KR100642249B1 - Digital multimedia broadcasting using hybrid-fiber coaxial network - Google Patents

Abstract

The present invention is a low-cost digital multimedia broadcasting system using an optical coaxial mixed network, which is an alternative to a repeater with a high investment cost in a shaded area where DBM service is not possible. The 2.6 GHz signal is changed to 800 MHz through a frequency down converter. The present invention relates to a digital multimedia broadcasting system in which a frequency up-converter is installed at an output port of an optical coaxial mixed network of each arc to implement a reduced service using a conventional optical coaxial mixed network.

The present invention for this purpose, using the OCXO (OVEN CONTROLLED CRYSTAL OSCILLATORS) local oscillator 11 to generate a local frequency 600MHz, frequency multiplier 12, multiplying this local frequency 600MHz 3 times to obtain 1.8GHz 3, Frequency mixer 13 to obtain a transmission frequency of 800 MHz by mixing the frequency of 1.8 GHz and 2.6 GHz received from the gap filler, a coupler 14 coupling a 800 MHz of transmission frequency and 600 MHz of a local frequency, and a 600 MHz local frequency. A frequency down converter (10) comprising a signal amplifier (15) for amplifying and a signal amplifier (16) for amplifying the coupled signal and then transmitting the amplified signal to the HFC or CATV network; Duplexer filter 21 for filtering to 800 MHz of transmission frequency and 600 MHz of local frequency, frequency multiplier 22 to obtain 1.8 GHz by multiplying 600 MHz of local frequency by 3, and amplifying the transmitted 800 MHz by signal amplifier 23 to 1.8. A frequency mixer 24 composed of a frequency mixer 24 mixed with GHz to obtain a service frequency of 2.6 GHz, and a signal amplifier 25 amplifying the converted 2.6 GHz signal and finally outputting the signal to the antenna 26. It is characterized by that.

Optical coaxial mixed network, low cost digital multimedia broadcasting system, DMB, HFC, gap filler, DMB repeater

Description

DIGITAL MULTIMEDIA BROADCASTING USING HYBRID-FIBER COAXIAL NETWORK}             

1 is a block diagram of applying a reduced-cost digital multimedia broadcasting system using a optical coaxial mixed network of the present invention to a system using a CATV network;

2 is a block diagram of applying a reduced-cost digital multimedia broadcasting system using an optical coaxial mixed network of the present invention to an in-building application system.

FIG. 3 is a block diagram showing a reduced digital multimedia broadcasting system using an optical coaxial mixed network of the present invention.

Explanation of symbols on the main parts of the drawings

10: Frequency down converter (FDC)

20: Frequency Up Converter (FUP)

30: gap filler

The present invention relates to a low-cost digital multimedia broadcasting system using an optical coaxial mixed network. More specifically, the frequency downconverter (2.6 GHz signal is converted into 800 MHz as an alternative to a repeater having a high investment cost in a shadow area that cannot provide DBM service. FDC: FREQUENCY DOWN CONVERTER (FDC) and then install frequency up-converter (FUC: FREQUENCY UP CONVERTER) at each output port of optical coaxial mixed network to realize saving service using conventional optical coaxial mixed network. It relates to a broadcasting system.

Terrestrial digital multimedia broadcasting (DMB: DIGITAL MULTIMEDIA BROADCASTING), which uses the empty VHF channel 12 for mobile reception, splits one channel, resulting in three blocks. We expect 3-4 channels to come out. It is mainly intended for use in vehicles and aims for free broadcasting. Unlike the terrestrial DMB, there is a satellite DMB that uses satellites to broadcast and has a low reception rate using a kind of repeater called GAP FILLER.

In the implementation of satellite digital multimedia broadcasting (DMB) service network that can enjoy high-definition video and CD-level music anytime, anywhere while on the move, the current network is composed of many expensive gap fillers. There was a disadvantage in itself, that is, the initial investment cost was large.

Meanwhile, HYBRID FIBER COAXIAL (HFC) is a communication technology in which fiber optic cables and coaxial cables are used in different parts of the network to transport broadband content such as video, data, and voice. Local cable TV companies typically use fiber-optic cables to service nodes close to their corporate or home users from cable headends, and coaxial cables can be used to enter individual businesses or homes from these nodes. have.

The advantage of this optical coaxial hybrid network (HFC) is that it can deliver some of the characteristics of fiber optic cables closer to the user without having to replace the existing coaxial cable that is always installed in businesses and homes. Both cable television and telephone companies are applying optical coaxial blended networks to new installations or improving their networks, and in some cases share the same infrastructure for transmitting video and voice conversations within the same system.

In order to solve the shadow area of the digital multimedia broadcasting service of the prior art, the installation of expensive gap fillers or DMB repeaters is required. Therefore, the installation of expensive equipment is indispensable even for the service of the shadow area where the initial investment is large and small.

Conventional digital multimedia broadcasting (DMB) service receives the 2.6GHz phase signal through the antenna, and in the shaded area where satellite signals cannot be received by the terrain and the building, converts the 12GHz satellite signal to 2.6GHz through the gap filler. And, by eliminating the shadow area can perform a digital multimedia broadcasting (DMB) service.

Therefore, multiple ground gap fillers should be installed or DMB repeaters should be installed in shadow areas and in-buildings, and radio frequency and cables will be installed for the construction of digital multimedia broadcasting (DMB) service networks. Installation of high power equipment and relatively large size and installation space of service equipment are required.

The present invention has been invented to implement a low-cost digital multimedia broadcasting (DMB) service network in order to compensate for the above disadvantages, the conventional optical coaxial by implementing a DMB repeater system consisting of a frequency down converter and a plurality of frequency up converters The purpose of this paper is to provide a low-cost digital multimedia broadcasting system using optical coaxial mixed network, which can provide easy and reduced service to inbuilding and shadow areas by using a mixed network or a dedicated CATV network.

The present invention for achieving the above object, the local oscillator 11 generating a local frequency 600MHz using OCXO, the frequency multiplier 12, multiplying this local frequency 600MHz to obtain 1.8GHz by three multiplying three obtained A frequency mixer 13, which obtains a transmission frequency 800 MHz by mixing a frequency of 1.8 GHz and 2.6 GHz received from a gap filler, a coupler 14 coupling 800 MHz of a transmission frequency and 600 MHz of a local frequency, and amplifying a local frequency of 600 MHz. A frequency down converter (10) comprising a signal amplifier (15) and a signal amplifier (16) for amplifying the coupled frequency and then transmitting it to an HFC or CATV network; Duplexer filter 21 for filtering to 800 MHz of transmission frequency and 600 MHz of local frequency, frequency multiplier 22 to obtain 1.8 GHz by multiplying 600 MHz of local frequency by 3, and amplifying the transmitted 800 MHz by signal amplifier 23 to 1.8. A frequency mixer 24 composed of a frequency mixer 24 mixed with GHz to obtain a service frequency of 2.6 GHz, and a signal amplifier 25 amplifying the converted 2.6 GHz signal and finally outputting the signal to the antenna 26. It is characterized by that.

In another embodiment of the present invention, a gap filler through a 12 GHz antenna is installed on top of a CATV operator network or an optical coaxial mixed network (HFC), and a frequency for down-converting a 2.6 GHz signal received through the gap filler to a transmission frequency of 800 MHz. Down-converter is installed, and this frequency signal is amplified and transmitted through the network, up-converted to 2.6 GHz in the lowest call of each network, and then amplified to a certain level to install a frequency up-converter to serve the area. It features.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 is a block diagram showing a reduced-type digital multimedia broadcasting system using the optical coaxial mixed network of the present invention. The present invention is an alternative to a repeater having a high investment cost in a shaded area where digital multimedia broadcasting (DBM) services cannot be provided. After changing the 2.6GHz signal through the frequency down converter 10 to 800MHz, the frequency up-converter 20 is installed in the optical coaxial mixed network output port of each arc to implement a saving service using a conventionally configured coaxial mixed network. It is a digital multimedia broadcasting system.

The frequency down converter 10 includes a local oscillator 11 generating 600 MHz, which is a local frequency, by using OCXO (OVEN CONTROLLED CRYSTAL OSCILLATORS), a frequency multiplier 12, which multiplies this local frequency by 3 3 to obtain 1.8 GHz, A frequency mixer 13, which obtains a transmission frequency of 800 MHz by mixing a 1.8 GHz frequency obtained by multiplying 3 and a 2.6 GHz received from a gap filler (not shown), and a coupler coupling a 800 MHz transmission frequency and 600 MHz local frequency ( 14), a signal amplifier 15 for amplifying the local frequency 600 MHz and a signal amplifier 16 for amplifying the coupled signal and then transmitting the HFC or CATV network.

The frequency up-converter 20 includes a duplexer filter 21 for filtering at 800 MHz of transmission frequency and 600 MHz of local frequency, a frequency multiplier 22 for multiplying 600 MHz of the local frequency 3 to obtain 1.8 GHz, and transmitting the transmitted 800 MHz signal. It consists of a frequency mixer 24 which amplifies in the amplifier 23 and mixes with 1.8 GHz to obtain a service frequency of 2.6 GHz, and a signal amplifier 25 which amplifies the converted 2.6 GHz signal and finally outputs it to the antenna 26. have.

The present invention configured as described above can be implemented by changing the signal of 2.6GHz through the frequency down converter 10 to 800MHz and then installing the frequency up-converter 20 in the optical coaxial mixed network output port of each call. If the transmission frequency is the same as that used in the conventional network service, another frequency below 800 MHz may be used.

1 is a block diagram of applying a reduced-cost digital multimedia broadcasting system using the optical coaxial mixed network of the present invention to a system using a CATV network. On the other hand, the frequency up-converter 20 is connected in the shaded area. It shows the connection between the CATV operator network and the frequency down converter output, and the shaded area shows the service from the final output to the frequency up converter.

FIG. 2 is a block diagram illustrating the application of a low-cost digital multimedia broadcasting system using an optical coaxial mixed network of the present invention to an in-building application system, and includes a 12 GHz antenna (ANT), a standalone gap filler 30, and a 2.6 GHz frequency down converter (10). : FDC) are connected, while frequency up-converters 20: FUC of 1 F-15 F are connected. A conventional HFC or CATV coaxial cable network installed inside a building is shown, and a transmission frequency of 800 MHz is supplied.

Therefore, in the present invention, it is a main advantage to configure the gap filler 30 or the DMB type repeater network, and to use the HFC network which has already established the conventional method of serving the 2.6 MHz signal. In order to use the conventional HFC network, the conversion of the propagation frequency is essential. Therefore, as shown in FIG. 3, the 2.6 GHz signal is converted into the 800 MHz band, down-converted using the frequency down converter 10, and then transmitted to the HFC network to be 2.6 GHz again through the frequency up converter 20 at the final output stage. Can be converted to service.

In the frequency down converter 10, 2.6 GHz is supplied to the frequency mixer 13, 600 MHz of the local oscillator 11 is supplied to the frequency mixer 13 through the frequency multiplier 12, while the signal amplifier ( 15 is supplied to the coupler 14. The 800 MHz output from the frequency mixer 13 is coupled to the 600 MHz, amplified by the signal amplifier 16 and transmitted to the HFC or CATV network.

The frequency up-converter 20 filters the 800 MHz and 600 MHz frequencies transmitted from the HFC or CATV network by the duplexer filter 21, and the 800 MHz is amplified by the signal amplifier 23 and supplied to the frequency mixer 24. 600 MHz is fed to frequency mixer 24 as 1.8 GHz through frequency multiplier 22. The 2.6 GHz output of this frequency mixer 24 will radiate through the signal amplifier 25 to the final antenna 26.

As described above, the reduced-type DMB system of the present invention is composed of a frequency down converter and a frequency up-converter, so that a small output frequency up / down converter is used when implementing the DMB service in a shaded area, so that the initial investment cost, installation, and maintenance are easy. It is configured to.

As shown in FIG. 1 and FIG. 2, the gap filler 30 through the 12 GHz antenna is installed in the shadow area where the CATV network is constructed and the in-building to solve the shadow area of the DMB service. It is installed on the top of the network (HFC), a frequency down converter 10 for down-converting the 2.6GHz signal received through the gap filter 30 to the transmission frequency of 800MHz is installed, and amplifies the coupling signal The frequency up-converter 20 is transmitted to the network and upconverts back to 2.6 GHz in the lowest call of each network, and then amplifies to a predetermined level to serve the area.

Accordingly, the present invention enables the DMB service provider to implement a reduction in the investment cost of the service network construction for the DMB service and the reduction of the expensive service equipment.

As described above, according to the present invention, the network design and service equipment installation cost that is to be initially invested in performing the DMB service are relatively reduced. In the case of the network design, the existing network is already installed in a CATV network or a building. By using the optical coaxial mixed network, the network design cost can be reduced.                     

The present invention has the advantage that it is possible to simply install a low-cost converter wherever service equipment, even where the optical coaxial mixed network is designed by a simple frequency down / up-converter.

In addition, the present invention can be adapted in almost all areas where the optical coaxial mixed network is installed, and the service is possible by simple installation in a wide range of sound regions with one gap filler at the top end.

Claims (6)

Local oscillator generating local frequency 600MHz using OCXO, frequency multiplier that obtains 1.8GHz by multiplying this local frequency 600MHz by 3 times, 1.8GHz obtained by multiplying 3 times by mixing 2.6GHz received from gap filler Consists of a frequency mixer that obtains 800 MHz, a coupler that couples 800 MHz of transmission frequency and 600 MHz of local frequency, a signal amplifier that amplifies local frequency 600 MHz, and a signal amplifier that amplifies the coupled frequency and then transmits it to HFC or CATV network. A frequency down converter 10; Duplexer filter that filters at 800MHz of transmission frequency and 600MHz of local frequency, frequency multiplier that obtains 1.8GHz by multiplying 600MHz of local frequency by 3 times, and amplifies the transmitted 800MHz by signal amplifier and mixes with 1.8GHz to service frequency 2.6GHz Reduced digital multimedia broadcasting system using an optical coaxial mixed network, characterized in that it comprises a frequency mixer and a frequency up-converter (20) consisting of a signal amplifier to amplify the converted 2.6GHz signal and finally output to the antenna. A gap filter through a 12 GHz antenna is installed on top of a CATV operator network or an optical coaxial mixed network (HFC), and a frequency down converter is installed to down-convert the 2.6 GHz signal received through the gap filler to a transmission frequency of 800 MHz. Amplifies the frequency signal and transmits it through CATV operator network or optical coaxial mixed network, upconverts to 2.6GHz from the lowest level call of each network, and then amplifies it to a certain level to install a frequency up-converter to serve the area. Reduction-type digital multimedia broadcasting system using optical coaxial mixed network. The method of claim 2, In the frequency down converter, 2.6 GHz is supplied to the frequency mixer, 600 MHz of the local oscillator is supplied to the coupler through a signal amplifier while 1.8 GHz is supplied to the frequency mixer through a frequency multiplier, and 800 MHz output from the frequency mixer is A low-cost digital multimedia broadcasting system using an optical coaxial mixed network, which is coupled to 600 MHz and amplified by a signal amplifier and transmitted to an HFC or CATV network. The method of claim 2, The frequency up-converter filters the 800 MHz and 600 MHz frequencies transmitted from the HFC or CATV network by the duplexer filter, the 800 MHz is amplified by the signal amplifier and supplied to the frequency mixer, and the 600 MHz is 1.8 GHz through the frequency multiplier to the frequency mixer. And a 2.6 GHz output of the frequency mixer, radiated to the final antenna through a signal amplifier. The method according to claim 3 or 4, A low-cost digital multimedia broadcasting system using an optical coaxial mixed network, wherein the frequency down converter and the frequency up converter have low power. The method of claim 2, The frequency down converter is a low-cost digital multimedia broadcasting system using the optical coaxial mixed network, characterized in that connecting the plurality of frequency up-converter through a CATV operator network or optical coaxial mixed network.

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