JPH0379895B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is directed to network control in a satellite communication system that is composed of a large number of small earth stations and that allocates satellite lines appropriately each time a call is generated from each of these small earth stations. , especially regarding the system configuration related to the cancellation of satellite link settings.

(Prior Art) A typical satellite communication system currently in operation is the American SBS (Satellite Business System). This system is primarily intended for domestic communications within the United States, and its configuration is shown in Figure 1.
In this system, as shown in Figure 1, in addition to a large number of small earth stations and multiple terminal users connected to each of them, there is also an earth station called a network control center (NCC) within the system. One station is arranged. The NCC is a station that controls the entire network, and its main functions include understanding the transmission characteristics of satellite lines and system operation status, and allocating satellite lines in response to call requests from each small earth station. In other words, to cancel the satellite line settings, first the NCC receives a call request from the user terminal transmitted via the small earth station,
After verifying the user, the satellite line is assigned to the small earth station. In addition, the NCC detects the start and end of communication between user terminals, and executes billing processing for users and filing of call processing information, etc. SBS provides domestic communications via satellite, and even if one NCC station manages information about users all at once, there will be no problem since it is a domestic matter.

(Problem to be solved by the invention) However, when this type of system is applied to international communications spanning multiple countries or domestic and international communications consisting of multiple communication carriers, user-related information is 1 like
Centralized management at a central office is not necessarily preferable, considering the complexity of processing and the individual circumstances of each country (each communication carrier). The present invention addresses the above-mentioned problems that occur when a satellite communication system consisting of a large number of small earth stations such as the US SBS is extended to international communication spanning multiple countries or domestic and international communication operated by multiple communication carriers. This paper describes a system configuration that solves the problem.

(Structure and operation of the invention) Before explaining the present invention in detail, for reference, user information management in two types of international communications currently in use will be described. FIG. 2 shows the basic configuration of a public international communication system, which is composed of user terminals, subscriber lines, domestic exchanges, domestic transmission lines, international exchanges, and international transmission lines. When a user wishes to carry out international communication, the domestic switching center uses the destination user terminal number sent from the user terminal to
The call request is forwarded to the international exchange. After verifying the user, the international exchange establishes an international transmission path with the international exchange to which the destination user belongs, and calls the destination user terminal. In this configuration, user verification, billing processing, filing of call processing information, etc. are performed at the international switching center. Since international exchange offices are located in each country, information management and response processing for users will be carried out in each country, and there is no need for each international exchange office to own information about users outside of its own country, and circumstances will vary depending on each country. This allows various types of processing to be executed. That is,
In current public international communication via international exchange offices,
It can be seen that no particular problem arises because the management of user information is carried out in a distributed manner in each country or each communication carrier.

Next, network control in an international maritime satellite communication system similar to the situation assumed by the present invention will be described. Figure 3 shows the configuration of the international maritime satellite communication system, where the satellite side includes a ship earth station,
Coast Earth Station (CES), Network Coordination Station:
NCS), and the land side is similar to public international communications,
It consists of international transmission lines, international exchanges, domestic transmission lines, domestic exchanges, subscriber lines, and user terminals.
NCS is installed as one station within the system and manages the system mainly by allocating satellite lines. CES
There are multiple stations in the system, and satellite links are set up with the ship's earth station for telephone and telex communications. In response to a call originating from a land-based user, the international switching center identifies the destination ship's earth station by sea area information and transfers the call to the corresponding CES. On the other hand, when a call is made from a ship's earth station, the CES identifies the number of the other land user and transfers the call to the international switching center corresponding to the other land user. Communication between ship earth stations is relayed by CES,
This is achieved by passing through the satellite line twice. FIG. 4 shows the concept of the satellite line setup procedure, and all calls will be setup via CES. As shown in the figure, NCS is CES
In response to the line requests issued from the CES, the line is allocated to the ship's earth station and the CES. In addition,
Since CES is not located in each country, communication with domestic land users that do not have CES is
An international transmission path is set up between the international exchange center of the country that has the CES and the international exchange center of the country where the land user is located.

User verification and billing for each user regarding user information management in the international maritime satellite communication system have become quite complex, and are as follows.

(1) Verification of land users will be performed at the international exchange office of the country to which the user belongs.

(2) Verification of ship earth station users will be performed at CES.

(3) Billing for calls made by ship earth station users and received by land users shall be done at CES.

(4) Telex charges for land user communications originating from ship earth station users shall be made at the international exchange office in the country where the CES is located.

(5) Charges for calls made by land users shall be made at the international exchange office of the country to which the land user belongs.

(6) Billing for communication between ship earth station users shall be done at CES.

To summarize the above, basically, processing for land users is performed at the international exchange office, and processing for ship earth station users is performed at the CES.

The system envisaged by the present invention is an extension of the US SBS, and unlike the above-mentioned public international communications and international maritime satellite communications, communication lines are not set up via an international switching center or CES. Furthermore, it is not possible to classify users into two types, such as ship earth station users and land users, as in international maritime satellite communications, but rather to classify users into groups of multiple users belonging to each country or communication carrier. It is. In other words, in this system, a direct satellite link is set up between small earth station users, and communication is performed by users classified into multiple types, so management of user information requires consideration of special circumstances as described above. It is necessary to give sufficient consideration. Figure 5 shows the system configuration of the present invention, in which only one station (hereinafter referred to as system management station) that executes system management centered on satellite line allocation is placed in the system, and Alternatively, a bureau (hereinafter referred to as an information management bureau) is established for each communication carrier to manage information on users affiliated with the organization. FIG. 6 shows the flow of network control in this system. As shown in the figure, the small earth station user makes various requests and responses to the system management station, and the information management station monitors the exchange of information between the system management station and the small earth station user, and collects user information. Provide necessary items to the System Management Bureau as appropriate. Figure 7 shows an example of the line setting procedure in this system configuration. Since the information management station does not directly intervene in the information transmission between the system management station and small earth station users, the line setting can be shortened. Can be done in time. On the other hand, in the case of international maritime satellite communications, as shown in Figure 4, call requests from ship earth station users are always sent via CES.
Since the information is transmitted to NCS, the time required to set up the line will be slightly longer. As described above, in the system configuration according to the present invention, the system management station only performs system management centered on satellite line allocation, and does not need to manage user information. On the other hand, the Information Management Bureau will manage user information related to its own country or its own business entity, and will be able to independently manage and operate information such as user verification and user billing, and This makes it possible to prevent various problems from occurring over time.

(Effects of the Invention) As described above in detail, the present invention is directed to a satellite communication system that is composed of a large number of small earth stations, and in which a satellite line is appropriately allocated each time a call is generated from each of the small earth stations. In the system configuration, satellite links are not only allocated to each small earth station user under centralized control, but also user-related information is allocated to each user's country or communication carrier, similar to current public international communications. It becomes possible to manage and operate the By adopting this configuration, it is possible to obtain the advantage that user information can be managed independently in each country or each communication carrier.

[Brief explanation of drawings]

Figure 1 shows the system configuration of the US SBS, Figure 2 shows the basic configuration of the public international communications system, Figure 3 shows the configuration of the international maritime satellite communications system, and Figure 4 shows the procedure for setting up telephone lines (ship to land) in the international maritime satellite communications system. Conceptual diagram,
Figure 5 shows the system configuration according to the present invention, Figure 6 shows the flow of network control in the system configuration according to the present invention, and Figure 7
1 is an example of a satellite line setting procedure in a system configuration according to the present invention.

Claims (1)

[Claims] 1. In a satellite communication system that is composed of earth stations that support a plurality of users, a satellite line is appropriately allocated each time a call is generated from each of these earth stations, and a direct satellite communication line is established between the earth stations. In addition to compatible earth stations, it consists of one earth station that performs system management centered on satellite line allocation, and multiple earth stations that manage information on users affiliated with each country or communication carrier. The earth station that manages the information of the affiliated users mentioned above monitors the transmission of information between the only earth station that manages the system and the user earth station, and manages the system as appropriate with information regarding the user earth station. A satellite communication method characterized by providing to the above earth station.