JPH06105252A - Satellite receiver - Google Patents

Abstract

(57) [Abstract] [Purpose] A decoder is shared between receivers of different broadcasting systems. [Structure] When the externally connected receiver is a CS tuner, the video signal is changed to B
In the case of the S tuner, the detection signal is taken out. One of the signal derived from the changeover switch 8 and the signal supplied from the receiver connected to the outside is selected by the changeover switch 6, output from the terminal 7b, and processed by the decoder 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite broadcasting receiver, and particularly to a television broadcasting using a broadcasting satellite or a communication satellite.
The present invention relates to a satellite broadcast receiver suitable for selective reception.

[0002]

2. Description of the Related Art Television broadcasting using broadcasting satellites and communication satellites has been carried out. In these television broadcasting, however, the sending side of the television signal is generally scrambled in many cases. . Therefore, in order to view a television broadcast using a broadcasting satellite or a communication satellite, the scramble applied to the television signal must be released by a decoder.

A conventional system for receiving satellite broadcasting is shown in FIG.
Is shown in. As shown in FIG. 3, the SHF signal received by the satellite broadcasting antenna 41 is converted into a first intermediate frequency signal BSIF by a BS converter (not shown), and the first intermediate frequency signal is converted into a BS tuner. 42, and is supplied to the VTR 43 with a built-in BS tuner.

In the BS tuner 42 and the VTR 43, the above-mentioned first intermediate frequency signal BSIF is converted into a detection signal and a bit stream signal. The detection signal and the bit stream signal output from the VTR 43 and the BS tuner 4
One of the detection signal and the bitstream signal obtained in 2 is selected and supplied to the decoder 44.

In the decoder 44, the above-mentioned scramble is released, and from the detected signal and the bit stream signal,
A video signal and an audio signal are formed. By supplying the video signal and the audio signal to the monitor television 45, the television broadcast can be viewed.

The structure of the BS tuner 42 is shown in FIG. The SHF signal received by the antenna 41 is converted into the first intermediate frequency signal BSIF, and is supplied to the channel selection FM demodulation unit 52 via the terminal 51.

In the tuning FM demodulator 52, the tuning control microprocessor 55 selects a signal of a desired channel to form a detection signal. The detected signal is supplied to the video demodulation unit 53, the audio demodulation unit 54, and the terminal 56a of the changeover switch 56.

The video demodulation section 53 demodulates the detected signal to obtain a video signal. This video signal is taken out as a video output via the terminal 59. Also, the voice demodulation unit 5
In 4, the detected signal is QPSK demodulated under the control of the tuning control microprocessor 55 to obtain a bit stream signal and a voice signal. This bit stream signal is supplied to the terminal 56d of the changeover switch 56, and the audio signal is taken out as an audio output via the terminals 60a and 60b.

Under the control of the channel selection control microprocessor 55, the changeover switch 56 has terminals 56a-5.
The connection states of 6c and 56d to 56f are switched. As a result, a detection signal and a bit stream signal supplied from an externally connected receiver, for example, a VTR 43 with a built-in BS tuner, and a detection signal and a sound demodulation unit supplied from a channel selection FM demodulation unit 52 of the BS tuner 42. One of the bit stream signals supplied from 54 is selected.

As a result, the signal supplied to the decoder 44 is selected from the signal from the BS tuner 42 or the signal from the VTR 43 having an external BS tuner. That is, the detection signal supplied from the channel selection FM demodulation unit 52 is supplied to the terminal 56a, and the terminal 56b.
Is supplied with a detection signal from an external receiver via a terminal 57a, and the selected detection signal is supplied to a terminal 56c,
It is output via 57b.

Further, the bit stream signal supplied from the audio demodulation unit 54 is supplied to the terminal 56d, and the terminal 56d.
The bit stream signal supplied from the external receiver via the terminal 58a is supplied to e, and the selected bit stream signal is output via the terminals 56f and 58b.

[0012]

As described above, in order to receive and watch a television broadcast using a broadcasting satellite or a communication satellite, the scramble applied to the television signal must be descrambling by the decoder. However, if one decoder is to be shared by a plurality of types of satellite broadcasting receivers, the broadcasting system must be the same.

For example, satellite broadcasting receivers, for example, BS
When the tuner 42 and the VTR 43 with a built-in BS tuner are connected, it is possible to share one decoder. However, when the broadcasting systems are different, for example, a receiver for broadcasting by a broadcasting satellite (hereinafter, referred to as BS broadcasting) and a receiver for broadcasting by a communication satellite (hereinafter, referred to as CS broadcasting) are connected to each other to provide one decoder. However, there is a problem that there are many constraints and it is difficult to share. This is because the modulation degree of the signal is different even if the scrambling method is the same.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a satellite broadcast receiver in which a decoder can be shared by receivers of different broadcasting systems. .

[0015]

In order to solve the above-mentioned problems, the present invention separates a demodulation signal from a received signal and demodulates it, and a video signal from the detection signal to demodulate it. A second demodulation means, a third demodulation means for separating an audio signal from the detected signal and demodulating it to form a bit stream, a derived signal and a video signal, and selectively selecting one of the detected signal and the video signal. A first switching means for extracting the first signal, an input terminal for inputting a first signal supplied from an external device, and a second signal for selectively extracting one of the signal selected by the first switching means and the first signal. The switching means is provided.

[0016]

[Operation] The first signal is supplied to the input terminal from the external device. On the other hand, the detection signal is separated from the signal received by the antenna by the first demodulation means. A video signal is separated from the detected signal by a second demodulation means and demodulated, and
The audio signal is separated and demodulated by the third demodulation means. The third demodulation means separates and demodulates the audio signal and forms a bitstream signal.

The first switching means switches between the detection signal and the video signal according to the type of external equipment connected. For example, a detection signal is selected when the connected external device is a satellite broadcast receiver, and a video signal is selected when the connected external device is a communication satellite broadcast receiver. And
The signal selected by the first switching unit and the signal from the connected external device are selected by the second switching unit and output to the outside.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. Note that the BS tuner is described in this embodiment.

The structure of the BS tuner 1 is shown in FIG. The SHF signal received by the antenna 21 is converted into the first intermediate frequency signal BSIF and supplied to the channel selection FM demodulation unit 2 via the terminal 11.

In the channel selection FM demodulation unit 2, the channel selection control microprocessor 5 selects a signal of a desired channel to form a detection signal. The detected signal is supplied to the video demodulation unit 3, the audio demodulation unit 4, and the terminal 8a of the changeover switch 8.

The video demodulation section 3 demodulates the detected signal to obtain a video signal. This video signal is supplied to the terminal 8b of the changeover switch 8 and taken out via the terminal 9 as a video output. Also, in the voice demodulation unit 4,
Under the control of the tuning control microprocessor 5, the detected signal is QPSK demodulated to obtain a bit stream signal and a voice signal. This bit stream signal is supplied to the terminal 6d of the changeover switch 6, and the audio signal is supplied to the terminal 1
It is taken out as an audio output via 0a and 10b.

In the changeover switch 8, the connection state is controlled under the control of the tuning control microprocessor 5 by the operation of a key switch (not shown) by the user. That is, the detection signal output from the selected FM demodulator 2 and the video demodulator 3
And a video signal output from. The terminal 8c of the changeover switch 8 has a changeover switch 6
Is connected to the terminal 6a of the changeover switch 8 and the signal selected by the changeover switch 8 is supplied to the terminal 6a of the changeover switch 6.

Under the control of the channel selection control microprocessor 5, the change-over switch 6 has terminals 6a to 6c, 6a.
The connection state of d to 6f is switched. As a result, a video signal and a bit stream signal supplied from an externally connected receiver, for example, a CS tuner 23 described later, and a detection signal and an audio demodulation supplied from the channel selection FM demodulation unit 2 of the BS tuner 1. One of the bit stream signals supplied from the unit 4 is selected and output to the outside.

The tuning control microprocessor 5 controls the operation of the BS tuner 1. A key switch (not shown) is connected to the channel selection control microprocessor 5, and a control operation is performed based on a command input by a user operating the key switch. A control signal from the tuning control microprocessor 5 is a tuning FM demodulation unit 2, a voice demodulation unit 4, and changeover switches 6 and 8.
Etc., which controls the operation of each circuit block.

Next, the operation will be described with reference to FIGS. FIG. 2 shows an example in which the CS tuner 23 is connected to the BS tuner 1, and 22 is a CS antenna connected to the CS tuner 23. Figure 2
As shown in, the S received by the BS antenna 21
The HF signal is converted into a first intermediate frequency signal BSIF, BS
It is supplied to the channel selection FM demodulation unit 2 of the tuner 1.

In the selected FM demodulation section 2, a detection signal of a desired channel is formed, and the detection signal is sent to the video demodulation section 3,
The voice demodulation unit 4 and the terminal 8a of the changeover switch 8
Is supplied to. In the video demodulation unit 3, the detected signal is demodulated to obtain a video signal, which is supplied to the terminal 8b of the changeover switch 8 and taken out as a video output via the terminal 9. In the audio demodulation unit 4, the detected signal is QPSK demodulated to obtain a bit stream signal and an audio signal, the bit stream signal is supplied to the terminal 6d of the changeover switch 6, and the audio signal is supplied to the terminal 10.
It is taken out as an audio output via a and 10b.

The changeover switch 8 is brought into a connected state corresponding to a receiver connected to the outside by operating a key switch (not shown) by the user. For example, when the receiver connected to the outside is the CS tuner 23, the terminal 8
b and 8c are connected so that a video signal can be taken out, and in the case of a VTR with a built-in BS tuner, terminals 8a and 8c are connected so that a detection signal can be taken out. The signal extracted from the changeover switch 8 is supplied to the terminal 6 a of the changeover switch 6.

On the other hand, the receiver connected to the outside is CS
In the case of the tuner 23, the video signal is supplied to the terminal 6b via the terminal 7a, and in the case of a VTR with a built-in BS tuner, the detection signal is supplied to the terminal 6b via the terminal 7a. In addition, the bit stream signal is
Is supplied to the terminal 6e via.

Under the control of the tuning control microprocessor 5, the connection state of the changeover switch 6 is controlled. That is, one of (detection signal / video signal) and bit stream signal obtained inside the BS tuner 1 and (detection signal / video signal) and bit stream signal supplied from an externally connected receiver. Is selected and output to the outside.

A video signal or a detection signal is supplied to the decoder 24 from the terminal 7b of the BS tuner 1, and a bit stream signal is supplied to the decoder 24 from the terminal 8b. That is, when the receiver connected to the outside is the CS tuner, the video signal and the bit stream signal are supplied to the decoder 24, and when the receiver is the BS tuner, the detection signal and the bit stream signal are supplied to the decoder 24. It

Whether BS broadcasting or CS broadcasting,
Since the demodulated video signals are the same, the decoder 24 can be shared. For example, the radio wave of BS broadcasting is 15
The energy spread signal of Hz is superposed, resulting in 600K
The frequency deviation of the carrier wave of Hz is generated.
Further, an energy spread signal of 60 Hz is superimposed on the radio waves of CS broadcasting, which causes a frequency deviation of the carrier of 3 MHz.

In the decoder 24, descramble and other necessary processing are performed to form a video signal and an audio signal. By supplying the video signal and the audio signal to the monitor television 25, the monitor television 25 can view them.

As described above, according to one embodiment, when the receiver connected to the outside is the CS tuner, the changeover switch 8 extracts the video signal, and in the case of the BS tuner, the changeover switch 8 detects the detection signal. Is taken out. A signal derived from the changeover switch 8,
One of the signals supplied from the receiver connected to the outside is selected by the changeover switch 6 and output from the terminal 7b. Further, the bit stream signal is output from the terminal 8b via the changeover switch 6. CS tuner 23
Video signal and BS tuner 1
Since the video signal and the bit stream signal supplied from and demodulated are the same, they can be directly processed by the decoder 24 and can be viewed on the monitor television 25.

Therefore, when receiving and viewing a television broadcast having a different broadcasting system, for example, a television broadcast using a broadcast satellite and a communication satellite, one decoder 24 is set to B.
It can be shared by the S tuner 1 and the CS tuner 23. As a result, when receiving and viewing a television broadcast using a broadcasting satellite and a communication satellite, the receiving system can be made common to some extent, and the operability can be improved.
It can be further improved.

[0035]

According to the present invention, when receiving and viewing a television broadcast having a different broadcasting system, for example, a television broadcast using a broadcasting satellite and a communication satellite, one decoder is used as a BS tuner and a CS tuner. There is an effect that it can be shared in. As a result, when receiving and viewing a television broadcast using a broadcasting satellite and a communication satellite, the receiving system can be shared to some extent and the operability can be further improved. There is an effect.

[Brief description of drawings]

FIG. 1 is a block diagram of a BS tuner according to the present invention.

FIG. 2 is a diagram showing a television broadcast receiving system using a broadcast satellite and a communication satellite.

FIG. 3 is an explanatory diagram of a conventional example showing a television broadcast receiving system using a broadcast satellite.

FIG. 4 is a block diagram of a conventional BS tuner.

[Explanation of symbols]

 1, 42 BS tuner 2, 52 Channel selection FM demodulation unit 3, 53 Video demodulation unit 4, 54 Audio demodulation unit 6, 8, 56 Changeover switch 7a, 57a Terminal 23 CS tuner 24, 44 Decoder 43 VTR

Claims (1)

[Claims] 1. A first demodulation means for separating and demodulating a detection signal from a received signal, a second demodulation means for separating and demodulating a video signal from the detection signal, and an audio signal from the detection signal. A third demodulation means for separating and demodulating the signal to form a bit stream; a first switching means for deriving the detection signal and the video signal and selectively extracting one of the detection signal and the video signal; and an external device. An input terminal for inputting a first signal supplied from the device, and a second switching means for selectively extracting one of the signal selected by the first switching means and the first signal. Characteristic satellite broadcasting receiver.