JPH08181968A - Satellite broadcast receiver - Google Patents

Abstract

PURPOSE: To allow another satellite broadcast receiver to use in common a built-in scramble decoder in a satellite broadcast receiver. CONSTITUTION: A detection signal from a BS front end 2 is given to a terminal (a) of a switch SW6 and a detection signal from another satellite broadcast receiver 105 is given to a terminal (b) of the switch SW6. A video signal outputted from a detection processing section 3b is given to a terminal (a) of a switch SW7 and a video signal outputted from a scramble decoder 200 is given to a terminal (b) of the switch SW7. A QPSK PCM demodulation circuit 4 extracts a voice signal and descrambles the voice signal simultaneously. When an external detection signal is descrambled, the switches SW6, 7 are thrown to the position of the terminal (b) and the video signal and the voice signal are fed from output terminals 14-16 to a satellite broadcast receiver 105.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite broadcast receiver incorporating a scramble decoder.

[0002]

2. Description of the Related Art In recent years, satellite broadcasting has come into widespread use, and not only ordinary free broadcasting but also pay scrambled broadcasting or high definition broadcasting by the MUSE system has come to be performed. Also, not only satellite broadcasting using broadcasting satellites, so-called BS broadcasting, but also satellite broadcasting using communication satellites, so-called CS broadcasting have come to be performed. Thus, satellite broadcasting is becoming more and more diversified.

FIG. 2 shows a configuration in which a conventional satellite broadcasting receiver and a scramble decoder for restoring a scrambled signal by scrambled broadcasting to a normal NTSC signal are connected. In FIG. 2, the broadcast wave received by the BS antenna 1 is converted into an IF signal and the satellite broadcast receiver 1
It is input to the BS front end 2 in 00. The BS front end 2 is composed of a channel selection circuit 2a and an FM demodulation circuit 2b. The channel selection circuit 2a extracts a channel signal selected from the input IF signal and outputs it to the FM demodulation circuit 2b.
Outputs the detected signal by FM demodulating the signal. The detection signal output from the FM demodulation circuit 2b is input to the video detection demodulation circuit 3, subjected to filtering and amplification processing, and then demodulated to extract the video signal.
In the video detection demodulation circuit 3, the audio subcarrier signal is separated at the same time. The demodulated video signal is input to the terminal a of the switch SW1, and the audio subcarrier signal is QPSK, PCM.
It is input to the demodulation circuit 4.

The QPSK / PCM demodulation circuit 4 QPSK-processes and PCM demodulates the input voice subcarrier signal to take out a digital voice signal. This digital audio signal is input to the D / A converter 5 to be an analog audio signal, which is input to the terminals a of the switches SW2 and SW3. Q
The output of the PSK, PCM demodulation circuit 4 is also input to a microcomputer (hereinafter abbreviated as microcomputer) 6. The microcomputer 6 detects a pay flag of the satellite broadcast signal and controls each unit in the satellite broadcast receiver 100. The detection signal that has been subjected to the filtering and amplification processing in the video detection demodulation circuit 3 is input to the detection input terminal 21 of the external scramble decoder 200 via the detection output terminal 9, and is input from the QPSK and PCM demodulation circuit 4. The output bitstream signal is input to the bitstream input terminal 22 of the scramble decoder 200 via the bitstream output terminal 10. The bit stream signal is a signal including data and audio signals for pay broadcasting contracts, non-contracts, and descrambles.

The video signal descrambled by the scramble decoder 200 is input to the video input terminal 11 of the satellite broadcast receiver 100 via the video output terminal 23.
The audio signal descrambled by the scramble decoder 200 is input to the audio input terminals 12 and 13 of the satellite broadcast receiver 100 via the audio output terminals 24 and 25.
In addition, these video input terminal 11 and audio input terminal 1
Reference numerals 2 and 13 are dedicated terminals for inputting a signal (return signal) after processing by an external device such as the scramble decoder 200, and are referred to as return input terminals.

The return signals input to the return input terminals 11 to 13 are input to the terminals b of the switches SW1 to SW3, respectively. Return input terminal (video input terminal) 1
The video signal input from 1 is also input to the signal detection circuit 7 to detect whether or not the scramble decoder 200 is connected. A signal output from the microcomputer 6 for detecting the pay flag and a signal output from the signal detection circuit 7 indicating that the scramble decoder 200 is connected are input to the AND circuit 9. The AND circuit 9 detects the pay flag by ANDing the input signals and outputs a high (H) signal when the scramble decoder 200 is connected. The H signal output from the AND circuit 9 causes the switches SW1 to SW3 to switch to the terminal b.
Switch to connect to.

Thus, when the scramble decoder 200 is a pay broadcast and the scramble decoder 200 is connected, an image automatically input from the external scramble decoder 200,
The audio signal can be selected. This function is called the auto return function. Then, the switches SW1 to SW1
The video and audio signals output from SW3 are supplied to a video and audio processing circuit (not shown).

By the way, a viewer who owns a plurality of satellite broadcast receivers, for example, a viewer who owns another satellite broadcast receiver in addition to the conventional satellite broadcast receiver 100 and the scramble decoder 200 shown in FIG. There is a demand for a person to view a scrambled broadcast by another satellite broadcast receiver. The scramble decoder 200 not only descrambles scrambled broadcasting by BS broadcasting,
Since it can also be used for descrambling scrambled broadcasting by some CS broadcasting, the above-mentioned demand is very strong for a viewer who has a plurality of satellite broadcasting receivers. In this case, the viewer has no choice but to prepare a scramble decoder different from the scramble decoder 200, or reconnect the scramble decoder 200 to another satellite broadcast receiver for use.

In order to solve this problem, therefore, there is a satellite broadcast receiver having a function that can be used for another satellite broadcast receiver without reconnecting the cable to the scramble decoder 200, that is, a so-called double decoder function. Proposed. FIG. 3 shows a configuration in which a satellite broadcast receiver 101 having a double decoder function, a scramble decoder 200, and another satellite broadcast receiver 102 are connected. In the satellite broadcast receiver 101 in FIG. 3, the same parts as those in the satellite broadcast receiver 100 in FIG.

The satellite broadcast receiver 101 shown in FIG. 3 differs from the satellite broadcast receiver 100 shown in FIG. 2 in that a detection input terminal 14, a bit stream input terminal 15, and switches SW4 and SW5 are newly provided. The detection signal output from the detection output terminal 31 of the satellite broadcast receiver 102 is the satellite broadcast receiver 1
01 is input to the detection input terminal 14 of the satellite broadcast receiver 1
The bit stream signal output from the bit stream output terminal 32 of No. 02 is input to the bit stream input terminal 15 of the satellite broadcast receiver 101. Similar to FIG. 2, the detection output terminal 9 and the bit stream output terminal 10 of the satellite broadcast receiver 101 are connected to the detection input terminal 21 and the bit stream input terminal 22 of the scramble decoder 200, respectively. Further, the video / audio output terminals 23 to 25 of the scramble decoder 200 are connected to the return input terminals 11 to 13 of the satellite broadcast receiver 101 as in FIG. 2, and the other video / audio output terminals 26 to 28 are connected to the satellite. It is connected to the return input terminals (or video input terminals) 33 to 35 of the broadcast receiver 102.

The fixed terminal of the switch SW4 is connected to the detection output terminal 9, the detection signal output from the video detection demodulation circuit 3 is input to the terminal a, and the terminal b is the detection input terminal 14
It is connected to the. The fixed terminal of the switch SW5 is connected to the bit stream output terminal 10, and the QPS is connected to the terminal a.
The bit stream signal output from the K, PCM demodulation circuit 4 is input, and the terminal b is the bit stream input terminal 1
Connected to 5. Then, when the viewer gives an instruction to switch to select the output of the satellite broadcast receiver 102 using, for example, a remote control transmitter, a selection signal S is input to the microcomputer 6, and the switches SW4 and SW5 switch the microcomputer 6 to each other.
It is connected to the terminal b under the control of. Then, the detection signal and the bit stream signal output from the satellite broadcast receiver 102 are input to the scramble decoder 200 via the switches SW4 and SW5. As a result, one scramble decoder 200 is connected to two satellite broadcast receivers 1
01, 102 can be shared.

The conventional satellite broadcast receivers 100 and 101 shown in FIGS. 2 and 3 described above are the scramble decoder 2
00 is not built in. Since the scramble decoder 200 is externally attached, the satellite broadcast receiver 1
Work such as cable connection between 00 and 101 and the scramble decoder 200 is complicated. Therefore, if a satellite broadcast receiver incorporating the scramble decoder 200 is used, this problem can be solved.

FIG. 4 shows the structure of the satellite broadcast receiver 103 having the scramble decoder 200 built therein. Here again, in the satellite broadcast receiver 103 in FIG. 4, the same parts as those in the satellite broadcast receivers 100 and 101 in FIGS. 2 and 3 are denoted by the same reference numerals, and the description of the common parts is omitted. In the configuration shown in FIG. 4, since the scramble decoder 200 is incorporated, the signal detection circuit 7 for detecting whether or not the scramble decoder 200 shown in FIG. 2 is connected is not necessary. Therefore, the AND circuit 9 is not necessary, and the switches SW1 to SW3 are directly switched by the signal output from the microcomputer 6 which detects the pay flag. The satellite broadcast receiver 103 shown in FIG. 4 realizes the above-described auto return function as an internal system. In addition, the viewer can view the scrambled broadcast simply by selecting a channel without performing work such as cable connection.

[0014]

However, in the satellite broadcast receiver 103 incorporating the scramble decoder 200 as shown in FIG. 4, the scramble decoder 2
Since 00 is dedicated to the satellite broadcast receiver 103, the scramble decoder 200 cannot be shared by the two satellite broadcast receivers like the double decoder function described in FIG. Since the new single scramble decoder 200 is required, not only the price of the main body but also the registration fee and the viewing fee are charged, so that the economic burden on the viewer is doubled.

The present invention has been made in view of the above problems, and in a satellite broadcast receiver having a scramble decoder built-in, the built-in scramble decoder can be shared by other satellite broadcast receivers. The purpose is to provide a receiver.

[0016]

In order to solve the above-mentioned problems of the prior art, the present invention provides a front end (2) for demodulating an input IF signal and outputting a detection signal, and the detection signal. A video detection demodulation circuit (3) for processing and extracting a video signal and separating an audio subcarrier signal, an audio signal output means (4, 5) for processing the audio subcarrier signal and extracting an audio signal, and the input. In the satellite broadcast receiver comprising a detection means (6) for detecting whether or not the IF signal thus obtained is a scrambled signal, and a scramble decoder (200) for descrambled the detection signal, the audio signal output means is provided. (4, 5) is used as an audio descrambling means for descrambling the audio signal when extracting the audio signal, and the scramble decoder (200) is A video descramble means for descramble the image signal, for outputting the video signal descrambled by the scramble decoder (200) and the audio signal output by the audio signal output means (4,5) to the outside. Video and audio output terminals (14 ~
16), a detection input terminal (17) for inputting a detection signal from the outside, and the IF input to one terminal.
The detection signal obtained from the signal is input, and the external detection signal input from the detection input terminal (17) is input to the other terminal, and these detection signals are selectively detected by the video detection demodulation circuit ( 3) and the first switching means (SW6) for supplying to the scramble decoder (200)
And a video signal output from the video detection demodulation circuit (3) is input to one terminal and a video signal output from the scramble decoder (200) is input to the other terminal. (SW7) and control means (6) for switching and controlling the first and second switching means (SW6, SW7) according to a detection signal or a selection signal from the detection means (6). The present invention provides a satellite broadcast receiver characterized by.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A satellite broadcast receiver according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing an embodiment of a satellite broadcast receiver of the present invention. In FIG. 1, the same parts as those in FIGS. 2 to 4 are designated by the same reference numerals.

In FIG. 1, the broadcast wave received by the BS antenna 1 is converted into an IF signal, and the satellite broadcast receiver 10
4 is input to the BS front end 2. The BS front end 2 is composed of a channel selection circuit 2a and an FM demodulation circuit 2b. The channel selection circuit 2a takes out a channel signal selected from an input IF signal, and an FM demodulation circuit 2b FM demodulates the signal. And outputs a detection signal. The detection signal output from the FM demodulation circuit 2b is the video detection demodulation circuit 3
Is input to The video detection / demodulation circuit 3 demodulates the input detection unit 3a for further filtering and amplification of the input detection signal, the switch SW6, and the detection signal output from the input processing unit 3a to extract the video signal and to output the audio signal. It is composed of a detection processing unit 3b for separating the subcarrier signal. The output of the switch SW6 is input to the detection processing unit 3b and the scramble decoder 200. Detection processing unit 3
The video signal demodulated by b is input to the terminal a of the switch SW7, and the audio subcarrier signal is input to the QPSK and PCM demodulation circuit 4.

The QPSK / PCM demodulation circuit 4 extracts the digital voice signal by QPSK processing and PCM demodulation of the input voice subcarrier signal. The QPSK and PCM demodulation circuit 4 also performs QPSK processing and PCM demodulation.
At the same time, the audio is descrambled. In the past, descrambling of voice was performed in the scramble decoder 200, but in the present invention, it is performed in the QPSK and PCM demodulation circuit 4. The descramble of the voice by the QPSK and PCM demodulation circuit 4 can use the conventional one as it is.
The cost does not increase. The descrambled digital audio signal output from the QPSK and PCM demodulation circuit 4 is input to the D / A converter 5 to be an analog audio signal, which is input to the audio output terminals 15 and 16.
It is supplied to an audio processing circuit (not shown).

The output of the QPSK and PCM demodulation circuit 4 is also input to the microcomputer 6. The microcomputer 6 detects a pay flag of the satellite broadcast signal and controls each unit in the satellite broadcast receiver 104. The descramble data output from the QPSK / PCM demodulation circuit 4 is input to the scramble decoder 200. Scramble decoder 2
The video signal descrambled by 00 is input to the video output terminal 14 and also to the terminal b of the switch SW7, and is supplied to a video processing circuit (not shown) in the subsequent stage.

The video and audio output terminals 14 to 16 of the satellite broadcast receiver 104 are connected to the return input terminals (or video input terminals) 41 to 43 of another satellite broadcast receiver 105, and the detection output of the satellite broadcast receiver 105 is detected. The terminal 44 is connected to the detection input terminal 17 of the satellite broadcast receiver 104.
The detection signal obtained in the satellite broadcast receiver 105 is transmitted through the detection output terminal 44 and the detection input terminal 17 to the switch SW6.
Is input to the terminal b. Then, the switches SW6 and SW
7 is switched as follows to realize a so-called double decoder function in which the scramble decoder 200 is shared by the two satellite broadcast receivers 104 and 105.

That is, in a normal free scrambled broadcast, the switches SW6 and SW7 are both connected to the terminal a. For scrambled pay broadcasting, the microcomputer 6 detects the pay flag and switches the switch SW7 to connect to the terminal b so that the microcomputer 6 outputs the video signal output from the scramble decoder 200. On the other hand, the viewer transmits the detection signal obtained by the satellite broadcast receiver 105 to the satellite broadcast receiver 104.
In order to descramble with the built-in scramble decoder 200, for example, when an instruction to switch to select the double decoder function is given by the remote control transmitter, the selection signal S is input to the microcomputer 6 and the switch S is input.
Both W6 and SW7 are connected to the terminal b under the control of the microcomputer 6.

Thus, in the case of pay broadcasting, a so-called auto-return function that can automatically obtain a signal descrambled by the scramble decoder 200 is realized and the built-in scramble decoder 20 is provided.
Even if it is 0, this is set to two satellite broadcasting receivers 104, 1
The so-called double decoder function, which is shared by 05, is realized. In the satellite broadcast receiver 104 of the present invention, the connection with the satellite broadcast receiver 105 is such that the QPSK and PCM demodulation circuit 4 descrambles the voice, and therefore the cable for the detection signal and the return input signal after descramble Only the cables for the video and audio signals required for are required, and the cables for the bit stream signals, which were required in the past, are not required.

[0024]

As described above in detail, in the satellite broadcast receiver of the present invention, the audio signal output means is the audio descrambling means for descramble the audio signal when the audio signal is taken out. The built-in scramble decoder is used as the video descramble means for descramble the video signal, and the video and audio for outputting the video signal descrambled by the scramble decoder and the audio signal output from the audio signal output means to the outside. An output terminal, a detection input terminal for inputting a detection signal from the outside, a detection signal obtained from the input IF signal is input to one terminal, and a detection input terminal is input to the other terminal. External detection signals are input, and these detection signals are selectively supplied to the video detection demodulation circuit and scramble decoder. And a second switching means to which the video signal output from the video detection demodulation circuit is input to one terminal and the video signal output from the scramble decoder is input to the other terminal. ,
Since the control means for switching and controlling the first and second switching means in accordance with the detection signal or the selection signal by the detection means is provided, it is possible to automatically obtain a decrambled signal in the case of pay broadcasting. , The built-in scramble decoder can be shared by different satellite receivers. Further, according to the present invention, the connection with another satellite broadcasting receiver inputs the cable for the detection signal from the other satellite broadcasting receiver and the return input signal after descrambling to the other satellite broadcasting receiver. Since only the cables for the video and audio signals are required and the cables for the bit stream signals are not required, the complexity of wiring can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a block diagram showing a conventional example.

FIG. 3 is a block diagram showing a conventional example.

FIG. 4 is a block diagram showing a conventional example including a scramble decoder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 BS antenna 2 BS front end 2a Channel selection circuit 2b FM demodulation circuit 3 Video detection demodulation circuit 3a Input processing section 3b Detection processing section 4 QPSK, PCM demodulation circuit (audio signal output means) 5 D / A converter (audio signal output) Means) 6 Microcomputer (detection means, control means) 14 Video output terminal 15, 16 Audio output terminal 17 Detection input terminal 41-43 Return input terminal (video input terminal) 104 Satellite receiver 105 Another satellite receiver 200 Scramble Decoder SW6, SW7 switch (switching means)

Claims (1)

[Claims] 1. A front end that demodulates an input IF signal and outputs a detection signal; a video detection demodulation circuit that processes the detection signal to extract a video signal and separates an audio subcarrier signal; An audio signal output means for processing the subcarrier signal to extract an audio signal, a detection means for detecting whether or not the input IF signal is a scrambled signal, and a scramble decoder for descramble the detected signal. In the satellite broadcasting receiver provided, the audio signal output means is an audio descrambling means for descrambling the audio signal when the audio signal is taken out, and the scramble decoder is used for the video descrambling for descrambling the video signal. A scramble means, a video signal descrambled by the scramble decoder, and A video and audio output terminal for outputting the audio signal output from the audio signal output means to the outside, a detection input terminal for inputting a detection signal from the outside, and the IF signal input to one terminal The detection signal obtained from is input, the detection signal from the outside input from the detection input terminal is input to the other terminal, and these detection signals are selectively input to the video detection demodulation circuit and the scramble decoder. First switching means for supplying, and second switching in which the video signal output from the video detection demodulation circuit is input to one terminal and the video signal output from the scramble decoder is input to the other terminal. Means and control means for switching and controlling the first and second switching means according to a detection signal or a selection signal from the detection means. Satellite Receiver, characterized in that the.