switching, the terminal connects to the EVDO base station by the EVDO method and performs the service by packet switching.

  Further, for example, in Non-Patent Document 2, an EPC (Evolved Packet Core) network that accommodates E-UTRAN (Evolved Universal Terrestrial Radio Access Network) corresponding to the 3.9th generation and a 1xRTT / EVDO mobile communication network are interconnected. The method is described. EPC is a network that has only packet connections.

  According to Non-Patent Document 1 and Non-Patent Document 2, service voice calls using circuit switching are performed using 1xRTT in an "integrated" mobile communication network that provides E-UTRAN (LTE), 1xRTT, and EVDO. To do. In particular, at the initial LTE introduction stage, we want to make use of network resources in circuit switching, so we want to use 1xRTT for voice call services.

  However, when a 1xRTT circuit-switched connection is being performed and a packet connection service is to be implemented, it is necessary to add a connection to E-UTRAN or EVDO. For this purpose, the terminal must be connected using two different access methods at the same time, and has a radio transmission / reception unit and a signal processing unit of different systems and operates simultaneously with 1xRTT.

  As described above, simultaneous communication using the two access methods causes problems such as an increase in the load on the processing control unit, a complicated process control, and an increase in current consumption, which are difficult to realize. In addition, one terminal occupies two systems, and the utilization efficiency of radio resources is poor when viewed from the whole system.

  On the other hand, in Patent Document 1, for example, one mobile communication network is provided with two systems of second generation (GSM) and third generation (UMTS), and the connection has already been established by circuit switching. When a packet switched connection becomes necessary (or vice versa), the terminal informs the mobile communication network that a packet switched connection (or circuit switched connection) is necessary, and the mobile communication network Describes a system that enables connection and handover (simultaneous connection between a circuit switching and a packet switching) in a mobile communication network (handover) and enables simultaneous connection between a circuit switching and a packet switching. . According to this, since it is not necessary to make a radio | wireless part into a double structure and only one system is utilized, the utilization efficiency of a radio | wireless resource is also good.

  However, Patent Document 1 discloses that when a circuit-switched connection is already performed in a second-generation base station, when a packet-switched connection is added, a third-generation base station that is a handover destination is connected to the circuit-switched connection. And support for both packet-switched connections. Therefore, the present invention cannot be applied to a mobile communication network configured by a 1xRTT system having only circuit switched connection and an EVDO system having only packet switched connection. This is because when a packet connection is added in the state where a circuit switched connection is performed using the 1xRTT method, even if a handover is performed to the EVDO method, a packet switched connection cannot be added to the circuit switched connection using the destination method. It is.

Recently, development of a system that employs the LTE (Long Term Evolution) system is underway, but the LTE system supports only packet-switched connections, similar to the EVDO system. For this reason, in the technology of Patent Document 1, it is not possible to add a service by handing over from the third generation method that uses one service to the LTE method (EVDO method).
3GPP2 A.S0008-C_v1.0 3GPP TS23.402 v8.2.0 JP 2004-236314 A

  In conventional wireless communication systems, there is a problem in that it is not possible to perform handover to an access method that supports only packet connection in order to add a service to be used while using a service in one of the two access methods. was there.

  The present invention has been made to solve the above-described problem, and uses one of the two access methods while handing over one service with one access method and handing over to an access method corresponding to only packet connection. An object of the present invention is to provide a radio communication system, a radio communication method, and a radio base station apparatus to which a service can be added.

  In order to achieve the above object, the present invention provides a first wireless communication network that wirelessly communicates with a wireless terminal device and provides a voice call service through circuit-switched connection, wirelessly communicates with the wireless terminal device, and packet A second wireless communication network that provides a packet communication service by switched connection, and a third wireless that wirelessly communicates with a wireless terminal device and selectively provides a voice call service and a packet communication service by VoIP by packet switched connection A wireless terminal device that is provided with a voice call service through a communication network and a first wireless communication network, or a wireless terminal device that is provided with a packet communication service through a second wireless communication network is connected to a third wireless device. A handover control means for handing over to the communication network, and a wireless terminal apparatus handed over to the third wireless communication network by the handover control means The voice communication service by VoIP and the packet communication service are provided through the third wireless communication network, and service control means for providing the wireless communication apparatus with the service control means.

  As described above, in the present invention, the wireless terminal device receiving the voice call service through the first wireless communication network, or the wireless terminal device receiving the packet communication service through the second wireless communication network Is handed over to the third wireless communication network, and this wireless terminal device is provided with the voice communication service by VoIP and the packet communication service to the wireless communication device through the third wireless communication network.

  Therefore, according to the present invention, it is possible to add a service to be used by handing over to an access method corresponding to only packet connection while using one of the two access methods. A wireless communication system can be provided.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a configuration of a mobile communication system according to the present invention. A 1xRTT access network as an access method for circuit switched connection and an EVDO access network of an access method for packet switched connection are 3.9 generation access. It is connected to an EPC (Evolved Packet Core) network (E-UTRAN access network) that accommodates the E-UTRAN access method, which is a method, so that both access networks can operate in cooperation with each other.

  The 1xRTT access network is an access network compliant with, for example, 3GPP2 A.S0001-A and A.S0008-C, and is a base station 1xRTT BS101 that performs communication with the terminal UE in the 1xRTT scheme, and 1xRTT that supervises the 1xRTT access network A mobile switching center (MSC) 102 and a 1xCS IWS 103 that performs mutual message conversion between 1xRTT MSC and MME are provided. The MSC 102 is connected to a public line network called a PSTN (Public Switched Telephone Network) 104 and is connected to a voice network. Provides circuit switching services such as calls.

  The EVDO access network is an access network compliant with, for example, 3GPP2 A.S0007-A and A.S0008-C, and is connected to a base station EVDO AN (Access Node) 201 that communicates with the terminal UE by the EVDO method, and packet connection A PCF (Packet Control Function) 202 that performs control, an EVDO access network and an IP network are connected, and a PDSN (Packet Data Serving Node) 203 that is a packet data terminating device is provided, and the EVDO system is connected via the PDSN 203 Provides packet communication services to terminals.

  The E-UTRAN access network is an access network that complies with, for example, 3GPP TS 23.401 v8.2.0 and 3GPP TS23.402 v8.2.0, and communicates with the terminal UE using the E-UTRAN method, which is the 3.9th generation access method. Base station eNodeB 301 (included in E-UTRAN 300 in FIG. 1) and a core network called EPC (Evolved Packet Core) / EPS (Evolved Packet System). The EPC is connected to a mobility management entity (MME) 302 that controls mobility management, an S-GW (Serving-Gateway) 303 that connects the serving network and the roaming network, and a packet communication network outside the network as constituent elements. PDN-GW (Packet Data Network-Gateway) 304, server authentication, server HSS (Home Subscriber Server) 305 holding location management information, PCRF (Policy Charging Rule Function) 306 in charge of billing function, authentication and authorization Accounting information server 3GPP AAA (Authentication, Authorization and Accounting) Server 307, and these functions include Operator's IP Service 308 and PDN-GW 304 that provide IP (Internet Protocol) services such as IMS (IP Multimedia System). Connected through. In addition, as one of the service providers, for example, the VCC AS (Voice Call Continuity Application Server) function, which is a function compliant with 3GPP TS23.216 v8.0.0, continues voice service when the access network is switched. 309.

  In FIG. 1, a mobile communication system developed by a certain operator is described. Therefore, the components provided for so-called roaming, which make it possible to use the services provided by the mobile communication system of the operator in the mobile communication systems of other operators with which the operator is affiliated, are not specified. In the case of a mobile communication system in consideration of roaming, the constituent elements are different. For example, this can be realized by adding constituent elements necessary for roaming by a method based on 3GPP TS23.402 v8.2.0.

  The terminal UE according to the present invention can perform wireless connection with each access method supported by the mobile communication system. That is, in the case of FIG. 1, the terminal UE includes a 1xRTT wireless communication unit 10, an EVDO wireless communication unit 20, and an E-UTRAN wireless communication unit 30. Note that the terminal UE is generally called MS or AT in 1xRTT and EVDO, respectively, but in the following description, the terminal UE is collectively called the terminal UE.

  In addition, as a new function of the mobile communication system according to the present invention, a mobile management function that allows a terminal to continue a service by switching a plurality of access methods connected to an EPC, and a service connection method are converted. It has a packet switching connection-circuit switching connection conversion (Domain Transfer) function and the like.

Next, the operation of the radio communication system having the above configuration will be described.
First, referring to FIG. 2, a terminal UE receiving a voice call service by circuit switching connection through a 1xRTT access network adds a packet communication service by handover (HO) to an E-UTRAN access network, The operation when receiving two services simultaneously will be described.

(Sequence s101)
The terminal UE communicates with the base station 1xRTT BS 101 using the wireless communication unit 10 and performs a voice call through circuit-switched connection via the 1xRTT access network.

(Sequence s102)
Eventually, if the terminal UE detects that a packet communication request such as web access or content download has occurred from a user while making a voice call, the 1xRTT method that is currently making a voice call supports packet-switched connections. Therefore, it is determined that the request for packet communication cannot be accepted, and the change (handover) to the E-UTRAN access method capable of voice communication and packet communication by VoIP is determined.

(Sequence s103)
Then, based on the above determination, the terminal UE requests an Attach to the E-UTRAN 300 from the 1xRTT MSC 102 through the existing circuit switching link in order to start handover to the E-UTRAN access network. This Attach request (E-UTRAN attach request) message is transmitted to the 1xRTT MSC 102 via the 1xRTT network base station (1xRTT BS101). On the other hand, the 1xRTT MSC 102 transmits the message to the 1xCS IWS 103 as an A1 signaling Attach request. The 1xCS IWS 103 tunnels the transmitted message and sends it to the MME 302 on the E-UTRAN 300 side as an S102 Direct transfer Attach request.

(Sequence s104)
Next, when there is no UE context, which is information for the MME 302 to control the terminal UE, an authentication process is performed so that the E-UTRAN 300 authenticates the terminal UE. That is, the MME 302 inquires the UE context information to the HSS 305 and requests an authentication process from the terminal UE. And terminal UE performs the response with respect to Authentication request with respect to MME302, and sends and receives the message required for Authentication mutually.

  Note that, when executing this Authentication processing request, the terminal UE performs message exchange with the E-UTRAN 300 side through the existing circuit-switched link as in the previous Attach request. If the connected MME 302 is changed, the MME 302 performs an MME location update (Update Location) process on the HSS 305 in accordance with the authentication process.

  In addition, when it is necessary to confirm the subscriber identifier IMSI (International Mobile Subscriber Identity) of the terminal UE, the ID confirmation request (Identity Request) is sent from the network side to the terminal UE via the MME 302 prior to the above authentication process. Required. The terminal UE performs Identity confirmation by performing an appropriate response to the Identity Request.

(Sequence s105)
Subsequently, the MME 302 issues an EPS basic bearer (default bearer) connection request (Create Default Bearer request) to the S-GW 303.

(Sequence s106)
The S-GW 303 that has received the connection request issues a bearer connection request to the PDN-GW 304. Further, the S-GW 303 makes a session switching (data path switching) request to the PCRF 306 and inquires the PCRF 306 about QoS (Quality of Service) and billing information after the data path switching by the handover. The PCRF 306 responds to the PDN-GW 304 with the QoS and charging information after switching the data path, and the PDN-GW 304 that has received the response updates the QoS and charging information. By these processes, the session is switched by handover.

  The above data path switching process has been described in the case where the protocol between the S-GW 303 and the PDN-GW 304 is based on GTP (GPRS Tunneling Protocol). On the other hand, when the protocol between the S-GW 303 and the PDN-GW 304 is based on PMIP (Proxy Mobile Internet Protocol), the configuration required for the data path switching is the same although the data path switching process is different. -Data path switching is realized by exchanging necessary information between the GW 304 and the PCRF 306.

(Sequence s107)
When session switching is completed, the S-GW 303 notifies the MME 302 to that effect using Create Default bearer response. If it is determined that an additional dedicated EPS bearer (Dedicated bearer) is necessary, the dedicated bearer setting request (Create Dedicated bearer request) is also sent to the MME 302 and the S-GW 303 activates the dedicated bearer. To implement.

(Sequence s108)
The MME 302 that has received the notification returns to the terminal UE as S102 Direct transfer Attach accept that the Attach processing has been successfully performed through the 1xCS IWS 103 and the 1xRTT MSC 102. When a Create Dedicated bearer request is received in sequence s107, a bearer setup request is also sent at the same time.

(Sequence s109)
The terminal UE that has received the attach accept notifies the MME 302 of the attach process completion (E-UTRAN attach complete) via the 1xRTT access network (1xRTT MSC102 and 1xCS IWS103). When receiving a bearer setup request in sequence s108, the terminal UE performs bearer setup and returns a bearer setup response.

(Sequence s110)
The MME 302 that has received the notification of completion of the attach process notifies the S-GW 303 that the dedicated bearer has been activated as a Create Dedicated Bearer response. The EPS bearer setting is completed by the above sequences s105 to s110. In s106, when the protocol between the S-GW 303 and the PDN-GW 304 is based on PMIP (Proxy Mobile Internet Protocol), s110 is not performed.

(Sequence s111)
On the other hand, the terminal UE that has sent the attach processing completion message in sequence s109 activates the wireless communication unit 30 and synchronizes with the base station eNodeB 301.

(Sequence s112)
Then, the terminal UE sends a connection request (Service Request) and a service request (Service Request) to the E-UTRAN 300 side through the base station eNodeB 301. The eNodeB 301 that receives this request is connected to the MME 302, and the MME 302 Is connected to the S-GW 303, and the S-GW 303 is connected to the PDN-GW 304, so that the terminal UE establishes a communication link for performing the communication after the handover on the E-UTRAN 300 side.

  In this service request, both the voice call service by VoIP, which replaces the voice call service by circuit-switched connection that has been implemented through the 1xRTT access network, and the packet communication service that cannot be connected by the 1xRTT access network from the sequence s101. Is included. For this reason, both the voice call service and the packet communication service are provided between the E-UTRAN 300 side including the terminal UE and the eNodeB 301 and the MME 302, S-GW 303, and PDN-GW 304 connected thereto by the sequence s112. To establish a communication link.

(Sequence s113)
When a communication link for providing two services is established between the E-UTRAN 300 side including the terminal UE and the eNodeB 301 and the MME 302, S-GW 303, and PDN-GW 304 connected to the E-UTRAN 300 side, the handover completion is set to 1xRTT of the handover source. In order to notify the access network, the MME 302 transmits a handover completion message to the 1xRTT MSC 102 via the 1xCS IWS 103. In response to this, the 1xRTT MSC 102 informs the 1xRTT BS 101 of the completion of the handover, and performs a handover completion process (resource release) in cooperation with the 1xRTT MSC 102 and the 1xRTT BS 101.

(Sequence s114)
Then, the E-UTRAN access network provides a voice call service and a packet communication service to the terminal UE by simultaneous connection. That is, voice packets and data packets transmitted from the terminal UE are transmitted from the PDN-GW 304 to the packet communication network through the base stations eNodeB 301 and MME 302, and conversely, addressed to the terminal UE given to the PDN-GW 304 from the packet communication network. Are transmitted to the terminal UE through the MME 302 and the base station eNodeB 301.

  Next, referring to FIG. 3, a terminal UE receiving a packet communication service by packet switching connection through the EVDO access network adds a voice call service by handing over to the E-UTRAN access network. The operation when receiving one service is described.

(Sequence s201)
The terminal UE communicates with the base station EVDO AN 201 using the radio communication unit 20, and performs a packet call by packet switching connection via the EVDO access network.

(Sequence s202)
Eventually, when the terminal UE detects a request for voice communication from the user while performing a packet call, for example, the EVDO system currently performing the packet call does not support circuit switched connection. It is determined that the request cannot be accepted, and a change (handover) to the E-UTRAN access method capable of voice communication and packet communication by VoIP is determined.

(Sequence s203)
Then, based on the determination, the terminal UE requests an attach to the E-UTRAN 300 from the base station EVDO AN 201 through the existing packet switching link in order to start handover to the E-UTRAN access network. The message of this Attach request (E-UTRAN attach request) is tunneled through the base station EVDO AN 201 and transferred to the MME 302 on the E-UTRAN 300 side as an S101 Direct transfer Attach request.

(Sequence s204)
Next, when there is no UE context, which is information for the MME 302 to control the terminal UE, an authentication process is performed so that the E-UTRAN 300 authenticates the terminal UE. That is, the MME 302 inquires the UE context information to the HSS 305 and requests an authentication process from the terminal UE. And terminal UE implements the response with respect to Authentication request with respect to MME302, and sends and receives the message required for Authentication mutually.

  When executing this Authentication processing request, the terminal UE performs message exchange with the E-UTRAN 300 side through an existing packet exchange link, as in the previous Attach request. When the connected MME 302 is changed, the MME 302 performs an MME location update (Update Location) process on the HSS 305 in accordance with the authentication process.

  In addition, when it is necessary to confirm the subscriber identifier IMSI (International Mobile Subscriber Identity) of the terminal UE, the ID confirmation request (Identity Request) is sent from the network side to the terminal UE via the MME 302 prior to the above authentication process. Required. The terminal UE performs Identity confirmation by performing an appropriate response to the Identity Request.

(Sequence s205)
Subsequently, the MME 302 issues an EPS basic bearer (default bearer) connection request (Create Default Bearer request) to the S-GW 303.

(Sequence s206)
The S-GW 303 that has received the connection request issues a bearer connection request to the PDN-GW 304. Further, the S-GW 303 makes a session switching (data path switching) request to the PCRF 306 and inquires the PCRF 306 about QoS (Quality of Service) and billing information after the data path switching by the handover. The PCRF 306 responds to the PDN-GW 304 with the QoS and charging information after switching the data path, and the PDN-GW 304 that has received this updates the QoS and the charging information. By these processes, the session is switched by handover.

  The above data path switching process has been described in the case where the protocol between the S-GW 303 and the PDN-GW 304 is based on GTP (GPRS Tunneling Protocol). On the other hand, when the protocol between the S-GW 303 and the PDN-GW 304 is based on PMIP (Proxy Mobile Internet Protocol), the configuration required for the data path switching is the same although the data path switching process is different. -Data path switching is realized by exchanging necessary information between the GW 304 and the PCRF 306.

(Sequence s207)
When session switching is completed, the S-GW 303 notifies the MME 302 to that effect using Create Default bearer response. If it is determined that an additional dedicated EPS bearer (Dedicated bearer) is necessary, the dedicated bearer setting request (Create Dedicated bearer request) is also sent to the MME 302 and the S-GW 303 activates the dedicated bearer. To implement.

(Sequence s208)
Receiving the notification, the MME 302 returns to the terminal UE through the base station EVDO AN 201 as S101 Direct transfer Attach accept that the Attach process has been successfully performed. When a Create Dedicated bearer request is received in sequence s207, a bearer setup request is also sent at the same time.

(Sequence s209)
The terminal UE that has received the attach accept notifies the MME 302 of the attach process completion (E-UTRAN attach complete) via the EVDO AN 201 of the EVDO access network. When receiving a bearer setup request in sequence s208, the terminal UE performs bearer setup and returns a bearer setup response.

(Sequence s210)
The MME 302 that has received the notification of completion of the attach process notifies the S-GW 303 that the dedicated bearer has been activated as a Create Dedicated Bearer response. The EPS bearer setting is completed by the above sequences s205 to s210. In s206, when the protocol between the S-GW 303 and the PDN-GW 304 is based on PMIP (Proxy Mobile Internet Protocol), s210 is not performed.

(Sequence s211)
On the other hand, the terminal UE that has sent the attach processing completion message in sequence s209 activates the wireless communication unit 30 and synchronizes with the base station eNodeB301.

(Sequence s212)
Then, the terminal UE sends a connection request (Service Request) and a service request (Service Request) to the E-UTRAN 300 side through the base station eNodeB 301. The eNodeB 301 that receives this request is connected to the MME 302, and the MME 302 Is connected to S-GW303. By connecting the S-GW 303 and the PDN-GW 304, the terminal UE establishes a radio link for performing communication after handover on the E-UTRAN 300 side. E-UTRAN300.

  It should be noted that this service request includes both a packet and a communication service instead of the packet communication service by the packet switching connection performed through the base station EVDO AN201 from the sequence s201, and a voice call service by VoIP. Therefore, both the voice call service and the packet communication service are provided between the E-UTRAN 300 side including the terminal UE and the eNodeB 301 and the MME 302, S-GW 303, and PDN-GW 304 connected thereto by the sequence s212. To establish a communication link.

(Sequence s213)
When a communication link for providing two services is established between the E-UTRAN 300 side including the terminal UE and the eNodeB 301 and the MME 302, S-GW 303, and PDN-GW 304 connected to the E-UTRAN 300 side, In order to notify the access network, the MME 302 transmits a handover completion message to the EVDO AN 201. In response, EVDO AN 201 performs a handover completion process. EVDO AN 201 then releases network resources on the EVDO side in cooperation with PCF 202 and PDSN 203.

(Sequence s214)
Then, the E-UTRAN access network provides a voice call service and a packet communication service to the terminal UE by simultaneous connection. That is, voice packets and data packets transmitted from the terminal UE are transmitted from the PDN-GW 304 to the packet communication network through the base stations eNodeB 301 and MME 302, and conversely, addressed to the terminal UE given to the PDN-GW 304 from the packet communication network. Are transmitted to the terminal UE through the MME 302 and the base station eNodeB 301.

  Next, with reference to FIG. 4, the operation when the packet communication service is terminated from the state where the voice call service and the packet communication service are simultaneously performed by the processing shown in FIG. 2 or FIG. 3 will be described.

(Sequence s401)
Through the processing shown in FIG. 2 or FIG. 3, the terminal UE is simultaneously provided with the voice call service and the packet communication service through the E-UTRAN network.

(Sequence s402)
Eventually, when receiving a request to end the packet communication service from the user, for example, the terminal UE disconnects the packet communication link used in the packet communication service with the base station eNodeB 301 according to a predetermined procedure. In accordance with this operation, eNodeB 301, MME 302, S-GW 303, PDN-GW 304, and PCRF 306 cooperate to perform bearer resource switching on the network side. That is, the eNodeB 301 transmits the packet communication service end to the MME 302.

  Next, since the packet communication service has been terminated, the MME 302 makes a bearer change request (packet service bearer release request) to set only the VoIP bearer. The S-GW 303 transmits the bearer change request received from the MME 302 to the PDN-GW 304, and further, the PDN-GW 304 requests the PCRF 306 to change the session when the Packet service bearer is released. When each network element responds to these requests, the packet communication link is disconnected, and the terminal UE continues the VoIP service through the E-UTRAN network.

  In addition, although the example which triggered by the request | requirement from a user was given here, you may cut | disconnect similarly in response to a request | requirement other than a user. Further, the communication link with the terminal UE may be disconnected from the E-UTRAN access network.

(Sequence s403)
The base station eNodeB 301 that has disconnected the packet communication link with the terminal UE determines to hand over the ongoing voice call service to the 1xRTT access network. Note that it is also possible to decide to hand over to the 1xRTT access network again only when voice communication is performed by circuit switching connection through the 1xRTT access network before handing over to the E-UTRAN access network.

(Sequence s404)
The E-UTRAN access network including the terminal UE and the base station eNodeB 301 hands over the voice call service from the E-UTRAN network to the 1xRTT access network in accordance with the provisions of 3GPP TS23.216.

(Sequence s405)
The terminal UE communicates with the base station 1xRTT BS 101 using the radio communication unit 10 and performs a voice call through circuit-switched connection via the 1xRTT access network.
As described above, the terminal UE is handed over from the E-UTRAN network to the 1xRTT access network with the end of the packet communication service, and receives the voice call service through the 1xRTT access network.

  Next, with reference to FIG. 5, the operation when the voice call service is terminated from the state where the voice call service and the packet communication service are simultaneously performed by the processing shown in FIG. 2 or FIG. 3 will be described.

(Sequence s501)
Through the processing shown in FIG. 2 or FIG. 3, the terminal UE is simultaneously provided with the voice call service and the packet communication service through the E-UTRAN network.

(Sequence s502)
Eventually, when the terminal UE receives a request to end the voice call service from the user, for example, the terminal UE disconnects the packet communication link (VoIP link) used in the voice call service with the base station eNodeB 301 according to a predetermined procedure. To do. In accordance with this operation, eNodeB 301, MME 302, S-GW 303, PDN-GW 304, and PCRF 306 cooperate to perform bearer resource switching on the network side. That is, the eNodeB 301 transmits the VoIP end to the MME 302.

  Next, since VoIP has been terminated, the MME 302 makes a bearer change request (VoIP bearer release request) so as to set only the packet communication bearer. The S-GW 303 transmits the bearer change request received from the MME 302 to the PDN-GW 304, and the PDN-GW 304 requests the PCRF 306 to change the session accompanying the VoIP bearer release. When each network element responds to these requests, the VoIP link is disconnected, and the terminal UE continues the packet communication service through the E-UTRAN network.

  In addition, although the example which triggered by the request | requirement from a user was given here, you may cut | disconnect similarly in response to a request | requirement other than a user. Further, the communication link with the terminal UE may be disconnected from the E-UTRAN access network.

(Sequence s503)
The base station eNodeB 301 that has disconnected the VoIP link with the terminal UE determines to hand over the ongoing packet communication service to the EVDO access network. Note that it may be determined that the handover to the EVDO access network is performed again only when packet communication is performed by packet switching connection through the EVDO access network before the handover to the E-UTRAN access network.

(Sequence s504)
The E-UTRAN access network including the terminal UE and the base station eNodeB 301 hands over the packet communication service from the E-UTRAN network to the EVDO access network in accordance with the provisions of 3GPP TS34.402.

(Sequence s505)
The terminal UE communicates with the base station EVDO AN 201 using the wireless communication unit 20, and performs packet communication by packet switching connection via the EVDO access network.
As described above, the terminal UE is handed over from the E-UTRAN network to the EVDO access network with the termination of the voice call service, and receives the packet communication service through the EVDO access network.

  Note that, in the sequence s403 in FIG. 4 and the sequence s503 in FIG. 5, the determination criterion for determining the execution of the handover is not only the determination criterion based on the type of the access network connected before the handover to the E-UTRAN access network. There are several possible. For example, it may be determined based on the current traffic status of the E-UTRAN access network.

  In this case, the base station eNodeB 301 measures the traffic state, and when the load exceeds a preset threshold value and determines that the E-UTRAN access network is handed over to another access network, If the value is below the threshold value, the communication through the E-UTRAN access network is continued without performing the handover.

  Next, referring to FIG. 6, in the state where the voice call service and the packet communication service are simultaneously performed by the process shown in FIG. 2 or 3, handover is performed to the EVDO access network according to the communication environment of the terminal UE. The operation when doing this will be described. In this case, it is assumed that the voice call service and the packet communication service are simultaneously provided through the EVDO access network.

(Sequence s601)
Through the processing shown in FIG. 2 or FIG. 3, the terminal UE is simultaneously provided with the voice call service and the packet communication service through the E-UTRAN network.

(Sequence s602)
The base station eNodeB 301 is a terminal immediately after two services are started, when a predetermined time elapses after the two services are started, or when transmission power for the terminal UE exceeds a preset threshold. It decides to request the UE to measure the communication environment (communication quality).

(Sequence s603)
The base station eNodeB 301 requests the terminal UE to measure the communication environment. Here, the eNodeB 301 is an access network (for example, EVDO access network) that can simultaneously perform a voice call service and a packet communication service, which is currently implemented in the E-UTRAN network via the eNodeB 301, for the terminal UE. Can be designated as a measurement target.
(Sequence s604)
On the other hand, the terminal UE receives a pilot signal from another access network (for example, EVDO access network) and measures the quality of communication that can be performed through the other access network.
(Sequence s605)
Then, the terminal UE notifies the base station eNodeB 301 of the communication quality measured in sequence s604.

(Sequence s606)
On the other hand, the base station eNodeB 301 determines whether or not the communication quality notified from the terminal UE exceeds a preset threshold value. As a result, when the communication quality exceeds a preset threshold, it is determined to hand over the terminal UE to another access network (for example, EVDO access network). In the following description, a case where handover is performed to the EVDO access network will be described as an example.

(Sequence s607)
The UE and the E-UTRAN access network including the base station eNodeB 301 hand over the voice call service and the packet communication service from the E-UTRAN network to the EVDO access network in accordance with the provisions of 3GPP TS34.402.

(Sequence s608)
The terminal UE communicates with the base station EVDO AN 201 using the radio communication unit 20, and performs voice communication and packet communication by VoIP by packet switching connection via the EVDO access network.
As described above, the terminal UE is handed over from the E-UTRAN network to the EVDO access network with good communication quality, and two communication services are continued through the EVDO access network.

Note that in sequence s606 in FIG. 6, not only a criterion based on communication quality but also some criteria for determining whether to perform handover can be considered. For example, it may be determined based on the current traffic status of the E-UTRAN access network.
In this case, the base station eNodeB 301 measures the traffic state, and when the load exceeds a preset threshold value and determines that the E-UTRAN access network is handed over to another access network, If the value is below the threshold value, the communication through the E-UTRAN access network is continued without performing the handover.

  As described above, in the radio communication system having the above-described configuration, as shown in FIG. 2 or FIG. 3, one of the voice communication service through the 1xRTT access network and the packet communication service through the EVDO access network is being provided. In addition, a handover to the E-UTRAN access network is provided to provide a packet communication service or a voice call service, and both the voice call service and the packet communication service are provided to the terminal UE.

  Therefore, according to the wireless communication system configured as described above, while one service is being used in one of the two access methods, a service to be used is added by handing over to an access method that supports only packet connection. can do.

  In the radio communication system having the above configuration, as shown in FIG. 4 or FIG. 5, when two services are provided to the terminal UE through the E-UTRAN access network, when one service ends, the remaining one Handover is made to an access network that can provide the service. For this reason, the load on the E-UTRAN network can be distributed and the throughput of the entire system can be increased.

  In the radio communication system having the above configuration, as shown in FIG. 6, when two services are provided to the terminal UE through the E-UTRAN access network, the terminal UE is caused to measure the communication quality of the EVDO access network. In response to this measurement result, the EVDO access network is handed over to continue the voice call service and the packet communication service. For this reason, the load on the E-UTRAN network can be distributed and the throughput of the entire system can be increased.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. Further, for example, a configuration in which some components are deleted from all the components shown in the embodiment is also conceivable. Furthermore, you may combine suitably the component described in different embodiment.

The figure which shows the structure of one Embodiment of the radio | wireless communications system concerning this invention. FIG. 3 is a sequence diagram for explaining a handover operation of the wireless communication system shown in FIG. 1. FIG. 3 is a sequence diagram for explaining a handover operation of the wireless communication system shown in FIG. 1. FIG. 3 is a sequence diagram for explaining a handover operation of the wireless communication system shown in FIG. 1. FIG. 3 is a sequence diagram for explaining a handover operation of the wireless communication system shown in FIG. 1. FIG. 3 is a sequence diagram for explaining a handover operation of the wireless communication system shown in FIG. 1.

Explanation of symbols

  UE ... terminal, 10 ... wireless communication unit, 20 ... wireless communication unit, 30 ... wireless communication unit, 101 ... base station 1xRTT BS, 102 ... 1xRTT MSC, 103 ... 1xCS IWS, 104 ... PSTN, 201 ... base station EVDO AN, 202 ... PCF, 203 ... PDSN, 300 ... E-UTRAN, 301 ... Base station eNodeB, 302 ... MME, 303 ... S-GW, 304 ... PDN-GW, 305 ... HSS, 306 ... PCRF, 307 ... 3GPP AAA Server, 308 ... Operator's IP Service, 309 ... VCC AS.

Claims (14)

A first wireless communication network that wirelessly communicates with a wireless terminal device and provides a voice call service by circuit switching connection;
A second wireless communication network that wirelessly communicates with the wireless terminal device and provides a packet communication service through a packet switched connection;
A third wireless communication network that wirelessly communicates with the wireless terminal device and selectively provides a voice call service and a packet communication service by VoIP by packet switching connection;
A wireless terminal device receiving a voice call service through the first wireless communication network or a wireless terminal device receiving a packet communication service through the second wireless communication network; Handover control means for handing over to the network;
Service control means for providing a voice communication service and packet communication service by VoIP to the wireless communication apparatus through the third wireless communication network to the wireless terminal apparatus handed over to the third wireless communication network by the handover control means; A wireless communication system comprising:   The wireless communication system according to claim 1, wherein the first wireless communication network uses a cdma2000 1x RTT method as a wireless access method for wireless communication with the wireless terminal device.   The wireless communication system according to claim 1, wherein the second wireless communication network uses a cdma2000 1x EVDO method as a wireless access method for wireless communication with the wireless terminal device.   The wireless communication system according to claim 1, wherein the third wireless communication network uses an E-UTRAN method as a wireless access method for wireless communication with the wireless terminal device. Further, when the provision of the packet communication service to the wireless communication device receiving the voice call service and the packet communication service through the third wireless communication network is terminated, the wireless communication device is changed to the first wireless communication device. First handover control means for handing over to a communication network;
The wireless terminal device handed over to the first wireless communication network by the first handover control means includes first service control means for providing a voice call service through the first wireless communication network. The wireless communication system according to claim 1.   The first handover control unit terminates the provision of the packet communication service to the wireless communication device receiving the voice call service and the packet communication service through the third wireless communication network, and the wireless communication device 6. The wireless communication device according to claim 5, wherein when the first wireless communication network is handed over to the third wireless communication network, the wireless communication device is handed over to the first wireless communication network. Wireless communication system. Further, when the provision of the voice call service to the wireless communication apparatus receiving the voice call service and the packet communication service through the third wireless communication network is terminated, the wireless communication apparatus is changed to the second wireless communication apparatus. Second handover control means for handing over to a communication network;
The wireless terminal apparatus handed over to the second wireless communication network by the second handover control means includes second service control means for providing a packet communication service through the second wireless communication network. The wireless communication system according to claim 1.   The second handover control means terminates the provision of the voice call service to the radio communication apparatus receiving the voice call service and the packet communication service through the third radio communication network, and the radio communication apparatus 8. The wireless communication device according to claim 7, wherein when the second wireless communication network is handed over to the third wireless communication network, the wireless communication device is handed over to the second wireless communication network. Wireless communication system. A measuring means for measuring communication quality between the wireless terminal device and the second wireless communication network;
A third handover control means for handing over the wireless communication apparatus to the second wireless communication network when the communication quality measured by the measuring means is equal to or higher than a preset threshold;
A third service control means for providing a voice call service and a packet communication service by VoIP to the wireless terminal apparatus handed over to the second wireless communication network by the third handover control means, via the second wireless communication network; The wireless communication system according to claim 1, further comprising: And measuring means for measuring traffic of the third wireless communication network;
A fourth handover control means for handing over the wireless communication device to the second wireless communication network when the traffic measured by the measuring means is greater than or equal to a preset threshold;
A fourth service control means for providing a voice call service and a packet communication service by VoIP to the wireless terminal apparatus handed over to the second wireless communication network by the fourth handover control means, via the second wireless communication network; The wireless communication system according to claim 1, further comprising: A first wireless communication network that wirelessly communicates with a wireless terminal device and provides a voice call service by circuit-switched connection; and a second wireless communication network that wirelessly communicates with the wireless terminal device and provides a packet communication service by packet-switched connection Wireless communication in a wireless communication system comprising: a wireless communication network; and a third wireless communication network that wirelessly communicates with the wireless terminal device and selectively provides VoIP voice call service and packet communication service by packet switching connection A method,
A wireless terminal device receiving a voice call service through the first wireless communication network or a wireless terminal device receiving a packet communication service through the second wireless communication network; A handover control step for handover to the network;
A service control step of providing a voice communication service and a packet communication service by VoIP to the wireless communication device through the third wireless communication network to the wireless terminal device handed over to the third wireless communication network by the handover control step; A wireless communication method comprising: A wireless base station device used in a wireless communication network that wirelessly communicates with a wireless terminal device and selectively provides a voice call service and a packet communication service by VoIP by packet switching connection,
Packet communication through a wireless terminal device that provides a voice call service through a first wireless communication network that provides a voice call service through circuit-switched connection, or a second wireless communication network that provides a packet communication service through a packet-switched connection Handover control means for handing over a wireless terminal device receiving service to the wireless communication network;
The wireless terminal apparatus handed over to the wireless communication network by the handover control means includes service control means for providing a voice communication service and packet communication service by VoIP to the wireless communication apparatus through the wireless communication network. A wireless base station device. A first wireless communication network that wirelessly communicates with a wireless terminal device and provides a voice call service by circuit switching connection;
A second wireless communication network that wirelessly communicates with the wireless terminal device and provides a packet communication service through a packet switched connection;
A third wireless communication network that wirelessly communicates with the wireless terminal device and selectively provides a voice call service and a packet communication service by VoIP by packet switching connection;
When the first wireless communication network receives an E-UTRAN attach request from a wireless terminal device that is provided with a voice call service through the first wireless communication network, or packet communication is performed through the second wireless communication network. Handover control means for handing over to the third wireless communication network when the second wireless communication network receives an E-UTRAN attach request from a wireless terminal device receiving service;
The first wireless communication network transmits an E-UTRAN attach accept to the wireless terminal device handed over to the third wireless communication network by the handover control means, and the voice call by VoIP is transmitted through the third wireless communication network. A wireless communication system comprising service control means for providing a service and a packet communication service to the wireless communication device. A first wireless communication network that wirelessly communicates with a wireless terminal device and provides a voice call service by circuit switching connection;
A second wireless communication network that wirelessly communicates with the wireless terminal device and provides a packet communication service through a packet switched connection;
A third wireless communication network that wirelessly communicates with the wireless terminal device and selectively provides a voice call service and a packet communication service by VoIP by packet switching connection;
A wireless terminal device receiving a voice call service through the first wireless communication network or a wireless terminal device receiving a packet communication service through the second wireless communication network; Handover control means for handing over to the network;
Service control means for providing a voice communication service and packet communication service by VoIP to the wireless communication apparatus through the third wireless communication network to the wireless terminal apparatus handed over to the third wireless communication network by the handover control means; Comprising
The third wireless communication network includes first control means and second control means,
When the first control unit receives a handover request from the first wireless communication network, the first control unit transmits a Create Default Bearer request to the second control unit,
When the second control means receives the Create Default Bearer request, it sets a bearer for voice call and a bearer for packet communication, and transmits Create Default Bearer Response to the first control means. A wireless communication system.

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