JPH0355926A - Satellite communication demand assign multiple access system - Google Patents

Abstract

PURPOSE:To improve the utility of a line and to improve the call processing capability by allowing a controller of a control earth station to accept a recall reservation when a call connection requested by a communication earth station is not established, and applying automatic call connection by the controller when the cause of unestablishment is eliminated. CONSTITUTION:When a line 101 is connected between communication earth stations 3, 4 and they are busy, a call is not established, then a terminal equipment 51 of a communication earth station 5 sends a recall reservation signal 102 to a DAMA controller 21 of a control earth station 2. The DAMA controller 21 receives a recall reservation and decides the order of reception or priority order for calls including other received recall reservation signal. When the communication earth station 3 is idle, a start signal 103 is sent to a reserved station 5 and an incoming station 3 in the order based on a prescribed rule and a series of control applying call connection is executed. A terminal equipment 51 of the communication earth station 5 and a terminal equipment 31 of the communication earth station 3 start signal transmission by the reception of the start signal 103 from the DAMA controller 21.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a satellite communication demand assignment multiple access system, and more particularly to a satellite communication demand assignment multiple access system in a circuit-switched satellite communication network.

[Conventional technology]

Traditionally, there are two types of networks, whether terrestrial communication networks or satellite communication networks: real-time circuit switching networks and waiting packet switching networks. Facsimile etc. mainly use circuit-switched networks, data transmission mainly uses packet-switched networks,
Each has been used in a way that takes advantage of its characteristics.

In the case of circuit-switched networks, calls with large amounts of information and long hold times,
It is suitable for facsimile and image information transmission, but when the line is busy or the other party's station is in use, the call is dropped and a repeat call is required. For this reason, facsimiles, etc., generally have a function that automatically calls back after a random period of time. [Problem to be solved by the invention] Conventional satellite communication demand assignment multiple access operating as a circuit switched network
t MuItiple Access; DAMA)
In this method, when the requested call connection is not established, the terminal
Another drawback is that calls are made after a random period of time, which results in wasted line usage.
An object of the present invention is to provide a satellite communication demand assignment multiple access system that can improve line usage efficiency by automatically establishing a call connection when the cause of the call connection failure is eliminated. [Means for solving the problem] The satellite communication demand assignment/multiple access system of the present invention is as follows:
A plurality of communication earth stations, each equipped with a terminal that sends a recall reservation signal when a requested call connection is not established and starts signal transmission when a recall activation signal is received, and allocation of communication lines shared by these communication earth stations. a control earth station, the control earth station comprising a control device that receives the recall reservation signal and transmits the recall activation signal in an order based on a predetermined rule when the cause of the failure is eliminated. It is equipped with the following. [Example] Next, the present invention will be described with reference to the drawings.

Both FIG. 1 and FIG. 2 are diagrams for explaining the operation of an embodiment of the present invention. This embodiment includes a communication satellite 1, a large number of communication earth stations that communicate with each other via the communication satellite 1, and a control earth station that includes a DAMA control device 21 that controls the allocation of lines used by these communication earth stations. It is guarded with the following. For convenience of explanation, three communication earth stations 3 are shown in Figure 1 as communication earth stations.
-5, and only seven communication earth stations 3-9 are shown in FIG. Communication earth stations 3-9 are equipped with terminals 31-91. Referring to FIG. 1, when there is a call connection request from the communication earth station 5 to the communication earth station 3, the line 101 is connected between the communication earth station 3 and the communication earth station 4 and is in use. However, at this time, the terminal 51 of the communication earth station 5 sends a recall reservation signal 10 to the DAMA control unit W21 of the control earth station 2.
Send 2. The DAMA control device 21 accepts the re-booking,
When the communication earth station 3 becomes vacant, the reserved station (communication earth station 5 in Figure 1)
) and its destination station (communication earth station 3), and executes a series of controls to connect the call. The terminal 51 of the communication earth station 5 and the terminal 31 of the communication earth station 3 start signal transmission upon receiving the activation signal 103 from the DAMA control device 21.

Next, assuming that the number of lines allocated to communication earth stations 3 to 9 in this embodiment is two lines, and referring to FIG. When the line 104 and the line 105 between the communication earth station 5 and the communication earth station 9 are already in use, even if there is a call connection request from the communication earth station 6 to the communication earth station 8, the line 105 is free. Therefore, the call ends up being unsuccessful even though the communication earth station 8 is not in use. At this time, from communication earth station 6 to D
A recall reservation signal 106 is transmitted to the AMA control device 21.
The DAMA control device 21 selects a reservation station (see FIG. Then, a start signal 107 is sent to the communications earth station 6) and its destination station (communications earth station 8), and a series of controls for making a call connection are executed. The terminals 61 and 81 of the communication earth stations 6 and 8 start signal transmission upon receiving the activation signal 107 from the DAMA control device 21.

〔Effect of the invention〕

As explained above, in the present invention, when a call connection requested by a communication earth station is not established, the control device of the controlling earth station accepts a re-call reservation, and when the cause of the failure is eliminated, the control device automatically By making a call connection, it is possible to improve the convenience of the user who communicates from the terminal of the communication earth station, and also to increase the utilization rate of the line, which is a limited resource, and to increase the call processing capacity.

[Brief explanation of drawings]

Both FIG. 1 and FIG. 2 are diagrams for explaining the operation of an embodiment of the present invention. 1...Communication satellite, 2...Control earth station, 3-9...
Communication earth station, 21...DAMA control device, 31-91
...Terminal.

Claims (1)

[Claims] A plurality of communication earth stations, each equipped with a terminal that sends a recall reservation signal when a requested call connection is not established and starts signal transmission when a recall activation signal is received, and allocation of communication lines shared by these communication earth stations. a control earth station comprising a control device that controls the recall reservation signal according to a request of the communication earth station, receives the recall reservation signal, and transmits the recall activation signal in an order based on a predetermined rule when the cause of the failure is eliminated. A satellite communication demand assignment multiple access system characterized by comprising: