JPH10210458A - Satellite changeover device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To switch and receive a radio wave from plural satellites with a single antenna system, without the use of an exclusive switching line by using a connection cable between the antenna system and a receiver to transmit a voltage for switching the satellite from the receiver to the antenna system. SOLUTION: Antenna systems 3, 4, receiving radio waves from plural satellites 1, 2 and receivers 5, 6 are connected by a single line and the receivers 5, 6 are provided with a power supply circuit that generates a power supply voltage for switching a polarized wave selecting a desired polarized wave of a reception radio wave corresponding to selection of a reception channel and a power supply voltage for switching a satellite to switch the satellite corresponding to a selected channel. The power supply voltage for switching the polarized wave and the voltage for switching the satellite are transmitted from the receivers 5, 6 through the single line to the antenna systems 3, 4 and the antenna systems 3, 4 switch the satellite upon the receipt of the voltage for switching the satellite from the receivers 5, 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite switching apparatus for switching and receiving radio waves from a plurality of satellites, and more particularly to a satellite switching apparatus for realizing, for example, PerfecTV! The present invention relates to a satellite switching apparatus, for example, in a case where radio waves from a communication satellite are switched and received by one television receiver at home.

In PerfecTV !, an attempt has been made to increase the number of programs to 150 channels or more. Correspondingly, there is a tendency for more satellites.

[0003]

2. Description of the Related Art Conventionally, at least in Japan, there has been no demand for switching and receiving radio waves from a plurality of satellites. In a vast area such as the United States, when receiving radio waves from multiple satellites, prepare multiple antenna devices corresponding to each of the satellites and change the output of the antenna device to a switching signal dedicated line from a switching box etc. , The required program is received by a television receiver, or the directivity angle of one antenna device is changed by a motor or the like to receive a radio wave from a target satellite.

[0004]

When a satellite is switched by using a switching dedicated signal from a switching box or the like as described above, a plurality of antenna devices and a switching box are required, so that the area occupied by them becomes large. In addition to the high cost, there is a problem that installation is difficult. In addition, since a dedicated signal line for a dedicated switching signal must be provided separately from a cable connecting the switching box and the television receiver, the number of signal lines between the antenna device and the television receiver increases. .
Therefore, there is a problem that the cost of the antenna device is increased and the installation work of the antenna device is complicated.

In order to change the directional angle of one antenna device, a driving device such as a motor is required, which not only increases the size of the antenna device but also increases the cost and the satellite. There is a problem that the time required for switching is too long, which is inconvenient for the user. The purpose of the present invention is
In view of the above problems in the prior art, the satellite switching voltage is transmitted from the receiver to the antenna device by using a connection cable between the antenna device and the receiver, so that a dedicated switching line is not used and the satellite switching voltage is simply used. An object of the present invention is to enable radio waves from a plurality of satellites to be switched and received by one antenna device.

[0006]

According to one aspect of the present invention, an antenna apparatus includes a voltage detection unit for determining a type of a voltage transmitted from a receiver and a changeover switch. When the voltage detection unit determines that the satellite switching voltage has been received from the receiver, it switches the received radio wave from the radio wave currently being received to the radio wave emitted by the other satellite, and transmits the radio wave to the receiver and the antenna device. There is provided a satellite switching device adapted to transmit via a single line connecting to a receiver.

[0007] This makes it possible to switch and receive radio waves from a plurality of satellites with a single antenna device without using a dedicated switching line. In the present invention, the satellite switching voltage has a different value from the polarization switching voltage. Further, the satellite switching voltage may have a predetermined pulse width, and the voltage detection unit may drive the switch to switch the satellite to be received when detecting the satellite switching voltage of the predetermined width. Good.

Alternatively, the satellite switching voltage has a different pulse width corresponding to each of the plurality of satellites, and the voltage detector has means for determining the pulse width of the satellite switching voltage. The switch may be driven to switch to the satellite corresponding to the determined pulse width. In another aspect, the satellite switching voltage has a number of pulses corresponding to each of the plurality of satellites within a predetermined period, and the voltage determination circuit counts the number of satellite switching voltage pulses within the predetermined period. May be provided, and the switch may be driven to switch to the satellite corresponding to the counted number of pulses.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a system configuration diagram showing an outline of the present invention. In FIG. 1, reference numerals 1 and 2 denote communication satellites (hereinafter simply referred to as satellites), reference numerals 3 and 4 denote antenna devices,
5 and 6 are television receivers. The satellite 1 is, for example, a geostationary satellite above 124 ° east longitude, and the satellite 2 is, for example, a geostationary satellite above 128 ° east longitude. Satellite 1 is, for example, 1
Responsible for broadcasting of ~ 150 channels, satellite 2 is an additional 1
Responsible for broadcasting on 10 channels. Satellites 1 and 2 are, for example, 500 from 12.25 GHz to 12.75 GHz.
Using a frequency band of MHz, radio waves of both vertically and horizontally polarized waves are transmitted toward the ground. The channel transmitted by the vertical polarization and the channel transmitted by the horizontal polarization are different from each other,
The number of channels that can be transmitted in this band is doubled compared to the case where no distinction is made by polarization.

The antenna device 3 includes two satellites 1 and 2
One antenna mirror surface 31 for receiving radio waves from the antennas, and antenna horns 32 and 3 respectively disposed at the focusing positions of the radio waves from the satellites 1 and 2 reflected by the mirror surface 31
3 and one LNB (Low Noise Block Converter) 34
, And the LNB 34 amplifies the received radio wave, converts the frequency, and delivers it to the television receiver. LNB34
Are two frequency converters 35 and 36 corresponding to the two satellites 1 and 2, respectively, and a changeover switch controller 37 for switching the output of the frequency converter by the power supply voltage from the receiver 5 and transmitting the output to the receiver 5. And

On the other hand, the antenna device 4 and the television receiver 6 are conventional ones that receive only radio waves from one communication satellite 2. The antenna device 4 includes one antenna mirror surface 41 and one LNB 42. The LNB 42 amplifies a received radio wave, converts the frequency thereof, and delivers it to a television receiver. FIG. 2 is a block diagram showing the antenna device 3 and the receiver 5 in FIG. 1 in detail. In FIG. 2, a first frequency converter 35 in an LNB 34 included in the antenna device 3 performs VH polarization switching for selectively outputting either horizontal polarization or vertical polarization from radio waves transmitted from the antenna horn 32. Unit 201, a high-frequency amplifier (RF amplifier) 202 for amplifying the output thereof, a band-pass filter (BPF) 203, and an oscillating frequency of a local oscillator 205 mixed with the output of the band-pass filter 203 to produce an intermediate frequency signal (for example, 1450 KHz) and I which amplifies the output of the mixer 204.
An F amplifier 206 is provided.

Similarly, the frequency conversion unit 36 includes a VH polarization switching unit 207 for selectively outputting either horizontal polarization or vertical polarization from the radio wave transmitted from the antenna horn 33,
High frequency amplifier (RF amplifier) 208 for amplifying the output
, A band-pass filter (BPF) 209, and a local oscillator 2
11 includes a mixer 210 that mixes the output of the bandpass filter 209 with the oscillation frequency of the mixer 11 and outputs an intermediate frequency signal, and an IF amplifier 212 that amplifies the output of the mixer 210.

The changeover switch control section 37 is controlled by a voltage detection section 213 for detecting a voltage transmitted from the receiver 5 and an output of the voltage detection section 213, and is controlled by the frequency conversion section 35.
Switch 214 for selecting any one of the outputs 36 and 36
And a capacitor 215 for cutting a DC component. The receiver 5 receives a signal from a power supply circuit 216, a receiver power supply circuit 217 for supplying a voltage at the time of satellite switching or a voltage corresponding to a received polarization, and a signal from a remote control unit (remote control) 218 to a designated channel. A receiving circuit 219 for outputting a corresponding signal, a satellite identification / polarization identifying circuit 220 for identifying a polarization to be selected at the time of satellite switching or to be selected according to an output signal from the receiving circuit 219, and a receiver power supply corresponding to the identification. Power supply control circuit 2 for controlling the
21, a capacitor 222 for cutting a DC component, and an amplifier 223.

The receiver 5 and the LNB 3 are connected to a connector 224
Single connection cable 22 connected between
6. Via this connection cable 226, the reception signal of either horizontal polarization or vertical polarization is L
The polarization selection voltage or the satellite switching voltage from the receiver power supply circuit 217 is transmitted from the NB 3 to the receiver 5. This polarization selection voltage or satellite switching voltage is applied to the voltage detection unit 213 in the LNB 3 via the line 227.

FIG. 3 is a block diagram showing an example of the configuration of the voltage detector 213 in the block diagram of FIG. In FIG. 3, a voltage switching unit 213 includes a satellite switching voltage detecting unit 301 connected to the line 227, a satellite switching control unit 302 controlled by the switching voltage detecting unit 301, a polarization switching voltage detecting unit 303, and a polarization switching voltage controlled by the satellite switching voltage detecting unit 303. The LNB 3 includes a wave switching control unit 304 and power supply units 305 connected to the line 227 to supply power to each unit in the LNB 3.

FIG. 4 is a circuit diagram showing a configuration example of the satellite switching voltage detecting section 301 in the block diagram of FIG. In FIG. 4, the satellite switching voltage detection unit 301 includes a first voltage comparator circuit 401, a comparison timer circuit 402, and a second voltage comparator circuit 403. Next, the operation of the circuit of FIG. 2 will be described with reference to the voltage time chart shown in FIG.

When the user selects a desired channel with the remote controller 218 or directly on the receiver, the receiving circuit 219 generates a signal corresponding to the channel and supplies it to the satellite identification / polarization identification circuit 220. Satellite identification
The polarization identification circuit 220 identifies the satellite emitting the radio wave of the selected channel and the polarization of the radio wave according to the signal. According to the identification result, the receiver power supply control circuit 221 controls the receiver power supply circuit 217 so as to generate a corresponding voltage. Thus, the receiver power supply circuit 217 generates a voltage (for example, 15 V or 11 V) according to the polarization when the satellite does not switch, and generates a voltage AV different from the voltage according to the polarization when the satellite switches. (For example, 5 V). The voltage is transmitted to the voltage detection unit 213 in the LNB 3 via the connection cable 226.

For example, the channel currently being received is satellite 1
If the signal is derived from a radio wave included in the vertical polarization from the VH, the VH polarization switching unit 201 is controlled by the voltage detection unit 213 receiving the voltage of 15 V from the receiver 5 to selectively output the vertical polarization. The switch 214 is controlled by the voltage detector 213 to transmit the output of the IF amplifier 206 to the receiver 5.

In this state, the user operates the remote control 218
When the user selects a channel by operating or by pressing the channel selection button on the receiver 5, the receiving circuit 219 generates a signal corresponding to the channel, and the satellite identification / polarization identification circuit 220 A corresponding reception state is identified, and the receiver power supply circuit 217 is controlled according to the state. As a result, the receiver power supply circuit 217 generates a voltage corresponding to the channel in response to the control signal.

If the satellite corresponding to the designated channel is also the satellite 1 and the polarization corresponding to the channel is also the vertical polarization, the receiver power supply circuit 217 directly generates the currently generated voltage of 15V. The control of the VH polarization switching unit 201 and the changeover switch 214 by the voltage detection unit 213 does not change. If the satellite corresponding to the designated channel is also satellite 1, but the polarization corresponding to that channel is horizontal polarization, the receiver power supply circuit 217 outputs the currently generated voltage of 15V.
Is changed to a voltage corresponding to horizontal polarization, for example, 11V.
When this voltage is transmitted to the voltage detector 213 in the LNB 3 via the connection cable 226, the voltage detector 213
The H-polarization switching unit 201 is controlled to selectively output the horizontal polarization, but the state of the switch 214 does not change.

When the satellite corresponding to the designated channel is the satellite 2, as shown in FIG. 5, the receiver power supply circuit 217 stops generating the currently generated voltage of 15 V, and switches the switching voltage AV (for example, 5 V). ) Is output. When this voltage is transmitted to the voltage detector 213 in the LNB 3 via the connection cable 226, the voltage detector 213
By detecting V, the switch 214 is switched to selectively output the output of the IF amplifier 212 in the frequency conversion unit 36 corresponding to the satellite 2. Thereafter, the receiver power supply circuit 217 in the receiver 5 generates a voltage (15 V or 11 V) corresponding to the polarization including the specified channel, and the voltage detection unit 213 detects this to detect the VH polarization. The switching unit 207 is controlled to output a polarization corresponding to the voltage.

As described above, according to the embodiment of the present invention, it is possible to easily switch the satellite only by specifying the channel by the user. More specifically, in the voltage detection unit 213, as shown in FIG. 3, the satellite switching voltage detection unit 301 controls the satellite switching control unit 302 when detecting the satellite switching voltage AV from the power supply voltage superimposed on the line 227. Then, the switch 214 is controlled. When detecting the voltage of 15V or 11V corresponding to the selected channel from the power supply voltage superimposed on the line 227, the polarization switching voltage detection unit 303 controls the polarization switching control unit 304 according to the voltage. VH polarization switching unit 201 or 20
7 to perform the polarization switching. Further, each unit power supply unit 305 converts the voltage supplied from the line 227 to the LNB3
Is applied to each part inside.

Further, in the satellite switching voltage detecting section 301,
As shown in FIG. 4, the first voltage comparator 401 compares the voltage on the line 227 with a threshold A, and outputs a trigger signal when the voltage is within the set voltage range of the satellite switching voltage AV ± α, The comparison timer circuit 402 outputs a voltage having a specified pulse width using the trigger signal as a trigger. When the trigger signal output from the first voltage comparator 401 and the voltage of the specified pulse width output from the comparison timer circuit 402 match within a predetermined range, the second voltage comparator 403 outputs a satellite switching signal to the line 227. When it is determined that voltage AV has been transmitted, satellite switching control section 302
, The receiving satellite is switched. That is, in order to further reliably detect the switching voltage, a period T1 of the voltage AV is determined in advance as shown in FIG. 5, and the satellite switching voltage detecting unit 301 determines the duration T1 of the voltage AV.
Is detected, the changeover switch 214 is controlled to switch the satellite.

By combining a plurality of such comparison timer units and voltage comparators, it is possible to switch in accordance with patterns having different pulse widths. For example, when the satellites are continuously switched, in order to ensure that the switching is performed, as shown in FIG. 6, a voltage for designating the polarization during two periods T1 of the continuous switching voltage AV (see FIG. 6). 1
The satellite may be switched only when the duration (5 V or 11 V) is equal to or longer than T2.

Further, when there are three or more satellites, FIG.
The switching from the currently selected satellite to the next satellite may be performed sequentially each time the switching voltage AV as shown in FIG. Further, when there are three or more satellites, as shown in FIG. 7, the number of pulses that become AV within a predetermined period T3 is counted,
A satellite corresponding to the number may be selected.

[0026]

As is clear from the above description, according to the present invention, a plurality of satellites can be transmitted from a plurality of satellites without using a dedicated switching line and providing simple switching means in a single antenna device. Can be switched and received.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an outline of the present invention.

FIG. 2 is a block diagram showing an antenna device and a receiver in FIG. 1 in detail.

FIG. 3 is a block diagram illustrating a configuration example of a voltage detection unit in FIG. 2;

FIG. 4 is a circuit diagram illustrating a configuration example of a satellite switching voltage detection unit in FIG. 3;

FIG. 5 is a voltage waveform diagram illustrating an operation according to one embodiment of the present invention.

FIG. 6 is a voltage waveform diagram illustrating an operation according to another embodiment of the present invention.

FIG. 7 is a voltage waveform diagram illustrating an operation according to still another embodiment of the present invention.

[Explanation of symbols]

 1, 2, satellite 3, 4, antenna device 5, 6, receiver 216, power supply circuit 213, voltage detector 214, changeover switch 217, channel selector 220, connection cable

Claims (8)

[Claims] An antenna device for converting and outputting the frequency of radio waves from a plurality of satellites, a receiver for receiving radio waves output from the antenna device, and a single device for connecting the antenna device and the receiver. A receiver, wherein the receiver comprises: a polarization switching power supply voltage for selecting a polarization including a reception channel selected by a user; and a satellite transmitting the selected reception channel which is currently selected. A power supply circuit for generating a satellite switching voltage for switching a satellite so as to receive a radio wave from a satellite transmitting the selected reception channel when the selected satellite is different from the selected satellite. The power supply voltage and the satellite switching voltage are transmitted from the receiver to the antenna device via the single line, and the antenna device is transmitted from the receiver. A voltage detection unit for determining the type of voltage, and a changeover switch, wherein the changeover switch is provided while the voltage detection unit determines that the polarization switching power supply voltage is being received from the receiver. When the frequency of the polarization corresponding to the polarization switching voltage is converted and transmitted to the receiver via the single line, and the voltage detection unit determines that the satellite switching voltage has been received from the receiver. A satellite switching device for switching a received radio wave from a radio wave currently being received to a radio wave emitted by another satellite and transmitting the radio wave to the receiver via the single line. 2. The satellite switching apparatus according to claim 1, wherein said satellite switching voltage has a value different from said polarization switching voltage. 3. The satellite switching device according to claim 2, wherein said satellite switching voltage has a predetermined pulse width. 4. The satellite switching device according to claim 2, wherein said satellite switching voltage has a different pulse width corresponding to each of said plurality of satellites. 5. The satellite switching apparatus according to claim 2, wherein the satellite switching voltage has a number of pulses corresponding to each of the plurality of satellites within a predetermined period. 6. The satellite switching device according to claim 3, wherein said voltage detecting section switches said satellite to be received by driving said changeover switch when detecting said satellite switching voltage of said predetermined width. apparatus. 7. The voltage detection unit includes means for determining a pulse width of the satellite switching voltage, and drives the switch to switch to a satellite corresponding to the determined pulse width. The satellite switching device according to claim 4. 8. The method according to claim 1, wherein the voltage detecting unit is configured to:
6. The satellite switching device according to claim 5, further comprising means for counting the number of pulses of the satellite switching voltage, wherein the switch is driven so as to switch to a satellite corresponding to the counted pulse number.