JP2010187261A - Communication system and handover method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication system and handover method, for performing a smooth handover between different communication systems such as the handover from a 3GPP (Third Generation Partnership Project) communication system to the IEEE802.16e communication system or the like. <P>SOLUTION: In the communication system, during execution of communication via a 3G network 200, a UE 100 notifies an IEEE802.16e network 300 side of communication control information for handover processing via a virtual directly connected communication path established between the UE 100 and an AGN-GW 302 by tunneling processing. Then, a BS 301 can execute communication processing with respect to the handover processing from the UE 100 using the communication control information notified beforehand. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a communication system capable of executing different communication methods and a handover method therebetween.

  In recent years, both communication systems specified by 3GPP (Third Generation Partnership Project) (for example, communication systems using W-CDMA and OFDMA / SC-FDMA) and communication systems specified by IEEE 802.16e (for example, OFDMA) Mobile devices equipped with are considered. This mobile device can automatically switch to the IEEE 802.16e communication system when moving from the communication area of the 3GPP communication system to the communication area of the IEEE 802.16e communication system. Similarly, it is possible to switch from the IEEE 802.16e communication system to the 3GPP communication system, and to perform communication suitable for the communication area.

  If the communication method is different, the communication area may be different depending on the feature of the method and the strategy of the service provider. For example, the 3GPP communication system area is provided in a wide area, whereas the IEEE 802.16e communication system area overlaps with the 3GPP communication system area, but only a part of the area may be provided. It is done. In this case, when a mobile station in the communication area of the 3GPP communication system moves to an area where communication is possible even in the IEEE 802.16e communication system, communication suitable for the preference of the user and the service provider is performed by performing a handover process. Can be realized. For example, when there is a difference in charge and communication speed between methods, in an area where communication is possible with both communication methods, handover can be performed to an appropriate network according to user preferences, and communication can be continued.

  For example, FIG. 1 shows a handover process sequence defined in IEEE 802.16e. As shown in FIG. 1, a request signal, a response signal, etc. for handover processing are transmitted and received between the UE 100 and the 3GPP network 200 (S01). After that process, the handover process (S03) and the exchange of function information, authentication information, etc. of the UE 100, which are communication control information necessary for the handover, are performed with the IEEE 802.16e network 300 (S04). In performing the handover process in this way, the processes of S03 and S04 are executed, so that it takes time to complete the handover process and it is difficult to perform a smooth handover.

  Therefore, in order to perform a smooth handover, in 3GPP TR36.938, when performing a handover from 3GPP to IEEE 802.16e, it is considered that the process of S04 described above is omitted, for example, as shown in FIG. A sequence diagram is proposed. In FIG. 2, an instruction signal (RRCCONNECETION RECONFIGURATION) for connecting from the 3GPP network 200 to the IEEE 802.16e network 300 is output during communication processing via the 3GPP network (S11) (S12). Upon receiving this, the UE 100 determines to perform communication control information pre-registration processing (S13), and performs authentication processing and pre-registration processing (S14).

  Similarly, FIG. 3 shows a sequence diagram in the action phase at the time of handover defined in 3GPP. As shown in FIG. 3, when user data is being transmitted / received (S21), a measurement process for the IEEE 802.16e communication method is started (S22). Then, an instruction signal for that purpose is transmitted using RRC CONNECTIONRECONFIGURATION (S23), and the UE receiving this performs measurement processing (S24). When the measurement result is transmitted from the UE (S25), according to the measurement result, in the 3GPP network, it is determined to perform the handover process to the IEEE 802.16e communication area (S26). Information pre-registration processing is performed for handover processing (S27), and then handover processing is executed (S28-S30).

  These handover processes are defined in 3GPP TR36.99 (Non-Patent Document 1).

3GPP TR36.9938

  However, in the technique described in Non-Patent Document 1 described above, it is not stipulated to be feasible when performing handover, and as a result, smooth communication cannot be executed. That is, since the communication procedure for transmitting information from the 3GPP communication area to the IEEE 802.16e communication area and the transmission format of the control signal are different, the communication procedure using the 3GPP communication method performs registration processing for the IEEE 802.16e network. As a result, it is difficult to execute a smooth handover.

  Therefore, an object of the present invention is to provide a communication system and a handover method capable of smoothly performing a handover between different communication methods such as a 3GPP communication method to an IEEE 802.16e communication method.

  In order to solve the above-mentioned problems, a communication system of the present invention is arranged in a first base station arranged in one communication network of one communication method and in another communication network of another communication method. In the communication system comprising the second base station and the mobile device, the mobile device includes a first communication means for executing a communication method via the first base station, and the second base station. A second communication unit that executes another communication method via a station, and the mobile device through a tunneling process prior to a handover process to the second base station during communication by the first communication unit. A notification means for notifying the other communication network side of communication control information required for communication connection processing via a virtual direct connection communication path established between the communication network and the other communication network, and the notification means notification And a handover means for starting a handover process from the first base station to the second base station by omitting a communication control information notification process, wherein the second base station includes the mobile device. Communication means for executing communication processing with the mobile device using the communication control information notified by the notification means when the handover processing by the handover means is completed.

  According to the present invention, for performing the handover process via the virtual direct connection communication path established between the mobile station and the second base station by the tunneling process during the communication by the first communication method. Communication control information is transmitted to the other communication network side, and then the handover process is executed using the communication control information notified in advance, and the second base station performs the communication process for the handover process from the mobile station. Can be executed. Accordingly, smooth communication control information notification between different communication methods can be performed before the handover process. Therefore, smooth handover processing can be executed without exchanging communication control information during the handover processing.

  Further, the communication system of the present invention further includes a handover control device that connects the first base station and the second base station, and the notification means communicates with the handover control device via the direct communication path. Between each of the plurality of communication control information by sequentially transmitting and receiving a request signal and a response signal corresponding to each of the plurality of communication control information, to notify the handover control device of all of the plurality of communication control information, the handover control device, It is preferable that communication control information is extracted from a control signal defined by another communication method, and the extracted communication control information is notified to the other communication network side via the direct connection communication path.

  According to the present invention, all of the plurality of pieces of communication control information are obtained by sequentially transmitting / receiving request signals and response signals corresponding to each of the plurality of pieces of communication control information to / from the handover control apparatus via the direct connection communication path. To the handover control apparatus, and the handover control apparatus extracts communication control information from a control signal defined by another communication method, and transmits the extracted communication control information to another communication via a direct communication path. Can be notified to the network side. Accordingly, smooth communication control information notification between different communication methods can be performed before the handover process.

  In the communication system of the present invention, it is preferable that the notification means notifies communication control information using a call control signal plane. According to the present invention, the communication control information notification process can be reliably executed.

  In the communication system of the present invention, it is preferable that the notification means notifies communication control information using a user information transfer plane. According to this invention, communication control information notification processing can be realized by simple processing.

  In addition, the communication system of the present invention further includes a handover control device that connects the first base station and the second base station, and the notification means communicates with the handover control device via the communication path. By sequentially transmitting one request signal including a plurality of communication control information, receiving the response signal, and transmitting a confirmation signal for confirming the response signal. The handover control apparatus notifies the handover control apparatus, the handover control apparatus transmits a response signal to the request signal transmitted from the notification means, extracts communication control information from the request signal, and extracts the extracted communication control information. Is preferably transmitted to the other network side.

  According to the present invention, transmission of one request signal including communication control information, reception of the response signal, and confirmation signal for confirming the response signal with the handover control apparatus via the communication path. By sequentially executing the transmission, the communication control information is notified to the handover control apparatus, and the handover control apparatus transmits a response signal to the request signal and extracts the communication control information from the request signal. Communication control information can be transmitted to the other network side. Thereby, smooth notification of communication control information between different communication methods can be performed before the handover process. Furthermore, by including all of the plurality of communication control information in one request signal, the sequence processing can be reduced. For example, in the control procedure defined in IEEE802.16e, 5.5 round-trip sequence processing is required. However, in the present invention, only request, response, and confirmation processing is performed. The number of round trips is 5, and the sequence processing can be greatly reduced.

  In the communication system of the present invention, it is preferable that the notification means notifies communication control information using a call control signal plane. According to the present invention, the communication control information notification process can be quickly executed.

  In the communication system of the present invention, it is preferable that the notification means notifies communication control information using a user information transfer plane. According to this invention, communication control information notification processing can be realized by simple processing.

  By the way, the present invention can be described as the invention of the communication method as described above, and can also be described as the invention of the handover method as follows. These are substantially the same inventions only in different categories, and exhibit the same actions and effects.

  That is, the handover method of the present invention includes a first base station arranged in one communication network of one communication method, and a second base station arranged in another communication network of another communication method. In the handover method using a mobile station, the mobile station and the other communication network are subjected to a tunneling process prior to the handover process to the second base station during communication with the first base station. A notification step for notifying the other communication network side of communication control information necessary for communication connection processing via a virtual direct communication path established between the communication control and communication control after the notification processing by the notification step. A handover step of starting a handover process from the first base station to the second base station by omitting an information notification process; Wherein the handover processing in the handover step is completed that includes a communication step of performing a communication process to the handover process from the mobile station using the communication control information notified by the notification step.

  ADVANTAGE OF THE INVENTION According to this invention, the notification of the smooth communication control information between different communication systems can be performed before a handover process. Therefore, smooth handover processing can be executed without exchanging communication control information during the handover processing.

FIG. 3 is a sequence diagram of a handover process defined by IEEE 802.16e. It is a sequence diagram of a handover process defined in 3GPP. FIG. 3 is a sequence diagram in an action phase at the time of handover defined in 3GPP. It is a system configuration figure of the communications system in this embodiment. It is a block diagram which shows the function of UE100 used for the communication system of this embodiment. It is a hardware block diagram of UE100. 3 is a block diagram showing functions of an eNB 201. FIG. It is a schematic diagram which shows the direct communication path established by the tunneling process. It is a schematic diagram of the transmission format prescribed | regulated by RRC INFORMATION TRANSFER. It is a schematic diagram of the transmission format prescribed | regulated by S1AP NAS TRANSPORT. It is a schematic diagram of the transmission format prescribed | regulated by L2 Tunnel. It is a schematic diagram of the transmission format prescribed | regulated by GRE Tunnel. It is a sequence diagram of the handover process in the communication system of the present embodiment. It is a sequence diagram of the hand-over process of the communication system in a modification. It is a schematic diagram which shows the communication path | route established by the tunneling process at the time of using U-Plane. The sequence diagram of the hand-over process of the communication system in a modification is shown. The sequence diagram of the hand-over process of the communication system in a modification is shown.

  Embodiments of the present invention will be described with reference to the accompanying drawings. Where possible, the same parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 4 is a system configuration diagram of the communication system in the present embodiment. This communication system includes a UE (User Equipment) 100, a 3GPP network 200, a FAF (Forward Attachment Function) 400, and an IEEE 802.16e network 300. The UE 100 can be connected for communication. Here, the 3GPP network 200 includes an eNB (Evolved Node B: first base station) 201, an MME (Mobility Management Entity) 202, a Serving GW (Gateway) 203, and a PDN GW (Packet Data Network Gateway) 204. ing. The IEEE 802.16e network 300 includes a BS (Base Station: second base station) 301, an ASN-GW (Access Service Network Gateway), and an HA (Home Agent) 303.

  In the communication system configured as described above, the UE 100 is a mobile terminal such as a mobile phone, and can communicate with another communication network 500 via the 3GPP network 200. Then, when the UE 100 moves between the networks, the UE 100 can perform a handover process with respect to the IEEE 802.16e network 300 and can be connected to another communication network 500 via the IEEE 802.16e network 300.

  Here, the eNB 201 is a 3GPP access base station, and can establish a wireless communication connection with the UE 100 according to the 3GPP communication procedure.

  The MME 202 is a management device that performs mobility control on the UE 100. The MME 202 can further be connected to the FAF 400 for communication. The MME 202 is a device for transmitting and receiving control signals on the C-Plane.

  Serving GW 203 is a gateway device that relays user data on the U-Plane between 3GPP access and other access networks.

  The PDN GW 204 is a gateway device that relays user data on the U-Plane between the other communication network 500 and the 3GPP network 200. In FIG. 4, there is one 3GPP network 200, but there are a plurality of PGPGWs 204.

  The BS 301 is an IEEE 802.16e base station, and is a part that performs wireless communication connection with the UE 100 according to the IEEE 802.16e communication procedure.

  The ASN-GW 302 is a device that centrally controls the BS 301, which is an IEEE 802.16e base station, and can be connected to the FAF 400.

  The HA 303 is a device that performs mobility control of the IEEE 802.16e network 300. The UE 100 can be connected to another communication network 500 via the HA 303.

  In the communication system configured as described above, the UE 100 communicates with another communication network 500 via the Serving GW 203 and the PDN GW 204 while wirelessly connecting to the eNB 201. When the UE 100 moves and hands over to the IEEE 802.16e network 300, the UE 100 communicates with the IEEE 802.16e network 300 via the BS 301 and communicates with the other communication network 500 via the ASN-GW 302 and the HA 303. Connecting.

  Here, the UE 100 notifies the FAF 400 via the eNB 201 of communication control information necessary for communication connection with the IEEE 802.16e network 300 via the BS 301 in advance in order to perform the handover process. At this time, the UE 100 transmits communication control information via a virtual direct connection communication path established with the FAF 400 by tunneling processing. In addition, the FAF 400 that has received this communication control information outputs the communication control information to the ASN-GW 302 via a virtual direct communication path similarly established by the tunneling process.

  In this way, the UE 100 transmits the communication control information to the ASN-GW 302 in advance via the virtual direct connection path established by the tunneling process, so that the IEEE 100.16e network 300 via the 3GPP network 200 is transmitted. On the other hand, communication control information for performing the handover process can be notified smoothly. Therefore, it is not necessary to exchange communication control information during the handover process, and the handover process can be completed quickly.

Hereinafter, the configuration and operation of a communication system capable of executing these processes will be described. FIG. 5 is a block diagram showing functions of the UE 100 used in the communication system of the present embodiment. As shown in FIG. 5, the UE 100 includes a 3G communication unit 101 (first communication unit), an IEEE 802.16e communication unit 102 (second communication unit), a notification unit 103 (notification unit), a storage unit 104, and a handover unit. 105 (handover means), and a radio wave condition determination unit 106.
The UE 100 is a mobile device such as a mobile phone, and is realized by the hardware configuration shown in FIG. FIG. 6 is a hardware configuration diagram of the UE 100. The UE 100 shown in FIG. 6 physically includes a CPU 11, a RAM 12 and a ROM 13 as main storage devices, an input device 14 such as a keyboard and a mouse as input devices, and an output device 15 such as a display as shown in FIG. The computer system includes an auxiliary storage device 16 such as a hard disk, a 3GPP communication module 17, an IEEE 802.16e communication module 18, and the like. Each function described in FIG. 5 has the input device 14, the output device 15, and the 3GPP communication module under the control of the CPU 11 by reading predetermined computer software on the hardware such as the CPU 11 and the RAM 12 shown in FIG. 6. 17. It is realized by operating the IEEE802.16e communication module 18 and reading and writing data in the RAM 12 and the auxiliary storage device 16. Hereinafter, each functional block will be described based on the functional blocks shown in FIG.

  The 3G communication unit 101 is a part that performs communication connection with the 3GPP network 200 and wirelessly connects to the eNB 201.

  The IEEE 802.16e communication unit 102 is a part that is connected for communication with the IEEE 802.16e network 300, and is wirelessly connected to the BS 301.

  When the notification unit 103 receives a registration instruction from the eNB 201 via the 3G communication unit 101, the function information, authentication information, and network entry registration information indicating the functions (Basic Capability) supported by the UE 100 via the 3G communication unit 101 Communication control information necessary for communication connection processing, including (ID information) and service flow information (information for identifying a service, for example, communication rate, delay information, etc.) to the IEEE 802.16e network 300 On the other hand, it is a part which notifies via the 3G communication part 101. FIG. Specifically, the notification unit 103 transmits communication control information to the FAF 400 via a directly connected communication path virtually established by a tunneling process, and transmits a message defined in IEEE 802.16e to the tunneling process described above. The communication control information can be transmitted to the FAF 400 through the direct communication path established by the processing.

  The messages specified in IEEE802.16e are SSBasic Capability Request / Response Message including function information, Privacy Key Management Request / Response message including authentication information, Registration Request / Response message including network entry information, service flow DynamicService Addition Request / Response / Ack message containing information. The notification unit 103 can notify the FAF 400 of the communication control information by transmitting / receiving the request and response of each message.

  Furthermore, the notification unit 103 can transmit communication control information via a direct communication path established up to the eNB 201 by a tunneling process using RRC INFORMATION TRANSFER. That is, the notification unit 103 can perform the notification process by encapsulating the communication control information with a transmission format defined in RRCINFORMATION TRANSFER and transmitting the encapsulated communication control information to the eNB 201. A direct communication path is established between the eNB 201 and the MME 202 by tunneling processing using S1APTRANSPORT, and a direct communication path is established between the MME 202 and MME 400 using tunneling processing using L2 Tunnel. The tunneling process is executed by performing the conversion process. This tunneling process will be described in detail later.

  The storage unit 104 stores communication control information of the UE 100, and stores function information, authentication information, ID information, and connection information.

  The handover unit 105 is a part that performs processing for switching the communication connection between the eNB 201 and the BS 301, and establishes a communication connection to the BS 301 adjacent to the eNB 201 according to the result determined by the radio wave status determination unit 106. The connection process is performed as follows. Also, the BS 301 can be switched to the eNB 201.

  The radio wave condition determining unit 106 is a part that determines the radio wave condition of the IEEE 802.16e communication unit 102. When the radio wave condition determination unit 106 determines that the radio wave condition (communication quality) of the IEEE802.16e communication unit 102 is equal to or higher than a predetermined value, the IEEE802.16e communication is performed from the communication connection by the 3G communication unit 101 to the handover unit 105. The unit 102 outputs an instruction to establish communication connection.

  Next, functions of the eNB 201 will be described. FIG. 7 is a block diagram illustrating functions of the eNB 201. As illustrated in FIG. 7, the eNB 201 includes a radio unit 201a (communication means), a tunneling processing unit 201b, a network communication unit 201c, a communication quality determination unit 201d, and a handover determination unit 201e.

  The radio unit 201a is a part that is wirelessly connected to the UE 100. The radio unit 201a outputs a signal received from the UE 100 to the tunneling processing unit 201b.

  The tunneling processing unit 201b is a part that establishes a communication path through tunneling processing, and more specifically, extracts various predetermined control signals or user data from the encapsulated data received from the UE 100 by the radio unit 201a. Further, by encapsulating it in a predetermined transmission format, a virtual direct connection communication path is established. The various encapsulated data is output to the network communication unit 201c.

  The network communication unit 201c is connected to the MME 202 or Serving GW 203. The encapsulated data can be transmitted to the FAF 400 via the MME 202 or Serving GW 203.

  The communication quality determination unit 201d is a part that determines the communication quality of communication performed by the wireless unit 201a according to the 3G communication procedure. to decide. When the communication quality determination unit 201d determines that the communication quality is equal to or lower than the predetermined value, the communication quality determination unit 201d transmits an instruction signal to the UE 100 to measure the communication environment in the IEEE 802.16e communication unit 102 using the radio unit 201a. To do.

  The handover determining unit 201e is a part that determines whether or not the UE 100 needs a handover process, and makes a determination based on the measurement result indicating the communication quality in the IEEE 802.16e communication unit 102 transmitted from the UE 100. For example, if the communication quality (reception strength) indicated by the measurement result transmitted from the UE 100 is equal to or lower than a predetermined value, the handover determining unit 201e determines that a handover is necessary. Then, the handover determining unit 201e transmits a handover instruction to the UE 100 using the radio unit 201a.

  Next, a direct communication path established by a tunneling process used when the UE 100 transmits communication control information to the FAF 400 will be described. FIG. 8 is a schematic diagram showing a direct communication path established by tunneling processing. As illustrated in FIG. 8, communication control information is transmitted between the UE 100 and the eNB 201 via a direct communication path established by a tunneling process using RRC INFORMATION TRANSFER. Further, communication control information is transmitted between the eNB 201 and the MME 202 via a direct communication path established by a tunneling process using S1APNAS TRANSPORT. Further, communication control information is transmitted between the MME 202 and the FAF 400 via a direct communication path established by a tunneling process using L2 Tunnel.

  Thus, the communication control information is transmitted via the direct communication path established by the tunneling process, and a message having a different transmission format can be transmitted, and the message can be appropriately extracted at the transmission destination.

  The tunneling process will be further described. RRC INFORMATIONTRANSFER is a message format for transmitting a NAS signal (Network Access Stratum: control signal for non-radio management system). In this embodiment, various messages defined in the IEEE 802.16e communication system as a NAS signal. Is assigned. And, a message specified in IEEE802.16e, SSBasic Capability Request / Response Message including function information, Privacy Key Management Request / Response message including authentication information, Registration Request / Response message including network entry information, A Dynamic Service Addition Request / response message including service flow information is described in a transmission format defined by RRC INFORMATION TRANSFER, whereby tunneling processing is performed.

  FIG. 9 shows a schematic diagram of the transmission format. As shown in FIG. 9A, the transmission format in the downlink direction (direction from the eNB 201 to the UE 100) in the RRC INFORMATIONTRANSFER is a nas3GPP field, a cdma2000-Type field, a cdma2000-Dedicatedinfo field, an IEEE802.16e-Type field, an IEEE802. It consists of a .16e-Dedicatedinfo field.

  Further, as shown in FIG. 9B, the transmission format in the uplink direction (direction from the UE 100 to the eNB 201) in the RRC INFORMATION TRANSFER includes a nas3GPP field, a cdma2000-Type field, a cdma2000-MessageType field, a cdma2000-Dedicatedinfo field, It consists of an IEEE 802.16e-Type field and an IEEE 802.16e-Dedicated info field.

  In the present embodiment, various messages defined in IEEE 802.16e are described in the IEEE 802.16e-Dedicated info field in each transmission format in the uplink direction and the downlink direction.

  That is, in the UE 100, the SS Basic Capability Request Message that is the above-described communication control information is described in the IEEE 802.16e-Dedicated info field illustrated in FIG. 9A and transmitted to the eNB 201. Also, in the eNB 201, an SSBasic Capability Response Message that is a response is described in the IEEE 802.16e-Dedicated info field shown in FIG. 9B and transmitted to the UE 100. Thereby, function information is transmitted to eNB201 (FAF400 and AGN-GW302), and the response signal is transmitted to UE100.

  Similarly, a Privacy Key Management Request message including authentication information, a Registration Request message including network entry information, and a Dynamic Service Addition Request message including service flow information are respectively described in the IEEE 802.16e-Dedicated info field and transmitted. The response is a PrivacyKey Management Response message including authentication information, a Registration Response message including network entry information, and a Dynamic Service Addition Response message including service flow information described in the IEEE802.16e-Dedicatedinfo field and transmitted to the UE 100. Is done.

  Next, the transmission format of S1AP NAS TRANSPORT will be described. S1APNAS TRANSPORT is a transmission format for transmitting a NAS signal, similar to RRC INFORMATION TRANSFER. As shown in FIG. 10A, the transmission format in the downlink direction includes a MessageType field, an MME UE S1AP ID field, an eNB UE S1AP ID field, a NAS-PDU field, a Serving PLMN field, and a Handover Restriction List field. As shown in FIG. 10B, the transmission format in the uplink direction includes a Message Type field, an MMEUE S1AP ID field, an eNB UE S1AP ID field, and a NAS-PDU field.

  In the present embodiment, control signals defined in the IEEE 802.16e communication system are described in the NAS-PDU field in each transmission format in the uplink direction and the downlink direction. That is, an SS-Basic Capability Request Message, a Privacy Key Management Request message, a Registration Request message, and a Dynamic Service Addition Request message are described in the NAS-PDU field in the uplink-direction transmission format, and the NAS-PDU field in the downlink-direction transmission format. The response includes SSBasic Capability Response Message, Privacy Key Management Response message, Registration Response message, and Dynamic Service Addition Response message. A packet in a transmission format in which each message is described is transmitted / received.

  Returning to FIG. 8, the description will continue. The UE 100 transmits, to the eNB 201, each message defined in IEEE 802.16e, which is handled as a NAS signal using RRC INFORMATIONTRANSFER. The eNB 201 extracts a NAS signal from the transmission format defined by RRCINFORMATION TRANSFER, and transmits the NAS signal to the MME 202 using S1AP NAS TRANSPORT. The MME 202 extracts a NAS signal from the transmission format defined by S1APNAS TRANSPORT, and transmits it to the FAF 404 using the L2 Tunnel. The FAF 404 can further transmit a NAS signal to the BS 301 using GRETunnel.

  By such a tunneling process, a control signal defined by IEEE802.16e can be transmitted via the 3G network 200.

  Next, the transmission format of L2 Tunnel will be described. FIG. 11 is a schematic diagram showing a transmission format of L2Tunnel. As shown in FIG. 11, the L2 Tunnel transmission format includes a Layer 2 field, an IP field, a UDP field, and an L2TP field (PPP field, IP field, TCP / UDP field, Data field). Various messages specified in .16e are described in the Data field.

  Further, a transmission format of GRE (Generic Routing Encapsulation) Tunnel will be described. FIG. 12 is a schematic diagram showing a GRETunnel transmission format. As shown in FIG. 12, the GRE Tunnel transmission format includes an IP field and a GRE field, and this GRE field includes an IP field, a TCP field, and an HTTP field. Various messages are described in the HTTP field.

  Next, an operation when the UE 100 performs a handover process from the 3GPP network 200 to the IEEE 802.16e network 300 will be described. FIG. 13 is a sequence diagram of a handover process using a message defined in IEEE 802.16e.

  When the UE 100 enters the communication range of the eNB 201 and performs location registration processing, function information with the IEEE 802.16e function is registered on the 3GPP network 200 side (S101). Note that when the eNB 201 falls within the communication range due to handover, the function information is registered from the handover source eNB. Then, in the UE 100, the 3G communication unit 101 performs data communication or voice call with the UE 100x that is the communication partner via the Serving GW 203 (S102). When the eNB 201 receives function information with the IEEE 802.16e function and determines that a BS that is an IEEE 802.16e base station exists in the neighboring cell information of the eNB 201, the eNB 201 performs advance handover for the UE 100 in advance. RRCCONNECTION RECONFIGURATION indicating that registration processing is to be performed is output (S103).

  When receiving the RRC CONNECTIONRECONFIGURATION indicating the pre-registration process, the UE 100 determines that the pre-registration process is performed by the notification unit 103 (S104), and performs the pre-registration process (S105). In this notification unit 103, tunneling processing is performed with the eNB 201 by RRCINFORMATION TRANSFER, and pre-registration processing is performed through this RRC INFORMATION TRANSFER. Moreover, in eNB201, a prior registration process is performed via S1APNAS TRANSPORT. In the MME 202, pre-registration processing is performed using the L2 Tunnel.

  Thus, via the communication path established by the tunneling process, SS Basic Capability Request / Response Message (SBC-REQ / RSP in FIG. 13), Privacy Key Management Request / Response message (PKMv2-REQ / RSP in FIG. 13), Registration Request / Response message (REG-REQ / RSP in FIG. 13) and Dynamic Service Addition Request / Response / Ack message (DSA-REQ / RSP / ACK in FIG. 13) are transmitted and received. Here, REQ indicates a request signal, RSP indicates a response signal thereof, and ACK indicates an affirmative signal with respect to the response signal.

  Therefore, the communication control information pre-registration process via the 3G network 200 is performed between the UE 100 and the FAF 400 by transmitting and receiving a message defined by IEEE 802.16e via the direct communication path established by the tunneling process. Can be done smoothly.

  In FAF 400, authentication processing is performed on AAA 600 based on the received pre-registration information. An authentication process is performed between the FAF 400 and the AAA 600 via a direct communication path established by a tunneling process using a GRE Tunnel (S105x).

  After the pre-registration process is performed, the eNB 201 measures the communication quality (reception strength, S / N ratio, etc.) in the 3G communication unit 101 by the communication quality determination unit 201d, and determines that the communication quality has deteriorated ( (S106), RRC CONNECTION RECONFIGURATION indicating a communication quality measurement instruction of the IEEE 802.16e communication unit 102 is transmitted to the UE 100 using the radio unit 201a (S107).

  In the UE 100, when a measurement instruction is received by the 3G communication unit 101, an instruction signal is output to the IEEE802.16e communication unit 102 to start (S108). In the IEEE802.16e communication unit 102, the power is turned on, the communication quality is measured by the radio wave condition determining unit 106 (S109), and the measurement result is output by the radio wave condition determining unit 106 (S110). Here, since the measurement result that the radio wave condition is good is output, the handover determination unit 201e determines the handover process to the IEEE 802.16e communication (S111).

  When the handover process is determined, the handover determination unit 201e outputs a handover instruction to the UE 100. A direct communication path is established between the UE 100 and the eNB 201 by tunneling processing using RRC INFORMATION TRANSFER, and a direct communication path is established between the eNB 201 and MME 202 by tunneling processing using S1APNAS TRANSPORT. Furthermore, a direct communication path is established by tunneling processing using the L2 Tunnel, and a control signal (HO-REQ) for handover processing between the UE 100 and the FAF 400 is established through these established direct communication paths. / RSP, HO-IND) is transmitted / received (S112). Then, processing for handover processing is performed between the FAF 400 and the ASN-GW 302 via a direct communication path established by tunneling processing using GRETunnel (S112x).

  When these handover processes are performed, the UE 100 performs a switching process from the 3G communication unit 101 to the IEEE 802.16e communication unit 102 (S113), performs transmission / reception of RNG-REQ / RSP, and the UE 100 and the BS 301 are in communication connection. This completes the handover process (S115).

  Instead of the sequence diagram in FIG. 13, the sequence diagram shown in FIG. 14 may be used. That is, the message passing through the direct communication path established by the tunneling process in S105 may be a unique message that is replaced with a message defined by IEEE 802.16e. For example, as an original message, one request signal, IEEE802.16eCONTEXT TRANSFER REQUEST, SS Basic Capability Request Message (SBC-REQ in FIG. 13), PrivacyKey Management Request message (PKMv2-REQ in FIG. 13), Registration Request message ( A message including REG-REQ in FIG. 13 and Dynamic Service Addition Request message (DSA-REQ in FIG. 13) may be used.

  In this case, the IEEE802.16e CONTEXTTRANSFER RESPONSE that is the response message includes an SS Basic Capability Response Message (SBC-RSP in FIG. 13), a PrivacyKey Management Response message (PKMv2-RSP in FIG. 13), and a Registration Response message (REG in FIG. 13). -RSP), DynamicService Addition Response message (DSA-RSP in FIG. 13).

  The IEEE802.16e CONTEXT TRANSFER CONFIRM is a message including a Dynamic Service Addition Ack message. By using these unique messages, the sequence processing can be reduced.

  Next, FIG. 14 shows a sequence diagram illustrating a handover process using the above-described unique message. In S105a in FIG. 14, a tunneling process using RRC INFORMATION TRANSFER is performed between the UE 100 and the eNB 201, a tunneling process using S1AP NASTRANSPORT is performed between the eNB 201 and the MME 202, and the MME 202 and the FAF 400 Between them, tunneling processing using L2 Tunnel is performed. In the communication path established by the tunneling process, one IEEE802.16eCONTEXT TRANSFER REQUEST including all of the above-mentioned various messages is transmitted from the UE 100 to the FAF 400, and the response from the FAF 400 to the UE 100 is received. A certain IEEE802.16eCONTEXT TRANSFER RESPONSE is transmitted. Then, IEEE802.16e CONTEXTTRANSFER CONFIRM is transmitted from the UE 100 to the FAF 400.

  Thereby, in IEEE802.16e, it is possible to reduce the exchange of signals that have been performed in 5.5 round trips to 1.5 round trips, thereby reducing communication traffic and processing of various devices including the UE 100. The load can be reduced.

  Next, a modification of this embodiment will be described. In the above-described embodiment, the process is performed using C-Plane, but may be performed using U-Plane instead. FIG. 15 is a schematic diagram of a communication path established by tunneling processing when U-Plane is used.

  As illustrated in FIG. 15, the UE 100 has established a virtual communication path directly connected to the FAF 400 via the eNB 201 and the S-GW 203 by a tunneling process. Here, a direct communication path is established by tunneling processing using IP Tunnel, and a communication path via S-GW 203 is established because U-Plane is used. In this modification, SS Basic Capability Request / Response Message (SBC-REQ / RSP in FIG. 13), Privacy Key Management Request / Response message (FIG. 13) are established via a direct connection communication path established by tunneling processing using IPTunnel. PKMv2-REQ / RSP), Registration Request / Response message (REG-REQ / RSP in FIG. 13), and Dynamic Service Addition Request / Response / Ack message.

  FIG. 16 shows a sequence diagram of the communication system in this modification. The difference from the present embodiment is that a message is transmitted on the U-Plane via the S-GW 203 in the processes of S105b and S112b. Therefore, IP Tunnel, which is a tunneling process that can pass user data, is used. More specifically, in the UE 100, the notification unit 103 establishes a direct communication path with the FAF 400 by a tunneling process using an IP Tunnel, and transmits the user data (on the U-Plane) according to the above-described IEEE802.16e. The specified message is sent and received.

  Also, as shown in S112b in FIG. 16, a direct connection communication path is established by the IP Tunnel between the UE 100 and the FAF 400, and HO-REQ / RSP and HO− which are control signals for performing a handover process. The IND is transmitted / received between the FAF 400 and the UE 100 via this communication path as user data of an IP packet.

  In this manner, messages can be transmitted and received as user data between the UE 100 and the FAF 400, and messages can be exchanged between networks having different message forms of control signals.

  Instead of the sequence diagram in FIG. 16, the sequence diagram shown in FIG. 17 may be used. That is, the message passing through the direct communication path established by the tunneling process in S105b may be a unique message that is replaced with a message defined by IEEE 802.16e. For example, as a unique message, an IEEE802.16eCONTEXT TRANSFER REQUEST that is one request signal, an SS Basic Capability Request Message (SBC-REQ in FIG. 16), a PrivacyKey Management Request message (PKMv2-REQ in FIG. 16), a Registration Request message ( A message including a REG-REQ in FIG. 16 and a Dynamic Service Addition Request message (DSA-REQ in FIG. 16) may be used.

  In this case, the IEEE802.16e CONTEXTTRANSFER RESPONSE that is the response message includes an SS Basic Capability Response Message (SBC-RSP in FIG. 16), a PrivacyKey Management Response message (PKMv2-RSP in FIG. 16), and a Registration Response message (REG in FIG. 16). -RSP), DynamicService Addition Response message (DSA-RSP in FIG. 16).

  The IEEE802.16e CONTEXT TRANSFER CONFIRM is a message including a Dynamic Service Addition Ack message. By using these unique messages, the sequence processing can be reduced.

  Next, FIG. 17 shows a sequence diagram showing a handover process using the above-described unique message. In S105c in FIG. 17, a tunneling process using IP Tunnel is performed between the UE 100 and the FAF 400. Then, the IEEE802.16eCONTEXT TRANSFER REQUEST is transmitted from the UE100 to the FAF400 on the direct communication path established by the tunneling process, and the response IEEE802.16eCONTEXT TRANSFER RESPONSE is transmitted from the FAF400 to the UE100. . Then, IEEE802.16e CONTEXTTRANSFER CONFIRM is transmitted from the UE 100 to the FAF 400.

  Thereby, in IEEE802.16e, it is possible to reduce the exchange of signals that have been performed in 5.5 round trips to 1.5 round trips, thereby reducing communication traffic and processing of various devices including the UE 100. The load can be reduced.

  Next, operational effects of the communication system in the present embodiment and the modification will be described. In this communication system, the notification unit 103 performs a virtual direct connection communication path established between the UE 100 and the AGN-GW 302 by a tunneling process while the UE 100 is performing communication using the 3G communication unit 101. Communication control information for handover processing is notified to the IEEE 802.16e network 300 (AGN-GW 302) side. The handover unit 105 omits the communication control information notification process and executes the handover process. And BS301 can perform the communication process with respect to the handover process from UE100 using the communication control information notified in advance. Accordingly, smooth communication control information notification can be performed before the handover process between different communication methods, for example, between 3GPP communication and IEEE 802.16e communication. Therefore, smooth handover processing can be executed without exchanging communication control information during the handover processing.

  Furthermore, in the communication system of the present embodiment, the notification unit 103 of the UE 100 transmits and receives communication control information to and from the FAF 400 via the direct communication path, thereby transmitting and receiving communication control information to the FAF 400. Can be notified. For example, the communication control information can be notified by transmitting / receiving an SS Basic Capability Request / Response Message, a Privacy Key Management Request / Response message, a Registration Request / Response message, and a Dynamic Service Addition Request / Response / Ack message.

  The FAF 400 can extract communication control information from a message defined by IEEE 802.16e, and can notify the extracted communication control information to the IEEE 802.16e network 300 (AGN-GW 302) via a direct communication path. . Accordingly, smooth communication control information notification between different communication methods can be performed before the handover process.

  Here, in the communication system of the present embodiment, the notification unit 103 of the UE 100 notifies the communication control information by C-Plane (call control signal plane), thereby reliably executing the communication control information notification process. Can do. Moreover, as a modification, when the notification unit 103 notifies the communication control information using U-Plnae (user information transfer plane), the notification process of the communication control information can be realized by a simple process.

  In the communication system according to the present embodiment, the notification unit 103 transmits one request signal including communication control information to the FAF 400 via the communication path, receives the response signal, and responds to the response signal. By sequentially transmitting confirmation signals for confirmation, it is possible to notify the FAF 400 of communication control information. For example, communication control information can be notified by using IEEE802.16e CONTEXT TRANSFER REQUEST, IEEE802.16e CONTEXT TRANSFERRESPONSE, and IEEE802.16e CONTEXT TRANSFER CONFIRM as unique messages.

  The FAF 400 transmits an IEEE802.16e CONTEXT TRANSFER REQUEST that is a response signal to the IEEE802.16eCONTEXT TRANSFER REQUEST that is a request signal transmitted from the notification unit 103, and also receives communication control information from the IEEE802.16e CONTEXT TRANSFER REQUEST. The extracted communication control information can be notified to the IEEE 802.16e network 300 (AGN-GW 302) side.

DESCRIPTION OF SYMBOLS 100 ... Mobile device, 101 ... Communication part, 102 ... Communication part, 103 ... Notification part, 104 ... Memory | storage part, 105 ... Handover part, 106 ... Radio wave condition judgment part, 200 ... 3GPP network, 201a ... Radio | wireless part, 201b ... Tunneling Processing unit, 201c, network communication unit, 201d, communication quality determination unit, 201e, handover determination unit, 300, IEEE 802.16e network, 400, FAF, 500, other communication network.

Claims (8)

In a communication system comprising a first base station arranged in one communication network of one communication method, a second base station arranged in another communication network of another communication method, and a mobile device ,
The mobile device is
First communication means for executing a communication method via the first base station;
Second communication means for executing another communication method via the second base station;
Virtual direct communication established between the mobile device and the other communication network by tunneling processing prior to handover processing to the second base station during communication by the first communication means A notification means for notifying the other communication network side of communication control information necessary for communication connection processing via a path;
After the notification process by the notification means, a handover means for starting the handover process from the first base station to the second base station by omitting the communication control information notification process;
With
The second base station is
When the handover process by the handover unit in the mobile device is completed, a communication unit that executes a communication process with the mobile device using the communication control information notified by the notification unit;
A communication system comprising: A handover control device for connecting the first base station and the second base station;
The notification means sequentially transmits / receives a request signal and a response signal corresponding to each of a plurality of communication control information to / from the handover control apparatus via the direct communication path, thereby transmitting the plurality of communication control information. All of the above to the handover control device,
The handover control apparatus extracts communication control information from a control signal defined in another communication method, and notifies the extracted communication control information to the other communication network side through the direct connection communication path. The communication system according to claim 1.   The communication system according to claim 2, wherein the notification means notifies communication control information using a call control signal plane.   The communication system according to claim 2, wherein the notification unit notifies communication control information using a user information transfer plane. A handover control device for connecting the first base station and the second base station;
The notifying means transmits and receives one request signal including a plurality of communication control information, receives the response signal, and confirms the response signal with the handover control apparatus via the communication path. By sequentially transmitting confirmation signals, the communication control information is notified to the handover control device,
The handover control device transmits a response signal to the request signal transmitted from the notification means, extracts communication control information from the request signal, and transmits the extracted communication control information to the other network side The communication system according to claim 1, wherein transmission is performed.   6. The communication system according to claim 5, wherein the notification unit notifies communication control information using a call control signal plane.   The communication system according to claim 5, wherein the notification unit notifies communication control information using a user information transfer plane. Handover method using first base station arranged in one communication network of one communication method, second base station arranged in another communication network of another communication method, and mobile device In
A virtual direct connection established between the mobile device and the other communication network by a tunneling process prior to a handover process to the second base station during communication with the first base station. A notification step of notifying the other communication network side of communication control information necessary for communication connection processing via a communication path;
After the notification process by the notification step, the handover step of starting the handover process from the first base station to the second base station by omitting the communication control information notification process;
A communication step of executing a communication process for the handover process from the mobile station using the communication control information notified by the notification step when the handover process is completed in the handover step of the mobile station;
A handover method comprising:

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