JPH05344511A - Satellite broadcasting receiving system - Google Patents

Abstract

PURPOSE:To obtain a satellite broadcasting receiving system capable of execut ing the automatic switching of a video output and a voice output, the automatic supply of AC power and the automatic switching of an FM detection output and a bit stream output even at the time of receiving high-definition broadcast ing. CONSTITUTION:A judging means for a high definition broadcasting signal based upon a broadcasting carrier level and an N-SYNC signal is included in a microcomputer 27A. On the other hand, a judging circuit 40 for judging the existence of a plug input to an AFC input terminal 39 is connected and an AND output between a high definition broadcasting judging signal and an AFC input existence judging signal is outputted as a judging signal indicating the execution of high definition broadcasting reception. When the 1st, 2nd and 3rd switching means 41, 42, 44 are properly switched by means of the judging signal, the automatic switching of a video output and a voice output, the automatic supply of AC power and the automatic switching of an FM detection output and a bit stream output to a MUSE/NTSC converter 13 connected to a BS tuner 11 are respectively executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite broadcast receiving system capable of receiving a high quality broadcast (hereinafter referred to as high definition broadcast) by connecting a MUSE / NTSC converter.

[0002]

2. Description of the Related Art Currently, satellite broadcasting in Japan is NHK.
(Japan Broadcasting Corporation) general satellite broadcasting channel 2 and JS
B (Japan Satellite Broadcasting Co., Ltd.) 1 pay channel,
A total of 4 channels are broadcast, including 1 channel for high-definition broadcasting.

FIG. 3 shows a general satellite broadcast receiving system. In Figure 3, BS tuner (high-definition compatible),
Scramble decoder for descrambling to receive pay broadcasts, and MUSE for converting MUSE signals to NTSC signals to receive high-definition broadcasts
An example of connection between a / NTSC decoder and a television receiver is shown. The BS tuner 11 inputs the BS-IF signal from the BS antenna and the converter 10, while supplying the FM detection output and the bit stream output to the scramble decoder 12. Also, BS tuner 1
No. 1 needs to supply the FM detection output to the MUSE / NTSC converter 13 while inputting an AFC pulse from the MUSE / NTSC converter 13.

In FIG. 3, the video / audio output from the BS tuner 11 is input to the AV television receiver 14 in the case of general satellite broadcasting, and the video / audio output from the scramble decoder 12 in the case of scrambled broadcasting. Input to the receiver 14. In the case of high-definition broadcasting, the video / audio output from the MUSE / NTSC decoder 13 is input to the receiver 14.

FIG. 4 shows a concrete example of the BS tuner 11. In FIG. 4, the BS antenna and converter 10
The BS-IF input from is converted into a second IF signal by the second converter 21, and then the video signal processing circuit 22
Then, processing such as FM detection is performed, and video output and FM detection output are output. A keyed AFC pulse is input from the AFC input terminal 39 to the second converter 21, and tuning data is input from the microcomputer 27. The FM detection output from the video signal processing circuit 22 is further supplied to the QPSK demodulation circuit 23, where it is QPSK demodulated and the bit stream output is output. Bitstream output is PC
M encoder 24, digital filter 25, and D /
Audio is demodulated in the portion including the A converter 26 and output as audio outputs of the left (L) and right (R) channels. The audio PCM data from the PCM encoder 24 is supplied to the microcomputer 27. The microcomputer 27 includes means for detecting a scramble discrimination signal included in the audio PCM data and discriminating the scrambled broadcast. In addition, the microcomputer 27
Shows tuning information (tuning voltage) according to key operation from the outside
Is also provided to the second converter 21 to have a function of performing tuning control.

The FM detection output from the video signal processing circuit 22 is supplied to the input terminal H of one switch 41a of the switch means 41, and the bit stream output from the QPSK demodulation circuit 23 is the other switch of the switch means 41. It is supplied to the input terminal H of 41b. The other input end L of the switch 41a is connected to the FM detection input terminal 31, and the other input end L of the switch 41b is connected to the bit stream input terminal 32. The output end of the switch 41a is connected to the FM detection output terminal 33, and the output end of the switch 41b is connected to the bitstream output terminal 34. The switches 41a and 41b are both scramble discrimination signals "H" and "H" from the microcomputer 27.
The switching is performed at the same time with L ".

The FM detection input terminal 31 and the bit stream input terminal 32 are adapted to receive the FM detection output and the bit stream output from another satellite broadcast receiving device, respectively. The outputs from the FM detection output terminal 33 and the bit stream output terminal 34 are input to the FM detection input terminal and the bit stream input terminal of the scramble decoder 12.

The video output from the video signal processing circuit 22 is supplied to the input terminal H of one switch 42a of the switch means 42, and the bit stream output from the D / A converter 26 is the other switch of the switch means 42. It is supplied to the input terminal H of 42b. The other input end L of the switch 42a is connected to the video input terminal 35, and the other input end L of the switch 42b is connected to the audio input terminal 36. The output end of the switch 42a is connected to the video output terminal 37, and the output end of the switch 42b is connected to the audio output terminal 38. Then, the switches 42a,
Both 42b are switched at the same time by the scramble discrimination signals "H" and "L" from the microcomputer 27.

The video input terminal 35 and the audio input terminal 3
The video output and the audio output from the scramble decoder 12 are input to 6 respectively. Each output from the video output terminal 37 and the audio output terminal 38 is input to each input terminal of an AV television receiver not shown.

On the other hand, the AC power supply line (referred to as AC power supply line) of the scramble decoder 12 is connected to the AC output terminal 43, and the AC power supply to the AC output terminal 43 is performed through the switch means 44. Is becoming The switch means 44 is turned on and off according to the scramble discrimination signal "H", "from the microcomputer 27.
It is performed according to L ".

A keyed AFC pulse can be input to the AFC input terminal 39 from a MUSE / NTSC converter (not shown) when receiving high-definition broadcast.

In the above structure, the scramble discrimination signal is at the "L" level during general satellite broadcast reception,
Since the switch means 41 and 42 select the L side and the BS tuner 11 does not need the scramble decoder 12, the video output terminal 37 and the audio output terminal 38 of the BS tuner 11 receive the received signal from the BS tuner side. Since it is output and the switch means 44 is off, AC power is not supplied to the external AC output terminal 43 connected to the AC power line of the scramble decoder 12. At this time, the FM detection output terminal 33 and the bit stream output terminal 34 receive an F signal input from another satellite broadcasting device.
The M detection output and the bit stream output are output.

When the BS tuner 11 receives the scrambled broadcast, the scramble discrimination signal is "H",
The switching means 41 and 42 select the H side, and the FM detection output terminal 33 and the bit stream output terminal 34 are set to B.
The FM detection output and bit stream output from the S tuner 11 side are output and supplied to the scramble decoder 12, and the switch means 44 is turned on. Therefore, the external AC output connected to the AC power supply line of the scramble decoder 12 is output. AC power is supplied to the terminal 43 to automatically turn on the power of the scramble decoder 12, and the video output terminal 37 and the audio output terminal 38 are connected to the video input terminal 3
5, the descramble output of the scramble decoder 12 input to the audio input terminal 36 is output and supplied to the AV television receiver (not shown) through the video output terminal 37 and the audio output terminal 38.

As described above, the conventional satellite broadcast receiving system operates as described above when the scramble discrimination signal included in the audio PCM data of the broadcast signal is detected and the scramble broadcast is discriminated. At times, since the high-definition detection signal is not included in the broadcast signal, automatic switching of video output and audio output, such as when connecting a scramble decoder, automatic AC power supply,
The operation of automatic switching between FM detection output and bit stream output cannot be performed.

[0015]

As described above, in the conventional satellite broadcast receiving system, the BS tuner has a MUSE.
By connecting the / NTSC converter, it was not possible to perform automatic switching of video output and audio output, automatic supply of AC power, automatic detection of FM detection output and bitstream output when receiving high-definition broadcasting.

Therefore, the present invention is to solve the above-mentioned problem, and automatically switches between video output and audio output when receiving high-definition broadcasting, and automatically supplies AC power.
It is an object of the present invention to provide a satellite broadcast receiving system capable of automatically switching between FM detection output and bit stream output.

[0017]

SUMMARY OF THE INVENTION A satellite broadcast receiving system of the present invention comprises a frequency conversion means for converting a received satellite broadcast signal into a predetermined intermediate frequency, and an FM detection output and a video output from the output of the frequency conversion means. First demodulating means for obtaining the same, second demodulating means for demodulating the FM detection output to obtain a bitstream output, a PCM encoder for converting the bitstream output into a digital audio signal, and converting the digital audio signal. , D / A conversion means for obtaining analog audio output, FM detection output and bit stream output from the first demodulation means and second demodulation means, and FM detection output and bit from other satellite broadcast receiving equipment First switch means for switching between stream output and FM detection output from the first switch means are inputted, and video output, M to obtain voice output, and the AFC output
A USE / NTSC converter, the first demodulation means,
And second switch means for switching the video output and audio output from the D / A conversion means and the video output and audio output from the MUSE / NTSC converter, and the video output from the second switch means, The MU from the television receiver to which the audio output is supplied and the AC power source.
It has a third switch means for turning on / off the power supply to the SE / NTSC converter, and a function for controlling the tuning of the frequency conversion means, and has a MUSE / NTS at the AFC input terminal.
An output that determines that there is an AFC pin plug input of the C converter, an output that determines that there is no broadcast signal other than HDTV based on the audio PCM data from the PCM encoder, and a carrier of the broadcast signal that is input to the frequency conversion means. The AGC output corresponding to the level is waveform-shaped with a predetermined threshold value, and the function to determine whether the high-definition broadcast is being received by taking the logical product with the output that is determined to be the broadcast signal is present. In the above, the first switch means is switched to FM detection output and bit stream output from the first demodulation means and the second demodulation means, and the second switch means is switched to the M switch.
The present invention is characterized by comprising control means for controlling to turn on the third switch means while switching to video output and audio output from the USE / NTSC converter.

[0018]

In the present invention, when the MUSE / NTSC converter is connected, it is possible to detect that high-definition broadcasting is being received. Therefore, as with the case where the scramble decoder is connected, the video output and the audio output are automatically output. Switching, automatic supply of AC power, automatic detection of FM detection output and bit stream output can be performed.

[0019]

EXAMPLES Examples will be described with reference to the drawings. FIG. 1 is a block diagram showing a satellite broadcast receiving system according to an embodiment of the present invention. In this figure, the same parts as those in FIG. 3 and FIG.

In FIG. 1, the BS antenna and the BS-IF input from the converter 10 are connected to the second converter 21.
After being converted into a second IF signal at, the video signal processing circuit 22 performs processing such as FM detection, and outputs video and F
The M detection output is output. Second converter 2
1, a keyed AFC pulse is input from the AFC input terminal 39, and tuning data is input from the microcomputer 27A. The second converter 21 sets the carrier level of the broadcast signal to be input. The AGC voltage corresponding to the magnitude is output. The FM detection output from the video signal processing circuit 22 is further supplied to the QPSK demodulation circuit 23, where it is QPSK demodulated and the bit stream output is output. The bitstream output is the PCM encoder 24,
Audio is demodulated in a portion including the digital filter 25 and the D / A converter 26, and output as audio outputs of the left (L) and right (R) channels. The audio PCM data from the PCM encoder 24 is sent to the microcomputer 2
Supplied to 7A. The microcomputer 27A detects the presence / absence of the N-SYNC signal included in the audio PCM data, and detects the presence / absence of the waveform-shaped output by comparing the AGC output from the second converter 21 with a certain level in the comparator 28. Or the AFC
By detecting the presence / absence of a plug input determination signal from the circuit 40 for determining the presence / absence of a pin plug input connected to the input terminal 39, or by detecting the scramble determination signal included in the audio PCM data during scramble broadcasting, A broadcast discriminating means 270 for discriminating presence / absence of high-definition broadcast or scramble broadcast is included. Also,
The microcomputer 27A receives the tuning information (tuning voltage) according to the key operation from the outside, and outputs it to the second converter 21.
It also has a function of performing tuning control.

The FM detection output from the video signal processing circuit 22 is input to the input terminal H of one switch 41a of the switch means 41, and the bit stream output from the QPSK demodulation circuit 23 is the other switch of the switch means 41. Input to the input terminal H of 41b. The other input end L of the switch 41a is connected to the FM detection input terminal 31, and the other input end L of the switch 41b is connected to the bit stream input terminal 32. The output end of the switch 41a is connected to the FM detection output terminal 33, and the output end of the switch 41b is connected to the bitstream output terminal 34.
The switches 41a and 41b are both switched at the same time by the broadcast discrimination signals "H" and "L" from the broadcast discrimination means 270 in the microcomputer 27A.

The FM detection input terminal 31 and the bit stream input terminal 32 are respectively input with the FM detection output and the bit stream output from another satellite broadcast receiving device. The outputs from the FM detection output terminal 33 and the bit stream output terminal 34 are input to the FM detection input terminal and the bit stream input terminal of the scramble decoder 12.

The video output from the video signal processing circuit 22 is supplied to the input terminal H of one switch 42a of the switch means 42, and the bit stream output from the D / A converter 26 is the other switch of the switch means 42. It is supplied to the input terminal H of 42b. The other input end L of the switch 42a is connected to the video input terminal 35, and the other input end L of the switch 42b is connected to the audio input terminal 36. The output end of the switch 42a is connected to the video output terminal 37, and the output end of the switch 42b is connected to the audio output terminal 38. Then, the switches 42a,
Both 42b are switched at the same time by the broadcast discrimination signals "H" and "L" from the broadcast discrimination means 270 in the microcomputer 27A.

The video input terminal 35 and the audio input terminal 3
The video output and the audio output from the scramble decoder 12 are input to 6 respectively. Each output from the video output terminal 37 and the audio output terminal 38 is input to each input terminal of an AV television receiver not shown.

On the other hand, the AC power supply line of the scramble decoder 12 is connected to the AC output terminal 43.
Power is supplied to the C output terminal 43 from an AC power source (not shown) through the switch means 44.
The switch means 44 is turned on and off according to "H" and "L" of the broadcast discrimination signal from the microcomputer 27A.

MUSE / is connected to the AFC input terminal 39.
A keyed AFC pulse is input from the NTSC converter 13 and supplied to the second converter 21 as an AFC input. The FM detection output from the FM detection output terminal 33 is input to the MUSE / NTSC converter 13, and an NTSC video signal and an audio signal are output as the video input terminal 35 and the audio input terminal 36, respectively.
It is supposed to be input to. The AC power supply line of the MUSE / NTSC converter 13 is connected to the AC output terminal 43, and the AC power supply to the AC output terminal 43 is performed via the switch means 44 as in the case of the scramble decoder 12. Is becoming

FIG. 2 shows the structure of the broadcast discrimination means 270. In FIG. 2, the broadcast discrimination means 270 is
3-input AND gate 271 and 2-input OR gate 27
It consists of two. AND gate 271 is AFC
Input terminal 39 has MUSE / NTSC converter 13A
An output that determines that there is an FC pin plug input (AFC
Output) "H", output "H" that is determined to be no N-SYNC signal included in audio PCM data of general broadcast and scramble broadcast, and AGC output of second converter 21 that changes according to carrier level of input broadcast signal Is input to the comparator 28, the waveform is shaped with a predetermined threshold value, and the logical product is calculated with the output "H" which is determined to be the broadcast signal. To get Of course, if one of the three inputs is "L", the AND gate 271 is at "L" level indicating that there is no high-definition broadcast. In the above determination method, although there is a carrier of a broadcast signal in high-definition broadcasting, audio PCM of general satellite broadcasting and scramble broadcasting
This is based on the fact that there is no N-SYNC signal data included in the data.

The OR gate 272 is an AND gate 271.
And the output for determining the presence / absence of scrambled broadcasting are ORed to output a broadcast discrimination signal indicating the presence / absence of high-definition broadcasting or scrambled broadcasting.

Note that, in FIG. 2, instead of the AGC carrier presence / absence determination output, the output of the noise detection circuit used for antenna level display may be input to the comparator 28 and waveform-shaped by a predetermined threshold value may be used. ..

Next, the operation of the above embodiment will be described. When receiving a general satellite broadcast, the broadcast discrimination output of FIG. 2 is at the “L” level, the switches 41 and 42 select the L side, and the BS tuner 11 inputs the scramble decoder 12 and the MUSE / NTSC converter 13. Video input terminal 3 of BS tuner 11 because it does not require input
7. Since the reception signal from the BS tuner side is output to the audio output terminal 38 and the switch 44 is off,
The external AC output terminal 43 connected to the AC power supply line of the scramble decoder 12 is not supplied with power from an AC power supply (not shown). At this time, the FM detection output and the bit stream output, which are input from another satellite broadcast receiving device, are output to the FM detection output terminal 33 and the bit stream output terminal 34.

When the BS tuner 11 receives the scrambled broadcast, the output of the discrimination circuit shown in FIG. 2 is "H", so the switches 41 and 42 select the H side,
FM detection output terminal 33, bit stream output terminal 34
The FM detection output and bit stream output from the BS tuner 11 side are output to the scramble decoder 12, and the switch 44 is turned on. Therefore, the AC power line of the scramble decoder 12 is connected to the external AC. The output terminal 43 is supplied with power from an AC power source (not shown), and as a result, the power of the scramble decoder 12 is automatically turned on. The video output terminal 37 and the audio output terminal 38 are connected to the video input terminal 35 and the audio input terminal. 36
The descramble output (video output, audio output) of the scramble decoder 12 input to the audio output terminal is output to the AV (not shown) through the video output terminal 37 and the audio output terminal 38.
Supplied to a television receiver.

Further, when the BS tuner 11 is receiving the high-definition broadcast, the output of the discrimination circuit shown in FIG. 2 is "H", so the switches 41 and 42 select the H side, and the FM detection is performed. BS tuner 1 at output terminal 33
FM detection output from the 1 side is output and MUSE / NTS
Since it is supplied to the C converter 13 and the switch 44 is turned on, A of the MUSE / NTSC converter 13
Power is supplied from an AC power supply (not shown) to the external AC output terminal 43 to which the C power supply line is connected, and M is automatically supplied.
The power of the USE / NTSC converter 13 is turned on, and the video output terminal 37 and the audio output terminal 38 have the MUSE / N input to the video input terminal 35 and the audio input terminal 36.
The NTSC output (video output, audio output) of the TSC converter 13 is output and supplied to an AV television receiver (not shown) through the video output terminal 37 and the audio output terminal 38.

Therefore, in the satellite broadcast receiving system shown in the above embodiment, the video output and the audio output are automatically switched, the AC automatic power supply, the FM detection output and the bit stream are received not only when the scrambled broadcast is received but also when the high-definition broadcast is received. The output can be automatically switched.

Moreover, since each input / output terminal, changeover switch, etc. used for receiving the high-definition broadcast can be the same as those existing in the past for performing the above-mentioned operation at the time of receiving the scrambled broadcast, the present invention is relatively inexpensive. The invention can be realized.

[0035]

As described above, according to the present invention, automatic switching between video output and audio output, automatic AC power supply, FM detection output and bit stream output can be performed even during reception of high-definition broadcasting. Is possible.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing a configuration of broadcast discrimination means in the microcomputer shown in FIG.

FIG. 3 is a scramble decoder for a BS tuner,
FIG. 3 is a block diagram showing a connection example of a MUSE / NTSC converter and a television receiver.

FIG. 4 is a block diagram showing a conventional satellite broadcast receiving system.

[Explanation of symbols]

 11 ... BS tuner 12 ... Scramble decoder 13 ... MUSE / NTSC converter 14 ... Television receiver 27A ... Microcomputer 28 ... Comparator 31 ... FM detection input terminal 32 ... Bitstream input terminal 33 ... FM detection output terminal 34 ... Bitstream output Terminal 35 ... Video input terminal 36 ... Audio input terminal 37 ... Video output terminal 38 ... Audio output terminal 39 ... AFC input terminal 40 ... Input plug presence / absence determining circuit 41 ... Switch means 42 ... Switch means 44 ... Switch means

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H04N 7/01 J 9070-5C

Claims (1)

[Claims] 1. A frequency conversion means for converting a received satellite broadcast signal into a predetermined intermediate frequency, a first demodulation means for obtaining an FM detection output and a video output from the output of the frequency conversion means, and the FM detection output. Second demodulation means for demodulating and obtaining a bit stream output; a PCM encoder for converting the bit stream output into a digital voice signal; and D / A converting means for converting the digital voice signal to obtain an analog voice output, First switch means for switching between FM detection output and bit stream output from the first demodulation means and second demodulation means and FM detection output and bit stream output from other satellite broadcast receiving equipment; , The FM detection output from the first switch means is input,
MUSE to get video output, audio output, and AFC output
/ NTSC converter, a second demodulation means, and a second for switching between the video output and audio output from the D / A conversion means and the video output and audio output from the MUSE / NTSC converter
Switch means, a television receiver to which the video output and audio output from the second switch means are supplied, and a third switch means for turning on / off the power supply from the AC power supply to the MUSE / NTSC converter. And a function of tuning the frequency conversion means to select the AFC
The output that determines that there is an AFC pin plug input of the MUSE / NTSC converter at the input terminal, the output that determines that there is no broadcast signal other than high-definition television based on the audio PCM data from the PCM encoder, and the input to the frequency conversion means. The AGC output corresponding to the carrier level of the broadcast signal is shaped by a predetermined threshold and the logical product of the output and the output determined to be the broadcast signal is obtained to determine whether the high-definition broadcast is being received. The FM signal from the first demodulating means and the second demodulating means is sent to the first switch means in response to a broadcast reception determination signal.
While switching to detection output and bit stream output and switching the second switch means to video output and audio output from the MUSE / NTSC converter, the third switch
And a control means for controlling the switch means to turn on.