JPH03187531A - Supervisory and controlling system for satellite communication - Google Patents

Abstract

PURPOSE:To improve entire polling efficiency by polling another station whose line is not interrupted, during standby time until a public line is connected. CONSTITUTION:Since interruption information Ub-Ue are inputted to a supervisory and control data processing part 20' as well, the supervisory and control data processing part 20' can know whether the line of the startion starting a polling operation is interrupted or not, namely, whether the public line is used or not. When the two stations can be polled at least during the standby time until the public line is connected, the supervisory and control data processing part 20' sends out a polling signal through the public line and afterwards, until a response is returned, the two stations succeeding scheduling polling are polled. Then, a response from the public line is waited. Thus, even when the line is interrupted and replaced with the public line, the polling processing can be efficiently executed.

Description

[Detailed Description of the Invention] [Required] Concerning a satellite communication monitoring and control system that centrally monitors and controls a large number of unmanned stations using a satellite line backed up by a public line, the problem arises when the public line is used due to a satellite line disconnection. The purpose of this research is to propose a method for efficiently performing polling processing even when there is In a satellite communication monitoring and control method that monitors and controls an unmanned station via a public line, after sending a polling signal via the public line and before receiving a response signal, a polling signal is sent to at least one other station whose line is not disconnected. Configure to perform polling.

[Industrial application field]

The present invention relates to a satellite communication monitoring and control system that centrally monitors and controls a large number of unmanned stations that perform satellite communication.

When centrally monitoring and controlling a large number of unmanned stations that communicate via communication satellites, it is necessary to reliably grasp the status of the unmanned stations even if there is an abnormality in the transmission path such as rain.
The monitoring and control line is backed up by a public terrestrial line, separate from the satellite communication line.

The present invention refers to this type of satellite communication monitoring and control system.

[Conventional technology]

FIG. 3 is a diagram conceptually representing a system for centrally monitoring and controlling a large number of ground stations that communicate with each other via communication satellites.

The ground stations 108 to 10e are connected by a satellite line using the communication satellite 12 as a relay station. Among them, ground stations 10b to 10
e is an unmanned station, and 10a connects them to the satellite monitoring and control line S.
, ~S, are centrally monitored and controlled.

Normally, the ground station 10a sequentially sends polling signals to the supervisory control lines S, -S, in order to monitor the status of each unmanned station 10b-10e, and in response, the ground station 10b-10e monitors the status of each unmanned station, e.g. It sends out various warnings such as the presence or absence of rain, the reception level, the opening/closing status of station building doors, and equipment failure.

This supervisory control line 5b-s is connected to the supervisory control line using a public line on the ground so that even if the satellite line is interrupted due to an abnormality in the transmission line such as rain, the unmanned station can continue to be monitored and controlled. A 0 is provided as a backup for the line.

When it is detected that one satellite monitoring control line on the ground station 10a side is disconnected, it is immediately switched to the public line monitoring control line Kb-, and monitoring continues.

FIG. 4 is a block diagram showing the configuration of an SV (supervisory) provided for remote monitoring and control in the ground station 10a that performs remote monitoring and control.

The supervisory control data processing unit 20 includes a CPU, and creates commands for control, creates polling commands, or decodes responses from each ground station in response to commands from connected input/output devices or a personal computer. The data is then sent to an input/output device or a burner computer. The monitoring control data raw bottom section 20 performs parallel←→serial mutual changes. The route branching unit 24 switches the sending or receiving destination under control from the supervisory control data processing unit 20. The line disconnection detection lines 26b to 26e pass received and transmitted signals, and when the received signal is abnormal for a predetermined period or longer, disconnection information U is detected as a line disconnection.
, ~U6 are output. When the line is disconnected, the public line connection unit 28 connects to the public line monitoring control line to ~ (Figure 3)
It is for communicating using. Public line connection part 2
8 has a table of telephone numbers, and line disconnection information U,
When a command such as polling is sent to a ground station where ~U is enabled, a signal of the corresponding telephone number is sent to the public line via the modem 30 to connect a backup line.

The supervisory control data control unit 20 repeats polling processing to monitor the status of each station while no control command is input from the input/output device or the personal computer.

FIG. 5 is a timing chart when the ground stations 10a to 10b to 10e are polled in sequence. Ground station tO
t for the polling signal B from a to the ground station 10b.
After a delay of 1 second, a response B and ANS are returned from the ground station 10b, and after receiving the response, a polling signal C is sent to the ground station 10C, and so on. ~10. polling is repeated.

[Problem to be solved by the invention]

For example, if there is some abnormality in the ground station 10C (Fig. 3) and the line is disconnected, and the disconnection information U, (Fig. 4) is output, the public line connection unit 28 (Fig. 4) performs public line monitoring control. The line KC (Fig. 3) will be replaced by the satellite monitoring control line Sc. In this case, the polling signal C (
The response to Fig. 5 will return to t2 seconds (Fig. 5), but since it includes procedures such as exiting the dial signal, tl
It will take tens to hundreds of times more. As a result, the overall polling cycle becomes longer. The problem is that it becomes inefficient.

Therefore, an object of the present invention is to propose a satellite communication monitoring and control system that efficiently performs polling processing even when the line is disconnected and replaced with a public line.

[Means to solve the problem]

The satellite communication monitoring and control system of the present invention uses one line of multiple satellite communication lines to poll unmanned stations sequentially to perform monitoring and control of the unmanned stations, and also uses a public line for unmanned stations whose line is disconnected. A satellite communication supervisory control method that performs supervisory control via a public telephone line, which is characterized by polling at least one station whose line is not disconnected after sending a polling signal via a public line and before receiving a response signal. be.

[For production]

By polling other stations whose line is not disconnected during the waiting time until the public line is connected, the overall polling efficiency is improved.

The minimum time required to connect to the public line can be calculated from the length of the telephone number, etc., and the time required for polling via the satellite line can also be known in advance.
It is possible to know in advance whether polling of other stations can be carried out at least through the satellite line during the waiting time.

〔Example〕

FIG. 1 is a diagram showing the configuration of an SV for implementing the method of the present invention. Components that are the same as those in FIG. 4 are given the same reference numerals, and their explanations will be omitted.

Unlike FIG. 4, disconnection information U, -U is also input to the supervisory control data processing section 20'. Therefore, the supervisory control data processing unit 20' can know whether the line of the station that has entered the polling operation is disconnected, that is, whether or not the public line is being used.

Assuming that polling of at least two stations is possible during the public line connection waiting time, the supervisory control data processing unit 20'
After sending out a polling signal via the public line, it polls the two stations scheduled to be polled next before receiving a response, and then waits for a response from the public line.

FIG. 2 is a timing chart showing an example of polling according to the method of the present invention.

This figure shows an example in which the satellite link to the ground station 10C (FIG. 3) is disconnected. Immediately after the polling (BSB, ANS) for the ground station 10b is completed and the polling signal (C) is sent to the ground station IOC via the public line, polling processing (D
, D, ANS, E, B, ANS), and then receives a response (C0ANS) from the ground station 10C and polls the ground station 10b.

〔Effect of the invention〕

As described above, according to the present invention, even when the satellite line is disconnected due to factors such as deterioration of the transmission line and polling has to be performed via the public line, polling can be performed efficiently. A supervisory control scheme is provided.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an embodiment of the present invention, Fig. 2 is a timing chart showing the polling order according to the method of the present invention, Fig. 3 is a conceptual diagram of a remote monitoring and control system using a satellite line and a public line, and Fig. 4 The figure shows the configuration of a conventional SV, and FIG. 5 is a timing chart showing the polling order according to the conventional method. In the figure, 20.20'... supervisory control data processing section, 22...
Supervisory control data generation section, 24... Route branching section, 26b to 26e... Line disconnection detection section, 28... Public line connection section, 30... Modem.

Claims (1)

[Claims] 1. Monitoring and controlling the unmanned stations by sequentially polling the unmanned stations using one of the multiple satellite communication lines,
In a satellite communication supervisory control method that monitors and controls an unmanned station whose line is disconnected via a public line, after sending a polling signal via the public line and before receiving a response signal, at least one other station whose line is not disconnected is A satellite communication monitoring and control method characterized by polling.