KR19980027346A - How to reset data call in satellite communication system - Google Patents

Abstract

According to the present invention, when an abnormality occurs in a data call while a subscriber is using a reserved data call, the present invention automatically cancels the call and allocates a new available data call to minimize the communication failure. A method of resetting a data call in a system, the method comprising: a satellite communication system having a network management system in which a plurality of subscribers and a plurality of base stations are combined and are connected with a network control unit and an administrator to manage the system through satellites; When the base station communicates through a reserved data call, the base station continuously determines whether there is an error for the call, and when an error occurs, an error signal transmitting step of transmitting a predetermined error signal to the network control unit; An error signal retransmission step of retransmitting the error signal to the network management system when an error signal is received, and the network management system, when the error signal is input from the network control unit, a call release command for a data call in which this error has occurred. And a data call reassignment step of outputting a reassignment command for other available data calls.

Description

How to reset data call in satellite communication system

The present invention relates to a communication system using satellite, and in particular, when an abnormality occurs in a data call while a subscriber is using a reserved data call, the call is automatically released and a new available data call is allocated. The present invention relates to a method of resetting a data call in a satellite communication system that can minimize disturbances.

Recently, with the rapid development of communication technology, satellite communication, which enables subscribers who are located at remote sites to make calls through satellites, is becoming increasingly common. Such satellite communication is mainly used as a long distance communication between countries, or a communication method in a mountainous country such as Korea, because a separate signal line is not required for a call.

The satellite communication is a PAMA (Pre-Assignment Multiple Access) method for allocating a channel according to a channel allocation method that a subscriber wants to use in the future and a communication channel is allocated in real time according to a subscriber's request. It can be divided into two types of demand assignment multiple access (DAMA) method.

1 is a block diagram showing the overall system configuration of the satellite communication system according to the PAMA method.

In Figure 1, reference numeral 1 is a satellite having a plurality of communication channels, 2 is a central control station for controlling the entire satellite communication system, 3 (3A, 3B) is a data terminal and facsimile, such as an exchange, a telephone, a computer, etc. A base station having an interface function for a terminal and providing a call function between the various terminals through data transmission and reception with the central control station 2.

In FIG. 1, reference numeral S denotes a service channel for transmitting and receiving control data, and T denotes a traffic channel for transmitting and receiving data or voice.

In the above configuration, the central station 2 grasps the state of each base station 3 based on the response message transmitted from the base station 3 after transmitting the control message through the service channel S. . That is, a polling function for checking the available capacity of the base station 3 or the communication channel is performed.

On the other hand, the central control station (2) is associated with the data call (data call), such as the connection time and communication speed, such as the reservation time, subscriber number, synchronous or asynchronous, with a predetermined signal to reserve the satellite channel allocation by the operator When the information is input, the data call related information is stored, and when the reservation time is reached based on this data, the communication channel and the communication modem (SCU) are allocated to control the communication between the base stations.

Subsequently, when the end time of use of the channel set by the operator has elapsed, the central control station 2 executes a communication termination process for both base stations to release the traffic channel T provided for both base stations 3A and 3B. Done.

2 is a block diagram showing the configuration of the central control station 2 described above.

In FIG. 2, reference numeral 21 is an antenna for transmitting / receiving an satellite 1, an uplink signal, and a downlink signal, and 22 is an antenna 21 through the antenna 21 using a polarization property of frequency. Orthogonal Mode Transducer (OMT) for separating and transmitting and receiving signals, 23 is a low noise amplifier for low noise Low Noise Amplifier (LNA), 24 is a frequency down converter (DC) for converting a frequency signal applied through the low noise amplifier 23 into an intermediate frequency signal IF of 70 MHz, for example.

In addition, reference numeral 25 separates and outputs the intermediate frequency signal IF applied from the frequency down converter 24 into a plurality of intermediate frequency signals, and also describes a Single Channel Per Carrier (SCP) channel unit to be described later. IF C / D: IF Combiner / Distributer (IF C / D) for combining and outputting the intermediate frequency signal applied from the SCU: 26, and 26 is an intermediate frequency applied from this intermediate frequency combiner / distributer 25. It is a SCPC channel unit that demodulates, decodes and outputs a frequency signal, and encodes, modulates, and outputs a message output from the network controller 40 to be described later.

Here, the intermediate frequency combination / distribution unit 25 is employed for system scalability when using a plurality of SCPC channel units, and the SCPC channel units 26 are generally 32.

In addition, reference numeral 27 denotes a frequency up-converter for converting an IF signal of 70 MHz applied from the IF combination / distributor 25 into an microwave of 14.0 to 14.5 GHz to generate an uplink frequency signal. And 28 are high power amplifiers (HPAs) for amplifying uplink frequency signals output from the frequency up-converter 27.

Reference numeral 40 denotes a state of each base station 3 based on a response message transmitted from the base station after transmitting a control message to each base station 3 through an arbitrary SCPC channel unit 26 _{1 to} 26 _n . This is a network controller that performs polling function to check In addition, the network controller 40 allocates the available traffic channel T and modem when the channel allocation command according to the data call is input from the network management system 50 to be described later. System control such as communication can be performed.

Reference numeral 50 denotes a network management system for managing the overall network of the satellite communication system by managing the network control unit 40 through a man-machine interface which will be described later by a system administrator. The network management system 50 performs data call processing by outputting call setup and release signals to the network controller 40 based on data call information input by an administrator.

Next, the operation of the device having the above configuration will be described.

In a normal state, the network controller 40 of FIG. 2 performs a polling operation on each base station to check the state of the base station.

That is, after generating a message of the TDM stream from the packet data for checking the status of each base station of the network control unit 40 and outputs it to any SCPC channel unit 26.

Then, the corresponding SCPC channel unit 26 outputs an intermediate frequency signal by encoding and modulating the message, and the intermediate frequency signal is combined for each frequency in the IF combining / distributing unit 25, and then the frequency increasing converting unit. At 27, it is converted into an uplink frequency signal. The uplink frequency signal is output through the high power amplifier 28, the quadrature mode converter 22, and the antenna 21, and then transmitted to each base station 3 through the satellite 1 in FIG.

Meanwhile, the response message signal received from the base station 3 through the satellite 1 to the antenna 21 is applied to the frequency down converter 24 through the quadrature mode converter 22 and the low noise amplifier 23 and is applied to 70 MHz. It is converted into an intermediate frequency signal of and then applied to any SCPC channel unit 26 through the IF combination / distributor 25 to be demodulated and decoded and then applied to the network controller 40.

In addition, the network controller 40 extracts packet information from the received message, generates an S-ALOHA packet, and updates and registers a predetermined information storage unit based on this to hold state information for all base stations.

In addition, the above-described polling operation is continuously performed for each base station.

On the other hand, in general, the voice call is performed by the DAMA method, the data call is performed by the PAMA method, and the network controller 40 receives this information when the data call information is input from the network management system 50. PAMA data call processing is performed by allocating a communication channel and a communication modem to a corresponding subscriber based on a count time of a timer provided therein.

That is, when data related to a data call is input by the operator, the data is stored in a predetermined memory. Here, the data related to the data call is a reservation channel start time, end time, subscriber number, synchronous or asynchronous connection mode and communication speed.

Subsequently, when a predetermined result signal is input from a timer provided therein while the channel reservation time is in the future and the caller ID and the called party number are normally present, the data related to the data call is transferred to the network controller 40. Will print. Then, the network controller 40 transmits a call setup command to the corresponding base station based on the data call related data.

However, the subscriber may use the reserved data call during communication, for example, due to various reasons such as a malfunction of the call path, an error in the data line, or an error in the assigned communication modem. When the communication is not available, the communication can no longer be performed, and thus the disadvantage is that the administrator providing the system is disadvantaged because the reliability from the subscriber is lost.

Accordingly, the present invention has been made in view of the above circumstances, and when a data call being used becomes incapable of communication, it must be immediately replaced with another available call. In this case, the subscriber can be immediately released by disabling the communication call and quickly setting up another available call. The purpose of the present invention is to provide a data call resetting method in a satellite communication system that provides a continuous communication service.

1 is an overall system configuration for explaining the outline of a general satellite communication system.

FIG. 2 is a functional block diagram showing the configuration of the central control station 2 in FIG.

3 is a functional block diagram showing the configuration of a network management system 50 to which the present invention is applied.

4 is an operation flowchart for explaining a data call resetting method according to an embodiment of the present invention.

* Brief description of the main parts of the drawing

1: satellite 2: central control station

3A: base station 21: antenna

22: quadrature mode converter 23: low noise amplifier

24: Frequency down converter 25: Intermediate frequency combination / distribution unit

26: SCPC channel unit 27: frequency upconverter

28: high power amplifier 40: network control unit

50: network management system 51: processor

52: man-machine interface 53: terminal server

54: timer 55: base station information storage unit

56: data call information storage unit

In the satellite communication system according to the present invention for realizing the above object, a data call resetting method is a network management system in which a plurality of subscribers and a plurality of base stations are combined with a network control unit and a manager that manages it through satellites to manage system congestion A satellite communication system having a; When the base station communicates through a reserved data call, the base station continuously determines whether there is an error for the call, and when an error occurs, an error signal transmitting step of transmitting a predetermined error signal to the network control unit; An error signal retransmission step of retransmitting the error signal to the network management system when an error signal is received, and the network management system, when the error signal is input from the network control unit, a call release command for a data call in which this error has occurred. And a data call reassignment step of outputting a reassignment command for other available data calls.

Thus, according to the above, when any data call becomes incapable of communication, communication failure can be minimized by quickly replacing with another available data call.

Next, an embodiment according to the present invention will be described with reference to the accompanying drawings.

FIG. 3 is a block diagram illustrating a data call resetting method in a satellite communication system to which the present invention is applied. In FIG. 3, the same reference numerals are given to the same parts as in FIG. 2, and a detailed description thereof will be omitted.

In the drawing, reference numeral 51 denotes a processor for controlling the overall operation of the network management system 50, and 52 denotes an information exchange device between the satellite communication system and an operator for operating the same, that is, the operator can check the information from the system. A man-machine interface (MMI) comprising an output device and an input means for an operator to input a command for executing an operation of a satellite communication system.

In addition, reference numeral 53 denotes a terminal server for transmitting and receiving signals to and from the network control unit, which provides a communication protocol of RS-232C in communication with the network control unit, and 54 is a timer for counting a predetermined time. .

In addition, reference numeral 55 is a base station information storage unit for storing each state information such as communication channel of each base station and modem usage state input through the network control unit 40, and 56 is a channel reservation inputted by an administrator, for example. Data call information storage unit for storing data call related data including time, calling and called party number, communication speed, etc.

Next, a data call resetting method according to the present invention will be described with reference to the drawings.

First, while the data call is established and the subscriber is performing communication, the base station 3 in charge of the subscriber continuously searches the communication channel, communication modem, and channel state used by the subscriber to determine whether there is an error. .

Subsequently, when the base station 3 recognizes that an error has occurred in a communication modem, the base station 3 transmits a predetermined error signal including the communication modem number, the base station identification code, or the like, to the central control station 2. Bar network controller 40 of central control station 2 outputs this signal to network management system 50 in real time.

Subsequently, when the predetermined error signal is received from the network controller 40 (step ST1), the network management system 50 immediately outputs an error signal to the operator screen to the system administrator, thereby making the call available to the currently communicating subscriber. The abnormal state of the will be reported (ST2 step).

Subsequently, the network management system 50 transmits a predetermined call release signal to the network controller 40 to release the call with respect to the corresponding data call in which the error has occurred (step ST3). The stored data call information storage unit 56 is read out to determine whether the reservation end time has elapsed for this call (step ST4). That is, based on the data of the data call information storage unit 56, the reservation end time of the data call in which an error occurs is searched based on the counting time of the timer 54 provided therein.

Thus, if the end time has elapsed for the data call having an error, the network management system 50 outputs a call release command to the network controller 40 to perform a normal call release operation for the data call. If this has not elapsed, a call reset command is output to the network controller 40 to reassign other available communication channels and modems to provide the service to the subscriber (step ST5).

That is, according to the above embodiment, the network management system can minimize the communication failure by immediately releasing the communication modem and allocating another available communication modem when an subscriber has an error during communication, for example.

In addition, this invention is not limited to the said Example, It can variously deform and implement within the range which does not deviate from the technical summary of this invention.

As described above, according to the present invention, when an error occurs in a data call while a subscriber uses a reserved data call, the call is automatically released and a new available data call is reallocated to the subscriber. The present invention relates to a method of resetting a data call in a satellite communication system that minimizes communication disturbances.

Claims (2)

Claims [1] A satellite communication system comprising a network management system in which a plurality of subscribers and a plurality of base stations are coupled to each other, and a network control unit for managing the same through satellites and a manager to manage system congestion. When the base station communicates through a data call reserved by a subscriber, the base station continuously determines whether there is an error for the call, and when an error occurs, an error signal transmitting step of transmitting a predetermined error signal to the network controller; An error signal retransmission step of retransmitting the error signal to a network management system when the error signal is received; When the error signal is input from the network control unit, the network management system outputs a call release command for the data call in which the error occurs, and outputs a reassignment command for other available data calls. Data call reset method in a satellite communication system, characterized in that configured to include. The method of claim 1, If the call termination time has elapsed based on the call termination time for the data call after outputting a release command for the data call in which the error occurred in the data call reassignment step, the call termination time is not performed. And reselecting a data call reassignment step, reallocating another available data call if the elapsed time has not elapsed.