KR890000017B1 - Multiple signal transmission method and system - Google Patents

Abstract

The scrambling technique, includes modulating an in-phase component of at least one carrier signal in response to one and then another of several input signals in a sequence of time intervals. Parts but not all of the one and another of the input signals are carried by the in-phase component. A quadrature component of the at least one carrier signal is modulated in response to the one and another of the input signals in the sequence of time intervals such that parts but not all of the one and another of the input signals are carried by the quadrature component.

Description

Operation method and apparatus of television system

1 is a functional block diagram generally showing one embodiment of a television transmission and reception system according to the present invention;

2 is a functional block diagram showing in more detail the audio encoder and combiner of FIG.

FIG. 3 is a graphical representation of the fundamental versus audio spectrum produced by the embodiment of the invention shown in FIGS. 1-2.

4 is a functional block diagram showing in detail an embodiment of an audio encoder or scrambler according to the present invention.

5 is a graphical representation of scrambled audio signals produced by the encoder of FIG.

6 is a functional block diagram showing another embodiment of an audio encoder or scrambler according to the present invention.

7 is a graphical representation of the scrambled audio signal produced by the encoder of FIG.

FIG. 8 is a functional block diagram illustrating the audio decoder and selector of FIG. 1 in more detail. FIG.

9 is a functional block diagram showing in more detail an embodiment of the decoder and selection control device of FIG.

10 is a functional block diagram of an embodiment of a receiver rotating device and category code memory device according to the present invention.

The present invention relates to the transmission and reception of audio and video signals and more particularly to a method and system for transmitting and receiving multiple audio frequency signals with a video signal, preferably within a frequency band assigned to a single television channel for commercial television and subscriber television.

The transmission and reception of information in the frequency spectrum set up for television has advanced to the point that the viewer is provided with audio or video properties in addition to the regular audio and video signals associated with a particular television program. Normally, a regular television video signal is transmitted with the associated audio signal in the assigned frequency band of about 6 MHz. Recently, however, additional information has been transmitted and received with regular audio and video signals by the viewers, especially in Pressurized Television (STV).

For example, most STV systems include an scrambled video signal and an audio signal associated with the scrambled video signal for an affiliate program and an additional audio channel, commonly referred to as a Barker channel.

This Barker channel is transmitted at the regular audio center frequency in the band assigned to the television channel. This barker is typically used for messages related to unscrambled video available to all viewers and irrelevant to the scrambled subscription television program. Audio related to the scrambled subscribing television program is transmitted at a center frequency shifted from the normal audio center frequency and cannot be detected by a regular television receiver. Thus, a subscribing television system has a video signal at a fixed position in the assigned frequency band (but scrambled) and two audio at one position at a normal frequency position within the television channel frequency band and another at a position shifted from the normal television audio frequency position. It may include a signal.

The regular television bandwidth allocated to the feature channel may be used to transmit additional information related to or not related to the television program video given a title or other text data.

For example, in a teletitle system which gives a title, it is transmitted at the vertical interval of a regular television video signal or at any other convenient location of this signal. This additional information is broadcast in the regular television band assigned to the particular channel and detected by the television receiver by a special adapter or decoder to display the title or other textual material on the face of the television cathode ray tube (CRT).

Of course, to increase the amount of information available to television viewers during program broadcasts, other systems have been proposed that transmit additional information without exceeding the regular television frequency band assigned to a particular channel. For example, televisions and FM stations sometimes cooperate by simultaneously transmitting television programs over normally assigned television channels and their accompanying tones over assigned FM radio channels. Thus, a viewer can watch a program on a regular television receiver while listening to the accompanying sound in stereo using an FM receiver.

Similar systems have been proposed and are obviously being used to provide multilingual audio for certain television program videos. For example, in the system described on page 34 of TV WORD, published in July 1980, television signals are normally transmitted in the frequency range normally assigned to one television channel, and audio signals added in other languages are transmitted over the FM radio band. . Viewers can choose either FM radio bands or regular television audio, and can choose between two audios, which are different languages accompanying the program being viewed.

It is an object of the present invention to provide information in addition to regular television audio and video that a television viewer can select. However, the primary purpose is to provide such information within the normal frequency band assigned to the television channel.

It is also an object of the present invention to provide much more information than has ever been achieved without exceeding the allocated frequency bandwidth of a single television channel.

It is a further object of the present invention to add information to regular television audio and video in the frequency band assigned to a single television channel so that subscribers can select information in a desired format only by those who are entitled to receive it. To provide.

It is therefore another specific object of the present invention to provide a novel method and system for transmitting and receiving television signals in a regular frequency band assigned to a television channel through which a television video signal and at least three other signals can be transmitted and optionally received.

Another object is a new scramble and transmission technique for multiple signals, in which multiple signals are transmitted in the form of a minimum frequency bandwidth that can be received in the form of information by a regular receiver, but can be selectively used by qualified individuals with decoders. To provide.

It is a further object of the present invention to provide a novel television transmission and reception method and system for subscriber operation, in particular for subscribers to select between a plurality of multilingual audio sound tracks accompanied by television video program material.

It is a further object of the present invention that a highly secure transmission of STV program material is performed at a low level (relatively less secure scramble of the video portion of a television program) and at a higher level (more securely scrambled of the audio portion of the program) and a plurality of audio signals. One of them is to provide a subscription television system and method that can be selected by a qualified subscriber.

In brief, one aspect of the present invention is to modulate a plurality of input signals into one in turn and then into another in alternating form of in-phase and quadrature phases of at least one carrier signal, and to the in-phase or quadrature components as a whole. It is to scramble a plurality of input signals for safe transmission by not including one or another input signal. More specifically, the in-phase component of at least one carrier signal is determined by one and the next one of the plurality of input signals in the order of the time intervals in which one part of the input signal and one part of the other but not all of them are carried by the in-phase component. It is modulated in response. The at least one quadrature component of the carrier signal is carried by one or more parts of the input signal but not all of them by the quadrature component, and the in-phase and quadrature components are all one and the other of the input signal. Modulated in response to one of the plurality of input signals and one to the next in the same time interval order of carrying. The modulated in-phase and quadrature components are combined for transmission by, for example, combining the in-phase and quadrature components and modulating the second carrier signal with the combined signal. The order of time intervals preferably includes time intervals that change in duration in a predetermined pseudo-random manner.

Preferably, the input signals are information signals wherein at least one information signal is an audio program associated with a television video program.

According to one embodiment the four input signals are scrambled using the in-phase and quadrature components of the two carrier signals frequency shifted by an amount sufficient to prevent transmission interference. Thus, subscribers of the scrambled transmission system can choose between a number of available signals, including various language soundtracks accompanying the television video program.

According to another aspect of the present invention, the jingy audio and video program signals are transmitted according to respective normal audio and video signal frequencies of the television station frequency band allocated for transmission of a single television channel. Audio and video program signals are normal in the sense that they are transmitted at respective normal audio and normal video center frequencies assigned for transmission of audio and video signals within the normal television audio and video frequency bands. Simultaneously with the transmission of the regular audio and video program signals, a plurality of additional audio signals (i.e. at least two) are transmitted at the normal audio frequency, sufficiently from the normal audio center frequency so that there is no interference between the regular audio signal and the additional audio signal at the time of transmission and transmission. Transmitted in all television frequencies at least one center frequency displaced. Additional audio signals are also transmitted so that the transmission energy does not exceed the full television frequency band.

Another aspect of the invention includes a method and system for operating a television system for commercial television or STV service in a scrambled or unscrambled form, with regular and additional audio signals. Another aspect also includes methods for providing qualifications and other codes through addressing of individual recorders, including building and category selection (subscriber eligibility) methods and systems.

The above and other objects and advantages of the present invention will become apparent to those skilled in the art within the following detailed description, taken in conjunction with the accompanying drawings. The commercial television channel should be transmitted at the center frequencies to which the frequency bandwidth of about 6 MHz is always allocated and within which the audio and video signals are allocated. Most of its bandwidth is occupied by the video signal, leaving about 200-250 KHZ for audio information at the top of the band. The television video signal is functionally modulated by the video carrier with the normal ovideo center frequency of a particular television channel as functionally shown in FIG. 1 and described in detail below by the present invention. This video signal may or may not be scrambled, but its position and transmission in the frequency band may be entirely conventional. Thus, the video signal transmitted by the present invention may be received by a conventional television video receiver, but if it is scrambled or contains additional information, the video may be unpleasant or even invisible to view and the additional information may be lost and may be lost in the seat of the corrector. The above signal processing will not be possible.

Likewise, at least one audio signal is transmitted at the regular television audio carrier center frequency and received at a conventional television audio receiver. Since it is a "normal" arrangement in the frequency band of the television channel, this audio signal will be referred to as a normal audio signal hereinafter. Like other "audio" signals described herein, the information content of a regular audio signal can be changed from regular program audio or audio to video and innocent information. However, each "audio" signal referred to herein will be limited to the frequency range (eg 20-20,000 HZ, preferably 50-15,000 HZ) relative to the frequency range of the audio signals. Thus, in the context of the present invention, the term audio signal may refer to any signal whose frequency is limited to the audio frequency range. Such signals may include audio information associated with the program video signal (e.g., soundtracks of mono or stereo films), additional audio information associated with the video (e.g., one or more foreign languages of the film soundtrack), and program video signals. It may include information that is not related to (eg, control signals, facsimile information, etc.). As will be seen below, a plurality of non-normal audio signals are provided as composite television signals within a portion of the band allocated for audio transmission. These other audio signals are in the 200-250KHZ band where the carrier frequency is shifted from the normal audio signal carrier frequency but the synthesized audio is allocated for audio transmission in the frequency band of a single television channel.

1 shows one embodiment of a system according to the invention in which signals made at a television station or other central location are transmitted to a subscriber location (or viewer location in case of unsubscribed service). The transmission from the television station to the subscriber's location is done by other suitable means, such as public broadcasting or cable, as illustrated. However, as will be appreciated, certain aspects of the present invention may equally apply to any type of transmission, while other aspects, in particular the scramble techniques and frequency spectrum / conservation aspects described below, may be more applicable to broadcast systems. Although the present invention has been described with respect to the US commercial television transmission standard, the principles of the present invention are applicable to various television signal transmission formats including those used in other countries and satellite MDS transmission.

Referring to FIG. 1, the jinggyu audio signal source 10 is provided to an audio encoder and combiner 12, which describes the normal audio signal N.AUDIO later in detail. Similarly, audio signals 10A, 10B and --10N are provided as audio encoders and combiners 12 for audio signals AUDIO.A and AUDIO.B--AUDIO.N. An audio control signal ACTL is provided to the audio encoder and combiner 12 from the audio encoder control described in detail later. The composite audio signal CAUD is fed from the encoder and combiner 12 to the conventional exciter circuit and transmitter circuit 16. In a typical television system, the audio signal is supplied to the FM exciter and transmitter since the audio signal is transmitted as a frequency modulated signal.

The video equipment in the television station includes a video signal source 18 which provides a video signal VID to the video encoder 20 in a subscription system having video scramble of a certain program material. In the scrambled video system, the video encoder control circuit 22 provides the video control signal VCTL to the video encoder 20 and any video signal VID or SVID that is scrambled or not scrambled is supplied from the video encoder 20 to the exciter and transmitter 16. In a regular television system, this information is transmitted in amplitude modulation for video signal transmission so that the video signal VID (SVID) is supplied to the AM exciter and transmitter. Of course, a video encoder control circuit is not required in a system without video scramble, such as a commercial TV system or a subscription service in which a humidifier pays only a video service.

At the viewer's location, AM and FM receivers receive and detect respective video and audio signals from the television station. The AM receiver provides a VID (SVID) signal to video decoder 26, which in turn is provided to a conventional modulator 28 to remodulate the video output signal VIDEO OUT to a particular television channel frequency. The RFM receiver provides the combined audio signal CAUD to the audio decoder and selector 30, and the selector 30 sequentially provides the audio output signal AUDIO OUT to modulator 28. The combined audio and video modulator output signal is fed to the television antenna terminals of a conventional television set.

These video and audio decoders are provided by the decoder and selector control circuit 32 in which various control signals are described in detail later. The signal from the decoder and selector control circuit 32 in the subscription system is provided to a suitable billing mechanism 34 of suitable conventional design.

In one such billing mechanism, for example described in US Pat. No. 4,163,254, billing information is accumulated in billing mechanism 34 for periodical questions across the evolutionary line. As will be recognized later, such billing mechanisms will be readily available with the system when certain information by the subscriber is paid on the basis of the selection and use of the old information.

In operation, the regular audio signal and the plurality of additional audio signals are combined by an audio encoder and combiner 12 to form a composite audio signal CAUD under the control of the audio encoder control signal ACTL. In the register embodiment of the present invention, four audio signals added to the regular audio signal are combined to form a composite audio signal. However, it will be appreciated that other numbers of audio signals added to the regular audio signal may be used to form the composite audio signal.

As will be seen later, the audio encoder and combiner 12 combine multiple audio signals over a frequency baseband spectrum that is no greater than half of the bandwidth allocated for transmission of a regular television channel. In this way the total bandwidth of the frequency modulated signal transmitted by the FM exciters and transmitters does not exceed the allocated bandwidth. In addition, various audio signals are provided in the base-to-audio spectrum in a form that can be easily distinguished by relatively inexpensive hardware. For example, these audio signals are sufficiently frequency shifted from one another so that they can be separated by relatively inexpensive conventional filtering techniques. Moreover, by using in-phase and quadrature components of a single carrier, different types of audio signals can be provided so that they can be easily distinguished and detected.

The video signal VID from video signal source 18, like any other standard video signal, will be used to modulate the conventional AM exciter and transmitter. However, as described above, it is desirable to scramble the video signal prior to transmission. Thus, a video encoder can be provided for this purpose.

Video encoder control circuitry 22 determines whether video encoder 20 scrambles the video signal in any suitable way, and further determines how scramble is achieved. Of course, the MPEG control circuit 22 would not be required if suppression synchronization or A.C signal insertion techniques were used.

The composite television signal, i.e. the transmitted AM video and FM video signals, are received by the AM and FM receiver in any suitable conventional manner, providing a composite audio signal and a video signal of the desired intermediate frequencies, respectively.

Video decoder 26 does not scramble the received video signal when the video signal is scrambled (ie, the SVID signal is transmitted and received).

If video decoder 26 demodulates all video signals to provide baseband video signals and synchronous or polar scrambles are used according to the scrambled format typically used, then the video output signals reconstructed sync or polarity and then reconstructed as basic. Provide VIDEO OUT. This video output signal is re-modulated to the desired television channel frequency, which may or may not correspond to the frequency band of the originally transmitted television signal. Indeed, according to one aspect of the present invention, modulators for audio and video output signals are fixed at a specific frequency (e.g., channel 3) corresponding to a television channel and AM and FM receiver 24 do not change the channel selector of the television set. It includes an all-channel tuner that allows all channels to be received and viewed. (See Figure 10)

To select a different television stand, i.e., a different television channel, is to change the AM and FM tuner to select the desired channel without having to change the channel selection of the television set. In this way, remote control or other devices described below can be easily provided to existing television sets.

The synthesized or combined original audio signal CAUD received by the FM receiver is supplied to the audio decoder and selector 30, and a single audio signal is selected as the audio output signal AUDIO OUT. The selection of the audio output signal is controlled by the viewer via the decoder and selector control circuit 32 which will be described later in detail. The decoder and selector control circuit 32 is also provided for the selection of one or more additional signals to equipment other than output jacks or regular television receivers.

Selection of a particular audio signal or plural signals and / or reception of a scrambled video signal for descrambling and viewing is recorded by the billing mechanism 34 for billing purposes as described above. In this regard, the information contained in the video program signal, such as program identification, is supplied to the billing mechanism as virtually illustrated to completely record the viewer's selection.

2 shows a composite audio signal CAUD as a regular audio signal N.AUDIO. And an audio encoder and combiner 12 of FIG. 1 in which and 4 additional audio signals AUDIOA-AUDIOD are encoded and combined for transmission. In the embodiment of FIG. 2, the audio signal is not safely scrambled. It will be appreciated that all signals except regular audio N.AUDIO will be displaced within the audio frequency band from the normal television audio center frequency, and therefore a special device is needed to detect additional audio signals.

Additional audio signals are safely scrambled by adding a scramble circuit to the front of the audio encoder and combiner. Thus, even if the device has a device capable of receiving and detecting additional audio, it cannot be used unless the subscriber device has the proper descrambling capability.

In FIG. 2 each of the normal and additional audio signals is filtered by band filter 40-40D. Each filter of the 40-40D is a conventional filter that limits the frequency range of audio signals between 50-15,000HZ, and is in the audio frequency range and transmits sufficiently high fidelity voice information.

Output signals from each of the filters 40-40D are applied to each pre-emphasis circuit 42-42D. These preemphasis circuits are conventional circuits with a time constant of 75 μs at the relevant frequency. The low frequency stages of the audio signals are therefore of relatively constant amplitude up to a frequency of about 2.1 kHz. At the 2.1 KHZ break point, the amplitude of the audio signal is "emphasized" and generally increases linearly (see Figure 3).

The output signal from the preemphasis circuit 42 is applied to the conventional summation or combination circuit 44 and the output signal from the preemphasis circuits 42-42D is applied to each conventional mixer 46A-46D. For example, the mixers 46A-46D are conventional dual equilibrium mixers. The baseband audio spectrum of each of the signals from 42-42D with Preemphasis is essentially the same shape and corresponds to the overall representation of the spectrum indicated by NAUD in FIG.

The output signals from mixers 46A-46D are each pre-emphasized audio signal biaxial band, suppression carrier (DSB-SC-AM) amplitude modulated to one of two center frequencies, whether in pilot and in-phase (I). 90 ° phase difference or quadrature phase.

In this regard, the pilot tone of the desired frequency is applied to each conventional phase carrier generator 48 which generates an in-phase signal I and a quadrature-phase signal Q at each of two separate frequencies related to the pilot tone frequency. . These signals I and Q signals at each of the selected frequencies are used as carriers in the DSB-SC-AM multiple audio method described herein. Pyrottones are also added to summing circuit 44 to transmit as part of the synthesized audio.

In the illustrated embodiment the selected frequencies are related to the horizontal synchronization frequency F _H of the television video signal. This is because this frequency is convenient and has a uniquely suitable multiple for the system of the present invention.

In particular, the frequency 5F _{H / 2 (} 39.335 KHZ) is selected as one carrier frequency and the frequency 10F _{H / 2 (} 78.67KHZ) is selected as the other carrier frequency. As will be seen later, this guarantees about 10 KHZ between each audio band in the composite baseband audio spectrum and also enables the transmission of five audio signals (using I and Q components) within the audio frequency bandwidth allocated in the television channel band.

With continued description of FIG. 2, in-phase carrier signal 5F _H / 2 (0 °) is applied to mixer 46A and quadrature phase carriers of the same frequency 5F _H / 2 (98 °) are applied to mixer 46B.

In-phase carrier signal 10F _H / 2 (90 °) is applied to mixer 46D. These I and Q signals from mixers 46A and 46B are combined by conventional summing circuit 50 and the I and Q signals from mixers 46C and 46D are applied to the same summing circuit 52. The output signal from the summation circuit 50 is applied to one input terminal of the summation circuit 44 via a conventional low pass filter 54. The output signal from the summation circuit 52 is applied to the other input terminal of the summation circuit 44, and the output signal from the summation circuit is applied through the conventional low pass filter 56 as the synthesized audio signal CAUD.

The signal from combiner 50 is that AUDIO A and AUDIO B are synthesized with I and Q components of carrier 5F _{H / 2 (} 39.335KHZ). The highest desired frequency of this composite signal will be about 54.335KHZ. This is because synthetic audio can reach up to 15KHZ (ie 24.335KHZ-54.335KHZ) on both sides of the carrier. Thus, the low pass filter 54 passes signals with a frequency of 54: 335 KHZ or less and blocks (or at least substantially attenuates) signals with all higher frequencies. This results in overall indication of the frequency spectrum with the graph AUDAB 'in FIG. 3 within the baseband audio frequency spectrum.

Similarly, combiner 52 synthesizes audio signals AUDIO C and AUDIO D modulated with I and Q components of carrier 10F _H / 2. The intermediate frequency of this synthesized audio signal AUD CD 'is 78.67KHZ and synthesized over 63.67KHZ-93.67KHZ. Therefore, when this synthesized signal is combined with the synthesized signal AUD AD 'and the pre-emphasized regular audio NAUD', the synthesized audio is filtered out and passes only signals below the highest expected frequency of 93.67KHZ (filter 56).

Thus, the synthesized baseband audio frequency spectrum of the synthesized audio CAUD is the full baseband spectrum shown in FIG. This audio spectrum contains a pre-emphasized regular audio signal (AUDN) within the baseband frequency range 50-15,000 Hz with a flat response between 50 Hz-2100 Hz and then an emulated response.

The additional audio signals are included in the spectrum of the DSB-SC-AM signals in the I and Q phases, which are roughly centered on the pilot frequency and are twice the frequency of the pilot frequency. The pilot signal itself is provided as part of the heterogeneous spectrum and, as shown, the pre-emphasis of each additional audio signal appears as a flat response up to 2100 Hz on each side of the center frequency, followed by a rising slope.

Since the video horizontal frequency F _H and its harmonics can cause interference problems, they are represented virtually in relation to the baseband audio spectrum. For example, AM to PM conversion is possible and occurs at the high power stage of the video AM transmitter. These PM sidebands are present at fH ', 2fH' and higher harmonics. When an intercarrier is used at the receiver, the PM sidebands around the video carrier are half-modulated up to the 4.5 MHz intercarrier bits used for FM detection. In FM detection, PM sidebands generate spurious tones in the detected audio signal. For a standard broadcast system, these pseudo tones are not a problem because they have F _H (15.734 Hz) or higher harmonics and a 15KHz audio band. This pseudo tone will appear virtually as shown in FIG. To eliminate them as a problem, the decoder according to the present invention does not use intercarrier detection and instead detects that the audio intermediate frequency (IF) 41.25KHz is downconverted to 10.75KHz, filtered, amplified, limited and then detected. You will know. Thus there will be no significant intermodulation of the PM of the video carrier to the audio signal.

As described above with reference to FIG. 1, the synthesized audio signal CAUD is applied to a conventional FM filter (modulator) and a transmitter for broadcasting. The exciter / transmitter may comprise pre-emphasis which causes pre-emphasis shown in FIG. 3 for the NAUD 'signal with a single audio of the transmission frequency. However, according to the present invention, a slightly different emphasis method is employed.

The initial pre-emphasis of the baseband audio is achieved as described above, and instead of the pre-emphasis of the regular exciter, the electro-band-to-audio spectrum ranges from a 50 Hz to about 33,000 Hz flexure point (a regular baseband transmitted in a television system). It is preemphasized by a time constant that represents the flat response up to the baseband audio above the audio range, and a pre-emphasis response that slopes above 33 Hz. For the audio FM modulator or exciter of the broadcast television system according to the illustrated embodiment, the pre-emphasis time constant of the exciter (which is also achieved by conventional inductive load, etc.) is modulated to an order of 4.823 seconds to achieve this 33 KHz bulek point. Will be.

In addition, it is preferable that the FM exciter / transmitter according to the present invention be set to change in a wide band operation at a modulation frequency significantly lower than 35 KHz at a modulation frequency of 33 KHz or more. This can be accomplished in any suitable conventional way, for example by setting the transmitter modulation index for a deviation of about 18.734 Hz when a tone of 93.671 Hz is applied at an appropriate level. The bandwidth occupied by the transmit carriers modulated by the two-band low-frequency, narrow-band high-frequency transmission method is approximately 189.102 Hz (2 [880 + 93.671]) ± and fits within the 200-250 KHz band allocated for television audio signals.

According to the present invention, the additional audio signals can be scrambled so that only authorized or "qualified" subscribers can use the information available as additional audio signals. One method of scrambled audio signals for secure transmission in the case of two additional audio signals is illustrated in FIGS. 4-6.

A first information signal A such as a Spanish speech signal combined with a video signal transmitted with reference to FIG. 4 is applied to one input terminal of a conventional electronic selector switch 60.

The information signal A is also applied to one input terminal of the same selector switch 62. However, if this signal A is applied to the normally closed (eg normal conduction) side of the switch 62, the signal A is applied to the opposite side of the switch 62 or to the normally open (normally nonconductive) side. In this way the same control signal (e.g. binary signal) applied to switches 60 and 62 causes signal A to appear at the output of switch 60 and at the same time block what appears at the output of switch 62 and also for any particular control signal level. Is established.

A second information signal B, such as a blow plate of signal A, is provided to the second input terminal of the switch 60 and the opposite terminal of the switch 62. Thus the output signal at the output of switch 60 will always be information signal B when the control signal is at level 1, at the same control signal level control signal B will be blocked from the output terminal of switch 62 and signal A will appear at this terminal. . Thus, it will be appreciated that for any control signal, signal A appears at the output of switch 60 while signal B appears at the output of switch 62. When the control signal is changed, there will be an opposing output signal condition.

Conventional pseudorandom binary order (PRBS) signal generator 64 provides control signals for switches 60 and 62 as shown. In response to the clock signal, the PRBS generator provides an output pulse having a pulse width that varies in a constant repeating pattern. However, this pattern repeats after a sufficiently long period of time without any discernible logic sequence and the entire pattern appears random.

This PRBS generator signal pattern can be changed in accordance with the initial code that is substantially loaded into the PRBS generator by reset pulse RESET as shown. Thus, this reset pulse starts the PRBS generator at one point in the pseudorandom order that is resolved by the initial code, and the pseudorandom order proceeds in response to the CLOCK from that point. As you will see later, the pseudorandom pattern at the remote location is clocked in the same phase as the clock signal and is also clocked at the same rate and initialized by the same initial code at the same reset time (of course, relative to the timing of the received audio). To occur simultaneously.

The PRBS generator is activated or deactivated by each STV signal. This STV signal allows the PRBS generator to generate a pseudo-random order and scrambles the signals A and B. The STV signal stops the operation of the PRBS generator to remove the scramble. If only two additional audio signals are provided as shown in Fig. 4, it can be appreciated that only the NAUD 'and AUD AB' portions of the baseband audio spectrum are required to be used. Similarly, only the AUDIO A and AUDIO B channels of the encoders and combiners 12 of FIGS. 1 and 2 need to be provided. It should be noted, of course, that only two additional audio signals can be used with the AUDIO A and AUDIO C channels of encoder and combiner 12 and that these two additional audios are transmitted with I modulation only, eliminating combiners 50 and 52. .

FIG. 5 graphically shows the timing and signal contents AUDIO A and AUDIO B signals provided by the scrambler of FIG. 4 in relation to the control signal from the PRBS generator 64 in scrambled or STV mode. When the binary one signal level is provided by the PRBS generator, the AUDIO A signal has the information signal B while the AUDIO B signal has the information signal A. When the output signal of the PRBS generator is switched to the binary zero level, the AUDIO A signal has the information signal A and the AUDIO B signal has the information signal B.

It will be seen that the AUDIO A or AUDIO B signals do not have complete information signals, but they together have both information together. Since both the AUDIO A signal and the AUDIO B signal are transmitted, a suitable reversal of the scramble method provides each information signal without distortion, which can be perceived in its entirety by a relatively simple filter. It will be appreciated that proper inversion cannot be achieved without the proper initial code, the appropriate reset pulse, and the appropriate clock signal (in addition to an audio receiver capable of receiving and detecting additional audio transmissions). Therefore, the scramble method is extremely safe just by adding two audio signals to the regular audio.

Of course, when four additional audio signals are provided and scrambled, unauthorized descrambling is practically impossible. For example, four information signals SIGNAL A-SIGNAL D are applied to an encoder (scrambler) according to the present invention as shown in FIG. The illustrated encoder includes four switching circuits 68-A-68-D (e.g., one switch matrix) connected in a conventional manner such that each circuit selects one of the four input signals as the output signal. It will be appreciated that these switching circuits are controlled so that at any instant each of the four information signals is selected as a source signal from only one switching circuit as shown in FIG.

In FIG. 6, the switching circuits 68 receive four additional information signals SIGNAL A-SIGNAL D and select one as the output signal AUDIO A in response to the control signals "0-3". This " 0 " control signal closes switch " 0 " in circuit 68, connecting the first input terminal to the output terminal and applying SIGNAL A to the output as an AUDIO A signal. Similarly, the control signal "1" closes the combined switch "1" in circuit 68A, connects the second input terminal to the output and applies SIGNAL B to the output. The control signal "2" connects the third input terminal SIGNAL C to the output terminal, and the control signal "3" connects the fourth input terminal SIGNAL D to the output terminal.

Control signals " 0-3 " are generated in any conventional manner in response to the PRBS signal from the PRBS generator of FIG. For example, the PRBS preference and CLOCK signals described above in connection with FIG. 4 are applied to a logic circuit 70 including conventional logic gates.

This logic circuit generates a "0" control signal in response to the zero logic level of the simultaneous binary of the PRBS signal and the CLOCK signal. (E.g., while the "1-3 signals are at the zero level, the" 0 "control signal is at a high signal level. The "1" control signal is generated when the CLOCK signal is binary "1" and the PRBS signal is binary 0. The "2" control signal is generated when the CLOCK signal is binary 0 and the PRBS signal is binary 1. Is generated when both the CLOCK signal and the PRBS signal are binary 1. In this regard, the logic circuit 70 operates like a conventional binary.10 decoder.

The information signals SIGNAL A-SIGNAL D are also applied to the switching circuits 68 B-68 D, but to the other input terminals of each switching circuit. Thus, each switching circuit 68 A-68 D is the same and connected together for a specific control signal, but the output signal of each switch is different for that particular control signal. For example, as shown in FIG. 7, when the CLOCK signal is high level (binary 1) and the PRBS signal is low level (binary 0), the control signal "1" is generated and the respective information signals B, A, D And C are supplied as AUDIO A, AUDIO B, AUDIO C 'and AUDIO D output signals. Whenever the CLOCK and / or PRBS generator output signal is changed, the information signal included in the audio output signal changes at random.

The embodiment of the encoder shown in FIG. 6 operates in isochronous increments between audio signal content changes rather than the pseudo random increments produced by the two signal embodiments of FIG. Hence, the encoding is in the pseudorandom nature of the audio signal content, not the typing. However, it should be noted that additional elements of safety are provided for the four signal embodiments by introducing pseudo random time intervals between signal content changes in addition to the pseudo randomness of the described content. This can be achieved, for example, by using a second pseudorandom bit order generator instead of the CLOCK signal as input to logic circuit 70 or in any suitable way.

FIG. 8 details the audio decoder and selector and control circuits 30 and 32 at the subscriber location in the FIG. 1 embodiment. In FIG. 8, the synthetic audio signal CAUD (IF), which is the intermediate frequency of the FM receiver (shown as 24 in FIG. 1) and is pre-emphasized by the FM station / transmitter in a television station, is conventionally accompanied by the local oscillation signal LO. Is applied to 80's double balance mixer. The synthesized audio signal in the illustrated embodiment is an intermediate frequency of 41.25 MHz and mixed with a local oscillator signal of 30.5 MHz. This provides 10.75 MHz of intermediate frequency (I.F.) synthetic audio (along with other mixtures) to the output of mixer 80.

This I.F. signal from mixer 80 is applied to the conventional bandpass amplifier limiter 82 and the output signal from the limiter 82 is applied to the conventional discriminator 84. Bandpass amplification limiter 82 and discriminator 84 are designed to operate at an intermediate frequency of 10.75 MHz. Synthetic audio of 10.75 MHz I.F. is amplified and limited conventionally by circuit 82 and this FM is conventionally detected by discriminator 84 (eg by quadrature FM detection).

The composite output signal from the discriminator 84 is thus a pre-emphasized composite audio signal. The conventional de-emphasis circuit 86, with a 4.8228 μs time constant to match the time constant of the exciter / transmitter, desynthesizes the synthesized audio signal to provide the synthesis provided at the outputs of the audio encoder and combiner 12 of the first and second degrees. Create an audio CAUD.

The illustrated embodiment of the audio decoder and selector 30 of FIG. 8 is arranged to handle four audio signals in addition to the regular audio signal. The normal audio signal is simply detected in the synthesized audio CAUD by filtering through a low pass filter 88 having an upper cutoff frequency of 15 KHz. The signal from filter 88 is the NAUD signal of FIG. 3 and after being de-emphasized by a conventional de-emphasis circuit 90 having a 75 μS / time constant (2.1 KHz bulek point), the signal has a flat frequency response. The audio signal is NAUD. This NAUD signal is applied to one input terminal of the conventional two input terminal selector switch 92 indicated by the STV switch in FIG.

Synthetic audio signal CAUD is also applied to band limiter 94 to detect pilot tones of 39.335KHz, and to four identical audio channels, each containing a conventional bandpass amplifier 96 and a conventional double balanced mixer 98. Amplifiers 96 and mixers 98 are labeled 96 A-96 D and 98A-98 D, respectively, to indicate the audio signal channel they are combined with. Each bandpass amplifier is designed with a lower cut-off frequency of about 24 kHz and an upper cut-off frequency above the highest frequency of the synthesized audio to pass only AUR AB 'and AUD CD' signals (Figure 3).

The pilotton detected by the bandpass limiter 94 is applied to a conventional quadrature phase generator 100 that generates in-phase and quadrature carrier signals at frequencies of 5F _H / 2 and 10F _H / 2. The in-phase carrier signal of carrier frequency 5F _H / 2 from generator 100 is applied to mixer 98A, and the quadrature phase signal of sub-frequency is applied to mixer 98B. In-phase and quadrature carriers of frequency 10F _H / 2 are applied at right angles of mixers 98 C and 98 C.

The output signals from mixers 98 A-98 D are respective baseband audio signals AUDIO A-AUDIO D pre-emphasized by each of 42 A-42 D of the circuit of FIG. These signals are moderately filtered (not shown) and applied to the inputs of the audio program selector switch 102 to remove demodulation components above 15 KHz. The audio signal selected by the switch 102 is suitably de-emphasized by the conventional de-emphasis circuit 104 having a time constant of 75 μS. The selected audio output signal is applied to the STV input terminal of the switch 92 to be selected as the audio output signal of the STV mode after being de-emphasized.

In the system according to the invention in which additional audio signals are transmitted in a non-scrambled form, the switch 102 is an electronic or mechanical switching device that selects a desired one of only four AUDIO signals. The selection between the regular audio signal and the selected one of the additional audio signals can also be achieved in the same way by adding a switch contact to switch 92 or switch 102. Moreover, one or more additional audio signals are applied to the output jack of the decoder (always available), i.e. a soundtrack transmitted in stereo has one channel transmitted as a regular audio signal and another channel transmitted as an AUDIO D signal. And the AUDIO D signal is obtained from the auxiliary jack. Similarly, the government that operates some of the peripherals is provided by auxiliary jacks.

In the STV system, the regular audio signal is an unscrambled signal as shown in the illustrated embodiment, and as an audio output signal whenever the STV selection signal (e.g., a subscriber-controlled STV selector switch) is in the "NON-STV" mode (STV). Is selected. In normal STV operation, the regular audio signal is a Barker signal and the video signal is scrambled. However, the scrambled video appears on the television display until the video signal is received by the subscriber for descrambling. When the subscriber selects STV or unscrambled mode, this video signal is unscrambled and one of the additional audio signals is provided as an audio output signal. Of course, this audio selection method in response to this STV signal can be used whether or not additional audio signals are scrambled, but it is thought that they are scrambled to add an extremely high level of safety to the system.

In STV systems or other subscriber systems (shown in FIGS. 4-7), which are desirable for transmitting scrambled additional audio signals, the audio program selector switch includes a scramble release circuit controlled by an audio select signal. For example, a subscriber inserts an initial code into his decoder and this code is applied to a conventional PRBS generator (FIG. 4) at the transmitting station. Alternatively, the code is periodically transmitted to the subscriber's location by addressing each decoder over a telephone line, such as US Patent No. 4,163,254, handed over to the assignee of the present invention, or by providing this code as part of the transmitted signal. do. The CLOCK and RESET signals required for the PRBS generator of FIG. 4 may be derived from the transmitted video signal or may be a special code inserted into the signal (e.g., with a vertical blanking interval).

Therefore, the PRBS generator, which is synchronized with the PRBS generator at the transmitter position, is provided in the decoder. For example, the decoder and selector control circuit 32 of FIG. 1 includes a PRBS generator 110 as shown in FIG. The PRBS signal is applied to logic circuit 112 to generate " 0-3 " control signals in conjunction with CLOCK SIGNAL as described above with respect to FIG. In this regard, the audio program selector switch 102 of FIG. 8 includes the switching matrix as shown in FIG. 6 and reverses the coding process in response to the "0-3" control signals to provide the information signals SIGNAL A-SIGNAL D. do. The selector switch 114 is rotated by the subscriber to provide signals A, B, C or D to conventionally select the desired one of the audio information signals at the output of the switch 102 of FIG.

Signals A, B, C and D are sampled at switch 114 to provide an SV select signal STV and an STV switch or other subscriber switch is provided for this purpose.

In addition to the regular audio signal, having four audio signals is achieved within the regular television audio signal band and all television bands assigned to a single television channel, thus providing numerous advantages for both regular non subscriber television systems and subscriber systems. It is. In a non-subscriber system, television programs can be transmitted, including Spanish soundtracks, French soundtracks, and / or other language soundtracks, with regular audio signals having English program soundtracks, and viewers can select from them.

In areas with mixed English and Spanish residents, such as Los Angeles, the regular audio signal provides one language and one additional audio signal simultaneously provides another language. In addition, if many Japanese live, Japanese is provided as additional audio signals. At the same time, the remaining audio signals may have information news or stock trading services for other services, such as heading information and / or facsimile services that drive the character generator to provide headings inserted into the video (e.g., received additional audio signals). These latter types of services (associated with a printer driven by the information signals in it) will be subscriber services that are paid periodically or by subscription. For subscriber service, it is desirable that only qualified subscribers can use the transmitted information even if the accompanying video signal is not scrambled by scrambled additional audio signals. In other words, the subscriber service may not change the basic television service (ie, regular audio and video) by that channel that will contain only additional audio signals.

In such a subscriber system, each use of the additional audio signal can be recorded for billing purposes. Thus, this billing information can be collected on a per-will basis. At the same time, the code necessary to descramble the audio signal may be changed after the subscriber has confirmed that he or she is still entitled to the subscriber audio programs and / or services.

According to another aspect of the invention, the same monthly payment may be deducted for the programs and services, but different types of programs and services are priced differently so that the subscriber is paid according to the types of programs and / or services he subscribes to.

Program Identification, as shown in US Patent Application Nos. 920,846 and (now Patent No. 4,225,884) by Robert S. Block et al. Assigned to the assignee of the present invention (the disclosure of which is described herein by reference) Only those program signals that are transmitted with the program signals and have any identification codes at the subscriber station with the corresponding code at the subscriber station can be used. In a system such as a block, the program identification signals in the program information signals are detected and compared with signals generated locally by the subscriber's "category selector".

In this way a subscriber having a category selector containing code for all categories of the program can receive and unscramble all transmitted programs. However, the lock out feature provides the subscriber with the ability to prevent unauthorized descrambling of certain categories of programs. Likewise according to one aspect of the present invention program identification codes may be transmitted with program signals (ie with a television program comprising audio and video or only a special audio service). It is detected at the subscriber's location and compared with localized signals to determine whether the subscriber is entitled to unscramble the particular program.

As in the patent application by Block et al., These program identification signals may be different for each program or for different categories of programs so that each program can be individually identified (eg they are also used for billing). have. Alternatively, the category code comparator may be set to accept a plurality of different program codes as contained in one category of viewer's qualification. The categorization method for coding or comparison is suitable for simplicity in a well thought out flat fee billing system, but any method may be used. Furthermore, the program identification signals can also be utilized as code used to scramble and unscramble the program signals. That is, for example, by using different identifiers for different program categories and providing the subscriber with only those identifiers selected prior to the viewing period, the subscriber can view and / or view the category or audio service of their program with pre-selected identifiers. Or restricted use.

The identification codes as described above are described in one embodiment of the present invention by separately addressing the decoders and by loading their codes via the subscriber's decoder address transmission and then loading the codes of the categories of qualified programs that the subscriber uses. To the decoders.

As shown in FIG. 10, if the address codes and qualification codes are transmitted as part of the video signal (e.g. at vertical intervals), all channel tuners 120 of the remote control are preferably conventional electronics and the AM and Controls channel tuning of FM receiver 16. The unscrambled or scrambled video signal VID (SVID) from the receiver 122 is applied to the address decoder and comparator 124 and to the code detector and memory 126.

This address detector and comparator detects an address in the incoming video signal and compares the stored address with the detected addresses assigned to the subscriber decoder. Upon successful comparison, the address detector and comparator 124 activates the code detector and memory 126 so that subsequent codes in the video signal are detected and stored in memory for use in the video and / or audio decoders 26 and 30.

In the illustrated embodiment, the CLOCK and RESET signals used for the audio decoder and the selector 30 are also transmitted as part of the video signal. For example, the CLOCK signal may be a code and a periodic signal transmitted at a vertical or horizontal sync pulse or a vertical blanking interval. Similarly, the RESET signal may be a specific sync pulse or a special code transmitted at the vertical retrace interval. Accordingly, the video signal VID (SVID) is also applied to the sync or code detector 128 to generate a CLOCK signal, and the reset code detector 130 detects the RESET signal. This video signal is also applied to video recorder 26 as shown in FIG. 1 to descramble the SVID signal in the scrambled video system.

Note that if addresses and codes are transmitted therein, it will be necessary to demodulate (detect) the video signal in order to generate a baseband video. Thus a separate video detector (not shown) is used before address detector and comparator 124 and other code detectors 126,128 and 130. However, it is necessary to obtain baseband video for the purpose of descrambling this video (e.g. when video inversion is used to scramble or when it is necessary to reshape the sync to provide a suitable video signal to the TV set), thus making it more practical. Will use baseband video signal from video decoder 26 applied to address and code detectors 124, 126, 128, and 130 as opposed to the VID (SVID) signal as shown.

Referring back to FIG. 10, the power switch 132 on the subscriber decoder supplies power to the video decoder 26 so that power continues to be supplied to the circuits 120-130 (when video decoder 26 provides the baseband video signal to detectors 124-130). Connected).

The power switch 132 also supplies an OFF signal to the tuner 120 to indicate when the subscriber tuner is turned off. This OFF signal is conventionally controlled by the tuner so that the tuner is set to a predetermined television channel setting (e.g., channel 3) when the power switch is turned off.

It is believed that the categories of programs for which subscribers express their desire to subscribe are remembered by addressing the decoder in the first embodiment or after installation. However, the subscriber will want to add or delete categories after a certain period of use. Thus, shortly after installation or when the subscriber has expressed a desire to change category qualification, an address code for that subscriber's decoder at another time before the new viewing period begins is transmitted as part of the video signal.

This address code in the video signal is compared with the address detected and stored by the address detector and comparator 124. If the addresses match (preferably within some tolerance), the code detector and memory 126 are activated by the ENB signal and the category codes following the address code are detected and stored by the code detector and memory 126.

These memorized category codes allow the subscriber decoder to successfully scramble and use scrambled signals in one category but not scrambled signals in another category. For example, these category codes may be unscrambled for the audio decoder and selector 30 and / or for video decoder 26. Alternatively, the initial codes and descrambling codes for audio and video decoders are provided in another way that can be changed more frequently than the category codes. Of course, the safety concerns are alleviated if the category codes for various categories are changed periodically. When this latter method is employed, for example, the category codes stored by the circuit 126 are compared with the categories in the received signal to enable or prohibit scramble of the signal. · ·

It will be appreciated that the scramble and I / Q transmission methods described herein are used for secure transmission of signals other than video. For example, video signal transmission via satellite uses in-phase and quadrature components of a carrier signal and alternately modulates two different video signals for secure satellite transmission. It will also be appreciated that scramble codes for video and / or audio information are generated and transmitted in various ways. For example, the PRBS generator at the transmission position is of free operation and its status is transmitted periodically so that the PRBS generator at the receiver position is synchronized with the transmitter. The PRBS codes are also provided in many ways, including how the described video signal or audio signal is transmitted.

It will be apparent from the above description that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the embodiments disclosed herein are intended to be illustrative and not restrictive and the scope of the present invention is indicated by the appended claims rather than the foregoing description and therefore is within the meaning and range of equivalency of the claims. Changes are intended to be included within the scope of the claims.

Claims (30)

If within a television channel bandwidth, transmitting a television video program signal and a plurality of television audio program signals each combined with the video program signal: receiving the transmitted television video program signal and the plurality of audio program signals; And selecting one of the plurality of television audio program signals and supplying the selected one of the plurality of audio program signals together with the television video program signal to the television video display and speech generating means. Way. 2. The method of claim 1, wherein the transmitting step transmits the television audio program signal and the television video program signal within respective regular television audio and video signal bands of all television frequency bands allocated for a single television channel, wherein the audio and Transmitting video program signals into respective regular audio and regular video center frequencies assigned for normal transmission of audio and video signals, respectively, into the regular television audio and video bands: within the all television frequency band and within the television audio band Transmit at least two additional audio signals simultaneously with at least one center frequency, wherein at least one said center frequency is equal to two additional audio signals of said at least one center frequency in transmission. Five or video program signals and do not interfere by an amount that does not exceed the limit around the TV frequency band characterized by the step of transmitting to be displaced from the normal audio center frequency is how operation of the television system. 2. A method according to claim 1, wherein the plurality of audio program signals are transmitted at center frequencies displaced from each other by an amount not interfering with each other in the transmission. 3. The method of claim 2, wherein said at least two additional audio signals are transmitted by modulating in-phase and quadrature components of a carrier signal having at least one center frequency into these additional audio signals. 5. The method of claim 4, wherein the in-phase component of the carrier signal is modulated with one of the additional audio signals and at the same time a quadrature component is modulated with another of the additional audio signals and another of the additional audio signals modulates the in-phase component of the carrier signal And the at least two additional audio signals are scrambled by inverting the modulated signal periodically so that vice versa. 6. A method according to claim 2 or 3 or 4 or 5, receiving a regular television audio signal band and detecting a television audio program signal: receiving a regular television audio band and detecting a television audio program signal and two additional audio signals Selecting one of the television audio program signal or one of the two additional audio signals to produce voice; and selecting one of the three audio signals simultaneously with generating a television indication in response to the detected television video program signal. Producing a voice in response to one of the methods of operating a television system. Method according to claim 1 or 2 or 3 or 4 or 5, characterized in that the plurality of television audio programs are each in a separate language. The transmission step according to claim 1 or 2, wherein the transmitting step comprises the steps of: transmitting a video program signal at a first frequency; Transmitting one of the plurality of audio signals and then the other in the second frequency band as the first type: one of the audio signals is transmitted at a time interval of the second type while the other is of a length equivalent to the first type. Transmitting said one of the audio signals into said second frequency band in a second type that can be distinguished from said first type and thereafter in said order of time intervals transmitted at chronological intervals and vice versa. Portions of one and the other audio signals that are not transmitted in the first type are transmitted in the second type so that the two audio signals are transmitted in their entirety at the second frequency. Some of the portion of type 1 is a method for a television system comprising the step of sending the second type operation. Method according to one of the preceding claims, characterized in that the television video signal is scrambled. In-phase components of at least one carrier signal in response to one of the plurality of input signals and the next to the other in a sequence of time intervals such that one, but not all, of the input signals are conveyed to the in-phase component. Modulating: said part of said one and the other but not all of said input signals are carried by a quadrature component and said in-order in said order of time intervals such that in-phase and quadrature components carry all of said two input signals together Modulating a quadrature component of the at least one carrier signal in response to the one and the next one of a plurality of input signals; and combining the modulated in-phase and quadrature components for transmission. A plurality of input signal scramble methods for secure transmission characterized. The scramble method according to claim 10, wherein the order of the time intervals includes time intervals in which the duration changes in a predetermined pseudo-random manner. 12. The method of claim 10 or 11, wherein the input signals are both information signals and one information signal is an audio signal combined with a television video program. 12. The method according to claim 10 or 11, wherein at least two input signals are provided and all of the input signals are audio program signals in combination with a television video program, wherein one of the audio program signals is of a first language and the other audio program signal is Scrambled method, characterized in that the second language. 11. The method of claim 10, wherein said one and the other of said input signals change to frequencies within the same frequency band and further modulate a second carrier signal with combined in-phase and quadrature components of said at least one carrier. And transmit the modulated second carrier. 11. The method of claim 10, further comprising: demodulating a modulated in-phase and quadrature component of a carrier signal, comprising: demodulating a portion of a demodulated in-phase component including the one input signal as a first output signal and the other input signal; Providing a portion including a second output signal: a portion of a demodulated quadrature component including the one input signal as the first output signal and the other input signal as the second output signal And descrambling one or the other of the input signals by providing a portion of the input signal. 11. The method of claim 10, further comprising: demodulating in-phase and quadrature components of a carrier signal; One of the plurality of input signals comprising the in-phase and quadrature components of the carrier signal by alternatingly applying the demodulated in-phase component and the demodulated quadrature component of the carrier signal to the output terminal in the order of the time interval And a scrambled unscrambled one. 17. The method of claim 15 or 16, wherein the order of the time intervals is characterized by the fact that the time intervals vary in duration in a predetermined pseudo-random manner. 17. The method of claim 15 or 16, wherein said one and the other of the input signals are both information signals and one information signal is an audio program signal in combination with a television video program. 17. The apparatus according to claim 15 or 16, wherein said one and the other of said input signals are both audio program signals in combination with a television video program, wherein one audio program signal is in a first language and the other audio program signal is in a second. Scramble method, characterized in that the language. 17. The method of claim 15 or 16, further comprising: modulating a second carrier signal with both modulated in-phase and quadrature components of at least one carrier, wherein the one and the other of the input signals are varied at frequencies within approximately the same frequency band; And transmitting the modulated second carrier. A television transmitter for transmitting said television video program signal and said plurality of television audio program signals, each combined with said video program signal, within said single television channel bandwidth; And a receiving device which receives the transmitted television video program signal and the plurality of television audio program signals, selects any one of the plurality of audio program signals together with the television video program signal, and generates a television video display and an auxiliary voice. Apparatus for implementing the method of claim 1, wherein 22. The method according to claim 21, wherein the audio program signal and the video program signal are for transmitting the television audio program signal and the video program signal in respective normal television audio signal frequency bands and video frequencies of all television frequency bands assigned to a single television channel. A device to be transmitted at a normal audio center frequency and a video center frequency assigned to normal transmission of respective audio signals and video signals in the normal television audio frequency band and the video frequency band, and at least in the television audio frequency band in the whole television frequency band; For simultaneously transmitting at least two additional audio signals at one center frequency, the at least one center frequency being transmitted by two audio signals at the at least one center frequency And a simultaneous transmitting device which is displaced from the normal audio center frequency by an amount that does not interfere with the vision audio program signal or the video program signal and does not exceed the limit of all television frequency bands. 23. The apparatus of claim 22, wherein the apparatus for transmitting the two additional audio signals simultaneously has an apparatus for modulating in-phase and quadrature components of a carrier signal having at least one center frequency with additional audio signals. . 24. The apparatus of claim 23, wherein the apparatus for transmitting the two additional audio signals simultaneously modulates the in-phase component of the carrier with one of the additional audio signals while simultaneously modulating the quadrature phase component with another audio signal of the additional audio signals. And a device for periodically inverting the modulated signal such that another of the additional audio signals modulates the in-phase component of the carrier signal and vice versa. 25. An apparatus according to claim 22 or 23 or 24, for receiving a television video program frequency band and detecting a television video program signal, said apparatus for receiving a television television program frequency band and detecting a television audio program signal and two additional audio signals: A device for selecting a television audio signal or one of two additional audio signals for speech production: and responding to a selected one of the three audio signals simultaneously while producing a television representation in response to the selected television video program. Characterized by having a device for generating speech. 27. The apparatus of claim 25, wherein the regular television audio program signal is in one language and at least one of the additional audio signals is in another language and each language is a soundtrack in combination with the television video program signal. A first and second signal source for at least two different audio signals and a third signal source for at least one television video program signal: a first transmitting device for transmitting a video program signal of a first frequency band: two respective audios A second transmission in which one of the audio signals and then another signal are transmitted to the first type in the second frequency band in a sequence of time intervals such that a portion other than the signal is transmitted to the first type in the second frequency band. The audio signal in said sequence of time intervals such that one of the audio signals is transmitted at a time interval of type 2 while the other signal is transmitted at a time interval corresponding to the length of type 1 and vice versa. And a device for transmitting one of the following signals and then the other signal in the second frequency band in a second type that can be distinguished from the first type. Since one part of the audio signal and one part which are not transmitted to the first type are transmitted to the second type, the two audio signals are respectively transmitted at the second frequency as a whole, but some are transmitted to the first type and some to the second type. A television audio and video program signal transmission system according to the method of claim 1, characterized by having the second transmission device. 28. The apparatus of claim 27, wherein the second transmitter generates an in-phase component and a quadrature component of the first carrier signal: modulating the in-phase component with the one signal and the other signal of the audio signals, thereby generating the first component. A device for generating a type, and a device for generating a second type that can be distinguished from the first type by modulating a quadrature component with the one and the other of the audio signals. 29. The apparatus of claim 28, further comprising a device for combining a modulated in-phase component and a quadrature component of the first carrier signal, wherein the device has a device for modulating a second carrier signal with the combined components from the combination device. 30. The system of claim 27 or 28 or 29, characterized by an apparatus for generating the order of time intervals such that the time intervals vary in duration in a pseudorandom manner.

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