JPS637506B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-way CATV system in which individual video data signals can be transmitted to each terminal device using transmission of a polling data channel.

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. The present invention provides a CATV system that allows each terminal device to display individual video data on a television receiver, receive individual video data from each terminal device, and manipulate the video data by operating each control section. be.

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 source group 14 includes a video disc player 16,
There are 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 signal is demodulated once by the demodulator 15 and output to the modulation transmitter 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, a data modulation transmitter 30, a data A processing section 31 and a data storage section 32 are provided, and the data modulation sending section 30 is connected to the data processing section 31, and the data processing section 31 is connected to the 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 branch/divider 36 in the CATV video processing section 34, and a converter 37 and a modulation/demodulation section 38 are connected to the branch 36, respectively.
The output of 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, the video data processing unit 35 houses an interface 41 for receiving video data signals and a data terminal controller 42 to improve the reliability of data transmission. The interface 41 and data terminal controller 42 are also connected to each other. The video data from the data terminal controller 42 is transmitted to be temporarily stored in the video data storage section 43, and the data for one screen from the data terminal controller 42 is transmitted to the video RAM 4.
The output of this video RAM 44 is connected to a switch circuit 40. In addition, the data terminal controller 42 also connects the switch circuit 4
A signal for switching 0 is transmitted to the switch circuit 40, and the output of the switch circuit 40 is connected to the television receiver 11. Furthermore, an operation box 45 is connected to the data terminal controller 42 as a control section that outputs control signals for processing the video data stored in the video data storage section 43.

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 and control box 12 are connected to the main box 1 by a cable 50.
0, control box 12,
The operation box 45 is placed near the television receiver 11. The control box 12 has a flat box shape, and on its surface is provided a rectangular channel table 46 separated by a large number of matrices.
Surrounding this channel table 46 are a channel selection button 47, a group selection button 48, and a response/individual data specification button 49 on the left, right, and bottom sides.
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/individual data designation button 49 is used as a response button when a viewer participation program is broadcast using a television line, and one of the
For example, by pressing (f), a video data command is sent to the center 1, and the button is switched to communication of individual video data and is used as an individual data designation button.
Depending on the next button you press, for example (a) is the weather forecast, (b)
(c) is the stock market, and (c) is the video game.
It corresponds to various information specific to the area where the CATV system is installed.

In addition, the main box 10 and the operation box 45
and are connected by a cable 51. A lever 52 and a dial 53 are provided on the top surface of the operation box 45.
3 to operate the television.

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. Therefore, the logic controller 39
outputs a control signal to the converter 37, which converts the frequency of the selected channel to the frequency of a specific channel (for example, the second channel) being received on television. When the above-mentioned polling is performed, the calling signal of the polling is input from the branching device 36 to the modulation/demodulation section 38, and if the address number matches the calling signal, the logic controller 39 receives a data signal in response via the modulation/demodulation section 38. (For example, which channel is being received and how is it responding?). This data signal is sent to the branch cable 9 by the branch 36.
It is transmitted to the transceiver 25 via the trunk cable 3. At this time, the switch circuit 40 is in the state shown in FIG. 2, and the data terminal controller 42 is inactivated by the logic controller 39 via the interface 41. Next, a case where individual video data signals are received by the television receiver 11 in each home will be described.

(b) When playing a video game When (c) of the response/individual data specification button 49 of the control box 12 is pressed, the logic controller 39 in the main box 10 uses this signal to control the CATV video reception operation by the converter 37. At the same time, the data terminal controller 42 is set to a standby state. In this state, if there is polling from the center 1, the modulation/demodulation section 38 sends out an instruction from the logic controller 39, and the main box 10
sends a command indicating that it is requesting individual data. 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. Data processing section 3
1, in response to this, the video data of the video data list is first retrieved from the data storage section 32, modulated by the data modulation sending section 30, and sent to the main box 10 requesting the polling channel during the free polling time. Send using Although this data signal is a video, it is digitally encoded and cannot be reproduced as is on a television receiver. The video data signal transmitted to the main box 10 is sent to the branch 3.
6, modem section 38, logic controller 3
9. The data is transmitted to the data terminal controller 42 via the interface 41 and temporarily stored in the video storage section 43. At this time, the switch circuit 40 is switched to the lower side using the data in FIG.
The image of the video data list stored in the video data storage section 43 is converted by the data terminal controller 42 so that it can be operated by the television receiver 11 and stored in the video RAM 44, and the image is displayed on the television receiver 11. It can be done. This video data list is shown in FIG. When the individual program list shown in FIG. 4 is displayed, one of the video games is selected from the list and the designation is transmitted using the response/individual data designation button 49. That is, by selecting and pressing (c) of the response/individual data designation button 49, the data signal is transmitted from the main box 10 to the center 1 in the same manner as described above, and the program corresponding to the designated signal is stored in the data storage section. 32 and sent to the main box 10 by the data modulation sending section 30. The sent video game program corresponding to (c) is stored in the video data storage section 43 via the modulation/demodulation section 38, logic controller 39, interface 41, and data terminal controller 42. This video data storage unit 4
The program stored in the computer 3 transmits the video data of the image from the data terminal controller 42 to the video RAM 44, and causes the video RAM 44 to display the video game image on the television receiver 11. When operating this television game to change the screen of the television receiver 11, the operator transmits the operation signal to the data terminal controller 42 by operating the lever 52 or dial 53. The data terminal controller 42 processes the operation signal using a program in the video data storage section 43, transmits how the next image will be displayed as video data to the video RAM 44, and displays it on the television receiver 11. . By performing a series of these operations, you can enjoy the video game. In addition,
If the program to be stored is long and cannot be transmitted in its entirety within one data communication time, it may be divided into several parts and stored in the video data storage section 43.

(b) When viewing the weather forecast.

If you want to view the weather forecast from the separate program list in FIG. 4, after displaying this program list, press (a) of the response/separate data designation button 47 of the control box 12, and this signal will display the weather forecast in the main box. The logic controller 39 in the main box 10 sets the interface 41 in a standby state, and when there is polling from the center 1 in this state, the modem unit 38 sends out a command from the logic controller 39, and the main box 10 Send a command requesting individual weather forecast data in (a). The center 1 receives this command with the data transmitter/receiver 25, and the computer 26 makes a judgment and calls the data processing section 31. In response to this, the data processing unit 31 retrieves the weather forecast video data corresponding to (a) from the data storage unit 32, and the data modulation sending unit 30
The requesting terminal device 2 modulates the
The data is sent to the main box 10 of No. 8 using the polling channel during polling free time. The video data signal transmitted to the main box 10 is temporarily stored in the video data storage section 43 in the same manner as described above, and is sent to the television receiver 11 through the video RAM 44 for reproduction. The video data signals sent from this center 1 are weather forecasts for various parts of Japan, as shown in Figure 5.
The information is extremely rough. Furthermore, if you want to know detailed weather forecasts, you can select the area you need from the list in Figure 5 and get detailed information. For example, if you want to know the weather forecast for each city in the Kanto region, press (c) of the response/separate data specification button 47 and send a command to the center 1 during the next polling as described above. . The center 1 selects and extracts information corresponding to the command from the data storage section 32, sends it toward the main box 10, converts it using the data terminal controller 42, and transmits the video data signal to the video data storage section 43. The video data signal shown in FIG. 5 is erased, a new video data signal is stored, and the stored video data signal is transmitted to the television receiver 1 via the video RAM
Tell 1. A screen with this new video data signal is shown in FIG. In this manner, the center 1 can sequentially transmit requested data in response to commands from the main box 10.

(c) When looking at stock market conditions.

If you want to view stock market conditions from the separate program list in Figure 4, press button (f) to display the program list, and then press (b) of the response/separate data specification button 49 in the control box 12. A command requesting individual data on stock market conditions is sent to center 1. center 1
receives this command at the transceiver 25, the computer 26 makes a judgment and calls the data processing unit 31, retrieves all the video data of the stock market from the data storage unit 32, modulates it with the data modulation and transmission unit 30, and sends the request. The data is sent to the main box 10, which is currently running, using the polling channel during polling free time. The video data signal transmitted to the main box 10 is sent to the branch 3.
6, modem section 38, logic controller 3
9. All video data signals related to stock market conditions are transmitted to the data terminal controller 42 via the interface 41 and stored in the video data storage section 43. The video data signals regarding stock market conditions are numbered and stored in order in numerical order, and the first video data signal is a list of data stored in the video data storage section 43, and this list is The video data signal of the list is temporarily transmitted to the video RAM 44, and the video data signal of the list is transmitted from the video RAM 44 to the television receiver 11 via the switch circuit 40. This list of video data signals is shown in FIG. You can select the information you want to know from this list, for example,
(6) If you want to see information about electricity and services, press the corresponding button (f) of the response/separate data specification button 49, and
9 to that effect. logic controller 3
At step 9, the fact that the command has been received is transmitted to the data terminal controller 42 via the interface 41, and the data terminal controller 4
2 selects information regarding electricity and services from the video data signal stored in the video data storage section 43 (6), and converts the video data signal into a video data signal.
The information is stored in the RAM 44 and displayed on the television receiver 11. A screen based on this video data signal is shown in FIG. By repeating this operation, the information stored in the video data storage section 43 can be selected and displayed according to the command.

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 send out a 1 kilobit data signal is about 0.1 seconds, and the video data signal required to send out one still image is about 0.05 kilobit, so a large amount of video data signal can be transmitted in the free time mentioned above. can be sent. Terminal devices 28 in each of 60,000 households 2
Even if all receive this video data signal,
It 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, the data signals can actually be sent out in a shorter amount of time.

Various methods can be considered 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, respectively.

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 group 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 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, and m-1th terminal devices 28 issue commands, and after polling ends, they sequentially send 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.

(b) The video data signal is configured to receive a single still image, but it is also possible to display a moving image with a small number of frames by continuously changing the image every fraction of a second. In this case, several frames of video are stored in the video data storage unit 43 in the video data reception storage unit 35 with one data signal, and the video is sequentially retrieved one frame at a time, and when receiving each video data signal, an empty frame is stored. If the data is stored in such a way that it fills up the access memory, moving images can be received continuously.

(b) If the video data signal from the center 1 is long, it can be divided into two or three times and sent and written every polling.

(c) 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.

Since the present invention is configured as described above, it is possible to transmit video data signals during polling idle time by using data lines without using TV program channels, and to transmit video data signals on the same frequency without using a specific TV channel exclusively. Using this, you can receive different information on each terminal device. Each terminal device can individually process the sent video data and perform various operations. Moreover, when video games are used with video data, the center prepares new games, which has the advantage that each household can enjoy fresh games every day.

[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 of the same terminal device, FIGS. 4 to 8 are explanatory diagrams showing the operation of this embodiment, and FIG. It is an explanatory view showing a data signal sending method same as the above. 1... Center, 10... Main box, 2
8...Terminal device, 31...Data storage unit, 32...
...Data processing section, 43...Video data storage section, 4
5...Operation box as a control unit.

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 an operation box that instructs the screen of the video data to be received by the television receiver. , a screen data storage unit that temporarily stores screen data of video data to be received by a television receiver, an interface that receives video data sent from the center, and a screen data storage unit that sends video data commands to the center and receives data sent from the center. The received video data is received via the interface, stored in the video data storage section, and the specific stored video data is called in response to the operation instruction from the operation box to perform screen operations and display the operation screen. and a video data processing unit that causes a television receiver to receive the image via the screen data storage unit, and transmits and receives video data during polling idle time using a polling data channel.