JP5461021B2 - Optical transmission system and optical terminal device - Google Patents

Description

  The present invention is an optical transmission capable of transmitting an optical television signal from a center device to an optical terminal device via an optical transmission line and performing communication between the center device and the optical terminal device via an optical transmission line. The present invention relates to a system and an optical terminal device thereof.

  A so-called optical CATV may be configured using the above optical transmission system. In this case, the optical terminal device is installed in each home, and the optical control signal is transmitted from the center device side to the optical terminal device via the optical transmission path to the home in which the CATV reception contract is concluded. An amplifier in the optical terminal device may be controlled so as to supply an electric television signal obtained by converting the optical television signal to the television receiver. In this case, the optical terminal device performs control by converting the optical control signal into an electrical control signal, converts the electrical control signal into the optical control signal again, and transmits it to the center device. Informs that it was done.

  However, in this method, an electrical control signal is converted into an optical control signal and transmitted to the center device side. Therefore, for example, although the amplifier on the optical terminal device side is out of order and the amplifier is controlled to output the electric television signal by the electric control signal, the electric television is actually connected to the television receiver. The center device cannot grasp that no signal is transmitted. In addition, if the television receiver on the home side cannot receive the signal, a complaint will be sent to the center device side, but on the center device side, is there a problem on the television receiver side or a problem on the optical transmission system side? I can't figure out.

  For example, in Patent Document 1, in a device that supplies power to an optical terminal device of an optical transmission system, the level of a television signal output from the optical terminal device is detected, and the detection result is transmitted together with the power monitoring result to optical transmission A monitoring and power supply device that transmits data to a center device via a network different from the system is disclosed.

JP 2008-227842 A

  According to the apparatus of Patent Document 1, since the output level of the television signal is detected and transmitted to the center apparatus side, the above-described problems can be solved. However, a monitoring device must be provided separately from the optical terminal device, which complicates the configuration. In addition, the monitoring result must be transmitted through a network different from the optical transmission system, which further complicates the configuration.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical transmission system and an optical terminal device that can accurately grasp on the center device side whether or not the optical terminal device has failed with a simple configuration.

An optical transmission system according to an aspect of the present invention includes a center device, an optical terminal device that includes an image optical terminal unit and a communication optical terminal unit, and is connected to the center device via an optical transmission path. Transmitting said center apparatus includes an optical television signal obtained by converting the plurality of electrical television signals of different frequency bands, and a light control signal obtained by converting the electric control signal, to the image light terminal unit through the optical transmission path and, and optical communication through said optical transmission path and the communication light terminal unit. The electric television signal different frequency bands, for example, be a television signal in the VHF band and UHF band, it shall consist of an intermediate frequency signal of the satellite. The video optical terminal unit has photoelectric conversion means, and the photoelectric conversion means converts the optical television signal and the light control signal into a plurality of converted electric television signals and converted electric control signals. Transmission means is provided for each of the different frequency bands. That is, a plurality of transmission means are provided. The plurality of transmission means are supplied with the corresponding converted electric television signal, and the plurality of transmission means are external to the video optical terminal unit of the corresponding converted electric television signal according to the converted electric control signal. Each of the output state and the non-output state is controlled. A plurality of level detection means an output level of said plurality of transmission means is detected. An output signal of the level detection means or a comparison result with a predetermined threshold value of the output signal is transmitted to the center device via the optical communication terminal unit.

An optical terminal device according to another aspect of the present invention includes a video optical terminal unit and a communication optical terminal unit, and is connected to the center device via an optical transmission line. The center device outputs an optical television signal obtained by converting a plurality of electric television signals in different frequency bands, and an optical control signal obtained by converting the electric control signal. The video optical terminal unit includes photoelectric conversion means, which converts the optical television signal into a plurality of converted electric television signals and converts the light control signal into a converted electric control signal. The image light terminal unit also has a plurality of transmission means, the plurality of transmission means, provided for each of the different frequency bands, the conversion electrical television signals corresponding is supplied, according to the converted electrical control signal, corresponding Each of the converted electric television signals to be output is controlled to either an output state or a non-output state to the outside of the video optical terminal unit. A plurality of level detection means detect output levels of the plurality of transmission means. An output signal of the plurality of level detection means or a comparison result with a predetermined threshold value of the output signal is transmitted to the center device via the communication optical terminal unit.

  In both aspects, for example, an amplifier, an attenuator, and an open / close switch can be used as the transmission means.

In these configurations, the user of the optical terminal device receives, for example, only the VHF band and the UHF band, receives only the satellite broadcast intermediate frequency signal, or the VHF band, the UHF band, and the satellite broadcast intermediate frequency signal. It is possible to deal with any case of receiving Moreover, in the optical terminal device, the level of the output signal of the transmission means is detected, and the comparison result with the detection result or a predetermined threshold value of the detection result is transmitted to the center device side. It is possible to accurately grasp whether or not an electric television signal is actually output on the terminal device side. In addition, since this detection result or comparison result can be transmitted using the communication optical terminal unit provided in the optical terminal device, it is not necessary to provide a monitoring device separately from the optical terminal device, and this detection result or comparison result There is no need to provide a network for transmission of the results.

  In addition, display means for displaying the output signal of the level detection means or the comparison result may be provided in the optical terminal device. If comprised in this way, the worker who performed the maintenance inspection of the optical terminal device can know the present condition from the display state of a display means.

  As described above, according to the present invention, it is possible to accurately grasp on the center device side whether or not the television signal is normally output from the optical terminal device with a simple configuration.

It is a block diagram of one embodiment of the present invention.

  The optical transmission system of one aspect of the present invention includes a center device 2 and an optical terminal device 4 as shown in FIG. Although only one optical terminal device 4 is shown in the figure, a plurality of optical terminal devices 4 are actually used.

  The center apparatus 2 includes a broadcast system center apparatus 2a and a communication system center apparatus 2b. The optical terminal device 4 also includes a video optical terminal unit, for example, a V-ONU 4a, and a communication optical terminal unit, for example, a D-ONU 4b. The broadcast system center apparatus 2a is connected to the V-ONU 4a via the broadcast system optical transmission path 6a. The communication system center apparatus 2b is connected to the D-ONU 4b and the communication system optical transmission path 6b of the optical transmission path 6. Connected through.

  The broadcast center device 2a converts electric television signals, for example, CATV signals including television broadcast signals in the UHF band and VHF band, and satellite broadcast and / or satellite communication intermediate frequency signals into optical television signals. The optical television signal is transmitted to the V-ONU 4a through the broadcast optical transmission line 6a.

  Also, the broadcast system center device 2a generates control data instructing whether to output a CATV signal, a satellite broadcast and / or satellite communication intermediate frequency signal, or both in the V-ONU 4a. . The broadcast system center apparatus 2a transmits the optical control signal obtained by converting the electrical control signal obtained by modulating the carrier wave with the control data to the V-ONU 4a through the broadcast system optical transmission line 6a. That is, the broadcast system center apparatus 2a and the V-ONU 4a are unidirectional transmission from the broadcast system center apparatus 2a to the V-ONU 4a. The electrical control signal is in a different frequency band from the CATV signal, satellite broadcast, and / or satellite communication intermediate frequency signal.

  The communication system center device 2b is capable of bidirectional communication with the D-ONU 4b. For example, a personal computer (PC) 8 is connected to the D-ONU 4b, and the personal computer 8 uses the communication system center device 2b. For example, an internet connection can be made. Since the configuration of the D-ONU 4b is known, a detailed description thereof will be omitted.

  The V-ONU 4a includes photoelectric conversion means, for example, a photodiode (PD) 10. The photodiode 10 receives the optical television signal transmitted through the broadcast optical transmission path 6a and converts it into a television broadcast signal and an electric control signal. The television broadcast signal and the electric control signal are supplied to an amplifying unit, for example, an amplifying stage 14 via a branching unit, for example, one branching unit 12.

  The amplification stage 14 includes filter means (not shown), and is configured to extract and amplify only the television broadcast signal. The output signal of the amplification stage 14 is supplied to a demultiplexing means, for example, a demultiplexer 16.

  The CATV signal of one demultiplexing output of the demultiplexer 16 is supplied to a transmission means, for example, an amplifying means, specifically, an amplifying stage 18. The amplification stage 18 is configured to amplify the CATV signal. The intermediate frequency signal of satellite broadcasting and / or satellite communication of the other demultiplexing output of the demultiplexer 16 is supplied to transmission means, for example, amplification means, specifically, the amplification stage 20. The amplification stage 20 is configured to amplify an intermediate frequency signal for satellite broadcasting and / or satellite communication.

  An output signal of the amplification stage 18 is supplied to a synthesizing unit, for example, a synthesizer 24, via a branching unit, for example, one branching unit 22. The output signal of the amplification stage 20 is supplied to the synthesizer 24 via a branching unit, for example, one branching unit 26. The synthesizer 24 synthesizes the output signals of both amplification stages 18 and 20 and supplies them to the output terminal 46. The output terminal 46 is connected to a television receiver (not shown).

  The power supply terminals of the amplification stages 18 and 20 are connected to a DC power source via open / close means, for example, open / close switches 28 and 30, and are opened / closed according to a control signal from a control means such as the microcomputer 32. When the microcomputer 32 closes only the open / close switch 28, only the CATV signal that is the output signal of the amplification stage 18 is supplied to the output terminal 46. When the microcomputer 32 closes only the open / close switch 30, only the intermediate frequency signal of satellite broadcasting and / or satellite communication that is the output signal of the amplification stage 20 is supplied to the output terminal 46. When the microcomputer 32 closes both the open / close switches 28 and 30, the CATV signal and the intermediate frequency signal of satellite broadcasting and / or satellite communication are supplied to the output terminal 46. When the microcomputer 32 has both the open / close switches 28 and 30 open, the CATV signal and the intermediate frequency signal for satellite broadcasting and / or satellite communication are not supplied to the output terminal 46.

  The microcomputer 32 controls which one of the opening / closing switches 28 and 30 is closed or both are closed by the branching unit 12 and the electric control signal extracted by the filter 34 is demodulated by a demodulating unit, for example, a demodulating unit 36. This is performed based on the control data demodulated and supplied to the microcomputer 32.

  The CATV signal output from the branch terminal of the one branching device 22 is supplied to level detection means, for example, a detection circuit 38. The detection circuit 38 supplies an output signal representing the level of the CATV signal to the microcomputer 32. Similarly, the intermediate frequency signal of satellite broadcasting and / or satellite communication output from the branch terminal of the one branching device 26 is supplied to level detection means, for example, the detection circuit 40. The detection circuit 40 supplies the microcomputer 32 with an output signal representing the level of the intermediate frequency signal of satellite broadcasting and / or satellite communication.

  The microcomputer 32 digitizes the output signals of the supplied detection circuits 38 and 40 by a built-in A / D conversion circuit, and compares them with predetermined thresholds corresponding to these. When the value of the output signal of the detection circuit 38 is larger than the threshold value predetermined for the detection circuit 38, it can be seen that the CATV signal is normally output from the amplification stage 18 and the CATV system is normal. Similarly, when the value of the output signal of the detection circuit 40 is larger than a predetermined threshold value for the detection circuit 40, the intermediate frequency signal of satellite broadcast and / or satellite communication is normally output from the amplification stage 20, and the satellite broadcast It can be seen that the intermediate frequency signal system of satellite communication is normal. That is, the microcomputer 32 functions as comparison means or determination means.

  These comparison results are supplied to the D-ONU 4b, and then supplied from the D-ONU 4b to the communication system center device 2b via the communication system optical transmission path 6b. A personal computer 42 is connected to the communication system center device 2b, whereby the output state at the amplification stages 18 and 20 of the V-ONU 4a can be grasped.

  Therefore, when the optical control signal is transmitted so as to operate the amplification stages 18 and 20, when the comparison result that the outputs of the amplification stages 18 and 20 are normal is transmitted, the amplification stages 18 and 20 The center device 2 can grasp that the control has been performed as instructed. When the optical control signal is transmitted so that only the amplification stage 18 or only the amplification stage 20 is operated, the comparison result that the output of only the amplification stage 18 is normal or the output of only the amplification stage 20 is normal is transmitted. In this case, the center device 2 can recognize that only the amplification stage 18 or only the amplification stage 20 is controlled as instructed.

  The operation of the amplification stages 18 and 20 is started when the optical terminal device 4 is already installed in the house and there is a new resident in the house. And, according to the resident's request, it is possible to receive only the CATV signal, receive both the CATV signal and satellite broadcast and / or satellite communication intermediate frequency signal, or receive only the satellite broadcast and / or satellite communication intermediate frequency signal. In addition, the amplification stages 18 and 20 are controlled from the center device 2 side. This eliminates the need for an operator to go to the place where the optical terminal device 4 is installed and receive a CATV signal or the like.

  Moreover, the comparison in the microcomputer 32 and the comparison result are always transmitted to the communication system center apparatus 2b via the D-ONU 4b. Therefore, for example, when the user of the optical terminal device 4 complains that the television broadcast cannot be received, the outputs of the amplification stages 18 and 20 are normal in the personal computer 42 on the center device 2 side. If the comparison result is obtained, it is immediately determined that the problem is on the user's television receiver side, and the problem can be solved quickly. Further, when the comparison result that the outputs of the amplification stages 18 and 20 are normal is not obtained in the personal computer 42 on the center apparatus 2 side, the optical television signal is normally transmitted from the broadcast system center apparatus 2a. If it is confirmed that the problem is in the optical terminal device 4 or the broadcast optical transmission line 6a, the problem can be solved quickly.

  In addition, transmission of the comparison result to the center device 2 side is performed using the D-ONU 4b, the communication system optical transmission line 6b, and the communication system center device 2b included in the optical terminal device 4. Therefore, it is not necessary to separately provide a transmission path for transmitting the comparison result, and the equipment cost can be reduced.

  The microcomputer 32 is provided with display means, for example, a plurality of LEDs 44, and is configured so that the comparison result can be confirmed from outside the V-ONU 4a. Therefore, an operator who has performed maintenance and inspection of the optical terminal device 4 can visually recognize the operation state of the amplification stages 18 and 20 by confirming the light emission state of the LED 44.

  In the above embodiment, both the CATV signal and the intermediate frequency signal of satellite broadcasting and / or satellite communication are transmitted to the optical terminal device 4, but depending on the case, for example, only the CATV signal is transmitted to the optical terminal device. 4 may be transmitted. In this case, only the amplification stage 18 is installed in the V-ONU 4a, and an optical control signal is transmitted to the V-ONU 4a when the amplification stage 18 is operated.

  In the above embodiment, whether or not the amplification stages 18 and 20 are operated is controlled. However, the present invention is not limited to this. For example, a variable attenuator is provided in place of the amplification stages 18 and 20, and these attenuation amounts are provided. It is also possible to control the open / close switch, and an open / close switch can be provided in place of the amplification stages 18 and 20 to control the open / close thereof.

  Further, in the above embodiment, the comparison result is transmitted from the microcomputer 32 to the communication center device 2b. However, the digitized output signals of the detection circuits 38 and 40 are transmitted to the communication system center device 2b, and the personal computer. It can also be configured to compare with a threshold at 42 and display the comparison result.

  In the above embodiment, the CATV signal and the satellite broadcast intermediate frequency signal are demultiplexed by the demultiplexer 16, and the CATV signal is supplied to the amplification stage 18 and the satellite broadcast intermediate frequency signal is supplied to the amplification stage 20. A distributor is provided in place of the amplifier 16, the distribution output is supplied to each of the amplification stages 18 and 20, the CATV signal extraction means is provided in the amplification stage 18, and the intermediate frequency of satellite broadcasting and / or satellite communication is provided in the amplification stage 20. A signal extraction means may be provided.

2 Center device 4 Optical terminal device 4a V-ONU (Video optical terminal unit)
4b D-ONU (Communication Optical Terminal Unit)
6a Video transmission line (optical transmission line)
6b Communication system optical transmission line (optical transmission line)
10 Photodiode (photoelectric conversion means)
18 20 Amplification stage (transmission means)
38 40 Detection circuit (level detection means)

Claims (3)

A center device, and an optical terminal device connected via the optical transmission path to the center device, wherein said optical terminal device includes an image light terminal unit and the communication light terminal unit,
Transmitting said center apparatus includes an optical television signal obtained by converting the plurality of electrical television signals of different frequency bands, and a light control signal obtained by converting the electric control signal, to the image light terminal unit through the optical transmission path and, and to optical communication through said optical transmission path and the communication light terminal unit,
The video optical terminal unit is
Photoelectric conversion means for converting the optical television signal and the light control signal into a plurality of converted electric television signals and converted electric control signals;
Provided for each of the different frequency bands, the corresponding converted electric television signal is supplied, and according to the converted electric control signal, the output state of the corresponding converted electric television signal to the outside of the video optical terminal unit is not A plurality of transmission means controlled by any of the output states;
A plurality of level detection means for respectively detecting output levels of the plurality of transmission means;
And an optical transmission system in which an output signal of the plurality of level detection means or a comparison result with a predetermined threshold value of the output signal is transmitted to the center device via the communication optical terminal unit. Different and the optical television signal obtained by converting the plurality of electrical television signal in the frequency band, are connected via the optical transmission path to the center apparatus that outputs an optical control signal obtained by converting the electric control signal, further, the image light terminal portion And a communication terminal unit,
The video optical terminal unit is
Photoelectric conversion means for converting the optical television signal into a plurality of converted electric television signals and converting the light control signal into a converted electric control signal ;
Provided for each of the different frequency bands, the corresponding converted electric television signal is supplied, and according to the converted electric control signal, the output state of the corresponding converted electric television signal to the outside of the video optical terminal unit is not A plurality of transmission means each controlled to one of the output states ;
A plurality of level detection means for detecting each of the output levels of the plurality of transmission means ;
And an optical terminal device that supplies an output signal of the plurality of level detection means or a comparison result with a predetermined threshold value of the output signal to the communication optical terminal unit and transmits the result to the center device.   3. The optical terminal apparatus according to claim 2, further comprising display means for displaying an output signal of the level detection means or the comparison result.

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