JPH04358489A - Satellite broadcast receiver - Google Patents

Abstract

PURPOSE:To stop power to a video processing section and a video display section when no television video image is in existence and only additional independent audio broadcast is received. CONSTITUTION:Power is supplied to a video processing section 6 and a video display section 8 at TV viewing, and when only an additional independent audio broadcast is listened to, a recipient operates an additional independent audio changeover circuit 12 and a video display changeover circuit 13 to set an additional independent audio switching signal (f) to an H level and to set a video display switching signal (g) to an L level and the result is fed to a logic circuit 11. Then the logic circuit 11 sends a video display interrupt signal (e) of an L level to an interrupt circuit 10, which is interrupted thereby stopping power from a power supply section 9 to the video processing section 6 and the video display section 8, and the logic circuit 11 gives an additional independent audio selection signal (d) to a selector 5b, which selects sets of channels 3, 4 and the additional independent audio signal from an audio reproduction circuit 5a is fed to speakers 7a, 7b.

Description

[Detailed description of the invention]

0001 [Purpose of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite broadcasting receiver capable of receiving broadcast waves sent from a satellite and reproducing additional independent audio in the signal.

0003

[Prior Art] Test broadcasting using the practical broadcasting satellite BS-2a began in 1984, and in 1987, the world's first 24-hour satellite broadcasting using DBS (satellite broadcasting directly received at home) was carried out and became a full-fledged service. The era of satellite broadcasting has arrived. Also, regular experimental broadcasting of high-definition television using the MUSE system began in 1989, and its practical application is nearing.

FIG. 3 is a general system diagram of a conventional satellite broadcast receiver. A scrambled broadcast radio wave transmitted from a satellite is received by a parabolic antenna 1, converted to a first intermediate frequency by a converter (not shown), and then constructed of an intermediate frequency amplification block, a mixing block, an FM demodulation block, etc. The signal is supplied to tuner 2. Here, the first
The intermediate frequency signal is converted into a baseband signal, that is, a video signal to which an energy spread signal is added, and an audio subcarrier that is subjected to 4-phase DPSK (4-phase differential phase keying) and multiplexed with the video signal, and then sent to the next stage. The code is supplied to the descrambler (decryptor) 3 of

The baseband signal is descrambled by a descrambler 3, converted back to a normal baseband signal (a), and supplied to a synchronous playback section 4, an audio processing section 5, and a video processing section 6, respectively. . Then, the synchronization reproduction section 4 detects a synchronization signal from the baseband signal (a) and distributes the necessary timing to each circuit, and the audio processing section 5 outputs an audio subcarrier subjected to four-phase DPSK from the baseband signal (a). An analog audio signal (b) is reproduced by a four-phase DPSK demodulator, a PCM decoder, a DA converter, etc. (not shown), and is supplied to each speaker 7a, 7b.

[0006] The audio processing unit 5 also processes a baseband signal (a
), and based on the code, the audio mode being received, that is, distinguishing between A and B modes, TV audio and additional independent audio, or monaural and stereo, etc., is performed. The analog audio signal (b) is controlled. On the other hand, the video processing section 6 uses a de-emphasis circuit, a clamp circuit, a YC separation circuit, etc. (not shown),
From the baseband signal (a) to the video signal (c) such as a color difference signal
) is reproduced and supplied to the video display unit 8, which is, for example, a CRT monitor. Note that power is supplied to each of the circuits from a power supply section 9.

[0007] Next, an explanation will be given of an audio signal when the satellite broadcasting receiver is a high-definition receiver. The method for transmitting high-definition signals is MUSE (Multiple Sub).
-Nyquist Sampling Encod
e) It has been discussed in various fields as a method and is in the process of being officially adopted as a high-definition transmission standard. The MUSE audio transmission method converts audio signals into quasi-instantaneous companding differential PCM.
frame synchronization signal, control code, and audio data.
The data is time-division multiplexed during the vertical blanking period of the video signal as an audio data frame configured by allocating bits as shown in Figure 4, and the average transmission rate is 1.35 Mbit/s.
It is transmitted using ec.

In the audio data frame, the number of audio channels is 8 bits/channel and 4 channels (sampling frequency 32 KHz) in mode A, and 2 channels (sampling frequency 48 kHz) with 11 bits/channel in mode B. At the same time, 22 bits are allocated to each control code, and 6 bits out of the 22 bits of the control code are audio mode control codes. It is set to correspond one-to-one to a total of 27 audio modes.

Among the 27 audio modes, there are three audio modes in which television audio is not transmitted and only additional independent audio is transmitted. These audio modes are considered to be used when an additional independent audio supply company different from the video supply company continues to broadcast only additional independent audio broadcasts such as high-quality stereo music after the end of the video broadcast. However, since no video signal is being transmitted at this time, nothing is displayed on the video display section 8 and only audio can be heard. In this way, when only the additional independent audio broadcast is received, unnecessary power supply to the video processing section 6 and video display section 8 of the receiver results in a waste of energy.

0010

[Problems to be Solved by the Invention] As mentioned above, in conventional satellite broadcasting receivers, even when receiving an audio mode in which there is no television image and only additional independent audio, the image processing unit and the image display unit There was an inconvenience that electricity was supplied and energy was wasted. The present invention has been made to solve the conventional problems, and when the audio mode of only additional independent audio is received, power is not supplied to the video processing section and the video display section, and the power is not supplied to the video processing section and the video display section. The purpose of the present invention is to provide a satellite broadcasting receiver that can save on costs.

[0011] [Structure of the invention]

0012

[Means for Solving the Problems] In order to achieve the above object, the present invention receives broadcast radio waves from a satellite including A-mode and B-mode audio signals, converts them into a baseband signal, and converts the baseband signal into a baseband signal. In a satellite broadcasting receiver that reproduces predetermined video and audio from the baseband signal, a video processing unit that processes a luminance signal and a color difference signal included in the baseband signal;
a video display unit that reproduces a video based on a video signal from the video processing unit; a disconnection circuit that disconnects power supply to at least one of the video processing unit and the video display unit in response to a disconnection signal; an audio processing unit that processes the included audio signal and selects an audio mode of either television audio or additional independent audio according to a selection signal; and an audio processing unit that processes the included audio signal and selects an audio mode of either television audio or additional independent audio; control for supplying the disconnection signal to the disconnection circuit when there is no TV image and only the additional independent audio is to be played back, and supplying the selection signal for selecting the additional independent audio to the audio processing section by the input means for setting the It is equipped with means.

[0013]

[Operation] When watching TV, power is supplied to the video processing section and the video display section, but when there is no TV video and only additional independent audio is being played, a signal is supplied from the input means to the control means. Accordingly, the control means supplies a disconnection signal to the disconnection circuit to disconnect the disconnection circuit, stops power supply to at least one of the video processing section and the video display section, and supplies a selection signal to the audio processing section. to select additional independent audio.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below based on the drawings. FIG. 1 is a system diagram showing an embodiment of a satellite broadcast receiver according to the present invention. This embodiment shows a monitor-integrated high-definition receiver with a built-in BS tuner, but when a satellite broadcast radio wave is received by a parabolic antenna 1, this signal is supplied to a tuner 2 and then to a descrambler 3 at the next stage. The scramble is decoded and the MUSE baseband signal (a)
will be restored to. The baseband signal (a) is distributed and supplied to a synchronous reproduction section 4, an audio processing section 5, and a video processing section 6, respectively.

The synchronization reproduction section 4 detects a synchronization signal in the MUSE baseband signal (a) and supplies necessary timing to each block. The audio processing section 5 separates an audio signal from the MUSE baseband signal (a), reproduces an analog audio signal (b) from the signal, and supplies it to speakers 7a and 7b. At this time, the audio reproduction circuit 5a detects the audio mode control code from the control code of the audio data frame shown in FIG.
Each analog audio signal (b) is reproduced.

The audio mode control code is comprised of 6 bits within the control code of the audio data frame, as shown in FIG. 4, and has a one-to-one correspondence with 27 types of audio modes. Broadly dividing these 27 types of audio modes, A mode is a mixed audio mode of TV audio and additional independent audio (from an audio mode that uses only channel 1 to an audio mode that uses all channels 1 to 4). various combinations including modes), TV audio only audio mode (
There are three types of audio modes: channels 1 to 4 are used, channel 4 is not used depending on the audio mode), and audio mode with only additional independent audio (channel 3 and channel 4 is used, channel 3 is not used depending on the audio mode). , In mode B, there is only an audio mode for TV audio (channels 1 and 2 are used; depending on the audio mode, only channel 1 is used).

Furthermore, the audio processing unit 5 includes a selector 5b, and the selector 5b selects each speaker 7a by an additional independent audio selection signal (d) supplied from a logic circuit 11, which will be described later.
, 7b is selected as a set of channel 1 and channel 2, or as a set of channel 3 and channel 4. On the other hand, the video processing section 6
is from the MUSE baseband signal (a), for example, from the CRT
Signals necessary to drive the video display section 8, which is a monitor (
c), that is, reproduce the luminance signal, color difference signal, and vertical and horizontal synchronization signals.

The video processing section 6 and the video display section 8 are connected to a power supply section 9 that supplies power to each section of the receiver via a disconnection circuit 10, and the disconnection of the disconnection circuit 10 is performed by a logic circuit described later. Video display disconnection signal (e) supplied from 11
controlled based on As described above, the logic circuit 11 receives the additional independent audio selection signal (d) and the video display cutoff signal (
e) is supplied to the selector 5b and the disconnection circuit 10, respectively, and these output signals (d) and (e) are input from the additional independent audio switching circuit 12 and the video display switching circuit 13 to the logic circuit 11 as input signals, respectively. Based on the supplied switching signal, the logic table shown in FIG. 2 is output.

The relationship between the input and output signals of the logic circuit 11 will now be explained with reference to the logic table shown in FIG. When the additional independent audio switching signal (f) is at low level L and the video display switching signal (g) is at low level L or high level H, the additional independent audio selection signal (d) is at low level L, and the selector 5b
selects the set of channel 1 and channel 2, and the level of the video display disconnection signal (e) becomes high level H to maintain the connection of the disconnection circuit 10.

Next, when the additional independent audio switching signal (f) is set to a high level H and the video display switching signal (g) is set to a low level L, the additional independent audio selection signal (d) is set to a high level H, and the selector 5b selects the set of channels 3 and 4, and the level of the video display disconnection signal (e) becomes low level L, disconnecting the disconnection circuit 10 and disconnecting the video processing unit 6 and the video display from the power supply unit 9. The power supply to section 8 is stopped. Furthermore, an additional independent audio switching signal (f),
When both the video display switching signals (g) are set to high level H, the additional independent audio selection signal (d) becomes high level H, the selector 5b selects the set of channels 3 and 4, and the video display cutting signal ( The level of e) also becomes high level H, and the connection of the disconnection circuit 10 is maintained.

Next, the operation of the above embodiment will be explained with reference to FIGS. 1 and 2. The signal from parabolic antenna 1 is
The signal is supplied to the tuner 2, decoded by the descrambler 3 at the next stage, and restored to the MUSE baseband signal (a). The baseband signal (a) is then supplied to a synchronous playback section 4, an audio processing section 5, and a video processing section 6, respectively. Next, from the MUSE baseband signal (a), the synchronization reproduction section 4 reproduces a synchronization signal and supplies it to each circuit, and the video processing section 6 generates a video signal necessary for driving the video display section 8. Play.

On the other hand, the audio processing section 5 separates the audio signal from the MUSE baseband signal (a), reproduces the analog audio signal (b) from the signal (a), and outputs the signal to the speakers 7a and 7b.
supply to. At that time, the audio reproduction circuit 5a
An audio mode control code is detected from the baseband signal (a), and each analog audio signal (b) of channels 1 to 4 is reproduced based on the code. First, when there is no additional independent audio broadcast and the receiver watches television, the additional independent audio switching circuit 12 and the video display switching circuit 13 set the additional independent audio switching signal (f) to a low level L, while switching the video display. The signal (g) is set to a low level L or a high level H. Then, the video display cutoff signal (e) becomes high level H.
Then, the disconnection circuit 11 maintains the connection, power is supplied from the power supply section 9 to the video processing section 6 and the video display section 8, and the additional independent audio selection signal (d) becomes a low level L, and the selector 5b becomes The set of channel 1 and channel 2 is selected and the television audio signal from the audio reproduction circuit 5a is supplied to the speakers 7a and 7b.

On the other hand, when there is no television image and the receiver listens only to the additional independent audio broadcast, the additional independent audio switching circuit 1
2 and the video display switching circuit 13, the additional independent audio switching signal (f) is set to high level H, while the video display switching signal (g
) is the low level L. Then, the video display disconnection signal (e
) becomes a low level L, the disconnection circuit 11 releases the connection, power from the power supply section 9 to the video processing section 6 and the video display section 8 is stopped, and the additional independent audio selection signal (d) becomes a high level H. Therefore, the selector 5b selects the set of channels 3 and 4, and supplies the additional independent audio signal from the audio reproduction circuit 5a to the speakers 7a and 7b.

[0024] In this way, when an audio mode signal with only additional independent audio is received, a considerable amount of power can be saved by stopping unnecessary power supply to the video processing section 6 and the video display section 8. You can save money. Furthermore, when a television broadcast and an additional independent audio broadcast are being broadcast at the same time, if the receiver wants to watch the television image while listening to the additional independent audio broadcast, the additional independent audio switching signal (f) can be left at a high level H. , the video display switching signal (g) is set to high level H. Then, the video display disconnection signal (e) becomes high level H, the disconnection circuit 11 is reconnected, and power is supplied from the power supply section 9 to the video processing section 6 and the video display section 8. In addition, the present invention is based on MUSE
A satellite broadcasting receiver using the MUSE-T method, which is the same method as the
It goes without saying that the present invention can also be applied to satellite broadcast receivers having the same audio mode control code.

[0025]

[Effects of the Invention] As detailed above, according to the present invention, by adding a disconnection circuit that stops power supply via a logic circuit, when a signal is received with only additional independent audio and no TV video is transmitted. This has an excellent effect in that unnecessary power supply to the video processing section and the video display section is stopped, and power can be saved.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing an embodiment of a satellite broadcast receiver according to the present invention.

FIG. 2 is a logic table of input and output signals in the logic circuit of the satellite broadcast receiver shown in FIG. 1;

FIG. 3 is a system diagram showing a conventional satellite broadcast receiver.

FIG. 4 is an explanatory diagram showing bit allocation of an audio data frame in high-definition.

[Explanation of symbols]

5...Audio processing section, 5b...Selector, 6...Video processing section, 8...Video display section, 10... disconnection circuit, 11...logic circuit, 12...Additional independent audio switching circuit, 13...Video display switching circuit.

Claims (1)

[Claims] 1. A satellite broadcasting receiver that receives broadcast radio waves from a satellite including A-mode and B-mode audio signals, converts them into baseband signals, and reproduces predetermined video and audio from the baseband signals, comprising: a video processing unit that processes a luminance signal and a color difference signal included in the baseband signal; a video display unit that reproduces video using the video signal from the video processing unit; and at least one of the video processing unit and the video display unit. a disconnection circuit that disconnects the power supply according to a disconnection signal, and an audio that processes an audio signal included in the baseband signal and selects an audio mode of either television audio or additional independent audio according to the selection signal. A processing unit, input means for setting on/off of the video display unit, and selection of the audio mode supply the disconnection signal to the disconnection circuit when there is no television image and only additional independent audio is to be reproduced. A satellite broadcasting receiver comprising: a control means for supplying the selection signal for selecting additional independent audio to the audio processing section.