JPH10164545A - Catv system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily construct a menu hierarchy or the like, without especially preparing a complicated function and to prevent restrictions in the case of expanding and adding functions by placing a WWW server in a center station, including a WWW browser in a terminal and performing the display of a menu and the execution of an application by using the WWW browser. SOLUTION: A WWW server 21 transfers data with a terminal 3 through an RF modem 22 (64QAM modulator and QPSK demodulator) for data communication control. In the meantime, the RF demodulator 38 (64QAM demodulator) for the data communication control of the terminal 3 demodulates outgoing signals from the RF modem 22 for the data communication control of the center station 1. Also, an RF modulator 39 (QPSK modulator) for the data communication control modulates incoming signals to the WWW server 21 outputted by a data communication control part 40. Further, the data communication control part 40 for controlling communication with the WWW server, and a system control part 37 for generally controlling the terminal 3 are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CATV system for displaying a menu and operating an application such as program selection from the menu, and a terminal thereof.

[0002]

2. Description of the Related Art Conventionally, when a menu is to be displayed on a CATV terminal, for example, an on-screen display (OSD) is provided as a menu display means inside the terminal, or a screen created by a personal computer or the like in a center station is TV-modulated and broadcast. However, this is defined as a menu channel, and when a menu display request is made on the terminal side, it is as if the terminal itself displays a menu by selecting the previously defined menu channel. There are two ways to make it appear.

[0003] For the OSD, a dedicated IC has been released.
The hardware configuration of the menu display system using the SDIC is, for example, as shown in FIG. O
In addition to the SD dedicated IC 302, a control microcomputer 301 and a font memory 30 for storing character conversion data
3. Memory 304 for further storing display screen data
Need. Here, the screen data is obtained by converting the characters to be displayed and the color of the background into special codes. When the menu is displayed, the microcomputer 301 uses the OSDIC3
02 is read from the memory 304 and sent to the OSDIC 302. I for OSD only
C302 displays screen data on a monitor while converting characters in the font memory 303 on the way. If the size of the memory 304 for storing the screen data is sufficient, the number of menus can be increased. In order to increase the menu hierarchy, it is necessary to create data called links that define the connection between menus. The data structure of the link between screen data must be recognized on the microcomputer that manages the screen data. Therefore, a special link recognition method is required.

FIG. 4 schematically shows an example of a link data structure for download for specifying the link structure. Syn indicating the type of packet to download
There is an area for storing the screen number to be currently displayed after the header section called "c", and data defining the operation of the terminal according to the option is input to the area behind the area. FIG.
In the case of, when a certain screen 3 is displayed, the choice is 4
4 (FIG. 4A). For example, if it is predetermined that these areas correspond to numbers 1 to 4 of the remote controller, when numeric key 1 is pressed, the data of area 1 is referred to and if data 01 is described, the screen is displayed. 1 is displayed (FIG. 4B).

If the data is 81, one channel is selected. The data described in the area is also defined. In this example, the value of the most significant bit identifies whether the display is a screen display or a channel selection. By linking them continuously, the link between the screens is completed. New functions can be added if the link data is devised. When another operation is added by an operation from the menu, for example, when a paid contract is to be made, the definition of the link data is redone. In other words, in the above example, since only two applications exist, that is, screen display and channel selection, data can be identified by one bit of the most significant bit. However, applications (kinds of operation) increase. At the same time, the number of bits required for the identification increases. In this example, since there are three applications, two bits are required for identification. Also, the microcomputer of the terminal needs to have a function of interpreting the new definition. This link data is downloaded from the center, and the terminal can perform a desired operation from a menu by storing and analyzing the data.

FIG. 5 shows a menu hierarchy image of a menu display method by the OSD. On the other hand, in a system in which the menu screen created by the center is TV-modulated and broadcast, a graphical screen display is possible as compared with the OSD.

FIG. 6 shows a simple system configuration diagram of this system. In addition to the broadcasting equipment 101 for performing retransmission and independent broadcasting of general terrestrial broadcasting and satellite broadcasting, the center station has a menu generation device 201 for creating and transmitting menus, and only a number of menus to be transmitted. TV modulator 203
(Assuming there are two channels up to 204), and each menu is transmitted to the terminal using another channel. In this method, the terminal realizes menu display by selecting a specific menu dedicated channel in response to a menu display request. For example, it is defined that the C39 channel is tuned when the menu button is pressed on the terminal. The operation of the application displayed on the menu is to respond to the special request only when the C39 channel is selected, as if the application item displayed on the menu operates only on the menu. Can be shown to do so. When the menu is hierarchized, the control based on the link data is used.

FIG. 7 shows an example of a download type link data structure corresponding to the above system. There is an area for storing a channel number to be currently selected after a header section called "sync" indicating the type of packet to be downloaded, and data defining the operation of the terminal according to the option is input to an area behind the area. In the case of FIG. 7, when a certain channel is displayed, it indicates that there are four options (FIG. 7A). For example, when it is predetermined that these areas correspond to the ten keys 1 to 4 of the remote controller, when the ten key 1 is pressed, the data of the area 1 is referred to, and when the data 0C40 is described, C40 is written. A channel is selected (FIG. 7B).
If there is no operational limitation or option when the channel is selected, the link data for the channel can be set to a free state by invalidating the link data (FIG. 7).
(C)).

FIG. 8 shows a menu hierarchy image diagram of a method of broadcasting a menu by TV modulation.

[0010]

However, the above OS
The method of displaying a menu using D is extremely inconvenient for a user who wants to differentiate, because the design and expression on the screen are limited by the performance and function of the OSDIC used. Further, as the number of menu layers increases, a memory area for storing menu data is required, hardware costs are increased, and a link structure is complicated, and maintenance becomes more difficult. Furthermore, when it is desired to add a new function, it may be necessary to rebuild from the link structure or, at worst, to change the microcomputer program of the terminal. On the other hand, in the method of broadcasting a menu using a certain frequency channel at the center station, increasing the menu hierarchy directly leads to the use of a new channel. Therefore, when considering the number and importance of available channels, video-on-demand However, there is a problem that the application itself in which layering is regarded as important becomes difficult to operate.

[0011]

In a CATV system according to the present invention, a WWW server is provided at a center station, and a WWW server is provided at a terminal.
The display of the menu and the execution of the application are performed using the WWW browser, including the W browser.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the CATV system according to the present invention will be described. FIG. 2 is a block diagram showing a configuration example of a system to which the present invention is applied. The center station 1 has a BS antenna 10 and a BS receiver 11 for receiving a BS satellite broadcast and demodulating a specific channel, and a television modulator 12 for each of the channels (m channels) for broadcasting.
The output is sent to the mixer 20. Further, it has a CS antenna 13, and has a CS receiver 14 for receiving CS satellite broadcasting and demodulating a specific channel, and a television modulator 15 for each broadcasting channel (n channels). Can be Furthermore, it has a normal terrestrial broadcasting antenna 16 and has a number of channels (p channels) for broadcasting a television signal processor 17 for converting television broadcast radio waves into cable television channel frequencies;
The output is sent to the mixer 20. Although it is considered that some broadcasting facilities of cable television stations include independent broadcasting facilities, a detailed description of the broadcasting facilities is omitted here because it is not important.

In addition to the above broadcasting equipment, there is a subscriber management device 18. The subscriber management device 18 controls and maintains the terminal 3 in the subscriber's home for each contract content of each subscriber, manages the viewing content, and bills the viewing fee. For communication with the subscriber terminal 3, a terminal control RF modem 19 (FSK modem)
Is used. Also, a WWW (World Wide Web) server 21
Having. The WWW server 21 stores data files constituting a menu screen and the like. The WWW server 21 is a data communication control RF modem 22 (64 QA
Data is exchanged with the terminal 3 through an M modulator and a QPSK demodulator.

On the other hand, the internal configuration of the terminal 3 distributes the signal transmitted through the cable television transmission line network 2 into a television signal, a terminal control signal, and a data communication control signal. R for signal and data communication control
A mixer / distributor 30 for mixing the signals of the F modulator 39, a tuner 31 for selecting an arbitrary TV frequency in accordance with a command from the system controller 37, and an N for demodulating the TV modulated signal.
A TSC demodulation unit 32, a graphic display control unit 34 that converts data from the system control unit 37 into an NTSC signal and outputs the same, and switches the output of the NTSC demodulation unit 32 and the output of the graphic display control unit 34 according to a command from the system control unit 37. A signal switching control unit 33, a terminal control RF demodulator 35 (FSK demodulator) for demodulating a downlink signal from the terminal control RF modem 19 of the center station 1, and a system control unit 3.
7, a terminal control RF modulator 36 (FSK modulator) that modulates an uplink signal output from the center station 1 to the center station 1, and a data communication control RF demodulates a downlink signal from the data communication control RF modem 22 of the center station 1. Demodulator 38 (64QAM
Demodulator), a data communication control RF modulator 39 (QPSK modulator) that modulates an uplink signal to the WWW server 21 output from the data communication control unit 40, and a data communication control unit 40 that controls communication with the WWW server. And a remote control light receiving unit 41 corresponding to the remote control operation of the subscriber, and an operation pad 4 for simplifying the operation with a browser instead of the remote control
The configuration includes a system control unit 37 that comprehensively controls the terminal 2 and the terminal 3. The system control unit 37 itself has a CPU and R
OM, RAM, etc.

Next, the operation of the embodiment on the operation on the WWW browser will be described. In the terminal, the browser screen is already displayed in the initial state. When a display of another menu is requested from the main screen by the remote controller or the operation pad 42. System control unit 3
7 (operation system) detects this and informs the data communication control unit 40 of the U
An RL (Universal Resource Locater) is transmitted to the WWW server 21 of the center station through the RF modulator 39 for data communication control. Here, the URL is a term that is routinely used to indicate the location of information on the Internet. For example, assume that the following URL is sent.

URL = http: //www.operater.co.jp/catv
/menu.html The meaning of this URL is to transfer the file menu.html in the directory / catv / of the server www.operater.co.jp using the protocol http (communication procedure). The URL arriving at the center station via the CATV network is the data communication control RF modem 22.
, And sent to the WWW server 21. The WWW server 21 sets the specified menu.html file to http
It is returned to the browser that made the request in the communication procedure. On the terminal browser, the transferred menu.html H
Titles and titles are displayed based on a text file described in the TML format. Also, the browser specifies a URL based on the description <IMG SRC = "image / menu.gif"> in the HTML file, and obtains an image file called menu.gif from the WWW server 21 of the center by HTTP. Then, the transferred image file is displayed at a predetermined position. In this way, a graphical menu can be displayed.

When the menu is hierarchized, the center station can easily create the hierarchies by describing the URL in an HTML file. As in the conventional case, link data is specially created and downloaded to the terminal. You don't have to.

Even when the number of display screens increases due to a more complicated hierarchical structure, the data sent to the terminal is always data for one screen, and the terminal itself needs to be provided with an amount of memory corresponding to the number of screens. There is no.

On the other hand, various services can be provided by incorporating a function corresponding to a special command into the browser. For example, a statement such as <CH "= 24"> is described in the HTML statement, and a function such as selecting a channel by selecting this statement is performed, so that all functions of the terminal are performed on the browser. Becomes possible.

When the channel is selected from the browser by the above method, the system control unit (operation system) 37 sends an instruction to the tuner 31 to tune a predetermined frequency. After the frequency tuning is completed, the tuner 31 returns a completion notification to the system control unit 37. At this timing, the system control unit 37 issues a signal to the signal switching control unit 33 from the display of the browser, which is the output of the graphic display control unit 34 selected so far, to the NTS.
The signal is switched to a TV signal output from the C demodulation unit 32. For example, when a pay program is viewed, the contents of the view are managed by the system control unit 37 and transmitted to the center station through the terminal control RF modulator 36 with the center station 1 using a predetermined communication procedure. The center station 1 receives the data demodulated by the terminal control RF modem 19 and performs data processing in the terminal management device 18. In this manner, the data communication by HTTP is performed for the operation of the terminal, and the CATV system having a comfortable operation environment can be constructed by using the communication control for the terminal control for the data relating to the maintenance and management of the terminal.

An embodiment of the CATV system according to the present invention will be described with reference to FIG. The configuration of the terminal is the same as that of the above-mentioned embodiment, but the configuration of the center station 1 is different from the configuration of the WWW server 21 and the following. After the WWW server 21 storing the data to be managed and updated by the center station, the information once accessed is stored, and when the same information is requested, the proxy server 26 which returns the stored information is returned.
Are installed in a plurality (27, 28). Each proxy server has a data communication control RF modem 23 (24,
25) are connected. In this system, a proxy server accessible to the terminal is determined according to the modulation frequency of the data communication control RF modulator 39 provided therein. It is now assumed that the terminals A and B access the same proxy server 26. First, terminal A has URL = http: // w
Suppose you access ww.operater.co.jp/catv/menu8.html. At this time, since the proxy server 26 does not have the URL information (menu8.html), the proxy server 26 accesses the URL again to acquire the information (menu8.html). In this case, most of the information should be obtained from the WWW server 21. The proxy server 26 temporarily stores the acquired information (menu8.html) internally, and then transfers this information to the terminal A.

Next, terminal B has the same URL = http: //www.ope
When accessing rater.co.jp/catv/menu8.html. At this time, since the URL information (menu8.html) is already stored in the proxy server 26, this information is directly transferred. As described above, for the second and subsequent accesses, there is an effect that the time saving effect is large and the access speed (speed until data is displayed on the terminal browser) is increased. Also, a plurality of proxy servers can update information in the proxy server by accessing a predetermined URL at regular intervals.
This means that the data in all the proxy servers is also updated within a certain period of time only by updating the file in the WWW server 21, and the maintenance and management of the data is facilitated.

An embodiment according to the sixth and seventh aspects of the present invention will be described with reference to FIG. Proxy server 26 (2
7 and 28), the data communication RF demodulator 43 and the data communication RF modulator 44 inside the terminal have a function of varying their respective frequencies within a predetermined range by a control signal from the system control unit 37. Have. For example, assume that the modulation frequency of the data communication control modem connected to the proxy server 26 is 240 MHz and the demodulation frequency is 75 MHz. At this time, if the number of accesses to the proxy server 26 detected by the center station exceeds a certain amount, the center station sends a terminal control RF modem 19 from the terminal management device 18.
, A data communication control frequency change signal (modulation frequency after change 81 MHz, demodulation frequency after change 246 MHz) is transmitted to any terminal. On the terminal side, R for terminal control
This signal is demodulated by the F demodulator 35 and decoded by the system control unit 37. The system control unit 37 includes a data communication control RF demodulator 43 and a data communication control RF demodulator 4.
4 is notified of the changed frequency. Since the data communication control RF demodulator 43 and the data communication control RF modulator 44 operate at the frequency designated and changed thereafter, the proxy server accessed by this terminal is different from the original proxy server 25. Thereafter, the amount of access is dispersed.

The overall operation is the same as that of the embodiment described so far, but the terminal control RF modem 19 connected to the terminal management device 18 of the center station is replaced with the WWW server 21 or the proxy server 23 (24, 25). The terminal is used in common with the data communication control modem 22 or 23 (24, 25) connected to the terminal control RF demodulator 35 and the data communication RF demodulator 38 or 43, and the terminal control RF demodulator 38 or 43 is used in the terminal. The modulator 36 may be shared with the data communication RF modulator 39 or 44. One embodiment according to the above invention is shown in FIGS.

As an embodiment utilizing the above invention, connection to the Internet can be considered. R for center station data communication
By connecting a router in parallel with the WWW server 21 before the F modem, a system including the Internet can be easily constructed. In addition, the homepage on the Internet can be browsed by the WWW browser on the terminal. In addition, it is possible to improve the access speed by devising the files in the WWW server 21 by using the JAVA language or the like, and it is added that such technology on the Internet can be easily applied.

Further, in the description of the present invention, a CATV system having analog broadcasting facilities is taken as an example, but it is apparent that the present invention can be applied to a digital system.

FIG. 14 shows a CAT having digital broadcasting equipment.
This is an example of a V system, and shows one embodiment of claims 12 and 13. In the center station, the CS digital satellite broadcast is once passed through the CS antenna 13 and the CS receiver 14 and then multiplexed in the multiplexer 50, and
And output to the mixer 20. On the other hand, the proxy server 26 (27, 28) connected to the WWW server 21 is connected to the terminal through the data communication control RF modem 23 (24, 25). Here, the data communication control RF modem 23 (24, 25) uses 64QAM modulation for modulation.

When viewing digital broadcasting at a terminal, the tuner 31 selects a frequency of the 64QAM modulator 51 of the center station. The output of the tuner 31 at this time is a modulated digital signal (MPEG2TS),
The signal is demodulated by an M demodulator 60, passed through an error correction means 61, a descrambling means 62 and a signal changeover switch 63, sent to a PSI acquisition means 64, and then decoded by an MPEG decoder 65 to be monitored through an NTSC demodulation unit. When a request to the WWW server is input from the remote controller or the operation pad 42, a command command to the WWW server is sent from the system control unit 37 to the data communication control unit 40. The data communication control unit 40 supports the http protocol and TCP / IP, and issues a file transfer request to the WWW server through the data communication control RF modulator 39. Here, the data communication control RF modulator 39 is QPSK.
It could be a modulator, but it could be a regular telephone modem. It is also conceivable to have an ISDN interface. In any case, the modulation method of the upstream signal is not a problem.

The system controller 37 outputs a request to the WWW 21 server and controls the system controller 37 so that the output of the signal changeover switch 63 is input to the data communication controller 40 inside the terminal. The tuning frequency of the tuner 31 is set to the modulation frequency of the 64QAM modulator specified or specified by any of the data communication control RF modems 23, 24, and 25. File data from the WWW server 21 or the proxy server 26 (27, 28) is
After 1, the signal is demodulated by the 64QAM demodulator 60. Thereafter, the output is sent to the data communication control unit 40 by the signal changeover switch 63 via the error correction means 61 and the descrambling means 62. The data received by the data communication control unit 40 is sent to the system control unit 37 and displayed on the browser.

[0030]

As described above, according to the present invention, it is possible to easily construct a menu hierarchy or the like without specially preparing complicated functions in the center station and the terminal. It is most suitable for systems where applications and menus are updated because there are almost no restrictions on the operation. In addition, it is possible to realize a graphical screen display on the terminal's WWW browser and execute the application with centralized operation It is.

[Brief description of the drawings]

FIG. 1 is a block diagram of a CATV system according to the present invention.

FIG. 2 is a system configuration block diagram showing an embodiment of the CATV system according to claim 4;

FIG. 3 is a block diagram showing a configuration of a menu display circuit using a conventional OSDIC.

FIG. 4 shows an example of a link data structure for realizing a conventional hierarchical menu structure.

FIG. 5 is an example of a hierarchical menu display by a conventional OSDIC

FIG. 6 is a block diagram of a conventional menu broadcasting system CATV system.

FIG. 7 shows an example of a link data structure for realizing a hierarchical menu structure of a conventional menu broadcasting system.

FIG. 8 shows an example of a hierarchical menu display by a conventional menu broadcasting method

FIG. 9 is a system configuration block diagram showing one embodiment of the CATV system according to claim 5;

FIG. 10 is a system configuration block diagram showing an embodiment of the invention according to claims 6 and 7;

FIG. 11 is a system configuration block diagram showing an embodiment of the CATV system according to claim 8;

FIG. 12 is a system configuration block diagram showing an embodiment of the CATV system according to claim 9;

FIG. 13 is a block diagram showing a system configuration according to an embodiment of the present invention.

FIG. 14 is a block diagram showing a system configuration according to an embodiment of the present invention.

[Explanation of symbols]

1: center station, 2: CATV network, 3: terminal, 10: BS
Antenna, 11: BS receiver, 12: TV modulator, 1
3: CS antenna, 14: CS receiver, 15: TV modulator, 17: TV signal processor, 18: Subscriber management device, 19: RF modem for terminal control, 20: Mixer, 21: WWW server, 22: RF for data communication control
Modem, 26: proxy server, 30: mixing / distributor,
31: tuner, 32: NTSC demodulator, 33: signal switching controller, 34: graphic display controller, 35: terminal control RF demodulator, 36: terminal control RF modulator, 3
7: System control unit, 38: Data communication control RF demodulator, 39: Data communication control RF modulator, 40: Data communication control unit, 41: Remote control light receiving unit, 42: Terminal operation pad, 60: 64QAM demodulator , 61: error correction means,
63: signal changeover switch, 65: MPEG decoder.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masami Nishida 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Visual Information Media Division of Hitachi, Ltd. (72) Inventor Shinji Shinji 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Address Co., Ltd. Visual Information Media Division, Hitachi, Ltd.

Claims (13)

[Claims] In a CATV system in which a center and a plurality of terminals are connected by a transmission path capable of transmitting data and two-way communication is performed between the center and the plurality of terminals, data such as a program menu is stored in the center station. WWW (World Wide
CAT having a Web) server, wherein the terminal uses a WWW browser to perform operations and calls data in the WWW server into the terminal, and uses this to display graphical menus and execute applications.
V system. 2. A CATV system in which a center and a plurality of terminals are connected by a transmission path through which data can be transmitted and two-way communication is performed between the center and the plurality of terminals, wherein data such as a program menu is stored in the center station. A CATV menu display method, comprising a WWW server, wherein the terminal performs an operation using a WWW browser to call data in the WWW server into the terminal, and performs a graphical menu display using the data. . 3. A CATV system in which a center and a plurality of terminals are connected by a transmission path capable of data transmission and perform bidirectional communication between the center and the plurality of terminals.
A CATV terminal having a browser, wherein a program menu or the like is displayed on a WWW browser using data downloaded from a WWW server at a center, and an application provided in a CATV network is operated on the WWW browser. 4. In a CATV system in which a center and a plurality of terminals are connected by a transmission path through which data can be transmitted and two-way communication is performed between the center and the plurality of terminals, a center station includes BS, CS for broadcasting. , VHF, UHF, FM broadcasting and other retransmission equipment and independent broadcasting equipment and terminals billing and contracts,
In addition to a terminal management device that manages equipment, the terminal control RF modem for performing communication of information such as the billing and contract and a WWW server that stores data such as menus and program guides displayed on the terminal, This WWW server is connected to the terminal through a dedicated data communication control RF modem, while the terminal is connected to a terminal control RF modem for bidirectional communication of billing and contract information with the center and the center WW.
It has an RF modulator / demodulator for data communication control for transmitting and receiving data to and from a W server, and further incorporates a WWW browser on an OS (operation system) for controlling the terminal. A graphical menu display is realized by reading menus and program information from the WWW server at the center and displaying them on the WWW browser, and centrally performing CATV application operations such as channel selection of programs on the browser. CATV system characterized by the above-mentioned. 5. The CATV system according to claim 4, wherein the WWW server in the center is a main server, and information that has been accessed once is stored, and when the same information is requested, the stored information is returned. A plurality of proxy servers each having a function of performing the function are installed in accordance with the number of terminals to be connected, and the frequencies of the data communication control RF modems connected to the respective proxy servers are different from each other. A CATV system characterized by ensuring a response speed to a request from a user within a certain range. 6. The CATV system according to claim 5, wherein said plurality of proxy servers are connected to RF modems for data communication control having different frequencies, respectively, whereas RF modulation for data communication control of a terminal is performed. The modulation frequency of the transmitter is determined by the terminal management device in the center from the terminal control R
It can be changed by an RF modulation frequency change command for data communication control sent via the F modem, and the terminal management device of the center station detects the amount of access to the plurality of proxy servers and reduces it to a certain amount or less. A CATV system comprising: instructing an arbitrary terminal to change a data communication control RF modulation frequency to change a modulation frequency of a data communication control RF modulator of the terminal. 7. A data communication control RF for transmitting / receiving data such as menu information to / from a proxy server in the center station in the CATV system according to claim 6.
The modulation / demodulation frequency of the modem is changed from the center station to the terminal control RF.
It can be set by a modulation / demodulation frequency control signal transmitted through a modem, and the modulation / demodulation frequency of the RF modulator / demodulator for data communication control has a certain variable range. CATV characterized by changing the control RF modulation frequency, and changing the modulation frequency of the data communication control RF modulator of the terminal in response to the instruction.
Terminal. 8. In a CATV system in which a center and a plurality of terminals are connected by a transmission path capable of data transmission and two-way communication is performed between the center and the plurality of terminals, the center station includes a BS, a CS for broadcasting. , VHF, UHF, FM broadcasting and other retransmission equipment and independent broadcasting equipment and terminals billing and contracts,
In addition to the terminal management device for managing the equipment, the terminal management device has a WWW server for storing data such as menus and program guides displayed on the terminal, and the WWW server and the terminal management device are connected to the terminal via a dedicated data communication control RF modem. The terminal has an RF modulator / demodulator for data communication control for the purpose of performing bidirectional communication of billing and contract information with the center and transmitting and receiving data to and from the WWW server of the center. A WWW browser is built into the OS (operation system) that controls the terminal, and menus and program information for operating the terminal are read from the WWW server at the center and displayed on the WWW browser to realize a graphical menu display. In addition, the operation of CATV applications such as program selection can be performed on the browser. CAT, which comprises carrying out the original manner
V system. 9. The CATV system according to claim 8, wherein the WWW server in the center according to claim 8 is a main server, and the information that has been accessed once is stored, and when the same information is requested, the storage is performed. A plurality of proxy servers each having a function of returning the received information are installed in accordance with the number of connected terminals, and the frequencies of the data communication control RF modems connected to the respective proxy servers are set to different menus using different frequencies. A CATV system wherein a response speed to a request from a terminal such as a display is secured within a certain range or more. 10. The CATV system according to claim 9, wherein said plurality of proxy servers are connected to data communication control RF modems having different frequencies, respectively. The modulation frequency of the transmitter can be changed by a data communication control RF modulation frequency change command sent from the terminal management device of the center via the RF modem for data communication control. Detects the amount of access to the proxy server and instructs any terminal to change the RF modulation frequency for data communication control so as to keep it below a certain amount and changes the modulation frequency of the RF modulator for data communication control of the terminal CATV system characterized by performing. 11. The CATV system according to claim 10, wherein an R for data communication control for transmitting / receiving data such as menu information to / from a proxy server in said center station.
The modulation / demodulation frequency of the F modulator / demodulator can be set by a modulation / demodulation frequency control signal transmitted from the center station through the RF for data communication control, and the modulation / demodulation frequency of the RF modulator / demodulator for data communication control has a certain variable range. The center may arbitrarily instruct the data communication control RF modulation frequency to be changed according to the traffic amount or the access amount of the cage system.
CA characterized by changing a modulation frequency of an F modulator
TV terminal. 12. The CATV system according to claim 1, wherein the center station has the same type of a modulator for broadcast signals and a modulator for data communication for transmitting data of a WWW server to a terminal. In the case of receiving a broadcast and W
A CATV system characterized by selecting a signal by switching a reception frequency by a tuner when receiving data from a WW server and receiving each signal or data using the same demodulator. 13. A CATV system according to claim 1, wherein a broadcast is received by switching a tuner frequency or a data is received from a WWW server, and a demodulator is used by using the same demodulator. Alternatively, a CATV terminal characterized by demodulating data.