KR20000045592A - Central control device of wireless local loop radio port - Google Patents

Abstract

PURPOSE: A central control device of wireless local loop(WLL) radio port is provided to reduce the cost of radio ports through blocking the increase of the number of link boards when shelves increase, by changing the structure of communication between the central control part and other processors from the parallel cell bus method to the series global bus method. CONSTITUTION: A central control device of wireless local loop(WLL) radio port includes five parts. A central processing part controls processing actions of the radio port control process unit and the protocol. A memory stores the program that is needed in the data and the interface processed in the central processing part. A SIO part executes the series communication between shelves in radio ports according to the control of the central processing part. A time switch makes the highway interface executed by highway switching of data by channels. A G-bus control part communicates in broadcasting method when communicated from the upper part to the lower part, and in point-to-point method when communicated from the lower part to the upper part.

Description

Central control unit of wireless subscriber network base station

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station in a wireless local loop (WLL). In particular, the structure of communication between the central control unit and other processors in a base station in a wireless subscriber network is changed from a parallel cell bus to a serial global bus. The present invention relates to a central control unit of a wireless subscriber network base station for reducing the cost of a base station by not increasing the number of link boards even if the shelf is increased.

In general, the WLL system has been developed in the 1990s, a narrowband CDMA system and a wideband CDMA system using a code division multiple access (CDMA) radio access standard. In order to meet the needs of subscribers through the advancement, high speed, wideband, and multimedia of existing communication networks worldwide, multimedia services such as voice, data, and video are transmitted at broadband and high speed using millimeter waves of 24-28GHz. Development of a two-way broadband WLL system is underway.

Therefore, WLL network components are largely divided into WLL exchanger, base station controller (RCP), base station (Radio Port, RP), subscriber interface (Radio Interface Unit, RIU), base station operating unit (Radio Port Operation). & Maintenance Center (RPOM), etc., and additionally, it consists of an inter-working function (IWF) and a home location register (HLR / AUC).

1 is a block diagram of a conventional wireless subscriber network base station.

Thus, in a conventional WLL system, a base station unit, RP, is a specific board called an asynchronous link control unit (ALCU), which provides internal interprocessor communication controller (IPC) communication functions and hernia information of each call control unit (CCU) board. The data was collected and transmitted to RPC, which is a control unit, using internal IPC communication, and the status information was collected by a line control unit (LCU).

2 is a diagram illustrating a rack configuration of a conventional base station.

Therefore, in the conventional base station system, in order for the control shelf and the channel shelf to perform IPC communication, ALCU1, 2 and LCU1, 2 must be relayed. This is because the cell bus method cannot communicate when the distance is a little shorter.

3 is a block diagram of a central control unit (RCP) of a conventional base station.

As shown therein, a central processing unit 11 for controlling overall interface operations of the central control unit; A memory (12) for storing data processed by the central processing unit (11) and a program required for an interface; A serial input output (SIO) unit 13 for performing serial communication between shelves in a base station under the control of the central processing unit 11; A time switch (14) for performing a highway interface by highway switching data for each channel under the control of the central processing unit (11); Under the control of the central processing unit 11, it is composed of a cell bus interface unit 15 for communicating with other blocks in the base station in parallel cell bus.

As described above, in the conventional wireless subscriber network system, a 32-bit parallel bus (10Mbps × 32 =) receives an ATM (Asynchronous Transfer Mode) cell as an inter-processor communication (IPC) between the base station and the base station controller. 320 Mbps) and bus arbitration by attaching routing headers to ATM cells.

4 is a view showing the structure of the cell bus in FIG.

The cell bus here is 37 parallel buses with 32 bits of data. Each cell placed on a cell bus by a CUBIT device can be routed to one single CUBIT or multiple CUBIT devices.

Since the cell bus system is a shared bus, it can be configured from a single board to a multi-board system using a back board. Since multiple CUBITs share the same bus, there is a possibility of a bus access collision problem, so leave an Arbitration Board.

So if CUBIT requires bus access, CUBIT 15 grants access in response. The CUBIT 15, which has been granted bus access, sends the cell to the bus. Any connected CUBITs 15 will receive this cell. The CUBIT (15) receiving the cell sends the control cell to the bus. CUBIT that initiates the loopback control cell from the bus receives this control cell.

However, the conventional device configured and operated as described above has a problem in that the cost of the system increases as an additional link board is required for IPC communication between shelves when the capacity is increased.

In addition, the conventional cell bus has a problem in that error data cannot be corrected because error checking is not performed between shelves as a parallel communication method.

Accordingly, the present invention has been proposed to solve the conventional problems as described above, and an object of the present invention is to provide a global system of serial communication in a parallel cell-bus system in a structure of communication between a central controller in a base station and another processor in a wireless subscriber network. The present invention provides a central control apparatus for a wireless subscriber network base station that can reduce the cost of a base station by changing the bus type so that the number of link boards does not increase even if the shelf increases.

In order to achieve the above object, the central control apparatus of the wireless subscriber network base station according to the present invention,

A central processing unit which controls overall call processing and protocol processing operations of the central control apparatus; A memory for storing a program required for interfacing with the data processed by the central processing unit; An SIO unit performing serial communication between shelves in a base station under control of the central processing unit; A time switch for performing a highway interface by highway switching data for each channel under the control of the central processing unit; Under the control of the central processing unit, the transmission and reception data and the clock are separated and communicated, and when transmitting from the upper to the lower by the broadcasting method, and transmitting from the lower to the upper point to the point to communicate The G-bus control unit is characterized by its technical configuration.

1 is a block diagram of a conventional wireless subscriber network base station,

2 is a view showing a rack configuration of a conventional wireless subscriber network base station,

3 is a block diagram of a central control apparatus of a conventional wireless subscriber network base station,

4 is a view showing the structure of the cell bus in FIG.

5 is a block diagram of a wireless subscriber network base station according to the present invention;

6 is a diagram illustrating a rack configuration of a wireless subscriber station base station applied according to the present invention;

7 is a block diagram of a central control device of a wireless subscriber network base station according to the present invention;

FIG. 8 is a block diagram illustrating a redundant structure of the G-bus controller in FIG. 7.

<Explanation of symbols for main parts of drawing>

21: central processing unit 22: memory

23: SIO unit 24: time switch

25: G-bus control unit

Hereinafter, with reference to the accompanying drawings an embodiment according to the technical idea of the central control apparatus of the present invention, the wireless subscriber network base station as described above in detail.

First, the present invention changes the inter-shelf bus structure (IPC) of the base station to a G-bus (Global bus) structure in order to solve the conventional problems as described above. It is a bus structure with a high-level data link control (HDLC) transmission format of the RS-485 standard, and has a data rate of up to 8Mbps. The improved G-bus structure enables communication without increasing the number of link boards even when the shelf is extended, thereby reducing the base station cost.

Figure 5 is a block diagram of a wireless subscriber network base station applied by the present invention, Figure 6 is a view showing a rack configuration of the wireless subscriber network base station applied by the present invention.

Thus, Figure 5 is a central control unit (RCP), which is a master board for arbitration, and E1-RPC, which is a slave board receiving a reference signal from the central control unit and acquiring bus occupancy rights in a sequential round robin manner and transmitting data. Consists of CCU boards. Thus, as shown in Figure 6 it is possible to expand up to 32 boards by simply connecting the cable without the relay board to the RCP. The reason for having two central control units (RCP) is to consider redundancy.

7 is a block diagram of a central control apparatus of a wireless subscriber network base station according to the present invention, and FIG. 8 is a block diagram showing a redundant structure of a G-bus controller in FIG.

As shown therein, a central processing unit 21 for controlling overall call processing and protocol processing operations of the central control apparatus; A memory (22) for storing data processed by the central processing unit (21) and a program required for an interface; A serial input output (SIO) unit 23 for performing serial communication between shelves in a base station under the control of the central processing unit 21; A time switch 24 for performing a highway interface by switching data on a channel-by-channel basis under the control of the central processing unit 21; Under the control of the central processing unit 21, the transmission and reception data and the clock are separated and communicated, and the transmission from the upper to the lower by the broadcasting (Broadcasting) method, and the transmission from the lower to the upper point-to- It is composed of a G-bus control unit 25 that communicates in a -point manner.

The G-bus control unit 25 includes a direct memory access (DMA) unit 31 which directly accesses a memory in the board during IPC communication with an external board; An HDLC unit 32 for controlling the HDLC frame; A D-bus controller 33 for controlling the operation of the D-bus; A G-bus controller 34 for controlling a duplex operation of the G-bus; A plurality of HIPC-NBC nodes connected to the HDLC unit 32 and controlling buffers for high quality IPC communication under the control of the D-bus and G-bus control units 33 and 34. Buffer Control) 35 to 37; A plurality of first in first out (FIFO) units 38 to 40 which temporarily store data of the plurality of HIPC-NBC units 35 to 37, respectively; A D-bus interface unit 41 for allowing the plurality of HIPC-NBC units 35 to 37 to interface with the D-buses; RS-485 transmission and reception unit 42 and 43 to perform the data transmission and reception of the RS-485 method through the G-bus.

Therefore, the central control unit (RCP) is a device in charge of all call processing functions and protocols in the base station, and has a time switch 24 so as to interconnect voice and data of subscribers. Since there is one time switch 24, a total of 2048 × 2048 (512 subscribers) can be processed, and IPC communication is performed through the G-bus.

The data transmission procedure from lower to upper is as follows.

First, in FIG. 8, the normal bus by loopback is detected for the G-buses A and B. FIG. If there is data to be transmitted, the RTS (Request To Send) signal, which is a transmission request signal, is driven.

In addition, after counting by its own ID, when the transmission turn comes, a CTS (Clear To Send) signal is generated to allow data transmission.

In addition to generating the CTS signal, the GAST signal for informing the other processor of the G-bus occupation is driven, and when the central processing unit 21 recognizes the CTS interrupt, data transmission is started.

When the data transfer is complete, the RTS signal is disabled, and after disabling the RTS signal, the GAST signal is disabled in order to transfer the bus share to another processor.

When the data to be transmitted next is generated, the RTS is driven and then waited.

Meanwhile, data transmission from upper to lower is performed as follows.

If it is not a cable hernia for the initial G-bus, receive it via G-bus A. Monitor GAST signals for G-buses A and B. Therefore, when GAST is driven low, it is determined that data is received from a lower level on the received bus. And start receiving data from the bus.

At this time, when the GAST signal is generated on both A and B buses, the central processing unit 21 generates a G-bus error interrupt, and continues to receive data on the first side of the GAST signals of the A and B buses.

If the bus occupies more than the specified length while receiving data from the lower CCU or E1-RPC, the upper central control unit (RCP) sends a G-bus error interrupt to the central processing unit 21 by the Long Assert Fault (LAF). Generate.

Data transmission from the central control unit (RCP) to the lower level is transmitted to all lower levels regardless of bus occupancy rights, and it is determined whether the data received from lower level is received.

As such, the present invention changes the structure of the communication between the central control unit and the other processors in the base station in the wireless subscriber network from the parallel cell bus method to the serial global bus method so that the number of link boards does not increase. .

Although the preferred embodiment of the present invention has been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

As described above, the central control unit of the wireless subscriber network base station according to the present invention performs the transmission / reception error and data error check using the G-bus, the error data can be retransmitted, the shelf is increased Even if the number of link boards does not increase, the cost of the base station can be reduced.

Claims (2)

In the central control apparatus of the wireless subscriber network base station, A central processing unit which controls overall call processing and protocol processing operations of the central control apparatus; A memory for storing a program required for interfacing with the data processed by the central processing unit; A serial input output (SIO) unit for performing serial communication between shelves in a base station under control of the central processing unit; A time switch for performing a highway interface by highway switching data for each channel under the control of the central processing unit; Under the control of the central processing unit, the transmission and reception data and the clock are separated and communicated, and when transmitting from the upper to the lower by the broadcasting method, and transmitting from the lower to the upper point to the point to communicate Central control apparatus for a wireless subscriber network base station, characterized in that the G-bus control unit. The method of claim 1, wherein the G-bus control unit, A direct memory access (DMA) unit for directly accessing memory in the board during IPC communication with an external board; An HDLC unit for controlling a high-level data link control (HDLC) frame; A D-bus controller for controlling the operation of the D-bus; A G-bus controller for controlling a duplex operation of the G-bus; A plurality of HIPC-NBC (High performance IPC-Node Buffer Control) units connected to the HDLC unit and controlling a buffer for high quality IPC communication under the control of the D-bus and G-bus controllers; A plurality of first in first out (FIFO) sections for temporarily storing data of the plurality of HIPC-NBC sections; A D-bus interface unit configured to interface the plurality of HIPC-NBC units with a D-bus; Central control device of a wireless subscriber network base station, characterized in that the RS-485 transmission and reception unit configured to perform the data transmission and reception of the RS-485 method through the G-bus.