JPH04196880A - Television receiver - Google Patents

Abstract

PURPOSE:To obtain a receiving device with a simple circuit constitution and good operation convenience by switch-outputting a video signal, a sound signal and a data signal from a TV broadcasting demodulating signal processing circuit and a satellite broadcasting demodulating signal processing circuit from an output terminals more than 2 systems. CONSTITUTION:The separate simultaneous station selecting receiving operations of a TV signal and a BS signal are attained by a first front end 100 and a second front end 200 and besides, the TV broadcasting signal processing circuit and the BS demodulating signal processing circuit of 2 systems are possessed respectively. Accordingly, various receiving forms such as the TV signal simultaneous receiving of the 2 systems, the BS signal simultaneous receiving of the 2 systems BS and TV signals simultaneous receiving and so on are possible, moreover, a music selecting circuit and a frequency converting circuit are shared and besides, high frequency signal input terminal connecting becomes simple by using the front end of a simple constitution to input the TV signal and the BS signal from the same terminal. Thus, the receiving device of the smaller circuit constitution with good operation convenience that the high frequency signal input terminal connection is simple and so on can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a receiving device that receives both a TV broadcast signal and a satellite broadcast signal, and outputs a video signal, an audio signal, or a data signal after signal processing. .

[Prior Art] A conventional receiving device that receives both a TV broadcast signal and a satellite broadcast signal at once is described in Japanese Patent Application No. 61-20956. However, the conventional technology does not sufficiently consider the case where two or more front ends are used for reception.

[Problems to be Solved by the Invention] The above-mentioned conventional technology does not sufficiently consider the case where two or more front ends capable of receiving both TV broadcast signals and satellite broadcast signals are used for reception. In addition to the fact that the video and audio signal processing circuit system becomes complicated and the circuit size increases, when receiving TV broadcast signals and satellite broadcast signals and redistributing the signals, the circuit connections become complicated and the usability deteriorates. there were.

An object of the present invention is to solve the above problems and to
When receiving a satellite broadcast signal using two or more front ends that can receive both signals at once, the TV broadcast signal,
To provide an easy-to-use receiving device which enables simple input and distribution/output connection of a satellite broadcasting signal cable, has a simple circuit configuration, and is easy to use.

[Means for solving the problem] The above purpose is to provide a T
Two or more systems are provided each, including a V broadcast demodulation signal processing circuit and a satellite broadcast demodulation signal processing circuit that receives and processes satellite demodulation signals, and furthermore, high-frequency reception circuits such as a channel selection circuit and a frequency conversion circuit are used to process TV broadcast signals and satellite broadcast signals. Using two or more small front ends that are shared during signal reception, the TV broadcast demodulated signal or satellite broadcast demodulated signal output from these front ends is switched and sent to the TV broadcast demodulated signal processing circuit and the satellite broadcast demodulated signal processing circuit. Enter, TV
It is possible to simultaneously receive broadcast signals and satellite broadcast signals or to receive either one of them, and output terminals for two or more systems of video signals, audio signals, or data signals from each of the TV broadcast demodulation signal processing circuit and the satellite broadcast demodulation signal processing circuit. At the same time, a common signal input terminal is provided on each front end to input TV broadcast signals and satellite broadcast signals from the same terminal, and a signal that is a mixture of TV broadcast signals and satellite broadcast signals is connected to each front end for signal distribution. This is achieved by

[Function] Uses a small front end that can receive TV broadcast signals and satellite broadcast signals from two or more units and has a shared circuit, and also has two or more separate TV broadcast demodulation signal processing circuits and satellite broadcast demodulation signal processing circuits. By switching the devices and using them, no extra circuit is required, so a receiving device capable of receiving TV broadcast signals and satellite broadcast signals with a simple and compact circuit structure can be obtained.

In addition, by providing a common signal input terminal on each front end that inputs the TV broadcast signal and satellite broadcast signal from the same terminal, and by connecting the TV broadcast signal and satellite broadcast signal to each front end after multiplexing, the signal is distributed and connected to each front end. Since TV broadcast signals and satellite broadcast signals can be easily connected using a single cable instead of using separate cables, a receiving device with good usability can be obtained.

[Example] An embodiment of the present invention will be described below with reference to FIG.

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

In the figure, 1 is the first receiving device, lO○ is the first front end, 200 is the second front end, and 9 is T
A common signal input terminal for inputting V broadcasting signals (hereinafter abbreviated as TV signals) and satellite broadcasting signals (hereinafter abbreviated as BS signals), 2 is a video signal output terminal, 2' is an audio signal output terminal, and 4 is a common signal input terminal. The video signal has 8 outputs and 2 terminals, and 4' has 2 audio signal high-power terminals, which constitute two systems of signal high-power terminals, 8 is a distributor, 50 is a demodulation signal switching circuit, and 55 is a video and audio signal switching circuit. , 30 is a first TV demodulation signal processing circuit, 35 is a second TV demodulation signal processing circuit, 40 is a first satellite broadcasting (hereinafter abbreviated as BS) demodulation signal processing circuit, and 45 is a second BS
A demodulation signal processing circuit, 7o a reception control circuit, 80 a tuning keyboard, the first front end 100 has an input terminal 120, a branching circuit 101, a VHF-TVV signal high frequency amplification circuit 102,
U) (F-TVV high frequency amplification circuit 103, BS signal high frequency amplification circuit 104, high frequency signal switching circuit 105
, frequency conversion circuit 106, oscillation signal switching circuit 107
, V) IF-TVV variable oscillation circuit 108, UHF
- TVV variable oscillation circuit 109, BS signal variable oscillation circuit 110, TVV inter-frequency signal band filter (BP
F) 112, BS intermediate frequency signal bandpass filter (B P
F) 111, PLL channel selection circuit 113, satellite broadcast signal demodulation circuit 114, TVV transmission signal demodulation circuit 115, BS demodulation signal output terminal 121, TVV modulation signal output terminal 122, channel selection control signal input terminal 123, and The second front end 200 includes an input terminal 22o, a branching circuit 201, and a VHF-TVV high frequency amplification circuit 20.
2. UHF-TVV high frequency amplification circuit 203, BS signal high frequency amplification circuit 204, high frequency signal switching circuit 20
5. Frequency conversion circuit 206, oscillation signal switching circuit 20
7, V) IF-TVV variable oscillation circuit 208, UH
F-TVV variable oscillation circuit 209, BS signal variable oscillation circuit 210, TVV inter-frequency (hereinafter abbreviated as TV/IF) signal bandpass filter (BPF) 212, BS intermediate frequency (hereinafter abbreviated as BS/IF). ) Signal bandpass filter (
BPF) 211, PLL channel selection circuit 213, satellite broadcast signal demodulation circuit 214, TVV transmission signal demodulation circuit 215, BS demodulation signal output terminal 221, TV demodulation signal direction terminal 222
The 30 first TV demodulation signal processing circuits include TVV image signal processing circuits 31 . The second TVV modulation signal processing circuit 35 has the same circuit configuration as the first TV demodulation signal processing circuit, and the first BS broadcast demodulation signal processing circuit 40 has the same circuit configuration as the first TV demodulation signal processing circuit. Video signal processing circuit 4
1. The second BS
The demodulated signal processing circuit 45 has the same circuit configuration as the first TV demodulated signal processing circuit.

The operation of the receiving device shown in FIG. 1 will be explained.

The satellite broadcast signal of 11 to 12 GHz is converted to the first intermediate frequency band of satellite broadcast of approximately 1 to 2 GHz by a down converter (not shown), mixed with the TV broadcast signal, and input to the common signal input terminal 9. . The signal is re-inputted by the distributor 8 into the input terminal 120 of the first front end 100 and the input terminal 220 of the second front end 200.

In the first front end 100, the VH
The signal is split into three frequency bands: F-TV signal, UHF-TV signal, and BS signal. After being amplified by one of the high-frequency amplifier circuits 102 to 104 according to the receiving channel, the signal is selected by the high-frequency signal switching circuit 105. , frequency conversion circuit 1
Variable oscillation circuit control circuit 10 according to the receiving frequency band at 06
One of the oscillation signals from 8 to 110 is selected and inputted to the oscillation signal switching circuit 107, and the frequency of the TV/IF multiplied signal or the BS/IF multiplied signal is converted. After that, TV/IFB
After band selection by the PFl 12 or the BS-IFBPFI 11, the signals are input to the respective satellite broadcast signal demodulation circuits 114 and TV broadcast signal demodulation circuits 115 for demodulation. The satellite broadcasting signal is a video, audio, and data signal that is FM-modulated all at once, and the satellite broadcasting signal demodulation circuit 114 performs FM demodulation and sends the demodulated baseband signal to the BSS demodulated signal power terminal 121. Output. In addition, since the TV broadcast signal is transmitted as a video signal and data signal as an AM modulated signal, and as an audio signal as an FM modulated signal, the TV broadcast signal demodulation circuit 1
15 performs a video signal AM demodulation operation and an audio signal FM demodulation operation, and outputs a baseband signal which is a video demodulation signal and an audio demodulation signal from the TV demodulation signal output terminal 122. Tuning is performed by inputting a tuning control signal corresponding to the tuning signal from the tuning keyboard 80 from the reception control circuit 70 to the PLL tuning circuit 113 via the tuning control signal input terminal 123, At the same time, the oscillation frequency is controlled according to the selected channel, and an intermediate frequency signal of the desired channel is output to perform the channel selection operation. At this time, the high frequency amplification circuits l○2 to 104 perform selective amplification operations according to the frequency band of the desired channel, signal selection occurs in the high frequency signal switching circuit 105, and oscillation signal switching circuit 1
07 Oscillation signal selection, satellite broadcasting signal demodulation circuit 114 and TV
Operation control of the broadcast signal demodulation circuit 115 (when one demodulation circuit is in operation, the other stops its operation) is simultaneously performed by a channel selection control signal (not shown). The second front end 2o○ also performs a similar channel selection operation.

Further, in the first TV broadcast signal processing circuit 30, the TV demodulated signal is subjected to video signal processing such as amplitude adjustment and audio signal carrier removal in the TV video signal processing circuit 31.
The TV audio signal processing circuit 32 performs stereo demodulation of the audio multiplexed signal and outputs the TV video and audio signals to the audio and video signal switching circuit 55 . Similarly, the second TV broadcast signal processing circuit 35 outputs TV audio and video signals to the audio and video signal switching circuit 55. On the other hand, in the BS demodulation signal processing circuit 40, the BS video signal processing circuit 41 performs video signal processing such as energy diffusion signal removal, FM modulation signal de-emphasis, synchronization signal regeneration, and amplitude amplification on the BS demodulation signal. , BS audio signal processing circuit 4
2, the audio digital signal in the frequency band from the BS demodulated signal is sampled and subjected to QPSK (Quadrature Phase Shift Key) demodulation, and then the QPSK demodulated digital signal is subjected to PCM (Pulse Code Modulation) decoding. At the same time, it is converted into an analog audio signal. The signal-processed BS audio and video signals are output to the video and audio signal switching circuit 55. Similarly, the second BS broadcast signal processing circuit 45 outputs BS audio and video signals to the audio and video signal switching circuit 55. They are output from the output terminals 6, respectively. The audio/video signal switching circuit 55 switches and selects the input BS audio/video signal or TV audio/video signal, and outputs the video signal from terminal 1 and audio signal! It outputs from two output terminals: an output terminal 2', a video signal output 2 terminal 4, and an audio signal output 2 terminal 4'.

As explained above, according to the present embodiment, the first front end 100 and the second front end 200 can perform separate and simultaneous reception operations for TV signals and BS signals, and each Since it has a TV broadcast signal processing circuit and a BS demodulation signal processing circuit, it can (1) simultaneously receive two systems of TV signals, (2) simultaneously receive two systems of BS signals, (3) simultaneously receive BS and TV signals, etc. A variety of reception formats are possible, and by using a front end with a simple configuration that shares the channel selection circuit and frequency conversion circuit, and inputs the TV signal and BS signal from the same terminal, it is possible to connect the high frequency signal input terminal. It is possible to obtain a receiving device with a compact circuit configuration that is easy to use and easy to use.

FIG. 2 is a block diagram showing a second embodiment of the invention. In the figure, 10 is a second receiving device, 300 is a third front end, 51 is a demodulated signal switching circuit, 56 is a video and audio signal switching circuit, and 300 is a third front end.
00 is input terminal 320, branching circuit 301, VHF
-TVfi No.i%t[ii1 width circuit 302,t,”HF
-TV signal high frequency amplification circuit 303, high frequency signal switching circuit 305, frequency conversion circuit 306, oscillation signal switching circuit 307, VHF -TV signal variable oscillation circuit 30
8. UHF/TV signal variable oscillation circuit 309, TV intermediate frequency signal bandpass filter (BPF) 312, PLL channel selection circuit 313, TV broadcast signal demodulation circuit 315, TV demodulation signal output terminal 322, channel selection control signal input The terminal 323 is comprised of terminals 323, and in the figure, the same numbers as those in FIG. 1 are given to those that perform the same operations as those in FIG. 1, and explanations thereof will be omitted.

The operation of the second receiving device 10 shown in FIG. 2 will be explained. Compared to the first front end 100, the third front end 300 does not have a BS signal reception function and can only receive TV signals, and the other operations are the same. The demodulated signal switching circuit 51 is connected to the T of the first front end 100
V demodulation signal output terminal 122 and third front end 3
Only the TV demodulated signal from the TV demodulated signal output terminal 322 of 00 is switched and inputted to the first TV demodulated signal processing circuit 30 and the second TV demodulated signal processing circuit 35. Further, the BS demodulated signal from the BS demodulated signal output terminal 121 of the first front end lOO is directly connected to the first BS demodulated signal processing circuit 40 without passing through a switching circuit. The video and audio signal switching circuit 56 inputs one system of BS video and audio signals and two systems of TV video and audio signals, switches and selects them, and outputs them to the video signal output terminal 1 terminal 2, the audio signal output terminal 2', and the video signal output terminal 2'. Signal output 2 terminal 4 and audio signal output 2
It outputs from the two output terminals of terminal 4'.

As explained above, according to this embodiment, it is possible to (1) simultaneously receive two systems of TV signals, (2) simultaneously receive BS and TV signals, and also share the channel selection circuit, frequency conversion circuit, etc. Moreover, by using a front end with a simple configuration that inputs a TV signal and a BS signal from the same terminal, the connection of the high frequency signal input terminal is simplified, and a receiving device with a compact circuit configuration that is easy to use can be obtained. Furthermore, by using only one system of BS demodulation signal processing circuits, which are expensive and complicated circuits, the receiving function is slightly inferior compared to the embodiment of the present invention shown in FIG. A receiving device capable of simultaneously receiving BS signals can be obtained.

FIG. 3 is a block diagram showing a third embodiment of the present invention. In the figure, 20 is a third receiving device, 21 is a distribution signal 8-output terminal, 22 is a distributor, 23 is a combining circuit, 24 is an isolator circuit, 25 is an amplifier circuit, 27 is a distribution circuit,
85 is a high frequency modulation signal output switching circuit, 86 is a high frequency modulation circuit, 87 is a video signal input terminal for modulation, and 88 is an audio signal input terminal for modulation. In the figure, parts that perform operations similar to those in FIG. 1 are given the same numbers as those in FIG. 1, and explanations thereof will be omitted.

The operation of the third receiving device 30 shown in FIG. 3 will be explained. The receiving operation is similar to that of the receiving apparatus shown in FIG. 1, but in this embodiment, a high frequency modulation signal, an external TV signal, and a BS signal are mixed and output. The modulated signal from the video signal input terminal 87 for modulation and the audio signal input terminal 88 is
Reference numeral 6 denotes a high frequency modulation circuit which performs high frequency modulation similar to a broadcast signal to a specific channel, and outputs a high frequency modulation signal from an 8 power switching circuit 8 and a channel selection control circuit 70 in accordance with a control signal.

The distributor 22 divides the TV signal and BS signal from the common input terminal 9 into three parts using a distribution circuit 27, and distributes the TV signal and BS signal from the common input terminal 9 into three parts.
00 input terminal 120 and second front end 200
After being amplified by the amplifier circuit 23, the signal is input to the synthesis circuit 25 via the isolator circuit 24. The synthesis circuit 25 mixes the signal with the high frequency modulation signal from the high frequency modulation signal output switching circuit 85 and outputs the mixed signal.

As explained above, according to this embodiment, the configuration is simple by using a front end with a simple configuration that shares the channel selection circuit, frequency conversion circuit, etc., and inputs the TV signal and BS signal from the same terminal. (1) Simultaneous reception of 2 systems of TV signals, (2) Simultaneous reception of 2 systems of BS signals, (3) B
In addition to various reception formats such as simultaneous reception of S and TV signals, it also has a function that mixes and outputs high frequency modulation signals, etc. Even when there is input/output of these multiple signals, BS and TV signals are combined into one signal system. Since it can be treated as a wire and connected, it is easy to connect the high-frequency signal input terminal, and it is possible to obtain an easy-to-use receiving device with a compact circuit configuration. It goes without saying that similar effects can be obtained by using the distributor 22 of this embodiment in combination with the receiving apparatus of the present invention shown in FIG.

FIG. 4 is a block diagram showing a fourth embodiment of the present invention. In the same figure, 90 is a BS signal input terminal, 91 is a T
A V signal input terminal, 96 a mixing circuit, and 97 a BS power supply circuit.

In the same figure, the BS signal and the TV signal are input through separate signal lines, and after being mixed in the mixing circuit 96, the signal is passed through the distributor 8 to the first
and is connected to the input terminal of the front end of the receiving device of the present invention shown in the second section.

The BS power supply circuit 97 is for supplying power supply voltage to the down converter 90 connected to the BS signal input terminal, and the mixing circuit 96 is configured to supply power only to the BS signal input terminal 90.

In this embodiment, even if the signals are transmitted through separate signal lines, the signal connection is made by mixing the BS signal and the TV signal, and the high-frequency signal input terminal connection is simplified, making it easy to use and compact. A receiving device having a circuit configuration is obtained. In addition,
Similar effects can be obtained even when used in combination with the embodiments of the present invention shown in FIGS. 2 and 3.

In the first, second, third, and fourth embodiments of the present invention described above, two front ends capable of receiving BS signals and TV signals are connected and used, but more front ends are connected. The same effect can also be obtained even if two or more systems of demodulated signal processing circuits are provided and two or more sets of switching signals are output.

Further, in the embodiments of the present invention, the demodulation and signal output of data signals are not described in detail, and it goes without saying that data signal output of multiple systems is possible even in these embodiments.

[Effects of the Invention] According to the present invention, in a receiving device that receives a TV signal and a BS signal and switches and outputs two or more sets of video and audio signals, a channel selection circuit, a frequency conversion circuit, etc. are shared, and a TV demodulated signal and a TV demodulated signal can be combined. Using multiple front ends with a simple configuration that outputs the BS demodulated signal and inputs the TV signal and BS signal from the same terminal, the demodulated signal from the front end is switched and input to two or more demodulated signal processing circuits, and the signal is output. By doing so, (1) simultaneous reception of two TV signal systems, (2)
A front end with a simple configuration that is capable of various simultaneous channel selection reception operations such as simultaneous reception of two systems of BS signals and (3) simultaneous reception of BS and TV signals, and also inputs TV signals and BS signals from the same terminal. By using this, it is possible to obtain a receiving device with a smaller circuit configuration, which is easier to use, such as by simplifying the connection of the high frequency signal input terminal.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of the present invention;
FIG. 3 is a block diagram showing a second embodiment of the invention, FIG. 3 is a block diagram showing a third embodiment of the invention, and FIG. 4 is a block diagram showing a fourth embodiment of the invention. .

Claims (1)

[Scope of Claims] 1. Two front ends are provided to which TV broadcast signals and satellite broadcast signals are input, and at least a channel selection circuit is also shared when receiving TV broadcast signals and satellite broadcast signals, The front end is equipped with a TV broadcast demodulation circuit and a satellite broadcast demodulation circuit that receive a TV broadcast signal and a satellite broadcast signal, respectively, and output a TV broadcast demodulated signal or a satellite broadcast demodulated signal after channel selection. The demodulated signal is switched and inputted to at least two or more systems of TV broadcast demodulation signal processing circuits and satellite broadcast demodulation signal processing circuits, thereby making it possible to simultaneously receive the TV broadcast signal and the satellite broadcast signal, or to receive either one of the TV broadcast signal and the satellite broadcast signal. A receiving device characterized in that video signals, audio signals, or data signals from the TV broadcast demodulation signal processing circuit and the satellite broadcast demodulation signal processing circuit are switched and outputted from two or more output terminals. 2. A first device into which a TV broadcast signal and a satellite broadcast signal are input, which shares at least a channel selection circuit when receiving the TV broadcast signal and the satellite broadcast signal, and is equipped with a TV broadcast demodulation circuit and a satellite broadcast demodulation circuit for demodulating the signal. front end and TV
T that receives broadcast signals and performs channel selection and signal demodulation
a second front end equipped with a V broadcast demodulation circuit; a two-system TV broadcast demodulation signal processing circuit for receiving and signal-processing the TV broadcast demodulation signals from the first and second front ends; It consists of a satellite broadcast demodulation signal processing circuit that receives and processes the satellite broadcast demodulation signal from the front end of the TV.
A receiving device characterized in that a video signal and an audio signal or a data signal from a broadcast demodulation signal processing circuit and a satellite broadcast demodulation signal processing circuit are switched and outputted from two output terminals. 3. The front end according to claim 1 or the first front end according to claim 2 has a common input terminal that receives a TV broadcast signal,
A receiving device characterized in that it is configured to receive a satellite broadcasting signal. 4. The front end according to claim 1 or the first front end according to claim 2 includes a frequency conversion circuit that converts the frequency of a received signal using an oscillation signal, and at least T
A receiving device characterized in that it is used in common when receiving a V broadcast signal and a satellite broadcast signal. 5. In the receiving device according to claims 1, 2, and 3, at least a cable common signal input terminal for inputting a TV broadcast signal and a satellite broadcast signal via the same cable, and a common input terminal of the front end. A distributor comprising a plurality of distribution output terminals for distributing and outputting signals, a modulation signal input terminal from a high frequency modulation circuit, and a distribution output terminal for combining and outputting a TV broadcast signal, a satellite broadcast signal, and a modulation signal. A receiving device characterized in that it is provided between a common input terminal of a front end and a cable signal input terminal through which TV broadcast signals and satellite broadcast signals are transmitted. 6. The receiving device according to claims 1, 2, and 3, comprising two signal input terminals into which TV broadcast signals and satellite broadcast signals are input via different cables, and a common input terminal of the front end. A distributor consisting of a plurality of distribution output terminals for distributing and outputting signals, a modulation signal input terminal from a separately provided high-frequency modulation circuit, and a distribution output terminal for combining and outputting a TV broadcast signal, a satellite broadcast signal, and a modulation signal. is provided between a common input terminal of the front end and a cable signal input terminal to which TV broadcast signals and satellite broadcast signals are transmitted.