JP2003032656A - Method for reusing catv facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for reusing a CATV facility capable of reusing an already set CATV facility. SOLUTION: The connecting part of a CATV coaxial cable 14 connected to the input terminal of an amplifier is connected to the output terminal of the amplifier, and the connecting part of the CATV coaxial cable 14 connected to the output terminal of the amplifier is connected to the input terminal of the amplifier. This cable re-connecting work is rendered to amplifiers 121 -12n set at the unnecessary CATV coaxial cables 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of reusing CATV equipment for reusing existing equipment used in CATV.

[0002]

2. Description of the Related Art CATVs (cable televisions) are used to eliminate inferior viewing when it is difficult to view television by radio waves due to circumstances such as surrounding buildings and terrain. In CATV, a CATV center that transmits TV signals for TV broadcasting is connected to a CATV subscriber's house that receives broadcasting by a coaxial cable. Further, in order to compensate for the attenuation when the television signal is transmitted through the coaxial cable, amplifiers and the like are installed in the coaxial cable at regular intervals.

As described above, the CATV network in which coaxial cables are stretched around has spread in urban areas and mountain areas, and has eliminated radio wave interference.

[0004]

By the way, some CATVs provide various services such as Internet service in addition to the elimination of radio interference. C like this
In order to cope with the diversification of ATVs, CATVs that provide various services using optical fiber cables that enable broadband and high-speed communication have begun to replace CATVs that use conventional coaxial cables.

When an optical fiber cable is used for CATV, it is necessary to remove conventional equipment such as coaxial cable and amplifier. As a result, when laying an optical fiber cable, there arises a problem that a large amount of coaxial cables, amplifiers, and the like become waste.

An object of the present invention is to provide a method for reusing CATV equipment which solves the above-mentioned problems and enables the reuse of existing CATV equipment.

[0007]

According to the invention of claim 1, CA
This is a method of reusing TV equipment.
A CATV coaxial cable installed up to the ATV subscriber, and an amplifier installed in the CATV coaxial cable at intervals to compensate for attenuation of a signal transmitted through the CATV coaxial cable. CA equipped
A method of reusing CATV coaxial cables and amplifiers that are no longer needed in a TV network, wherein CATV coaxial cables connected to input terminals of the amplifiers are connected. Part to the output terminal of the amplifier, and the cable reconnection work for connecting the connection part of the CATV coaxial cable connected to the output terminal of the amplifier to the input terminal of the amplifier, It is characterized in that it is performed for the amplifier installed in the CATV coaxial cable.

The invention of claim 2 is the CA according to claim 1.
In the method for reusing the equipment for TV, the cable reconnection work is performed on an amplifier installed between the CATV center and the CATV subscriber. The invention of claim 3 is the CATV according to claim 2.
In the method of reusing equipment for cable, the CATV coaxial cable used by the CATV subscriber is connected to the CATV coaxial cable that has completed the cable reconnection work by a mixer, and the CATV subscriber uses the CATV coaxial cable. I was doing CA
The CATV center receives a signal from the device after performing a device connection work for connecting a device to the TV coaxial cable and ending the cable reconnection work and the device connection work.

The invention of claim 4 is the CA according to claim 3.
In the method of reusing TV equipment, the device is a TV camera. The invention of claim 5 is the method for reusing CATV equipment according to claim 3, wherein the device is a computer.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described in detail with reference to the drawings. In this embodiment, for example, a case where a CATV network facility 1 (hereinafter referred to as CATV facility 1) as shown in FIG. 1 is reused will be described.

In the CATV network of FIG. 1, the CATV center 2
, M CATV subscriber homes 3 (m: natural number)₁~ 3_m
To a TV signal using the CATV equipment 1
It That is, the television signal is transmitted in the downstream direction. CA
The TV center 2 has a broadcasting device for transmitting a television signal.
A vessel 21 is provided. Also, CATV subscriber's home 3 ₁
~ 3_mThen, the TV signal from CATV Center 2
Vision 3₁₁~ 3_{1 m}To receive each. C in FIG.
In the ATV network, CATV subscriber home 3₁~ 3_mTo CAT
Communication to V center 2, that is, signal transmission in the up direction
It is also possible to do so. This CATV network supports two-way communication
It is a system that enables it.

The CATV equipment 1 is equipped with wires 11 stretched between a large number of utility poles 101. Wire 11 has n
The number (n: natural number) of the main amplifiers 12 _{1 to} 12 _n and the branch amplifier 13 are installed at intervals. That is,
The main line amplifiers 12 _{1 to} 12 _n are installed between the CATV center 2 and the branch amplifier 13. The branch amplifier 13 is attached to the CATV subscriber homes 3 _{1 to} 3 _m . Between the broadcast equipment 21 and the trunk amplifier 12 ₁ of the CATV center 2, while the trunk amplifier ₁₂ 1 to 12 _n, and between the trunk amplifier 12 _n and the branch amplifier 13, coaxial cable 14 is stretched. Furthermore, the branch amplifier 13
The coaxial cable 14 is stretched between the CATV subscriber homes 3 _{1 to} 3 _m .

[0013] trunk amplifier 12 ₁ is installed as shown in FIG. That is, the main amplifier 12 is the clamp 1
It is fixed to the wire ₁₁ by 21 1. The IN terminal on the input side of the main line amplifier 12 ₁ is connected to the CATV center 2 side via the coaxial cable 14, and the OUT terminal on the output side via the coaxial cable 14 the main line amplifier 12 ₂ which is the next amplifier. It is connected to the.

[0014] The outline of the trunk amplifier 12 ₁ shown in FIG. Trunk amplifier 12 ₁ includes a high-pass filter 12A, 12C,
The down amplifier 12B, the low pass filters 12D and 12F, and the up amplifier 12E are provided. The high pass filter 12A and the low-pass filter 12F, is connected to the connection portion of the CATV center 2 side of the coaxial cable 14, and the high-pass filter 12C and the low-pass filter 12D, is connected to the connection portion of the trunk amplifier 12 ₂ of the coaxial cable 14 There is. High-pass filter 12A and high-pass filter 12C
The downstream amplifier 12B is connected between the low-pass filter 12D and the low-pass filter 12D, and the upstream amplifier 12E is connected between the low-pass filter 12D and the low-pass filter 12F.

High-pass filter 12A and downstream amplifier 12
B and the high-pass filter 12C configure a downstream amplification circuit, and the low-pass filter 12D, the upstream amplifier 12E, and the low-pass filter 12F configure an upstream amplification circuit.

The down-side amplification circuit amplifies the television signal transmitted from the CATV center 2 to the CATV subscriber homes 3 _{1 to} 3 _m . In other words, the high-pass filters 12A and 12C of the downstream side amplifier circuit have a wide band of 70 to 770 MHz shown in FIG. 4, and the downstream amplifier 12B amplifies the television signal transmitted in this wide band. In CATV, since a band of 6 MHz is usually provided for one channel, the downstream amplification circuit amplifies and transmits the television signal of 113 channels.

The amplifier circuit on the upstream side is the CATV subscriber's home 3
_The signal transmitted from _{1 to} 3 _m to the CATV center 2 is amplified. That is, the low-pass filter 1 of the upstream amplification circuit
2D and 12F have a narrow band of 10 to 55 MHz, and the upstream amplifier 12E amplifies the signal transmitted in this narrow band.

Main line amplifier 12_Two~ 12_nIs the main amplifier 1
Two₁Since these are the same as those in the above, their description will be omitted. Branch
The amplifier 13 is input via the coaxial cable 14.
Main line amplifier 12_nAmplifies and branches the TV signal from
CATV subscriber home 3₁~ 3 _mCoaxial connected to
The branched signals are sent to the cable 14, respectively.

In such a state, the CATV using the coaxial cable 14 transmits the television signal from the broadcasting device 21 of the CATV center 2 to the CATV subscriber homes 3 _{1 to} 3 _m in a wide band. Further, the signals from the CATV subscriber homes 3 _{1 to} 3 _m are transmitted to the CATV center 2 in a narrow band.

By the way, CA using the coaxial cable 14
When the TV network is a CATV network using an optical fiber cable, main line amplifiers 12 _{1 to} 12 _{n of} the CATV equipment 1,
The coaxial cable 14 and the branch amplifier 13 become unnecessary.

Therefore, as shown in FIG. 5, the clamp 12
₁₁Main line amplifier 12 fixed to wire 11 by
₁Is left as it is. And the CATV installation
Perform cable reconnection work for equipment 1. That is, the main line
Amplifier 12₁Disconnect the coaxial cable 14 to.
After this, the trunk amplifier 12₁Was connected to the IN terminal of
Reconnect the connection of the coaxial cable 14 to the OUT terminal, and
Connect the connection part of the coaxial cable 14 that was connected to the UT terminal.
Reconnect to IN terminal. Specifically, the clamp 12 ₁₁
Remove the main line amplifier 12₁Rotate 180 degrees to
P 12₁₁Reconnect to. As a result, the main amplifier 1
Two₁The IN terminal and the OUT terminal of the
Cable reconnection work becomes easy. Reconnect this cable
Work on the main amplifier 12_Two~ 12_nAlso to.

Further, as shown in FIG. 6, the branch amplifier 1
3 is removed and the mixing amplifier 15 is connected. The mixing amplifier 15 mixes the signals transmitted through the plurality of coaxial cables 14 and outputs the mixed signals to one coaxial cable 14.

By such cable reconnection work,
When a signal is input to the coaxial cable 14 connected to the CATV subscriber's homes 3 _{1 to} 3 _m , this signal is ready to be transmitted to the CATV center 2 side.

After this, the device connection work is performed. That is, C
At the ATV center 2, the CATV equipment 1 whose reconnection has been completed
The device 22 according to the service provided by using the
It is used instead of the container 21. For example, as shown in Figure 6.
In CATV subscriber's home 3₁~ 3 _mThe same side used
Connect the TV camera 51 to the connection part of the cable 14,
When performing monitoring work, the device 22 of the CATV center 2
Is the receiving device. In addition, as shown in FIG.
Subscriber house 3₁~ 3_mSide used coaxial cable 14
Information service by connecting the computer 52 to the connection part of
In this case, the device 22 becomes the host computer.
It Furthermore, the branch amplifier 13 is used on the CATV center 2 side.
The TV signal and the computer data.
If so, it is possible to use it in combination with FIG. 6 and FIG. 7.
is there.

Thus, the coaxial cable 1 of the CATV network
If 4 is changed to an optical fiber cable, trunk amplifier 1
CA no longer needed after reconnecting 2 _{1 to} 12 _n
It is possible to form a new communication system for enabling reuse of the TV equipment 1. At this time, since signals are transmitted to the CATV center 2 side in a wide band of 70 to 770 MHz, p (p: natural number) television cameras 5 _{1 to} 5
It becomes possible to send multi-channel signals from the _p or q (q: natural number) computers 6 _{1 to} 6 _q to the CATV center 2. That is, it is possible to form a communication system that performs upstream communication in a wide band. If control of the TV cameras 5 _{1 to} 5 _p is required, 10 to 55 MHz
Of the television camera 5 ₁ to the signal using the narrow band of
It is also possible to manipulate 5 _p .

As described above, the unnecessary CATV network that performs broadband communication in the downlink direction and narrow band in the uplink direction is reused as a communication system that performs communication in the broadband direction in the uplink direction and the bandwidth in the downlink direction. It will be possible.

Although the embodiment of the present invention has been described in detail above, the specific configuration is not limited to this embodiment, and there are design changes and the like within the scope not departing from the gist of the present invention. Also included in the present invention. For example, in this embodiment, the downlink frequency band is 70 to 770 MHz. In addition to this frequency band, various bands such as 7
0-220MHz, 70-350MHz, 70-450MHz,
There are bands such as 70 to 550 MHz, and the present invention is also applicable to CATV networks having these bands.

In the device connection work, the TV cameras 5 _{1 to} 5
_{Although p} and the computers 6 _{1 to} 6 _q are used, a device or the like for detecting a human body using various sensors may be used. In addition, not all of the coaxial cable 14 on the CATV subscriber's home side but a part thereof may be used to form a communication system by reusing the CATV facility 1.

In this embodiment, the main amplifier 12 is used._nOr
CATV network for branching these television signals by the branch amplifier 13
The present invention was applied to
There are various types. For example, as shown in FIG.
Main line amplifier 12_kTrunk TV signal from (1 <k <n)
It is branched by the line branch amplifier 16, and the main line amplifier 12 at the subsequent stage is branched.
_{k + 1}This invention is applied to the CATV networks added to
Is applicable. In this case, as shown in FIG.
Use the mainline mixing amplifier 17 instead of the mainline branch amplifier 16.
And form a new communication system.

Further, the present invention can be applied to a CATV network for branching a television signal by connecting a distributor 18 to the latter stage of the main amplifier or the latter stage of the branch amplifier 13 as shown in FIG. is there. In this case, as shown in FIG. 11, a mixer 19 is used instead of the distributor 18 to form a new communication system. Furthermore, the present invention can be applied to a CATV network that also uses the branching forms of FIGS. 8 and 10.

[0031]

As described above, according to the present invention, an unnecessary CATV facility can be reused for transmitting a signal for upstream. Also, CAT
When cable reconnection work is performed on the amplifier installed between the V-center and the CATV subscriber's house, CATV
The CATV equipment that has become unnecessary can be reused as a communication system in which the center provides a new service. In particular, since the frequency band for sending from the CATV center side to the CATV subscriber's home side is wide, it is possible to send multi-channel signals to the CATV center side using this wide band.

If a large number of television cameras and computers are used as the equipment, it becomes possible for the CATV center side to provide services using these television cameras and computers.

[Brief description of drawings]

FIG. 1 is an explanatory diagram for explaining a CATV network used in an embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining how to install a main line amplifier.

FIG. 3 is a block diagram showing a schematic configuration of a main line amplifier.

FIG. 4 is a diagram showing bands of the CATV network of FIG.

5 is an explanatory diagram for explaining a cable reconnection work in the CATV facility of FIG. 1. FIG.

FIG. 6 is an explanatory diagram for explaining reuse of the CATV facility of FIG. 1.

7 is an explanatory diagram for explaining another reuse of the CATV facility of FIG. 1. FIG.

FIG. 8 is an explanatory diagram illustrating another example of a CATV network.

9 is an explanatory diagram for explaining a cable reconnection work for the CATV network of FIG. 8;

FIG. 10 is an explanatory diagram illustrating another example of a CATV network.

11 is an explanatory diagram for explaining a cable reconnection operation for the CATV network of FIG.

[Description of Reference Signs] 1 CATV facility 1A CATV facility 2 CATV center 3 _{1 to} 3 _m CATV subscriber home 3 _{11 to} 3 _{1 m} Television 5 _{1 to} 5 _p Television camera 6 _{1 to} 6 _q Computer 11 Wire 12 _{1 to} 12 _n Main line amplifier 12 ₁₁ Clamps 12A, 12C High pass filter 12B Down line amplifier 12D, 12F Low pass filter 12E Up line amplifier 13 Branch amplifier 14 Coaxial cable 15 Mixing amplifier 16 Main line branch amplifier 17 Main line mixing amplifier 18 Distributor 19 Mixer 21 Broadcast equipment 22 Equipment

Claims (5)

[Claims] 1. A CATV coaxial cable (14) installed between a CATV center (2) and a CATV subscriber, and to compensate for attenuation of a signal transmitted through the CATV coaxial cable (14), CA at intervals
In a CATV network equipped with amplifiers (12 _{1 to} 12 _n ) installed on a TV coaxial cable (14),
A CAT that reuses the CATV coaxial cable (14) and the amplifier (12 _{1 to} 12 _n ) that are no longer needed
A method for recycling facilities for V, the amplifier ₍₁₂ 1 -
12 _n ) CATV connected to the input terminal (IN)
The connection portion of the coaxial cable (14) for use with the amplifier (12
Connect to ₁ to 12 _n) of the output terminal (OUT), and a connecting portion of the amplifier ₍₁₂ 1 to 12 _n) coaxial cable CATV connected to the output terminal (OUT) of (14), wherein Input terminal (IN) of the amplifier (12 _{1 to} 12 _n )
The cable reconnection work to connect to
CA, which is performed for the amplifiers (12 _{1 to} 12 _n ) installed in the ATV coaxial cable (14).
How to reuse TV equipment. 2. The cable reconnection work is performed by the CAT.
The method for reusing CATV equipment according to claim 1, wherein the operation is performed for an amplifier (12 _{1 to} 12 _n ) installed between a V center (2) and the CATV subscriber. 3. A CAT that has completed the cable reconnection work.
The CATV coaxial cable (14) used by the CATV subscriber is connected to the V coaxial cable (14) with a mixer, and the CATV used by the CATV subscriber is connected.
After the device connection work for connecting the device (22) to the TV coaxial cable (14) is performed and the cable reconnection work and the device connection work are completed, the CATV center (2) sends the device (22) from the device (22). The method for reusing CATV equipment according to claim 2, wherein a signal is received. 4. The method for reusing CATV equipment according to claim 3, wherein the device (22) is a television camera. 5. The method for reusing CATV equipment according to claim 3, wherein the device (22) is a computer.