JPH042206A - On-vehicle satellite communication equipment - Google Patents

Abstract

PURPOSE:To apply automatic tracking of an antenna to a satellite by receiving reference signals from plural position measurement satellites, measuring the time difference among the reference signals to obtain position information of a satellite communication equipment and obtaining an azimuth angle, an elevating angle and a polarized wave angle to an object satellite. CONSTITUTION:Reference signals from three (1st-3rd) position measurement satellites 15-17 are received by a position measurement antenna 18, a time difference among the reference signals is measured, position information (latitude and longitude) of a communication equipment is calculated from the measured value and outputted. Then the azimuth angle, the elevating angle and the polarized wave angle are calculated by a monitor controller based on the name of an object satellite 1, the latitude and longitude and the calculated position information and the calculated information is fed to an antenna controller 10. The antenna controller 10 activates a motor 14 based on the information to drive the antenna 2. Thus, the antenna is directed to the satellite easily and correctly and the automatic tracking of the antenna is attained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a satellite communication device as a vehicle-mounted station, and particularly to a vehicle-mounted satellite communication device equipped with a tracking antenna device that automatically tracks the antenna by directing the antenna toward the satellite. Regarding.

[Prior Art] FIG. 2 shows the configuration of a conventional vehicle-mounted satellite communication device for transmitting and receiving TV signals. In the figure, 1 is a satellite, and 2 is an antenna of a communication device. The transmission side of this communication device includes a modulation device 3 that modulates the TV signal, a frequency conversion device 4 that converts the modulated signal to a transmission frequency, and a power amplification device 5 that amplifies the power of the transmission signal. The antenna 2 transmits the amplified signal to the target satellite 1.

In addition, the receiver that receives the signal transmitted from the satellite 1 includes a low-noise frequency converter 6 that amplifies the received signal and converts the frequency, a receiving frequency converter 7 that converts the signal to an intermediate frequency, and a frequency converter 6 that amplifies the received signal and converts the frequency. It has a demodulator 8 that demodulates the converted signal into a TV signal.

By the way, in order to transmit or receive a signal from the antenna 2, it is necessary to accurately point the antenna 2 in the direction of the target satellite. For this reason, conventionally, satellite 1
The azimuth and elevation angles are calculated from the position of the vehicle and the position of the in-vehicle satellite communication device read from the map, and based on the obtained angles, the antenna is manually driven while monitoring the AGC voltage obtained from the demodulator. to set its angle and capture the satellite.

[Problem to be solved by the invention]

However, this method has the problem that the azimuth and elevation angles must be recalculated each time the vehicle-mounted satellite communication device is moved, making the work complicated and time-consuming. Additionally, where the vehicle is tilted, the antenna will also be tilted, making calculations even more complicated.
In addition to making satellite acquisition difficult, there is also the problem that polarization adjustment takes time.

An object of the present invention is to provide a vehicle-mounted satellite communication device that can automatically track an antenna to a satellite.

[Means to solve the problem]

The satellite communication device of the present invention includes a positioning antenna that receives reference signals respectively output from a plurality of positioning satellites, and measures the time difference between each received reference signal, and determines position information of the satellite communication device from this time difference. A monitoring and control device that calculates the azimuth, elevation, and polarization angle of the satellite from the obtained position information and the target satellite name, etc., and a transmitting and receiving antenna based on the output of this monitoring and control device. and an antenna control device for directing the satellite XL in the opposite direction.

Preferably, it also includes a geomagnetic detector that detects the heading direction and declination angle from the north of the vehicle equipped with the satellite communication device, and a level sensor that detects the inclination angle of the vehicle. The azimuth angle, elevation angle, and polarization angle are corrected, and the corrected angles are sent to the antenna control device to correct the antenna direction.

Furthermore, it is also possible to receive a signal from a target satellite and send the AGC voltage obtained from the received signal to the antenna control device to automatically track the stencil track.

Effect C] According to the present invention, position information of a satellite communication device can be obtained by measuring the time difference between reference signals from a plurality of positioning satellites, and the azimuth angle, elevation angle, and polarization with respect to the target satellite can be obtained. You can find the angle.

Furthermore, the azimuth angle, elevation angle, and polarization angle associated with the azimuth and inclination angle of the vehicle can be corrected using the geomagnetic detector and the level sensor.

Furthermore, by using the AGC voltage of the receiving system, automatic tracking of the antenna becomes possible.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, and shows an example in which the present invention is applied to the vehicle-mounted satellite communication device that transmits and receives TV signals shown in FIG. Note that the same parts as in FIG. 2 are given the same reference numerals.

That is, 1 is a satellite, 2 is an antenna, and the transmission system is a modulator 3. Transmission frequency conversion device 4. It consists of a power amplification device 5, and a receiving system includes a low noise frequency conversion device 6. Reception frequency conversion device 7. It consists of a demodulator 8.

In such a vehicle-mounted satellite communication device, in the present invention, a plurality of positioning satellites 15, here three, first to third positioning satellites 15,
Positioning antenna 1 that receives the reference signal from 16.17
There are 8. A reference signal transmitted from a base station (not shown) is transmitted from the positioning satellites 15, 16, and 17, and this reference signal is received by the positioning antenna 18.

A low noise frequency converter 19 that converts the frequency of the received signal, a receiver 20 that demodulates the received signal, and a clock 21 that measures the time of the demodulated signal are connected to the positioning antenna 18. It is possible to measure the time difference between the respective reference signals from the positioning satellites 15°, 16.17, calculate the position information (latitude, longitude) of the communication device from this measured value, and output it.

In addition, the azimuth, elevation, and polarization angle are calculated based on the name of the target satellite 1, its latitude, and longitude inputted from the color display touch panel (not shown), and the calculated position information. A supervisory control device 9 is provided and sends this calculated information to an antenna control device 10. Based on this information, the antenna control device 10 operates the motor 14 via the motor control panel 13 to drive the antenna 2.

On the other hand, a geomagnetic detector 11 is provided to detect the direction of the vehicle's head and the declination angle from the north of the vehicle equipped with the satellite communication device, and a level sensor 12 is provided to detect the body inclination angle of the vehicle. is output to the antenna control device 10.

Note that the AGC voltage from the demodulator 8 of the receiving system is input to this antenna control device 10.

According to this configuration, the positioning antenna 18 receives reference signals from the three positioning satellites 15, 16, and 17, the time difference between each reference signal is measured by the clock 21, and the required calculations are performed. Location information of a communication device can be determined.

Then, this position information and the azimuth, elevation, and polarization angle of the target satellite calculated by the monitoring and control device 9 are sent to the antenna control device 10.

At the same time, the direction of the vehicle head and the declination angle from the north detected by the geomagnetic detector 11 are detected, coordinate conversion is performed to correct the azimuth angle, and the direction of the vehicle body detected by the level sensor 12 is also detected. The azimuth angle, elevation angle, and polarization angle are corrected based on the inclination angle. Then, information on each correction angle is sent to the antenna control device 10.

The antenna control device IO includes the monitoring control device 9, the geomagnetic detector 11. Based on the information input from the level sensor 12, the true azimuth, elevation, and polarization angle are calculated, and the results are sent to the motor control panel 13, which moves the motor 14 to direct the antenna 2 in the direction of the satellite 1. .

Furthermore, after pointing the antenna 2 toward the satellite 1,
By capturing the radio waves from the satellite 1, sending the AGC voltage obtained from the demodulator 8 to the antenna control device 10, and performing stenbu tracking, the maximum level of the signal from the satellite 1 is captured, making it a complete automatic tracking antenna device. be able to.

Note that the clock 21 is assumed to be a highly accurate clock in order to accurately synchronize the clocks of the in-vehicle station and the positioning satellite, but if the clock has low precision, four positioning satellites are required.

[Effects of the Invention] As explained above, the present invention can obtain the position information of a satellite communication device by receiving reference signals from a plurality of positioning satellites and measuring the time difference between these reference signals, and You can determine the azimuth, elevation, and polarization angle of the target satellite, so you can align the antenna correctly with respect to the satellite.
Moreover, it can be easily directed.

In addition, by detecting the vehicle's azimuth and inclination angle using a geomagnetic detector and level sensor, the azimuth and elevation angles can be determined.

It is also possible to correct the polarization angle.

Furthermore, by using the AGC voltage of the receiving system for steering and trunking, there is also the effect of enabling automatic tracking of the antenna.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional vehicle-mounted satellite communication device. 1...Satellite, 2...Antenna, 3...Modulator,
4... Transmission frequency conversion device, 5... Power amplifier device,
6...Low noise frequency conversion device, 7...Reception frequency conversion device, 8...Demodulation device, 9...Monitoring control device, 1
0... Antenna control device, 11... Geomagnetism detector,
12...Level sensor, 13...Motor control panel, 1
4...Motor, 15.16.17...Positioning satellite, 1
8... Positioning antenna, 19... Low noise frequency converter, 20... Receiver, 21... Clock. Diagram

Claims (1)

[Claims] 1. A positioning antenna that receives reference signals respectively output from a plurality of positioning satellites and a time difference between each received reference signal is measured, and position information of a satellite communication device is determined from this time difference. A monitoring and control device that calculates the azimuth, elevation, and polarization angle of the satellite from the obtained position information and the target satellite name, etc., and a transmitting and receiving antenna based on the output of this monitoring and control device. An in-vehicle satellite communication device comprising: an antenna control device that directs the antenna toward the satellite; 2. Equipped with a geomagnetic detector that detects the heading direction and declination angle from the north of a vehicle equipped with a satellite communication device, and a level sensor that detects the inclination angle of the vehicle, and calculates the azimuth and angle based on each of the detected values. 2. The vehicle-mounted satellite communication device according to claim 1, wherein the angle of elevation and the angle of polarization are corrected, and the corrected angles are sent to the antenna control device to correct the antenna direction. 3. Receiving a signal from a target satellite and transmitting an AGC voltage obtained from the received signal to the antenna control device to automatically track the step track.
The vehicle-mounted satellite communication device described in Section 1.