KR100290427B1 - Method for tracing/controlling channel destination of pager satellite transmission system - Google Patents

Abstract

PURPOSE: A method for tracing/controlling a channel destination of a pager satellite transmission system is provided to previously prevent that a service is stopped by the quality degradation of a dedicated line by tracing/controlling monitoring and control information of a central office in a remote station. CONSTITUTION: A channel connection alarm of a demultiplexer is cleared in a state in which a communication is disconnected with a central office, and it is confirmed whether a channel connection failure alarm is generated. States of a remote station demodulator and the demultiplexer are checked when generating the channel connection failure alarm. If the remote station demodulator and the demultiplexer are normally operated, a source/the first destination channel field in which a connection error is generated from a remote station channel destination seen from a central office is calculated. The second destination channel field is calculated from a channel destination seen from a remote station to the central office. The calculated source channel field is compared with the calculated second destination channel field. If the calculated source channel field is different from the calculated second destination channel field, the second destination channel field is replaced with the source channel field and a central office channel destination seen from the remote station is changed for performing a subscriber server in a state in which a communication is disconnected with the central office.

Description

Channel destination tracking / control method of radio calling satellite transmission system

The present invention relates to a radio calling satellite transmission system (also called "PagerSat"), and in particular, communication between the central station and the base station is reduced due to deterioration of the quality of the dedicated line by tracking and controlling the monitoring and control (M & C) information of the central station in the base station. The present invention relates to a channel destination tracking / control method of a radio calling satellite transmission system which prevents the interruption of radio calling service under a broken situation.

A general radio call data satellite transmission system (PagerSat) is shown in FIG. 1.

Here, reference numeral 1 denotes a wireless call exchanger, reference numeral 2 denotes an exchange channel card connection unit to which the wireless call exchanger 1 and a channel card are connected, and reference numeral 3 denotes a network manager system.

Further, reference numeral 4 denotes a central station controller which is responsible for overall control of radio call transmission while interfacing data with the network manager system 3, and reference numeral 5 denotes while interfacing data with the central station controller 4; A multiplexer which multiplexes the radio call data transmitted from the exchange channel card connection unit 2.

Reference numeral 6 denotes a modulator for modulating the radio call data multiplexed by the multiplexer 6, and reference numeral 7 denotes a transmitter for transmitting the radio call data modulated by the modulator 6 to the satellite.

In addition, reference numeral 8 is a satellite for receiving the radio call data transmitted from the transmitter 7 and transmitting the received radio call data to the terminal station, and reference numeral 9 is a radio call transmitted from the satellite 8. Receiving unit for receiving data, reference numeral 10 is a demodulation unit for demodulating the radio call data received by the receiving unit 9 to the original data.

Reference numeral 11 denotes a terminal station controller for controlling the entire operation of the terminal station, and reference numeral 12 demultiplexes the radio call data demodulated by the demodulation unit 10 under the control of the terminal station controller 11. The demultiplexer 13 is a transmitter channel card connection unit for transmitting the demultiplexed radio call data from the demultiplexer 12 to the transmitter 14.

Reference numeral 15 serves to interface a dedicated line data communication between the central station controller 4 and the terminal station controller 11 to a center PCCB.

The general radio call data satellite transmission system configured as described above processes call data by the following operation.

That is, the switch channel card connection unit 2 (PCIB: Paging Central Interface Block) converts the FSK analog paging signal, which is the radio call data output from the radio call exchanger 1 (TDX-PS), into digital data and multiplexer 5 ).

The Quad Synchronous Processor (QSP) in the multiplexer 5 carries the multiplexed data (64Kbps, 128Kbps) into the corresponding time slot of the multiplexed data (600bps, 1200bps, 2400bps). Will be done.

At this time, the network control unit 5c (Local Paging Central Control Block) performs the overall control on the multiplexing, and the multiplexed radio call data is transmitted to the modulation unit (ILC: Intermachine Link Module). 6) is delivered.

Here, look at the main functions of each part in more detail as follows.

The QSP is composed of four synchronous data channels, and compensates for the clock synchronization of channel input and output data and the deviation between the system clock and the received clock. The QSP is connected to the PCIB and RS-232 and is redundant. .

In addition, the ILC multiplexes data and voice and focuses frames.

The NCL, the network control unit, defines the programming parameters, initiates diagnostic test and outputs diagnostic test results, initializes channel access and requests for channel release, displays the dynamic system and module status of all accessible nodes, and detects all alarm conditions. It is responsible for reporting to the highest user terminal, selecting system clock sources and controlling network clocking configurations, storing system databases, and controlling redundancy of NCL and ILC modules.

On the other hand, the modulator 6 modulates the input digital radio call multiplexed data at a high frequency and amplifies the power, and transmits the modulated radio call data to the transmitter 7 so as to be transmitted to the satellite 8.

That is, the modulator 6 performs CCITT V.35 scrambling, differential coding, R = 1/2 K = 7 convolutional coding, and BPSK modulation on the baseband signal (64 Kbps / 128 Kbps) input from the multiplexer 5. An IF signal having a bandwidth of 250 KHz / 500 KHz in an intermediate frequency (IF) band of 52 MHz to 88 MHz is transmitted to the transmitter 7.

The transmitter 7 transmits the transmitted RF to the satellite 8 to be transmitted to the base station.

That is, the transmitter 7 adjusts uplink power by the UPCU and the beacon receiver, and the power-controlled transmission signal is transmitted to the outdoors by the UPRC which performs the redundancy control, and is distributed by the outdoor power divider to transmit the transmitter. Is passed to. In the transmitter, the signal of the outdoor transmitter, which is amplified at a predetermined uplink frequency and power level, selected by the waveguide switch, is connected to the feeding part of the antenna by the OMT, and radio waves are emitted to the satellite 8. The beacon signal transmitted from the satellite 8 is received by the beacon receiver through the antenna and the LNB, and used for uplink power control and antenna tracking control.

In addition, the satellite 8 receives the radio call data transmitted from the transmitter 7 as described above, and then retransmits it to the terminal station side, the receiving unit 9 of the terminal station side receives it to the demodulator 10 Deliver it.

The demodulator 10 then demodulates the received multiplexed radio call data into original data, i.e., BPSK demodulation, Descrambling, differential decoding, R = 1/2 K = 7 beaters The original data is restored by non-decoding, and the demodulated multiplexed radio call data is demultiplexed by the demultiplexer 12 and transmitted to the transmitter 14 through the transmitter channel card connection 13 as a low-speed radio call data. Transmitted and delivered to the subscriber.

Here, the interlink card (ILC) in the demultiplexer 12 serves to demultiplex the multiplexed data of the central station in the same way as the interlink card in the central station, and is composed of non-redundancy.

In addition, the PCCB provided in the central station responsible for monitoring and controlling the central station and the base station is composed of a local PCCB and a master PCCB, where the local PCCB is the NCL of the central station multiplexer, the PMIB of the modulation unit, the antenna controller of the RF unit, and the beacon receiver. It is in charge of the uplink power controller, transmitter controller A / B, the outside, and the Master PCCB is a central station controller 4 to poll the Local PCCB and the Center PCCB 15 to the center and base station devices. It reports the status to the network management unit 3: NMS, reports the status message, and also distributes the commands of the NMS to each device.

The Center PCCB 15 is a device for communication between the central station and the base station. When the Master PCCB polls the Center PCCB 15, the Center PCCB 15 reports the base station status message collected through the PRCB to the Master PCCB. It consists of Center PCCB board, modem card, self, back board and power supply. In addition, 16 self-modem cards can be mounted. Here, each modem card is connected to each base station by a dedicated line to transmit / receive data.

Next, the network management system (NMS), which manages the overall configuration and state of the radio call satellite transmission system, adjusts the components of the central station multiplexer, modulator output frequency adjustment, RF unit transmission output control, The terminal provides the user with a GUI control function such as center station control such as antenna orientation angle adjustment, demultiplexer component control, and demodulator reception channel frequency adjustment. The NMS device uses a workstation and provides a serial port that can be connected to a PCCB. In addition to network monitoring and control functions, the program can flexibly cope with site diversity and expansion of a radio calling satellite transmission system. This is made up.

The general radio call data satellite transmission system which operates in this way duplicates the central station (to the main and spare center stations) to improve the reliability, and the data between the central station and the base station interface with each other through a dedicated line.

The multiplexing equipment used in the general radio calling satellite transmission system is logically designated as the channel destination, and when the channel destination between the central station and the base station is misaligned, the connection is boiled and the service is stopped on the channel card.

The master PCCB, which is the central station control unit, changes the channel destination to change the primary / preliminary of the multiplexer channel card when the central station channel card switching request generated at the base station satisfies a specific condition. At this time, the changed channel destination is transmitted from the central station through the master PCCB and the center PCCB through the leased line to the base station controller PRCB. The PRCB interprets this information (QSP switching accept message) and connects with the channel of the central station multiplexer channel card. It is calculated and set whether this should be done.

However, in such a general radio call satellite transmission system, when the dedicated line or other equipment fails and communication between the central station and the base station is interrupted, the base station does not receive channel destination change information due to the redundant switching of the central station multiplexer channel card. This caused a problem that became impossible.

Accordingly, the present invention has been proposed to solve various problems occurring in the general radio calling satellite transmission system as described above.

The present invention tracks and controls the monitoring and control (M & C) information of the central station in the base station. The radio call satellite transmission prevents the service from being interrupted when the communication between the central station and the base station is lost due to the degradation of the dedicated line. The purpose is to provide a channel destination tracking / control method of the system.

Method according to the present invention for achieving the above object,

A first step of clearing a channel access alarm of the demultiplexer and confirming that a channel access failure alarm occurs in a state where communication with the central station is lost;

A second step of checking a state of a base station demodulator and a demultiplexer when the channel access failure alarm occurs and calculating a source / first destination channel field in which a connection error occurs from a base station channel destination viewed from a central station if the channel access demodulator and the demultiplexer are operating normally;

A third step of calculating a second destination channel field from the channel destination viewed from the base station by the base station after the second step;

If the calculated source channel field and the calculated second destination channel field are different from each other, the second station channel field is replaced with the source channel field, and then the central station channel destination viewed from the base station is changed to cut off communication with the central station. It is characterized in that the fourth step to make the wireless call service even in the state.

In the above, if the channel access failure alarm does not occur in a state where communication with the central station is lost, it is determined that the channel access is normally performed, and the destination tracking / control is not performed.

The destination tracking / control may not be performed in a state where a failure occurs in a base station demodulator in a state where a channel access failure alarm occurs or in a service output state of a demultiplexer.

If the source channel field calculated in the second step and the second destination channel field are identical to each other, the destination tracking / control is not performed.

1 is a block diagram of a general radio calling satellite transmission system;

2 is a procedure showing a multiplexer channel card switching process of a radio call satellite transmission system in the present invention;

3 is a control flowchart illustrating a channel destination tracking / control method of a radio call satellite transmission system according to the present invention;

<Explanation of symbols for main parts of the drawings>

1: Wireless call exchanger 2: Exchange channel card connection

3: network management system 4: central station control unit

5: Multiplexer 11: Terminal station controller

12: Demultiplexer 15: Center PCCB

Hereinafter, described in detail with reference to the accompanying drawings, preferred embodiments of the present invention.

Since the radio call satellite transmission system to which the present invention is applied is the same as the general radio call satellite transmission system shown in FIG. 1, its configuration and operation are omitted.

2 is a diagram illustrating a multiplexer channel card redundancy switching procedure for explaining multiplexer channel destination tracking / control.

This will be described with reference to FIG. 1.

In general, the channel card of the multiplexing station of the central station multiplexing system of the radio calling satellite transmission system does not detect the failure of the hardware in the NCL, which is the control unit of the multiplexing unit. Use a specific signal called a T-pattern.

The T-pattern signal is generated at the subscriber access unit (PCIB) of the central station, and when the transmission data of the TDX-PS is not transmitted, the ASCII "t" is transmitted to the multiplexer every 5 seconds and multiplexed. This multiplexed signal is a modulator. It is transmitted to a base station via a high frequency transmitter, an antenna, and a satellite.

In the base station, the T-pattern is retrieved from the transmitter connection subscriber access unit (PRIB) via an antenna, a low noise amplifier (LNB), a demodulator, and a demultiplexer (DEMUX). If this T-pattern is not detected in PRIB for a certain time, a T-pattern alarm is triggered.

The base station network management unit (PRCB) periodically polls the base station subscriber access unit (PRIB), interprets the current state of the PRIB (channels and power supplies), updates the buffers, and prevents unnecessary central station multiplexer channel card duplication. If the center PCCB polls the status of the base station, the QSP switching request is transmitted first.

Next, the master PCCB analyzes the information collected from the PRCB, detects a QSP switching request message, and calculates a channel number slot number of a failed central station multiplexer by calculating (always an odd value).

The calculated slot number and the hardware ID obtained by polling the central station multiplexer (DSP ST SY) and the information on the DB ID (DSP ST SY ACK) are compared / analyzed (in this case, the calculated hardware ID and DB ID are present. Change the slot number), calculate the slot number of the currently failed channel card, and poll the multiplexer to determine if at least one channel of the four channel card ports of the slot is connected (DSP CON) and respond (DSP CON ACK). Analyze and confirm.

Count the number of QSP switching request base stations that require redundancy switching for the specific channel card of the central station multiplexer that has failed, and compare whether the counting value is greater than or equal to the QSP switching threshold downloaded from the network management system (NMS). At this time, if the number of base stations where the QSP switching request occurs is larger than the QSP switching dress and the QSP switching mode of the master PCCB is enabled (initial value is disabled and is determined to be enabled / disabled by the NMS), the QSP switching starts with the NMS. The message is reported, and the QSP switching accept message (slot number to be activated by the central station multiplexer channel card duplication switch) is transmitted to all base stations through the leased line at once.

The DB of each of the four ports of the failed multiplexer channel card is polled (DSP CH), read (DSP CH ACK), and copied to the spare channel card (DEF CH / QSP).

Next, delete the DB of the failed central station multiplexer channel card (DEL SL, SL: Slot Number). At this time, channel is disconnected and DB is deleted.

A channel connection (CON CH) is performed to each of the four ports of the reserved channel card of the central station multiplexer newly created in the DB so that the changed channel destination is valid at the base station. At this time, the channel destination tracking / control algorithm of the base station should be connected after maintaining a certain time necessary for completion. From this point, the spare channel card becomes the main channel card to provide the clock to the PCIB, and the radio call service, which was interrupted by the channel card duplication changeover, resumes.

If the channel connection is established normally (DSP CON ACK), the QMS switching complete message is transmitted to the NMS.

In this way, during the communication using the dedicated line between the central station and the base station, the central station multiplexing unit is in a state where communication with the central station is lost due to a failure of the dedicated line or other monitoring and control communication devices (on average, 10 to 20%). When the channel card is duplexed and switched, the PRCB, which is the base station controller, cannot receive the QSP switching accept message and the radio call service is stopped.

In order to solve this problem, the present invention performs the algorithm as shown in FIG. 3 so that the wireless call service can be performed even when communication between the central station and the base station is lost.

That is, as shown in Fig. 3, it is checked whether there is a polling message of the center PCCB for a predetermined time to confirm the communication state with the central station.

In this case, if there is a polling message, communication with the central station is normally performed. Therefore, check whether there is a QSP switching accept message. If there is a QSP switching accept message, the central station redundantly switches the multiplexer channel card. Therefore, the channel destination number is analyzed by analyzing the QSP switching accept message (including the slot number to be activated by the central station multiplexer channel card duplication switchover). Calculate

Next, after polling the demultiplexer (DSP CH) to read the DB of each of the four channel card ports (DSP CH ACK), the channel destination is reset by inserting the calculated channel destination number into a specific field (DEF CH / QSP). do.

On the other hand, as a result of checking whether the QSP switching accept message is present, if there is no QSP switching accept message, the central station does not duplicate the multiplexer channel card and terminates the channel destination tracking / control procedure.

If there is no polling message, since communication with the central station is lost, the QSP switching accept message cannot be received and the channel destination of the central station multiplexer channel card is tracked / controlled as follows.

That is, the channel connection failure alarm (Alarm 12) of the demultiplexer is cleared (DSP ST ALM 12 / C) and the channel connection failure alarm (alarm 12) is checked (DSP ST ALM 12 ACK). If the check result indicates that there is no alarm 12, the channel connection is normally established. Therefore, the procedure for tracking / controlling the channel destination is terminated.

Unlike the above, when the alarm 12 occurs, the channel connection is not normally performed, so the channel destination tracking / control procedure is performed.

That is, when the demodulator is in the fault state or the demultiplexer is in the service output state by checking the state of the demodulator and the demultiplexer, which are the base station demodulator, the channel destination tracking / control is not performed because the channel destination does not have meaning.

When the demodulator is in a normal state and the demultiplexer is not in a service output state, the source / first destination channel field where a connection error occurs is obtained from a base station channel destination (DSP DST DL "2" ACK) viewed from the central station. Where "2" is the base station demultiplexer interlink card slot number, and this information is stored in the DB of the central station multiplexer and the base station multiplexer channel destination change is tracked by the base station because the update information is transmitted to the base station whenever the channel destination is changed. This is possible.

Next, the second destination channel field is obtained from the channel destination (DSP DST CH ACK) viewed from the base station by the base station. Where "CH" is the destination channel calculated above.

Thereafter, the calculated source channel field and the second destination channel field are compared with each other, and if they are the same, an alarm 12 does not occur due to a mismatch between channel destinations, thereby terminating a channel destination tracking / control procedure. If the second destination channel field is different, the second destination channel field is replaced with the source channel field, and the central station channel destination viewed from the base station is changed (DEF CH / QSP).

By performing the channel destination tracking / control procedure as described above, even if the communication between the central station and the base station is interrupted due to a failure in the dedicated line or other monitoring and control equipment, the base station tracks / controls the channel destination information of the multiplexer channel card in the multiplexer channel card. Redundant switching is possible, and the interruption of the wireless call service is prevented.

As described above, the present invention periodically checks the communication status between the central station and the base station in the base station, and if the communication with the central station is lost due to a failure of the dedicated line or other equipment, periodically polls the demultiplexer and the central station multiplexing unit. By monitoring the channel destination of the de-multiplexer of the base station as seen in the above, it is possible to track / control the channel destination changed according to the channel card duplication change of the central station multiplexer. There is an effect that can be prevented in advance.

In addition, the above effects enable manual and automatic switching of the central station multiplexer channel card regardless of the failure of the dedicated line or central station monitoring and control equipment, thereby greatly improving the performance and reliability of the radio calling satellite transmission system. There is an advantage to this.

Claims (4)

In the radio call data satellite transmission system for transmitting radio call data through a satellite, A first step of clearing a channel access alarm of the demultiplexer and confirming that a channel access failure alarm occurs in a state where communication with the central station is lost; A second step of checking a state of a base station demodulator and a demultiplexer when the channel access failure alarm occurs and calculating a source / first destination channel field in which a connection error occurs from a base station channel destination viewed from a central station if the channel access demodulator and the demultiplexer are operating normally; A third step of calculating a second destination channel field from a channel destination viewed from the base station by the base station after the second step; If the calculated source channel field and the calculated second destination channel field are different from each other, the second destination channel field is replaced with the source channel field, and then the central station channel destination viewed from the base station is changed and communication with the central station is lost. Channel destination tracking / control method of a radio calling satellite transmission system, characterized in that the fourth step to make the subscriber service even in the state. 2. The method of claim 1, wherein if the channel access failure alarm does not occur in a state where communication with the central station is lost, it is determined that the channel connection is normally performed and the destination tracking / control is not performed. How to track / control channel destinations. The channel destination of the radio call satellite transmission system according to claim 1, wherein the destination tracking / control is not performed if a failure occurs in the base station demodulator in the state where the channel access failure alarm occurs or the demultiplexer outputs the service. Tracking / Control Method. The system of claim 1, wherein the destination tracking / control is not performed if the source channel field calculated in the second step and the second destination channel field calculated in the third step are the same. How to track / control channel destinations.

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