JP3237129B2 - CS converter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CS converter used for receiving a CS broadcast.

[0002]

2. Description of the Related Art In the near future, satellite broadcasting will include CS broadcasting using a communication satellite in addition to the current BS broadcasting. The radio waves of BS broadcasting are circularly polarized waves, whereas the radio waves of CS broadcasting are linearly polarized waves.
Broadcast can be sent.

[0003] A CS broadcast receiving system is provided by providing a CS antenna and a CS converter outdoors, providing a receiver indoors, and connecting the CS converter and the receiver via a signal cable. The CS converter simultaneously captures vertically and horizontally polarized waves collected by the CS antenna, respectively, and converts each of the captured signals to a predetermined frequency.

Here, if both the vertically polarized signal and the horizontally polarized signal are transmitted to the receiver, two signal cables are required. Generally, in order to receive VHF, UHF and BS broadcasts in addition to CS broadcasts, it is desirable that the number of signal cables guided indoors is as small as possible. Therefore, it is preferable that the CS converter and the receiver are connected only by one signal cable, and the vertical polarization signal and the horizontal polarization signal are selectively transmitted.

[0005]

However, since a CS converter selectively outputs a vertically polarized signal and a horizontally polarized signal according to a control signal from a receiver, a plurality of receivers share the CS converter. In this case, each receiver can receive only the same broadcast, and cannot receive different broadcasts independently.

Accordingly, the present invention provides a CS converter which connects a plurality of receivers with a single signal cable, and which can separately and independently transmit different broadcast signals to each receiver. Make it an issue.

[0007]

To achieve the above object, a CS converter according to the present invention comprises two orthogonal types.
First and second signals for receiving a horizontally polarized signal and a vertically polarized signal
Signal receiving unit, and the horizontal polarization signal and the vertical polarization signal
First and second conversion units for converting to a constant frequency;
A plurality of switches for selectively switching the signal output of the second converter
And the horizontal polarization signal and the vertical polarization signal.
The magnitude of the power supply voltage supplied corresponding to the
Corresponding to the detection result of the first conversion unit or the second conversion unit
The power supply voltage is selectively supplied to the conversion unit, and the
Outputs a control signal to selectively switch the number of changeover switches
Independent converter power detection for each receiver
And an output circuit.

[0008]

The converter power supply detection circuit detects the detected power supply voltage.
Before the first converter or the second converter corresponding to the size of
The power supply voltage is selectively supplied. When an arbitrary receiver sends a control signal via a signal cable, a corresponding changeover switch is switched to select a desired output of the conversion section based on the control signal, and each changeover switch is switched from a corresponding receiver. Are respectively switched by the control signals of.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show an embodiment of the present invention. This embodiment shows an example in which the present invention is applied to a system capable of receiving both a BS broadcast and a CS broadcast.

FIG. 2 is a schematic block diagram of a satellite broadcast receiving system. In FIG. 2, a radio wave focused by a BS antenna 1 is taken into a BS converter 2, which converts an input BS signal into a predetermined frequency and outputs it to a distributor 4 via a signal cable 3. The distributor 4 divides the BS signal into two systems, and each of the divided BS signals is connected to two BS / CS receivers 7 via each signal cable 5, 6.
a and 7b.

The radio wave focused by the CS antenna 8 is taken into the CS converter 9 and the detailed structure of the CS converter is shown in FIG. The output signal of the CS converter 9 is transmitted via the two signal cables 10 and 11 to each of the BS /
It is led to CS receivers 7a and 7b, respectively.

Each BS / CS receiver 7a, 7b has a BS / C
An S selection switch is provided. When the BS broadcast is selected by this switch, it is connected to the BS converter 2 via the signal cables 3, 5 and 6, and when the CS broadcast is selected by the switch, the CS converter 9 is provided via the signal cables 10 and 11. And a converter power supply.

The BS / CS receivers 7a and 7b are H /
A V selection switch, and when this switch selects horizontal polarization broadcasting, the voltage level of the converter power supply is set to 15V.
When the broadcast of the vertical polarization is selected, the voltage level of the converter power supply is output as 11V.

FIG. 1 is a circuit block diagram of the CS converter 9. In FIG. 1, two input probes 12 and 13 are arranged orthogonally in a waveguide, and one input probe 12 emits a horizontally polarized wave and the other input probe 1
Numeral 3 picks up vertically polarized waves. The outputs of the input probes 12 and 13 are guided to the conversion units 14 and 15, respectively.

Each of the converters 14 and 15 has an RF amplifier 16, a mixer 17 and an IF amplifier 18, and a local oscillation signal of a local oscillator 19 is input to both mixers 17. The horizontal polarization signal and the vertical polarization signal amplified by each RF amplifier 16 are converted into an intermediate frequency signal by each mixer 17, and the converted horizontal polarization signal and vertical polarization signal are amplified by each IF amplifier 18. Is done.

The outputs of the converters 14 and 15, ie, the horizontal polarization signal and the vertical polarization signal, are led to the two changeover switches SWa and SWb, respectively.
One of Wb is selectively supplied to each of the output terminals Ta and Tb based on the switching control signal.

The two signal cables 10 and 11 are connected to the output terminals Ta and Tb, respectively. The converter power supplied through the signal cables 10 and 11 is a power supply circuit 20 and a corresponding converter power supply. It is guided to the detection circuits 21a and 21b.

Each converter power supply detection circuit 21a, 21b
Detects the voltage level of the converter power supply, and outputs an H signal when the voltage is 15 V (when the horizontally polarized wave is selected) and an L signal when the voltage is 11 V (when the vertically polarized wave is selected). Output to the switches SWa and SWb.

The power supply circuit 20 supplies power to the converters 14 and 15 and the local oscillator 19 and the like. When one of the converter power supply detection circuits 21a and 21b outputs an H signal, the converter for horizontal polarization is used. 14, and when one of the converter power detection circuits 21a and 21b outputs an L signal, the power is supplied to the vertical polarization converter 15.
The local oscillator 19 is always supplied with power if converter power is supplied from the BS / CS receivers 7a and 7b. Each of the changeover switches SWa and SWb switches so as to select the output of the horizontal polarization converter 14 when the H signal is output and the output of the converter 15 for the vertical polarization when the L signal is output.

The operation of the above configuration will be described below.
Operate one BS / CS receiver 7a (or 7b) to set C
If you select S broadcast and select horizontally polarized broadcast,
A 15 V converter power supply is sent from the BS / CS receiver 7 a (or 7 b) to the CS converter 9. Then, the converter power supply detection circuit 21a (or 21b) outputs an H signal, the power supply circuit 20 supplies power to the horizontal polarization conversion unit 14, and the changeover switch SWa (or SWb) sets the horizontal polarization conversion unit. 14 output side (H terminal side).
Therefore, the horizontal polarization signal picked up by the input probe 12 is converted into a horizontal polarization signal of an intermediate frequency by the conversion unit 14, and the converted horizontal polarization signal passes through the changeover switch SWa (or SWb) and is transmitted to the signal cable 10. (Or 11) to the BS / CS receiver 7a (or 7b).

When the BS broadcast is selected by operating each of the BS / CS receivers 7a and 7b and the broadcast of the horizontal polarization is selected together, a 15V converter is provided from each BS / CS receiver 7a and 7b. Power is sent to the CS converter 9 together. Then, each converter power supply detecting circuit 21a, 2
1b both output an H signal, and each changeover switch SWa, S
Wb selects both the output side (H terminal side) of the conversion unit 14 for horizontal polarization, and the BS /
A horizontally polarized signal is supplied to the CS receivers 7a and 7b.

In this state, when the selection of one BS / CS receiver 7a (or 7b) is converted into a vertically polarized broadcast, the converter power supplied by one BS / CS receiver 7a (or 7b) becomes The level is changed to 11V. Then
Converter power supply detection circuit 21a (or 21b) outputs an L signal to power supply circuit 20 and corresponding changeover switch SWa (or SWb). The power supply circuit 20 also starts to supply power to the vertical polarization converter 15 and the corresponding switch S
Wa (or SWb) switches the connection to the output side (L terminal side) of the converter 15 for vertical polarization.

Accordingly, the vertical polarization signal processed by the vertical polarization converter 15 is supplied to the switch SWa (or SWb).
Through the signal cable 10 (or 11)
The horizontal polarization signal sent to the S / CS receiver 7a (or 7b) and processed by the horizontal polarization conversion unit 14 passes through the changeover switch SWb (or SWa) and is sent to the signal cable 11 (or 1).
0) via the other BS / CS receiver 7b (or 7a)
Sent to

In this embodiment, the case where two BS / CS receivers 7a and 7b are connected has been described.
As shown by virtual lines, three or more BS / CS receivers 7a, 7b,... Are connected by similarly adding changeover switches SWc,. Each of the BS / CS receivers 7a, 7b,... Can independently view different broadcasts.

In this embodiment, the BS / CS receiver 7
a, 7b, a switch SW to be sent to the CS converter 9
Although the control signals a and SWb also serve as the converter power supply and have their voltage levels, they may be configured as pulse signals to be transmitted while being superimposed on the converter power supply. In this case, a pulse decoder is provided instead of converter power supply detection circuits 21a and 21b, and power supply circuit 20 and changeover switches SWa and SWb are controlled by the pulse decoder.

In this embodiment, a receiver capable of receiving both a BS broadcast and a CS broadcast is used as a receiver. However, a receiver capable of receiving only a CS broadcast or receiving both a VHF broadcast and a UHF broadcast can be used. good.

[0027]

As described above, according to the present invention, two types of orthogonally polarized horizontal and vertical polarized signals are received.
First and second signal receiving units, the horizontal polarization signal and the vertical
First and second converters for converting a polarization signal into a predetermined frequency
And selectively outputting signal outputs of the first and second converters.
A plurality of changeover switches for switching, the horizontal polarization signal and
The magnitude of the power supply voltage supplied corresponding to the vertical polarization signal
And the first conversion unit corresponds to the detection result.
Alternatively, the power supply voltage is selectively supplied to the second conversion unit.
And selectively switches the plurality of changeover switches.
A plurality of independent controllers for each of a plurality of receivers that output control signals
And an inverter power detection circuit, so that each of the plurality of receivers is connected with one signal cable,
In addition, there is an effect that signals of different broadcasts can be transmitted to the respective receivers independently.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram of a CS converter (example).

FIG. 2 is a schematic configuration diagram of a satellite broadcast receiving system (embodiment);

[Explanation of symbols]

3, 5, 6, 10, 11 ... signal cables, 7a, 7b ...
BS / CS receiver (receiver), SWa, SWb, SWc
... changeover switch, 9 ... CS converter, 14, 15 ... converter.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model 62-133484 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 7/10 H04N 7/14-7 / 173 H04N 7/20-7/22

Claims (1)

(57) [Claims] 1. An orthogonal two horizontally polarized signal and a vertically polarized signal.
First and second signal receiving units for receiving the wave signals, converting the horizontal polarization signal and the vertical polarization signal to predetermined frequencies.
And first and second converters for switching, and selectively outputting signal outputs of the first and second converters.
A plurality of changeover switches for changing the horizontal polarization signal and the vertical polarization signal.
The magnitude of the power supply voltage detected, and respond to the detection result.
To the first converter or the second converter.
Pressure, and said plurality of changeover switches
For each of a plurality of receivers that output control signals for selective switching
CS converter characterized by comprising a plurality of converter power supply detection circuit independent, to.