KR100551800B1 - Method for processing call for stable voice channel - Google Patents

Abstract

The present invention relates to a call processing method for forming a voice channel in a communication system including one or more terminals, the method comprising: forming a voice channel after transmitting and receiving a Called Subscriber Answer (CSA) packet between communication partners of the communication system; CSA ACK (Called Subscriber), which is the last signaling packet of a call processing procedure, is first transmitted / received between the communication partners after the formation of a voice channel. Answer Acknowledgment).

CSA, CSA ACK

Description

Call processing method for stable voice channel formation {METHOD FOR PROCESSING CALL FOR STABLE VOICE CHANNEL}             

1 is a view showing a call processing procedure according to the prior art,

2 is a block diagram of a general mobile communication system to which the present invention can be applied;

3 is a message flow diagram illustrating a call processing procedure according to the present invention;

4 is a diagram showing the structure of a voice packet according to an embodiment of the present invention;

5 is a control flowchart illustrating a call processing procedure at a CSA ACK packet originating party;

6 is a control flowchart showing a call processing procedure at a CSA ACK packet receiver.

The present invention relates to a call processing procedure in a communication system, and more particularly, to a call processing procedure for forming a voice channel in a communication system.

In general, a call processing procedure is performed in order to make a call by connecting a call in a communication system. In the call processing process, a voice channel is formed after a Called Subscriber Answer (CSA) packet and a Called Subscriber Answer Acknowledgement (CSA ACK) packet are exchanged between the UE / system and the system / terminal. The call processing procedure for exchanging the CSA packet and the CSA ACK packet is illustrated in FIG. 1.

1 is a diagram illustrating a call processing procedure according to the prior art. Here, the call processing procedure may occur between the terminal and the terminal, and may occur between the terminal and the system. For example, in a mobile communication system, a base station is a system, and a mobile communication terminal is a terminal.

As shown in FIG. 1, a call processing procedure is performed by a system / terminal calling a call to a counterpart terminal / system, and immediately before a voice channel is formed, the counterpart terminal / system transmits a Called Subscriber Answer (CSA) packet in step 32. Send to system / terminal to complete call processing procedure. At this time, the system / terminal may transmit a Called Subscriber Answer Acknowledgement (CSA ACK) packet to the counterpart terminal / system in step 34 in response to the Called Subscriber Answer (CSA) packet. Since the CSA ACK packet is an optional packet, a voice traffic channel is formed between the system / terminal and the counterpart terminal / system in step 36 even if the CSA ACK packet is not transmitted. Thus, the formation of the voice channel was made without waiting for the system / terminal to send a CSA ACK packet.

As described above, since the CSA ACK packet is optional as shown in the conventional call processing procedure, there is an advantage in that a voice channel can be formed regardless of whether or not the CSA ACK packet is received, thereby reducing the time for forming the voice channel. If it is broken without forming it has a disadvantage that can not be known.

Accordingly, an object of the present invention is to provide a call processing method for forming a voice channel which guarantees transmission of a CSA ACK packet without affecting an existing call processing procedure.

In order to achieve the above object, the present invention provides a call processing method for forming a voice channel in a communication system including one or more terminals, wherein a voice channel is transmitted after transmission and reception of a Called Subscriber Answer (CSA) packet between communication partners of the communication system. Forming a voice channel and transmitting information on a CSA ACK (Called Subscriber Answer Acknowledgement), which is the last signaling packet of a call processing procedure, to the first voice packet transmitted and received between the communication partners after the voice channel is formed.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

The present invention provides an in-band signaling field of a voice packet that is first transmitted / received through a voice channel formed after transmitting a Called Subscriber Answer (CSA) packet during a call processing for forming a voice channel between the terminal and the system or the terminal and the terminal. The CSA ACK (Called Subscriber Answer Acknowledgement), which is the last signaling packet of the call processing procedure, is transmitted to the inband signaling field to inform a communication counterpart of a transmission / reception state of the last signaling packet.

Accordingly, the terminal or the system can check whether the voice channel is disconnected or whether only the reception of the Called Subscriber Answer Acknowledgement (CSA ACK) has failed or the CSA ACK has been properly received. Through this confirmation, the UE or the system releases the connection if it does not receive the CSA ACK packet, and if the CSA ACK packet is received, transmits and receives the voice traffic packet with the confirmation that the voice channel is formed, thereby creating a reliable communication system. have. First, a configuration of a mobile communication system will be described as an example of a communication system to which the present invention can be applied.

2 is a block diagram of a general mobile communication system to which the present invention can be applied. Referring to FIG. 2, the mobile communication terminals 20 and 30 (MSs) are connected to the base station 120 through an air interface. The base station (BTS) 120 is wirelessly connected to the mobile communication terminals 20 and 30, and is received from the base station controller 120 by the base station controller 120 to the mobile communication terminal of the corresponding service area. When the call comes to the mobile communication terminal and when the call originating from the mobile communication terminal transmits it to the base station controller 130. The base station controller 130 (BSC: Base Station Center) is a general call processing such as voice call, circuit call, packet call, etc. for each mobile communication terminal. To intervene. In addition, the base station controller 130 performs a signaling operation with the MSC and performs handover.

A mobile communication center 140 (MSC: Mobile Station Center) is connected to a home location register (HLR) 150. The mobile communication exchange 140 performs a call connection exchange function for processing incoming / outgoing requests to the mobile communication terminals 110, 112, and 114, and performs a network interworking function with other mobile communication exchanges. Home location register 150 is a database that stores and manages data of mobile subscribers. The home location register 150 performs subscriber registration and deletion, and subscriber information inquiry. In such a mobile communication system, multiple access wireless communication between the base station 120 and the mobile communication terminals 20 and 30 is performed through radio frequency (RF) channels that provide physical paths for transmitting communication signals such as voice, data, and video. Is done. The call processing procedure according to the present invention is performed between the base station 120 and the mobile communication terminals 20 and 30 in the mobile communication system of FIG. This call processing procedure according to the present invention will be described with reference to FIG.

3 is a message flow diagram illustrating a call processing procedure according to the present invention. Referring to FIG. 3, when a terminal or a system performs a call processing procedure for a voice channel, and receives a Called Subscriber Answer (CSA) packet as the last signaling packet in step 202, a Called Subscriber Answer Acknowledgement (CSA ACK) packet in step 204. Is sent to the correspondent. After that, the voice traffic packets are transmitted between the terminal or the system and the communication counterpart, and the voice traffic packets are transmitted and received. The counterpart terminal or the system directly switches to the voice channel without checking whether the CSA ACK packet is received or not, and transmits and receives the voice traffic packet. Then, conventionally, the terminal or the system transmits and receives the voice traffic packet without checking whether the voice channel with the counterpart terminal or the system is disconnected or if only the reception of the CSA ACK packet has failed or the CSA ACK packet has been received. In the present invention, the terminal or the system includes the information on the CSA ACK in the voice packet transmitted after the voice channel is formed. Such a structure of a voice packet according to the present invention is shown in FIG.

4 is a diagram showing the structure of a voice packet according to an embodiment of the present invention. As shown in FIG. 4, the voice packet 230 includes a field 231 for the voice signal and a 4-bit inband signaling field 232. According to the present invention, information on the CSA ACK is carried in the in-band signaling field 232 of the voice packet. Accordingly, the present invention can easily provide information on the CSA ACK to the communication counterpart of the terminal or the system without affecting the existing call processing procedure.

In FIG. 3, the terminal or the system transmits and receives the voice packet 30 including the CSA ACK to each other in step 206 and step 208. Then, in step 210, a stable voice channel is formed between terminals or systems. Hereinafter, the call processing procedure according to the present invention will be described by dividing the CSA ACK packet sender and the CSA ACK packet sender with reference to FIGS. 5 and 6.

5 is a control flowchart showing a call processing procedure at the CSA ACK packet originating side, and FIG. 6 is a control flowchart showing a call processing procedure at the CSA ACK packet terminating side.

 First, referring to FIG. 5, the terminal or the system proceeds with a call processing procedure and finally waits for receiving a CSA packet in step 302. The terminal or the system determines in step 304 whether the CSA packet is received, and if the CSA packet is received, proceeds to step 306. The terminal or the system transmits the CSA ACK packet in step 306 and proceeds to step 308 to set the predetermined variable Num to zero. Thereafter, the terminal or the system proceeds to step 310 to determine whether the voice packet received from the communication partner includes the information on the CSA ACK. If the voice packet received from the communication partner includes information on the CSA ACK, the terminal or the system proceeds to step 320 and transmits the voice packet including the information on the CSA ACK to the communication partner. The terminal or system then sends a normal voice packet to the communication partner in step 322. A typical voice packet refers to a voice packet that is generally transmitted and received, not a voice packet in which information on a CSA ACK is included in an in-band signaling field according to the present invention.

On the other hand, if the voice packet received from the communication partner does not include the information on the CSA ACK, the terminal or the system proceeds to step 312 and increases the predetermined variable, and then in step 314 sends the voice packet including the information on the CSA ACK to the communication partner. send. Subsequently, the terminal or the system proceeds to step 316 to determine whether the predetermined variable exceeds the preset maximum limit value MAX. If the predetermined variable does not exceed the maximum limit value MAX, the terminal or the system returns to step 310. That is, the terminal or the system checks whether the CSA ACK includes information until the voice packet received from the communication partner is received a predetermined number of times. However, if the predetermined variable exceeds the maximum limit value MAX, the terminal or the system proceeds to step 318 to initialize the call processing procedure. Next, a call processing procedure at the CSA ACK packet receiver side will be described with reference to FIG. 6.

Referring to FIG. 6, the terminal or the system proceeds with a call processing procedure, finally sets a timer in step 402 and proceeds to step 404 to transmit a CSA packet to a communication counterpart. The timer is for setting a predetermined period of time after receiving the CSA ACK packet after transmitting the CSA packet, which is an ACK packet for the transmitted CSA packet. This is because the call processing does not proceed if the CSA ACK packet is continuously waited to be received. Subsequently, the terminal or the system determines whether a CSA ACK packet has been received from the communication partner in step 406, and determines whether the tamper has expired in step 408. If the terminal or the system receives the CSA ACK packet from the communication partner, the terminal proceeds to step 410. If the terminal or the system does not receive the CSA ACK packet, the terminal or the system returns to step 404 until the timer expires.

Thereafter, the terminal or the system proceeds to step 410 to set the predetermined variable Num to 0 and proceeds to step 412 to determine whether the voice packet received from the communication partner includes the information on the CSA ACK. If the voice packet received from the communication counterpart includes information on the CSA ACK, the terminal or the system proceeds to step 430 and transmits the voice packet including the information on the CSA ACK to the communication counterpart. The terminal or system then sends a normal voice packet to the communication partner in step 432. A typical voice packet refers to a voice packet which is generally transmitted and received, not a voice packet in which information on a CSA ACK is included in an in-band signaling field according to the present invention.

On the other hand, if the voice packet received from the communication partner does not include the information on the CSA ACK, the terminal or the system proceeds to step 414 and increments a predetermined variable, and then in step 416 the voice packet including the information on the CSA ACK is received. Send to communication partner. Subsequently, the terminal or the system proceeds to step 418 to determine whether the predetermined variable exceeds a preset maximum limit value MAX. If the predetermined variable has not exceeded the maximum limit value MAX, the terminal or the system returns to step 412. That is, the terminal or the system checks whether the CSA ACK includes information until the voice packet received from the communication partner is received a predetermined number of times. However, if the predetermined variable exceeds the maximum limit MAX, the terminal or the system proceeds to step 420 to initialize the call processing procedure.

According to the present invention, in a call processing for forming a voice channel, a call processing is performed in an inband signaling field of a voice packet first transmitted / received through a voice channel formed after transmitting a Called Subscriber Answer (CSA) packet. Whether the voice channel is disconnected or only receiving the CSA ACK (Called Subscriber Answer Acknowledgement) packet by sending information about the last signaling packet of the procedure, Called Subscriber Answer Acknowledgment (CSA ACK), or CSA ACK (Called Subscriber Answer Acknowledgement) You can check whether it was received correctly. Accordingly, the UE or the system releases the connection if it does not properly receive the Called Subscriber Answer Acknowledgment (CSA ACK). Send and receive This makes it possible to create a reliable communication system by reducing errors such as transmission and reception while the voice traffic channel is disconnected.

Claims (3)

A call processing method for forming a voice channel in a communication system including one or more terminals, Forming a voice channel after the transmission and reception of a Called Subscriber Answer (CSA) packet between communication partners of the communication system; And transmitting information on the CSA ACK (Called Subscriber Answer Acknowledgement), which is the last signaling packet of a call processing procedure, to the first voice packet transmitted and received between the communication partners after the formation of the voice channel. . The voice packet of claim 1, wherein the voice packet includes a field for a voice signal and an in-band signaling field, and the information on the CSA ACK is transmitted in an in-band signaling field of the voice packet. Call processing method. The method of claim 1, further comprising: initiating call processing when each of the communication partners does not receive a voice packet including information on the CSA ACK from each other more than a predetermined number of times.

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