KR20000028468A - Satellite broadcast distribution system - Google Patents

Abstract

PURPOSE: A satellite broadcast distribution system is provided to serve a satellite broadcast to a number of households by using only one antenna. CONSTITUTION: A satellite broadcast distribution system distributes a satellite signal of ultrahigh frequency received through one satellite antenna to a number of satellite broadcast receivers. The system comprises: a first low noise converter(110) converting a right polarization of the satellite signal to an intermediate frequency within the established frequency band; a second low noise converter(120) converting a left polarization of the satellite signal to an intermediate frequency; and a frequency synthesizing part(130) outputting an intermediate frequency, which includes the intermediate frequency band of the right polarization and the intermediate frequency of the left polarization by synthesizing the intermediate frequencies converted in each of the first and second low noise converter, to each of a number of satellite broadcast receivers(200).

Description

Satellite broadcasting distribution system

The present invention relates to a system for distributing satellite signals received through antennas to multiple households. More particularly, the present invention relates to satellite broadcast signals received in one home from multiple antennas such as apartments and multi-family homes. The present invention relates to a satellite broadcasting distribution system for multiple households suitable for distribution.

As is well known, satellite broadcasting refers to a broadcasting system in which a broadcasting signal transmitted from a broadcasting station can be directly received by a satellite receiving antenna in each home by using a broadcasting satellite floating in a stationary orbit about 36,000 km over the equator.

Such satellite broadcasting has a high angle of arrival angle of radio waves, so it is not affected by mountains or terrain and uses a directional receiver antenna, which enables uniform broadcasting nationwide without being affected by ghosts by buildings. It's media. Therefore, satellite broadcasting can facilitate services to remote islands and mountain walls, which have been technically difficult in conventional terrestrial broadcasting, and can be used as a countermeasure for astigmatism of television (television) broadcasting. In addition, by utilizing the function to the maximum, it can be an effective means for securing the broadcasting network in case of emergency or disaster, activating the overseas broadcast broadcasting, replacing the relay line, improving the urban reception obstacle, and broadcasting in mobile vehicles such as ships. In addition, due to various advantages such as maximization of channel usage, improvement of video and audio signal quality, additional digital service, ease of data transmission, and improvement of user interface, the use thereof is rapidly increasing.

As described above, in order to receive satellite broadcasts, each home should have a satellite antenna and a satellite broadcast receiver (aka set-top box). For the operation of the satellite antenna and the satellite broadcast receiver, A schematic description will be given with reference to FIGS. 1 and 2 as follows.

1 is a block diagram illustrating a general satellite antenna and a satellite broadcast receiver, and FIG. 2 is a detailed block diagram illustrating the low noise converter of FIG. 1.

First, referring to FIG. 1, a satellite signal in a radio frequency (eg, 11.7 GHz to 12.0 GHz) band received from a satellite (not shown) is received by an intermediate frequency (IF :) by the low noise converter 100. Intermediate Frequency (for example, 950-1450 MHz). That is, as shown in FIG. 2, the satellite mixer of the ultra high frequency signal received from the satellite signal receiver 102 and the local oscillation frequency generated by the local oscillator 104 are mixed in the frequency mixer 106 to generate a satellite broadcast signal having an intermediate frequency. It generates and provides the generated satellite broadcast signal to the satellite broadcast receiver 200 through the cable (C). In this case, the low noise converter 100 is provided with two power sources (for example, 13V and 18V) from a power supply unit (not shown) under the control of the system controller 210. Receives the right polarization of the signal, when the other power is applied, receives the left polarization of the satellite signal, and converts only the received one side polarization into an intermediate frequency to provide to the satellite broadcast receiver 200.

Meanwhile, since the satellite broadcast signal provided from the low noise converter 100 is QPSK modulated, the tuner and the demodulator 220 restore the original signal before modulation, that is, the digital bit stream through demodulation and error correction, and then the system controller. Program service data of a predetermined channel based on the tuning control of 210 is extracted from the bit stream.

The extracted program service data includes video packet data, audio packet data, and the like, and is compressed and encoded based on the MPEG-2 standard. The MPEG decoder 230 decodes the extracted program service data into variable length decoding and inverse. DCT, inverse quantization, motion compensation, and the like are used to decode the original signal (ie, video and audio signal) before compression encoding, and provide the decoded video and audio signal processor 240, respectively.

The video and audio signal processor 240 separately processes a video signal and an audio signal, displays an image through a monitor (not shown), and outputs audio through a speaker (not shown). Provide a user with a broadcast program for a predetermined channel.

On the other hand, in recent years, due to the change in residential culture, multi-family housing such as officetels, apartments, multi-family homes, mansions, villas, and the like are more prevalent than private homes, and therefore, the use of a common antenna is required for cost and aesthetic reasons. That is, in the case of installing a satellite antenna for each individual household in a multi-family apartment house in a multi-storey building, one household per individual household is compared to one satellite antenna in a building in a private house. The installation of the antenna is not only costly, but also very ugly in appearance. Therefore, if the satellite broadcasting can be provided in multiple generations with one satellite antenna, the above-mentioned problems can be solved.

However, in the satellite broadcasting system described above, since the low noise converter 100 provides only channels included in one side polarization (ie, left polarization or right polarization) of the satellite signal at the same time, one antenna for one satellite broadcasting receiver is provided. Need it. That is, when a channel included in one side polarization (eg, left polarization) is selected in one generation, the conventional low noise converter 100 cannot provide a channel included in the other polarization, and thus, in another generation, the other side polarization (eg, For example, when trying to select a channel included in the right polarization, it is not possible to receive satellite broadcasting for the channel.

Therefore, in the case of a multi-family house, in order to receive satellite broadcasting using a single antenna, a satellite broadcasting distribution system capable of receiving satellite broadcasting regardless of left and right polarization is required.

The present invention has been made in view of the above-described point, and an object thereof is to provide a satellite broadcast distribution system capable of receiving satellite broadcast using a single antenna in a plurality of generations.

In order to achieve the above object, in the present invention, in the satellite broadcast distribution system for distributing the ultra-high frequency band satellite signals received through one satellite antenna to a plurality of satellite broadcast receivers, the right polarization of the satellite signal A first low noise converter for converting to an intermediate frequency within a set frequency band; A second low noise converter for converting the left polarization of the satellite signal into an intermediate frequency and shifting the intermediate frequency band for converting the left polarization to an upper or lower side adjacent to the middle frequency band of the right polarization; A frequency synthesizer for synthesizing the intermediate frequencies converted by each of the first and second low noise converters and outputting an intermediate frequency including a middle frequency band of right polarization and an intermediate frequency band of left polarization to each of the plurality of satellite broadcasting receivers. It provides a satellite broadcast distribution system.

1 is a block diagram illustrating a general satellite broadcasting system;

2 is a block diagram illustrating a typical low noise converter;

3 is a block diagram illustrating a satellite broadcast distribution system according to the present invention;

<Description of the code | symbol about the principal part of drawing>

100: low noise converter 102: satellite signal receiver

104: local oscillator 106: frequency mixer

110: first low noise converter 112: first satellite signal receiver

114: first local oscillator 116: first frequency mixer

120: second low noise converter 122: second satellite signal receiver

124: first local oscillator 126: first frequency mixer

130: frequency synthesizer 200: satellite broadcasting receiver

210: system control unit 220: tuner and demodulation unit

230: MPEG decoder 240: video and audio signal processing unit

Hereinafter, with reference to the accompanying Figure 3 will be described in detail a preferred embodiment of the present invention.

3 is a block diagram illustrating a satellite broadcast distribution system according to the present invention.

First, referring to FIG. 3, the satellite broadcasting distribution system according to the present invention is connected in parallel to a cable C extended from the first low noise converter 110, the second low noise converter 120, and the frequency synthesizer 130. Comprised of a plurality of satellite broadcast receiver 200, its individual configuration and function are as follows.

First, the first low noise converter 110 includes a first satellite signal receiver 112, a first local oscillator 114, and a first frequency mixer 116, and is received from an antenna (not shown). Receiving a right polarized wave from a satellite signal in a high frequency band (e.g., 11.7 GHz to 12.0 GHz), and converting the received right polarized wave into a satellite broadcast signal in an intermediate frequency band (e.g., 950 to 1450 MHz); The satellite broadcasting signal of the converted intermediate frequency is provided to the frequency synthesizer 130.

In particular, in order to perform such an operation, each component member provided in the first low noise converter 110 performs the following functions.

First, a fixed voltage (for example, 13 V) is always applied to the first satellite signal receiver 112, thereby receiving the right polarization of the satellite signal received from the antenna, and receiving the right polarization of the received satellite signal. It is provided to one input terminal of the first frequency mixer 116.

On the other hand, the first local oscillator 114 generates a predetermined local oscillation frequency (eg, about 10. 8 GHz) and provides the generated local oscillation frequency to the other input terminal of the first frequency mixer 116.

The first frequency mixer 116 mixes the right side polarization of the satellite signal provided from the first satellite receiver 112 through one input terminal and the local oscillation frequency provided from the first local oscillator 114 through the other input terminal. A satellite broadcast signal (for example, 950 to 1450 MHz) is generated, and the generated satellite broadcast signal of the intermediate frequency band is provided to the frequency synthesizer 130. At this time, the satellite broadcast signal of the intermediate frequency band generated from the first frequency mixer 116 will be a difference signal between the right polarization of the satellite signal and the local oscillation frequency.

Meanwhile, the second low noise converter 120 includes a first satellite signal receiver 122, a first local oscillator 124, and a first frequency mixer 126, and is received from an antenna (not shown). Receives a left polarized wave from a satellite signal of a high frequency band (for example, 11.7 GHz to 12.0 GHz) and uses the received left polarized wave as an intermediate frequency band of the satellite broadcast signal output from the first frequency mixer 116 (for example, And converts the satellite broadcast signal of the intermediate frequency band (for example, 350 to 850 MHz or 1550 to 2050 MHz) adjacent to the 950 to 1450 MHz and then converts the converted satellite broadcast signal to the frequency synthesizer 130. to provide.

In particular, in order to perform such an operation, each component member provided in the second low noise converter 120 performs the following function.

First, a fixed voltage (for example, 18V) is always applied to the second satellite signal receiver 122, thereby receiving a left polarized wave of the satellite signal received from the antenna, and receiving a left polarized wave of the received satellite signal. It is provided to one input terminal of the second frequency mixer 126.

Meanwhile, the second local oscillator 124 generates a preset local oscillation frequency (for example, about 10. 2 GHz or 11.4 GHz) and transmits the generated local oscillation frequency to the other input terminal of the second frequency mixer 126. to provide. At this time, the intermediate frequency band for the left polarization of the satellite signal generated by the second frequency mixer 126 is moved to a frequency band adjacent to the intermediate frequency band for the right polarization of the satellite signal generated by the first frequency mixer 116 ( The frequency magnitude of the local oscillation frequency generated by the second local oscillator 124 to be larger than the frequency magnitude of the local oscillation frequency generated by the first local oscillator 114 (eg, 500 MHz or 600 MHz). Set as large as.

The second frequency mixer 126 mixes the left polarization of the satellite signal provided from the second satellite receiver 122 through one input terminal and the local oscillation frequency provided from the second local oscillator 124 through the other input terminal, thereby mixing the intermediate frequency band. A satellite broadcast signal (for example, 350 to 850 MHz or 1550 to 2050 MHz) is generated, and the generated satellite broadcast signal of the intermediate frequency band is provided to the frequency synthesizer 130. At this time, the satellite broadcast signal of the intermediate frequency band generated from the second frequency mixer 126 is also similar to the satellite broadcast signal of the intermediate frequency band generated from the first frequency mixer 116, and the left polarization of the satellite signal and the second local oscillator are performed. It will be the difference signal of the local oscillation frequency generated at 124.

On the other hand, the frequency synthesizer 130 is an intermediate frequency band provided by the first frequency mixer 116 (eg, 950 to 1450 MHz) and an intermediate frequency band provided by the second frequency mixer 126 (eg, And synthesize a 350 to 850 MHz or 1550 to 2050 MHz signal to generate a satellite broadcast signal having an extended frequency band (for example, 350 to 1450 MHz or 950 to 2050 MHz), and convert the generated satellite broadcast signal into a cable (C). Through each of the plurality of satellite broadcast receiver 200 is provided.

Satellite broadcast signals applied to each of the satellite broadcast receivers 200 are sequentially processed by the tuner and demodulator 200, the MPEG decoder 300, and the audio and video signal processor 400 to display images of broadcast programs of a predetermined channel. As it is output as a voice, since it has been described in the above-described prior art, it will be omitted to avoid duplication.

When the present invention described above is used in a multi-family dwelling house or in a private house using multiple satellite broadcasts, satellite broadcast signals may be provided from a plurality of satellite broadcast receivers through one antenna, thereby reducing costs. And aesthetic effect can be obtained.

Claims (2)

In the satellite broadcast distribution system for distributing the ultra-high frequency band satellite signals received through one satellite antenna to a plurality of satellite broadcast receivers, A first low noise converter converting the right polarization of the satellite signal into an intermediate frequency within a preset frequency band; A second low noise converter for converting the left polarization of the satellite signal into an intermediate frequency and shifting the intermediate frequency band for converting the left polarization to an upper or lower side adjacent to the middle frequency band of the right polarization; A frequency synthesizer for synthesizing the intermediate frequencies converted by each of the first and second low noise converters and outputting an intermediate frequency including a middle frequency band of right polarization and an intermediate frequency band of left polarization to each of the plurality of satellite broadcasting receivers. Satellite broadcast distribution system. The method of claim 1, wherein the first low noise converter, A first satellite signal receiver for receiving a right polarization of the satellite signal; A first local oscillator for generating a local oscillation frequency; And a frequency mixer for generating an intermediate frequency by mixing the right polarization of the satellite signal and the local oscillation frequency. The second low noise converter, A second satellite signal receiver for receiving a left polarization of the satellite signal; A second local oscillator for generating a local oscillation frequency that is larger or smaller than a local oscillation frequency generated by the first local oscillator by a predetermined frequency band; And a frequency mixer for generating an intermediate frequency by mixing the left polarization of the satellite signal and the local oscillation frequency.