CN210576462U

CN210576462U - Automatic satellite alignment control system for vehicle-mounted satellite antenna

Info

Publication number: CN210576462U
Application number: CN201921973221.1U
Authority: CN
Inventors: 冉莉; 王峰
Original assignee: Nanjing University of Information Science and Technology
Current assignee: Shanghai Changxing Information Technology Co ltd
Priority date: 2019-11-15
Filing date: 2019-11-15
Publication date: 2020-05-19
Anticipated expiration: 2029-11-15

Abstract

The utility model discloses an automatic satellite alignment control system of a vehicle-mounted satellite antenna, which consists of a central controller, a GPS module, an electronic compass, an inclination angle sensor, a recovery position switch, an extreme position switch, a motor driving module, a satellite receiving module and a USB interface circuit module; the central controller is a control and data processing center of the system, and control information is displayed through upper computer software; a serial port RS232 collects data of the tilt angle sensor and the GPS to obtain position coordinates of the antenna carrier; the motor driving module drives the antenna to rotate to the position of the satellite. The utility model discloses on-vehicle satellite antenna is automatic to star control system through application operation processing ability powerful control system and paster chip, has carried out miniaturized design, has realized that the accuracy is still less, the higher effect of positioning accuracy to star, location update and positioning time. And a high-precision tilt angle sensor is adopted to further measure the pitch angle parameter, so that the measurement precision is improved.

Description

Automatic satellite alignment control system for vehicle-mounted satellite antenna

Technical Field

The utility model relates to an automatic to star control system, especially relate to automatic to star control system of on-vehicle satellite antenna.

Background

The satellite communication is not affected by region limitation and severe weather, and has the advantages of wide coverage and high reliability. The vehicle-mounted satellite station has the characteristics of small volume, flexible movement, low cost, convenient maintenance and the like, and is widely applied to the fields of various emergency communications, live news broadcast, military command and the like.

Foreign countries such as Raysat corporation in Israel, KVH corporation in the United states, Wiworld corporation in Korea, and NKH corporation in Japan have already developed relatively sophisticated vehicular satellite communication solutions and are widely used in military and commercial fields. However, since the technology is kept secret, only the profile of the product is available, and the products of these manufacturers are expensive.

The domestic vehicle-mounted satellite communication technology starts late, is not mature compared with the domestic vehicle-mounted satellite communication technology, and has certain achievements in recent years, but the automatic satellite-alignment control system of the domestic vehicle-mounted satellite antenna generally has the problems of complex system, huge equipment and higher cost.

SUMMERY OF THE UTILITY MODEL

Utility model purpose: in order to solve the problems existing in the prior art, the utility model provides a miniaturized, low-cost, quick accurate automatic to star control system of on-vehicle satellite antenna.

The technical scheme is as follows: the utility model discloses an automatic satellite alignment control system of a vehicle-mounted satellite antenna consists of a central controller, a GPS module, an electronic compass, a tilt angle sensor, a recovery position switch, a limit position switch, a motor driving module, a satellite receiving module and a USB interface circuit module; the central controller is a control and data processing center of the system, and control information is displayed through upper computer software; acquiring data of an inclination angle sensor and a GPS (global positioning system) through a serial port RS232 to obtain an inclination angle of an antenna carrier, namely a mobile vehicle and a position coordinate of the mobile vehicle in a geographic coordinate system; converting the azimuth angle, the pitch angle and the polarization angle of the satellite in the geographic coordinate system into three large angles in an antenna carrier-mobile vehicle coordinate system through a coordinate transformation algorithm; then the system judges whether the antenna is aligned to the satellite by continuously scanning the satellite television signal strength output by the DVB-S2 tuner in the satellite receiving module; and a satellite position and speed closed loop PID algorithm is adopted to control the motor to drive the antenna to rotate to the position of the satellite, so that accurate satellite alignment is realized.

The system positioning uses a GS-92m-j chip, is a module packaged by a super-small-volume patch, has the size of 13 × 16 × 2.6mm, is updated for 1 second in positioning, has the positioning time less than 1 second, and has the positioning precision of 2.5 meters.

The electronic compass adopts an LIS3MDL meaning semiconductor three-axis magnetometer chip to communicate with a controller STM32F446 through an I2C serial bus, and is used for collecting the azimuth angle, the pitch angle and the roll angle of the antenna carrier. And further measuring the pitch angle parameter by using an American Measurement Accstar high-precision tilt angle sensor.

Firstly, positioning the longitude and latitude of the location of a vehicle-mounted satellite station through GS-92m-j in a GPS module, and calculating the azimuth angle, the pitch angle and the polarization angle of a satellite in a geographic coordinate system; because the mobile vehicle as an antenna carrier is influenced by various factors in the running process, in order to avoid yaw, pitch and roll and change the carrier attitude, the azimuth angle, the pitch angle and the polarization angle of the satellite are subjected to coordinate transformation and converted into corresponding angles under an antenna carrier coordinate system, and the vehicle-mounted satellite antenna automatic satellite alignment control system controls the antenna to rotate to the angle of the satellite, so that accurate satellite alignment is realized.

Has the advantages that: the utility model discloses on-vehicle satellite antenna is automatic to star control system through application operation processing ability powerful control system and paster chip, has carried out miniaturized design, has realized that the accuracy is still less, the higher effect of positioning accuracy to star, location update and positioning time. And a high-precision tilt angle sensor is adopted to further measure the pitch angle parameter, so that the measurement precision is improved.

Drawings

FIG. 1 is a block diagram of the system of the present invention;

FIG. 2 is a flow chart of a control algorithm of the present invention;

FIG. 3 shows a GPS module and its peripheral circuitry;

fig. 4 is a limit hall switch circuit of the present invention;

fig. 5 is a motor driving module of the present invention;

fig. 6 shows a satellite receiving module according to the present invention.

Detailed Description

The technical solution of the present invention is further explained with reference to the drawings and the specific examples.

As shown in fig. 3, in the GPS module and its peripheral circuits, the network labels GPS _ RX and GPS _ TX are serial data communication ports between the processor and the module, and the series resistors R16-R17 mainly improve impedance matching, reduce reflection, and avoid oscillation.

As shown in fig. 4, a limit hall switch is selected, and potentiometers are used as position feedback measurers in the control of a system azimuth motor and a polarization motor, and the potentiometers are respectively installed on an azimuth gear seat and a polarization gear seat. The potentiometer is driven to rotate by the azimuth and polarization gear to change the resistance value of the potentiometer, so that the voltage of 0 to +5V is changed and output, the output voltage is converted into a digital signal through A/D, and the central controller realizes the inspection of two angular positions by acquiring the digital signal.

The antenna rotation is set within a limit range for safety reasons. And limiting Hall switches are arranged at the extreme positions of the azimuth angle and the pitch angle, and once the antenna reaches the extreme positions, the limiting Hall switches stop the motor. The automatic satellite alignment control system of the vehicle-mounted satellite antenna uses 3 limit Hall switches which are respectively used for position protection and confirmation of antenna recovery, maximum pitching limit, azimuth limit and the like. The limit Hall switch is respectively connected with

pins

1, 3 and 5 of a Schmidt trigger 74HC14 chip through a voltage dividing resistor. When the switch is conducted, the network outputs 4.2V voltage; when the switch is disconnected, 0V voltage is output and is transformed into high and low logic levels compatible with the pins of the central controller through 74HC14 shaping. The central controller judges whether the antenna reaches the limit position or not through the on-off state of the limit Hall switch, once the antenna reaches the limit position, the limit Hall switch stops the motor, and meanwhile, the software can trigger limit warning to remind an operator to perform necessary treatment.

As shown in fig. 5, the motor driving module is mainly composed of an H-bridge driving circuit composed of an MC33883 chip and a power tube. When the motor needs to rotate forwards, the central controller sets the pin DIR to be at a high level, and then IN _ HS2 is at a high level; PWM and DIR are connected with a pin IN _ LS1 after passing through an AND gate A, and the pin IN _ LS1 is controlled by PWM. As can be seen from the truth table of the chip, the Gate _ HS2 is at high level, PWM controls the Gate _ LS1, the MOS transistor T2 is turned on, the 12V power current passes through the fuse F3, passes through the motor through the T2, and finally flows out from the T3, and the motor realizes forward rotation. Otherwise, the central controller sets DIR to be low level, and then the pin IN _ HS1 is high level; DIR is inverted and then connected with the PWM through an AND gate B and a pin IN _ LS2, and the pin IN _ LS2 is controlled by the PWM. According to a truth table of the chip, the Gate _ HS1 is in a high level, PWM controls the Gate _ LS2, the MOS transistor T1 is conducted, 12V power current passes through the motor through the T1 through the fuse F3, and finally flows out of the motor through the T4, so that the motor is reversed.

As shown in fig. 6, the satellite receiving module uses a satellite digital television network interface module SP2236SHb to communicate with STM32F446 over an I2C serial bus. The SP2236SHb integrates a satellite television signal tuner and a modem, an antenna receives satellite signals, the satellite signals are accessed to an RF _ IN end through a low noise down converter LNB, and the signals enter the SP2236SHb tuner. The tuner converts satellite television signals into digital signals, and the digital signals are demodulated into standard television video and audio signals through the modem and output by an RF _ OUT end. The central controller can obtain the signal-to-noise ratio value of the satellite signal in real time by reading the data of the S/N (signal-to-noise ratio) register unit of the satellite signal in the SP2236SHb, so as to judge the accuracy of the antenna to the satellite. The Tuner _ SCL is an I2C bus clock line, the Tuner _ SDA is an I2C bus data line, and two 100 Ω resistors connected in series on the bus can effectively suppress interference pulses on the bus from entering the slave device, thereby improving reliability. Two resistors of 4.7K are pull-up resistors of an I2C bus, the I2C protocol provides that the maximum allowable value of a port output low level is 0.4V, and according to practical use experience, the resistors of 4.7K are connected appropriately, so that the I2C bus can stably communicate.

The Asia satellite four is taken as an example, system tests are carried out, and the results show that the automatic satellite alignment control system of the vehicle-mounted satellite antenna can realize accurate satellite alignment within 3 minutes and can meet the requirement of actual movement on the satellite.

Claims

1. The utility model provides an automatic control system that aims at star of on-vehicle satellite antenna which characterized in that: the device consists of a central controller, a GPS module, an electronic compass, a tilt angle sensor, a recovery position switch, an extreme position switch, a motor driving module, a satellite receiving module and a USB interface circuit module; the central controller is a control and data processing center of the system, and control information is displayed through upper computer software; a serial port RS232 collects data of the tilt angle sensor and the GPS to obtain position coordinates of the antenna carrier; the motor driving module drives the antenna to rotate to the position of the satellite.

2. The automatic satellite-alignment control system of the vehicle-mounted satellite antenna according to claim 1, characterized in that: and a resistor is connected in series between the GPS module and the processor.

3. The automatic satellite-alignment control system of the vehicle-mounted satellite antenna according to claim 1, characterized in that: the electronic compass adopts a three-axis magnetometer chip and is communicated with the central controller through an I2C serial bus.

4. The automatic satellite-alignment control system of the vehicle-mounted satellite antenna according to claim 1, characterized in that: the motor driving module is composed of an H-bridge driving circuit composed of a chip and a power tube.

5. The automatic satellite-alignment control system of the vehicle-mounted satellite antenna according to claim 1, characterized in that: the satellite receiving module adopts a satellite digital television network interface module and carries out communication through an I2C serial bus.

6. The automatic satellite-to-satellite control system of the vehicle-mounted satellite antenna according to claim 5, characterized in that: the satellite receiving module comprises an I2C bus clock line and an I2C bus data line, and the bus clock line and the bus data line are respectively connected with a resistor in series.