KR100243500B1 - Method and Apparatus for Assigning Channels in Satellite Communication System - Google Patents

Abstract

The present invention relates to a system and method for searching for a channel of a satellite communication system capable of efficiently managing a channel when a call request with the same bandwidth is requested by searching for a channel allocated to a corresponding bandwidth size based on previous channel allocation information, And a method of allocating the same.

The channel allocation according to the present invention is a method of reading the status information of a called base station obtained by polling when a call request is made from an arbitrary subscriber to check whether the paged subscriber is in a call available state, If it is determined that the channel is available, the channel previously assigned as a call of the same bandwidth is preferentially searched and it is determined whether or not the channel is currently assignable as a call having the same bandwidth so that the channel can be identified as an assignable channel The channel is allocated as a communication channel.

Description

TECHNICAL FIELD [0001] The present invention relates to a channel allocation method and apparatus for a satellite communication system,

In particular, the present invention relates to a communication system using a satellite, and more particularly to a communication system using a satellite, in which a channel that has been allocated to a bandwidth size based on previous channel allocation information is first searched for a call request of a subscriber, And more particularly, to a channel allocation method and apparatus for a satellite communication system that can be managed.

The channel allocation operation in the satellite communication system mainly used for remote ground communication is performed by the central station that manages the overall network operation state. FIG. 1 illustrates a channel allocation process in the DAMA-SCPC system satellite communication system Fig. 2 is a schematic block diagram of a central station.

1, reference numeral 10 denotes an antenna for transmitting and receiving an UP LINK signal transmitted to a satellite (not shown) and a DOWN LINK signal transmitted from a satellite, And converts an intermediate frequency (IF) signal of a 70 MHz band into an RF signal of a very high frequency band in response to the uplink signal, and at the same time, converts the downlink signal of the ultra high frequency band into an intermediate frequency The RF transceiver 20 includes an Orthogonal Mode Transducer (OMT) 21 for separating and inputting and outputting uplink and downlink signals transmitted and received through the antenna 10 using the polarization characteristics of frequency ) And a 12.25-12.75 GHz downlink frequency signal separated and input by the orthogonal mode converter 21 to a predetermined level and amplifies the amplified signal to an intermediate frequency (IF) of 70 MHz, for example, An RF transmitter 22 for converting an intermediate frequency (IF) signal of 70 MHz to be transmitted to the satellite into an ultra-high frequency of 14.0 to 14.5 GHz and amplifying the signal to a predetermined level to generate an uplink frequency signal; (23).

Reference numeral 30 denotes an IF processing stage for processing a transmission and reception intermediate frequency (IF) signal in the 70 MHz band. The IF processing stage 30 receives an intermediate frequency (IF) signal from the RF receiving section 22 An intermediate frequency combining / distributing unit IF for separating and outputting a plurality of intermediate frequency signals and combining and outputting intermediate frequency signals applied from a single channel per channel (SCPC) unit 33, which will be described later, A first SCPC channel unit for demodulating and decoding the IF signal applied from the intermediate frequency combining / distributing unit 31 and a message output from the network controller 40 to be described later, And a second SCPC channel unit 33 for outputting the encoded and modulated signals.

Reference numeral 40 denotes a polling function for sending a control message to each base station through the SCPC channel unit 33 and for checking the status of each base station based on a response message transmitted from the corresponding base station, If there is a call request from the base station, it is determined whether the counterpart base station is capable of communicating based on the information obtained in the polling process. If the communication is enabled, a traffic channel available to the satellite is allocated to both base stations, To perform mutual communication directly, and the like.

The network control unit 40 controls the entire system and extracts packet information from a message received from the processor 41 and the SCPC channel unit 32, A service channel controller (SCC) 42 for generating and outputting a message of a TDM (Time Division Multiplex) stream to the SCPC channel unit 33, A dual port RAM 43 for transmitting and receiving data between the channel controllers 42, a program storage unit 44 for storing an operation program of the processor 41, and status information of each base station obtained by the above- A base station information storage unit 45 for storing the base station information, and a channel information storage unit 46 for storing the use state of the communication channel.

Reference numeral 50 denotes a network management system that allows the satellite communication network management manager to monitor the overall operation status of the network and control the entire satellite system including the base station as needed.

That is, in the conventional satellite system configured as described above, when there is a call setup request from an arbitrary calling subscriber base station (not shown), the processor 41 in the network control unit 40 transmits the base station information And a channel of the requested bandwidth among the currently available communication channels based on the channel status information recorded in the channel information storage unit 46. [

Meanwhile, the calling base station (not shown) requires a bandwidth of an appropriate size when a call is requested according to whether the content to be communicated is a voice call or a data call. In the case of bidirectional voice communication (TX) channel (30KHz band) and receiving (RX) 1 channel (30KHz band). However, in case of data communication, 1MHz (about 30 channels) About 60 channels).

Accordingly, when a call request requiring such various sizes of bandwidth is accommodated in a single satellite repeater, although the positions occupied by the respective communication calls are distributed to a plurality of locations, the channel of the required bandwidth remains as a whole However, there is a problem in that the usable communication channels are dispersed in various places, and the call setup request can not be accepted.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a mobile communication system and a mobile communication method, in which, when a call allocated to a predetermined bandwidth size is released after a call is terminated, The present invention provides a channel allocation method and apparatus for a satellite communication system that can efficiently manage a channel when a call request having the same bandwidth is searched for by first searching for a channel allocated to the bandwidth size.

1 is a diagram for explaining a channel allocation process of a general satellite communication system;

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a satellite communication system, and more particularly,

3 is a diagram illustrating memory mapping of the channel allocation information storage unit 146 shown in FIG.

FIG. 4 is a flowchart for explaining the operation of the apparatus having the configuration of FIG. 2;

DESCRIPTION OF THE REFERENCE SYMBOLS OF THE DRAWINGS OF THE DRAWINGS ********

10: antenna 20: RF transmitting / receiving terminal

21: Orthogonal Mode Transducer (OMT)

22: RF receiving unit 23: RF transmitting unit

30: IF processing stage 31: Intermediate frequency combination / division (IF C / D)

32, 33: SCPC channel unit 40: Network control unit

41, 141:

42: Service Channel Controller (SCC)

43: dual port RAM 44: program storage unit

45: base station information storage unit 46: channel information storage unit

50: network management system 146: channel allocation information storage unit

According to a first aspect of the present invention, there is provided a channel allocation method for a satellite communication system, including: a call request confirmation step of confirming whether a call request is made from an arbitrary subscriber; A caller's call availability confirmation step of reading the status information of the base station and confirming whether the called party is in a callable state or not, A pre-assigned channel preferential search step of preferentially searching for a channel previously assigned as a call of the same bandwidth and determining whether or not the corresponding channel is currently assignable as a call having the same bandwidth, If the channel is determined to be a channel that can be allocated, Characterized in that configured to include a channel allocation step of allocating a new channel.

According to a second aspect of the present invention, there is provided a channel allocation apparatus for a satellite communication system, comprising: a plurality of base stations coupled to a plurality of subscribers; a satellite for providing a communication channel between each base station; A satellite communication system having a central control station for assigning and controlling an available communication channel of the satellite communication system; The central control station comprises: base station information storage means for storing status information of each base station obtained by the polling operation; and a base station information storage means for storing status information of each channel provided by the satellite, A channel allocation information storing means for storing bandwidth size information as data and a channel allocation information storing means for controlling the overall system and allocating a channel allocated to a corresponding bandwidth based on data stored in the channel allocation information storing means as a call of the same bandwidth And a control means for assigning and controlling the corresponding channel as a communication channel when it is determined that the state is available.

That is, according to the present invention having the above configuration, when a call request having the same bandwidth is searched for a channel that has been allocated with the same bandwidth size based on the previous channel allocation information for a call request of the subscriber, the channel is efficiently managed .

Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings.

FIG. 2 is a block diagram schematically showing the configuration of a central station of a satellite communication system provided with a channel allocation function according to the present invention. Components having substantially the same functions as those shown in FIG. 1 are denoted by the same reference numerals , And a detailed description thereof will be omitted.

In FIG. 2, reference numeral 146 denotes channel allocation information for storing about 1200 channels provided by the satellite transponder, whether the current channel is available and size information of bandwidth allocated at the time of previous channel storage As shown in FIG. 3, the channel allocation information storage unit 146 stores a state data storage area in which state data of '0' or '1' is stored according to whether a channel is used or not, And a previous allocation information storage area in which 2-bit previous channel bandwidth information is stored according to the size of the bandwidth. Here, the previous 2-bit channel information is, for example, binary data '00' when the channel was allocated as a call having a bandwidth of 30 KHz at the time of previous channel, and channel For example, binary data '01', and binary data of '11' in the case of a channel assigned to a 2 MHz bandwidth, and '10' in the case of a channel assigned as a call having a 1 MHz bandwidth .

Meanwhile, reference numeral 141 denotes a system for controlling the entire system, and a channel allocated to a corresponding bandwidth for a call setup request from an arbitrary base station based on data stored in the channel allocation information storage unit 146, Is a processor that first searches for a recognition.

Next, the operation of the apparatus having the above-described configuration will be described with reference to the flowchart of FIG.

When a call request is made from an arbitrary subscriber (ST 1), the processor 141 reads the status information of the called base station obtained by the polling from the base station information storage unit 45 (ST 2), and the called subscriber It is confirmed whether or not the communication is available (ST 3).

If it is determined in step ST3 that the called party is currently in a call with another subscriber or the base station is in a state in which communication is impossible due to a system error or the like, (ST4). If it is confirmed that the communication is possible, the channel assignment information storage unit 146 searches for a channel previously assigned as a call having the same bandwidth (ST5) It is determined whether the channel is currently available as a call having the same bandwidth (ST 6).

If it is determined in ST 6 that the current channel can be allocated as the same bandwidth, the processor 141 transmits a predetermined message to both base stations and allocates the corresponding channel as a communication channel (ST 9) , The processor 141 sequentially searches the channel allocation information storage unit 146 (ST 7), and if it is determined that the channel having the corresponding bandwidth It is confirmed whether there is a channel available in the middle (ST 8).

On the other hand, if the available channel index result available channel in step ST8 is confirmed, the processor 141 proceeds to step ST9 to allocate the corresponding channel. If there is no available channel, the process proceeds to step ST4 And a call disable message is transmitted to the calling subscriber side.

When the channel allocation operation in step ST9 is completed, the processor 141 changes the corresponding data set in the status data storage area of the channel allocation information storage unit 146 to '1' Is being used (ST 10).

Then, the processor 141 checks whether a call termination message is received from the calling base station (ST 11). When it is confirmed that the call is terminated, the processor 141 sets the corresponding channel status data of the channel assignment information storage unit 146 to '0' (ST 12), and the channel band information set in the previous allocation information storage area of the corresponding channel is updated and stored (ST 13), thereby terminating a series of channel allocation operations to be performed by the above-described process.

As described above, according to the present invention, when a call allocated to a predetermined bandwidth size is released after a call is terminated, the set location information is stored, and if a call request of the same bandwidth occurs, It is possible to efficiently manage the channel when there is a call request having the same bandwidth by searching for the allocated channel first.

Claims (4)

A pre-allocated channel information storing step of storing channel information of each pre-allocated channel by frequency bandwidth, A caller call availability confirmation step of reading out status information of a called base station and confirming whether the called party is in a callable state when there is a call request from an arbitrary subscriber, When it is confirmed that the callee subscriber is currently in a talkable state, channel information having the same frequency bandwidth as the requested frequency bandwidth from the corresponding call subscriber among the channel information stored in the pre-allocated channel information storage step is searched for and the channel And allocating a channel to the channel allocation step. The method according to claim 1, If it is determined that the corresponding channel is not assignable in the same frequency bandwidth channel information allocated in the channel allocation step, the remaining channels are sequentially searched in the same frequency bandwidth channel information, and a usable channel among the channels having the same bandwidth A residual channel indexing step for indexing, Further comprising allocating an allocatable channel as a communication channel according to an available channel index result by the residual channel indexing step. A satellite communication system having a plurality of base stations each associated with a plurality of subscribers, and a central control station for controlling to allocate a communication channel usable in a satellite to a base station having a satellite and a call request for providing a communication channel between each base station ; The central control station includes base station information storage means for storing status information of each base station obtained by the polling operation, Channel allocation information storage means for storing channel information allocated at the time of previous channel allocation for each frequency bandwidth and for storing information on whether the channel information is available for the channel information, And if there is a call request, the channel allocation information storage means preferentially reads available channel information among channel information having the same frequency bandwidth as the frequency bandwidth required in a call request, and allocates the channel information to the communication channel And a control unit for controlling the channel of the satellite communication system. The method of claim 3, Wherein the control unit indexes an allocatable channel for the remaining channels based on the data stored in the channel allocation information storage unit when the channel is determined to be in an unallocatable state as a result of the priority search, And allocates the assignable channel as a communication channel.