KR100221834B1 - Communication modem operation mode control method in satellite communication system - Google Patents

Abstract

The present invention relates to a method of controlling a communication modem operation mode in a satellite communication system that enables a communication network between a central control station and a base station to be secured by effectively managing an operation mode of a communication modem itself provided in a base station, A satellite communication system for providing communication between subscribers by combining a plurality of base stations combined with a satellite through a satellite; The base station searches for the operation state of the communication modem for the service data network. If the communication modem for the service data network is inoperable, the communication modem searches for the communication modem. If the communication modem is in the normal state and exists in the idle mode, A step of searching for a communication modem again if there is no communication modem which is in a normal state and in a hibernation mode and allocating it to a communication modem for a service data network if there is a communication modem which is a voice mode; Searching for a communication modem, and allocating the communication modem as a service data network communication modem if the communication modem exists as a data mode.

Description

Method for controlling communication modem operation mode in satellite communication system

The present invention relates to a communication system using a satellite, and more particularly, to a satellite communication system capable of securing a communication network between a central control station and a base station by effectively managing an operation mode of a communication modem, And a control method.

In recent years, with the rapid development of communication technology, satellite communication that enables subscribers located at a remote place to make calls through a satellite is gradually becoming common. Such satellite communication is useful for long distance communication between countries, or communication method of a mountainous country like Korea because a separate signal line is not required for communication.

In the above-mentioned satellite communication, a PAD (Pre Assignment Multiple Access) scheme in which each communication channel is reserved for each subscriber according to the channel allocation scheme, and a Demand Assignment Multiful Access (DAMA) scheme in which a communication channel is allocated according to a subscriber's request In general, in the satellite communication system for communication between subscribers, the DAMA system is adopted in consideration of the price and effectiveness of the communication channel.

FIG. 1 is a block diagram showing an overall system configuration of a general satellite communication system according to a DAMA scheme.

In FIG. 1, reference numeral 1 denotes a satellite having a plurality of communication channels, reference numeral 2 denotes a central control station for controlling the entire satellite communication system, reference numerals 3A and 3B denote exchangers 11A and 11B, telephones 12A and 12B, And the data terminals 13A and 13B and the facsimile machines 14A and 14B such as a computer and also has a function of communicating with the central control station 2 through the data transmission / .

In FIG. 1, reference symbol S denotes a service channel for transmitting and receiving control data, and T denotes a traffic channel for transmitting and receiving data and voice. The service channel S includes a TDM (Time Division Multiple) channel for transmitting control data from the central control station 2 to the base station 3 and a TDM (Time Division Multiple) channel for transmitting control data from the base station 3 to the central control station 2 S-ALOHA (Slotted ALOHA) channel.

In the above configuration, the central control station 2 transmits a control message through the service channel in a normal state, and then transmits a control message to each base station 3 based on a response message transmitted from the corresponding base station 3, And performs a polling function for checking the current state of the modem and the use state of the communication channel. When there is a call request from a specific base station, for example, the base station 3A to the terminal of the base station 3B, it is determined whether or not the base station 3B can communicate with the base station 3B based on the information obtained in the polling process And in the case where communication is possible, the available traffic channels T are allocated to the base stations 3A and 3B so that the base stations 3A and 3B can directly communicate with each other.

Then, when the communication end signal is applied via the service channel S from the base station 3A in which the communication between the base stations 3A and 3B has been completed and the communication request has been made, the central control station 2 transmits The communication end process is executed to release the traffic channel T that was provided to both the base stations 3A and 3B.

The control message such as the polling signal and the response message as described above is transmitted and received through a service data network which is a control communication network between the central control station 2 and the base station 3. The base station 3 transmits the service data One communication modem 24 is allocated in advance for the network.

That is, the base station 3 receives the TDM message transmitted from the central control station 2 for transmitting / receiving control data to / from any communication modem 24 to the central control station 2, ) As a communication modem for transmitting the S-ALOHA message.

However, when the communication modem 24 for the service data network becomes inoperable, the corresponding base station 3 can not communicate with the central control station 2 at all and can not provide the communication service to the subscriber.

Therefore, the base station 3 immediately searches for and allocates another available communication modem 24 when the currently assigned communication modem 24 becomes inoperable for the service data network, thereby communicating control data with the central control station 2 .

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a satellite communication system capable of ensuring a control communication network between a central control station and a base station by effectively managing an operation mode of a communication modem itself provided in a base station And a method of controlling a communication modem operation mode.

1 is a general system configuration diagram for explaining an outline of a general satellite communication system;

2 is a block diagram of a base station 3 for explaining a communication modem operation mode control system in a satellite communication system according to an embodiment of the present invention.

3 is a flowchart illustrating a method of controlling a communication modem operation mode in a satellite communication system according to an embodiment of the present invention.

* A brief description of the main parts of the drawing

1: satellite 2: central control station

3A and 3B: base stations 11A and 11B:

12A and 12B: telephones 13A and 13B: data terminals

14A, 14B: facsimile 21: antenna

22 RF processor 23 IF combination /

24: SCPC channel unit 20, 30: base station control unit

31: status information storage unit 32: mode information storage unit

A method for controlling a communication modem operation mode in a satellite communication system according to the present invention for realizing the above object is a satellite communication system for providing communication between subscribers by combining a plurality of base stations combined with a plurality of subscribers through an artificial satellite, The base station searches for the operation state of the communication modem for the service data network. If the communication modem for the service data network is inoperable, the communication modem searches for the communication modem. If the communication modem is in the normal state and exists in the idle mode, A step of searching for a communication modem again if there is no communication modem which is in a normal state and in a hibernation mode and allocating it to a communication modem for a service data network if there is a communication modem which is a voice mode; Searching for a communication modem, and allocating the communication modem as a service data network communication modem if the communication modem exists as a data mode.

That is, according to the above description, the base station effectively controls the operation mode of the communication modem and secures the communication modem for the service data network, so that the control data can be smoothly transmitted and received with the central control station.

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

2 is a block diagram illustrating a communication modem operation mode control system in a satellite communication system to which an embodiment of the present invention is applied.

Reference numeral 21 denotes an antenna for transmitting / receiving an uplink signal and a downlink signal to / from the satellite 1 and reference numeral 22 denotes an antenna for transmitting and receiving through the antenna 21, A low noise amplifier (LNA) for low noise amplifying a downlink frequency signal of, for example, 12.25 to 12.75 GHz input through the orthogonal mode transducer, an orthogonal mode transducer (OMT) A frequency down converter (DC: Down Converter) for converting a frequency signal applied through the low noise amplifier to an intermediate frequency signal IF of, for example, 70 MHz, an IF combination / Up converter (UC: Up Converter) for converting an IF signal of 70 MHz into a microwave of 14.0 to 14.5 GHz to generate an uplink frequency signal, and an uplink An RF processor configured to include: (High Power Amplifier HPA) high-power amplifier for amplifying the frequency signals.

Reference numeral 23 denotes an intermediate frequency signal applied from a communication modem (SCU) 24, which will be described later, by separating the intermediate frequency signal applied from the RF processor 22 into a plurality of intermediate frequency signals, 24 is a demodulator / demultiplexer for demodulating, decoding, and outputting an intermediate frequency signal applied from the IF combining / distributing unit 23, and outputs the demodulated and decoded intermediate frequency signal to the base station controller 20, (SCPC channel unit) which encodes and modulates a message output from the communication modem

Here, the IF combining / distributing unit 23 is employed for system scalability when a plurality of communication modems 24 _{1 to} 24 _n are used.

And, reference number 30 is a base station controller for controlling the overall apparatus of the base station 3, which is in particular a number of the communication modem (24 ₁ ~24 _n) continues to perform a polling operation to each of the communication modem (24 ₁ for the ~ 24 _n ) in accordance with the current state or the operation mode state. When a call is made from the subscriber, the base station control unit 30 generates a predetermined S-ALOHA message and transmits it to the central control station 2 through a communication modem for service data network (for example, , 24, ₁₎ through the transmission and to a central station 2, when the central control station 2, the traffic channel and the communication modem (24 ₁ ~24 _n) is assigned from received over the communications modem (24 ₁₎ And sets the communication modems 24 _{1 to} 24 _n to a predetermined operation state based on the following information to control communication between subscribers.

In addition, if reference numeral 31 is a current state of the communication modem (24 ₁ ~24 _n) in response to a control signal of the base station controller 30, that is, any communication modem (24 ₁ ~24 _n) is enabled "normal" state Or an unusable "unusable" state that can not be used, and 32 denotes a status information storage unit for storing the current operation mode of each of the communication modems 24 _{1 to} 24 _n according to the control signal of the base station control unit 30 Mode information for storing an operation mode such as a data mode for data communication, a voice mode for voice communication, a pause mode not yet assigned to data or voice mode, Wealth.

Next, a method of controlling a communication modem operation mode in a satellite communication system according to an embodiment of the present invention will be described with reference to the flowchart of Fig.

First, when the base station 3 starts up, the base station control unit 30 initializes the state information storage unit 31 and the mode information storage unit 32. Next, a polling operation is performed as to whether or not each of the communication modems 24 _{1 to} 24 _n is in a state where normal use is possible. Based on the response message input from each of the communication modems 24 _{1 to} 24 _n , And stores the operation states of the communication modems 24 _{1 to} 24 _n in the storage unit 31. This polling operation is continuously performed.

The base station control unit 30 allocates an arbitrary communication modem (for example, 24 ₁ ) available for the service data network with the central control station 2 based on the state data of the state information storage unit 31 addition is sent to the central station (2) the state information of the communication modem (24 ₁ ~24 _n) through the communication modem (24 _1).

Then, when the subscriber requests a call, the base station control unit 30 generates a predetermined S-ALOHA message and transmits it to the central control station 2 by using the communication modem 24 _{1 for the} service data network, When the traffic channel and the communication modems 24 _{1 to} 24 _n are allocated from the station 2 through the communication modem 24 ₁ , the mode information is stored in the mode information storage unit 32, The communication between subscribers is controlled by setting the modems 24 _{1 to} 24 _n to a predetermined operation mode (for example, data mode or voice mode).

Next, the base station controller 30 is a service data mangyong communication modem (24 ₁₎ bar which detect the operation state to continue, if the communication modem (24 ₁₎ is not operating normally (step ST1), the mode information storing And reads the mode information data from the modem 32 to search the status information and mode information of the communication modems 24 _{1 to} 24 _n except for the communication modem 24 ₁ used for the existing service data network (ST 2) .

When a communication modem (for example, 24 ₂ ) in a normal state and in a idle mode exists based on the state information and mode information of the state information storage unit 31 and the mode information storage unit 32 (ST 3) , The communication modem 24 ₂ is allocated for the service data network and transmission / reception of the control data with the central control station 2 is performed (ST 4).

On the other hand, if the communication modems 24 _{2 to} 24 _n which are in the idle mode are not present in ST ₃ , then it is searched whether the communication modems 24 _{2 to} 24 _n operating in the voice mode exist next (ST 5 step).

Communication that is operating in a voice mode at the ST5 step modem (for example, 24 ₃₎ If it does exist, the communication modem (24, ₃₎ the use and perform forced releases the call with respect to the call in the following this service data mangyong communication modem (24 ₃₎ assigned to it is controlled to perform the transmission and reception of control data between the central control station (2) (step ST6).

On the other hand, if the communication modems 24 _{2 to} 24 _n which are voice modes are not present in step ST 5, then it is searched whether there are communication modems 24 _{2 to} 24 _n operating in the data mode next (ST 7 step).

Communication that is operating in a data mode in the ST7 step modem (for example, 24 ₄₎ if the number there is a communication modem (24, ₄₎ the use and perform forced releases the call with respect to the call in the following this service data mangyong communication modem (24 ₄₎ is assigned to control to carry out transmission and reception of control data between the central control station (2) to (step ST8).

On the other hand, if there is no communication modem 24 _{2 to} 24 _n in the data mode in step ST 7, the process proceeds to step ST ₂ to repeat the operation procedure

That is, according to the above description, the base station effectively manages the operation mode of the communication modem, thereby securing the communication network between the central control station and the base station.

The present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the technical spirit of the present invention.

As described above, according to the present invention, a communication modem operation mode control method in a satellite communication system that enables a communication network between a central control station and a base station to be secured by effectively managing an operating mode of a communication modem, .

Claims (2)

A satellite communication system for providing communication between subscribers by combining a plurality of base stations, each associated with a plurality of subscribers, via a satellite, the system comprising: The base station retrieving an operating state of the communication modem for the service data network, Searching the communication modem if the communication modem for the service data network is inoperable and allocating the communication modem for the service data network to the communication modem for the service data network if the communication modem is in the normal state and in the idle mode, Searching for a communication modem again if there is no communication modem in a normal state and a dormant mode and assigning it to a communication modem for a service data network if the communication modem is in voice mode, Searching for a communication modem again if there is no communication modem as a voice mode, and allocating the communication modem as a communication data modem for a service data network if the communication modem exists as a data mode. Way. The method according to claim 1, Further comprising the step of continuously searching for a current state of the communication modem if the communication modem does not exist in the data mode.