JPH11163830A - Data communication method using catv system, communication center equipment for catv system and communication terminal equipment for catv system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data communication method for a CATV system in which a communication resource corresponding to a data communication service optimally operated at that point of time and a communication protocol is easily selected, and to provide a communication center equipment and a communication terminal equipment. SOLUTION: In the data communication method, data are communicated between a communication center equipment Cr and one communication terminal equipment T11-T1n or over interconnected by a transmission line 1 of the CATV system through the use of spread spectrum modulation where coding modulation and demodulation are conducted by a spread code. In this case, the communication center equipment Cr sends a control signal to the communication terminal equipment T11-T1n to set dynamically a spread band width, a frequency range of the spread band, and the spread code or the like for spread spectrum modulation in the data communication.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a data communication method using a transmission path of a CATV system, a communication center device for a CATV system, and a communication terminal device for a CATV system.

[0002]

2. Description of the Related Art Conventional spread spectrum modulation using C
In data communication in the ATV system, the spread bandwidth is fixed, and the transmission capacity, communication reliability, noise resistance, and communication response time are also constant.

[0003]

In the urban CATV system, in recent years, the number of channels and the number of services have been increased and the frequency band that can be used for data communication has been limited. In addition, due to the balance with other services, The available frequency band may change at different times. The required frequency band, communication reliability, noise resistance, communication response time, and the like are various depending on the type of data communication service. Nevertheless, the spread bandwidth is fixed in the data communication in the conventional CATV system,
Since the transmission capacity, communication reliability, noise resistance, and communication response time are also constant, the system was designed in consideration of the worst situation, and the communication performance of the system could not be sufficiently exhibited in normal times.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has a transmission capacity, a communication reliability, a noise resistance, and the like in accordance with a change in an environment in performing data communication.
It is possible to set the communication response time, and as a result, the transmission of the CATV system which can secure the communication resources optimally corresponding to the data communication service currently operated and easily select the communication protocol. It is an object of the present invention to provide a data communication method using a road, a communication center device for a CATV system, and a communication terminal device for a CATV system.

[0005]

A data communication method using a CATV system according to the present invention (Claim 1) comprises a CA
1 with the communication center device connected by the transmission line of the TV system
In the data communication method of performing data communication using spread spectrum modulation for performing coded modulation and demodulation with a spread code, a control signal is transmitted from the communication center apparatus to the communication terminal apparatus. By doing
The spread bandwidth of the spread spectrum modulation in the data communication is dynamically set.

A data communication method using a CATV system according to the present invention (Claim 2) is a communication method according to the data communication method (Claim 1), wherein the communication is performed from the communication terminal device to the communication center device in the communication center device. A noise level of an uplink, which is a line, is detected, and the spreading bandwidth is set based on the detected noise level.

A data communication method using a CATV system according to the present invention (Claim 3) is a communication method according to the data communication method (Claim 1), wherein the communication is performed in the communication center apparatus from the communication terminal apparatus to the communication center apparatus. The data frequency of the uplink which is a line is detected, and the spread bandwidth is set based on the detected data frequency.

According to a fourth aspect of the present invention, there is provided a data communication method using a CATV system, wherein a spread code is used between a communication center device connected to a CATV system transmission line and one or more communication terminal devices. In a data communication method for performing data communication using spread spectrum modulation for performing modulated modulation and demodulation, the communication center device detects a use state of a frequency in the transmission path, and transmits a signal from the communication center device to the communication terminal device. By transmitting the control signal, the frequency range of the spread band of the spread spectrum modulation in the data communication is dynamically set based on the usage state of the detected frequency.

A data communication method using a CATV system according to the present invention (claim 5) is a communication method according to the data communication method (claim 4), in which the communication center device transmits from the communication terminal device to the communication center device. The noise level of the uplink, which is a line, is also detected, and the frequency range of the spread band is set based on the detected noise level and the usage status of the detected frequency.

[0010] A data communication method using a CATV system according to the present invention (claim 6) is characterized in that a spread code is used between a communication center device and one or more communication terminal devices connected by a transmission path of the CATV system. In a data communication method for performing data communication using spread spectrum modulation for performing modulated modulation and demodulation, a control signal is transmitted from the communication center device to the communication terminal device so that the spread code is transmitted to the one or more communication terminals. This is dynamically allocated to a terminal device.

[0011] In the data communication method using the CATV system according to the present invention (claim 7), in the data communication method (claim 6), a communication from the communication terminal device to the communication center device in the communication center device. A noise level of an uplink, which is a line, is detected, and the spreading code is assigned based on the detected noise level.

In the data communication method using the CATV system according to the present invention (claim 8), in the data communication method (claim 6), the communication center apparatus detects the data frequency of the uplink and detects the data frequency. The spreading code is assigned based on the data frequency obtained.

[0013] In the data communication method using the CATV system according to the present invention (claim 9), in the data communication method (claims 6 to 8), the spreading code to be allocated to the communication terminal device may be the control signal. A separate spreading code is used to spread the signal below the noise level of the downlink, which is the communication line from the communication center apparatus to the communication terminal apparatus, and transmit the spread signal.

According to a tenth aspect of the present invention, there is provided a data communication method using a CATV system, wherein a spread code is used between a communication center device connected to a CATV system transmission line and one or more communication terminal devices. In a data communication method for performing data communication using spread spectrum modulation for performing modulated modulation and demodulation, a control signal is transmitted from the communication center apparatus to the communication terminal apparatus so that the control signal is code-divided by the spread code and the same. A plurality of communication lines multiplexed in the same frequency band of a transmission line are used to transmit data for the same purpose.

[0015] In the data communication method using the CATV system according to the present invention (claim 11), in the data communication method (claim 10), the same data is transmitted through each of the plurality of communication lines. Is what it is.

According to a data communication method using a CATV system according to the present invention (claim 12), in the data communication method (claim 10), data capable of correcting an error of the data together with the data is provided. , Through the plurality of communication lines.

The data communication method using a CATV system according to the present invention (Claim 13) is the data communication method (Claims 10 to 12), wherein the communication center device sends the communication center device to the communication center device. The system detects a noise level of an up line which is a communication line going to the terminal, and transmits the control signal based on the detected noise level.

The data communication method using a CATV system according to the present invention (Claim 14) is the data communication method (Claims 10 to 12), wherein the communication center device transmits the communication center device to the communication center device. It detects the data frequency of the uplink line, which is the communication line going to, and transmits the control signal based on the detected data frequency.

In the data communication method using the CATV system according to the present invention (claim 15), in the data communication method (claim 14), the communication center device also detects the uplink noise level, and The control signal is transmitted based on the detected noise level and the detected data frequency.

[0020] In the data communication method using a CATV system according to the present invention (claim 16), in the data communication method (claims 1 to 15), the communication terminal device may include communication data in a header portion of the communication terminal. Apparatus identification information is added and transmitted to an uplink, which is a communication line toward the communication center device, and the communication center device transmits the transmitted communication data to a downlink, which is a communication line toward the communication terminal device. It is intended to be sent to.

The data communication method using the CATV system according to the present invention (claim 17) is the data communication method (claims 6 to 16) wherein polling is performed between the communication center device and the communication terminal device. The data communication based on the system and the data communication based on the free calling communication system from the communication terminal apparatus to the communication center apparatus are code-multiplexed using the spreading code.

[0022] In the data communication method using the CATV system according to the present invention (claim 18), in the data communication method (claim 17), the communication center device manages a communication frequency for each of the communication terminal devices. Perform data communication by a polling method with a communication terminal device whose communication frequency to be managed is lower than a predetermined value, and perform data communication by a free call communication method with a communication terminal device whose communication frequency to be managed is higher than the predetermined value. That's what we do.

[0023] A communication center apparatus for a CATV system according to the present invention (claim 19) performs coded modulation and demodulation with a spread code with one or more communication terminal apparatuses connected by a transmission path of the CATV system. In a communication center apparatus for performing data communication using spread spectrum modulation, a spread bandwidth setting means for setting a spread bandwidth of the spread spectrum modulation in the data communication, and a spread bandwidth set by the spread bandwidth setting means. A control signal transmitting means for transmitting a control signal for setting the communication terminal to the one or more communication terminal devices.

The communication center apparatus for a CATV system according to the present invention (Claim 20) is the communication center apparatus (Claim 19) wherein the noise in the uplink is a communication line from the communication terminal apparatus to the communication center apparatus. There is provided a noise level detecting means for detecting a level, and the spread bandwidth setting means sets the spread bandwidth based on the noise level detected by the noise level detecting means.

The communication center apparatus for a CATV system according to the present invention (Claim 21) is the communication center apparatus (Claim 19) wherein the data of the uplink line is a communication line from the communication terminal apparatus to the communication center apparatus. It has a data frequency detecting means for detecting the frequency, and the spread bandwidth setting means sets the spread bandwidth based on the data frequency detected by the data frequency detecting means.

A CATV system communication center device according to the present invention (claim 22) performs coded modulation and demodulation with a spread code with one or more communication terminal devices connected via a CATV system transmission path. In a communication center apparatus for performing data communication using spread spectrum modulation, a frequency band use state detecting means for detecting a use state of a frequency in the transmission path, and a frequency use state detected by the frequency band use state detection means A spread band frequency range setting means for setting a frequency range of a spread band of the spread spectrum modulation in the data communication, and a frequency band of the spread band set by the spread band frequency range setting means for setting the communication terminal to the communication terminal. Control signal transmitting means for transmitting a control signal to the one or more communication terminal devices.

The communication center device for a CATV system according to the present invention (Claim 23) is the communication center device (Claim 22) wherein the noise of the uplink is a communication line from the communication terminal device to the communication center device. Noise level detecting means for detecting a level, wherein the spread band frequency range setting means is based on the noise level detected by the noise level detecting means and the frequency usage detected by the frequency band usage status detecting means. , To set the frequency range of the spread band.

A CATV system communication center apparatus according to the present invention (claim 24) performs coded modulation and demodulation with a spread code with one or more communication terminal apparatuses connected by a CATV system transmission path. In a communication center apparatus for performing data communication using spread spectrum modulation, a spread code setting means for setting the spread code for each of the communication terminals, and a spread code set by the spread code setting means for the communication terminal Control signal transmitting means for transmitting a control signal to the communication terminal device to each of the communication terminal devices.

The communication center device for a CATV system according to the present invention (Claim 25) is the communication center device (Claim 24) wherein the noise of the uplink is a communication line from the communication terminal device to the communication center device. There is provided noise level detecting means for detecting a level, and the spreading code setting means sets the spreading code based on the noise level detected by the noise level detecting means.

The communication center apparatus for a CATV system according to the present invention (Claim 26) is the communication center apparatus (Claim 24) wherein the data of the uplink is a communication line from the communication terminal apparatus to the communication center apparatus. There is provided data frequency detecting means for detecting the frequency, and the spreading code setting means sets the spreading code based on the data frequency detected by the data frequency detecting means.

In the communication center device for a CATV system according to the present invention (claim 27), in the communication center device (claims 24 to 26), the control signal transmitting means transmits the control signal to the communication terminal device. A spreading code different from the spreading code to be set is used, and the spread code is spread below the noise level of a downlink, which is a communication line from the communication center apparatus to the communication terminal apparatus, and transmitted.

A CATV system communication center apparatus according to the present invention (claim 28) performs coded modulation and demodulation with a spread code with one or more communication terminal apparatuses connected via a CATV system transmission path. In a communication center device that performs data communication using spread spectrum modulation, a plurality of communication lines that are code-divided by the spread code and multiplexed in the same frequency band of the same transmission path are connected to any of the communication terminal devices. Communication control means for transmitting and receiving data of the same purpose between the plurality of communication lines, and when the plurality of communication lines are used for transmitting and receiving data of the same purpose, the communication terminal is operated by Control signal transmitting means for transmitting a control signal for transmitting and receiving the data to the communication terminal devices corresponding to the plurality of communication lines.

According to a communication center apparatus for a CATV system according to the present invention (claim 29), in the communication center apparatus (claim 28), the communication control means transmits the same data through each of the plurality of communication lines. The data transmitted to the communication terminal devices corresponding to the plurality of communication lines and the correctness of the same data received through the plurality of communication lines can be determined by majority decision.

In the communication center device for a CATV system according to the present invention (claim 30), in the communication center device (claim 28), the communication control means may correct an error of the certain data together with the certain data. It is possible to transmit possible data to the communication terminal device corresponding to the plurality of communication lines through the plurality of communication lines, and to correct certain data received through the plurality of communication lines and an error in the certain data. With respect to data, an error of the certain data can be corrected using data capable of correcting an error of the certain data.

A communication center apparatus for a CATV system according to the present invention (claim 31) is the communication center apparatus (claims 28 to 30) wherein the upstream line is a communication line from the communication terminal apparatus to the communication center apparatus. And a control signal transmitting means for transmitting the control signal based on the noise level detected by the noise level detecting means.

The communication center apparatus for a CATV system according to the present invention (Claim 32) is the communication center apparatus (Claims 28 to 30) wherein the upstream line is a communication line from the communication terminal apparatus to the communication center apparatus. And a control signal transmitting means for transmitting the control signal based on the data frequency detected by the data frequency detecting means.

A CATV system communication center device according to the present invention (claim 33) is the communication center device (claim 32), further comprising noise level detecting means for detecting the uplink noise level, The signal transmitting means transmits the control signal based on the noise level detected by the noise level detecting means and the data frequency detected by the data frequency detecting means.

The communication center device for a CATV system according to the present invention (claim 34) is the communication center device (claims 19 to 33) wherein the upstream line is a communication line from the communication terminal device to the communication center device. When receiving communication data in which the communication terminal device recognition information is added to the header portion through the communication device, the received communication data is transmitted to the downlink which is the communication line from the communication center device to the communication terminal device. It is composed.

A communication terminal device for a CATV system according to the present invention (Claim 35) is a spread spectrum modulation device that performs coding modulation and demodulation with a spreading code between the communication terminal device and a communication center device connected through a transmission path of the CATV system. Control signal receiving means for receiving a control signal transmitted from the communication center apparatus for setting a spread bandwidth of spread spectrum modulation in the data communication, the control terminal receiving means for performing data communication using A spreading bandwidth setting means for setting the spreading bandwidth based on the control signal received by the signal receiving means.

A communication terminal device for a CATV system according to the present invention (Claim 36) is a spread spectrum modulation device that performs coded modulation and demodulation with a spread code with a communication center device connected to a CATV system transmission line. In a communication terminal device that performs data communication using, a control signal receiving unit that receives a control signal for setting a frequency range of a spread band of spread spectrum modulation in the data communication transmitted from the communication center device, A spreading band frequency range setting means for setting a frequency range of the spreading band based on the control signal received by the control signal receiving means.

A communication terminal apparatus for a CATV system according to the present invention (Claim 37) performs spread spectrum modulation for performing coding modulation and demodulation with a spreading code between the communication terminal apparatus and a communication center apparatus connected through a transmission path of the CATV system. Control signal receiving means for receiving a control signal transmitted from the communication center apparatus for setting a spread code of spread spectrum modulation in the data communication, the control signal receiving means comprising: Spreading code setting means for setting the spreading code based on the control signal received by the receiving means.

A communication terminal device for a CATV system according to the present invention (Claim 38) is a spread spectrum modulation device that performs coded modulation and demodulation with a spread code with a communication center device connected to a CATV system transmission line. Control signal receiving means for receiving a control signal transmitted from the communication center apparatus for transmitting and receiving data of the same purpose over a plurality of communication lines; Communication control means for transmitting and receiving data for the same purpose using a plurality of communication lines which are code-divided by the spreading code and multiplexed in the same frequency band of the same transmission path based on the control signal received by the means. It is provided with.

A communication terminal device for a CATV system according to the present invention (Claim 39) is the communication terminal device (Claim 3).
In 8), the communication control means transmits the same data
The data is transmitted to the communication center device through each of the plurality of communication lines, and the validity of the same data received through the plurality of communication lines can be determined by majority decision.

The communication terminal for a CATV system according to the present invention (Claim 40) is the communication terminal (Claim 3).
8) In the communication control unit, the communication control means transmits the data capable of correcting an error of the certain data together with the certain data to the communication center device through the plurality of communication lines, and receives the data through the plurality of communication lines. It is possible to correct the error of the certain data using the data capable of correcting the error of the certain data with respect to the certain data and the data that can correct the error of the certain data. It is like that.

The communication terminal for a CATV system according to the present invention (Claim 41) includes the communication terminal (Claim 35).
40) to 40), transmitting the communication data to the communication center apparatus by adding the communication terminal device recognition information to the header portion thereof, and transmitting the communication data addressed to itself to the communication center device based on the communication terminal device recognition information added to the header portion. It is configured to be able to determine and receive.

[0046]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a communication center apparatus for a CATV system according to Embodiment 1 of the present invention,
CA using communication terminal device for CATV system
It is a block diagram showing the outline of a TV system.

In the figure, Cr is a communication center device (hereinafter, referred to as a center) for providing various data services, and a CATV transmission line (hereinafter, referred to as a transmission line) 1 using a coaxial cable is drawn out of the center Cr. A plurality of communication terminal devices (hereinafter, referred to as terminals) Tl1 to Tln installed in each dwelling unit are connected to the transmission line 1. Each terminal Tl1 ~
A television device (hereinafter, referred to as a TV) 2 is connected to Tln, and the TV 2 allows the CATV subscriber to select a response content when a service requiring a response from the CATV subscriber is performed. A remote controller 3 is provided. The transmission line 1 is assigned a frequency band to be used for each data service to be provided (not shown). The transmission line 1 also goes from the terminals Tl1 to Tln to the center Cr and from the center Cr to the terminals Tl1 to Tln. And downlinks, and are assigned different frequency bands.

FIG. 2 is a block diagram showing details of the configuration of the center Cr in FIG. In the figure, the center Cr has a communication control unit 4, an SS transmission unit 5, an SS reception unit 6, a noise level detection unit 10, a data frequency detection unit 21, and a frequency use status detection unit 22.

The communication control unit 4 receives the reception data 8 output from the SS reception unit 6, sends the transmission data 7 to the terminal to the SS transmission unit 5, and controls data communication with the terminal. In addition, the transmission data 7 and the reception data 8 are processed, and various data processing is performed. The setting of a threshold value and the transmission of a setting command and data, which will be described later, are performed by inputting a required input from the outside using input means (not shown). Also,
The spreading band control signal 9 is transmitted to the SS transmitting unit 5 and the SS receiving unit 6
To set the spreading code used for the spread spectrum modulation in the SS transmitting section 5 and the SS receiving section 6, the spreading bandwidth, and the frequency range of the spreading band. The setting of the spreading band is performed by selecting the clock speed of the spreading code, and the setting of the frequency range of the spreading band is performed by selecting the carrier frequency of the transmission signal. Further, a PN code sequence or the like is used as the spreading code.

The SS transmission unit 5 encodes the transmission data 7 output from the communication control unit 4, performs spread spectrum modulation on the encoded transmission data 7 using a spreading code, and converts the modulated transmission signal into a transmission path. 1 outgoing line.

The SS receiving unit 6 receives a spread spectrum modulated communication signal transmitted from a terminal via the uplink of the transmission line 1, demodulates the received communication signal using a spread code, and demodulates the received communication signal. The communication signal is decoded into reception data 8, and the reception data 8 is output to the communication control unit 4.

The noise level detector 10 is composed of a tuner, a receiving circuit, etc., detects the noise level of the uplink of the transmission line 1 and outputs this to the communication controller 4.
The data frequency detection unit 21 is configured by a counter or the like for counting the number of data, detects the frequency of communication data (hereinafter referred to as “uplink data”) transmitted through the uplink of the transmission line 1, and detects the frequency of the communication data. Output to The frequency use status detecting unit is configured by a tuner, a receiving circuit, and the like, detects whether or not there is an unused frequency band among the respective frequency bands of the transmission line 1 and outputs this to the communication control unit 4. .

FIG. 3 is a block diagram showing details of the configuration of the terminals Tl1 to Tln in FIG. In the figure, terminals Tl1 to Tln
Has a communication control unit 24, an SS transmission unit 25, and an SS reception unit 26. The SS transmitting unit 25 and the SS receiving unit 26 correspond to the SS transmitting units 5 and SS of the center Cr in FIG.
The configuration is the same as that of the receiving unit 6.

The communication control unit 24 includes the SS receiving unit 2
Various data processing is performed on the received data 28 output from the TV 6, the received data 28 is output to the TV, and the transmission data 27 input from the TV is output to the SS transmitting unit 25. Further, based on the setting command transmitted from the center, the spread band control signal 29 is output to the SS transmitting section 25 and the SS receiving section 26, and the SS transmitting section 25 is output.
In addition, the setting of the spreading code used for the spread spectrum modulation in the SS receiving unit 26, the setting of the spreading bandwidth, and the setting of the frequency range of the spreading band are performed. Also, these spreading bandwidths,
The setting of the frequency range of the spread band is performed in the same manner as the communication control unit of the center.

FIG. 4 is a diagram showing a format of a packet of communication data according to the first embodiment.
FIG. 4B shows a data packet, and FIG. 4B shows a setting command. In the figure, reference numeral 11 denotes a data packet (hereinafter, referred to as a data packet), which is used for bidirectional communication from the center to the terminal and from the terminal to the center. Reference numeral 12 denotes a setting command packet (hereinafter, referred to as a setting command), which is used only for communication from the center to the terminal. The data packet 11 includes a destination address (communication terminal device recognition information) at the head and data of another part. The setting command 12 includes a destination address at the head, an allocated frequency band at the center, It consists of an assigned spreading code at the end. The packets 11 and 12 are created by the communication control unit of the center and the terminal. The communication control unit of the center and the terminal recognizes the destination addresses of the packets 11 and 12 and determines the packet addressed to itself. It is configured to receive.

FIG. 5 shows a spread code according to the first embodiment,
FIG. 5A is a schematic diagram showing how to dynamically set a spreading bandwidth, and FIG. 5A is a diagram showing a case where a spreading code is set to be small and a spreading bandwidth is set to be large; FIG. FIG. 4 is a diagram illustrating a case where a spread bandwidth is set small. In the figure, Bdo indicates an occupied band which is a frequency band allocated to a certain service, and in order to facilitate the description, an uplink and a downlink are overlapped. a to d indicate spreading codes, and L1 to L4 indicate communication lines obtained by code division by the spreading codes a to d. In addition, each communication line L
1 to L4 are each assigned a dedicated frequency band, and code multiplexing is not performed in the same frequency band. Therefore, when the number of spreading codes is increased, the spreading bandwidth is reduced, and when the spreading bandwidth is increased, the number of spreading codes is reduced. Further, since the number of spreading codes is limited, the spreading codes are allocated to each predetermined group of terminals.

The setting of the spreading code and the spreading bandwidth is performed as follows. That is, at the center, the operator detects the uplink noise level detected by the noise level detector,
Alternatively, the uplink data frequency detected by the data frequency detection unit is compared with a predetermined threshold, and the spreading code is reduced to increase the spreading bandwidth, or the spreading code is increased to reduce the spreading bandwidth. Is determined, and the result of the determination is input to the communication control unit. Then, the communication control unit sets the spreading code and the spreading bandwidth of the center in accordance with the input determination result, and also causes the terminal to set the spreading code and the spreading bandwidth to those set in FIG.
The setting command 12 of (b) is transmitted to each terminal, and the communication control unit of the terminal that has received the setting command sets the spreading code and the spreading bandwidth according to the setting command.

FIG. 6 shows a usage pattern of a communication line when code division multiplexing is performed in the same frequency band and a plurality of communication lines obtained by the code division multiplexing are used for transmitting different target data. FIG. In the figure, a to d denote spreading codes, L1 to L4 denote multiplexed communication lines obtained by code division by the spreading codes a to d, and 11a to 11d denote data packets transmitted through the communication lines L1 to L4. Is shown. This usage mode is a usage mode in a normal case, and each of the communication lines L1 to L1
4, data packets 11 a to 11 d having separate target data A to D are transmitted, respectively.

FIG. 7 is a schematic diagram showing a use form of a communication line when a plurality of communication lines obtained by code division multiplexing are used for transmitting data of the same purpose. In the figure, this usage mode is a usage mode in which the anti-noise performance is enhanced to ensure communication reliability. For example, a data packet 11a having the same data A is transmitted through each of the communication lines L1 to L4. Is done. Switching between the above-described normal use mode and the use mode for enhancing the noise resistance performance is performed as follows. That is,
At the center, the operator compares the uplink noise level detected by the noise level detection unit and the uplink data frequency detected by the data frequency detection unit with the respective predetermined thresholds, and It is determined whether or not it should be performed, and the determination result is input to the communication control unit. Then, the communication control unit sets the usage mode of the center according to the input determination result, and sets a terminal to set the usage mode to the set usage mode (not shown).
Is transmitted to the corresponding terminal, and the communication control unit of the terminal that has received the setting command sets the use mode according to the setting command.

When the communication control units of the center and the terminal receive the data packet 11a having the same data A via the plurality of communication lines L1 to L4, the communication control unit determines the validity of the data packet 11a by, for example, majority decision. It is configured to be.

In order to improve noise immunity by using a plurality of communication lines obtained by code division multiplexing to transmit data for the same purpose, another use form may be adopted.

FIG. 8 is a schematic diagram showing an example of such another use mode. In this figure, in this usage pattern, as data for the same purpose, certain data and an error correction code for transmitting the data without error are transmitted through a plurality of (two in this embodiment) communication lines. That is, for example, the data packet 11a having the data A and the data packet 11e having the error correction code A 'of the data A are respectively connected to the communication line L1 corresponding to the spreading code a and the communication line L2 corresponding to the spreading code b. Sent through
The data packet 11b having the data B and the data packet 11f having the error correction code B 'of the data B are transmitted through the communication line L3 corresponding to the spreading code c and the communication line L4 corresponding to the spreading code d, respectively. . Then, on the receiving side, data A is corrected using the correction code A ', and data B is corrected using the correction code B'. The switching of the usage mode is performed in the same manner as in the case of FIG.

FIG. 9 is a schematic diagram showing a method of dynamically setting a spreading bandwidth when code division multiplexing is performed. FIG. 9A shows a setting of a small spreading bandwidth to secure a large number of communication lines. FIG. 9B is a diagram showing a case in which the number of communication lines is reduced and the spreading bandwidth is set large to ensure the reliability of the communication lines. In the figure, Bd1 to Bd8 indicate unit occupied bands that are frequency bands allocated to each terminal group. In each of the unit occupied bands Bd1 to Bd8, as shown in FIG. Divided and multiplexed communication lines L1 to L4 are formed.

The spreading bandwidth and the unit occupied band Bd1 to Bd8
Is set as follows. That is, at the center, the operator compares the uplink noise level detected by the noise level detection unit and the uplink data frequency detected by the data frequency detection unit with respective predetermined thresholds,
Decide whether to set a small spread bandwidth to secure more communication lines or to reduce the number of communication lines and set a larger spread bandwidth to ensure the reliability of the communication line, and send the result of determination to the communication control unit. input. Then, the communication control unit sets the spread bandwidth and the frequency band of the center according to the input determination result, and also causes the terminal to set the spread bandwidth and the frequency band to the set spread bandwidth and the frequency band as shown in FIG. ) Is transmitted to each terminal, and the communication control unit of the terminal that has received the setting command sets a spreading bandwidth and a frequency band according to the setting command.

Next, the communication center apparatus for the CATV system according to the first embodiment configured as described above, and C
The operation of the communication terminal device for the ATV system, that is, the data communication method using the CATV system according to the first embodiment using these devices will be described with reference to FIGS.

First, an outline of the data communication method according to the first embodiment will be described. 1, in the CATV system according to the first embodiment, a data communication signal of TV broadcasting and other various data services is distributed from a center Cr to terminals Tl1 to Tln via a transmission line 1. In each dwelling unit, the CATV subscriber transmits the delivered signal to the terminal T.
It can be viewed via l1 to Tln and TV2.

Next, the details of the data communication method according to the first embodiment will be described using a case where a quiz response program is implemented using a CATV system as an example. For the quiz response program, it is assumed that the CATV subscriber selects an answer with the remote controller 3 in FIG. 1 while watching the program.

First, prior to the start of a program, a communication resource allocation process required for program operation is performed as described below. 1 to 5, in a center Cr, a noise level detecting unit 10 detects an uplink noise level of the transmission line 1, and a noise level detected by a communication control unit 4 based on a preset reference threshold value. Is higher, the spreading bandwidth is reset for the terminal to be served by the setting command 12 so as to increase the spreading bandwidth. The setting command 12 uses a dedicated spreading code and a spreading band common to all terminals so that the setting command 12 can be received regardless of the state of the terminal.

Here, by increasing the length of the spreading code, it is possible to spread the setting command below the noise level of the transmission line 1 and transmit the same, and therefore, highly confidential communication and data transfer are possible. It is possible to do.

The reason why the noise level is detected is that if the noise level is high, the answer or the like transmitted from the terminals Tl1 to Tln may not be correctly received by the center Cr, and the noise level is set to the reference threshold value. If higher, transmission quality is ensured by increasing the spread bandwidth of spread spectrum modulation used for data transmission from terminals Tl1 to Tln. The relationship between the noise level and the spreading bandwidth is represented by the formula: C = W × log ₂ {(P + N) / N}. Here, C [bps] is communication capacity (capacity that the communication line can transmit without error), W [Hz] is transmission bandwidth (spread bandwidth here), P [W] is average transmission power, N [W
] Is the average noise power. As is clear from the above equation, as the noise level increases, the communication capacity in the transmission path 1 decreases. However, if the spread bandwidth is widened, it is possible to secure the communication capacity even when the noise level becomes high.
Therefore, the center Cr sets the spread bandwidth in its own reception in accordance with the noise state of the uplink of the transmission line 1, and sends data and commands (excluding the setting command 12) to the center Cr for the terminals Tl1 to Tln. The setting command 12 is transmitted in order to set the spread bandwidth in the case of transmitting communication data such as ()) using the uplink according to the noise state of the uplink of the transmission line 1. Terminal Tl1 ~
At Tln, the transmitted setting command 12 is received,
The spread bandwidth is set by changing the clock frequency and the like according to the received setting command 12. When the noise level of the transmission line 1 is high, the center Cr preliminarily sets the terminals Tl1 to Tl1 so as to set a large spreading bandwidth.
The setting command 12 is transmitted to ln to secure transmission quality.
On the other hand, when the noise level of the transmission line 1 is low, the center C
r is the terminal Tl1 to Tln so that the spreading bandwidth is set narrow.
To transmit a setting command 12 to effectively use frequency resources.

In the data communication method according to the first embodiment, the center Cr and the terminals Tl1 to Tl1 to
By securing a plurality of communication lines with Tln and using some of them as lines for transmitting data of the same purpose, transmission quality can be ensured even when the noise level of the transmission line 1 is high. it can. As a result, noise immunity can be improved as in the case of dynamically setting the spread bandwidth. Specifically, the following two communication line usage patterns can be selected.
The use of these two communication lines will be described with reference to FIGS.

First, in a normal communication line usage mode, as shown in FIG. 6, for example, four communication lines L1 to L4 obtained by code division multiplexing have different purposes through respective communication lines L1 to L4. The data packets 11a to 11d having the data A to D are transmitted, respectively.

On the other hand, in the use mode of the first communication line, as shown in FIG. 7, a data packet 11a having the same data A is transmitted through four communication lines L1 to L4. In this case, the receiving side has four communication lines L1 to L1.
The data A of L4 is simultaneously received, and the validity of the received data A is determined by majority decision. Thereby, even if a data error occurs in the data A, correct data can be received and recognized. In this case, as in the case of setting the spreading bandwidth, the center Cr notifies the terminals Tl1 to Tln of the fact and the spreading code to be used by a setting command (not shown) for switching to this usage pattern. Keep it.

In the use mode of the second communication line, as shown in FIG.
a and a data packet 11e having an error correction code A 'of data A are transmitted through two communication lines L1 and L2, respectively. Similarly, a data packet 11b having data B and an error correction code B of data B are transmitted. 'With two communication lines L3 and L3
4 respectively. Then, on the receiving side, data A is corrected using the correction code A ', and data B is corrected using the correction code B'. This allows
The noise resistance performance can be improved as in the case of FIG.

With the above processing, the initial spreading band, the use form of the communication line, and the like are set, whereby the communication resources required for the program operation are allocated. Thereafter, the noise level of the uplink is always monitored. Then, if necessary, the spreading band and the line use mode are reset.

Next, the operation of the quiz response program will be described.
1 to 9, first, a quiz response program is broadcast through the CATV system, and recruitment of quiz response program participants is performed. In this case, since the center Cr does not know the audience participating in the quiz at the time of the start of the program, all the terminals Tl1 to Tln are checked by polling for the presence or absence of the quiz response program. In this case, as shown in FIG.
Different spreading codes a for each predetermined group of terminals
Polling is performed by dividing the frequency band using .about.d. Within each group, the communication destination (center Cr, terminals Tl1 to Tln) is specified by the destination address. The number of groups is determined by the uplink noise level checked in advance. That is, when the noise level is high, as shown in FIG. 5 (a), the number of spreading codes is suppressed to improve the noise resistance performance, and when the noise level is low, as shown in FIG. 5 (b), By increasing the number of groups by increasing the number of spreading codes, the communication lines L1 to L4
And increase the survey time.

Next, the question of the alternative method is presented, and after the answer is closed, polling is performed on the terminal to be participated identified in the quiz participant survey in the same manner as in the quiz participant survey to divide the frequency band. To collect answers. Also in this case, the number of groups is adjusted according to the noise level.

At this time, a quiz-response program participant from the middle is checked by further using a spreading code other than the spreading code used for polling. At first, participation is accepted by transmitting data packet 11 from the terminal by free call, but if this uplink data packet 11 increases frequently, packet collision occurs and data collection efficiency decreases, so that The center Cr detects the uplink data frequency, and switches to participation acceptance by polling when the frequency becomes equal to or higher than a preset reference frequency. The participation by polling is also performed by dividing the frequency band using a spreading code different from the spreading code of the communication line for collecting the answer.

On the other hand, if the total parameters of the terminals Tl1 to Tln are relatively large and it is inefficient to investigate participants in advance,
Data is collected by free call from terminals Tl1 to Tln without prior investigation. However, since the number of available spreading codes is limited, if the entire band of the occupied band Bdo, which is an available frequency band, is used as a spreading band, codes cannot be assigned to each terminal. If it is high, packet collisions may occur frequently. Accordingly, as shown in FIG. 8, the occupied bandwidth Bdo (bandwidth W = Wo) at the start of the program is changed to a plurality (in the figure, 8 and 2 are illustrated) of the unit occupied bandwidths Bd1 to Bd8. Divided into
Code division multiplexing is performed in each of the unit occupied bands Bd1 to Bd8. The switching to the usage mode of the communication line is performed by the center Cr in the same manner as the switching of the usage mode of the communication line described above.
A setting command 1 that sets its own spreading band and spreading code and notifies the terminals Tl1 to Tln1 of the allocated frequency band (spreading band) and the allocated spreading code.
2 is transmitted.

That is, when the frequency of the uplink data detected by the noise level detector 10 of the center Cr is higher than a predetermined reference threshold, as shown in FIG.
Each spreading terminal (bandwidth of unit occupied bands Bd1 to Bd8) is set to be the smallest (bandwidth W = Wo / 8), and code division multiplexing is performed in each of the unit occupied bands Bd1 to Bd8, thereby enabling each terminal. A communication line ((L1 to L4) × 8) between Tl1 to Tln1 and the center Cr is secured. In this case, a setting command 12 for minimizing the spread bandwidth is transmitted from the center Cr to the terminals Tl1 to Tln1.

On the other hand, when the uplink data frequency is low, it is not necessary to increase the spreading code even if the spreading bandwidth is narrowed.
Therefore, when the uplink data frequency is lower than the reference threshold value, the spreading bandwidth (the bandwidth of the unit occupied bandwidths Bd1 and Bd2) is set wide as shown in FIG. 8B (bandwidth W = Wo).
/ 2) Enhance noise immunity and ensure communication reliability. In this case, a setting command 12 for increasing the spreading bandwidth is transmitted from the center Cr to the terminals Tl1 to Tln1.

When the frequency of uplink data is low,
Instead of increasing the spreading bandwidth as described above, FIG.
As shown in FIG. 8, a plurality of communication lines L1 to L4 obtained by code division multiplexing are used to transmit data of the same purpose, thereby improving noise immunity and improving communication reliability. May be secured.

In the center Cr, the frequency use status detecting section 22 constantly monitors the available frequency band of the transmission line 1, and if there is an available band, the available band is used.
The frequency range of the spreading band, the spreading bandwidth, and the spreading code shown in FIGS. 5 and 9 are reset for the terminals Tl1 to Tln. Thereby, according to the frequency use situation of the transmission line 1,
Communication resources such as a frequency band, noise resistance, and the number of communication lines can be allocated.

To transmit data from the terminals Tl1 to Tln to the center Cr, the address of the center Cr is added to the data packet 11 as the destination address. However, the address of another terminal is added to the data packet 11 as the destination address. When the data packet 11 is transmitted to the upstream line, the communication control unit 4 of the center Cr is configured to return such a data packet 11 to the downstream line. Accordingly, this allows data communication between terminals.

In the first embodiment, a spread code, a spread bandwidth, and a plurality of communication lines used for data transmission for the same purpose are detected based on a noise level detected by the center Cr or an uplink data frequency. Although the setting is made, it may be set based on both the noise level and the frequency of the uplink data. As a result, communication resources can be more accurately allocated.

In the first embodiment, the setting of the spreading code and the spreading bandwidth, switching to the usage mode of the communication line,
And the setting of the unit occupied band is performed by the operator's determination, and the communication control unit of the center automatically sets the uplink noise level, the uplink data frequency, and the frequency usage status, respectively. May be set by comparing with a predetermined threshold value.

In the first embodiment, the investigation by polling is performed by dividing the frequency band. However, the investigation may be performed by code division multiplexing. In the first embodiment, the quiz response program has been described as an example. However, the present invention can be applied to all data communication applications between the center and the terminal.

[0088]

As described above, according to the first aspect of the present invention,
Since the spread bandwidth of the spread spectrum modulation in the data communication between the communication center device and the communication terminal device is dynamically set, the spread bandwidth is changed according to the change of the environment in performing the data communication. Can be set,
As a result, it becomes possible to easily secure communication resources suitable for the data communication service currently operated and to select a communication protocol.

According to the invention of claim 2, according to claim 1,
In the invention of the above, since the noise level of the uplink is detected and the spreading bandwidth is set based on the detected noise level, the spreading bandwidth is set relatively large when the noise level is high. Improve noise resistance,
When the noise level is low, it is possible to save the use of the frequency resources by setting the spreading bandwidth relatively small, and it is possible to accurately secure the communication resources for the change in the noise level.

According to the third aspect of the present invention, in the first aspect of the present invention, the data frequency of the uplink is detected, and the spreading bandwidth is set based on the detected uplink data frequency. When the frequency of uplink data is high, the spreading bandwidth is set relatively small to secure a large number of communication lines obtained by frequency division multiplexing, and when the frequency of uplink data is low, the spreading bandwidth is set relatively large to withstand. Noise performance can be improved, and communication resources and the like can be accurately secured with respect to a change in uplink data frequency.

According to the fourth aspect of the present invention, the use status of the frequency in the transmission path of the CATV system is detected, and the data communication between the communication center device and the communication terminal device is performed based on the detected use status of the frequency. Because the frequency range of the spread spectrum of the spread spectrum modulation is dynamically set, it is possible to change the frequency range of the spread band and use the vacant frequency band, and effectively use the frequency resources can do.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the noise level of the uplink is also detected, and based on the detected noise level and the use status of the detected frequency, the spread band is determined. Since the frequency range is set, it is possible to set the optimum bandwidth and frequency of the spread band used for data communication by judging from both the noise level and the usage status of the frequency, and more accurately. , Communication resources, etc., and effective use of frequency resources.

According to the invention of claim 6, the spread code of the spread spectrum modulation in the data communication between the communication center device and the communication terminal device is dynamically assigned to the communication terminal device. In the case of performing frequency division multiplexing, it is possible to set a spreading code according to a change in environment in performing data communication, and as a result, a communication resource adapted to a data communication service operated at that time can be set. It is possible to easily secure and select a communication protocol.

According to the invention of claim 7, in the invention of claim 6, the noise level of the uplink is detected and the spreading code is assigned based on the detected noise level. When the noise level is high, the number of spreading codes is suppressed to increase the spreading bandwidth to improve noise resistance, and when the noise level is low, the spreading bandwidth is reduced and the number of spreading codes is increased to increase the communication line. It is possible to secure a large number, and it is possible to appropriately secure communication resources for a change in noise level.

According to the invention of claim 8, in the invention of claim 6, the data frequency of the uplink is detected and the spreading code is assigned based on the detected uplink data frequency. If the frequency is high, the spreading bandwidth is reduced, the number of spreading codes is increased, and the number of spreading codes is increased to secure more communication lines, thereby reducing the data collision probability. By increasing the width, it is possible to enhance the noise resistance performance, and it is possible to accurately secure communication resources and the like in response to a change in the frequency of uplink data.

Further, according to the ninth aspect of the present invention, the sixth to sixth aspects are described.
In the invention of the eighth aspect, the control signal for allocating a spreading code to the communication terminal device is spread by using a spreading code different from the spreading code to be allocated to the communication terminal device and transmitted below the downlink noise level. Therefore, it is possible to prevent the spread code from being intercepted, and it is also possible to use it for services requiring confidentiality.

According to the tenth aspect of the present invention, by transmitting a control signal from a communication center apparatus to a communication terminal apparatus, a plurality of communication lines obtained by code division multiplexing with a spread code can transmit data of the same purpose. Since it is used for transmission, when the communication environment is good, each communication line is used to transmit certain data separately, to secure communication capacity, and when the communication environment deteriorates, multiple communication lines are used. Can be used to transmit data for the same purpose, thereby ensuring communication reliability. As a result, communication reliability adapted to the communication environment at that time can be obtained.

According to the eleventh aspect of the present invention, in the first aspect,
In the invention of No. 0, since the same data is transmitted through each of the plurality of communication lines, the receiving side determines the correctness of the received plurality of the same data, for example, by majority decision, thereby improving the reliability of communication. Can be increased.

Further, according to the twelfth aspect, the first aspect
In the invention of No. 0, since the data capable of correcting the error of the certain data is transmitted together with the certain data through a plurality of communication lines, the error of the certain data can be corrected on the receiving side. By performing correction using data, an error correction algorithm can be strengthened, and as a result, communication reliability can be improved.

According to the invention of claim 13, according to claim 1,
In the inventions of Nos. 0 to 12, the noise level of the uplink is detected, and a control signal for transmitting data of the same purpose through the plurality of communication lines is transmitted based on the detected noise level. Therefore, when the noise level is low, each communication line is used for transmitting certain data separately to secure communication capacity, and when the noise level is high, multiple communication lines are used to transmit data for the same purpose. Can be used to ensure communication reliability,
As a result, communication reliability adapted to the noise level at that time can be obtained.

According to the fourteenth aspect of the present invention, the first aspect is provided.
In the inventions of Nos. 0 to 12, the data frequency of the uplink is detected, and a control signal for transmitting data of the same purpose through the plurality of communication lines is transmitted based on the detected uplink data frequency. Therefore, when the frequency of uplink data is high, the data collision probability is reduced by securing communication capacity by using each communication line to transmit certain data separately, and when the frequency of uplink data is low, multiple Communication reliability can be ensured by using a communication line to transmit data for the same purpose, and as a result, communication reliability adapted to the frequency of uplink data at that time can be obtained.

According to the invention of claim 15, according to claim 1,
In the invention of the fourth aspect, the noise level of the uplink is also detected, and the control signal is transmitted based on the detected noise level and the detected uplink data frequency. From both sides, it is possible to determine whether the communication capacity or the reliability of the communication should be ensured, and it is possible to more accurately obtain the reliability of the communication at that time.

Further, according to the sixteenth aspect, the first aspect
In the inventions of (1) to (15), the communication terminal device adds communication terminal device recognition information to a header portion of the communication terminal device and sends the communication data to the up line, and the communication center device sends the sent communication data to the down line. As a result, the communication data transmitted to the downlink is received by the communication terminal device corresponding to the communication terminal device recognition information. For this reason, in all of the above data communication methods according to the present invention, communication between communication terminal devices can be performed.

According to the seventeenth aspect, the sixth aspect is provided.
In the inventions (1) to (16), between the communication center device and the communication terminal device, data communication by the polling method and data communication by the free calling communication method from the communication terminal device to the communication center device are performed by using a spreading code. Code multiplexing allows simultaneous use of services that require data collection efficiency from communication terminal equipment to communication center equipment and services that require high-speed response from communication terminal equipment to communication center equipment Becomes

According to the eighteenth aspect of the present invention, the first aspect
In the invention of the seventh aspect, the communication center device manages the communication frequency of each communication terminal device, performs data communication with the communication terminal device having the managed communication frequency lower than a predetermined value by a polling method, and manages the communication frequency. Since data communication is performed with the communication terminal device higher than the predetermined value by the free calling communication method, a communication response suitable for the service being performed at that time can be obtained for each communication terminal device.

Further, according to the nineteenth aspect, CATV
In the communication center device for the system, a spread signal of spread spectrum modulation in data communication with the communication terminal device is set, and a control signal for causing the communication terminal to set the set spread bandwidth is transmitted to the communication terminal device. Since it was made to transmit, it is possible to set the spreading bandwidth according to changes in the environment in performing data communication,
It is possible to provide a communication center apparatus for a CATV system capable of securing communication resources adapted to a data communication service operated at that time and easily selecting a communication protocol.

According to the twentieth aspect of the present invention, the first aspect is provided.
In the invention of the ninth aspect, the noise level of the uplink is detected,
Since the spread bandwidth is set based on the noise level detected by the noise level detecting means, a communication center apparatus for a CATV system capable of accurately securing communication resources or the like in response to a change in the noise level. Can be provided.

According to the twenty-first aspect, the first aspect is the first aspect.
In the invention of the ninth aspect, the data frequency of the uplink is detected, and the spreading bandwidth is set based on the detected data frequency, so that the communication resources are appropriately secured with respect to the change in the frequency of the uplink data. It is possible to provide a communication center device for a CATV system capable of performing the above.

According to the twenty-second aspect, the CATV
In the system communication center device, the use condition of the frequency in the transmission path is detected, and based on the use condition of the detected frequency, the frequency range of the spread band of the spread spectrum modulation in the data communication with the communication terminal device is set. And a control signal for causing the communication terminal to set the frequency range of the set spreading band to the communication terminal device, so that the CATV system communication center device capable of effectively utilizing frequency resources. Can be provided.

According to the twenty-third aspect, the second aspect is provided.
In the second invention, an uplink noise level is detected,
Since the frequency range of the spread band is set based on the detected noise level and the usage status of the detected frequency, it is possible to more accurately secure communication resources and effectively use frequency resources. A communication center device for a CATV system capable of performing the above can be provided.

According to the invention of claim 24, CATV
In the system communication center device, a spread code of spread spectrum modulation in data communication with the communication terminal device is set for each communication terminal, and a control signal for causing the communication terminal to set the set spread code is transmitted. Since transmission is performed to each communication terminal device, when performing frequency division multiplexing, it is possible to easily secure communication resources and select a communication protocol suitable for the data communication service currently being operated. A communication center device for a CATV system can be provided.

According to the invention of claim 25, claim 2
In the invention of the fourth aspect, the noise level of the uplink is detected,
Since the spreading code is set based on the detected noise level, it is possible to provide a communication center apparatus for a CATV system capable of accurately securing communication resources and the like in response to a change in the noise level. .

According to the twenty-sixth aspect, the second aspect is provided.
According to the fourth aspect of the present invention, since the uplink data frequency is detected and the spreading code is set based on the detected data frequency, it is possible to appropriately secure communication resources and the like in response to a change in the uplink data frequency. A communication center device for a CATV system capable of performing the above can be provided.

According to the twenty-seventh aspect, the second aspect is provided.
In the inventions of Nos. 4 to 26, the control signal is spread by using a spreading code different from a spreading code set in the communication terminal device and transmitted to a level lower than a downlink noise level, so that confidentiality is maintained. A communication center apparatus for a CATV system that can be used for required services can be provided.

According to the twenty-eighth aspect of the present invention, CATV
In a system communication center device, a plurality of communication lines obtained by code division multiplexing with a spreading code are used to transmit data of the same purpose, and in that case, a communication terminal is used to operate the same communication line on a plurality of communication lines. Since a control signal for transmitting / receiving target data is transmitted to a corresponding communication terminal device, a communication center device for a CATV system capable of obtaining communication reliability adapted to a communication environment at that time is provided. can do.

According to the invention of claim 29, claim 2
In the invention of claim 8, it is possible to transmit data of the same purpose to the corresponding communication terminal device through each of the plurality of communication lines, and determine whether the same data received through the plurality of communication lines is correct or not by majority decision. Because
A communication center device for a CATV system capable of improving the reliability of communication can be provided.

According to the thirtieth aspect, the second aspect is provided.
In the invention of the eighth aspect, together with certain data, data capable of correcting an error of the certain data is transmitted to a corresponding communication terminal device through a plurality of communication lines, and an error of the received certain data is replaced with the received error. The present invention provides a communication center apparatus for a CATV system capable of correcting errors by using correctable data, thereby enhancing an error correction algorithm and, as a result, improving communication reliability. be able to.

According to the invention of claim 31, according to claim 2,
In the inventions of 8 to 30, the noise level of the uplink is detected, and the control signal for transmitting the same data through the plurality of communication lines is transmitted based on the detected noise level. Therefore, it is possible to provide a CATV system communication center device capable of obtaining communication reliability adapted to the noise level at that time.

Further, according to the invention of claim 32, claim 2
In the inventions of 8 to 30, the data frequency of the uplink is detected, and a control signal for transmitting the same data through the plurality of communication lines is transmitted based on the detected data frequency. Therefore, it is possible to provide a CATV system communication center apparatus capable of obtaining communication reliability adapted to the uplink data frequency at that time.

According to the invention of claim 33, claim 3
In the invention of the second aspect, since the noise level of the uplink is also detected, and the control signal is transmitted based on the detected noise level and the detected data frequency,
It is possible to provide a CATV system communication center device that can more reliably obtain communication reliability at that time.

Further, according to the invention of claim 34, claim 1
In the inventions of Nos. 9 to 33, when the communication data in which the communication terminal device recognition information is added to the header portion via the uplink is received, the received communication data is transmitted to the downlink. The transmitted communication data can be received by the communication terminal device corresponding to the communication terminal device recognition information, and a communication center device for a CATV system that enables communication between the communication terminal devices can be provided.

According to the invention of claim 35, CATV
In a system communication terminal device, a control signal for setting a spread bandwidth of spread spectrum modulation in data communication with a communication center device is received, and a spread bandwidth is set based on the received control signal. Therefore, it is possible to set the spreading bandwidth according to changes in the environment in performing data communication, to secure communication resources adapted to the data communication service currently being operated,
And C that allows easy selection of communication protocol
A communication terminal device for an ATV system can be provided.

According to the thirty-sixth aspect, CATV
In the system communication terminal device, a control signal for setting a frequency range of a spread band of spread spectrum modulation in data communication with a communication center device is received, and a frequency range of the spread band is set based on the received control signal. Is set, it is possible to provide a CATV system communication terminal device that can effectively use frequency resources.

According to the thirty-seventh aspect, CATV
In the system communication terminal device, a control signal for setting a spread code of spread spectrum modulation in data communication with a communication center device is received, and the spread code is set based on the received control signal. Therefore, when performing frequency division multiplexing, securing communication resources adapted to the data communication service currently being operated,
And C that allows easy selection of communication protocol
A communication terminal device for an ATV system can be provided.

According to the thirty-eighth aspect of the present invention, the CATV
In the system communication terminal device, receiving a control signal for transmitting and receiving data of the same purpose over a plurality of communication lines,
Based on the received control signal, a plurality of communication lines obtained by code division multiplexing with a spreading code are used to transmit data of the same purpose, so that communication of the communication environment adapted to the communication environment at that time is used. A communication terminal device for a CATV system capable of obtaining reliability can be provided.

According to the invention of claim 39, claim 3
In the invention of the eighth aspect, data of the same purpose is transmitted to the communication center device through each of the plurality of communication lines, and the validity of the same data received through the plurality of communication lines can be determined by majority decision. Thus, it is possible to provide a communication terminal device for a CATV system capable of improving communication reliability.

According to the invention of claim 40, claim 3
In the invention according to the eighth aspect, it is possible to transmit, together with certain data, data capable of correcting an error of the certain data to a communication center device through a plurality of communication lines, It is possible to provide a communication terminal device for a CATV system capable of enhancing an error correction algorithm, thereby improving the reliability of communication. it can.

Further, according to the invention of claim 41, claim 3
In the inventions of claims 5 to 40, the communication data is transmitted to the communication center device by adding the communication terminal device recognition information to its header portion, and the communication data addressed to itself is transmitted based on the communication terminal device recognition information added to the header portion. CATV system that can communicate with communication terminal devices by using the communication data received through the uplink and the communication center device that sends the communication data to the downlink. Communication terminal device can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overview of a CATV system communication center device and a CATV system using a CATV system communication terminal device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing details of a configuration of a center shown in FIG. 1;

FIG. 3 is a block diagram illustrating details of a configuration of a terminal in FIG. 1;

FIG. 4 is a diagram showing a format of a packet of communication data according to the first embodiment of the present invention, showing a data packet (FIG. 4 (a)) and a diagram showing a setting command (FIG. 4 (b)). ).

FIG. 5 is a schematic diagram showing a method of dynamically setting a spreading code and a spreading bandwidth according to Embodiment 1 of the present invention, showing a case where the spreading code is set to be small and the spreading bandwidth is set to be large ( FIG. 5 (a)) and a diagram (FIG. 5 (b)) showing a case where the number of spreading codes is large and the spreading bandwidth is set small.

FIG. 6 is a schematic diagram showing a usage form of a communication line when a plurality of communication lines obtained by the code division multiplexing are used to transmit different target data when performing code division multiplexing in the same frequency band. It is.

FIG. 7 is a schematic diagram showing a use form of communication lines when a plurality of communication lines obtained by code division multiplexing are used for transmitting data of the same purpose.

FIG. 8 is a schematic diagram showing an example of another usage form of a communication line when a plurality of communication lines obtained by code division multiplexing are used for transmitting data of the same purpose.

FIG. 9 is a schematic diagram showing a method of dynamically setting a spreading bandwidth when performing code division multiplexing, and showing a case where a large number of communication lines are secured by setting a small spreading bandwidth.
(a)) and FIG. 9 (b) showing the case where the number of communication lines is reduced and the spreading bandwidth is set large to ensure the reliability of the communication lines.

[Explanation of symbols]

 ad to spreading code Bdo occupied band Bd1 to Bd8 unit occupied band Cr center L1 to L4 communication line Tl1 to Tln terminal 1 transmission line 2 TV 3 remote controller 4,24 communication control unit 5,25 SS transmission unit 6,26 SS reception Unit 7, 27 Transmission data 7, 8, 28 Reception data 9, 29 Spread band control signal 10 Noise level detection unit 11 Data packet 12 Setting command 21 Data frequency detection unit 22 Frequency usage status detection unit

Claims (41)

[Claims] 1. Data for performing data communication between a communication center device and one or more communication terminal devices connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spreading code. In the communication method, a control signal is transmitted from the communication center device to the communication terminal device, thereby dynamically setting a spread bandwidth of spread spectrum modulation in the data communication, wherein the data is transmitted using a CATV system. Communication method. 2. The data communication method using a CATV system according to claim 1, wherein the communication center device detects a noise level of an uplink which is a communication line from the communication terminal device to the communication center device. A data communication method using a CATV system, wherein the spreading bandwidth is set based on the detected noise level. 3. The data communication method using a CATV system according to claim 1, wherein the communication center device detects a data frequency of an uplink which is a communication line from the communication terminal device to the communication center device, A data communication method using a CATV system, wherein the spreading bandwidth is set based on the detected data frequency. 4. Data for performing data communication between a communication center device and one or more communication terminal devices connected by a transmission path of a CATV system using spread spectrum modulation for performing code modulation and demodulation with a spread code. In the communication method, spread of spectrum spread modulation in the data communication is performed by detecting a use state of a frequency in the transmission path in the communication center device and transmitting a control signal from the communication center device to the communication terminal device. A data communication method using a CATV system, wherein a frequency range of a band is dynamically set based on a usage state of the detected frequency. 5. The data communication method using a CATV system according to claim 4, wherein the communication center device also detects a noise level of an uplink which is a communication line from the communication terminal device to the communication center device. A data communication method using a CATV system, wherein a frequency range of the spread band is set based on the detected noise level and the use state of the detected frequency. 6. Data for performing data communication between a communication center device and one or more communication terminal devices connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spreading code. In a communication method, a CATV system is characterized in that a control signal is transmitted from the communication center device to the communication terminal device to dynamically assign the spreading code to the one or more communication terminal devices. The data communication method used. 7. The data communication method using a CATV system according to claim 6, wherein the communication center device detects a noise level of an uplink which is a communication line from the communication terminal device to the communication center device. A data communication method using a CATV system, wherein the spreading code is assigned based on the detected noise level. 8. The data communication method using a CATV system according to claim 6, wherein the communication center device detects the data frequency of the uplink, and allocates the spreading code based on the detected data frequency. A data communication method using a CATV system, characterized in that: 9. The data communication method using a CATV system according to claim 6, wherein the control signal is transmitted from the communication center device using a spreading code different from a spreading code assigned to the communication terminal device. CA that spreads below a noise level of a downlink which is a communication line toward a communication terminal device and transmits the same.
A data communication method using a TV system. 10. Data for performing data communication between a communication center device and one or more communication terminal devices connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spreading code. In the communication method, by transmitting a control signal from the communication center device to the communication terminal device, a plurality of communication lines that are code-divided by the spreading code and formed multiplexed in the same frequency band of the same transmission line are transmitted. A data communication method using a CATV system, wherein the data communication method is used to transmit data of the same purpose. 11. The data communication method using a CATV system according to claim 10, wherein the same data is transmitted through each of the plurality of communication lines. 12. A data communication method using a CATV system according to claim 10, wherein data capable of correcting an error of the certain data is transmitted together with the certain data through the plurality of communication lines. A data communication method using a CATV system. 13. A data communication method using a CATV system according to claim 10, wherein said communication center device detects a noise level of an uplink which is a communication line from said communication terminal device to said communication center device. And transmitting the control signal based on the detected noise level. 14. A data communication method using a CATV system according to claim 10, wherein said communication center device detects data frequency of an uplink which is a communication line from said communication terminal device to said communication center device. And transmitting the control signal based on the detected data frequency. 15. The data communication method using a CATV system according to claim 14, wherein the communication center device also detects the noise level of the uplink, and determines the detected noise level and the detected data frequency. Transmitting the control signal based on the CAT
A data communication method using a V system. 16. A data communication method using a CATV system according to claim 1, wherein said communication terminal device adds communication terminal device recognition information to a header portion of said communication data, and said communication center device. Using the CATV system, wherein the communication center device transmits the transmitted communication data to a downstream line, which is a communication line toward the communication terminal device. Data communication method. 17. The data communication method using a CATV system according to claim 6, wherein data communication based on a polling method is performed between said communication center apparatus and said communication terminal apparatus, and said communication is performed from said communication terminal apparatus. A data communication method using a CATV system, characterized by code-multiplexing data communication with a center device by a free call communication method using the spreading code. 18. The data communication method using a CATV system according to claim 17, wherein the communication center device manages a communication frequency for each of the communication terminal devices, and the communication frequency managed is lower than a predetermined value. Data communication using a CATV system, wherein data communication is performed with a terminal device by a polling method, and data communication is performed by a free call communication method with a communication terminal device whose communication frequency to be managed is higher than the predetermined value. Method. 19. A communication center apparatus for performing data communication with one or more communication terminal apparatuses connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spreading code, A spread bandwidth setting means for setting a spread bandwidth of spread spectrum modulation in the data communication; and a control signal for causing the communication terminal to set the spread bandwidth set by the spread bandwidth setting means to the communication terminal. A communication center apparatus for a CATV system, comprising: a control signal transmitting means for transmitting to a communication terminal apparatus. 20. The communication center apparatus for a CATV system according to claim 19, further comprising: a noise level detecting unit configured to detect a noise level of an uplink which is a communication line from the communication terminal apparatus to the communication center apparatus. The communication center apparatus for a CATV system, wherein the spread bandwidth setting means sets the spread bandwidth based on a noise level detected by the noise level detection means. 21. The communication center apparatus for a CATV system according to claim 19, further comprising: a data frequency detecting unit that detects a data frequency of an uplink which is a communication line from the communication terminal apparatus to the communication center apparatus. The communication center apparatus for a CATV system, wherein the spread bandwidth setting means sets the spread bandwidth based on the data frequency detected by the data frequency detection means. 22. A communication center apparatus for performing data communication with one or more communication terminal apparatuses connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spreading code, A frequency band use condition detecting means for detecting a use condition of the frequency in the transmission path; and a frequency range of a spread band of the spread spectrum modulation in the data communication based on the use condition of the frequency detected by the frequency band use condition detect device And a control for transmitting, to the one or more communication terminal devices, a control signal for setting the communication terminal to set the frequency range of the spread band set by the spread band frequency range setting device. A communication center apparatus for a CATV system, comprising: signal transmission means. 23. The communication center device for a CATV system according to claim 22, further comprising a noise level detecting means for detecting a noise level of an uplink which is a communication line from the communication terminal device to the communication center device. The spread band frequency range setting means, based on the noise level detected by the noise level detection means and the use status of the frequency detected by the frequency band use status detection means,
A communication center apparatus for a CATV system, wherein a frequency range of the spread band is set. 24. A communication center apparatus for performing data communication with one or more communication terminal apparatuses connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spreading code, A spreading code setting unit for setting the spreading code for each of the communication terminals, and a control signal for causing the communication terminal to set the spreading code set by the spreading code setting unit to each of the communication terminal devices. A communication center apparatus for a CATV system, comprising: a control signal transmitting unit. 25. The CATV system communication center device according to claim 24, further comprising: a noise level detecting unit that detects a noise level of an uplink which is a communication line from the communication terminal device to the communication center device. The communication center apparatus for a CATV system, wherein the spreading code setting means sets the spreading code based on a noise level detected by the noise level detecting means. 26. The communication center device for a CATV system according to claim 24, further comprising: a data frequency detecting unit configured to detect a data frequency of an uplink which is a communication line from the communication terminal device to the communication center device. The communication center apparatus for a CATV system, wherein the spreading code setting means sets the spreading code based on the data frequency detected by the data frequency detecting means. 27. A communication center apparatus for a CATV system according to claim 24, wherein said control signal transmitting means uses a spreading code different from a spreading code set in said communication terminal apparatus for said control signal. ,
A communication center device for a CATV system, wherein the communication center device spreads the noise to a level equal to or lower than a noise level of a downlink which is a communication line from the communication center device to the communication terminal device. 28. A communication center apparatus for performing data communication with one or more communication terminal apparatuses connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spreading code, Communication control means for using a plurality of communication lines that are code-divided by the spread code and multiplexed in the same frequency band of the same transmission line to transmit and receive data of the same purpose to and from any of the communication terminal devices When the plurality of communication lines are used for transmitting and receiving data of the same purpose, a control signal for causing the communication terminal to transmit and receive data of the same purpose over the plurality of communication lines is transmitted to the plurality of communication lines. CAT comprising control signal transmitting means for transmitting to a communication terminal device corresponding to a line.
Communication center device for V system. 29. The CATV system communication center device according to claim 28, wherein said communication control means transmits the same data to a communication terminal device corresponding to said plurality of communication lines through each of said plurality of communication lines. A communication center apparatus for a CATV system, which can determine, by majority decision, whether the same data is transmitted and received through said plurality of communication lines. 30. A communication center apparatus for a CATV system according to claim 28, wherein said communication control means transmits, through said plurality of communication lines, data capable of correcting an error of said certain data together with certain data. For certain data transmitted to the communication terminal devices corresponding to the plurality of communication lines and received through the plurality of communication lines, and for the data capable of correcting the error of the certain data, the error of the certain data is A communication center apparatus for a CATV system, wherein the communication center apparatus can correct the error using data that can correct the error. 31. The communication center apparatus for a CATV system according to claim 28, further comprising a noise level detecting means for detecting a noise level of an uplink which is a communication line from said communication terminal apparatus to said communication center apparatus. The control signal transmitting means transmits the control signal based on the noise level detected by the noise level detecting means. 32. The communication center apparatus for a CATV system according to claim 28, further comprising a data frequency detecting means for detecting a data frequency of an uplink which is a communication line from said communication terminal apparatus to said communication center apparatus. A communication center apparatus for a CATV system, wherein the control signal transmitting means transmits the control signal based on the data frequency detected by the data frequency detecting means. 33. The communication center apparatus for a CATV system according to claim 32, further comprising: a noise level detecting means for detecting the noise level of the uplink, wherein the control signal transmitting means detects the noise level by the noise level detecting means. And transmitting the control signal based on the detected noise level and the data frequency detected by the data frequency detecting means. 34. The communication center apparatus for a CATV system according to claim 19, wherein communication terminal apparatus recognition information is added to a header portion through an uplink which is a communication line from said communication terminal apparatus to said communication center apparatus. A communication center for a CATV system, wherein the communication center transmits the received communication data to a downlink which is a communication line from the communication center device to the communication terminal device. apparatus. 35. A communication terminal device for performing data communication with a communication center device connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spread code, Control signal receiving means for receiving a control signal for setting a spread bandwidth of spread spectrum modulation in the data communication transmitted from the device; and the spread band based on the control signal received by the control signal receiving means. A communication terminal device for a CATV system, comprising: a spread bandwidth setting means for setting a width. 36. A communication terminal device for performing data communication with a communication center device connected through a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spread code, Control signal receiving means for transmitting a control signal for setting a frequency range of a spread band of spread spectrum modulation in the data communication transmitted from the device, based on the control signal received by the control signal receiving means, A communication terminal device for a CATV system, comprising: a spread band frequency range setting means for setting a frequency range of a spread band. 37. A communication terminal device for performing data communication with a communication center device connected through a transmission path of a CATV system by using spread spectrum modulation for performing coding modulation and demodulation with a spreading code, Control signal receiving means for receiving a control signal for setting a spread code of spread spectrum modulation in the data communication transmitted from the device, and setting the spread code based on the control signal received by the control signal receiving means A communication terminal device for a CATV system, comprising: 38. A communication terminal device for performing data communication with a communication center device connected by a transmission path of a CATV system using spread spectrum modulation for performing coding modulation and demodulation with a spreading code, Control signal receiving means for receiving a control signal for transmitting and receiving the same object data over a plurality of communication lines, transmitted from the device, and a code with the spread code based on the control signal received by the control signal receiving means. A communication terminal device for a CATV system, comprising: communication control means for using a plurality of communication lines divided and multiplexed in the same frequency band on the same transmission line to transmit and receive data for the same purpose. . 39. The communication terminal device for a CATV system according to claim 38, wherein the communication control means transmits the same data to the communication center device through each of the plurality of communication lines, and A communication terminal device for a CATV system, wherein the right or wrong of the same data received through a communication line can be determined by majority decision. 40. The communication terminal device for a CATV system according to claim 38, wherein said communication control means transmits, through said plurality of communication lines, data capable of correcting an error of said certain data together with certain data. For certain data transmitted to the communication center apparatus and received through the plurality of communication lines, and for data capable of correcting an error of the certain data, the error of the certain data can be corrected for the error of the certain data. A communication terminal device for a CATV system, which can be corrected using possible data. 41. The communication terminal device for a CATV system according to claim 35, wherein communication data is transmitted to said communication center device by adding communication terminal device recognition information to a header portion thereof, and said header portion is transmitted to said communication center device. A communication terminal device for a CATV system, characterized in that it is configured to be able to determine and receive communication data addressed to itself based on the added communication terminal device recognition information.