JPS62279737A - Control device for plane of polarization of satellite broadcast receiving antenna - Google Patents

Abstract

PURPOSE:To effectively control the plane of polarization of an antenna by pushing either of switches for switching the plane of polarization, outputting data controlling it to an angle of horizontal and vertical plane of plarization from a microcomputer, D/A converting it to drive a pulse motor and rotating the antenna. CONSTITUTION:When either of switches 14 and 15 is pushed, the data which controls the antenna to the angle of horizontal or vertical plane of polarization is outputted from a microcomputer 13 and inputted in the register 18 of a D/A converter 17. Meanwhile in an oscillation circuit 19, for instance, 455 kHz signal is oscillated and transmitted to a counter 20. Then by means of a coincidence circuit 21, the pulse width is controlled as a low-frequency pulse which is in a necessary period to control a pulse motor with the data in the register 18 and outputted, transmitted to the pulse motor through a pulse output circuit 25 to control the antenna to the angle of horizontal or vertical plane of polarization.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention ``Field of Industrial Application'' The present invention is a satellite broadcasting receiving system for controlling the reception polarization plane of an antenna when changing the receiving satellite or channel. The invention relates to a device.

"Prior Art" First, an outline of a satellite broadcasting television receiver will be explained. Currently, in the United States, more than 20 private broadcasting geostationary satellites are being launched at intervals of 2 to 5 degrees, and each can be received using a television receiver equipped with an antenna position control device as shown in Figure 2. are doing. In this figure 2,
(1) is the reflector of the parabolic antenna, and this reflector (1)
A feed horn (2) is installed at the focal point of the feed horn (2), and a low noise amplifier and Dallan converter (3) coupled to the feed horn (2) are coupled to a satellite receiver (4) by a cable. A monitor TV (5), an audio device (6), and an antenna positioner (7) are coupled to this receiver (4), and the audio device (6) includes:
The left and right speakers (9) (10) are connected via the audio amplifier (8).
) are combined. Moreover, the antenna positioner
(7) is coupled to the feedhorn (2) and an actuator (12) for pointing to the position of the geostationary satellite (11).

Here, when a certain satellite (11) is selected by the antenna positioner (7), a DC control signal is generated in the motor drive section according to a command from the CPU in the antenna positioner (7), and this signal is transmitted to the actuator ( 12), and the rotation of this DC motor directs the parabolic antenna reflector (1) toward the target satellite.

At this time, pulses are generated in synchronization with the rotation of the DC motor, and the pulses are sent to the CPU via the pulse receiving section in the antenna positioner (7), and counted by the CPU.

This number of pulses determines the current position of the antenna and allows it to be moved to a preset satellite position. Furthermore, each satellite is equipped with 24 channels, so
Select one of the channels using the antenna positioner (7).

In the satellite broadcasting receiving system as described above.

To avoid interference, the transmission is alternately switched 90 degrees between vertically polarized waves and horizontally polarized waves for each channel, and in order to receive this, the feed horn (2) is equipped with a It is necessary to provide a polarizer. Some polarizers use a pulse motor to control the angle of the plane of polarization, and the so-called skew circuit used to control this pulse motor has conventionally used a pulse generation circuit to change the pulse width. Ta.

``Problems to be solved by the invention'' However, conventional pulse generation circuits have a large number of parts.
There were other problems, such as the need for adjustment for each unit, and the characteristics easily changing depending on the surrounding temperature.

"Means for Solving the Problems" The present invention has been made to solve the above-mentioned problems, and it is possible to change the pulse width of the pulse generation circuit applied to the pulse motor to improve the reception of satellite broadcast antennas. A satellite broadcasting receiver that controls the angle of the plane of polarization includes a microcontroller that combines a video and audio channel control remote control with horizontal and vertical polarization control switches, and a A digital-to-analog (D/A) converter as the pulse generation circuit for obtaining a pulse-width output, an oscillation circuit that is combined with this D/A run converter, and a pulse of the D/A run converter to be used as the pulse motor. It consists of a pulse output circuit that outputs to.

"Operation" When the horizontal polarization or vertical polarization switch connected to the microcomputer is pressed, the data is converted via the microcomputer into a D/A run converter as a pulse generation circuit. This D/A
The run converter oscillation circuit oscillates at a constant frequency,
The pulse width of this oscillation frequency is controlled based on the data from the microcomputer to the pulse width specified by the D/A run converter and output, and this pulse signal passes through the pulse output circuit and controls the pulse motor to produce the desired polarization plane. Control.

"Example" An embodiment of the present invention will be described below with reference to FIG.

(13) is the antenna positioner (7) in Figure 2.
This microcontroller (13) includes a switch (14) that controls the antenna to the horizontal polarization angle (or the pulse motor in the positive direction), and a switch (14) that controls the antenna to the vertical polarization angle (or A switch (15) for controlling the pulse motor (in the reverse direction) is connected thereto, and input terminals (16) for receiving satellite detection signals, channel selection signals, audio mode signals, etc. from the remote controller are also connected. A digital/analog (D/A) converter (17) serving as a pulse generating circuit is coupled to the output side of this microcomputer (13).

This D/A run converter 7) includes a register (18) that stores data from the microcomputer (13), and an oscillation circuit (
The matching circuit (21) consists of a counter (20) that counts pulses from the register (19) and a matching circuit (21) for the outputs of the register (18) and the counter (20). 22) and resistance (23) (24)
The output terminal (26) of this pulse output circuit (25) is connected to the pulse motor in the feed horn (2) in FIG. 2.

In the above configuration, the switch (14) (t5
), the microcomputer (13) outputs data for controlling the angle of the plane of polarization, horizontal or vertical, and inputs it to the register (18) of the D/A converter (17). The oscillation circuit (19) oscillates a signal of, for example, 455 KHz, and this signal is sent to the counter (20). Then, the width of the pulse is controlled by the minus number circuit (21) using the data in the register (18) as a low frequency pulse with a period of about 0.5 to 2.2 m5ec, which is necessary to control the pulse motor, and output. . This pulse is transmitted to the pulse output circuit (25
) and is sent to a pulse motor to control the angle of the antenna horizontally or vertically.

"Effects of the Invention" Since the present invention is configured as described above, the number of parts is greatly reduced to 1710 or less compared to the conventional pulse generation circuit.
Further, since no adjustment is required and no special parts are used, there is an effect of significant cost reduction.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a polarization plane control device for a satellite broadcast receiving antenna according to the present invention, and FIG. 2 is a block diagram of a satellite broadcast receiving system. (1)...Reflector, (2)...Feed horn, (
3)...Low noise amplifier and down converter, (4
)...Receiver, (5)...Monitor TV, (6)...
・Audio device, (7)...Antenna positioner-1 (9
) (10)...Speaker, (11)...Satellite,
(12)...actuator, (13)...microcomputer, (14) (15)...polarization plane switching switch,
(16)...Input terminal, (17)...D/A converter, (18)...Register, (19)...
Oscillation circuit, (20)...counter, (21)...-
Several circuits, (22)...transistors, (23) (2
4)...Resistor, (25)...Pulse output circuit, (2
6)...Output terminal.

Claims (2)

[Claims] (1) In a satellite broadcasting receiver that controls the angle of the receiving polarization plane of the satellite broadcasting antenna by varying the pulse width of the pulse generator circuit applied to the pulse motor, the video and audio channel control remote control and the horizontal polarization A microcomputer that combines a wave and vertical polarization control switch, a digital-to-analog converter as the pulse generation circuit for obtaining an output with a pulse width corresponding to data from the microcomputer, and a digital-to-analog converter for this digital-to-analog converter. A polarization plane control device for a satellite broadcasting antenna, comprising a coupled oscillation circuit and a pulse output circuit that outputs pulses from the digital-to-analog converter to the pulse motor. (2) The digital-to-analog converter as a pulse generation circuit consists of a register that stores data from the microcomputer, a counter that reduces the oscillation output of the oscillation circuit to a low pulse, and a matching circuit that obtains a matching output from these registers and the counter. A polarization plane control device for a satellite broadcast receiving antenna according to claim 1.