JPS637505B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a CATV system that can transmit individual video data signals to each terminal device using data lines and equipment.

CATV systems generally transmit television programs from a center to terminal devices installed in each home, but with the development of two-way communication in recent years, the corresponding data is transmitted at the television signal frequency in response to commands from the terminal devices. A communication method has been developed in which the information is transmitted from a center to a terminal device and reproduced on a specific channel in the same manner as other television broadcasts. However, the number of data transmission services corresponds to the number of TV channels that the center has, and there is a drawback that a specific TV channel must be used exclusively, which reduces the number of regular TV programs. It was hot.

In view of the above-mentioned drawbacks, the present invention utilizes polling idle time and the polling data channel to send a video data signal from a center to a terminal device, and the terminal device receives this video data signal separately from the television video signal. to be displayed on a television receiver,
Individual video data services can be provided for each terminal device, and the video data that can be stored on the terminal device is for multiple screens, and specific video data can be played back by determining the type of video data and operating it. The purpose is to provide a CATV system that can

Figure 1 shows the entire CATV system. This system consists of one center 1 and terminal devices 28 installed in tens of thousands of households 2, and the center 1 and the terminal devices 28 in each household 2 are connected by coaxial cables. A trunk cable 3 is drawn out from the center 1, and a trunk amplifier 4 is installed at a predetermined location on the trunk cable 3.
A turnout 5 is provided. A plurality of branch cables 6 are drawn out from this branch 5, and an extension amplifier 7 and a tap-off 8 are provided at predetermined locations on each branch cable 6. A plurality of branch cables 9 are pulled out from each tap-off 8, and the ends of each branch cable 9 are led into each home 2. The terminal device 28 in each home 2 is composed of a main box 10, a television receiver 11, and a control box 12.The end of the branch cable 9 is connected to the main box 10, and the television receiver 11 and control box 12 are connected to each other. It is connected to the main box 10. In other words, the center 1 and the terminal devices 28 of each home 2 are segmented and connected in a Christmas tree shape.

A receiving antenna 13 is erected outside the center 1, and the receiving antenna 13 is connected to a demodulator 15 in a source group 14. This base group 14 includes a video disc player 16, a video tape recorder 17, a studio 18, etc. The modulation sending unit 19 that receives signals from the source group 14 consists of two types of systems: one system includes an IF modulator circuit 20, a scramble circuit 21, and an up-converter circuit 22, and the other system includes an IF modulator circuit 23, and an up-converter circuit 24. The outputs of the up converter circuits 22 and 24 are connected to the trunk cable 3, respectively. Further, a data transmitter/receiver 25 for communicating with each main box 10 is connected to the trunk cable 3, and a computer 26 is connected to the data transmitter/receiver 25. A device 27 is connected.

Next, the operation of this CATV system will be explained.

A television receiver 11 is turned on, a control box 12 is operated while the television receiver 11 is fixed to a specific empty channel, and the main box 10 converts the frequency of the channel to be received into an empty channel and receives the image. The types of channels that can be selected in the control box 12 can be divided into (A) retransmission that receives TV radio waves as they are, (B) independent programs (free), and (C) paid programs, each of which allows you to select several channels. They have their own programs and have about 20 to 30 options.

(A) Retransmission The television waves received by the receiving antenna 13 are
The demodulated signal is once demodulated by the demodulator 15 and output to the modulation sending section 19. The IF modulator circuit 23 modulates the signal, and the up converter circuit 24 increases the modulated signal to a specific frequency. This modulated signal into a specific channel is transmitted through the main cable 3, the branch cable 6, and the branch cable 9, and is received by the television receiver 11.

(B) Independent programs Weather forecasts, news programs, etc., programs recorded by the video disc player 16 and video tape recorder 17, and live programs produced in the studio 18 are modulated by the IF modulator circuit 23 and the up converter circuit 24. At the same time, the signal is frequency-converted into a specific channel and transmitted to the trunk cable 3. This program is free of charge regardless of the number of times it is watched or the time, and each household 2 can watch it for a basic monthly fee.

(C) Paid programs New movies, specific programs, etc., such as video disc player 16, video tape recorder 1
7 and the live program produced in the studio 18 are modulated by the IF modulator circuit 20, and a specific synchronization signal is added to the image signal by the scrambling circuit 21, so that even if the image signal is received as it is, it will not turn out to be a normal image. It is processed so that it does not occur. Next, the up converter circuit 22 increases the frequency to the frequency of a specific channel.
Send to trunk cable 3. When each household 2 wants to receive this pay program, the signal sent in the main box 10 is demodulated into a normal image signal and transmitted to the television receiver 11, so that it can be viewed on a normal screen. When this pay program is received, a preset fee is calculated and the monthly basic usage fee plus the special usage fee is charged.

The center 1 and the terminal devices 28 of each home 2 are connected by a coaxial cable, but unless you know which home 2 is receiving which channel at a particular time, it is difficult to distinguish between paid programs and free programs. Therefore, the CATV system cannot be established. For this reason,
The data transmitter/receiver 25 outputs a search signal at regular intervals, and the main box 10 of each terminal device 28
is called to its main box 10 using an individual address number, and polling is performed to inquire which channel is being received during the search. Therefore, the main box 10 outputs a response indicating which channel is being received at that time, and sends it to the data transmitter/receiver 25. The data sent and received by the data transmitter/receiver 25 is organized and stored by a computer 26, and displayed or outputted by a peripheral device 27. Since this search is performed at regular intervals (every several to several tens of seconds), the audience rating, etc. can be summed up immediately.

Furthermore, some programs involve viewer participation, and viewers can operate the control box 12 to respond to questions in the program while watching the television receiver 11, and the response content (data) is sent to center 1 by a coaxial cable.

FIG. 2 shows a configuration for performing video data communication according to an embodiment of the present invention.Inside the center 1, in addition to a data transmitter/receiver 25, a computer 26, and a peripheral device 27, there is also a data modulation sending unit 30,
A data processing section 31 and a data storage section 32 are provided, and the data modulation sending section 30 is provided with a data processing section 31
The data processing section 31 is connected to a data storage section 32, respectively. The trunk cable 3 is provided with a mixer 33, and a data modulation sending section 30 is connected to the mixer 33. Further, control signals from the computer 26 are connected to the data processing section 31.

The main box 10 performs two-way data communication with the center 1 through a data line, frequency modulates the video signal from the center 1 into a specific channel, and transmits video data commands to the center 1.
The video data processing unit 35 is divided into a CATV video processing unit 34 and a video data processing unit 35. Branch cable 9
is connected to a branching device 36 in the CATV video processing section 34, a converter 37 and a modulation/demodulation section 38 are connected to the branching device 36, respectively, and the output of the converter 37 is connected to a switch circuit 40.
Inside the CATV video processing section 34 is a logic controller 3 connected to the control box 12.
This logic controller 39 is interconnected with a modulation/demodulation section 38 for bidirectional data communication, and the control signal of the logic controller 39 is transmitted to the converter 37. Next, a data terminal controller 41 for receiving a video data signal is housed in the video data processing section 35, and the data terminal controller 41 and the logic controller 39 are connected to each other. The video data from the data terminal controller 41 is stored in the video data storage section 42.
The video data for one screen is stored in the video RAM connected to the data terminal controller 41.
(random access memory) 43. In addition, the data terminal controller 4
1 is connected to a numeric keypad type keyboard 44. Furthermore, a signal for switching the switch circuit 40 is transmitted from the data terminal controller 41 to the switch circuit 40. Said video
The output of the RAM 43 is connected to the television receiver 11 via a switch circuit 40.

FIG. 3 shows the configuration of the terminal device 28, in which the main box 10 is fixed to a wall or the like in the room, and the television receiver 11, control box 12, and keyboard 44 are connected to the main box 10 by a cable 45. The control box 12 and keyboard 44 are placed near the television receiver 11. The control box 12 has a flat box shape, and its surface has a rectangular channel table 4 separated by numerous matrices.
6 are provided, and channel selection buttons 4 are provided on the left and right sides and the bottom side surrounding this channel table 46.
7. Group selection button 48 and response button 49
is provided. The channel selection button 47 and group selection button 48 each correspond to the channel table 4.
Their number and position are determined so that one corresponds to each row or column of 6, and the channel selection button 47
By pressing one of the and group selection buttons 48, the channels at the intersection of the channel table 46 can be selected. The response button 49 is used as a response button when a viewer participation program is being broadcast using a television channel. The command button 12 which becomes the keyboard 44 is a group of 10 push buttons 5 from 1 to 0.
0, and this push button group 50 is used as a button for specifying individual data.

Next, the operation of this embodiment will be explained.

As mentioned above, when receiving a television program sent from the modulation transmitter 19 of the center 1, press the channel selection button 4 of the control box 12.
7.Press the group selection button 48, select the channel to receive, and send the signal to main box 1.
Tell 0. For this reason, the logic controller 39
outputs a control signal to converter 37 to convert the frequency of the selected channel to the frequency of a specific channel (for example, the second channel). While this channel is selected, a specific signal for that channel is transmitted to the modulation/demodulation unit 38, and when the above-mentioned polling is performed, the calling signal for that polling is input from the brancher 36 to the modulation/demodulation unit 38, and the address If the number matches the calling signal, a response data signal (for example, which channel is being received and how the user is responding) is output. This data signal is sent to the transmitter/receiver 2 via the branch cable 9 and main cable 3 by the brancher 36.
5 will be informed. Note that, at this time, the data terminal controller 41 is kept inactive by the logic controller 39.

Next, a case where individual video data signals are received at each home will be explained.

When the first command button of the button group 50 on the keyboard 44 is pressed, this signal causes the logic controller 39 in the main box 10 to stop the CATV video reception operation by the converter 37, and also causes the data terminal controller 41 to stop the CATV video reception operation by the converter 37.
Set to standby state. If there is polling from the center 1 in this state, the modulation/demodulation section 38 sends out a command from the logic controller 39, and the main box 10 sends out a command indicating that it is requesting the individual data pressed on the keyboard 44. The center 1 receives this command with the transmitter/receiver 25, and the computer 26 makes a judgment and calls the data processing section 31. In response to this, the data processing section 31 takes out the video data for the video data list from the data storage section 32, and the data modulation sending section 30
It modulates the data and sends it to the requesting main box 10 using a polling channel during polling idle time. Although this data signal is video data, it is digitally encoded and cannot be reproduced as a video on the television receiver 11 as it is. The video data signal transmitted to the main box 10 is transmitted to the data terminal controller 41 via the brancher 36, the modulation/demodulation section 38, and the logic controller 39, and the digitized data signal is transmitted to the TV receiver 11 by the data terminal controller 41. It is converted so that it can be scanned and stored in the video data storage section 42.
When this video data signal is transmitted to the data terminal controller 41, the signal is transmitted to the switch circuit 40, and the switch circuit 40 is switched to display the video data.
Connect the RAM 43 and the television receiver 11.

The video data sent from the aforementioned center 1 is stored in the video data storage section 42. and,
The data terminal controller 41 transmits the stored video data as one screen to the video RAM 43, the video RAM 43 sends the one screen as a video data list to the television receiver 11, and the screen is played back on the television receiver 11. be done. In this video, the types of data are displayed as a list as shown in FIG. The video command is sent to the center 1 side from the modulation/demodulation section 38 via the data terminal controller 41 and logic controller 39. This command is received by the data transmitter/receiver 25, and the computer 26 makes a judgment and calls the data processing section 31. In response to this command, the data processing unit 31 calls out the video data corresponding to the selected code from the data storage unit 32, modulates it again using the data modulation sending unit 30, and sends the requesting terminal device 28 a free time for polling. Send using data line.
This sent video data is collected at once for several to several dozen screens for one selected code, and this video data is sent via the modulation/demodulation section 38, logic controller 39, and data terminal controller 41. The video data is stored in the video data storage unit 42, and only coarse data in the video data is stored in the video data storage unit 42.
The data is stored in the RAM 43, and only the rough initial data is displayed on the television receiver 11. here,
For example, if the image of the table of contents is shown in Figure 4, "1"
When the center 1 issues a command that requires video data of the weather forecast, the center 1 sends all information corresponding to the command "1" to the terminal device 28. The coarsest data of this "1" information is displayed as the weather forecast for the entire country as shown in FIG. Next, when the user wants to know detailed weather forecasts for various parts of the country, he inputs the number "3" for the Kanto region on the keyboard 44, and transmits the selection command to the data terminal controller 41. This data terminal controller 41 selects the video data corresponding to "3" from the video data stored in the video data storage section 42 and sends it to the video RAM 43 (the memory of the previous screen is erased). ” For example, the weather forecast for the Kanto region can be found in Part 6.
Display it as shown in the figure. This weather forecast can be selected at random from a plurality of images stored in the video data storage section 42, and can be freely selected regardless of the order of the storage codes. Figures 7 and 8 show display examples when stock market information is selected from the table of contents screen in Figure 4.
When the numerical value is entered on the keyboard, all video data of stock market conditions is sent from the center 1 to the terminal device 28. For this reason, a rough code regarding stock market conditions is first displayed as shown in FIG. 7, and detailed information can be obtained by commanding specific information from this code. For example, if it is information about electrical appliances or services with the number "6", inputting the number "6" into the keyboard 44 will generate video data, and the information corresponding to the "6" code will be selected from the video data in the storage unit 42. The display shown in FIG. 8 is displayed. If there is information corresponding to a code typed into the keyboard 44, the image corresponding to that code can be displayed any number of times. Next, a data communication method will be explained. The above-mentioned polling takes about 3 to 4 seconds even if one center 1 searches all the terminal devices 28 of tens of thousands of households 2. Therefore, if the polling cycle is set to every 10 seconds, there will be about 6 seconds of idle time, and video data can be sent using the polling data line (frequency) during this idle time. The time required to transmit a 1 kilobit data signal is approximately 0.1 seconds, and the video data signal required to transmit one still image is approximately 0.05 kilobit.
A large amount of video data signals can be transmitted in the above-mentioned free time. Terminal devices 2 in each of 60,000 households 2
Even if all 8 receive this video data signal, it only takes about 5 seconds to send out all the data signals, and since the same data signals may be sent out at the same time, it actually takes less time. Data signals can be transmitted in a short time.

Various methods are possible for transmitting the selected video data signal to each terminal device 28, and a specific example thereof is shown in FIG. In FIG. 9, the time flowing from left to right is represented by a straight line, and the upper side of the line shows the time during polling, and the lower side of the line shows the time during which the data signal is sent out.

In FIG. 9A, after polling the terminal device 28 of each household 2, a time period is set for transmitting the video data signal, and polling is performed at intervals. In this method, when polling each individual terminal device 28, if a command to send a video data signal from the terminal device 28 is detected, the video data signal is sent immediately after polling. In the figure, the n-1, n, n+2, n+
3. A video data signal is being sent to the n+6th household 2.

In FIG. 9B, a certain number of polls are grouped together, and after the polling for that group is completed, a video data signal is sent to only the terminal device 28 that received the command along with the address number of that terminal device 28. In the figure, the first, third, and fifth terminal devices 28 in the n-groove issue a command, and in response to this command, after the fifth terminal device 28 finishes polling, the first, third, and fifth terminal devices 28 A video data signal is sent to the terminal device 28.

In FIG. 9C, the terminal devices 28 of all households 2 connected to the center 1 are polled, and the terminal device 28 issuing the command is connected to the computer 26.
After polling of the terminal devices 28 is completed, the video data signal is sequentially sent out only to the terminal device 28 that generated the command stored in the computer 26 along with the address number of the terminal device 28. In the figure, the first, fourth, m-2, m-1
The th terminal device 28 is issuing a command, and after polling is completed, it sequentially sends out video data signals. This video data signal is sent out every time each polling ends, and the next polling starts immediately after the video data signal is sent out. Although both of the above embodiments are configured as described above, the configuration described below may also be used.

(a) If the video data signal from the center 1 is long, it can be divided into two or three times, sent out every polling, and written into the video storage section 42. Therefore, the capacity of the video storage section 42 can be made extremely large.

(b) The video data signal sent from the center 1 to the terminal device 28 must identify the individual terminal device 28 and send the video data signal according to the content of the command, and the address number must be followed by the video data signal. sending out a signal. However, if the receiving terminal device 28 can be identified by polling, for example in the case shown in FIG. 9A, only the video data signal can be sent without adding an address number.

(c) In the above embodiment, the keyboard 44 is provided separately from the control box 12 so that separate video data can be specified and controlled by operating the keyboard 44. However, the response button of the control box 12 49 can also be used as a button for specifying separate video data. In that case, one of the buttons 49, for example f, should be used as a video data request button, and when this button is pressed, video data for the table of contents shown in FIG. ,…
Each corresponds to, for example, weather forecast, shopping information, ticket reservation, etc., and data can be selected from coarse to fine data. Furthermore, if each subscriber registers the video data himself/herself at the center, it is possible to communicate the video data of, for example, each individual's address book and telephone directory.

Since the present invention is configured as described above, video data signals can be sent using a data channel for polling without using channels for television programs.
Each terminal device can receive different information using the same frequency without using a specific TV channel exclusively, and the terminal device can arbitrarily select video data as information with the necessary roughness. You can take it out.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the outline of the CATV system.
Fig. 2 is a block diagram showing an embodiment of the present invention, Fig. 3 is an external view showing the same terminal device, Figs. 4 to 6 are explanatory diagrams showing the operation of this embodiment, and Figs. FIG. 8 is an explanatory diagram showing the operation of another embodiment, and FIG.
The figure is an explanatory diagram showing the data signal sending method same as above. 1... Center, 28... Terminal device, 32...
Data storage section, 31... Data processing section, 35...
Video data processing section, 42...video data storage section.

Claims (1)

[Claims] 1. A cable connects the center and a large number of terminal devices, and television images are sent from the center to each terminal device, and two-way data communication including polling is performed between the center and each terminal device. The center side has a data storage section that stores multiple types of video data, and a system that reads video data specified by a video data command from a terminal device from the data storage section and sends it to the terminal device. The terminal device side includes a video data storage unit that collectively stores a plurality of video data sent from the center, and a screen selection unit that selects and instructs a screen of video data to be received by a television receiver. a keyboard, a screen data storage section that temporarily stores screen data of video data to be received by a television receiver, and a screen data storage section that sends video data commands to a center and sends a plurality of video data sent from the center to the video data storage section. and a video data processing unit that selects specific stored screen data and causes the television receiver to receive the data via the screen data storage unit according to a selection instruction from the screen selection keyboard, and polling data. A CATV system characterized by transmitting and receiving video data during polling idle time using channels.