JP2005260435A - Mobile communication system and radio network control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile communication system and a radio network control method for preventing the occurrence of a packet loss and deterioration in the communication quality. <P>SOLUTION: In a DRNC 53c, an RNC control section 104 sets an execution time of SRNS Relocation and transmits a Drift RNC Setup Request message including the notice of the setting execution time of the SRNS Relocation to a SRNC 53a (step ST 304). Then the SRNC 53a receiving the Drift RNC Setup Request sets an Iur bearer and uses an FP section 108 to set the execution time of the SRNS Relocation, and thereafter transmits a Drift RNC Setup Response message to the DRNC 53c (step ST 305). Further, when the execution time of the SRNS Relocation designated by a CFN comes, the SRNC 53c, the DRNC 53b, and the DRNC 53c execute the SRNS Relocation according to an instruction of the FP section 108. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a mobile communication system and a radio network control method, and more particularly to a mobile communication system and a radio network control method for performing a network function handover in a mobile communication network.

  FIG. 4 is a configuration diagram showing a mobile communication system to which a conventional GPRS (General Packet Radio Service) mobile communication packet system is applied (for example, Non-Patent Document 1).

  The mobile communication system shown in FIG. 4 is a serving radio network that controls a mobile terminal (hereinafter referred to as “MS”) 11 and base station apparatuses (hereinafter referred to as “NodeB”) 12a to 12c in a control area # 401. Control device (hereinafter referred to as “SRNC”) 13a, radio network control device (hereinafter referred to as “RNC”) 13b for controlling NodeBs 12d to 12f in control area # 402, serving for performing communication by GPRS GPRS support nodes (hereinafter referred to as “SGSN”) 14a and 14b, gateway GPRS support nodes (hereinafter referred to as “GGSN”) 15 for performing communication by the GPRS method, mobile switching devices (hereinafter referred to as “MSC / VLR”) 16a, 16b and the home location device / authentication center Terpolymers (hereinafter referred to as "HLR / AuC") has a 17. Here, the SRNC performs serving radio network control related to the MS, such as radio channel control of the MS communicating with the NodeB.

  In a mobile communication system, a communication method called subscriber line extension is applied. In the subscriber line extension method, for example, when the MS 11 is handed over from the location registration area configured by the NodeB 12a under the SRNC 13a to the location registration area configured by the NodeB 12e under the RNC 13b, the signal between the MS 11 and the GGSN 15 is As shown in FIG. 4, the data is transferred through the route of MS 11, NodeB 12 e, RNC 13 b, SRNC 13 a, SGSN 14 a, and GGSN 15.

  At this time, the macro diversity combining function, the wireless layer 2 function such as MAC and RLC, and the wireless layer 3 function such as RRC / RRM are still provided by the SRNC 13a. That is, the subscriber's access line is extended with the SRNC 13a as an anchor point.

  However, in the case of the communication form of FIG. 4, since the access line of the subscriber is extended with the SRNC 13a as an anchor point, there is a problem that a redundant communication path is formed and communication resources of the mobile communication network cannot be used efficiently. In order to solve such a problem, an SRNS Relocation method is known (for example, Non-Patent Document 2). The SRNS Relocation method is a method for handing over the SRNC function between radio network controllers. Here, the network function handover is a process of switching SRNCs (specific stations) that collectively process data in control areas # 401 and # 402 of each RNC.

  By applying the SRNS Relocation method, as shown in FIG. 5, the SRNC 13a becomes the RNC 18a, and the RNC 13b becomes the SRNC 18b. For example, in FIG. 4, when the MS 11 is handed over from the location registration area configured by the NodeB 12a under the SRNC 13a to the location registration area configured by the NodeB 12e under the RNC 13b, the MS 11 and the GGSN 15 As shown in FIG. 5, signals between and are transferred through the routes of MS11, NodeB 12e, SRNC 18b, SGSN 14b, and GGSN 15, eliminating redundant communication routes and efficiently using communication resources of the mobile communication network. It becomes possible to do.

  Furthermore, as another method of the mobile communication system to which the conventional GPRS mobile communication packet method is applied, as shown in FIGS. 6 and 7, as an SRNS Relocation method when the MS is communicating with a plurality of RNCs, Enhanced SRNS Relocation is known (for example, Non-Patent Document 3).

  The mobile communication system shown in FIG. 6 is described as a SRNC 53a that controls NodeBs 52a to 52c in control area # 601 and a drift radio network controller (hereinafter referred to as “DRNC”) that controls NodeBs 52d to 52f in control area # 602. ) 53b, DRNC 53c for controlling the NodeBs 52g to 52i in the control area # 603, SGSN 54, MSC / VLR 55 and GGSN 56 for performing communication by the GPRS method. Here, the DRNC performs controlling radio network control (CRNC) related to the radio cell such as resource management in the radio cell of the NodeB.

  For example, in FIG. 6, regarding the uplink direction, by executing SRNS Relocation, as shown in FIG. 7, the SRNS function is handed over to the network function to change SRNC 53a to DRNC 61a and DRNC 53c to SRNC 61b. . As a result, the DRNC 61a changed from the SRNC 53a switches from receiving packets from the DRNC 53b and DRNC 53c to transmitting packets to the SRNC 61b. Also, the DRNC 53b switches from transmitting the packet to the SRNC 53a to transmitting the packet to the SRNC 53c. Furthermore, the SRNC 61b changed from the DRNC 53c switches from receiving the packet to the SRNC 53a so as to receive the packet from the DRNC 61a and the DRNC 53b. In this way, by applying Enhanced SRNS Relocation, even when the MS is communicating with a plurality of RNCs, the SRNS function is handed over to the network function, the redundant path is eliminated, and the communication resource of the mobile communication network Can be used efficiently.

  Regarding the downlink direction, the SRNC 53a receives a packet from the SGSN 54 before executing SRNS Relocation, and duplicates and transmits the received packet to the NodeB 52c, DRNC 53b, and DRNC 53c. However, after executing SRNS Relocation, the SRNC 61b It is necessary to switch to transmit the packet received from the node B 52c. Further, the DRNC 53b transmits the packet received from the SRNC 53a to the NodeB 52e before the execution of the SRNS Relocation. However, after executing the SRNS Relocation, the DRNC 53b switches to receive the packet from the SRNC 61b and transmit it to the NodeB 52e. Furthermore, the DRNC 53c transmits the packet received from the SRNC 53a to the NodeB 52g before executing the SRNS Relocation. However, after executing the SRNS Relocation, the DRNC 53c receives the packet from the SGSN 62 and duplicates the received packet to the DRNC 61a, the DRNC 53b, and the Node B 52g. And need to send.

Conventionally, there is a connection frame number (hereinafter referred to as “CFN”) as a signal used for timing control for data transfer between the NodeB and the RNC. The CFN is a value representing the signal transmission timing in the radio section of the W-CDMA system, and the CFN timing is synchronized between the RNC and the NodeB under the RNC. For example, in the uplink, the NodeB adds the CFN as the reception time to the data received from the UE and sends it to the RNC, and the RNC determines that the data of the same CFN is the same data and receives it from the plurality of NodeBs. Select high quality data from the collected data. On the other hand, in the downlink, the RNC adds CFN to the data and sends it to the subordinate NodeB, which transmits the data to the UE at the timing of the CFN added to the received data. Thereby, several NodeB can transmit the same data to UE at the same time.
3GPP, TS23.060 General Packet Radio Service (GPRS) Service description; Stage 2 3GPP TR 25.832 V4.0.0 (2001-03) “Manifestations of Handover and SRNS Relocation (Release 4)” 3GPP TSG RAN-WG3 R3-021639 TR03.010 “SRNS relocation enhancement” (v0.4.0)

  However, in the conventional mobile communication system and radio network control method, there is a problem that when SRNS Relocation is executed to switch the communication path between RNCs, packet loss occurs and communication quality deteriorates. For example, in FIG. 7, a packet received by the NodeB 52a at the same time may be transferred via the route shown in FIG. 6 or transferred via the route shown in FIG. is there. Furthermore, when a mobile communication system that needs to frequently execute SRNS Relocation is used, there is a problem that communication quality deterioration due to packet loss becomes significant.

  The present invention has been made in view of this point, and an object thereof is to provide a mobile communication system and a radio network control method capable of preventing packet loss and preventing deterioration of communication quality.

  In the radio network control method of the present invention, the network function handover is a process of switching the radio control device to be a specific station that collectively processes data from base station devices in the control area of all radio control devices, When permitted by the upper station apparatus of the radio network controller, the radio network controller performs the network function handover at the same time in the radio network controller based on a timing control signal for controlling the network function handover timing. The specific station is switched at.

  According to this method, since all the radio control apparatuses perform network function handover at the same time based on the timing control signal, the radio control apparatus uses different paths for the packet data before the network function handover and after the network function handover. Loss of packet data due to arriving at can be prevented, and deterioration of communication quality can be prevented.

  In the radio network control method of the present invention, in the method, a signal for controlling timing between the radio control apparatus which is the specific station and a terminal apparatus is used as the timing control signal.

  According to this method, in addition to the above-described effects, the timing of network function handover can be controlled using a signal for controlling timing between a radio control apparatus and a terminal apparatus that are specific stations. A new signal for controlling the timing of the network function handover is unnecessary, and the network function handover process can be simplified.

  The radio controller of the present invention is a radio controller that serves as a serving radio network controller that is a specific station by performing a network function handover that is a process of switching specific stations that collectively process control area data of each station, Timing determining means for determining timing for performing the network function handover based on a timing control signal for controlling timing of the network function handover, and notification means for notifying the other station of the timing determined by the timing determining means; The network function handover is performed at the timing determined by the timing determination means, thereby stopping the transfer of data in the control area of the own station to the other station and transferring the data in the control area of the other station from the other station. Switch to be A data transfer control means, and a data processing means for processing data in the control area of the local station and data in the control area of the other station transferred from the other station after becoming the specific station. take.

  According to this configuration, when the network function handover is performed to serve as a serving radio network controller, the network function handover timing is determined and notified to the other station, and the network function handover is performed simultaneously with the other station. The packet data can be prevented from being lost due to the packet data reaching the radio control device through a route different from the route before the network function handover and the route after the network function handover, and the communication quality can be prevented from deteriorating. it can.

  The radio network controller according to the present invention employs a configuration in which, in the configuration, the timing determination unit uses a signal for controlling timing between the specific station and the terminal device as the timing control signal.

  According to this configuration, in addition to the above effects, the network function handover timing can be controlled using a signal for controlling the timing between the specific station and the terminal device. No new signal is required to control the network function, and the network function handover process can be simplified.

  The radio control apparatus of the present invention performs network function handover, which is a process of switching specific stations that collectively process data in the control area of each station, and transfers data from the specific station that is a serving radio network control apparatus to the specific station A wireless control device that switches to a drift wireless network control device, and a data processing means for processing the control area data of the local station and the control area data of the other station transferred from the other station in the case of the specific station; An acquisition means for newly acquiring a timing control signal for controlling the timing of the network function handover from the other station serving as the specific station, and the other station based on the timing control signal acquired by the acquisition means. The control area of the other station by simultaneously handing over the network function A data transfer control means for stopping transfer of data from the other station to the own station and switching so that the data in the control area of the own station is newly transferred to the other station as the specific station Take.

  According to this configuration, when switching from the serving radio network controller to the drift radio network controller by performing a network function handover, a notification from another station that newly becomes the serving radio network controller before the network function handover is made. Since the network function handover is performed simultaneously with other stations at the timing of the network function handover performed, the packet data must reach the radio control apparatus through a different path between the path before the network function handover and the path after the network function handover. Can prevent packet data loss and also prevent degradation of communication quality.

  The radio network controller according to the present invention transfers data to the specific station of the change destination every time the specific station is changed by performing a network function handover, which is a process of switching specific stations that collectively process control area data of each station. A radio control apparatus that is a drift radio network control apparatus that acquires a timing control signal for controlling the timing of the network function handover from the other station that is newly the specific station by performing the network function handover And switching so that the data in the control area of the local station is transferred to the specific station to be changed by performing the network function handover simultaneously with the other station based on the timing control signal acquired by the acquisition unit And a data transfer control means.

  According to this configuration, when the network function handover is performed so that the drift radio network control apparatus remains, the network function handover timing notified from the serving radio network control apparatus of the other station simultaneously with the other station Since network function handover is performed, loss of packet data due to packet data reaching the radio controller via a different path between the path before the network function handover and the path after the network function handover can be prevented. Can be prevented.

  The radio network controller according to the present invention employs a configuration in which the acquisition unit acquires the timing control signal using a signal for controlling timing between the specific station and the terminal device.

  According to this configuration, in addition to the above effects, the network function handover timing can be controlled using a signal for controlling the timing between the specific station and the terminal device. No new signal is required to control the network function, and the network function handover process can be simplified.

  The mobile communication system of the present invention includes a mobile station, a base station apparatus that transmits and receives data between the mobile terminals, and a specific station that collectively processes data from the base station apparatus in the control area of all other stations Whether to allow the network function handover to be performed to a plurality of radio control apparatuses that perform network function handover, which is a process of switching between, and the radio control apparatus that requests permission to become the specific station by the network function handover A higher-level station apparatus that determines whether or not the network function handover is permitted in the higher-level station apparatus, a timing control signal for controlling a timing of the network function handover. Based on the network function hand at the same time in all the radio control device Adopt a configuration in which over server.

  According to this configuration, since all the radio control devices perform network function handover at the same time based on the timing control signal, the radio control device is configured so that packet data has different paths between the path before the network function handover and the path after the network function handover. Loss of packet data due to arriving at can be prevented, and deterioration of communication quality can be prevented.

  The mobile communication system of the present invention is configured such that, in the above configuration, the radio control device uses a signal for controlling timing between the radio control device, which is the specific station, and a terminal device as the timing control signal. Take.

  According to this configuration, in addition to the above-described effect, it is possible to control the timing of network function handover using a signal for controlling the timing between the radio control device that is a specific station and the terminal device. A new signal for controlling the timing of the network function handover is unnecessary, and the network function handover process can be simplified.

  According to the present invention, it is possible to prevent packet loss and to prevent deterioration in communication quality.

  The inventor has focused on the fact that the CFN is maintained as timing information between the Node B and the SRNC, and has reached the present invention.

  The gist of the present invention is based on a timing control signal (CFN) that controls the timing of network function handover, which is a process of switching a specific station (SRNC) that collectively processes data in the control area of all radio control devices. In other wireless control devices, network function handover is performed simultaneously, and a specific station is switched by the wireless control device.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment)
FIG. 1 is a block diagram showing a configuration of radio control apparatus 100 according to the embodiment of the present invention.

  The line I / F units 101-1 to 101-n output the Iub frame signal input from the switching unit 109 to each NodeB. Also, the line I / F units 101-1 to 101-n output the Iub frame signal input from each NodeB to the switching unit 109.

  The line I / F unit 102 outputs the Iur frame signal input from the switching unit 109 to another RNC. Further, the line I / F unit 102 outputs the Iur frame signal input from another RNC to the switching unit 109. Further, when radio control apparatus 100 is handed over to a network function to become a new SRNC (hereinafter referred to as “new SRNC”), line I / F unit 102 starts from switching section 109 before handing over the network function. The CFN, which is the input network function handover timing information, is output to another RNC. In addition, the line I / F unit 102 is used when the radio network controller 100 is handed over to the network function to change from SRNC to DRNC (hereinafter referred to as “new DRNC”), and when the network function hand-over remains DRNC. Before the network function handover, the CFN, which is the network function handover timing information sent from another RNC serving as the new SRNC, is output to the switching section 109.

  The line I / F unit 103 outputs the user frame signal input from the switching unit 109 to the SGSN / MSC. Further, the line I / F unit 103 outputs a user frame signal input from the SGSN / MSC to the switching unit 109.

  The RNC control unit 104 performs control protocol processing with the Node B, performs control protocol processing using a signal input from the switching unit 109, and transmits the signal subjected to control protocol processing to the switching unit. To 109. In addition, when radio control apparatus 100 becomes a new SRNC, RNC control unit 104 reads CFN (timing control signal) from timing source unit 110 at a predetermined timing before performing network function handover, and performs network function handover. Is output to the FP unit 108 as timing information, and is also output to the exchange unit 109 to notify the other RNCs of CFN as timing information for network function handover. In addition, when the radio network controller 100 becomes a new DRNC or remains in the DRNC, the RNC control unit 104 performs a network function handover timing notified from another RNC that becomes the new SRNC input from the switching unit 109. The timing for executing the SRNS Relocation is set from the CFN that is the information of the CNS, and the CFN as the timing information for executing the set SRNS Relocation is output to the FP unit 108.

  The radio layer 3 unit 105 performs radio resource (hereinafter referred to as “RRC”) processing and radio resource management (hereinafter referred to as “RRM”) with the MS based on the control signal input from the exchange unit 109. Process. Radio layer 3 section 105 outputs control data for RRC to exchanging section 109.

  The radio layer 2 unit 106 performs media access control (hereinafter referred to as “MAC”) processing and radio link control (hereinafter referred to as “RLC”) processing on user data and control data input from the exchange unit 109. And output to the exchanging unit 109. The radio layer 2 unit 106 performs error recovery processing by retransmission on the Iur frame signal input from the exchange unit 109. Then, after performing error recovery processing, radio layer 2 section 106 separates it into a user frame signal and a control frame signal, and outputs them to switching section 109.

  In the diversity handover state, the MDC unit 107 refers to the CFN included in the user frame signal input from the switching unit 109, determines that the same CFN signal is a signal of the same data, and has the better quality. Select a signal. In addition, MDC section 107 adds CFN to the user frame signal and outputs the signal to switching section 109. Further, after executing SRNS Relocation, MDC section 107 performs macro diversity combining on the Iur frame signal or Iub frame signal input from switching section 109 based on CFN.

  The FP unit 108 receives the CFN input from the RNC control unit 104 and the Iur frame signal or Iub frame input from the switching unit 109 at every predetermined timing when the Iur frame signal or Iub frame signal is input from the switching unit 109. Compare with CFN set in signal. If the comparison result indicates that it is the timing to execute SRNS Relocation, the FP unit 108 changes the transfer destination of the Iub frame signal or the Iur frame signal and outputs the changed signal to the exchange unit 109. Details of the FP unit 108 will be described later.

  The switching unit 109 outputs the Iub frame signal input from the FP unit 108 to the line I / F units 101-1 to 101-n or the MDC unit 107, and the Iur frame signal input from the FP unit 108 to the line I / F. The signal is output to F section 102 or MDC section 107, and the user frame signal input from radio layer 2 section 106 is output to line I / F section 103. Further, switching section 109 outputs the Iub frame signal in which the CFN input from line I / F sections 101-1 to 101-n is set to FP section 108, and the CFN input from line I / F section 102 The set Iur frame signal is output to the FP section 108. The switching unit 109 outputs the signal input from the RNC control unit 104 to the line I / F units 101-1 to 101-n to perform control protocol processing, and the line I / F units 101-1 to 101- The signal input from n is output to the RNC control unit 104 for processing the control protocol. Further, switching section 109 outputs CFN, which is the network function handover timing information input from RNC control section 104, to line I / F section 102, and the network function handover timing input from line I / F section 102. The CFN that is information is output to the RNC control unit 104. Further, switching section 109 outputs the control frame signal input from radio layer 2 section 106 to radio layer 3 section 105 and outputs the control frame signal input from radio layer 3 section 105 to radio layer 2 section 106. To do.

  The timing source unit 110 manages the CFN and outputs the CFN to the RNC control unit 104 at a predetermined timing.

  Next, the internal configuration of the FP unit 108 will be described with reference to FIG.

  The timing information extraction unit 201 extracts the CFN set in the Iur frame or the Iub frame input from the exchange unit 109 and outputs the extracted CFN to the timing control unit 202.

  The timing control unit 202 receives the CFN, which is the network function handover timing information input from the RNC control unit 104, and the CFN set in the Iur frame signal or the Iub frame signal input from the timing information extraction unit 201. Compare. Then, the timing control unit 202 executes SRNS Relocation for the FP control unit 203 when the comparison result indicates that the CFN of the timing for executing SRNS Relocation is a set Iur frame signal or Iub frame signal. To instruct.

  When the radio network controller 100 is an SRNC when it does not receive an instruction to execute SRNS Relocation from the timing controller 202, the FP controller 203 receives an Iur frame signal or an Iub frame input from the switching unit 109. When the wireless control apparatus 100 is a DRNC, the transfer destination of the Iur frame signal or the Iub frame signal input from the exchange unit 109 is output as the MDC unit 107 of its own to the exchange unit 109. The data is output to switching section 109 so as to be transferred from line I / F section 102 to another RNC as another RNC.

  Further, when receiving an instruction from the timing control unit 202 to execute SRNS Relocation, the FP control unit 203 receives an Iur frame signal or Iub frame input from the switching unit 109 according to the connection form after the SRNS Relocation is executed. Change the signal transfer destination. Specifically, the FP control unit 203 causes the Iur frame signal or the Iub frame signal in which the CFN after the network function handover timing is set, when the radio control apparatus 100 performs a network function handover and switches to a new SRNC. The transfer destination is changed from another RNC to its own MDC unit 107. Further, the FP control unit 203 transfers the Iur frame signal or the Iub frame signal in which the CFN after the network function handover timing is set when the radio network controller 100 performs the network function handover and switches from the SRNC to the new DRNC. The destination is changed from the own MDC unit 107 to another RNC that becomes the new RNC. Further, if the radio network controller 100 remains in DRNC even when the radio network controller 100 performs handover of the network function, the FP control unit 203 uses the Iur frame signal or Iub frame signal in which the CFN after the network function handover timing is set. Change the forwarding destination to another RNC that became the new SRNC.

  Next, regarding the operation of the mobile communication system to which the radio network controller 100 is applied, the radio network controller 100 is handed over from the state of FIG. 6 to the state of FIG. 7 using FIG. 3, FIG. 6, and FIG. I will explain. FIG. 3 is a sequence diagram showing the operation of the mobile communication system. 3, 6, and 7, SRNC 53 a, DRNC 53 b, DRNC 53 c, DRNC 61 a, and SRNC 61 b have the same configuration as in FIG. 1.

  First, the SRNC 53a determines to perform network function handover by executing SRNS Relocation.

  Next, the SRNC 53a that has decided to perform the network function handover transmits an allocation Required message to the SGSN 54 and notifies the start of the network function handover of the network function (step ST301).

  Next, the SGSN 54 determines whether the SRNS Relocation is an inter-SGSN SRNS Relocation that is an SRNS Relocation across SGSNs, and if it is an inter-SGSN SRNS Relocation, accommodates an RNC that is a new SRNC. A Forward Relocation Request message is transmitted to SGSN 62 (step ST302).

  Next, the SGSN 62 that has received the Forward Relocation Request message transmits a Relocation Request message to the DRNC 53c in order to set up an Iu bearer for data transfer with the DRNC 53c that becomes a new SRNC (step ST303).

  Next, the DRNC 53c that becomes the new SRNC determines the execution time of the SRNS Relocation in the RNC control unit 104, and transmits the Drift RNC Setup Request message including the notification of the execution time of the determined SRNS Relocation to the SRNC 53a that becomes the DRNC. (Step ST304). Here, in the Drift RNC Setup Request message, in order to set an Iur bearer for data transfer between the RNC serving as the new SRNC and the RNC serving as the DRNC, the SRNS Relocation execution time is notified. In the execution times CFN and DRNC, offset values (Frame Offset and Chip Offset) for calculating CFN from its own timing source are included.

  Next, the SRNC 53a that has received the Drift RNC Setup Request sets an Iur bearer and sets an RNS Relocation execution time in the RNC control unit 104, and then transmits a Drift RNC Setup Response message to the DRNC 53c that becomes the new SRNC ( Step ST305).

  Next, DRNC 53c that becomes the new SRNC transmits a Drift RNC Setup Request message to DRNC 53b (step ST306).

  Next, the DRNC 53b that has received the Drift RNC Setup Request sets the Iur bearer and determines the SRNS Relocation execution time in the RNC control unit 104, and then transmits the Drift RNC Setup Response message to the DRNC 53c that becomes the new SRNC ( Step ST307).

  Next, DRNC 53c serving as the new SRNC sets up an Iu bearer with SGSN 62, and then transmits a Relocation Request Acknowledge message indicating that preparation for SRNS Relocation is complete to SGSN 62 (step ST308).

  Next, the SGSN 62 that has received the Relocation Request Acknowledge message transmits a Forward Relocation Response message indicating that preparation for SRNS Relocation is complete to the SGSN 54 (step ST309).

  Next, SGSN 54 transmits a Relocation Command message permitting the start of SRNS Relocation to SRNC 53a in order to continue SRNS Relocation (step ST310).

  Next, the SRNC 53a starts to transfer the user data received from the SGSN 54 to the DRNC 53c that becomes a new SRNC in order to minimize the loss of user packets due to SRNS Relocation (step ST311).

  Next, SRNC 53a transmits a Relocation Commit message to DRNC 53c serving as the new SRNC in order to transfer the SRNS context to DRNC 53c serving as the new SRNC (step ST312). In this case, since the execution time of SRNS Relocation is specified by CFN, only the transfer of SRNS Context is performed in the Relocation Commit message.

  Next, when the SRNS Relocation execution time specified by the CFN is reached, the SRNC 53a, the DRNC 53b, and the DRNC 53c execute the SRNS Relocation.

  In the uplink direction, the FP unit 108 of the DRNC 61a transmits, to the SRNC 61b that has become the new SRNC, an Iub frame in which a CFN value after the SRNS Relocation execution time CFN is set among the Iub frames received from the NodeB 52c. The FP unit 108 of the RNC 53b transmits, to the SRNC 61b, an Iub frame in which a CFN value is set after the SRNS Relocation execution time CFN among the Iub frames received from the NodeB 52e. The FP unit 108 of the SRNC 61b transfers the Iub frame in which the CFN value after the execution time CFN of SRNS Relocation is set among the Iub frames received from the NodeB 52g to the MDC unit 107, and performs macro diversity combining processing to the SGSN 62. Send.

  In the downlink direction, the FP unit 108 of the DRNC 61a starts receiving data from the SRNC 61b and transmits the data to the NodeB 52c. The FP unit 108 of the RNC 53b starts receiving data from the SRNC 61b that has become the new SRNC, and transmits the data to the NodeB 52e. The FP unit 108 of the SRNC 61b starts receiving data from the SGSN 62, and the MDC unit 107 duplicates data for macro diversity combining at the MS 51, and transmits the data to the Node B 52g, the DRNC 61a, and the DRNC 53b.

  Next, after performing SRNS Relocation, DRNC 61a transmits Drift RNC Relocation Complete to SRNC 61b that has newly become SRNC (step ST313).

  In addition, after executing SRNS Relocation, DRNC 53b transmits Drift RNC Relocation Complete to SRNC 61b (step ST314). Regarding the execution of SRNS Relocation, the SRNC 61b can also recognize the time CFN. When the SRNC 61b automatically returns the Relocation Detect message after the time CFN is reached, the Drift RNC Relocation Complete message is sent. There is no need to send.

  Next, SRNC 61b transmits a Relocation Detect message indicating that SRNS Relocation has been executed to SGSN 62 (step ST315).

  Next, the SRNC 61b sets information such as the identifier of the new SRNC, the location area, and the identifier of the routing area in the UTRAN Mobility Information message and transmits it to the MS 51 (step ST316).

  Next, when receiving the UTRAN Mobility Information message, MS 51 transmits a UTRAN Mobility Information Confirm message to SRNC 61b (step ST317).

  Next, the SRNC 61b transmits a Relocation Complete message to the SGSN 62, and notifies that SRNS Relocation has been normally completed (step ST318).

  Next, when SRNS Relocation is Inter-SGSN SRNS Relocation, SGSN 62 notifies the previous SGSN 54 that SRNS Relocation has been normally completed by a Forward Relocation Complete message (step ST319).

  Next, SGSN 54 that has received the Forward Relocation Complete message transmits a Forward Relocation Complete Acknowledge message to SGSN 62 (step ST320).

  Next, after receiving the Relocation Complete message, SGSN 62 transmits an Update PDP Context Request message to GGSN 56 (step ST321).

  Next, GGSN 56 which has received the Update PDP Context Request message transmits an Update PDP Context Response message to SGSN 62 (step ST322). Thereby, the path | route between GGSN56 and SGSN62 is changed into the new SGSN62 side.

  Next, after receiving the Forward Relocation Complete message, SGSN 54 transmits an Iu Release Command message to DRNC 61a (step ST323).

  Next, DRNC 61a that has received the Iu Release Command message transmits an Iu Release Command message to SGSN 54 (step ST324). As a result, the communication connection between the SGSN 54 and the DRNC 61a is released.

  Next, when the routing area information notified by the UTRAN Mobility Information is different from the previous information in Step ST316 and Step ST317, the MS 51 performs Routing Area Update with the new SGSN 62.

  Thus, according to the mobile communication system and radio network control method of the present embodiment, network function handover is simultaneously performed in all RNCs using CFN, so that packet loss can be prevented and communication quality can be prevented. Can be prevented. Also, according to the mobile communication system of the present embodiment, the timing of network function handover is controlled using a signal for controlling timing between the radio control apparatus having a function of performing radio channel control and the mobile terminal. Therefore, a new signal for controlling the timing of network function handover is unnecessary, and the network function handover process can be simplified.

  INDUSTRIAL APPLICABILITY The mobile communication system and the radio network control method according to the present invention can prevent packet loss and prevent the deterioration of communication quality, and are useful for controlling network function handover.

The block diagram which shows the structure of the radio | wireless control apparatus which concerns on embodiment of this invention The block diagram which shows the structure of FP part which concerns on embodiment of this invention The sequence diagram which shows operation | movement of the mobile communication system which concerns on embodiment of this invention. Schematic diagram showing network configuration Schematic diagram showing network configuration Schematic diagram showing network configuration Schematic diagram showing network configuration

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Radio control apparatus 104 RNC control part 105 Radio layer 3 part 106 Radio layer 2 part 107 MDC part 108 FP part 109 Exchange part 110 Timing source part

Claims (9)

  In the host station apparatus of the radio control apparatus, the network function handover is a process of switching the radio control apparatus to be a specific station that collectively processes data from base station apparatuses in the control area of all radio control apparatuses. If permitted, based on a timing control signal for controlling the timing of the network function handover, the radio control device simultaneously performs the network function handover and the radio control device switches the specific station. A wireless network control method.   The radio network control method according to claim 1, wherein a signal for controlling timing between the radio control apparatus as the specific station and a terminal apparatus is used as the timing control signal. A wireless control device that performs network function handover that is a process of switching specific stations that collectively process data in the control area of each station and serves as a serving wireless network control device that is the specific station,
Timing determining means for determining the timing for performing the network function handover based on a timing control signal for controlling the timing of the network function handover;
Notification means for notifying other stations of the timing determined by the timing determination means;
The network function handover is performed at the timing determined by the timing determination means, thereby stopping the transfer of data in the control area of the own station to the other station and transferring the data in the control area of the other station from the other station. Data transfer control means for switching to be performed,
Data processing means for processing the data in the control area of the local station and the data in the control area of the other station transferred from the other station after becoming the specific station;
A wireless control device comprising:   The radio control apparatus according to claim 3, wherein the timing determination unit uses a signal for controlling timing between the specific station and a terminal apparatus as the timing control signal. Radio switching to a drift radio network controller that performs network function handover, which is a process of switching specific stations that collectively process control area data of each station, and serves as a serving radio network controller to transfer data from the specific station to the specific station A control device,
Data processing means for processing the data of the control area of the local station and the data of the control area of the other station transferred from the other station when it is the specific station;
An acquisition means for newly acquiring a timing control signal for controlling the timing of the network function handover from the other station as the specific station;
The network function handover is performed simultaneously with the other station based on the timing control signal acquired by the acquisition means, thereby stopping transfer of data in the control area of the other station from the other station to the own station. Data transfer control means for switching so that data in the control area of the station is newly transferred to the other station as the specific station;
A wireless control device comprising: A drift radio network control device that transfers data to a specific station that is a change destination every time the specific station is changed by performing a network function handover that is a process of switching specific stations that collectively process control area data of each station. A wireless control device,
An acquisition means for acquiring a timing control signal for controlling the timing of the network function handover from the other station that becomes a new specific station by performing the network function handover;
Data transfer for switching so that the data in the control area of the local station is transferred to the specific station to be changed by handing over the network function simultaneously with the other station based on the timing control signal acquired by the acquiring means Control means;
A wireless control device comprising:   The radio control apparatus according to claim 5, wherein the acquisition unit acquires the timing control signal using a signal for controlling timing between the specific station and a terminal apparatus. . A mobile terminal,
A base station device that transmits and receives data to and from the mobile terminal;
A plurality of radio network controllers that perform network function handover that is a process of switching specific stations that collectively process data from the base station apparatus in the control area of all other stations;
An upper station apparatus that determines whether or not to permit the network function handover to the radio control apparatus that requests permission to become the specific station by the network function handover;
A mobile communication system comprising:
When the network function handover is permitted in the upper station apparatus, the network function handover is simultaneously performed in all the radio control apparatuses based on a timing control signal for controlling the timing of the network function handover. A mobile communication system.   9. The mobile communication system according to claim 8, wherein the radio control device uses a signal for controlling timing between the radio control device as the specific station and a terminal device as the timing control signal. .

Images