JPS61290825A - Satellite communication system - Google Patents

Abstract

PURPOSE:To avoid the trouble of communication caused by soar noise that can be said as a fatal in satellite communication and to obtain a stable good quality communication circuit by providing plural ground stations and switching their satellite lines. CONSTITUTION:When the sun SUN enters in the beam of an antenna ANT installed in a ground station ARS and the trouble of communication due to the solar noise is anticipated wile a subscriber SUB is communicating using a satellite line 3 from the ground station ARS through a channel 1 of an international exchange EX, the international exchange EX switches to a channel 2 to use the satellite line 4 of the ground station ARS and a communication satellite 4. When it is anticipated that the satellite line 4 may suffer from the trouble of communication due to the solar noise with the lapse of time, the channel 2 switched by the international exchange EX is returned again to the channel 1, and the satellite line is also returned from 4 to 3. Here, the satellite line is changed by switching the channels and connection to the ground station by the international exchange EX. however, the channels may be switched between ground stations ARS.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention provides a method for setting up a satellite communication line using a geostationary satellite. This relates to a satellite communication system that solves the problem of communication being cut off due to solar noise.

[Background of the invention]

Traditionally, international communication lines installed in developing countries have often been constructed using the d/4 Insaki frequency, which uses geostationary satellites. This 6/43 band frequency has low rainfall attenuation and there is no need to consider line quality due to rain, so there is no need to install a night diversity ground station that can be switched as a backup ground station in the event of a ground station failure. . This means that when the sun comes on the line that connects the beam of the ground station antenna and the geostationary satellite, the quality of the communication line will be adversely affected by the influence of solar noise. There are some things that cannot be done. Even if reserve satellites are prepared for the geostationary satellite service, the reserve satellites used for international connections are configured to be switched over when the main satellite becomes obstructed, so the ground station happens to be exposed to the negative effects of solar noise. Even if such a problem occurs, there is no way to switch to the backup satellite's line, and the adverse effects of solar noise result in a temporary interruption of busy communication lines. In addition to some image transmissions, traditional telephone transmissions have been replaced by data communications, baggage, and other communications, which require retransmission of information when a line disconnection occurs, so instant line disconnections do not occur. The need for a satellite link system is desired.

2.As related to this type of technology, Japanese Patent Application Laid-open No. 5
There is a publication No. 9-138133.

[Purpose of the invention]

The purpose of the present invention is to construct a communication circuit using geostationary satellites.
This system solves the problem of line disconnections at ground stations due to solar noise and provides a high-quality communication line.

[Summary of the invention]

In satellite communication using a geostationary satellite, the present invention installs a plurality of ground stations at a distance that allows the beam of the ground station antenna to be set so that each ground station and upper station do not receive communication interference due to solar noise at the same time. When a communication failure due to solar noise is predicted to occur during satellite communication at one ground station, the communication failure due to solar noise in satellite communication can be prevented by switching the other ground station receiving system a without momentary interruption in advance. It's something you try to avoid.

[Embodiments of the invention]

FIG. 3 shows an example of an international communication line using conventional geostationary satellites, where SUB is a subscriber, EX is an international exchange, Al1 is a ground station, ANT is an antenna, SAT is a communication satellite, and SUN is the sun. In FIG. 3, subscriber SUB connects to communication satellite SAT from ground station AR8 via international exchange BX't.
When the sun SUN enters the beam of the antenna ANT installed on the ground station AR8K, the ground station is equipped with a parametric and amplifier to perform low noise amplification. is receiving a weak signal radio wave. For this reason, solar noise is orders of magnitude higher than the system noise temperature of a normal ground station receiving system, and the signal-to-noise ratio (S/
N ratio) decreases, making communication impossible. In other words, the satellite communication line becomes disconnected. Since the time when such communication failures due to solar noise will occur can be predicted in advance, when that time approaches, the line will be set up by switching to another ground station installed to avoid such communication failures.
The present invention will be explained in detail with reference to FIG. In FIG. 1, 1.2 is a channel within the international exchange, and 3.4 is a satellite line. Subscriber SUB is channel/L of international exchange EX
If the sun SUN enters the beam of the antenna ANT installed on the ground station AR8 during communication using the satellite line 3 from the ground station AR8 via /1, and a communication failure due to solar noise is predicted, Switch to channel 2 at the international exchange EX, and switch to use channel 4 for the satellite link between ground station AR8 and communication satellite SAT. Next, if it is predicted that the satellite ls4 will suffer communication interference due to solar noise as time passes, the international exchange EX will switch from channel 2 to channel 1 again.
and the satellite line from 4 to 3. In Figure 1, the satellite line was switched by switching the channel at the international exchange EX and switching the connection with the ground station K, but when the ground station AR
The lines may be switched between the 8 lines.

In developing countries, etc., where it is not possible to install multiple ground stations AR8 due to economic reasons, or when it is impossible to switch to an international line using an undersea coupler, it is possible to connect between neighboring countries. The technology of the present invention can also be applied when switching one satellite line. This example is explained in the second example.
As shown in the figure. If there is a prediction that a satellite line in your own country will experience communication problems due to solar noise, switch the line to an international exchange in a neighboring country in advance. Then, once the communication failure due to solar noise has been resolved, the line will be restored to its original state, and by doing so between neighboring countries, the busy technology of the present invention can be applied as is.

〔Effect of the invention〕

As described above, the present invention provides satellite communication MK using communication satellites.
By installing multiple ground stations and switching the satellite lines, the ground station can avoid communication problems caused by solar noise, which is the fate of satellite communications. This has the effect of providing a stable communication line with good quality.

[Brief explanation of the drawing]

FIGS. 1 and 2 are block diagrams showing an example of constructing a communication port Is using a geostationary satellite according to an embodiment of the present invention, and FIG. 3 is an explanatory diagram of a conventional communication line using a geostationary satellite. SUB...Subscriber, EX...International exchange island, AR8...Ground station, ANT...Antenna, SAT...Communication satellite, SUN...Sun, 1.2...Channel, 3 .4 Satellite link.

Claims (1)

[Claims] 1. In satellite communications using geostationary satellites, the beams of the ground station antennas can be set so that multiple ground stations can switch lines without instantaneous interruption, and each ground station does not receive communication interference due to solar noise at the same time. If a communication failure due to solar noise is expected during satellite communication between one of the multiple ground stations and a geostationary satellite installed at a distance, the communication line should be switched to another ground station in advance. Avoid communication failure due to solar noise, and then, if it is predicted that the communication line using the other ground station will suffer communication failure due to solar noise, switch back to the communication line with the original ground station. A satellite communication method that is characterized by