KR20000065981A - ATM multiplexing /demultiplexing device in base station controller - Google Patents

Abstract

PURPOSE: A device for multiplexing/demultiplexing an asynchronous transfer mode(ATM) cell of a base station, is provided to multiplex an ATM cell transmitted from the base station and transmit the ATM cell to an ATM switch to be switched by destinations, and to demultiplex the switched ATM cell to be transmitted by destinations, thereby a control station has a transmission function of ATM cells from many base stations, so as to transmit every kind of traffic through an ATM network. CONSTITUTION: When an asynchronous transfer mode(ATM) cell is received from a base station(BS), the received cell is divided into an ATM adaptation layer(AAL)2-type ATM cell loading voice data and an AAL5-type ATM cell loading non-voice data, by four ATM frame/deframe assembly(AFDA,21a-21d) of a BTS interface subsystem(BIS). Then the ATM cells passe an ATM multiplexing/demultiplexing circuit(AMDA)(22) and are transmitted to an ATM switch(30), then are transmitted to MSC(50). The AMDA(22) has four AFDA(21a-21d), a controller, a cell bus interface, an ATM cell multiplexer/demultiplexer, a user-network interface(UNI), an optical transceiver and an external device monitoring circuit. The controller controls an entire operation for multiplexing/demultiplexing ATM cells between ATM switches. The cell bus interface performs an ATM cell bus interface function, and transceives the AFDA(21a-21d) and ATM cells. The ATM cell multiplexer/demultiplexer multiplexes the ATM cells from the cell bus interface and demultiplexes the ATM cells from the UNI, according to control of the controller. The UNI performs an ATM physical layer function and a STM-1 frame configuration function. The optical transceiver converts a serial electrical signal transmitted from the UNI into an optical signal, and reversely converts an optical signal from the ATM switch into an electrical signal. And the external device monitoring circuit monitors the mounting/demounting and operation of the AFDA(21a-21d).

Description

ATM multiplexing / demultiplexing device in base station controller

The present invention relates to an International Mobile Telecommunications System (IMT-2000), and more particularly, to an ATM (Asynchronous Transfer Mode) switch and an ATM frame / deframe device of a control station. By implementing the function of multiplexing / demultiplexing ATM cells between assemblies (AFDA) in hardware, the ATM method can be applied to a control station to provide a common network from narrowband service to broadband service. The present invention relates to an AT cell multiplexing / demultiplexing apparatus of a control station.

In general, the IMT-2000 system is developed to provide users with free mobility around the world. The IMT-2000 system is a broadband service such as data and voice, and broadband service such as video telephony, video conferencing, and high-speed data transmission. Integrates into terminals and provides multimedia and intelligent services for various media. In order to transmit all kinds of traffic using one common communication network, IMT-2000 system adopts ATM network as a backbone.

Therefore, a function of multiplexing / demultiplexing ATM cells between the ATM switch of the control station and the base station is required.

Accordingly, the present invention has been proposed for the ATM cell multiplexing / demultiplexing function in the control station required by adopting the ATM network as the backbone of the IMT-2000 system. By implementing hardware that implements frame / deframe (ATM) frame / deframe assembly (AFDA) and ATM multiplexing / demultiplexing ATM cells between ATM switches, the control station can implement ATM cells from the base station. After multiplexing, it transmits to the ATM switch, demultiplexes the ATM cells from the ATM switch, and then transmits them to the corresponding base station, thereby providing the narrowband and broadband services through a common ATM network. Disclosed is a TEM multiplexing / demultiplexing apparatus.

In order to achieve the above object, the AMT cell multiplexing / demultiplexing apparatus of the control station according to the present invention,

ATM switch for switching between four ATM Frame / Deframe Assemblies (AFDAs) in the control station and the ATM cells in the control station received from the base station performing wireless communication with the terminal in the IMT-2000 system Implemented between, multiplexing / demultiplexing ATM cells. The ATM multiplexing / demultiplexing assembly (AMDA),

A control unit controlling overall operation of a multiplexing / demultiplexing function for an ATM cell between the four AFDA and the ATM switch; A cell bus interface unit performing an ATM cell bus matching function to transmit and receive the AFDA and the ATM cells; An ATM cell multiplexer / demultiplexer for multiplexing ATM cells from the cell bus interface unit and demultiplexing ATM cells from a redundant UNI unit under control of the controller; A redundant user-network interface (UN) for performing an ATM physical layer function on the ATM cell from the ATM cell multiplexing / demultiplexing unit and performing an STM-1 frame configuration function; A redundant optical transceiver which performs a function of converting an electrical signal transmitted from the redundant UNI unit into an optical signal and inversely converts an optical signal from the ATM switch into an electrical signal; It is characterized by the technical configuration of the external device monitoring unit for monitoring the mounting / hernia state and the operation state of the plurality of AFDA.

The controller may include: a CPU for controlling the overall operation of the controller for the AMD cell multiplexing / demultiplexing function by the AMDA; A reset unit generating a control signal to the CPU when power is turned on or a push switch is operated; A clock generator providing a clock source to the controller; A flash ROM capable of mounting an operating system (OS) of the CPU; An Ethernet matching unit (ethernet) for interfacing with a network manager under a control of the CPU; RS232C matching unit for matching with RS232C under the control of the CPU.

1 is a block diagram of a control station to which the present invention is applied;

2 is a block diagram of an ATM cell multiplexing / demultiplexing apparatus of a control station according to the present invention;

3 is a block diagram of a control unit of FIG. 2;

4A is a flash ROM block diagram of FIG. 3;

4B is a block diagram of the Ethernet matching unit of FIG. 3;

4C is a boolean EPROM block diagram;

5 is a block diagram of a cell bus interface unit;

<Description of the code | symbol about the principal part of drawing>

21a-21d: AFDA 22: AMDA

30: ATM switch 61: control unit

62: Cellbus interface unit 63: ATM cell multiplexing / demultiplexing unit

64, 65: UNI part 66, 67: Optical transmitter and receiver

68: external device monitoring unit

Hereinafter, a detailed description will be given of the AMT cell multiplexing / demultiplexing apparatus of the present invention as described above.

1 is a block diagram of a control station to which the present invention is applied.

As shown in the figure, a base station matching subsystem (BTS Interface Subsystem; BIS) 20 for matching a base station 10 and a control station to perform wireless communication directly with a terminal in an IMT-2000 system; An ATM switch (30) which performs a switching function on the ATM cell transmitted from the base station matching subsystem (20); It consists of an ATM Multipliexing / demultipliexing Subsystem (AMS) 40 that matches between the ATM switch 30 and the switching center (MSC) 50.

As shown in FIG. 2, the BIS 20 divides an ATM cell transmitted from the BS 10 into an AAL2 type ATM cell and an AAL5 type ATM cell, respectively. Devices (ATM Frame / Deframe Assembly (AFDA) 21a-21d); Multiplex the ATM cells transmitted from the four AFDAs 21a-21d and transmit them to the ATM switch 30, and demultiplex the ATM cells transmitted from the ATM switch 30 to the four AFDAs 21a-21d. ATM ATM multiplexing / demultiplexing assembly (AMDA) 22 for transmission.

Thus, when an ATM cell is received from the base station (BS) 10, the receiving cell is transmitted by four AFDAs 21a-21d of the BIS 20 to an AAL2-type ATM cell carrying voice data and an AAL5 ATM carrying non-voice data. Are separated into cells. The ATM cell is then sent via the AMDA 22 to the ATM switch 30 and then to the MSC 50.

Referring to the configuration of the AMDA 22 according to the present invention, the AMDA 22 controls the overall operation of the multiplexing / demultiplexing function for the ATM cells between the four AFDA 21a-d and the ATM switch. A control unit 61; A cell bus interface 62 which performs an ATM cell bus matching function and transmits and receives an ATM cell with the AFDA (21a-21d); ATM cell multiplexing / demultiplexing unit 63 for multiplexing ATM cells from the cell bus interface unit 62 and demultiplexing ATM cells from the UNI units 64 and 65 under the control of the control unit 61. Wow; A user-network interface (UN) 64, 65 that performs an ATM physical layer function and performs an STM-1 frame configuration function; An optical transceiver for performing a function of converting a serial electric signal transmitted from the UNI units 64 and 65 into an optical signal and converting the optical signal from the ATM switch 30 into an electrical signal ( 66) 67; And an external device monitoring unit 68 for monitoring the mounting / dismounting state and the operating state of the AFDA 21a-21d.

Referring to the operation of each device of the AMDA 22 according to the present invention configured as described above are as follows.

The cell bus interface 62 is a device for a parallel bus in a shelf, and performs an inter processor communication (IPC) function, and is implemented in an ATM cell method. Each board is assigned a Virtual Path Identifier / Virtual Channel Identifier (VPI / VCI) and provides an interface for transmitting OAM cells and control signals. In the same shelf, 32 bits are transmitted and received in parallel and between shelves are sent and received in series. The cell bus interface 62 is controlled by the CPU 61a of the controller 61 as shown in FIG.

The control unit 61 multiplexes the ATM cells received through the cell bus interface unit 62 as described above and transmits the multiplexed ATM cells to the ATM switch 30, and demultiplexes the ATM cells from the ATM switch 30 to provide AFDA 21a-21d. To control the overall operation of the AMDA 22.

As shown in FIG. 2, the configuration of the control unit 61 includes a CPU 61a in which the AMDA 22 controls the overall operation of the control unit 61 for the ATM cell multiplexing / demultiplexing function; A reset unit 61b which generates a control signal to the CPU 61a and operates it manually when power is turned on or a push switch is operated; A clock generator 61c for providing a clock source to the controller 61; A flash ROM 61d capable of mounting an operating system (OS) of the CPU 61a; An Ethernet matching unit 61f for interfacing with a network manager under the control of the CPU 61a; An RS232C matching section 61j for matching with RS232C under the control of the CPU 61a.

The CPU 61a implements the MPC860SAR-50 to perform a control function so that the AMDA 22 can perform the ATM cell multiplexing / demultiplexing function.

The flash ROM 61d may mount an OS as shown in FIG. 4A and update the flash ROM 61d to a new OS in a board running state when necessary. AMD's four AM29F016B-90EC (2M * 8bit) with 8M byte capacity, 32bit data width and 5.0V simplify system level power requirements. The device guarantees a minimum of 100,000 write / erase cycles and supports locking and erase using 32 sectors in 64KB increments. This speeds up the processing speed of the CPU 61a.

The Ethernet matching unit 61f is a module for interface with a network manager, and includes an encoder and a LAN matching unit, as shown in FIG. 4B, and controls the CPU 61a. According to the matching function. The encoder is implemented by MOTOROLA's MC68160QFP to receive and operate a 20 MHz clock source from the clock generator 61c, and the LAN matching unit is used for 10BASE-T.

A bootable EPROM (Erasable and Programmable Read Only Memory) (not shown in FIG. 3) is as shown in FIG. 4C and is used for initial board initialization after the CPU 61a reads the reset configuration word. So / CS0 is used. The boot EPROM is implemented with four or two AMD AM27040-12 (512K * 8bit) devices.

The / HRESET of the reset unit 61b operates the CPU 61a at power on using a TTL (Transistor-Transistor Logic) element or manually by using a push switch. In addition, / SRESET operates the CPU 61a when the power is turned on by using the TTL element or manually by using a push switch.

The ATM cell multiplexing / demultiplexing unit 63 multiplexes the ATM cells transmitted from the cell bus interface unit 62 and transmits the multiplexed ATM cells to the UNI unit 64 under the control of the control unit 61 as described above. A 4: 1 multiplexer / demultiplexer is used to support four AFDAs 21a-21d. Up to 8: 1 multiplexing / demultiplexing can be performed. It also performs ATM physical layer / ATM layer and UTOPIA (Universal Test and Operations Physical Interface for ATM) I, II interface functions. The bandwidth is 622Mbps for burst data transmission and 160Mbps for full duplex transmission.

The ATM cell multiplexing / demultiplexing unit 63 multiplexes the ATM cells transmitted from the cell bus interface unit 62 under the control of the control unit 61 as described above, and transmits the multiplexed ATM cells to the UNI units 64 and 65. The ATM cells from the UNI units 64 and 65 are demultiplexed and transmitted to the AFDAs 21a to 21d via the cell bus interface unit 62.

The AMDA 22 implements the UNI unit 64, 65 and the optical transceiver 66, 67 in a dual manner to operate in a load sharing manner. Thus, the load is not biased on either side, but the two UNI units 64 and 65 and the two optical transceivers 66 and 67 are operated with the same load, and multiplexed to the ATM switch 30, respectively. The transmitted ATM cell. In addition, the ATM cells switched in the ATM switch 30 are demultiplexed to the ATM cell multiplexing / demultiplexing unit 63 through the optical transceivers 66 and 67 and the UNI units 64 and 65.

Referring to the operation of the UNI unit 64, 65, the UNI unit 64, 65 performs the ATM Forum 155Mbps physical layer function, and between the cell bus interface 62 and the optical transceiver 66, 67 STM-1 (Synchronous Transfer Mode-1) performs frame composition, cell delineation, and clock recovery. In more detail, the UNI units 64 and 65 perform UTOPIA Level 1 interface functions, perform STM-1 framer / reframer and overhead processing functions, and perform optical transceivers 66 and 67. Converts the parallel data from the serial data into the serial data, and converts the serial data into the parallel data and transmits the data to the optical transceiver 66 (67).

The optical transceivers 66 and 67 convert the direct currency (DC) electrical signals received from the UNI units 64 and 65 into optical signals, transmit the optical signals to the ATM switch 30, and perform the reverse function. Perform physical layer PMD (Physical Medium) function.

In addition, the external device monitoring unit 68 monitors the status of a fan, a power supply unit, and the like that are not directly mounted on a cell bus, which is a shelf backplane, and four AFDAs 21a- mounted on the backplane. 21d) monitors the hernia / mounting state, operation state, and the like to notify the controller 61.

The AMDA 22 which multiplexes / demultiplexes the ATM cells between the four AFDAs 21a to 21d and the ATM switch 30 is implemented to enable ATM cell transmission at the control station. Therefore, in IMT-2000 system, ATM network is used as a lower network to provide narrowband services such as low speed data transmission and telephone and broadband services such as video telephony, video conferencing and high speed data transmission.

As described above, the AT cell multiplexing / demultiplexing apparatus of the control station according to the present invention is a hardware device for performing a function of multiplexing / demultiplexing an ATM cell between an ATM Frame / Deframe Assembly (AFDA) and an ATM switch. As a result, the control station multiplexes ATM cells from multiple base stations and transmits them to the ATM switch, and demultiplexes the ATM cells switched from the ATM switch to the corresponding base station. Therefore, all kinds of traffic such as narrowband service and broadband service can be transmitted through ATM network.

Claims (3)

In the IMT-2000 system, an ATM (Asynchronous Trnasfer Mode) cell transmitted from a base station performing wireless communication with a terminal is divided into an ATM Adaptation Layer 2 (AAL2) type ATM cell and an AAL5 type ATM cell. In the IMT-2000 control station comprising four ATM Frame / Deframe Assembly (AFDA) for each function to perform the function, and an ATM switch for performing the ATM cell switching function, ATM multiplexing / demultiplexing assembly for multiplexing and transmitting the ATM cells transmitted from the AFDA to the ATM switch and demultiplexing the ATM cells switched in the ATM switch for each destination and transmitting them to the respective AFDAs An AMD cell multiplexing / demultiplexing apparatus of a control station, characterized in that it comprises: AMDA). The method of claim 1, wherein the AMDA, A control unit controlling overall operation of a multiplexing / demultiplexing function for an ATM cell between the four AFDA and the ATM switch; A cell bus interface unit performing an ATM cell bus matching function to transmit and receive the AFDA and the ATM cells; An ATM cell multiplexer / demultiplexer for multiplexing ATM cells from the cell bus interface unit and demultiplexing ATM cells from a redundant UNI unit under control of the controller; A redundant user-network interface (UN) for performing an ATM physical layer function on the ATM cell from the ATM cell multiplexing / demultiplexing unit and performing an STM-1 frame configuration function; A redundant optical transceiver which performs a function of converting an electrical signal transmitted from the redundant UNI unit into an optical signal and inversely converts an optical signal from the ATM switch into an electrical signal; An AT cell multiplexing / demultiplexing apparatus of a control station, comprising: an external device monitoring unit configured to monitor mounting / mounting states and operating states of the plurality of AFDAs. The method of claim 2, wherein the control unit, A CPU for the AMDA to control the overall operation of the controller for the ATM cell multiplexing / demultiplexing function; A reset unit generating a control signal to the CPU when power is turned on or a push switch is operated; A clock generator providing a clock source to the controller; A flash ROM capable of mounting an operating system (OS) of the CPU; An Ethernet matching unit (ethernet) for interfacing with a network manager under a control of the CPU; And a RS232C matching unit for matching with RS232C according to the control of the CPU.