KR100214130B1 - Method for controlling hand-off in the midst of ring back tone among mobile service switching centers in a serving mobile service switching center - Google Patents

Abstract

According to the present invention, a mobile subscriber station (hereinafter referred to as an exchange) attempts to make a call and moves to an area controlled by another mobile communication switch while receiving a ring back tone (hereinafter referred to as RBT). The present invention relates to a switching period handoff control method during a ringback tone in a serving mobile communication exchange suitable for continuously maintaining a call path for an ongoing call. In the related art, a handoff is performed only when a mobile subscriber is in a busy state. Although there is a drawback that the call quality is degraded or the call is dropped for the current call, that is, the call of the subscriber receiving the RBT by providing the service, in the present invention, the calling mobile subscriber at the mobile communication exchange receives another RBT while receiving the RBT. Move to the area controlled by the By preventing the disconnection of ongoing calls and providing better call quality service, the above-mentioned drawbacks can be ameliorated.

Description

Switching period handoff control method during ringback tone in serving mobile communication exchange

In the present invention, when a mobile subscriber exchanges a ring back tone (hereinafter referred to as RBT) in a mobile communication switch (hereinafter, referred to as an exchange) and receives a ring back tone, the present invention currently moves to an area controlled by another mobile communication switch. The present invention relates to a switching period handoff control method during ringback tones in a serving mobile communication exchange that maintains a call path for an ongoing call.

In the related art, since the handoff service is provided only when the mobile subscriber is in a busy state, the call quality is degraded or the call is dropped for the current call, that is, the call of the subscriber receiving the RBT.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art, and provides a handoff service when an originating mobile subscriber moves to an area controlled by another exchange while receiving an RBT at an exchange, thereby preventing a disconnection of an ongoing call. It is aimed at preventing and providing better call quality services.

In order to achieve the above object, the present invention provides a serving exchange for controlling a handoff that has occurred (abbreviated as mobile communication exchange), a target exchange for handoff from a serving exchange and finally processing a call, and a base station in a serving exchange. The base station controller matching unit responsible for matching with the controller and operation management for the relay line, the control of mobile call processing and mobility management, the call processing control unit controlling the base station controller matching unit, and the handoff control. A handoff control unit controlling each base station controller matching unit, another exchange matching unit matching the connection with other stations under the control of the handoff control unit and the call processing control unit, and connecting the subscribers through a switching operation. The switch connection to the connection and the mobile subscriber belonging to the target exchange When a call is normally received by the called party, the handoff control unit of the serving exchange starts an outgoing call setup, and the serving exchange connects the RBT to the calling party and then at the serving mobile communication exchange waiting for the called party to respond in the RBT state. In the method of controlling a switching period during the ringback tone of the call, the serving base station controller sends a handoff required message to the serving exchange side when the calling subscriber moves to an area controlled by another exchange during the RBT. The handoff control unit of the serving exchange receiving the inquiry message determines the handoff between the exchanges by analyzing the target cell information in the message and determines the target exchanger: selecting one available relay line from among the handoff relay lines connected to the target exchanger. Seize, relay to the target exchange Receiving a facility command result message by sending a facility commands message including information and target cell information: a first determination step of determining whether handoff is possible by referring to a result message for the facility command at the serving exchange; : Determination in the first determination step, if the handoff is possible to proceed with the handoff: A second determination step of determining whether the handoff is successful by referring to the handoff result message in the serving exchange: If the handoff is successful, the serving exchange releases the radio resources associated with the call to the serving base station controller: connecting and transmitting a handoff path by transmitting and receiving an intersystem response message between the serving exchange and the target exchange. Serving mobile communication bridge, characterized in that consisting of steps Provided is a method of controlling handoff period during ringback tone in ventilation.

1 is a block diagram of a serving mobile communication exchange inside which can accommodate an inter-switch handoff control method according to the present invention.

2A to 2C are flowcharts for explaining a switching period handoff control method during ringback tones in a handoff control unit in a serving exchange according to the present invention.

* Explanation of symbols for main parts of the drawings

100: call processing control unit 102: handoff control unit

104: base station controller matching unit 106: other switch matching unit

108: switch connection

The above and other objects and various advantages of the present invention will become more apparent from the preferred embodiments of the invention described below with reference to the accompanying drawings by those skilled in the art.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a preferred embodiment of the present invention.

In reference to FIG. 1, FIG. 1 shows a system internal configuration diagram for switching period handoff control during RBT in a serving mobile communication exchange.

In the case of handoff only in two exchange areas, the first exchange is divided into the anchor exchange generated first and the target exchange receiving the exchange.

The base station controller matching unit 104 is responsible for matching with the base station controller and operation management for the relay line, and distributes the received message to the call processing control unit 102 or the handoff control unit 104 according to the type.

The call processing control unit 100 is responsible for the overall control of the outgoing mobile call processing. And, the call processing control unit 100 is connected to the other exchange matching unit 106 in relation to the call to control the call received and transmitted from another station, the base station controller matching unit 104 receives the call of the own station or external It functions to export to, and is connected to the switch connection unit 108 to control the switching connection to handle the connection between subscribers.

The handoff control unit 102 is responsible for the control of the handoff and the switching connection control for the handoff for the new call path through the switch connection unit 105.

The other exchange matching unit 106 transmits and receives a matching message between the counterpart exchange and the station through the No. 7 signal link.

The switch connection unit 108 performs a switching connection operation to the base station controller matching unit 104 or another exchange matching unit 106 under the control of the handoff control unit 102 and the call processing control unit 100.

Fig. 2 shows a process flow for the exchange period handoff control during RBT at the handoff control unit in the serving exchange.

If the mobile subscriber attempts to make an outgoing call and the call is normally received by the called party, the handoff control unit 102 of the serving exchange starts up the outgoing call setup (step 200).

The serving exchange connects the RBT to the calling subscriber (step 202).

Wait for the called party to respond in the RBT state (step 204).

If the originating subscriber moves to an area controlled by another exchange during the RBT, the serving base station controller sends a Handoff Required message to the serving exchange side (step 206).

The handoff control unit 102 of the serving exchange analyzes the target cell information in the message, determines that it is a handoff between exchanges, and determines the target exchange (step 208).

In order to establish a call, one of the handoff relay lines connected to the target exchange occupies one available relay line (step 210).

A Facilities Directive Invoke message including relay line information and target cell information is sent to the target exchange (step 212).

Wait for the result for the facility command (step 214).

The target exchange receiving the facility command message makes a handoff request to the target base station controller to receive the authentication signal.

The serving exchange receives a Results (Facilities Directive Retrun) message from the target exchange (step 216).

The handoff control unit 102 of the serving exchange determines whether handoff is possible by referring to the result message for the facility command (step 218).

If it is determined in step 218 that the handoff is impossible, a handoff reject message including a cause of failure is sent to the serving base station controller (step 220).

The relay line for handoff with the target exchange occupied in step 210 is released (step 222).

Transition to RBT state and end handoff control (step 224).

In step 218, if a handoff is possible, a handoff command message is sent to the serving base station controller (step 226).

Wait in the handoff ongoing state (step 228).

The serving exchange receives a Handoff Commenced from the serving base station controller that the terminal is currently handing off (step 230).

The handoff switch for the RBT connection and the handoff call path to the target exchange is then secured via the switch connection 108 (step 232).

Wait for the result of performing the handoff (step 234).

The mobile terminal completes the handoff and sends a handoff complete message to the target base station controller while waiting for the handoff performance result at the serving exchange.

The target base station controller receiving the handoff complete message informs the target exchange that the terminal has completed the handoff.

The serving exchange receives a Mobile On Channel Invoke message from the target exchange (step 236).

The handoff control unit 102 of the serving exchange determines whether the handoff is successful by referring to the handoff result message (step 238).

If it is determined in step 238 that the handoff fails, the relay line for handoff with the target exchange occupied in step 210 is released (step 240).

Release the handoff switch obtained in step 232 for the handoff call path (step 242).

Transition to the RBT state and end the handoff control (step 244).

As a result of the determination in step 238, if the handoff is successful, the RBT is connected by connecting the handoff switch secured to the target exchanger (step 246).

Release to the RBT connection that was connected between the serving exchange and the serving base station controller before the handoff occurred (step 248).

The serving exchange sends a Clear Request message of radio resources associated with the call to the serving base station controller (step 250).

Wait for a release result to be received from the serving base station controller (step 252).

A radio resource release result (Clear Compleye) message is received from the serving base station controller (step 254).

The serving exchange registers handoff related information for that mobile subscriber (step 256).

Then, the called party waits for a response (step 258).

The call processing control unit 100 receives a notification that the called party has responded (step 260).

An Inter System Answer Invoke message is sent to the target exchange (step 262, step 264).

Receive an Inter System Answer Return Result message from the target exchange (step 266).

The RBT is disconnected to the target exchange via the switch connection 108 for the call route and the handoff call route is connected (step 268).

The exchange period handoff control process during the RBT at the serving exchange is terminated, and the next event is waited for in the handoff busy state (step 270).

As described above, the present invention provides a handoff service when an outgoing mobile subscriber moves to an area controlled by another exchange in a state where the RBT receives an RBT at the mobile communication exchange, thereby preventing an ongoing call disconnection and providing better call quality service. To provide.

The principles of the invention have been described above in connection with specific devices, which are described by way of example only, and are not limited to the spirit of the invention as described in the appended claims.

Claims (6)

A serving exchange that controls the generated handoff, a target exchange receiving a handoff command from the serving exchange, and a base station controller that is responsible for matching the base station controller at the serving exchange and managing operations for the relay line. And a call processing controller 100 for controlling the mobile call processing and mobility management, and controlling the base station controller matching units 104 and 106, and a handoff control. A handoff control unit 102 controlling the base station controller matching units 104 and 106, another exchange matching unit matching the connection with other stations under the control of the handoff control unit 102 and the call processing control unit 100, and switching A mobile subscriber belonging to the target exchange, which is composed of a switch connection unit 108 that connects subscribers through an operation and connects a call path, When the call is received and the called party is normally received, the handoff control unit 102 of the serving exchange starts an outgoing call setup, and the serving exchange connects the RBT to the calling party, and the called party answers in the RBT state. In a method of controlling an exchange period handoff during a ringback tone in a serving mobile communication exchange waiting for the serving, the serving base station controller issues a handoff required message when the calling subscriber moves to an area controlled by another exchange during RBT. Sending a message to the serving exchange side and receiving the handoff capable query message, the handoff controller 102 of the serving exchange analyzing the target cell information in the message to determine handoff between the exchanges and determining a target exchange; Occupying one of the available relay lines among the handoff relay lines connected to the target switch, and receiving a facility command result message including a facility command message including relay line information and target cell information to the target switch; ; A first determination step of determining, by the serving exchange, whether a handoff is possible with reference to a result message for a facility command; Determining in the first determination step and, if the handoff is possible, proceeding with the handoff; A second determination step of determining, by the serving exchange, whether the handoff is successful by referring to a handoff result message; As a result of the determination in the second determination step, if the handoff is successful, the serving exchange releases the radio resource associated with the call to the serving base station controller; And transmitting and receiving an inter-system response message between the serving exchange and the target exchange to connect a handoff call path. 2. The method of claim 1, further comprising: determining, by the first determining step, a handoff reject message including a cause of failure to the serving base station controller when the handoff is impossible; Releasing a relay line for handoff with the target exchange; Transitioning to the RBT state and ending the handoff control. The method of claim 1, wherein the step of determining in the first determination step and releasing radio resources associated with the call when handoff is possible comprises: performing a handoff request to the serving base station controller performing the handoff (Handoff Command) Receiving a notification that a handoff is in progress by sending a message (Handoff Commenced); The handoff switch for the RBT connection path and the handoff call path to the target exchange through the switch connection 108 is obtained, and the serving exchange receives a Mobile On Channel Invoke message from the target exchange. And a switching period handoff control method during ringback tones in the serving mobile communication exchange. 2. The method of claim 1, wherein if the handoff fails as a result of the determination in the second determination step, releasing the relay line for handoff with the target exchanger: releasing the secured handoff switch. And a step of transitioning to an RBT state and ending the handoff control. The method of claim 1, wherein in the second determination step, when the handoff is successful, connecting the RBT by connecting the handoff switch secured to the target exchanger: serving with the serving exchange before the handoff occurs. Releasing the RBT connection path that was connected between the base station controllers; The serving exchange sending a Clear Request message of a radio resource associated with the call to the serving base station controller to receive a Clear Resource Complete message; And the serving exchange further comprises registering handoff related information for the corresponding mobile subscriber. 2. The method of claim 1, wherein connecting the handoff communication path by transmitting and receiving an intersystem response message between the serving exchange and the target exchange comprises: transmitting and receiving an intersystem response message between the serving exchange and the target exchange. Step of connecting the call: Receiving a notification from the call processing control unit that the called party answered: Sending an Inter System Answer Invoke message to the target exchange and receiving an Inter System Answer Return Result message. ; Disconnecting the RBT to the target exchange through the switch connection unit 108 and connecting the handoff communication path for connection to the call: ending the exchange period handoff control process during the RBT at the serving exchange, and performing a handoff busy state And waiting for the next event in the switching back-end handoff control method of the ring back tone in the serving mobile communication corrector.