KR100605946B1 - atm interfacing appratus and method of base station controller in mobile communication system - Google Patents

Abstract

In a mobile communication system, an ATM interface device of a control station connected to an exchange station through a synchronous transmission mode interface, and connected to a base station via an E1-ATM interface, directly connected to a base station, sorts data in E1 format and generates various alarms. A plurality of E1 interface units for detecting, a plurality of ATM layer interface units for assembling data streams of an E1 format transmitted from the E1 interface into ATM cells, and conversely, decomposing an ATM cell into an E1 stream and delivering the E1 interface unit to the E1 interface unit; It consists of a multiplexing / demultiplexing unit for multiplexing the ATM cells transmitted from the ATM layer interface unit and transmitting them to another block, and distributing ATM cells inputted to the corresponding ATM layer interface unit.

IMT-2000, ATM, E1-ATM Interface

Description

Atm interfacing appratus and method of base station controller in mobile communication system             

1 is a block diagram of a communication system designed in a synchronous transmission mode according to the prior art.

2 is a block diagram of a mobile communication system according to the present invention;

3 is a block diagram of a control station for AMT interfacing according to an embodiment of the present invention;

The present invention relates to a mobile communication system, and more particularly, to an ATM interface device and a method of a base station controller (BSC).

1 is a diagram showing a communication system designed in a synchronous transfer mode (STM) according to the prior art.

Referring to FIG. 1, the E1 frame generator 111-11N transfers E1 frame data (PCM data) input through the E1 interface line to the time division switch 121. The time division switch 121 performs time division switching on the input PCM data and outputs the same to the corresponding port.

As shown in FIG. 1, the existing communication system transmits data input from each transmission line to another board or another system using a separate protocol using a time switch 121. That is, the existing mobile communication system is designed in a synchronous transmission mode (STM) method rather than an ATM structure, so that the data transmission efficiency is low, and it is inefficient to transmit a large amount of data irregularly.

However, the use of ATM in a mobile communication system enables the transmission of multimedia information such as data and video as well as voice-oriented services supported by existing cellular mobile communication networks with high speed data transmission and high bandwidth support.

Accordingly, an object of the present invention is to provide a mobile communication system using an asynchronous transmission mode (ATM).

Another object of the present invention is to provide a control station apparatus capable of interfacing an asynchronous transmission mode in a mobile communication system and a control method thereof.

In a mobile communication system for achieving the above objects, an ATM interface device of a control station connected to a switching center via a synchronous transmission mode interface, and connected to a base station via an E1-ATM interface, directly connected to a base station, and in data in E1 format. A plurality of E1 interface units for aligning and detecting various alarms, and assembling data streams of an E1 format transmitted from the E1 interface into ATM cells, and conversely, decomposing an ATM cell into an E1 stream and delivering them to the E1 interface unit. ATM layer interface unit and multiplexing / demultiplexing unit for multiplexing and transmitting ATM cells transmitted from the ATM layer interface unit to another block and distributing ATM cells to the corresponding ATM layer interface unit. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding the reference numerals to the components of each drawing, the same components have the same reference numerals as much as possible even if displayed on different drawings. In describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

2 is a block diagram of a mobile communication system using an asynchronous transmission mode according to the present invention.

Referring to FIG. 2, a base station (BTS) 212 processes a radio subscriber interface. The control station (BSC) 213 is located between the base station (BTS) 212 and the switching center (MSC) 214, and controls up to 64 base stations. In particular, the control station 213 performs functions such as location registration, service access, call and session control, real-time traffic processing, handoff processing, network management function, and switch matching of the mobile terminal. In addition, all data is exchanged between the control station 213 and the base station 212 and the network inside the control station 213 is exchanged by a BAN (Bsc Atm Network) configured as an ATM switch, and data transmission between the switching station 214 and the control station 213 is performed by STM. Is done in a way. Router 217 performs the routing function of the ATM cell. Global ATM Network (GAN) 215 is an ATM switch located between the router 217 and the base stations, provides a permanent virtual channel (PVC) and switched vertical channel (SVC) functions, and provides constant bit rate (CBR) and VBR ( It provides quality of service (QoS) such as variable bit rate) and unspecified bit rate (UBR), and performs network management functions such as traffic management, congestion control, and congestion avoidance. In particular, the GAN215 has a transmission line interface of DS-1E (2.048 Mbps) to match with the base station 212, UTP25 (25.6 Mbps), UTP155 (155.520 Mbps) for each unit interface in the control station 213 Provide an interface port. Base station manager (BSM) 216 provides a GUI () environment for operator network management tasks on a commercial workstation platform and manages control stations / base stations / ATM switches via SNMP (). . It also has TMN mediation device functionality for the NMC interface.

According to the above configuration, up to 64 base stations 213 processing the wireless subscriber interface are in charge of one control station 214, and the base station 212-control station 213 is connected to ATM-E1 / T1. The base station 212 has a 1.2 Gbps ATM switch capacity as a CellBus structure, and the control station 213 has a 5 Gbps ATM switch capacity. One switching station 214 manages up to 12 control stations 213, which control the Global ATM Network (GAN) 215 and ATM 155M or E1 / T1, which provide an inter-BSC soft handoff path between the control stations. Can be connected. The base station manager (BSM) 216, which manages the control station 213 and the GAN215, is connected to the GAN215 and the ATM 155M. It provides a path for soft handoff between exchanges.

In the above configuration, the ATM interface device of the control station 213 is shown in FIG.

Referring to FIG. 3, the E1 interface unit 311 includes a line interface unit LIU and an E1 frame generation unit E1 framer, and is directly connected to the base station through the E1-ATM interface. The E1 interface unit 311 performs a function of sorting data in E1 format and detecting various alarms. The ATM layer interface unit 312 receives the data stream in the E1 format from the E1 interface, assembles the cell into 53 byte cells, and conversely segments the ATM cell, and delivers the segment to the E1 interface unit 311 as an E1 stream. The multiplex / demultiplexer (MUX / DEMUX) 313 transmits 8x1 multiplexed 8x1 multiplexed to the corresponding block to transmit 8 ports E1-ATM input from the ATM layer interface 312 to one port, and vice versa. The signal input from the other block is demuxed to 1 × 8 and transmitted to the ATM layer interface unit 312. The control unit 315 controls various devices in the control station, and is particularly responsible for transmitting and receiving ATM cells. The interprocessor communication unit 314 is configured as a FIFO for exchanging various information between the processor in the board and the processor of the other block, and exchanges information in units of ATM cells. The clock receiver 319 receives a clock from the system and uses the clock clock as a transmission clock of the frame generator. The program memory 316 stores a program for controlling the overall operation of the control station. The program memory 316 may use a flash memory. The data memory 317 stores data parameters and the like generated during operation of the control station. The data memory 317 may use a RAM. The device control logic unit 318 selects and controls various input / output (I / O) devices on the board.

Looking at the operation according to the configuration of Figure 3 as follows.

The interface device provided in the control station is a board designed to transmit and receive data between the control station and the base station. The data transmission / reception standard is designed in the CEPT (E1) method. The bipolar signal input at a rate of 2048 Kbps through the transmission line is converted into a digital signal through the shaping circuit of the line interface unit (LIU). In addition, the line interface unit extracts clock and PCM data from a signal input through the transmission line, decodes the signal to HDB3 (High Density Bipolar 3), checks the bipolar error LOS (Loss Of Signal), and delivers the result to the E1 frame generator. Various alarm and error information detected here may be stored in a register inside the chip or notified to the controller through an external interrupt pin.

The E1 frame generator arranges the frames according to the E1 format, reports various frame-related alarm information, and transmits them to the ATM layer interface unit 312. Then, the ATM layer interface unit 312 assembles 30 channel data excluding time slots 0 and 16 into 53-byte ATM cells in the received E1 frame. That is, the ATM layer interface unit transfers the ATM cell to the E1 multiplexer 313 through a 4-cell FIFO, in which case the UOPIA (UTOPIA, Universal Test and Operation Physical Interface for ATM) connection protocol is followed.

The E1 multiplexer 313 multiplexes the ATM cells input from the eight ATM layer interface units 312 and the interprocessor communication unit 314 and transmits the multiplexed ATM cells. In this way, all nine ATM cells are multiplexed and transmitted to the other block, so that the transmission efficiency is improved, and the input port of the other block can be reduced from nine to one. In addition, the E1 demultiplexer 313 examines the VPI (Virtual Path Identifier) and the VCI (Virtual Channel Identifier) for the ATM cell received from the other block and corresponds to the corresponding ATM layer interface unit on a cell basis. 312 or the FIFO of the interprocessor communication unit 314. The cell transmitted to the ATM layer interface unit 312 is converted into an E1 stream and transmitted to the base station through the E1-ATM interface, and the cell transferred to the interprocessor communication unit 314 is read by the controller 315.

As described above, the control station according to the present invention has a structure in which transmission path data having a multiport is arranged and transmitted in units of ATM cells, and has a structure for transmitting a cell by multiplexing eight ATM layer interface units and a communication unit between processors; On the contrary, it is designed to demultiplex ATM cells transmitted from other blocks and transmit them to the corresponding ports, which greatly increases the efficiency of the system.

Claims (5)

In the AT interface device of the mobile radio control station, Directly connected to the base station, a plurality of E1 interface unit for sorting data in E1 format and detecting various alarms, A plurality of ATM layer interface units for assembling an E1 format data stream transmitted from the E1 interface into ATM cells, and conversely, decomposing an ATM cell into an E1 stream and delivering the same to the E1 interface unit; ATM of the mobile radio control station, comprising: multiplexing / demultiplexing unit for multiplexing and transmitting the ATM cells transmitted from the ATM layer interface unit to another block and distributing ATM cells inputted to the corresponding ATM layer interface unit Interface device. The method of claim 1, wherein the E1 interface unit, A line interface unit for converting an input bipolar signal into a digital signal, extracting a clock and PCM data, decoding the signal, and detecting an error; Atm interface device of a mobile radio control station characterized in that the PCM data arranged in a frame conforming to the E1 format and configured to report the various frame-related alarm information. The method of claim 1, ATM interface device of a mobile radio control station further comprises an interprocessor communication unit for transmitting and receiving various information between the processor in the board and the processor of the other block. In the ATM interfacing method of the control station, Sorting data received from the base station in E1 format and detecting various alarms; A cell assembly / decomposition process of assembling the data stream of the E1 format into an ATM cell, and decomposing the incoming ATM cell into an E1 stream; And a multiplexing / demultiplexing process of multiplexing the ATM cells and transmitting them to another block and distributing ATM cells inputted to the corresponding ATM layer interface unit. The method of claim 4, wherein the sorting of data received from the base station in an E1 format and detecting various alarms comprises: Converting an input bipolar signal into a digital signal, extracting a clock and PCM data, decoding and detecting an error; And aligning the PCM data into a frame conforming to the E1 format and reporting various frame-related alarm information.

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