KR20020056764A - Method for cnnecting asynchrouns transfer mode in mobile communication system - Google Patents

Abstract

PURPOSE: An ATM(Asynchronous Transfer Mode) connection mode in a mobile communication system is provided to set an ATM connection between a traffic channel and SDU in subsystem of each terminal end through a PVC(Permanent Virtual Circuit), and apply an SVC(Switched Virtual Circuit) at an ATM network switch. CONSTITUTION: A base station(10) includes a base station control unit(16). A base station router(11) routes the ATM packet of the base station. A base station interface unit(12) performs a link connection between a control station(20) and the base station(10) through E1,T1 or STM-1 grade. A base station shelf control unit(13) controls a digital shelf of the base station(10). Channel cards(14,15) receive the packet traffic information from an exchange in order to transmit audio and data information from the base station(10) to a mobile station, then synchronize the signal to match a wireless frame, process the signal for expanding the band, and insert control information if necessary.

Description

Method for cnnecting asynchrouns transfer mode in mobile communication system}

The present invention relates to an Asynchronous Transfer Mode (ATM) connection method in a mobile communication system. In particular, an ATM connection between a traffic channel and an SDU is set as a fixed virtual link (PVC) in a subsystem of each end, and switching is performed in an ATM network switch. The present invention relates to an asynchronous transmission mode connection method in a mobile communication system that is adapted to efficiently connect an ATM by applying a virtual link (SVC).

In the ATM, the age of multimedia, which integrates conventional media such as voice, video, and data, is rapidly expanding, and communication using text and video and information retrieval services such as electronic libraries / art galleries have already become commonplace through the Internet. Research is underway for the practical use of broadcasting services such as (VIDEO ON DEMAND), and services such as telemedicine or distance education.

In this era of change, the expectation of a network providing multimedia communication services is also increasing. Next-generation networks not only differentiate the form of communication from voice to multimedia, but also create various new cultural forms and industries. It is also easy to see that we will realize a rich life. Under these expectations, the movement to build a broadband network at a high speed, which is incomparable with the conventional telephone network, is being actively conducted in advanced countries.

Although the current network is individually configured in a manner appropriate to each media, in order to provide a multimedia communication service, it is necessary to provide each media communication in one network, and each media has different communication characteristics for each media. It must be satisfied. For example, it must be able to flexibly cope with the communication speed, required quality and media characteristics of each media.

A network for achieving this purpose may be referred to as a high-speed broadband network (B-ISDN), and the information transmission method used in this context is based on the development of high-speed high-capacity communication technologies such as optical fiber communication technology and highly integrated circuit technology. It was born with ATM (Asynchronous Transfer Mode) technology.

The CDMA mobile communication system is evolving into synchronous IMT-2000 through digital cellular network (DCN) and personal mobile communication (PCS) services, and standardization of protocols that can support it is also progressing through the IS-2000 series and inter-operability of wireless sections. It is evolving beyond specification 3G IOS V4.0. The 3G IOS standard recommends the ATM protocol for fast and efficient transport of user traffic in packet environments. Table 1 shows a signaling connection transport protocol and a user connection connection transport protocol between a base station and an A3 interface or a control station and an A7 interface.

signaling connection (A3, A7) user traffic connection (A3) IOS ApplicationTCPIPAAL5ATMPhysical Layer user traffic frameSSSARAAL2ATMPhysical Layer

Accordingly, packet transmission and reception between the traffic channel of the base station and the SDU of the control station is performed by routing by the virtual path identifier / virtual channel identifier (hereinafter, abbreviated as VPI / VCI) of the ATM.

Hereinafter, with reference to the accompanying drawings will be described the operation of the base station and the control station network configuration and its function of a typical mobile communication system.

1 is a diagram illustrating a network configuration of a base station and a control station in a general mobile communication system.

The base station 10 includes a base station controller 16 for controlling the base station, a base station router 11 for routing ATM packets of the base station, and an E1, T1 or STM-1 class between the control station 20 and the base station 10. A base station link matching unit 12 serving as a link connection, a base station shelf control unit 13 for controlling a digital shelf of the base station, and channel cards 14 and 15.

In this case, the channel cards 14 and 15 receive packetized traffic information from the switching center to transmit the voice and data information from the base station 10 to the mobile station (not shown) to synchronize and spread the band according to the radio frame. It performs signal processing and inserts control information when necessary. In addition, it demodulates the signal received from the mobile station, performs necessary signal processing, and forms a packet to transmit to the switching center. In addition, the channel card is interfaced with the cell control unit and has a function of exchanging control information related to call setup, call release, and handoff.

The control station 20 is a control station control unit 21 for controlling the control station 20, and the control station that serves as a link connection of the E1, T1 or STM-1 class between the control station 20 and the base station 10 A link matching unit 27, a control station router 26 for routing ATM packets of the control station, a control station shelf control unit 22 for controlling the digital shelf of the control station, and SDUs 23, 24; Reference numeral 25 denotes a network controller for controlling the ATM connection at the control station 20.

ATM VPI / VCI, which is used when the actual subscriber call is established in the mobile communication system, is a switched virtual link (SVC), which uses ATM metasignaling or separate signaling for SVC configuration of the application. A resource allocated every hour and recovered when a call is released. It is assumed that the application controls the SVC connection. At this time, the VPI / VCI value assignment for the SVC is in charge of the network control unit 25 of the control station, and is transmitted to the control station control unit 21 and the base station control unit 16. At this time, the connection for transmitting the control message between processors is set as a permanent virtual link (PVC). Here, the path through which user traffic is transmitted / received between the base station channel and the control station SDU is determined by the user data received in the channel cards 14 and 15, the base station shelf control unit 13, the base station router 11, and the base station link matching unit 12. Through the control station link matching unit 27, the control station router 26, the network control unit 25 and the control station shelf control unit 22 to the SDU (23, 24).

Here, the control station control unit 21 directly transmits the VPI / VCI value of each section of the call to the base station shelf control unit 22, SDUs 23 and 24, the control station router 26, and the control station link matching unit 27. In other words, the processor indirectly forwarded and received performs the function for ATM connection.

The base station control unit 16 directly or indirectly sends the VPI / VCI value of each section of the call to the base station router 11, the base station link matching unit 12, the base station shelf control unit 13, and the channel card 14, 15, or the like. Passed and received processor performs the function for ATM connection.

After the ATM connection is established between the channel cards 14 and 15 between the SDUs 23 and 24, user traffic between the channel and the SDUs 23 and 24 is transmitted and received. At this time, since there is a need to go through the steps of establishing and verifying the ATM connection in several steps, the call setup flow becomes complicated, and call setup takes a long time and has a high probability of failure.

For example, each ATM component of the base station and the control station (base station shelf control unit and base station router of the base station, control station shelf control unit of the control station, network control unit and control station router) and channel for each call establishment and release including handoff. The procedure of establishing and releasing SVC connections to cards and SDUs introduces complexity in call flow, which increases the delay of call setup time and the possibility of failure of call setup and tear including handoff.

An object of the present invention is to solve the problems of the prior art, the ATM connection between the traffic channel and the SDU is set to a fixed virtual link (PVC) in the subsystem of each end, ATM network switch The present invention provides a method for asynchronous transmission mode connection in a mobile communication system that can efficiently switch ATM by applying a switching virtual link (SVC).

In the mobile communication system of the present invention for achieving the above object, the asynchronous transmission mode connection method includes the steps of calculating the maximum capacity of the subscriber according to the frequency capacity of the base station, and each call according to the calculated maximum capacity. Setting the asynchronous transmission mode connection to the first local PVC in the base station upon initializing the base station, calculating a maximum acceptable capacity according to the number of SDUs of the control station, and according to the calculated maximum acceptable capacity. Setting the asynchronous transmission mode connection for each call to a second local PVC in the control station upon initialization of the control station; and if any call occurs in either the base station or the SDU, each link of the base station and the control station Establishing the SVC connection between matching units.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

1 is a view showing a network configuration of a base station and a control station in a mobile communication system

* Description of the symbols for the main parts of the drawings *

10: base station 11: base station router

12: base station link matching unit 13: base station shelf control unit

14, 15: channel card 16: base station control unit

20 control station 21 control station control unit

22: control station shelf control unit 23, 24: SDU

25 network control unit 26 control station router

27: control station link matching unit

Hereinafter, a configuration and an operation according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

Asynchronous transmission mode connection method in the mobile communication system according to the present invention will be described with reference to the network configuration of the base station and the control station of the CDMA mobile communication system shown in FIG.

As described above with reference to FIG. 1, the base station 10 is a base station serving as a link connection of an E1, T1 or STM-1 level between the base station controller 16, the base station router 11, the control station 20, and the base station 10. The link matching section 12, the base station shelf control section 13, and the channel card (14, 15).

The control station 20 also controls the control station control unit 21, control station link matching unit 27, control station router 26, control station shelf control unit 22, SDUs 23 and 24, and network control unit 25. It consists of.

In general, the number of subscribers of the base station 10 is limited according to the frequency capacity. Therefore, the capacity of the base station 10 is calculated and the VPI / VCI value for each call corresponding to the total capacity is allocated during the initialization of the base station 10, so that the channel cards 14 and 15, the base station shelf control unit 13 and The ATM connection of the base station router 11 section is always set. In other words, it operates as a local PVC.

Local PVC here means that connections are always set to the same VPI / VCI values without any partial VPI / VCI conversions within a particular subsystem.

Likewise, in the control station 20, an acceptable capacity may be determined according to the number of SDU elements of the control station 20. Therefore, the VPI / VCI value of each call corresponding to the maximum capacity of the control station 20 is allocated at the time of initializing the control station 20 so that the SDUs 23 and 24, the control station shelf control unit 22 and the network control unit 25 section are allocated. Always maintains an ATM connection. In other words, it operates as a local PVC.

By doing so, the ATM connection setting for the section operated by the local PVC is omitted when the call is set up, and only the section between the base station 10 and the control station 20 from the base station router 11 to the network control unit 25 is SVC. You can set it up as a connection.

At this time, the base station router 11 and the base station link matching unit 12 of the base station 10 converts the virtual path identifier / virtual channel identifier value of the base station local PVC into the virtual path identifier / virtual channel identifier value of the SVC. The network controller 25, the control station router 26, and the control station link matching unit 27 of the control station 20 convert the virtual path identifier / virtual channel identifier value of the control station local PVC into the virtual path of the SVC. Used by converting to identifier / virtual channel identifier value.

In the ATM connection method, each call appears to be a PVC connection from the channel card (14, 15) and the SDU (14, 15), but from a real system network level, it is a pseudo SVC connection configured as an SVC connection.

As described above, the present invention operates an ATM connection (channel card, base station shelf control unit and base station router) in a base station subsystem as a local PVC, and provides an ATM connection (SDU, control station shelf control unit and network control unit) of the SDU subsystem in the control station. By operating the local PVC as a local PVC, the call flow can be simplified, thereby reducing the call setup time and reducing the possibility of call setup and release failure including handoff, thereby maintaining a more stable system.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (3)

Calculating a maximum acceptable capacity of the number of subscribers according to the frequency capacity of the base station; Setting the asynchronous transmission mode connection for each call to a first local PVC within the base station upon base station initialization according to the calculated maximum acceptable capacity; Calculating a maximum acceptable capacity according to the number of SDUs of the control station; Setting the asynchronous transmission mode connection for each call to a second local PVC within the control station upon initialization of the control station according to the estimated maximum acceptable capacity; And establishing a SVC connection between the link matching unit of each of the base station and the control station when a random call occurs in any one of the base station and the SDU. The method of claim 1, wherein the local PVC in the base station is set between the channel card, the base station shelf control unit and the base station router, and the local PVC is set between the SDU, the control station shelf control unit and the network control unit in the control station. Asynchronous transmission mode connection method in mobile communication system. The method of claim 1, wherein the step of setting the SVC between the link matching unit of each of the base station and the control station, Converting the virtual path identifier / virtual channel identifier value of the first local PVC into the virtual path identifier / virtual channel identifier value of the SVC in a base station router and a base station link matching unit of the base station; Converting the virtual path identifier / virtual channel identifier value of the second local PVC into the virtual path identifier / virtual channel identifier value of the SVC in a network control unit, a control station router and a control station link matching unit of the control station. Asynchronous transmission mode connection method in a mobile communication system, characterized in that made.