CN1047179A - The transmitting converter of pay TV and receiving transducer and transform method thereof - Google Patents
The transmitting converter of pay TV and receiving transducer and transform method thereof Download PDFInfo
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- CN1047179A CN1047179A CN 90101293 CN90101293A CN1047179A CN 1047179 A CN1047179 A CN 1047179A CN 90101293 CN90101293 CN 90101293 CN 90101293 A CN90101293 A CN 90101293A CN 1047179 A CN1047179 A CN 1047179A
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- signal
- paraphase
- circuit
- video signal
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Abstract
A kind of transmitting converter of pay TV, receiving transducer and transform method thereof, launch thereby carry out paraphase, and when receiving, the image video signal of the relevant row of the paraphase that receives is carried out paraphase again and reduce by the image video signal that makes relevant row selectively.The relative synchronous signal does not then carry out paraphase.
Description
The present invention relates to TV, the transmitting converter and receiving transducer and the transform method thereof that relate to a kind of pay TV particularly, relate in particular to selectively image video signal with relevant row and carry out the transmitting converter and the method thereof of launching after the paraphase, and the image video signal of the relevant row after the above-mentioned paraphase that receives carried out paraphase again, thereby the receiving transducer and the method thereof of reduction.
Existing pay TV comes transmitting television signals by signal cable when wire transmission, thereby the expense of laying signal cable is like this invested the very big charge raising that makes.And need during with the wireless transmission TV signal carry out encryption with " transmitting converter " to the TV signal of emission at transmitting station, general television receiver can't normally be watched, have only to mix at customer-side and could normally watch after " receiving transducer " is decrypted when conventional television set.But existing encryption, decryption method and install often more complicated, and be difficult to promote.
In order to overcome above-mentioned defective, the object of the present invention is to provide a kind of method simple and easy, be convenient to promote, and cost of investment is low, the emission of the cheap TV signal that has reasonable fee, receiving conversion devices and methods therefor.
The transmitting converter of pay TV provided by the present invention, comprise the sync separator 3 that separates the synchronizing signal in the composite video signal, the switching pulse of handling from the isolated line synchronizing signal of sync separator is formed device, produce the visual paraphase control signal generator of visual paraphase control signal according to the line synchronizing signal of separating from sync separator and frame synchronizing signal, carry out the logical circuit of logical process according to the output of switching pulse formation device and visual paraphase control signal generator, the reversing phase switch 6 that selectively image video signal of relevant row is carried out paraphase according to the output of composite video signal and logical circuit is so that do encryption to the TV signal of emission.
The emission transform method of pay TV provided by the invention is to make selectively the image video signal of relevant row to carry out launching after the paraphase.
The receiving transducer of pay TV provided by the present invention comprises high-frequency tuner, the combinational circuit that contains intermediate frequency amplifier circuit, detecting circuit, video amplifier circuit, sound accompaniment and synchronous pulse extracting circuit, the contrary treatment circuit of video that the image video signal of the relevant row after the paraphase is carried out paraphase again.
Another embodiment as receiving transducer also comprises and will reach the modulation circuit again 64 that the TV signal of high frequency is synthesized and be modulated to the audio signal of extracting from the combinations thereof circuit through the signal after the contrary processing circuit processes of video.
The image video signal of the paraphase in advance in the TV signal that the receiving conversion method of pay TV provided by the invention is to receive carries out paraphase again and recovers former normal image.
The method that the invention has the advantages that is simple and easy be convenient to promote and cost of investment low, thereby it is cheap to have reasonable fee.
Below in conjunction with accompanying drawing most preferred embodiment of the present invention is elaborated.Wherein:
Fig. 1 is transmission of television partly the simple block schematic diagram relevant with transmitting converter of the present invention;
Fig. 2 is the block schematic diagram of transmitting converter of the present invention;
Fig. 3 is the exemplary waveforms figure of the vision signal before and after the paraphase;
Fig. 4 is television reception partly the schematic diagram relevant with receiving transducer of the present invention;
Fig. 5 is the block schematic diagram of receiving transducer of the present invention;
Fig. 6 is the block schematic diagram of an embodiment of receiving transducer of the present invention;
Fig. 7 is the schematic circuit of the contrary treatment circuit of vision signal among Fig. 6 embodiment;
Fig. 8 is the oscillogram of the relevant waveform in the presentation graphs 7.
Referring to Fig. 1, Fig. 2, Fig. 3.Wherein Fig. 1 is transmission of television partly the simple block schematic diagram relevant with transmitting converter of the present invention, and Fig. 2 is the block schematic diagram of transmitting converter of the present invention, and Fig. 3 is the exemplary waveforms figure of the vision signal before and after the paraphase.1 is transmitting converter in Fig. 1, the composite video signal that gamma camera or video tape recorder etc. produced in the television transmitting station makes image video signal paraphase in the selected relevant row in the composite video signal through transmitting converter 1, thereby encrypt, and in transmitter 2, modulate high-frequency oscillation signal after transmitting antenna 3 is launched to the space with the vision signal after the conversion.Composite video signal is divided into two-way in Fig. 2, one the tunnel isolates line synchronizing signal and frame synchronizing signal through sync separator 3, wherein isolated line synchronizing signal one tunnel send switching pulse to form device 4, one the tunnel send visual paraphase control signal generator 5, and isolated frame synchronizing signal is delivered to visual paraphase control signal generator 5.In switching pulse formation device 4, will output to logical circuit 7 behind the line synchronizing signal broadening (but broadening capable square wave) for coinciding along back edge thereafter with horizontal blanking impulse, in visual paraphase control signal generator 5, produce with a frame in the previously selected corresponding square wave of time cycle that will carry out the relevant row (1 capable or continuous multirow) of paraphase, be sent to logical circuit 7, another road of composite video signal leads to reversing phase switch 6, in logical circuit 7, carry out logical process according to the visual paraphase control signal of input and the capable square wave of switching pulse formation device 4 generations, produce control signal and be sent to reversing phase switch 6, make (comprising burst signal) the then not paraphase such as line synchronizing signal in this row of image video signal paraphase in the previously selected row in reversing phase switch 6, the TV signal after will handling is then delivered to transmitter 2.Sync separator 3 among Fig. 2 can be used the circuit identical with the relevant circuit of television set, and switching pulse forms device 4, visual paraphase control signal generator 5, logical circuit 7, available with the following identical circuit of receiving transducer such as reversing phase switch 6.Fig. 3 (a) is the oscillogram of vision signal before the paraphase, and Fig. 3 (b) is the oscillogram of the vision signal after the paraphase.As can be seen from the figure 52 are horizontal synchronizing pulse, 50 is image video signal, 51 is burst signal, in Fig. 3 (b) 1,2,6, image video signal in 7 row does not have paraphase, and 3,4, image video signal in 5 row then is the previously selected signal of wanting paraphase, but the then not paraphase of line synchronizing signal in the selected row.This is to guarantee by logical circuit with by the signal that switching pulse forms device 4 output.The previously selected relevant row of wanting paraphase can be by having a coila conversion in the visual paraphase control signal generator 5, or change by switch.
Referring to Fig. 4,8 is reception antenna among the figure, and 9 is receiving transducer, and 10 is television set.Be that receiving transducer 9 is serially connected between antenna 8 and the television set 10, the image video signal of the paraphase in the resultant wherein previously selected row after frequency conversion, amplification, detection that will receive from reception antenna 8 in receiving transducer 9 recovers normal signal by paraphase once more, i.e. deciphering.
Referring to Fig. 5, Fig. 6, Fig. 7, Fig. 8,8 is reception antenna among the figure, high-frequency tuner 11 is by high-frequency amplifier 15, frequency mixer 16, local oscillator 17 is formed, and on local oscillator, be added with automatic frequency control signal AFC, this high-frequency tuner 11 may be tuned on the predetermined channel, its circuit is identical with relevant circuit in the general color television set, circuit 12 is by presetting intermediate frequency amplifier 18, during containing, Surface Acoustic Wave Filter 19 and circuit 20(put, video detection, sound accompaniment and synchronous pulse extracting circuit), circuit 12 also can be identical with the relevant circuit in the general color television set, for example, Surface Acoustic Wave Filter 19 can be used SAW2043, and circuit 20 can be used integrated package TDA4501, exportable frame excitation output signal on its " 3 " end of circuit routinely, its " 27 " end exportable SAND output signal (being the stack of line synchronizing signal and horizontal blanking signal), its " 13 " end links to each other with sound accompaniment frequency modulation output, its " 17 " end links to each other with video output terminals, its " 26 " end output row energization output signal, this external circuit 20 is also from " the AFC signal of local oscillator 17 is sent in 18 ' end output; the height that is sent to high-frequency amplifier 15 from the output of " 5 " end is put the AGC signal, sends time-delay AGC signal from " 1 " end.
One most preferred embodiment of the contrary treatment circuit 13 of video comprises capable squarer 22, frame squarer 21, counter 23, logical circuit 24, forward and reverse amplifier 26, clamp circuit 25, the first gate-controlled switches 27, the second gate-controlled switches 28, adder 29.The work of the frequently contrary treatment circuit 13 of photopic vision in conjunction with a certain encrypted form now.Be located at 32H-64H in the transmitter as an example, image video signal among the 96H-128H carries out paraphase, the signal of all lock-out pulses is then kept former state and not paraphase, row energization signal " 26 " end in circuit 20 is added on capable squarer 22 and the frame squarer 21 in the contrary treatment circuit 13 of video for this reason, row squarer 22 is monostable trigger-action circuits, the pumping signal of being expert at triggers the capable square wave (Fig. 8 1.) that the back produces a wider width, the width of its width and horizontal blanking impulse is identical and be sent to logical circuit 24, it is used for guaranteeing by making the picture intelligence of paraphase that receives again during paraphase, synchronizing signal can be by paraphase, the row energization output signal (see figure 6) that 23 pairs in counter is sent here also can be counted the capable square wave (see figure 7) of row squarer 22 outputs, and the work of counter 23 is subjected to the control of the output of frame squarer 21 again.Producing a losing side ripple (seeing that Fig. 8 3.) when frame squarer 21 is subjected to the triggering of frame pumping signal (Fig. 8 2.) is added to and makes its counting on the counter 23, counter 23 can carry out binary counting, the pulse period of its output can be 2H, 4H, 8H, 16H, 32H, 64H etc. (from different joints or by switch S 1 conversion), one example of output waveform (from Q6 output) as Fig. 8 4. shown in, the 64H in its cycle.The back edge of the square wave that frame squarer 21 is taken place is controlled by a count signal output such as the Q8 in the counter, counter 23 can be used MC/4040 type integrated package 32, its counting is imported from row energization signal or row square-wave signal with CP, the frame square wave that frame squarer 21 produces is added to the R end of integrated package 32, terminal count output Q
1-Q
4Etc. the duty ratio of exportable different cycles is 1 square wave, in the present embodiment from Q
6End is exported, and is sent to logical circuit 24, and its Q
8The signal of output then is used to control the back edge of above-mentioned frame square wave, thereby the cycle of frame square wave is 256H.Row square-wave generator 22 and frame square-wave generator 21 can share an integrated package 31, its model is MC/4013, its R1 end links to each other with the frame excitation output signal, its S1 end links to each other with the Q8 end of integrated package 32, its output Q1 links to each other with the R end of integrated package 32, the other end of integrated package 31 then is connected into monostable trigger-action circuit, thereby be connected to NOR gate G1 and R42, R43, C45 etc., the row energization output signal is held through the CP2 that the RC circuit is added to (being made up of C26, R41) integrated package 31, thereby from its Q2 end output delegation square wave, one the tunnel is sent to the CP end of integrated package 32, and one the tunnel then is sent to logical circuit 24.Logical circuit 24 is made up of NOR gate G2, NOR gate G3, NOR gate G4 in the present embodiment, G2, G4 connect into not gate, the door G2 output waveform as Fig. 8 5. shown in, be sent to the end of NOR gate G3, the capable square-wave signal of the broadening that Q2 exported of integrated package 31 as the waveform of Fig. 8 1. shown in, be added to the other end of NOR gate G3, the signal of the output of NOR gate G3 is delivered to first gate-controlled switch 27, its waveform as Fig. 8 6. shown in, the signal of exporting after the NAND gate G4 paraphase of this signal through connecting into not gate is sent to second controllable switch 28, its waveform as Fig. 8 7. shown in.First gate-controlled switch 27 is made up of the switch in the multicircuit switch integrated package 33 331, and 28 of second gate-controlled switches are made up of the switch in the multicircuit switch integrated package 33 332.Forward and reverse amplifying circuit 26 is by transistor T
1, T
3, T
4Constitute transistor T
1Be emitter follower, input has video output signals (contain synchronizing signal and picture intelligence, visible Fig. 8 8.) on its base stage, like this at transistor T
3Collector electrode on defeated and crystal T
1180 ° of base signal phase phasic differences amplification reverse signal, and at transistor T
4Collector electrode on then output and transistor T
1The forward amplifying signal of base signal homophase, adjust potentiometer W6 and can make transistor T
3, T
4The amplitude of the forward and reverse amplifying signal on two collector electrodes equates, transistor T
2Be clamper tube, its base voltage is negative 6 volts when initial, only when being added with SAND on its base stage and being the square transistor T that makes during the horizontal synchronizing pulse
2Work, thus play clamping action to picture intelligence.Transistor T
3Collector electrode on reverse amplifying signal see that through its signal waveform of switch 331(Fig. 8 9.) to be passed to adder 29(be transistor T
5), only as NOR gate G
3 Output signal switch 331 side's conductings when being " 1 ", and switch 331 not conductings when it is zero.Transistor T
4Collector electrode on the forward amplifying signal then be passed to its signal waveform of adder 29(and see Fig. 8 10. through switch 332, when the switch 332 conductings 332 not conductings of switch when it is zero during for " 1 " of the output signal of door G4.At transistor T
5Emitter on output signal (its waveform is seen Fig. 8 (11)) after the addition is arranged, the i.e. signal that ought receive (0-32H for example, during the 64H-96H etc.) during for normal signal because only switch 332 conductings, switch 331 then not conductings, thereby the signal of adder 29 output is the amplifying signal with normal signal homophase.At for example 33H-64H, during the 96H-128H etc. owing in television transmitter, image video signal has been done the paraphase processing, then not paraphase of lock-out pulse, so the time, be expert at during the square wave, switch 332 conductings, make the not paraphase of horizontal pulse of adder 29 outputs, and during image video signal, switch 331 conductings, thereby the image video signal of adder 29 output is the signal through paraphase, thereby the image video signal of encrypting recovered normal and can be input to the relevant video amplifier circuit of television receiver.The signal of adder 29 output can also with after the sound accompaniment frequency modulation output of circuit 20 mixes, be modulated into the antenna jack that a certain high frequency is delivered to domestic television set again modulation circuit 30 again.Modulation circuit can be used integrated package MC1374 again.This is a custom circuit.Then coexist mutually as for burst signal and not do paraphase in the television transmitter and handle, so in the present embodiment owing to do not do the paraphase processing in the scope of the square wave of also being expert at line synchronizing signal.Therefore the present invention not only can be used for black and white television set but also is applicable to color television set.Owing to be provided with again modulation circuit 30 and can the television set internal structure do not made any changes, and only be transformed to high-frequency TV signal after normal from the antenna end input of television set.
In television transmitter (referring to Fig. 2), described reversing phase switch 6 can be used transistor T 1, T3, T4, T5, switch 331 among Fig. 7,332 circuit, paraphase identifier 5 can be used the relevant circuit of integrated package 32 among Fig. 7, switching pulse forms device 4, the relevant circuit of integrated package 31 among available Fig. 7, logical circuit 7 can be with the relevant circuit of door G2, G3, G4 among Fig. 7, and synchronizing separator circuit 3 can be with conventional row synchronously and the split circuit of frame synchronization.Change the out splice going splice of integrated package 32 like this, promptly get the signal among the Q1-Q9 respectively, the signal that is added to the S1 end of integrated package 31 also can be taken from each counting output, and the number of times encrypted in a frame and the period of change of encryption are all correspondingly changed.There is coila corresponding as long as be contained in relative assembly and the receiving system of the present invention that links to each other with television receiver in the television transmitter.Obviously also can choose out the relevant row in the frame wantonly, wherein image video signal is carried out paraphase, the work of this image control signal paired those skilled in the art be easy to accomplish.In addition, obviously can also without the high frequency amplifier section, only directly in receiver, install the contrary treatment circuit of relevant video additional and get final product without converter, promptly utilize the original high-frequency tuner in the television receiver, in put, video detection, sound accompaniment and synchronous pulse extracting circuit.
Method about emission conversion and receiving conversion of the present invention can obviously be found out from the foregoing description.
Claims (7)
1, a kind of transmitting converter of pay TV, comprise the sync separator 3 that separates the synchronizing signal in the composite video signal, it is characterized in that also comprising that response forms device 4 from the switching pulse that the isolated line synchronizing signal of sync separator produces the row square wave, produce the visual paraphase control signal generator 5 of visual paraphase control signal according to the line synchronizing signal of separating from sync separator 3 and frame synchronizing signal, carry out the logical circuit 7 of logical process according to the output of switching pulse formation device 4 and visual paraphase control signal generator 5, the reversing phase switch 6 that selectively image video signal of relevant row is carried out paraphase according to the output of composite video signal and logical circuit 7 is so that do encryption to the TV signal of emission.
2, a kind of emission transform method of pay TV is characterized in that making selectively the image video signal of relevant row to carry out paraphase and launches.
3, a kind of receiving transducer of pay TV, comprise high-frequency tuner 11, the circuit 12 that contains intermediate frequency amplifier circuit, video detecting circuit, sound accompaniment and synchronous pulse extracting circuit is characterized in that also comprising that the image video signal to the relevant row after the paraphase carries out the contrary treatment circuit 13 of video of paraphase again.
4, receiving transducer as claimed in claim 3 is characterized in that also being provided with the modulation circuit again 64 that the audio signal of signal after handling through the contrary treatment circuit 13 of video and extraction from circuit 12 is synthesized and is modulated to the TV signal of high frequency.
5, receiving transducer as claimed in claim 3, it is characterized in that the contrary treatment circuit of above-mentioned video comprises frame squarer 21, row squarer 22, counter 23, logical circuit 24, two-way amplifier 26, export first gate-controlled switch 27 of control by one of logical circuit 24, by second gate-controlled switch 28 of another output control of logical circuit 24, adder 29, the clamper of controlling by SAND 25.
6, a kind of receiving conversion method of pay TV is characterized in that the image video signal that will receive the paraphase in advance in the TV signal carries out paraphase again and recovers former normal image.
7, receiving conversion method as claimed in claim 6, the corresponding square wave of cycle that it is characterized in that the row at the image video signal place by producing its width and paraphase in advance, control this image video signal and carry out paraphase again, and line synchronizing signal is kept intact by producing delegation's square wave.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 90101293 CN1018046B (en) | 1990-03-08 | 1990-03-08 | Transmitting converter and receiving converter of fee-television and converting method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 90101293 CN1018046B (en) | 1990-03-08 | 1990-03-08 | Transmitting converter and receiving converter of fee-television and converting method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1047179A true CN1047179A (en) | 1990-11-21 |
| CN1018046B CN1018046B (en) | 1992-08-26 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 90101293 Expired CN1018046B (en) | 1990-03-08 | 1990-03-08 | Transmitting converter and receiving converter of fee-television and converting method thereof |
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| Country | Link |
|---|---|
| CN (1) | CN1018046B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100359573C (en) * | 2002-06-05 | 2008-01-02 | Lg电子株式会社 | High-density optical disc, method for recording and reproducing encrypted data thereon |
| CN100433123C (en) * | 2004-12-31 | 2008-11-12 | 张群 | Secrecy display method and apparatus for screen |
| US7525889B2 (en) | 2002-06-05 | 2009-04-28 | Lg Electronics Inc. | Recording medium with a linking area including dummy data thereon and apparatus and methods for forming, recording, and reproducing the recording medium |
| US7545730B2 (en) | 2001-03-09 | 2009-06-09 | Lg Electronics Inc. | Read-only recording medium and reproducing method thereof |
| CN101114493B (en) * | 2002-06-05 | 2010-09-01 | Lg电子株式会社 | High-density optical disc, method for recording and reproducing encrypted data thereon |
-
1990
- 1990-03-08 CN CN 90101293 patent/CN1018046B/en not_active Expired
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7545730B2 (en) | 2001-03-09 | 2009-06-09 | Lg Electronics Inc. | Read-only recording medium and reproducing method thereof |
| US7656778B2 (en) | 2001-03-09 | 2010-02-02 | Lg Electronics, Inc. | Apparatus and method of reproducing data stored in a read-only recording medium |
| US7619961B2 (en) | 2001-03-09 | 2009-11-17 | Lg Electronics Inc. | Read-only recording medium and reproducing method thereof |
| US7542393B2 (en) | 2002-06-05 | 2009-06-02 | Lg Electronics, Inc. | Recording medium with a linking area including a sync pattern thereon and apparatus and method for forming, recording, and reproducing the recording medium |
| US7542405B2 (en) | 2002-06-05 | 2009-06-02 | Lg Electronics Inc. | High-density optical disc, method for recording and reproducing encrypted data thereon |
| CN100359573C (en) * | 2002-06-05 | 2008-01-02 | Lg电子株式会社 | High-density optical disc, method for recording and reproducing encrypted data thereon |
| US7558175B2 (en) | 2002-06-05 | 2009-07-07 | Lg Electronics Inc. | Recording medium with a linking area thereon and apparatus and methods for forming, recording, and reproducing the recording medium |
| US7577080B2 (en) | 2002-06-05 | 2009-08-18 | Lg Electronics Inc. | Recording medium with a linking area thereon and apparatus and methods for forming, recording, and reproducing the recording medium |
| US7599279B2 (en) | 2002-06-05 | 2009-10-06 | Lg Electronics Inc. | High-density optical disc, method for recording and reproducing encrypted data thereon |
| US7525889B2 (en) | 2002-06-05 | 2009-04-28 | Lg Electronics Inc. | Recording medium with a linking area including dummy data thereon and apparatus and methods for forming, recording, and reproducing the recording medium |
| CN101114493B (en) * | 2002-06-05 | 2010-09-01 | Lg电子株式会社 | High-density optical disc, method for recording and reproducing encrypted data thereon |
| US7872960B2 (en) | 2002-06-05 | 2011-01-18 | Lg Electronics Inc. | Recording medium with a linking area thereon and apparatus and methods for forming, recording, and reproducing the recording medium |
| US8014248B2 (en) | 2002-06-05 | 2011-09-06 | Lg Electronics Inc. | Recording medium with a linking area including dummy data thereon and apparatus and methods for forming, recording, and reproducing the recording medium |
| US8351315B2 (en) | 2002-06-05 | 2013-01-08 | Lg Electronics Inc. | Recording medium with a linking area including a synch pattern thereon and apparatus and methods for forming, recording, and reproducing the recording medium |
| CN100433123C (en) * | 2004-12-31 | 2008-11-12 | 张群 | Secrecy display method and apparatus for screen |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1018046B (en) | 1992-08-26 |
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