JPH04207332A - Satellite communication earth station - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to satellite communications, and particularly to antenna direction adjustment suitable for a small satellite communications earth station that is used in a portable manner.

[Conventional technology]

When installing the conventional portable satellite R7 earth station after it has been transported, check the position of the station on a map etc., measure the direction, and then set the latitude and longitude of the station and the latitude of the satellite to be used. The direction of the communication antenna was adjusted by calculating the longitude or by using a quick reference table.

[Problems to be Solved by the Invention] The above-mentioned conventional technology does not take into account the automation and facilitation of the direction adjustment of the communication antenna after the mobile installation of the earth station. It required specialized skills and a long time.For this reason, it took a long time to set up the necessary communication lines, making it unsuitable for emergency communications, news communications, etc. that require quick line setup. The problem was that there was no.

An object of the present invention is to automate the direction adjustment of a communication antenna after installation of a portable satellite communication earth station, or to facilitate the antenna direction adjustment by instructing the operator to adjust the antenna direction. Reduce communication line setup time,
Moreover, the purpose is to eliminate the need for operations by specialized engineers.

[Means to solve the problem]

The above purpose is to obtain accurate latitude, longitude, and altitude after the portable satellite communication earth station is installed from a positioning system using an artificial satellite, and to direct the communication antenna based on the azimuth and orbital position of the communication satellite. This can be achieved by measuring the direction W and controlling the direction of the communication antenna, or by displaying the direction to the operator.

[Effect]

Positioning systems that use artificial satellites place satellites in multiple fixed orbits around the earth. Each of these satellites is equipped with an accurate timer and transmits this time via radio waves. Positioning systems using artificial satellites are arranged so that multiple satellites can always be seen from any point on the earth. Since the orbits of these satellites are known, radio waves from multiple satellites are received, the distance to each satellite is determined from the arrival time of the 15th satellite, and a semicircle is drawn around each satellite. The exact latitude, longitude, and altitude of the receiving point can be determined from the intersection.

Now, the latitude of any point on the earth is ψ, and the longitude is ψ.

The position of the communication satellite is 1a degree ψ7. Longitude λ11. If the radius of the earth at an arbitrary point of altitude a is R, the angle Ef and azimuth A7 of the artificial satellite viewed from an arbitrary point are given by the following equations.

Here 0=cos' [sinψTsinψ→CO3ψT
COSψ, cos(λ n, )].

In addition, in the geostationary satellite H7 used for communication satellites,
Since the geostationary satellite takes an orbit on the equator, the latitude ψ of the communication satellite can be simplified to -0 degrees. The latitude of the point where the portable satellite communications earth station is to be transported and installed, obtained from the satellite-based positioning system;
The elevation angle E1 and the azimuth Az at which the communication antenna should be directed are determined from the longitude and altitude, and the latitude, longitude, and altitude of the known communication satellite.

In reality, it is necessary to take into account the unevenness of the earth, but it is possible to obtain it roughly as above.

By directing the antenna in the direction of the elevation angle E1 and azimuth Az of the communication satellite determined in this way, the direction of the antenna can be adjusted.

〔Example〕

Hereinafter, one embodiment of claim 1 of the present invention will be described with reference to FIG. 1 is a positioning satellite system]
S (G Q oba Q Positioning
2 is an antenna for receiving radio waves 100 from GPS satellites, 3 is a GPS receiver that calculates the position from the signal, and the obtained position information 2
00 is output to the computer 5. Direction information 300 measured by a direction measuring device 4 is output to a measuring device 5. Principles of GPS, a positioning satellite system, and GP
There are many documents regarding the S receiver, such as the Institute of Electronics, Information and Communication Engineers technical research report NIS 87-4 (
Please refer to SA, Ta2-4), etc.

A result 400 calculated by the computer 5 from the position information, azimuth information, and known satellite positions is output to the display device 6 and to the elevation angle control device 71\ as elevation angle information 500. Azimuth information 600 is output to an azimuth control device. Elevation angle control device 7 and azimuth angle control device 8 also use this information and output elevation angle control signal 700 and azimuth angle control information 800 to antenna drive device 9. The antenna driving device 9 drives the antenna 10 according to the information on the communication satellite 1.
Turn to 2.

At this time, a signal from another earth station, a return signal of a signal transmitted from the own station at the satellite, or a beacon wave 90 ( ) of the satellite itself is received. A signal 1000 received by the antenna 10 enters the satellite communication transceiver 11 and outputs received field strength information 1100 to the calculator 5.

Based on this received field strength information, the meter 5 controls the elevation angle control device 7 and the azimuth angle control device 8 to obtain a better reception condition, and eliminates positioning errors and the like. According to this embodiment, the antenna direction adjustment of the portable satellite communication earth station can be performed automatically and with high precision at any point on the earth.

Hereinafter, an embodiment of claim 2 will be explained based on the second factor. Signal from GPS satellite 1 of positioning satellite system]
00 is received by the GPS antenna 2, and the GPS
The signal is input to the receiver 3. The GPS receiver 3 receives location information 2
00 is output to the computer 5.

The direction measuring device 4 measures the direction and outputs direction information 300 to the computer 5. The computer 5 calculates the elevation angle and azimuth angle of the antenna from the position information 200, the azimuth information 300, and the position of the known communication satellite, and the result 400 is displayed on the display section W6. Based on this information, the operator manually adjusts the antenna direction using the antenna direction adjustment mechanism 13.

In order to further improve the accuracy of direction adjustment, one antenna 10 receives a signal from another earth station, a satellite return signal of a signal transmitted by the own station, or a beacon signal 900 transmitted by the satellite itself. Received th signal 1.0
00 is input to the satellite communication transceiver 11 and received
Received electric field strength information 1.100 corresponding to the knee strength is output to the received electric field strength display section 14. The operator further operates the antenna direction adjustment mechanism 13 so that the received field strength display section 14 indicates the maximum value. According to this embodiment, even in a simple portable satellite communication earth station that does not have an antenna drive device, it is possible to quickly and accurately adjust the angle direction.

〔Effect of the invention〕

According to the present invention, the adjustment of the antenna direction of the portable satellite communication earth station can be automated or facilitated, thereby reducing the time required for setting up the line of the portable satellite communication earth station and eliminating the need for specialized personnel.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing another embodiment. 1.GPS satellite 2..GPS receiving antenna 3..
・GPS receiver 4...Direction measuring device 65...
Meter device 6...Display device 7...Elevation angle control device 8...Azimuth angle control device 9...Antenna drive device 10...Communication antenna 11...Satellite communication transceiver 12... Communication satellite I3... Antenna direction adjustment mechanism 14... Received electric field strength display section 1 power? ~φ〆

Claims (1)

[Scope of Claims] 1. A satellite communication earth station characterized in that it obtains its own position information from a positioning system using artificial satellites and adjusts the direction of its antenna. 2. A satellite communications earth station characterized by obtaining its own position information from a positioning system using an artificial satellite and instructing the operator in the direction of the antenna based on this information. 3. A satellite communication earth station characterized in that claim 1 or 2 is mounted on a car, a ship, etc.