KR20020046625A - Srnc reallocation method upon hand-off in imt-2000 system - Google Patents

Abstract

PURPOSE: A method for relocating an SRNC(Serving Radio Network Controller) in a handoff in an IMT-2000 system is provided to optimize path resources from a terminal to an MSC(Mobile Switching Center) in a handoff. CONSTITUTION: An SRNC transmits a soft handoff required message, including the ID of a DRNC(Drift Radio Network Controller), to an MSC(S11). After confirming the DRNC through the "soft handoff required" message, the MSC transmits a handoff request signal for the allocation of a radio access bearer to the DRNC(S12). In response to the handoff request signal, the DRNC sets up a transmission bearer with the MSC using a transport layer address and transmits a handoff request acknowledgement signal to the MSC(S13). If the MSC transmits a handoff command to the SRNC(S14), the SRNC transmits a handoff commenced message to the MSC. At the same time, the SRNC transmits an SRNC relocation commit message to the DRNC. Then the SRNC stops a data transmission operation for the forward and reverse paths with the MSC(S15). Receiving the SRNC relocation commit message, the DRNC sets up a radio transmission link with a relevant terminal and transfers itself as a serving DRC. Then the DRNC transmits a handoff complete message to the MSC(S16). The MSC switches the forward and reverse paths to the present SRNC and transmits a clear command to the previous SRNC(S17).

Description

SRNC reassignment method for handoff in IMT-2000 system {SRNC REALLOCATION METHOD UPON HAND-OFF IN IMT-2000 SYSTEM}

The present invention relates to an International Mobile Telecommunication (IMT). 2000 Serving Radio Network Controller (SRNC) during handoff in an interworking system between an asynchronous control station and a synchronous switching center. The present invention relates to a reassignment method, and more particularly, a hand in an IMT-2000 system that optimizes a path between a control station and an exchange station when performing a soft handoff or a hard handoff. SRNC reassignment method when off.

As is well known, the IMT-2000 service method provides an IMT-2000 synchronous method (3GPP-2: 3rd Generation Partnership Project-2) service and an IMT-2000 asynchronous method (3GPP: 3rd Generation Partnership Project) service. It is divided in a manner. At this time, there is a case where an IMT-2000 asynchronous (3GPP) service is to be provided in a region that provides a service using the IMT-2000 synchronous (3GPP-2) system. In this case, if the IMT-2000 asynchronous control station and the IMT-2000 synchronous switching station can be interworked, there is no need to construct a separate IMT-2000 asynchronous switching station. This can further increase the efficiency of the IMT-2000 asynchronous control station. Thus, there is a need for a system capable of performing services in a system in which an IMT-2000 asynchronous (3GPP) control station and a synchronous (3GPP-2) switching station are interworked.

However, in a system in which a conventional IMT-2000 asynchronous (3GPP) control station and a synchronous (3GPP-2) switching station are interworked, there is no method for reallocating an SRNC when a hard handoff or a soft handoff occurs. The path resources connected from the base station to the exchange through the base station and the control station are not only inefficiently operated, but also the efficiency of the entire system is lowered because the path resources of the IMT-2000 system are not optimized.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to reallocate SRNC during handoff in an IMT-2000 system for optimizing a pass resource from a terminal to an exchange during handoff. To provide a way.

In order to achieve the above object, SRNC reallocation method in the handoff in the IMT-2000 system of the present invention is an asynchronous serving control station in charge of call processing of a terminal before performing soft handoff, and after performing soft handoff. SRNC reassignment method in handoff in an IMT-2000 system comprising an asynchronous target control station in charge of call processing of a terminal and a synchronous switching station performing call processing in association with the serving control station and the target control station. To

An eleventh step of, when the soft handoff occurs in the terminal, the serving control station transmits a soft handoff request message including an ID of a target control station to the switching station;

A twelfth step, wherein the switching center requests radio access bearer allocation to the target control station;

A thirteenth step, wherein the target control station establishes a transmission bearer between the switching station and itself and informs the switching station of the response to the radio access bearer allocation;

The fourteenth step, wherein the switching center sends a soft handoff progress instruction to the serving control station;

Sending a soft handoff initiation message to the switching center at the same time as the serving control station transmits an SRNC reassignment request message to the target controlling station, and then stops the data transmission operation on the forward / reverse path with the switching station; Step 15;

A sixteenth step of the target control station establishing a wireless transmission link with the terminal to switch to a serving control station, and then sending an SRNC reallocation success message to the switching station;

A seventeenth step of the switching station switching the forward / reverse path to the target control station switched to the serving control station and then transmitting a clear command to the previous serving control station; And

It is characterized in that it comprises an eighteenth step of releasing all call processing paths used by the serving control station before performing the soft handoff and notifying the switching station of the result.

In addition, the SRNC reallocation method during handoff in the IMT-2000 system of the present invention is an asynchronous serving control station in charge of call processing of a terminal before performing a hard handoff, and a call processing of the terminal after performing a hard handoff. In the SRNC reallocation method in the handoff in the IMT-2000 system comprising an asynchronous target control station and a synchronous switching station that performs call processing in conjunction with the serving control station and the target control station,

A twenty-first step of, when the hard handoff occurs in the terminal, the serving control station transmits a hard handoff request message including an ID of a target control station to the switching station;

A twenty-second step of the switch station requesting a radio access bearer assignment to the target control station;

A twenty-third step of the target control station notifying the switching station of the radio access bearer allocation after performing the transmission bearer setting with the switching station and itself and the transmission bearer setting with the base station;

A twenty-fourth step, wherein the switching center sends a hard handoff progress instruction to the serving control station;

A twenty-fifth step of requesting, by the serving control station, to perform a hard handoff to a terminal after receiving a hard handoff progress command from the switching station;

A twenty sixth step of the target control station transmitting a hard handoff initiation message to the switching station when the terminal performs forward / reverse valid data reception procedure with the terminal;

A step 27 of the target control station establishing a wireless transmission link with the terminal to switch to a serving control station, and then transmitting an SRNC reallocation success message to the switching station;

A twenty-eighth step, wherein the switching center sends a clear command to the serving control station before hard handoff; And

And a twenty-ninth step of releasing all call processing paths used by the serving control station before performing the hard handoff and notifying the switching station of the result.

1 is a functional block diagram illustrating a configuration of an SRNC reallocating apparatus at handoff in an IMT-2000 system according to an embodiment of the present invention;

2 is a flowchart illustrating an SRNC reassignment method when a soft handoff occurs among SRNC reassignment methods in an IMT-2000 system according to an embodiment of the present invention;

3 is a signal flowchart illustrating a SRNC reallocation method during soft handoff in the IMT-2000 system according to FIG. 2;

4A and 4B are reference diagrams for explaining a SRNC reassignment method when handoff in an IMT-2000 system according to FIG. 2;

5 is an operation flowchart showing an SRNC reallocation method when a hard handoff occurs among SRNC reallocation methods in an IMT-2000 system according to this embodiment of the present invention;

FIG. 6 is a signal flowchart illustrating a SRNC reallocation method during hard handoff in the IMT-2000 system according to FIG. 5.

<Explanation of symbols for the main parts of the drawings>

100: serving control station 200: target control station

300: exchange office

Hereinafter, a SRNC reassignment method during handoff in an IMT-2000 system according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a functional block diagram of an SRNC reallocation device during handoff in an IMT-2000 system according to an embodiment of the present invention, and the SRNC reallocation during handoff in an IMT-2000 system according to an embodiment of the present invention. The apparatus consists of a Serving Radio Network Controller (SRNC) 100, a Drift Radio Network Controller (DRNC) 200, and a Mobile Switching Conter (MSC) 300.

The serving control station 100 is an asynchronous control station before a soft or hard handoff occurs in the terminal 1. The serving control station 100 performs a call processing of the terminal 1 before performing a soft or hard handoff. If a soft or hard handoff occurs, SRNC reassignment operation is performed accordingly.

In addition, the target control station 200 is an asynchronous control station that performs call processing of the terminal 1 when a soft or hard handoff occurs in the terminal 1, When a call processing path of the terminal 1 is designated toward itself due to a soft or hard handoff, it plays a role of performing call processing of the terminal 1 through interworking with the switching center 300.

On the other hand, the switching center 300 is a synchronous system for performing call processing in conjunction with the asynchronous serving control station 100 and the target control station 200.

Next, an SRNC reassignment method during handoff in an IMT-2000 system according to an embodiment of the present invention using the SRNC reallocation device during handoff in an IMT-2000 system having the above configuration will be described. .

First, referring to FIG. 2, FIG. 3, FIG. 4A, and FIG. 4B of the SRNC reallocation method when a soft handoff occurs among SRNC reallocation methods during handoff in an IMT-2000 system according to an embodiment of the present invention. This will be described.

First, after performing a soft handoff to add a radio link to an active set, the terminal 1 is connected to both the serving control station 100 and the target control station 200, as shown in FIG. 4A. Has a wireless path for In this state, when the path provided from the serving control station 100 to the terminal 1 is deleted, and the serving control station 100 and the target control station 200 are connected to the same switching center 300, the The serving control station 100 determines whether to perform the reassignment procedure. In this case, the basis for the determination of whether to perform the reassignment procedure is determined using the switching center domain ID in the radio link setup message transmitted from the target control station 200 to the serving control station 100 in the path addition process. Accordingly, the serving control station 100 performs the SRNC reassignment operation according to the above determination result. In the following, it is assumed that the serving control station 100 determines to perform the SRNC reassignment operation.

If so, the serving control station 100 first transmits a soft handoff request message (Handoff Required) including the ID of the target control station 200 to the switching center 300, as shown in FIG. (S11).

Then, after receiving the soft handoff request message (Handoff Required) from the serving control station 100, the switching center 300 confirms the target control station 200 through the message. Thereafter, the switching center 300 transmits a radio access bearer allocation request signal (Handoff Request) to the identified target control station 300 (S12).

Then, the target control station 200 establishes a transport bearer between the switching center 200 and itself using a transport layer address, and as shown in FIG. 3, the switching center 200. In step S13, a response signal (Handoff Request Ack) for radio access bearer allocation is transmitted.

Subsequently, the switching center 300 receives a response signal (Handoff Request Ack) for radio access bearer allocation from the target control station 200, and causes the serving control station 100 to perform SRNC reallocation. In order to transmit the soft handoff progress command (Handoff Command) (S14).

Then, the serving control station 100 transmits a soft handoff initiation message (Handoff Commenced) to the switching center 300 and simultaneously transmits an SRNC reassignment request message (RELOCATION COMMIT) to the target control station 200. . Then, the serving control station 100 stops the data transmission operation for the forward and reverse paths with the switching center 300 (S15).

Then, the target control station 200 receives the SRNC reassignment request message (RELOCATION COMMIT) from the serving control station 100, and then establishes a radio transmission link with the terminal 1 to the serving control station itself. Switch. Thereafter, the target control station 200 transmits an SRNC reallocation success message (Handoff Complete) to the switching center 300 as shown in FIG. 3 (S16).

Subsequently, the switching center 300 switches the forward and reverse paths to the target control station 200 switched to the serving control station, and then sends a clear command to the previous serving control station (as shown in FIG. 3). 100) (S17).

Then, before performing the soft handoff, the serving control station 100 releases all call processing paths used by the serving control station 100 as shown in FIG. 3, and then sends a message (Clear Complete) regarding the result to the switching center 300. Notify (S18). Here, all call processing paths of the serving control station 100 before the soft handoff means a transmission bearer between itself and the switching center 300, a transmission bearer between itself and the base station, and a transmission bearer between itself and the target control station.

Therefore, when the SRNC allocation operation as described above is completed, the call processing path of the terminal 1 is optimized as shown in FIG. 4B.

Meanwhile, the SRNC reassignment method when a hard handoff occurs among SRNC reallocation methods during handoff in the IMT-2000 system according to an embodiment of the present invention will be described with reference to FIGS. 5 and 6.

First, when a hard handoff occurs in the terminal 1 and the serving control station 100 determines that SRNC reallocation due to hard handoff is necessary, the serving control station 100 is shown in FIG. 6. As described above, the hard handoff request message (Handoff Required) including the ID of the target control station 200 is transmitted to the switching center 300 (S21).

Then, after receiving the hard handoff request message (Handoff Required) from the serving control station 100, the switching center 300 transmits a radio access bearer allocation request signal (Handoff Request) to the target control station 200. (S22).

Subsequently, the target control station 200 receives a radio access bearer allocation request signal (Handoff Request) from the switching center 300, sets up a transmission bearer between the switching center 300 and the terminal 1, and the terminal 1 Performs a transmission bearer setup operation between the base station and itself connected to the base station. Thereafter, the target control station 200 transmits a response signal (Handoff Request Ack) for radio access bearer allocation to the switching center 300 as shown in FIG. 6 (S23).

Then, the switching center 300 transmits a hard handoff progress command (Handoff Command) to the serving control station 100, as shown in Figure 6 (S24).

Subsequently, the serving control station 100 receives a hard handoff progress command (Handoff Command) from the switching center 300 and requests the terminal 1 to perform a hard handoff (S25). Then, the terminal 1 performs a hard handover and at the same time performs a valid data reception procedure through the target control station 200 in the forward and reverse directions.

Subsequently, when the terminal 1 performs a forward / reverse valid data reception procedure with the terminal 1, the target control station 200 receives a hard handoff commencement message (Handoff Commenced) to the switching center 300 as shown in FIG. ) Is transmitted (S26).

The target control station 200 then establishes a wireless transmission link with the terminal 1 and switches itself to the serving control station. Thereafter, the target control station 200 transmits an SRNC reallocation success message (Handoff Complete) to the switching center 300 (S27).

Subsequently, the switching center 300 transmits a clear command to the serving control station 100 before hard handoff as shown in FIG. 6 (S28).

Then, the serving control station 100 before performing the hard handoff releases all the call processing paths used by the serving control station 100 and transmits a result message (Clear Complete) to the switching center 300 (S29). Here, all call processing paths of the serving control station 100 before performing the hard handoff means a transmission bearer between itself and the switching center 300 and a transmission bearer between itself and the base station.

As described above, according to the SRNC reallocation method for handoff in the IMT-2000 system according to the present invention, when a hard handoff or a soft handoff occurs in the terminal, the SRNC is reassigned so as to start the base station, Not only does it optimize the path resources connected to the switch via the control station, it also has the effect of improving the efficiency of the entire system.

Claims (2)

Asynchronous serving control station in charge of call processing of the terminal before performing soft handoff, asynchronous target control station in charge of call processing of the terminal after performing soft handoff, and interworking with the serving control station and target control station. In the SRNC reallocation method at the time of handoff in an IMT-2000 system composed of a synchronous switching center which proceeds with call processing, An eleventh step of, when the soft handoff occurs in the terminal, the serving control station transmits a soft handoff request message including an ID of a target control station to the switching station; A twelfth step, wherein the switching center requests radio access bearer allocation to the target control station; A thirteenth step, wherein the target control station establishes a transmission bearer between the switching station and itself and informs the switching station of the response to the radio access bearer allocation; The fourteenth step, wherein the switching center sends a soft handoff progress instruction to the serving control station; Sending a soft handoff initiation message to the switching center at the same time as the serving control station transmits an SRNC reassignment request message to the target controlling station, and then stops the data transmission operation on the forward / reverse path with the switching station; Step 15; A sixteenth step of the target control station establishing a wireless transmission link with the terminal to switch to a serving control station, and then sending an SRNC reallocation success message to the switching station; A seventeenth step of the switching station switching the forward / reverse path to the target control station switched to the serving control station and then transmitting a clear command to the previous serving control station; And SRNC reallocation during handoff in the IMT-2000 system, characterized in that the serving control station before performing the soft handoff releases all call processing paths used by the serving control station and informs the switching center of the result. Way. Asynchronous serving control station in charge of call processing of the terminal before performing hard handoff, Asynchronous target control station in charge of call processing of the terminal after performing hard handoff, and interworking with the serving control station and target control station. In the SRNC reallocation method at the time of handoff in an IMT-2000 system composed of a synchronous switching center which proceeds with call processing, A twenty-first step of, when the hard handoff occurs in the terminal, the serving control station transmits a hard handoff request message including an ID of a target control station to the switching station; A twenty-second step of the switch station requesting a radio access bearer assignment to the target control station; A twenty-third step of the target control station notifying the switching station of the radio access bearer allocation after performing the transmission bearer setting with the switching station and itself and the transmission bearer setting with the base station; A twenty-fourth step, wherein the switching center sends a hard handoff progress instruction to the serving control station; A twenty-fifth step of requesting, by the serving control station, to perform a hard handoff to a terminal after receiving a hard handoff progress command from the switching station; A twenty sixth step of the target control station transmitting a hard handoff initiation message to the switching station when the terminal performs forward / reverse valid data reception procedure with the terminal; A step 27 of the target control station establishing a wireless transmission link with the terminal to switch to a serving control station, and then transmitting an SRNC reallocation success message to the switching station; A twenty-eighth step, wherein the switching center sends a clear command to the serving control station before hard handoff; And The SRNC re-executes the handoff in the IMT-2000 system, wherein the serving control station before performing the hard handoff releases all call processing paths used by the serving control station and informs the switching station of the result. Assignment method.