KR850001716B1 - Cable television system - Google Patents

Abstract

Receiver of wire-TV that uses a two-way transfer method on the wire- broadcasting network and sends nessary information to the transmitter. The function of a two-way transfer control system for CATV is immediate transfer of information from the receiver of CATV to the broadcasting station. Though one transfer cable is connected between the broadcasting station and the receiver, the two way transfer control system for CATV is supplied by one transfer cable.

Description

Mutual transmission control system for CATV

1 is a schematic circuit diagram of a conventional CATV system.

2A and 2B are schematic circuit diagrams of a CATV inter-transmission control system according to the present invention.

3A and 3B are schematic circuit diagrams of a data transmitting and receiving device in FIG. 2;

4A and 4B are a schematic diagram and a circuit diagram of a converter in the second diagram.

5 is a time waveform diagram of an operation time and a data output of a data transceiver on the wire broadcasting station side.

The present invention relates to a mutual transmission control system for CATV, and in particular, to transmit the necessary information from the user side of the receiver of the wired TV to the broadcasting station side of the receiver using the data bidirectional transmission method to the cable broadcasting network using the coaxial cable and the feeder line. The present invention relates to a CATV inter-transmission control system capable of providing information and video services to the sender at the same time.

In the conventional CATV system, the video service is unilaterally transmitted from the broadcasting station to the receiver side. Therefore, the intention or information of the receiver side could not be transmitted to the broadcasting station through the CATV. Therefore, there was an inconvenience in that the receiver side made a phone call separately.

In addition, all information may be provided to the receiver, but the response may not be immediately received by the broadcasting station. Therefore, all information processing may be determined by a one-step process or reconsideration that a telephone or other means of communication should be used. This causes a delay in the process of the step. In the end, everything goes counter to the present times when things must be handled and sorted out quickly and accurately. It is therefore an object of the present invention to provide a CATV inter-transmission control system in which CATV receivers can view or hear broadcast information and immediately transmit a decision to a broadcast station.

Another object of the present invention is to provide a CATV control system capable of mutual information transmission even if only one transmission cable for CATV is installed between a broadcasting station and a receiver.

According to the present invention, there is provided a mutual transmission control system for CATV, which is also suitable for market research, public opinion survey, and educational broadcasting.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 shows a schematic circuit diagram of a conventional CATV system. The part enclosed by the dotted line A becomes the broadcasting station side.

Here, the image reproducing apparatus 1 is shown as a video tape player in this drawing, but may also be a video disc player, and may be an apparatus 2 for providing an information image in some cases. The image mixer 3 mixes a plurality of image outputs Vo from the plurality of image reproducing apparatuses 1 and the information image providing apparatus 2 and supplies them to the transmission amplifier 4. An output terminal of the transmission amplifier 4 is connected with a video monitor 5 for monitoring the output state of the broadcasting station and a coaxial cable 6 connecting the broadcasting station and the receiver.

In addition, the part enclosed by the dotted line B becomes a receiver side. Here, the video output is supplied to the receiver 8 of the receiver via the distributor 7. The reason for connecting the distributor 7 to the coaxial cable side is to prevent the noise generated by the receiver 8 from being transmitted to the other receiver 8. As a result, according to such existing facilities, intercommunication or mutual transmission is impossible, and only signal transmission from the broadcast station A to the receiver B is possible.

2A and 2B show a schematic configuration diagram of the entire system according to the present invention. Here, the portion surrounded by the dotted line C becomes a broadcasting station, and the portion surrounded by the dotted line D becomes the receiver side. Looking at the broadcasting station side, in addition to the apparatus shown in FIG. 1, a computer 9 is connected to the output terminal of the transmission amplifier 4 and a data transceiver 10 is also connected.

The data transceiver 10 is connected to the bidirectional amplifier 11 on the receiver side D, and the bidirectional amplifier 11 is connected to the bidirectional divider 12 via a coaxial cable 6. The bi-directional distributor 12 on the receiver side is connected to the bi-directional divider 13, and the bi-directional divider 13 is connected to the transducer 14. The transducer 14 is also connected to a receiver 8 for the receiver.

Here, those indicated by the display numbers 1 to 5 are the same as those of the conventional CATV system. The computer 9 is composed of a main keyboard portion, a disk memory portion and a printing portion, and a monitor portion. The functions of the computer 9 record data on the receiver side and peripheral devices connected to the computer 9 according to the requirements of the receiver side. (21 ~ 24) will be activated. The data transceiver 10 plays a role of transmitting data at the computer 9 and of receiving data at the receiver side.

The configuration is similar to that of FIG. 3 and the description thereof will be given in FIG. The bidirectional amplifier 11 compensates for the amount of attenuation of the data output signal from the data transmitter 10 in the coaxial cable 6. The bidirectional amplifier 11 also compensates for the amount of data output signal of the converter 14 on the receiver side being audited in the coaxial cable 6. The bidirectional splitter 12 transmits the signal of the cable 6 example to the bidirectional splitter 13 and simultaneously transmits the data signal on the bidirectional splitter side to the cable 6.

However, this bidirectional transmission was mutual interference. The reason for this is that the output data signal from the transmitter of the data transceiver 10 is converted into a frequency band and transmitted in a specific frequency band, for example, 100 to 150 MHz. The data frequency / voltage conversion signal of the frequency band is mixed with the video signals 62MHZ to 250MHZ and transmitted to the bidirectional branching unit 13.

This frequency band is selected as the frequency between the low channel and the high channel of the existing television signal. That is, the transmission frequency band of the data transceiver 10 is 100-150 MHZ. This mixed signal is applied to the transducer 14 via the bidirectional branch 13. The converter 14 will be described in detail with reference to FIGS. 4A and 4B. In the converter 14, a data receiver 18 and a data transmitter 19 are provided. The data frequency voltage conversion signal at the data transceiver 10 is applied to the data receiver 18 in the converter 14.

Of course, the data receiver 18 is tuned to the frequency band of the data transmission signal. When the receiver 18 is operated by the data frequency voltage conversion signal, the data transmitter 19 is operated accordingly. As the transmitter 19 is operated, information signals for the sensing control unit 17 and the international language unit 16 are transmitted to the computer 9. The transmission frequency at this time is, for example, 10 MHZ to 50 MHZ. Therefore, the receiver may operate the keyboard of the international language fishery unit 16 to request the desired information to the cable broadcasting station, or to select the channel of the cable broadcasting station to watch the receiver 8.

Two views of FIGS. 3A and 3B are shown. In FIG. 3A, the data receiver of the frequency shift conversion is shown, and in FIG. 3B, the transmitter of frequency generation is shown. Referring first to Fig. 3 (a), the transistors Q₁ and Q₂ act as collector ground amplifiers to receive a radio frequency input (10 MHZ) and consist of a capacitor (C₂) and a diode (D₁, D₂). A frequency / power conversion signal is output by the transistor Q3 across the power conversion unit.

These data outputs will be in the 100-150 MHz band, for example. Referring to FIG. 3b, a data transmitter is shown. For example, the oscillation circuit of the 10-50 MHZ frequency band is composed of a crystal oscillator 25 and a transistor Q _{4. At} this frequency, the one-side input (MOD) of the TTL (Q ₅ ) is applied. ) by modulating the necessary information is on is transmitted to the transistor (Q ₆₎ and the coil (L₁) constructed as a transmission amplifier.

As a result, the data transceiver of FIG. 3 converts a data signal required as a frequency / voltage converter to be transmitted to a receiver or to receive information at a receiver. In this way, a frequency / power signal separate from the image frequency is formed, thereby avoiding mutual interference.

Referring now to FIG. 4, a block diagram of the transducer is shown in FIG. 4a. In this case, the high frequency frequency portion of the signal input to the input terminal 26 is selected through the high pass filter 27 and applied to the divider 29. The distributor 29 distributes the input signal to the television cable broadcasting selection tuning switch 30, the channel selecting unit 31 of the cable broadcasting, and the information receiving unit 35 for receiving information from the cable broadcasting station. In addition, the output of the low channel frequency from the response transmitter 36 is applied to the input terminal 26 to the input terminal 26 through the low pass filter 28.

However, this signal cannot be passed by the high pass filter 27 to the output terminal 37. The response transmitter 36 is also connected to the information receiver 35 so that the information receiver 35 is not operated during the period of receiving the information from the cable broadcasting station. Therefore, the operation period of the response transmitter 36 does not overlap with the time during which the transmitter of the data transceiver 10 on the wire broadcasting station side operates. This means that only one transmitter transmits because transmission and reception are simultaneously performed through the same line (cable).

FIG. 4B is a circuit diagram showing the block diagram of FIG. 4 in detail. Since the function here has been described in FIG. 4A, further description will be omitted. In FIG. 5, the operating time of the data transceiver on the wire broadcasting station side and the time waveform of the data output are shown.

FIG. 5A is a data output waveform of the data transceiver 10 at the cable broadcasting station side, and FIG. 5B is a data output waveform of the data transmitter 19 in the converter 14. FIG. FIG. 5C is the operating time of the transmitter of the data transceiver 10 and FIG. 5D is the operating time of the data transmitter 19. FIG. 5e shows the operating time of the receiver of the data transceiver 10 and the data receiver 18. FIG. In the example of FIG. 5A, the period t₁ represents the time zone of the flag signal, the period t2 is the time zone of the designated address call signal, and the period t₃ is the time zone of the control signal and the state check signal of the apparatus.

As described above, the present invention enables not only mutual information exchange but also mutual control.

Claims (5)

In the CATV system, the cable broadcasting station side C is provided with a computer 9, and a data transceiver 10 for frequency-to-transforming output signals from the computer, and the receiver side D and a bidirectional amplifier 11 are bidirectional. A transmission system for CATV, in which a distributor (12), a two-way branch (13), and a converter (14) are installed, and a wire broadcasting station and a receiver are connected by coaxial cable (6). 2. The inter-transmission control system for CATV according to claim 1, wherein the data transceiver (10) is made up of a data transmitter representing an output of a frequency band which is a television channel frequency idle and a data receiver synchronous with a signal in a low frequency band. The CATV according to claim 1, characterized in that the converter (14) consists of a television channel frequency tuning section (15), an international language control section (16), a sensing control section (17), a data receiver (18) and a data transmitter (19). Interworking system. 4. The inter-transmission system for CATV according to claim 3, wherein when the data receiver (18) in the converter (14) tunes to a frequency band which is a television channel frequency idle, the transmitter (19) shows output of a low frequency band. 4. The transmission system according to claim 3, wherein the computer (9) records the response output from the converter (14) to operate the peripherals (21-24).

Images