WO2004012342A2

WO2004012342A2 - Method for controlling communication service and system thereof

Info

Publication number: WO2004012342A2
Application number: PCT/KR2003/001551
Authority: WO
Inventors: Deuk Ho Ryu
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-07-31
Filing date: 2003-07-31
Publication date: 2004-02-05
Anticipated expiration: 2005-01-31
Also published as: AU2003256096A1; AU2003256096A8; WO2004012342A3

Abstract

Disclosed is a method for controlling communication service and system thereof enabling to switch a connection of a service network in an environment where communication networks defined respectively by separate protocols interoperate reciprocally by providing flexibility of a plurality of communication services defined by specific protocols respectively. In a communication system having wireline and wireless networks interwork reciprocally, the method includes the steps of transferring a voice signal received from a terminal to the wireline network and switching a communication path of the terminal to the wireless network in accordance of QoS (quality of service) of the wireline network. The system includes a wireless terminal, a wireline terminal, and an adaptive gateway monitoring QoS of a wireline network to convert a communication path of the wireless or wireline terminal according to the QoS of the wireline network.

Description

Method for Controlling Communication Service And

System Thereof

TECHNICAL FIELD

The present invention relates to a method for controlling communication service and system thereof enabling to switch a connection of a service network in an environment where communication networks defined respectively by separate protocols interoperate reciprocally by providing flexibility for a plurality of communication services defined by specific protocols respectively.

BACKGROUND ART

Generally, all kinds of communication services use specific protocols of their own, respectively.

Applications (e.g. voice, data, etc.) of communication services are processed and handled , with a specific method following a defined protocol.

For instance, when a user demands a voice communication with a wireless phone of CDMA, user's voices are processed and handled by the method defined by a CDMA protocol so as to be transferred to a destination. However, it is unable to transfer the voices, which are processed and handled by the method defined by the CDMA protocol, through a network using another protocol different from the CDMA protocol .

Hence, in order to transfer the application (e.g. voice or data) , which is processed and handled by the method defined by the CDMA protocol, through the network using another protocol, the inputted application should be processed with the method defined by the protocol of the very network.

Namely, in order to achieve interworking between a plurality of communication systems using separate wireline or wireless communication protocols respectively, an appropriate processing for the transferred application is required.

Besides, a communication system should secure a quality of service (hereinafter abbreviated QoS) for the processed application.

In serving such a real-time application as a voice call according to a related art, the QoS is secured by such methods as 'Priority based QoS', ^ΛDual-mode operation', etc. 'Priority based QoS' is a method of securing QoS by changing each priority of real-time applications, which processes a real-time application such as voice prior to data.

This method is focused on how to use a fixed bandwidth efficiently to be appropriate for characteristics and purposes of the application.

Such a method is effective for QoS to some extent if a state of a network is good, but becomes ineffective if the network lies in congestion or becomes down for some reasons .

'Dual-mode operation' is intended to provide an application service between different networks such as WLAN (wireless LAN) and 3GPP CDMA (3^rd generation partnership project code division multiple access), WLAN and GSM (global system for mobile communications system) , and the like. Namely, QoS is secured in a manner that a communication service is provided within a service area of WLAN in accordance with a WLAN protocol or outside the service area of WLAN in accordance with CDMA or GSM protocol . Such a method just achieves a switching of a communication service according to a location of a user terminal but fails to consider QoS of the network through which the communication service is provided.

Besides, there is a VoIP (voice over Internet protocol) gateway method by Quintum technologies, inc. for securing communication QoS.

VoIP (voice over Internet protocol) is a communication service technology enabling a voice calling over Internet by transforming voice into Internet protocol (hereinafter abbreviated IP) packets that can be transferred via IP network.

The VoIP gateway method operates through a network connection between IP network and public switching telecommunication network (hereinafter abbreviated PSTN) .

When a wireline terminal (wireline phone) is connected to a VoIP gateway to use, the VoIP gateway transforms the inputted voice to fit VoIP and transfers it to the IP network. Besides, the VoIP gateway transforms IP packets inputted from the IP network into voice of PSTN and transfers it to PSTN.

In case that the voice transformed into the IP packets is transferred to the IP network, the VoIP gateway checks a quality of voice through the IP network. Once the degradation of the voice quality is notified from the IP network, the VoIP gateway switches over the communication service from IP network to PSTN so that a user is unable to sense the switch-over, thereby enabling to secure QoS.

However, such a method just secures the QoS for the wireline terminal as well as provides the interworking between the IP network and PSTN for the voice calling only.

DISCLOSURE OF THE INVENTION

Accordingly, the present invention is directed to a method for controlling communication service and system thereof that substantially obviate one or more of the problems due to limitations and disadvantages of the related art .

An object of the present invention is to provide a method for controlling communication service and system thereof appropriate for interworking between a plurality of communication systems using separate communication protocols of wireline and wireless.

Another object of the present invention is to provide a method for controlling communication service and system thereof appropriate for switching over a current service network to a useful network by measuring QoS (quality of service) of communication networks in environments where the communication networks respectively defined by separate protocols interwork.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings .

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, in a communication system having wireline and wireless networks interwork reciprocally, a method of controlling communication service according to the present invention includes a first step of transferring a voice signal received from a terminal to the wireline network and a second step of switching a communication path of the terminal to the wireless network in accordance of QoS (quality of service) of the wireline network.

In another aspect of the present invention, in a communication system having IP (Internet protocol) and CDMA networks interwork reciprocally, a method of controlling communication service includes a first step of transferring a voice signal received from a CDMA phone to the IP network, a second step of monitoring QoS (quality of service) of the IP network, and a third step of switching a communication path of the CDMA phone to the CDMA network in accordance of the QoS (quality of service) of the monitored IP network.

In another aspect of the present invention, in a communication system having IP (Internet protocol) and CDMA networks interwork reciprocally, a method of controlling communication service includes a first step of transferring a voice signal received from a wireline phone to the IP network, a second step of monitoring QoS (quality of service) of the IP network, and a third step of switching a communication path of the wireline phone to the CDMA network in accordance of the QoS (quality of service) of the monitored IP network.

In another aspect of the present invention, in a communication system having wireline and wireless networks interwork reciprocally, a method of controlling communication service includes a first step of checking an application received from a terminal, a second step of converting the received application to a packet according to a transmission standard of the wireline network, and a third step of transferring the converted packet to the wireline network. In another aspect of the present invention, in a communication system having IP (Internet protocol) and CDMA networks interwork reciprocally, a method of controlling communication service includes a first step of judging whether an application is currently received from a CDMA phone or a wireline phone, a second step of converting the received application to a CDMA signal according to a transmission standard of the CDMA network if it is judged that the application is received from the wireline phone, and a third step of transferring the converted CDMA signal to the IP network.

In a further aspect of the present invention, a system for controlling communication service includes a wireless terminal, a wireline terminal, and an adaptive gateway monitoring QoS (quality of service) of a wireline network to convert a communication path of the wireless or wireline terminal according to the QoS of the wireline network.

Preferably, the adaptive gateway includes a QoS monitor/controller monitoring the QoS of the wireline network, the QoS monitor/controller commanding a communication path switch according to the QoS of the wireline network and a selector switching the communication path of the wireless or wireline terminal to a wireless network according to a command of the QoS monitor/controller.

In a further aspect of the present invention, a system for controlling communication service includes a wireless terminal following a transmission standard of a wireless network, a wireline terminal following a different transmission standard from the transmission standard of the wireless network, and an adaptive gateway transferring each application of the wireless and wireline terminals to one wireline network

Preferably, the adaptive gateway includes a vocoder converting the application of the wireline terminal to a signal having a rate according to the transmission standard of the wireless network, the vocoder bypassing the application of the wireless terminal.

In another further aspect of the present invention, in a communication service based on VoIP to an IP (Internet protocol) network, a communication service control system includes a CDMA phone, a wireline phone, and an adaptive gateway converting a voice signal of the CDMA or wireline phone to an IP packet to transfer to the IP network, the adaptive gateway monitoring QoS (quality of service) of the IP network to switch a communication path of the CDMA or wireline phone according to the QoS of the IP network.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings :

FIG. 1 illustrates a general block diagram of a system for controlling communication service according to the present invention;

FIG. 2A and FIG. 2B illustrate block diagrams of a system for controlling communication service according to embodiments of the present invention, respectively;

FIG. 3 illustrates a flowchart of a protocol adaptation procedure according to the present invention;

FIG. 4 illustrates a flowchart of a communication service control procedure according to a first embodiment of the present invention; and

FIG. 5 illustrates a flowchart of a communication service control procedure according to a second embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. FIG. 1 illustrates a general block diagram of a system for controlling communication service according to the present invention.

System structure and operation of system elements are explained by referring to FIG. 1 as follows. A service control system according to the present invention includes an adaptive gateway 100, terminals 200 and 300, a wireless network 400, and a wireline network 500.

The terminals 200 and 300 are a wireless terminal 200 communicating via air interface and a wireline terminal 300 communicating via communication line, respectively.

The wireless terminal 200 is a conventional mobile terminal securing mobility such as a CDMA phone following a CDMA protocol and a GSM phone following a GSM protocol . Specifically, as the wireless terminal 200, a Wi-Fi phone according to such standards for wireless LAN developed by IEEE working group as 802.11, 802.11a, 802.11b, and 802. llg can be used. Yet, in the present invention, a Wi-Fi module supporting VoIP/VoWLAN and data service is loaded on the phone .

The wireline terminal 300 is a terminal requiring a communication line such as a wireline phone or a personal computer. Specifically, in case of the wireline phone, an analog or digital phone can be used. The present invention is equipped with an instrumental construction for converting a signal of an analog phone to a digital signal (PCM) , which will be explained later.

Moreover, a WLAN phone, a Bluetooth phone, and the like can be used as the terminals of the present invention as well as PDA having a CDMA card therein.

The adaptive gateway 100 includes a RF unit 110 taking charge of roles of a base station controller (BSC) and a base station transceiver subsystem (BTS) of a radio system following a radio communication protocol, and further includes an adaptive controller 120 for a communication service control of the present invention, an IP unit 130, and a selector 140. Besides, the adaptive gateway 100 can be fabricated into a card form to insert in the RF wireless terminal, thereby enabling to carry out a gateway function described in the following.

The RF unit 110 includes a nano BTS 111 playing a role of BTS of the wireless network 400 and a nano BSC 112 playing a role of BSC of the wireless network 400.

Compared to BTS and BSC of the wireless network 400, the nano BTS 111 and BSC 112 have reduced service reception capability according to the number of users only. Specifically, the nano BTS 111 includes a repeater taking charge of signal amplification and relay inside.

Specifically, the nano BTS 111 and wireless terminal 200 establish a dedicated channel to communicate with each other via the established channel. In other words, the wireless terminal 200 has priority in achieving a communication link to the nano BTS 111 with default. The adaptive controller 120 includes a first vocoder 121, a second vocoder 122, and a controller 123. The first vocoder 121 converts a voice signal of an analog wireline terminal to a signal fitting a transmission standard of a digital wireline terminal. And, the second vocoder 122 converts a signal of the digital wireline terminal and the digitally-converted signal of the analog wireline terminal to signals fitting a transmission standard of the wireless network 400.

In addition, a coder/decoder (not shown in the drawing) for coding data flowing from the wireline terminal 300 or decoding data packets that will be transferred to the wireline terminal 300 is included in the adaptive controller 120.

An example of vocoding by the adaptive controller 120 is explained in the following. First of all, the controller 123 analyzes whether an inputted voice signal of the wireline terminal 300 is an analog signal or a digital signal. If the inputted signal is the analog signal, a signal path is opened to the first vocoder 121 for the corresponding inputted signal. The first vocoder 121 converts the inputted analog voice signal to a digital voice signal (e.g. 64kbps PCM signal) and then transfers it to the second vocoder 122. And, the second vocoder 122 transforms the inputted digital voice signal into a signal fitting a transmission standard of the wireless network.

On the other hand, if the inputted signal is a digital signal (e.g. 64kbps PCM signal), the controller 123 opens a signal path to the second vocoder 122 for the inputted signal. The second vocoder 122 then transforms the inputted digital voice signal into a signal fitting the transmission standard of the wireless network. And, the second vocoder 122 decodes a voice packet, which will be transferred to the wireline terminal 300, into a digital signal fitting a standard of a digital wireline terminal. If the decoded digital signal is the signal that will be transferred to the corresponding wireline terminal, the first vocoder 121 converts the digital signal having been converted by the second vocoder 122 to an analog signal again.

In addition to the example, if the wireless network 400 is a CDMA network and data is inputted from the wireline terminal 300 like a computer, the coder/decoder (not shown in the drawing) transforms the inputted data into a signal fitting CDMA transmission standards. On the contrary, data of the CDMA transmission standards, which will be transferred to the wireline terminal 300, is transformed into a PCM signal fitting the standard of the wireline terminal 300.

For another example, if the wireless network is a CDMA network and a voice signal (64kbps PCM signal) is inputted from a wireline phone, the second vocoder 122 converts the 64kbps PCM (pulse code modulation) signal to an 8kbps CDMA signal. On the contrary, an 8kbps CDMA signal that will be transferred to the wireline phone is converted to a 64kbps PCM signal. However, in the present invention, since the wireline terminal 300 does not use the 64kbps PCM signal all the time, the second vocoder 122 converts a signal (WLAN signal) , which is not the 64kbps PCM signal, to a 64kbps PCM signal and then converts it to an 8kbps CDMA signal again. Namely, the second vocoder 122 converts 8X kbps PCM signals, where X is a natural number, to a basic 64kbps PCM signal and then converts it to an 8kbps CDMA signal again. When receiving a hand-off command, the controller 123 of the adaptive controller 120 changes an output path of the second vocoder 122. Namely, when the hand-off command is received for a signal which is being transferred to an IP network, the output path is changed so that an output signal of the second vocoder 122 is transferred to the wireless network. On the contrary, when receiving a hand- off recovery command for a signal which is being transferred to the wireless network after hand-off, the controller 123 changes an output path so that an output signal of the second vocoder 122 is transferred to the IP network.

Moreover, once hand-off of the signal which is being transferred to the IP network is completed, the controller 123 drops the output path to the IP network side. Thereafter, once the hand-off recovery for the signal which is being transferred to the wireless network is completed, the controller 123 drops the output path to the wireless network side.

The IP unit 130 includes a packetizer/depacketizer 131 and a QoS (quality of service) monitor/controller 132. The packetizer/depacketizer 131 changes a signal that will be outputted to the wireline network 500 into a packet fitting the transmission standard of the wireline network 500 or recovers a packet inputted from the wireline network 500.

Namely, the IP unit 130 changes the application to be transferred into a packet fitting a protocol standard of the wireless network 400 or changes the packet inputted via the wireline network 500 into the original application. Moreover, the IP unit 130 has a routing function.

The QoS monitor/controller 132 monitors QoS of the wireline network 500 after a packet is transferred to the wireline network 500 , and manages hand-off using the monitored data. Specifically, if it is sensed that QoS of the wireline network 500 is degraded due to some reasons, the QoS^' monitor/controller 132 operates in conjunction with the selector 140 that will be described later, thereby carrying out hand-off for the terminal which is signaling and controlling a signal transfer to the wireline network 500.

For one instance, if the wireless and wireline networks 400 and 500 are CDMA and IP networks, respectively and when a packetized CDMA voice signal is being transferred to the IP network from a CDMA terminal as the wireless terminal 200, the QoS monitor/controller 132 interworks with the selector 140 to hand off the signal transfer from the IP network to the CDMA network if failure of the IP network is detected. For another instance, if the wireless and wireline networks 400 and 500 are CDMA and IP networks, respectively and when a CDMA voice signal converted from a PCM voice signal having been transferred from a wireline phone as the wireline terminal 300 is transferred to the IP network as a packet form, the QoS monitor/controller 132 interworks with the selector 140 to hand off the signal transfer from the IP network to the CDMA network if failure of the IP network is detected.

The above-mentioned selector 140 is directed by the QoS monitor/controller 132 to interwork with the RF unit 110, thereby executing practical hand-off from the wireline network 500 to the wireless network 400.

Specifically, in order to achieve the hand-off to the wireless network 400 for the wireline terminal 300, the selector 140 operates like the wireless terminal makes a phone call to the wireless network 400, thereby executing call initiation/setup to the wireless network 400. More specifically, it is able to hand off 'the signal transfer to the wireline 500 of the wireline terminal 300' to 'the signal transfer to the wireless network 400' after the call setup has been completed between the wireline terminal 300 and the wireless network 400. Hence, the selector 140 takes place of the call setup between the wireline terminal 300 and the wireless network 400. Particularly, an MSM chipset that will be described in the following takes place of the call setup between the wireline terminal 300 and the wireless network 400.

If the wireless network 400 is a CDMA network, the selector 140 includes a CSM (cell site modem) chipset, an MSM (mobile system modem) chipset, and a controller. In this case, the wireless terminal 200 is a CDMA terminal. The CSM chipset is built in BTS as one of the elements of the CDMA network, interworks with the CDMA terminal to carry out call setup, traffic transmission, etc., and operates in conjunction with the MSM chipset built in the selector 140 to carry out hand-off. The MSM chipset is identical to that built in the CDMA terminal, and interworks with BTS as one of the elements of the CDMA network to carry out call setup, traffic transmission, and coding/decoding or vocoding. Specifically, the MSM chipset operates in conjunction with the CSM chipset to carry out hand-off.

In the present invention, the CSM and MSM chipsets may be loaded inside the nano BTS 111. Namely, if the nano BTS 111 has the selector loaded 140 therein, the nano BTS 111 according to the present invention has both of the CSM and MSM chipsets loaded inside, which is different from the fact that BTS of the conventional CDMA network has the CSM chipset loaded therein only.

When the hand-off command is directed from the QoS monitor/controller 132, the controller has the CSM and MSM chipsets carry out practical hand-off. And, the controller informs the adaptive controller 120 and the QoS monitor/controller 132 of the completion of hand-off if hand-off ends .

Thus, since the MSM chipset has the functions of the coder/decoder (not shown in the drawing) and vocoders 121 and 122 if the selector 140 is constituted with the CSM chipset, MSM chipset, and controller, it is unnecessary to add supplementary coder/decoder and vocoders thereto. Hence, FIG. 1 depicts the logical constitution. Yet, the first vocoder 121 is separately added thereto for the vocoding characteristics. Preferably, the present invention implements the selector 140 having the CSM and MSM chipsets and controller built inside with a single module together with the QoS monitor/controller 130.

The wireless network 400 may be one of CDMA network, GSM network, etc. And, the wireline network 500 may be one of IP network, Ethernet, etc.

A communication service control operation carried out by the above-described elements is explained as follows.

Basically, the wireless and wireline terminals 200 and 300 carry out a registration procedure to the adaptive gateway 100. Hence, the adaptive gateway 100 recognizes a target terminal to serve. For example, phone numbers and/or identification numbers granted to the terminals respectively are registered to the adaptive gateway 100. Hence, when there is a currently-received application (or signal) , the adaptive gateway 100 enables to recognize whether the received application (or received signal) is transferred from the previously registered terminal or not. First of all, an example that the wireless terminal 200 wants to send a voice signal to the wireline network 500 is explained as follows. In order to send the voice signal, the wireless terminal 200 completes a call setup procedure with the RF unit 110. For example, signaling for the call setup between the wireless terminal 200 and RF unit 110 follows the standard of SIP (session initiation protocol) or ITU-T H.323.

After the call setup, the voice signal of the wireless terminal 200 passes through the RF unit 110. The voice signal outputted from the RF unit 110 bypasses the vocoders 121 and 122 and is then transferred to the packetizer/depacketizer 131.

The packetizer/depacketizer 131 converts the voice signal, which is outputted from the RF unit 110, to a packet fitting the transmission standard of the wireline network 500 and then transfers the corresponding packet to the wireline network 500.

In this case, the QoS monitor/controller 132 monitors QoS of the wireline network 500.

If it is detected that the QoS of the wireline network 500 is degraded due to some reasons, the QoS monitor/controller 132 sends a seamless hand-off command to the controller of the selector 140 and the controller 123 of the adaptive controller 120. Yet, in this case, the voice signal of the wireless terminal 200 is transferred to the wireline network 500 as well. Namely, the controller 123 of the adaptive controller 120 opens a new output path to the RF unit side 110 while maintaining an output path toward the previous wireline network 500 of the second vocoder 122.

The controller of the selector 140 transfers a seamless hand-off trigger/initiation message to the CSM and MSM chipsets . Accordingly, the CSM and MSM chipsets carry out practical hand-off to the wireless network 400, whereby the path through which the wireless terminal 200 sends the voice signal to the wireline network 500 is switched to the wireless network 400. While hand-off is in progress, the voice signal of the wireless terminal 200 is simultaneously sent to the wireline network 500 as well. In this case, the hand-off carried out by the CSM and MSM chipsets is hard hand-off identical to that recommended by CDMA standards.

Once the hand-off to the wireless network 400 is completed, the controller of the selector 140 transfers a seamless hand-off completion message to the adaptive controller 120 and the QoS monitor/controller 132. The QoS monitor/controller 132 then drops the path toward the wireline network 500 through which the voice signal of the wireless terminal 200 is transferred. And, the QoS monitor/controller 132 keeps monitoring the QoS of the wireline network 500. And, the controller 123 of the adaptive controller 120 drops the output path toward the wireline network side of the second vocoder 122.

If it is detected that the QoS of the wireline network 500 is recovered, the QoS monitor/controller 132 sends a seamless hand-off recovery command to the controller of the selector 140 and the controller 123 of the adaptive controller 120. Yet, in this case, the voice signal of the wireless terminal 200 is transferred to the wireless network 400 as well, and the packetizer/depacketizer 131 is enabled. The controller 123 of the adaptive controller 120 opens a new output path toward the previous wireline network side while maintaining an output path toward the RF unit 110 after the hand-off of the second vocoder 122.

The controller of the selector 140 transfers a seamless hand-off recovery trigger/initiation message to the CSM and MSM chipsets.

Accordingly, the CSM and MSM chipsets carry out practical hand-off to the wireline network 500, thereby switching the path, through which the wireless terminal 200 sends the voice signal to the wireless network 400, to the wireline network 500. When the hand-off recovery is in progress, the voice signal of the wireless terminal 200 is simultaneously sent to the wireless network 400 as well.

Once the hand-off recovery to the wireline network 500 is completed, the controller of the selector 140 transfers a seamless hand-off recovery completion message to both of the adaptive controller 120 and the QoS monitor/controller 132. The QoS monitor/controller 132 then drops the path toward the wireless network 400 to which the voice signal of the wireless terminal 200 was transferred. The controller of the adaptive controller 120 drops the output path toward the RF unit side of the second vocoder 122. And, the QoS monitor/controller 132 keeps monitoring the QoS of the wireline network 500. Explained in the following is an example that the wireline terminal 300 wants to transfer a voice signal to the wireline network 500.

First of all, the wireline terminal 300 transmits a voice signal to the adaptive gateway 100. The controller 123 of the adaptive controller 120 analyzes whether the received voice signal is an analog voice signal or a digital voice signal . The vocoder 122 of the adaptive gateway 100 converts the received voice signal of the wireline terminal 300 to a radio standard signal fitting the transmission standard of the wireless network 400 and transfers the radio standard signal to the packetizer/depacketizer 131.

Specifically, if the received voice signal is the analog voice signal, the controller 123 inputs the received voice signal to the first vocoder 121 so that the first vocoder 121 converts the analog signal to the digital signal. And, the controller 123 controls the converted digital signal to be inputted to the second vocoder 122.

If the received voice signal is the digital voice signal, the controller 123 directly inputs the received voice signal to the second vocoder 122 so that the second vocoder 122 converts the received digital signal to a signal of the transmission standard of the wireless network 400.

The second vocoder 122 of the adaptive gateway 100 converts the received voice signal of the wireline terminal 300 to a radio standard signal fitting the transmission standard of the wireless network 400. Namely, the second vocoder 122 converts the voice signal of the wireline phone to a CDMA signal fitting the CDAM transmission standard. Specifically, the first vocoder 121 converts the analog signal inputted from the wireline phone to a 64kbps PCM signal. The second vocoder 122 converts the 64kbps PCM signal inputted from the wireline phone or the first vocoder 121 to an 8kbps CDMA signal to transfer to the IP network and then transfers the 8kbps CDMA signal to the packetizer/depacketizer 131. The packetizer/depacketizer 131 converts the converted radio standard signal to a packet fitting the transmission standard of the wireline network 400 and then transfers the packet to the wireline network 500.

In this case, the QoS monitor/controller 132 monitors the QoS of the wireline network 500.

If it is detected that the QoS of the wireline network 500 is degraded due to some reasons, the QoS monitor/controller 132 sends a seamless hand-off command to both of the controller of the selector 140 and the controller 123 of the adaptive controller 120. Yet, in this case, the voice signal of the wireless terminal 200 is transferred to the wireline network 500 as well. Namely, the controller 123 of the adaptive controller 120 opens a new output path to the RF unit 110 while maintaining an output path toward the previous wireline network 500 of the second vocoder 12 .

The controller of the selector 140 transfers a seamless hand-off trigger/initiation message to the CSM and MSM chipsets . Accordingly, the MSM chipset operates like the wireless terminal makes a phone call to the wireless network 40 for hand-off to the wireless network 400 for the wireline terminal 300, thereby carrying out call initiation/setup toward the wireless network. Thus, the call setup toward the wireless network 400 of the wireline terminal 300 is successfully completed. Thereafter, the CSM and MSM chipsets carry out practical hand-off to the wireless network 400, whereby the path through which the wireline terminal 300 sends the voice signal to the wireline network 500 is switched to the wireless network 400. While hand-off is in progress, the voice signal of the wireline terminal 300 is simultaneously sent to the wireline network 500 as well.

Once the hand-off to the wireless network 400 is completed, the controller of the selector 140 transfers a seamless hand-off completion message to the adaptive controller 120 and the QoS monitor/controller 132. Then, the controller 123 in the adaptive controller 120 switches the output path of the second vocoder 122 to the side of the RF unit 110 and the QoS monitor/controller 132 drops the path toward the wireline network 500 through which the voice signal of the wireline terminal 300 is transferred. And, the QoS monitor/controller 132 keeps monitoring the QoS of the wireline network 500.

If it is detected that the QoS of the wireline network 500 is recovered, the QoS monitor/controller 132 sends a seamless hand-off recovery command to the controller of the selector 140 and the adaptive controller 120. Yet, in this case, the voice signal of the wireline terminal 300 is transferred to the wireless network 400 as well, and the packetizer/depacketizer 131 is enabled. The controller 123 of the adaptive controller 120 opens a new output path toward the previous wireline network side while maintaining an output path toward the RF unit 110 after the hand-off of the second vocoder 122.

The controller of the selector 140 transfers a seamless hand-off recovery trigger/initiation message to the CSM and MSM chipsets. Accordingly, the CSM and MSM chipsets carry out practical hand-off to the wireline network 500, thereby switching the path, through which the wireline terminal 300 sends the voice signal to the wireless network 400, to the wireline network 500. When the hand-off recovery is in progress, the voice signal of the wireline terminal 300 is simultaneously sent to the wireless network 400 as well.

Once the hand-off recovery to the wireline network 500 is completed, the controller of the selector 140 transfers a seamless hand-off recovery completion message to the adaptive controller 120 and the QoS monitor/controller 132 and the MSM chipset releases a previously set call of the wireline terminal 300. The controller 123 in the adaptive controller 120 switches the output path of the second vocoder 122 to the side of the IP unit 130 and the CSM and MSM chipsets drop the path toward the wireless network 400 to which the voice signal of the wireline terminal 300 was transferred so far. And, the QoS monitor/controller 132 keeps monitoring the QoS of the wireline network 500.

It is important that execution of hand-off is judged by taking a threshold, which is previously set, as a reference when the QoS monitor/controller 132 monitors the QoS of the wireline network 500.

Examples for the hand-off execution judgment of the QoS monitor/controller 132 are explained as follows.

First of all, the QoS monitor/controller 132 previously set up a first threshold, a second threshold, and a third threshold for hand-off.

Once the QoS of the wireline network 500 drops below the first threshold, it is judged that the QoS becomes degraded. If the QoS keeps dropping from the first threshold with a prescribed rate and reaches the second threshold, hand-off is then executed.

Thereafter, hand-off recovery is executed if the QoS stably exceeds the third threshold set to be higher than the second threshold. In this case, 'the QoS stably exceeds...' means that the QoS of the wireline network 500 keeps increasing with a prescribed rate from the second threshold to exceed the third threshold instead of the unstable case that the QoS swings centering around the third threshold. Namely, the present invention does not execute the seamless hand-off recovery always if the QoS exceeds the third threshold.

In the above explanation, the adaptive gateway 100 supervises or manages hand-off. Namely, the QoS monitor/controller 132 monitors the QoS of the wireline network 500 to direct the hand-off command. Yet, the present invention pays special regard to the fact that the terminals 200 and 300 direct the hand-off command. The case that the terminals 200 and 300 direct the hand-off command means that the hand-off command is directed to the adaptive gateway 100 since a currently calling terminal user judges that a conversation phase is poor. Each of the terminals 200 and 300 further includes an auxiliary key for the hand-off command. The user presses the hand-off key to send the seamless hand-off command to the controller of the selector 140 when judging that the conversation phase is poor due to some reasons. Accordingly, the controller of the selector 140 transfers the seamless hand-off trigger/initiation message to the CSM and MSM chipsets.

Subsequent operation is identical to that of the case that the previously mentioned adaptive gateway 100 manages the hand-off. And, the hand-off recovery is managed to execute by the QoS monitor/controller 132 of the adaptive gateway 100.

FIG. 2A and FIG. 2B illustrate block diagrams of a system for controlling communication service according to embodiments of the present invention, respectively.

Referring to FIG. 2A and FIG. 2B, a system according to the present invention is implemented for a communication service control through protocol adaptation between CDMA and IP networks.

A communication service control system according to the present invention includes an adaptive gateway, a CDMA phone, a wireline phone, a CDMA network, and an IP network. The adaptive gateway includes a RF unit playing roles of BTS (base station transceiver subsystem) and BSC (base station controller) following a CDMA protocol, and further includes an adaptive controller for a communication service control of the present invention, an IP unit, and a selector.

The RF unit includes a nano BTS taking charge of a role of BTS of the CDMA network and a nano BSC taking charge of a role of BSC of the CDMA network. The nano BTS and BSC have a service reception capability according to the number of users, which is reduced more than that of

BTS and BSC of the CDMA network.

And, the nano BTS includes a repeater taking charge of signal amplification and relay inside. Specifically, the nano BTS and the CDMA phone establish a dedicated channel to communicate with each other via the established channel. In other words, the

CDMA phone has priority in achieving a communication link to the nano BTS with default . The adaptive controller includes a first vocoder, a second vocoder, and a controller, and further includes a coder/decoder. The coder/decoder and vocoders convert an application (voice or data) of the wireline phone to a CDMA signal fitting a CDAM transmission standard.

Namely, the coder/decoder converts data inputted from the wireline phone to the CDMA signal fitting the CDMA transmission standard.

The first vocoder converts an analog signal inputted from an analog wireline phone to a 64kbps PCM signal to output to the second vocoder. In order to transfer the 64kbps PCM signal inputted from a digital wireline phone or the first vocoder to the IP network, the second vocoder converts the 64kbps PCM signal to an 8kbps CDMA signal to transfer to the IP unit.

Since the application of the CDMA phone is already the 8kbps CDMA signal, no signal conversion of the vocoder occurs for the signal of the CDMA phone. Namely, the vocoder is bypassed.

The controller of the adaptive controller changes an output path of the second vocoder in accordance with a hand-off command, and designates a path to the vocoder that will perform a signal processing according to characteristics of the signal inputted from the wireline phone as well.

The IP unit lying just in front of the IP network includes a packetizer/depacketizer and a QoS monitor/controller.

The packetizer/depacketizer according to the present invention handles the CDMA signal of 8kbps only. Namely, the packetizer/depacketizer changes the 8kbps CDMA signal, which is outputted to the IP network, into a packet fitting a transmission standard of the corresponding IP network or releases an IP packet inputted from the IP network.

If the IP packet is a packetized 64kbps PCM voice signal, the IP packet is not separately decoded after the packet release. Yet, if the inputted IP packet is a packetized 8kbps CDMA signal, the vocoder decodes the IP packet into a 64kbps PCM signal after the packet release.

The QoS monitor/controller monitors QoS of the IP network after the packet has been transferred to the IP network, directs a hand-off command based on the monitored data, drops a path of the IP network after the completion of hand-off, and restores the path of the IP network if the QoS of the IP network is recovered.

Specifically, the QoS of the IP network can be degraded due to various factors such as transmission delay, packet loss, etc. If it is judged that a transmission environment of the current IP network keeps being degraded since the QoS of the IP network is lowered below a previously set first threshold, the QoS monitor/controller operates in conjunction with the selector to execute the hand-off for the terminal (CDMA phone or wireline phone) which is sending a voice signal.

For one example, if failure of the IP network is detected when a packetized CDMA voice signal of the CDMA phone is being transferred to the IP network, the QoS monitor/controller interworks with the selector to hand off 'a signal transfer to the IP network' to 'a signal transfer to the CDMA network' .

For another example, when an 8kbps CDMA voice signal, which is converted from a 64kbps PCM voice signal having been transferred from the wireline phone, is transferred as a packet to the IP network, if failure of the IP network is detected, the QoS monitor/controller interworks with the selector to hand off 'a signal transfer to the IP network' to 'a signal transfer to the CDMA network' .

The selector receiving a hand-off command of the QoS monitor/controller interworks with the RF unit to execute practical hand-off from the IP network to the CDMA network.

Separate call setup is unnecessary for the wireline phone to send a voice signal to the IP network. Yet, in order to achieve hand-off to the CDMA network, a signal transfer is possible only after the wireline phone has set up a call to the CDMA network. Since the wireline phone has no call setup function to the CDMA network, the selector takes the place of such a function.

Namely, for the hand-off to the CDMA network for the wireline phone, the selector works like the CDMA phone makes a phone call to the CDMA network before the hand-off, thereby executing call initiation/setup to the CDMA network. The call setup or hand-off for the wireline phone is enabled by loading MSM and CSM chipsets inside the selector. Namely, the selector includes the CSM chipset and the MSM chipset . The CSM chipset carries out call setup and traffic transmission of the CDMA phone and the wireline phone, and operates in conjunction with the MSM chipset to carry out hand-off .

The MSM chipset is built in the CDMA phone as well, and interworks with BTS of the CDMA network to carry out call setup, traffic transmission, and coding/decoding or vocoding. Specifically, the MSM chipset operates in conjunction with the CSM chipset to carry out hand-off.

And, a controller is loaded inside the selector as well . The controller makes the CSM and MSM chipsets execute practical hand-off when the QoS monitor/controller directs a hand-off command, and initializes the CSM and MSM chipsets if the hand-off ends. Once the hand-off ends, the controller informs the adaptive controller and the QoS monitor/controller of hand-off completion. Accordingly, the controller of the adaptive controller changes an output path of the second vocoder to the wireless network side and the QoS monitor/controller drops the communication path to the IP network. Thus, the selector including the CSM chipset, MSM chipset, and controller enables to carry out functions of the coder/decoder and vocoder. Instead, the coder/decoder and vocoder may be constituted separately.

A pair of cases of 'vocoder bypass' carried out by the system according to the present invention will be explained in detail as follows. 1. 'Vocoder bypass' is executed in the present invention when an application is transmitted/received between wireless terminals registered to the adaptive gateway.

Namely, as the wireless terminal (s) follows the transmission standard of the wireless network in the present invention, a signal transmitted from the wireless terminal is already appropriate for the transmission standard of the wireless network.

An operation that BSC of the previous wireless network carries out vocoding for a signal (64kbps) fitting the transmission standard of PSTN is not required. And, in the present invention, a signal is transmitted to the IP network at a transmission rate vocoded in the wireless terminal itself. Hence, separate vocoding inside the adaptive gateway is unnecessary.

For instance, a signal of a transmitting side wireless terminal, which vocodes 64kbps signal into 8kbps signal to transmit, is directly converted to IP packet without performing a vocoding procedure, and the adaptive gateway of a receiving side transfers the 8kbps signal of which packet is released only is directly transferred to a receiving side wireless terminal . 2. In the present invention, 'vocoder bypass' is carried out when an application is transmitted/received between wireless and wireline terminals registered to the adaptive gateway. First of all, in case that the wireless and wireline terminals registered to the adaptive gateway of the present invention are transmitting and receiving sides, respectively, 'vocoder bypass' is carried out in a transmitting side adaptive gateway. On the other hand, in case that the wireless and wireline terminals registered to the adaptive gateway of the present invention are receiving and transmitting sides, respectively, 'vocoder bypass' is carried out in a receiving side adaptive gateway. In short, vocoding is carried out on transmission/reception signals of the wireline terminal only and transmission/reception signals of the wireless terminal are vocoder-bypassed.

A protocol adaptation procedure carried out by the above-described elements is explained by referring to FIG. 3 as follows.

FIG. 3 illustrates a flowchart of a protocol adaptation procedure according to the present invention, in which a voice signal of a CDMA or wireline phone like VoIP (voice over IP) is served via IP.

First of all, a CDMA or wireline phone basically carries out a registration procedure to an adaptive gateway (SI) .

If the registered CDMA or wireline phone makes a voice signal transmission request toward an IP network (S2) , the adaptive gateway firstly checks which terminal has made the transmission request (S3) .

If it is judged that the current transmission request is made by the CDMA phone (S4) , a call setup is carried out between the CDMA phone and an RF unit of the adaptive gateway (S5) . Once the call setup for the CDMA phone is completed (S6) , a dedicated communication channel is established between the CDMA phone and the RF unit (S7) . Namely, the CDMA phone has a priority of communication link to a nano BTS with default. The CDMA phone transmits an 8kbps CDMA signal via the established dedicated communication channel (S8) , and the RF unit transfers the received 8kbps CDMA signal to a packetizer/depacketizer (S9) .

The packetizer/depacketizer converts the inputted 8kbps CDMA signal to IP packet according to a transmission standard of the IP network and then transfers the IP packet to the IP network (S10, Sll) .

A QoS monitor/controller monitors QoS of the IP network from a time point that the dedicated communication channel is established between the CDMA phone and the RF unit (S12) .

On the other hand, if it is judged that the current transmission request is made by the wireline phone (S4) , a wireline communication channel is established between the wireline phone and the adaptive gateway (S13) .

The wireline phone transmits a signal via the established wireline communication channel (S14) , and the adaptive gateway checks characteristics and transmission rate of the received signal (S15) . This is because the wireline phone does not always transmit a PCM signal but may transmit an analog signal by an analog wireline phone. Moreover, the transmission rate of the PCM signal varies in accordance with coding and compression methods.

If the received signal is the PCM signal and the PCM signal is a 64kbps PCM signal (S16, S17) , a vocoder of the adaptive gateway converts the received 64kbps PCM signal to an 8kbps CDMA signal (S19) . On the other hand, if the received signal is not the PCM signal but an analog signal (S16) , another vocoder converts the received signal to a 64 kbps PCM signal (S18) . Moreover, if the received signal is a PCM signal but is not a 64kbps PCM signal (S17) , the vocoder converts the received signal to a 64 kbps PCM signal and then converts the converted 64kbps PCM signal to a 8kbps CDMA signal (S18, S19) . Namely, in the present invention, standardization of the received PCM signal is firstly carried out and then the standardized PCM signal is converted to the CDMA signal again.

The packetizer/depacketizer converts the 8kbps CDMA signal outputted from the vocoder to IP packet according to the transmission standard of the IP network and then transfers the IP packet to the IP network (S20, S21) .

The QoS monitor/controller monitors the QoS of the IP network from a time point that the wireline communication channel for the wireline phone is established (S22) .

A communication service control procedure carried out by the above-described elements is explained by referring to FIG. 4 and FIG. 5 as follows.

FIG. 4 illustrates a flowchart of a communication service control procedure according to a first embodiment of the present invention, in which a voice signal of a CDMA phone is served via IP like VoIP (voice over IP) .

First of all, a CDMA phone basically carries out a registration procedure to an adaptive gateway (S101) . If the registered CDMA phone makes a voice signal transmission request toward an IP network (S102) , a call setup is carried out between the CDMA phone and an RF unit of the adaptive gateway (S103) .

Once the call setup is completed (S104) , a dedicated communication channel is established between the CDMA phone and the RF unit (S105) . Namely, the CDMA phone has a priority of communication link to a nano BTS with default.

The CDMA phone transmits an 8kbps CDMA signal via the established dedicated communication channel (S106) , and the RF unit transfers the received 8kbps CDMA signal to a packetizer/depacketizer (S107) .

The packetizer/depacketizer converts the inputted 8kbps CDMA signal to IP packet according to a transmission standard of the IP network and then transfers the IP packet to the IP network (S108, S109) .

A QoS monitor/controller monitors QoS of the IP network from a time point that the dedicated communication channel is established between the CDMA phone and the RF unit (SUO) .

If the QoS of the IP network keeps being lowered after being lowered below a first threshold set up to determine the execution of hand-off (Sill) , the QoS monitor/controller sends a seamless hand-off command to a controller of a selector (S112) .

In this case, a communication path of the CDMA phone maintains the IP network. The controller of the selector transfers a seamless hand-off trigger/initiation message to CSM and MSM chipsets (S113) .

Accordingly, the CSM and MSM chipsets hand off the

CDMA phone to a CDMA network (S114) . Namely, the CSM and MSM chipsets switch a communication path so that the voice signal of the CDMA phone is received by BTS of the CDMA network .

Once hand-off for the CDMA phone is completed (S115) , the controller of the selector transfers a seamless hand- off completion message to the QoS monitor/controller

(S116) .

As the seamless hand-off completion message is inputted, the QoS monitor/controller drops the communication path toward the IP network (S117) .

Yet, the QoS monitor/controller keeps monitoring the QoS of the IP network afterward (S118) . If the QoS of the IP network, which becomes more satisfactory, keeps increasing to exceed a third threshold after exceeding a second threshold set up for determining hand-off execution (S119) , the QoS monitor/controller sends a seamless hand-off recovery command to the controller of the selector (S120) .

In this case, the communication path of the CDMA phone maintains the CDMA network.

Specifically, even if the QoS of the IP network simply exceeds the third threshold, the QoS monitor/controller does not send the seamless hand-off recovery command to the controller of the selector in direct. Namely, in case that the QoS of the IP network swings centering around the third threshold, ex. in case that the IP network is unstable, i.e. the QoS repeats increase and decrease after exceeding the second threshold but fails to be maintained for a predetermined time after exceeding the third threshold completely, the QoS monitor/controller does not send the seamless hand-off recovery command even though the QoS of the IP network exceeds the threshold.

The controller of the selector having received the seamless hand-off recovery command transfers a seamless hand-off recovery trigger/initiation message to the CSM and MSM chipsets (S121) .

Accordingly, the CSM and MSM chipsets hand off the CDMA phone from the CDMA network to the RF unit of the adaptive gateway (S122) . Namely, the CSM and MSM chipsets switch the communication path so that the voice signal of the CDMA phone is received by the RF unit of the adaptive gateway. And, the packetizer/depacketizer is enabled, thereby transferring a 8kbps CDMA signal received from the CDMA phone to the IP network.

Once the hand-off recovery toward the IP network is completed (S123) , the controller of the selector transfers a seamless hand-off recovery completion message to the QoS monitor/controller. The QoS monitor/controller then drops the path toward the CDMA network to which the voice signal of the CDMA phone is transferred so far (S124) .

Thereafter, the QoS monitor/controller keeps monitoring the QoS of the IP network.

FIG. 5 illustrates a flowchart of a communication service control procedure according to a second embodiment of the present invention, in which a voice signal of a wireline phone is served via IP like VoIP (voice over IP) .

First of all, a wireline phone is basically registered to an adaptive gateway (S200) . If the registered wireline phone makes a voice signal transmission request toward an IP network (S201) , a wireline communication channel is established (S202) . The wireline phone transmits a 64kbps PCM signal via the established wireline communication channel (S203) , and a vocoder of an adaptive controller converts the received 64kbps PCM signal to an 8kbps CDMA signal (S204) . A packetizer/depacketizer converts the 8kbps CDMA signal outputted from the vocoder to IP packet according to a transmission standard of the IP network and then transfers the IP packet to the IP network (S205, S206) .

A QoS monitor/controller monitors QoS of the IP network from a time point that the wireline communication channel for the wireline phone is established (S207) .

If the QoS of the IP network keeps being lowered after being lowered below a first threshold set up for determining hand-off execution (S208) , the QoS monitor/controller sends a seamless hand-off command to a controller of a selector and a controller of an adaptive controller (S209) .

In this case, the communication path of the wireline phone maintains the IP network. Namely, the controller of the adaptive controller opens a new output path toward an

RF unit side while maintaining the previous output path toward the IP network.

The controller of the selector transfers a seamless hand-off trigger/initiation message to CSM and MSM chipsets (S210) .

The MSM chipset operates like the CDMA phone tries a voice calling so that the wireline phone is handed off to the CDMA network, thereby carrying out call initiation/setup toward the CDMA network (S211) .

Once the call setup of the wireline phone to the CDMA network is successfully completed (S212) , the CSM and MSM chipsets carry out hand-off toward the CDMA network to hand off the wireline phone to the CDMA network (S213) . Namely, the CSM and MSM chipsets switch the communication path so that the voice signal of the wireline phone is received by BTS of the CDMA network. In this case, the voice signal of the wireline phone is firstly converted to an 8kbps CDMA signal .

Once hand-off for the wireless phone is completed

(S214) , the controller of the selector transfers a seamless hand-off completion message to both of the adaptive controller and the QoS monitor/controller (S215) .

As the seamless hand-off completion message is inputted, the QoS monitor/controller drops the communication path toward the IP network (S216) . And, the controller of the adaptive controller drops the output path to the IP network side of the second vocoder.

Yet, the QoS monitor/controller keeps monitoring the QoS of the IP network afterward (S217) .

If the QoS of the IP network, which becomes more satisfactory, keeps increasing to exceed a third threshold after exceeding a second threshold set up for determining hand-off execution (S218) , the QoS monitor/controller sends a seamless hand-off recovery command to the controller of the selector and the controller of the adaptive controller (S219) .

In this case, the communication path of the wireline phone maintains the CDMA network. Namely, the controller of the adaptive controller opens a new output path to the previous IP network side while maintaining the output path to the RF unit side of the second vocoder.

And, the QoS monitor/controller enables a packetizer/depacketizer and regenerates a path of the wireline toward the IP network (S220) . Thus, the communication paths of the wireline phone are simultaneously established to both of the CDMA and IP networks .

The controller of the selector having received the seamless hand-off recovery command transfers a seamless hand-off recovery trigger/initiation message to the CSM and MSM chipsets (S221) .

Accordingly, the CSM and MSM chipsets switch the communication path of the wireline phone to the IP network from the CDMA network (S222) and the MSM chipset releases a previously set call of the wireline phone (s223) .

Once the hand-off recovery toward the IP network is completed (S224) , the controller of the selector transfers a seamless hand-off recovery completion message to the QoS monitor/controller and the controller of the adaptive controller (S225) . And, the controller of the adaptive controller drops the output path toward the RF unit side of the second vocoder. Thereafter, the QoS monitor/controller keeps monitoring the QoS of the IP network.

INDUSTRIAL APPLICABILITY

Accordingly, the present invention hands off the voice signal of the terminal to the wireless network

(especially, CDMA network) in accordance with the QoS

(quality of service) of the wireline network (especially,

IP network) , thereby enabling to provide a high quality voice communication service in communication environments where wireless and wireline networks interwork.

And, the present invention enables to overcome the limitation of the VoIP service as well as maintains the advantages of the related art VoIP service.

Moreover, if the wireless and wireline networks are CDMA and IP networks, respectively, the present invention converts the 64kbps PCM signal to the 8kbps CDMA signal to transfer to the IP network, thereby enabling to reduce the use rate of the bandwidth 1/8 less than that of the related art in which the 64kbps PCM signal is packetized to transfer to the IP network.

Furthermore, the application of the wireless terminal is vocoded to 64kbps in the related art wireless network (specifically, the vocoder of BSC performs vocoding) . Yet, in the present invention, the application (voice or data) vocoded to 8kbps in the wireless terminal bypasses the vocoder to transfer to the network directly. Therefore, the present invention enables to reduce a probability that the transmission rate decreases as well as the bandwidth use rate.

Besides, the present invention can be flexibly applied to other wireless and wireline networks.

While the present invention has been described and illustrated herein with reference to the preferred embodiments thereof, it will be apparent to those skilled in the art that various modifications and variations can be made therein without departing from the spirit and scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention that come within the scope of the appended claims and their equivalents.

Claims

WHAT IS CLAIMED IS:

1. In a communication system having wireline and wireless networks interwork reciprocally, a method of controlling communication service, comprising: a first step of transferring a voice signal received from a terminal to the wireline network; and a second step of switching a communication path of the terminal to the wireless network in accordance of QoS (quality of service) of the wireline network.

2. The method of claim 1, wherein the first step is carried out in a manner that the voice signal received from a wireline terminal is converted to a signal according to a transmission standard of the wireless network to transfer to the wireline network.

3. The method of claim 1, further comprising the step of restoring the communication path of the terminal to the wireline network from the wireless network as the QoS of the wireline network is recovered to a communication service available level.

4. In a communication system having IP (Internet protocol) and CDMA networks interwork reciprocally, a method of controlling communication service, comprising: a first step of transferring a voice signal received from a CDMA phone to the IP network; a second step of monitoring QoS (quality of service) of the IP network; and a third step of switching a communication path of the CDMA phone to the CDMA network in accordance of the QoS (quality of service) of the monitored IP network.

5. The method of claim 4, after the third step, further comprising the step of restoring the communication path of the CDMA phone to the IP network from the CDMA network as the QoS of the IP network is recovered to a communication service available level .

6. The method of claim 4, wherein the third step is carried out in a manner that the communication path of the CDMA phone to the IP network is maintained before the communication path of the CDMA phone is completely switched to the CDMA network.

7. In a communication system having IP (Internet protocol) and CDMA networks interwork reciprocally, a method of controlling communication service, comprising: a first step of transferring a voice signal received from a wireline phone to the IP network; a second step of monitoring QoS (quality of service) of the IP network; and a third step of switching a communication path of the wireline phone to the CDMA network in accordance of the QoS (quality of service) of the monitored IP network.

8. The method of claim 7, wherein the first step is carried out in a manner that the voice signal received from the wireline phone is converted to a CDMA signal according to a transmission standard of the CDMA network to transfer to the IP network.

9. The method of claim 8, wherein a 64kbps PCM signal received from the wireline phone is converted to an 8kbps

CDMA signal.

10. The method of claim 7, wherein after the third step, the voice signal received from the wireline phone is converted to a CDMA signal according to a transmission standard of the CDMA network and the converted CDMA signal is transferred to the CDMA network.

11. The method of claim 7, after the third step, further comprising the step of restoring the communication path of the wireline phone to the IP network from the CDMA network as the QoS of the IP network is recovered to a communication service available level .

12. The method of claim 11, wherein the voice signal received from the wireline phone is converted to a CDMA signal according to a transmission standard of the CDMA network and the converted CDMA signal is transferred to the restored IP network.

13. In a communication system having wireline and wireless networks interwork reciprocally, a method of controlling communication service, comprising: a first step of checking an application received from a terminal; a second step of converting the received application to a packet according to a transmission standard of the wireline network; and a third step of transferring the converted packet to the wireline network.

14. The method of claim 13, wherein after the first step, if it is judged that the received application is received from a wireline terminal, the received application is converted to a signal according to a transmission standard of the wireless network.

15. The method of claim 14, wherein if it is judged that the received application is received from an analog wireline terminal, the received analog application is converted to a digital application and the converted digital application is converted to a signal according to the transmission standard of the wireless network.

16. In a communication system having IP (Internet protocol) and CDMA networks interwork reciprocally, a method of controlling communication service, comprising: a first step of judging whether an application is currently received from a CDMA phone or a wireline phone; a second step of converting the received application to a CDMA signal according to a transmission standard of the CDMA network if it is judged that the application is received from the wireline phone; and a third step of transferring the converted CDMA signal to the IP network.

17. The method of claim 16, wherein after the second step, the received application is directly transferred to the IP network if it is judged that the application is received from the CDMA phone .

18. The method of claim 16, the second step comprising the steps of: checking a characteristic and a transmission rate of the received application if it is judged that the application is received from the wireline phone; converting the received application to a PCM signal of a standardized transmission rate; and converting the PCM signal of the standardized transmission rate to the CDMA signal according to the transmission standard of the CDMA network.

19. The method of claim 16, wherein in the second step, an analog signal received from the wireline phone is converted to a 64kbps PCM signal and the converted 64kbps PCM signal is converted to an 8kbps CDMA signal.

20. The method of claim 16, wherein the second step is carried out in a manner that a 64kbps PCM signal received from the wireline phone is converted to an 8kbps CDMA signal .

21. A system for controlling communication service, comprising: a wireless terminal; a wireline terminal; and an adaptive gateway monitoring QoS (quality of service) of a wireline network to convert a communication path of the wireless or wireline terminal according to the QoS of the wireline network.

22. The system of claim 21, the adaptive gateway comprising: a QoS monitor/controller monitoring the QoS of the wireline network, the QoS monitor/controller commanding a communication path switch according to the QoS of the wireline network; and a selector switching the communication path of the wireless or wireline terminal to a wireless network according to a command of the QoS monitor/controller.

23. The system of claim 22, wherein the adaptive gateway further comprising a vocoder converting a voice signal of the wireline terminal to a signal according to a transmission standard of the wireless network.

24. The system of claim 22, wherein the selector carry out a call setup to the wireless network for the wireline terminal to switch the communication path of the wireline terminal to the wireless network.

25. The system of claim 22, wherein the adaptive gateway switches the communication path of the wireless or wireline terminal to the wireless network if the QoS of the wireline network becomes a communication service unavailable level and wherein the communication path of the wireless or wireline terminal is restored to the wireless network if the QoS of the wireline network becomes a communication service available level after the communication path is switched to the wireless network.

26. A system for controlling communication service, comprising: a wireless terminal following a transmission standard of a wireless network; a wireline terminal following a different transmission standard from the transmission standard of the wireless network; and an adaptive gateway transferring each application of the wireless and wireline terminals to one wireline network.

27. The system of claim 26, the adaptive gateway comprising a vocoder converting the application of the wireline terminal to a signal having a rate according to the transmission standard of the wireless network, the vocoder bypassing the application of the wireless terminal.

28. The system of claim 27, wherein the vocoder converts a digital application, which is converted from the application of an analog wireless terminal by a first converter or is inputted from a digital wireline terminal, to the signal having the rate according to the transmission standard of the wireless network.

29. In a communication service based on VoIP to an IP (Internet protocol) network, a communication service control system comprising: a CDMA phone; a wireline phone; and an adaptive gateway converting a voice signal of the CDMA or wireline phone to an IP packet to transfer to the IP network, the adaptive gateway monitoring QoS (quality of service) of the IP network to switch a communication path of the CDMA or wireline phone according to the QoS of the IP network.

30. The communication service control system of claim

29, wherein the adaptive gateway includes a vocoder bypassing the voice signal of the CDMA phone and converting the voice signal of the wireline phone to a CDMA signal according to a transmission standard of a CDMA network.

31. The communication service control system of claim

30, wherein the vocoder converts a PCM signal of a random transmission rate received from the wireline phone to an

8*X kbps PCM signal (where X is a natural number) and converts the converted 8*X kbps PCM signal to an 8*Y kbps CDMA signal (where Y is a natural number) following the transmission standard of the CDMA network.

32. The communication service control system of claim 30, wherein the vocoder converts a 64kbps PCM signal received from the wireline phone to an 8kbps CDMA signal following the transmission standard of the CDMA network.

33. The communication service control system of claim 30, wherein the vocoder converts a PCM signal of a random transmission rate received from the wireline phone to a 64kbps PCM signal and converts the converted 64kbps PCM signal to an 8kbps CDMA signal following the transmission standard of the CDMA network.

34. The communication service control system of claim 29, the adaptive gateway comprising: a QoS monitor/controller monitoring the QoS of the IP network, the QoS monitor/controller commanding a communication path switch according to the QoS of the IP network; a selector switching the communication path of the

CDMA or wireline phone to a CDMA network according to a command of the QoS monitor/controller; and a vocoder converting a voice signal received from the wireline phone to a CDMA signal following a transmission standard of the CDMA network.

35. The communication service control system of claim 34, the selector comprising:

CSM (cell site modem) and MSM (mobile system modem) chipsets switching the communication path of the CDMA or wireline phone to the CDMA network; and a controller receiving a communication path switch command of the QoS monitor/controller so that the CSM and MSM chipsets switch the communication path of the CDMA or wireline phone to the CDMA network.

36. The communication service control system of claim 35, wherein the selector and the QoS monitor/controller are constituted with one module.

37. The communication service control system of claim

35, wherein the MSM chipset carries out a call setup to the CDMA network for the wireline phone in order to switch the communication path of the wireline phone to the CDMA network.