KR100502496B1 - Repeating apparatus for satellite broadcasting - Google Patents

Abstract

Disclosed is a satellite broadcast terrestrial repeater capable of retransmitting downlink satellite signals from a multi-satellite composed of a plurality of satellites with a minimum number of repeaters. The satellite broadcasting terrestrial repeater according to the present invention outputs a frequency rearranged polarized signal by separately amplifying satellite signals received from multiple satellites according to satellites and polarizations, rearranging frequencies, and synthesizing the frequency rearranged signals for each polarized wave. And a transmission antenna unit for receiving a signal output from the low noise amplifier unit and simultaneously retransmitting the frequency rearranged polarized signal to a subscriber side.

The satellite broadcasting terrestrial repeater according to the present invention can retransmit downlink satellite signals from multiple satellites to subscribers using one satellite broadcast repeater through frequency rearrangement, which is easy to install, less aesthetics, and more complicated. Is low. It is also possible to retransmit a plurality of types of polarized signals using one transmission antenna.

Description

Satellite broadcasting terrestrial broadcasting device

The present invention relates to a satellite broadcast terrestrial relay apparatus, and more particularly, to a satellite broadcast terrestrial relay apparatus capable of relaying downlinked satellite signals from a plurality of satellites using one satellite broadcast terrestrial relay apparatus. .

Satellites are classified into a communication satellite (CS) and a broadcast satellite (BS). Communication satellites can be categorized into regional communication satellites, domestic communication satellites, and international communication satellites according to the usage range by region, and fixed communication satellites that relay communications with fixed ground stations, and mobile and fixed stations such as vehicles, ships, and aircrafts. Alternatively, there are mobile communication satellites which communicate with each other. A broadcast satellite (BS) is a satellite broadcast that can receive TV broadcast signals from ground stations, pass through amplifiers, and then directly receive them through parabolic antennas installed in each home on the ground.

Low Noise Blockdown Converter (LBN) functions as follows in satellite broadcasting and communication systems. The first is the amplification function. In other words, the satellite signal from the long distance of the geostationary orbit about 36,000km from the ground should be amplified because the output is reduced. The second removes noise from the received satellite signal. Third, because the high frequency band of 12Ghz band is used for transmission from satellite, frequency conversion converts to the frequency of 950Mhz ~ 2,150Mhz band that can be used in satellite receiver (Receiver: Set Top Box).

For example, a low noise block down converter (LBN) converts and amplifies signals of the SHF band (3.5 GHz to 12 GHz) received from the receiving antenna into IF signals of the 1 GHz band and transmits them to the receiver. The LNB preferably has a small noise figure. Functions fall into two broad categories. First, the radio waves that have passed through the stratosphere and the atmosphere at a distance from the orbit, for example, about 36,000 km from the ground, must be amplified because their output is reduced. That is, the LNB performs an amplification action. Next, the LNB removes noise and noise from the received satellite signal waves. Next, since the LNB uses a high frequency band of 3.5 GHz to 12 GHz when receiving the first satellite radio wave, the LNB converts the frequency into the 950 MHz to 2150 MHz band that can be used in a set top box (satellite receiver).

These LNBs can be broadly divided into C-BAND LNBs and KU-BAND LNBs. The C-BAND LNB converts and amplifies satellite frequencies in the C-BAND band into intermediate frequencies that can be recognized by the receiver. The KU-BAND LNB converts and amplifies satellite frequencies in the KU-BAND band to intermediate frequencies that the receiver can recognize. This device, which is located in front of the antenna before sending the C-BAND (3-4 GHz) or KU-BAND (10-12 GHz) radio waves transmitted from the satellite to the satellite receiver (set-top box), is also called a low noise converter and is often called an LNB. . The intermediate frequency (IF) signal corresponds to the frequency of the signal output from the LNB (Converter) which converts the signal received from the satellite antenna (parabolic antenna) to another frequency band (1 GHz) and sends it to the tuner (receiver). .

On the other hand, there is a problem that the satellite signal to be received by the satellite receiver antenna of the subscriber from the satellite is blocked due to the high-rise buildings in the apartment dense area or downtown building area. In this way, the area where the downlink broadcast signal is not received is called a shaded area. In shaded areas, a repeater is used to receive and amplify satellite signals and to retransmit the amplified satellite signals to satellite subscribers.

In recent years, many countries serving satellite broadcasting have multiple satellites using the same frequency band. When attempting to retransmit satellite signals from multiple satellites to a receiver using a relay device, the technical limitation for the relay device design is that the satellites to be served use the same frequency band rather than the increase in the number of satellites. Depends on whether or not. For example, the first case where a single satellite is used and transponders used inside the satellite use only polarization differently in the same frequency band, and two satellites each have a frequency band assigned thereto. There is a second case. Transponder refers to a device mounted on a communication satellite in data communication through the communication satellite. The transponder receives the signal from the transmitting station on the ground, amplifies the signal to an appropriate magnitude, and passes it back to the receiving station on the ground.

Polarization can be divided into horizontal polarization and vertical polarization according to the plane to which the amplitude axis of the wave belongs, that is, the angle between the polarization plane and the ground is horizontal or vertical. Horizontal polarization is a radio wave emitted from the earth and the antenna which is a horizontal device, and is called abbreviation H polarization using Horizontal, which means horizontal. Vertical polarization is an electric wave emitted from the earth and the vertical device antenna and is called abbreviation V polarization using VERTICAL which means vertical. In addition, there are left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP) according to the form of propagation while the polarized surface rotates in a spiral shape according to time and propagation distance.

The repeater is a problem of technical limitations for retransmission in the first case where a plurality of transponders included in one satellite or multiple satellites retransmit downlink satellite signals using only polarization in the same frequency band.

In addition, up to now, the number of relay devices has to be increased in order to retransmit satellite signals received from multiple satellites using a conventional satellite broadcast terrestrial broadcast device. However, in order to install a plurality of relay devices in a limited space, there are problems that many constraints such as installation cost, aesthetics, and complexity follow.

An object of the present invention is to provide a satellite broadcasting terrestrial relay apparatus capable of retransmitting downlink satellite signals from a multi-satellite composed of a plurality of satellites with a minimum number of relay apparatuses.

In accordance with an aspect of the present invention, a satellite broadcast terrestrial relay apparatus separately amplifies satellite signals received from multiple satellites according to satellites and polarizations, rearranges frequencies, and synthesizes frequency rearranged signals by polarization. A low noise amplifier for outputting a frequency rearranged polarized signal; And a transmission antenna unit for receiving the signal output from the low noise amplifier and retransmitting the frequency rearranged polarized signal to the subscriber side at the same time.

The low noise amplification unit may include: a plurality of low noise amplifier stages for separately amplifying satellite signals received from multiple satellites according to satellites and polarizations; A frequency rearrangement unit for rearranging frequency bands of the received satellite signals by mixing satellite signals amplified and amplified between the low noise amplifier stages with signals having a predetermined frequency; A band pass filter for passing only a band of the frequency rearranged signal; And a synthesizer for synthesizing each signal band for each polarized wave.

The frequency rearrangement unit may include a voltage controlled oscillator for outputting an oscillation signal having a predetermined frequency; A frequency multiplier that multiplies the oscillation signal output from the voltage controlled oscillator; And a mixing unit which shifts the frequency band of the satellite signal by mixing the multiplied signal and the satellite signal.

In addition, the multi-satellite has an L band of 1,525 to 1,559 MHz, an S band of 2,170 to 2,200 MHz, a C band of 3,500 to 4,200 MHz, an X band of 7,250 to 7,750 MHz, and a 10.95 to 12.75 GHz band on a downward basis. Satellites using a Ku band, a Ku (DBS) band of 11.70 to 12.00 Hz, a Ka band of 18.10 to 21.20 Hz, and an E band of 19.70 to 21.20 Hz.

The transmitting antenna unit may further include: a first transmitting antenna which receives a signal received through an SMA connector having a first polarized signal port into a circular waveguide through a probe parallel to the ground, and transmits a first polarized wave; And a second transmission antenna for introducing a signal received through the SMA connector having a second polarization signal port into a circular waveguide through a probe perpendicular to the ground, and transmitting a radio wave of the second polarization.

Alternatively, the first transmission antenna and the second transmission antenna may further include a dielectric provided at a predetermined angle with the ground in the circular waveguide to form a circular polarization.

The low noise amplifier may further include an isolator for stabilizing the system or protecting the power amplifier by suppressing the high frequency signal input or output from being carried.

In addition, according to another aspect of the present invention, a satellite broadcast terrestrial relay device separately amplifies satellite signals received from multiple satellites according to satellites and polarizations, rearranges frequencies, and polarizes frequency rearranged signals. A low noise amplifier for synthesizing each other and outputting a frequency rearranged polarized signal; And a transmission antenna which receives the signal output from the low noise amplifier and simultaneously retransmits the frequency rearranged polarization signal to the subscriber side using one antenna.

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

Figure 1 shows the structure of a satellite broadcasting relay system to which the satellite broadcasting terrestrial relay apparatus according to the first embodiment of the present invention is applied. Referring to FIG. 1, a satellite broadcasting relay system using a satellite broadcasting terrestrial relay apparatus according to a first embodiment of the present invention includes a multi-satellite unit 10 including a plurality of satellites 10-1 and 10-2, and a satellite. The broadcast terrestrial relay device 12, the subscriber receiver 14, and the TV 16 are provided. The satellite broadcast terrestrial repeater 12 includes a reflector 122, a low noise amplifier 124, and a transmission antenna unit 126. The subscriber receiver 14 includes a low noise blockdown converter (LNB) and a set top box 144.

The satellite broadcasting terrestrial repeater according to the present invention includes an L band having a frequency band of 1,525-1,559 MHz, an S band of 2,170-2,200 MHz, a C band of 3,500-4,200 MHz, an X band of 7,250-7,750 MHz, and a band 10.95. To cope with a multi-satellite consisting of any combination of satellites using a Ku band of -12.75 GHz, a Ku (DBS) band of 11.70 to 12.00 GHz, a Ka band of 18.10 to 21.20 GHz, and an E band of 19.70 to 21.20 GHz It is possible to design within the scope of the invention as defined by the appended claims. However, in the present specification, for convenience of description, the frequency bands of the downlink signals F1 and F2 of the first satellite 10-1 and the second satellite 10-2 use the same frequency band as 12.25 kHz to 12.75 kHz. As an example, downlink transmission by V and H polarization from each satellite will be described.

According to the present invention, when retransmitting a signal received from the satellites 10-1 and 10-2, the frequency band of the received satellite signal is shifted by shifting the frequency band of the received satellite signal by polarization to expand the frequency band at the time of retransmission. ) To change the structure of the low noise amplifier. In addition, according to the present invention, it is possible to retransmit satellite signals using one relay device for any multi-satellites having the same frequency band or different frequency bands. As an example, a case where a first satellite and a second satellite using a V polarized signal and an H polarized signal in a 12.75 kHz band as a downlink frequency is used as a multi-satellite will be described.

FIG. 2 is a block diagram illustrating an example of a structure of a low noise amplifier included in the satellite broadcast terrestrial repeater shown in FIG. 1. Referring to FIG. 2, satellite signals introduced into the relay device according to the present invention include a V polarization signal and an H polarization signal received from a first satellite, and a V polarization signal and an H polarization signal received from a second satellite. The H polarization signal and the V polarization signal received from the first satellite SAT1 are separately input to the first low noise amplifier 210 and the second low noise amplifier 220, respectively. In addition, the H polarized signal and the V polarized signal received from the second satellite SAT2 are input to the third low noise amplifier 230 and the second low noise amplifier 240, respectively. The power supply unit (not shown) receives a predetermined AC voltage and supplies, for example, a bias voltage having a DC voltage of 15V to the low noise amplifier 124 through a coaxial cable.

The first low noise amplifying unit to the fourth low noise amplifying unit 210, 220, 230, and 240 each include an amplifying unit including an isolator and six amplifying stages at the input stage and the output stage, respectively, preferably after the three stage amplification stage. Place it.

The H polarized signal from the first satellite input to the first low noise amplifier 210 is input to the amplifier 214 through the isolator 212a. The isolators 212a and 212b of the first low noise amplifier 210 and the isolators of the second low noise amplifier 220 to the fourth low noise amplifier 240 are input or output from a microwave repeater or satellite communication system. By suppressing the transmission of high frequency signals, the system stabilizes or protects the power amplifier. Such isolators can be selectively used in various types depending on the characteristic value, structure, frequency band used.

Next, in the first low noise amplifier 210, the mixer 217 mixes the H polarized signal received from the first satellite and a signal of -500 MHz, which is generated in the oscillator 216 and is in phase with the input signal. . The frequency band of the H polarized signal received from the first satellite is in the 12.25 to 12.75 kHz band, which is mixed with a signal of -500 MHz, where-represents an antiphase with the input signal, thereby allowing the first band to be in the 12.25 to 12.75 kHz band. The H polarized signal from the satellite is shifted to a signal in the 11.75 to 12.25 Hz band.

In addition, the mixing unit 227 in the second low noise amplifier 220 inputs a signal of -500 MHz, generated by the oscillator 226 and out of phase with the input signal, to be mixed with the V polarized signal received from the first satellite. . The frequency band of the V polarized signal received from the first satellite is 12.25-12.75 kHz, which is mixed with a signal of -500 MHz, where-indicates that it is out of phase with the input signal, thereby allowing the first satellite to be in the 12.25-12.75 GHz band. The V polarized signal from is shifted to a signal in the 11.75 to 12.25 Hz band.

Next, in the third low noise amplifier 230, the pad PAD 236 delays and outputs an input signal by the processing delay time of the mixing units 217 and 227. The frequency band of the H polarized signal received from the second satellite is 12.25 to 12.75 kHz, and the frequency band of the signal output from the pad 236 maintains the same 12.25 to 12.75 kHz as the frequency band of the H polarized signal. Similarly, in the fourth low noise amplifier 240, the pad PAD 246 delays and outputs an input signal by the processing delay time of the mixing units 217 and 227. The frequency band of the V polarized signal received from the second satellite is 12.25 to 12.75 Hz, and the frequency band of the signal output from the pad maintains the same 12.25 to 12.75 Hz as that of the V polarized signal.

Next, the band pass filters 218, 228, 238, and 248 respectively include a first low noise amplifier 210, a second low noise amplifier 220, a third low noise amplifier 230, and a fourth low noise amplification amplifier. The bands are sufficiently spaced by bandpass filtering the signals amplified by the unit 240.

Now, the first combiner 260 outputs the synthesized H polarized signal by synthesizing the H polarized signals through the first low noise amplifier 210 and the third low noise amplifier 230. That is, the frequency band of the synthesized H polarized signal is 11.75 ~ 12.75 kHz band. In addition, the second combiner 262 outputs the synthesized V polarized signal by synthesizing the V polarized signals through the second low noise amplifier 220 and the fourth low noise amplifier 240. That is, the frequency band of the synthesized V polarized signal is 11.75 ~ 12.75 kHz band. A synthesized H polarized signal and a V polarized signal are output through an SMA (Sub Miniature A) connector (not shown) having two output ports, respectively. SMA connectors refer to high performance connectors suitable for applications above 10 GHz.

3A and 3B are cross-sectional views illustrating the structure of the circular waveguide in the transmitting antenna 126 that can be applied to the satellite broadcasting terrestrial repeater of FIG. Referring to FIG. 3A, the synthesized H polarization signal received through the SMA connector 302 is introduced into a circular waveguide through a probe 304 that is parallel to the ground, and the incoming signal is made of a dielectric material 45 degrees with the ground. 306) forms a propagation of circular polarizations, for example RHCP polarizations. Also, referring to FIG. 3B, a signal received through the SMA connector 322 is introduced into a circular waveguide through a probe 324 perpendicular to the ground, and the incoming signal is 45 degrees from the dielectric 326. Thereby to form a propagation of circular polarization, for example, LHCP polarization. If there is no dielectric in the transmission antennas shown in FIGS. 3A and 3B, the H antenna signal and the V polarization signal may be used as antennas for transmission by dividing the polarized signals.

On the other hand, Figure 4 is a view illustrating a process for rearranging the frequency by the satellite broadcast terrestrial relay apparatus according to an embodiment of the present invention. Referring to FIG. 4, the frequency combination of the satellite signal downlinked from the multi-satellite to the relay device according to the embodiment of the present invention, the frequency band of the first satellite and the second satellite is 12.25 ~ 12.75 kHz and uses the same band Each satellite uses V polarization and H polarization. The frequency band of the signal retransmitted to the subscriber receiver in the relay device according to the embodiment of the present invention is extended to 11.75 ~ 12.75 kHz as shown in FIG.

Referring back to FIG. 1, the signals F3 and F4 to be retransmitted are retransmitted as V polarized and H polarized signals while maintaining a polarization scheme of downlinked signals from satellites when a dielectric is not inserted into the transmission antenna. When the dielectric is inserted, the LHCP polarization signal and the RHCP polarization signal are retransmitted. Since the retransmission signals sent from the respective transmission antennas have different polarization schemes, there is no interference between the retransmission signals.

In the relay device as described above, the signals input to the low noise amplifiers 210, 220, 230, and 240 are separately input from the satellites 10-1 and 10-2, but from the low noise amplifier 124. The output signal is synthesized for each polarization of the V polarization signal and the H polarization signal. In FIG. 1, each of two transmission antennas constituting the transmission antenna unit 126 separately transmits a V polarization signal and an H polarization signal input through the SMA connector (not shown) to the subscriber. Thus, the relay device 12 according to the embodiment of the present invention retransmits the downlink satellite signal from the multi-satellite unit 10 to the subscriber side using one relay device.

Now, the Low Noise Blockdown Converter (LNB) of the subscriber receiver 14 receives the satellite signal retransmitted through the relay device 12 to amplify and remove the noise, and as shown in Table 1 below. The oscillation frequency is used to convert an intermediate frequency signal of a band usable by the set-top box 144. The set-top box 144 extracts the broadcast signal using the intermediate frequency signal, and the user can watch the satellite broadcast through the TV 16.

Satellite Polarization method Shift frequency Rearrangement frequency First satellite V polarization -500 MHz 11.25 to 12.25 Hz (synthesized V polarization) H polarization -500 MHz 11.25 to 12.25 Hz (synthesized H polarization) Second satellite V polarization 0 MHz 11.75 to 12.75 ㎓ (synthesized V polarization) H polarization 0 MHz 11.75 to 12.75 ㎓ (synthesized H polarization)

In the satellite broadcasting terrestrial repeater according to the present invention as described above, signals input to the low noise amplifiers 210, 220, 230, and 240 are separately input from the respective satellites 10-1 and 10-2, The signal output from the low noise amplifier 124 is synthesized for each polarization of the V polarization signal and the H polarization signal and output. In FIG. 1, each of the two transmit antennas constituting the transmit antenna unit 126 separates the V polarization signal and the H polarization signal input through the SMA connector (not shown) and the RF cable connected to the SMA connector to the subscriber. To the enemy. Thus, the relay device 12 according to the embodiment of the present invention retransmits the downlink satellite signal from the multi-satellite unit 10 to the subscriber side using one relay device.

In the first embodiment, retransmission for each polarized V polarization and H polarization has been described as an example. However, as will be understood by those skilled in the art, left-hand circular polarization (LHCP) and RHCP depending on the structure of a transmission antenna (Right-Hand Circular Polarization) can also be retransmitted by polarization. The relay device as in the first embodiment of the present invention can use the existing retransmission antenna as it is.

Next, the satellite broadcasting terrestrial relay apparatus according to the second embodiment of the present invention retransmits a plurality of types of polarized signals using one transmission antenna by changing the structure of an existing transmission antenna. 5 shows a structure of a satellite broadcasting relay system using a satellite broadcast terrestrial relay apparatus according to a second embodiment of the present invention. Referring to FIG. 5, a satellite broadcasting relay system using a satellite broadcasting terrestrial relay apparatus according to a second embodiment of the present invention includes a multi-satellite unit 50 including a plurality of satellites 50-1 and 50-2, and a satellite. The broadcast terrestrial relay device 52, the subscriber receiver 54, and the TV 56. The satellite broadcast terrestrial repeater 52 includes a reflector 522, a low noise amplifier 524, and a transmission antenna 526. The subscriber receiver 54 includes a low noise blockdown converter (LNB) and a set top box 544.

The operations of the satellite broadcast terrestrial repeater 52 and the subscriber receiver 54 according to the second embodiment of the present invention are similar to those of the satellite broadcast terrestrial repeater 12 according to the first embodiment of the present invention described with reference to FIG. 1. Since the operation is the same as that of the subscriber receiver 14, the description is omitted within the scope not impairing the core of the present invention. However, the transmission antenna 526 of the satellite broadcasting terrestrial repeater according to the second embodiment of the present invention has two inputs for receiving an amplified signal from the low noise amplifier 524 for outputting polarized signals through a plurality of output ports. It has a port.

FIG. 6 is a cross-sectional view illustrating the structure of a circular waveguide in a transmission antenna that can be applied to the satellite broadcasting terrestrial repeater of FIG. 5. Referring to FIG. 6, the V polarization signal and the H polarization signal received through the SMA connectors 602 and 622 are introduced into the circular waveguide through the probes 604 and 624 which are horizontal and vertical with the ground, respectively. Is formed by a circular polarization, for example, RHCP polarization and LHCP polarization, respectively, by a dielectric 626 at 45 degrees to the ground. If there is no dielectric in the transmission antennas shown in FIG. The signal and the H polarized signal can be classified by polarization and transmitted simultaneously as one transmission antenna. The satellite broadcasting terrestrial repeater using the improved transmission antenna as described above is simpler to install and requires less installation space.

Next, FIG. 7 illustrates a structure of a satellite broadcasting relay system using the satellite broadcast terrestrial relay apparatus according to the third embodiment of the present invention. Referring to FIG. 7, a satellite broadcasting relay system using a satellite broadcasting terrestrial relay apparatus according to a third embodiment of the present invention includes a multi-satellite unit 70 including a plurality of satellites 70-1 and 70-2, and a satellite. It consists of a broadcast terrestrial relay device 72, a subscriber receiver 74, and a TV 76. The satellite broadcast terrestrial repeater 72 includes a reflector 722, a low noise amplifier 724, and a transmit antenna 726. The subscriber receiver 74 includes a low noise blockdown converter (LNB) and a set top box 744.

FIG. 8 is a block diagram illustrating an example of a structure of a low noise amplifier included in the satellite broadcast terrestrial repeater shown in FIG. 7. Referring to FIG. 8, the satellite signals introduced into the relay device according to the present invention include an H polarized signal and a V polarized signal received from a first satellite and an H polarized signal and a V polarized signal received from a second satellite. The H polarization signal and the V polarization signal received from the first satellite SAT1 are separately input to the first low noise amplifier 810 and the second low noise amplifier 820, respectively. In addition, the H-polarized signal and the V-polarized signal received from the second satellite SAT2 are input to the third low noise amplifier 830 and the second low noise amplifier 840, respectively.

The first low noise amplifying unit to the fourth low noise amplifying unit 810, 820, 830, and 840 include an amplifying unit including six amplifying stages, each including an isolator at an input stage and an output stage, and preferably after the three stage amplification stage. Place it.

The H polarized signal from the first satellite input to the first low noise amplifier 810 is input to the amplifier 814 through the isolator 812a. The isolators 812a and 812b of the first low noise amplifier 810 and the isolators of the second low noise amplifier 820 to the fourth low noise amplifier 840 are input or output from a microwave repeater or a satellite communication system. By suppressing the transmission of high frequency signals, the system stabilizes or protects the power amplifier. Such isolators can be selectively used in various types depending on the characteristic value, structure, frequency band used.

In the first low noise amplifier 810, the mixing unit 817 mixes the H polarized signal received from the first satellite and a signal of -500 MHz generated by the oscillator 816 and out of phase with the input signal. The frequency band of the H polarized signal received from the first satellite is in the 12.25 to 12.75 kHz band, which is mixed with a signal of -500 MHz, where-represents an antiphase with the input signal, thereby allowing the first band to be in the 12.25 to 12.75 kHz band. The H polarized signal from the satellite is shifted to a signal in the 11.75 to 12.25 Hz band.

In addition, in the second low noise amplifier 820, the pad PAD 826 delays and outputs an input signal by the processing delay time of the mixing unit 817. The frequency band of the V polarized signal received from the first satellite is 12.25 to 12.75 kHz, and the frequency band of the signal output from the pad 826 maintains the same 12.25 to 12.75 kHz as the frequency band of the V polarized signal.

In addition, in the third low noise amplifier 830, the mixing unit 837 inputs a signal of -1500 MHz generated by the oscillator 836 and is out of phase with the input signal, and mixes the H polarized signal received from the second satellite. . The frequency band of the H polarized signal received from the second satellite is 12.25-12.75 kHz, which is mixed with a signal of -1500 MHz, where-indicates that it is out of phase with the input signal, thereby causing the second satellite to be in the 12.25-12.75 GHz band. The H polarized signal from is shifted into a signal in the 10.75 to 11.25 Hz band.

In the fourth low noise amplifier 840, the mixing unit 847 inputs a signal of -1000 MHz, generated by the oscillator 846 and out of phase with the input signal, to be mixed with the V polarized signal received from the second satellite. . The frequency band of the V polarized signal received from the second satellite is 12.25-12.75 kHz, which is mixed with a signal of -1000 MHz, where-represents an antiphase with the input signal, thereby allowing the second satellite to be in the 12.25-12.75 GHz band. The H polarized signal from is shifted to a signal in the 11.25 to 11.75 kHz band.

Next, the band pass filters 818, 828, 838, and 848 respectively include a first low noise amplifier 810, a second low noise amplifier 820, a third low noise amplifier 830, and a fourth low noise amplifier. The bands are sufficiently separated by band pass filtering the signals amplified by the unit 840.

Now, the first combiner 860 synthesizes the H polarized signal and the V polarized signal through the first low noise amplifier 810 and the second low noise amplifier 820, and the second synthesizer 862 The H-polarized signal and the V-polarized signal through the third low noise amplifier 830 and the fourth low noise amplifier 840 are synthesized. The third combining unit 870 inputs and outputs an output signal of the first combining unit 860 and an output signal of the second combining unit 862. The frequency band of the signal synthesized by the third combining unit 870 is 10.75 to 12.75 kHz, which is relatively wide band. The synthesized signal is output through a SMA (Sub Miniature A) connector having one output port.

FIG. 9 is a block diagram illustrating another example of the structure of the low noise amplifier included in the satellite broadcasting terrestrial repeater shown in FIG. 7. Referring to FIG. 9, the signal generator 902 generates a signal having a frequency of 100 MHz using, for example, a phase locked loop (PLL) circuit and a voltage controlled oscillator (VCO). The first multiplier 904, the second multiplier 906, and the third multiplier 908 multiply the signals of the frequency 100 MHz generated by the signal generator 902 by 5, 10, and 15 times, respectively. To generate 500 MHz, 1000 MHz, and 1500 MHz signals. The generated signal rearranges the frequencies of the satellite signals when multiplied by satellite signals received from each satellite.

FIG. 10 is a diagram illustrating a process of rearranging frequencies by the satellite broadcasting terrestrial repeater according to the third embodiment of the present invention. Referring to FIG. 10, the frequency combination of the satellite signal downlinked from the multi-satellite to the relay device according to the embodiment of the present invention, the frequency band of the first satellite and the second satellite is 12.25 ~ 12.75 kHz and uses the same band Each satellite uses V polarization and H polarization. The frequency band of the signal retransmitted to the subscriber receiver in the relay device according to the embodiment of the present invention is extended to 10.75 ~ 12.75 kHz.

Satellite Polarization method Shift frequency Rearrangement frequency Local Oscillation Frequency of the Receiver First satellite V polarization -1000 MHz 11.25 ~ 11.75 ㎓ 10.2 ㎓ H polarization -1500 MHz 10.75 ~ 11.25 ㎓ 9.7 ㎓ Second satellite V polarization 0 12.25-12.75 ㎓ 11.2 ㎓ H polarization -500 MHz 11.75-12.25 ㎓ 10.7 ㎓

Now, the Low Noise Blockdown Converter (LNB) of the subscriber receiver 74 receives the satellite signal retransmitted through the relay device 72 to amplify and remove the noise, and as shown in Table 2 above. The same local oscillation frequency is used to convert an intermediate frequency signal in a band usable by the set top box 744. The set-top box 744 extracts a broadcast signal using an intermediate frequency signal, and a user can watch satellite broadcasts serviced by multiple satellites through the TV 76.

In the above embodiments, a case in which arbitrary satellites using a V polarization signal and an H polarization signal in a band of 12.25 to 12.75 kHz is used as a multi-satellite is described as an example, but the satellite broadcasting relay apparatus according to the present invention has various frequency bands, For example, the L band of 1,525-1,559 MHz, the S band of 2,170-2,200 MHz, the C band of 3,500-4,200 MHz, the X band of 7,250-7,750 MHz, the Ku band of 10.95-12.75 GHz for the downlink reference. In accordance with the appended claims to accommodate any combination of satellites using a Ku (DBS) band of 11.70 to 12.00 Hz, a Ka band of 18.10 to 21.20 Hz, and an E band of 19.70 to 21.20 Hz It is possible to design within the scope of the invention as defined. That is, the above embodiments are illustrative for the purpose of understanding the present invention and various modifications and variations are possible by those skilled in the art within the scope of the present invention as defined by the appended claims. Accordingly, the scope of rights of the satellite broadcasting terrestrial relay apparatus according to the present invention as defined by the appended claims is not limited to the above embodiments.

As described above, the satellite broadcasting terrestrial relay apparatus according to the present invention can retransmit downlink satellite signals from multiple satellites to subscribers using one satellite broadcasting relay apparatus through frequency rearrangement, so that the installation is easy and the aesthetics can be improved. Less harm and low complexity. It is also possible to retransmit a plurality of types of polarized signals using one transmission antenna.

1 is a diagram showing the structure of a satellite broadcast relay system to which a satellite broadcast terrestrial relay apparatus according to a first embodiment of the present invention is applied;

FIG. 2 is a block diagram showing an example of a structure of a low noise amplifier included in the satellite broadcast terrestrial repeater shown in FIG.

3A and 3B are cross-sectional views for explaining the structure of a circular waveguide in a transmission antenna that can be applied to the satellite broadcast terrestrial repeater of FIG.

4 is a view for explaining a process of frequency rearrangement by the satellite broadcasting terrestrial repeater according to the first embodiment of the present invention.

5 is a diagram showing the structure of a satellite broadcasting relay system to which a satellite broadcast terrestrial relay apparatus according to a second embodiment of the present invention is applied;

FIG. 6 is a cross-sectional view illustrating a structure of a circular waveguide in a transmission antenna that can be applied to the satellite broadcast terrestrial relay device of FIG. 5. FIG.

7 is a diagram showing the structure of a satellite broadcasting relay system to which a satellite broadcast terrestrial relay apparatus according to a third embodiment of the present invention is applied;

FIG. 8 is a block diagram showing an example of a structure of a low noise amplifier included in the satellite broadcast terrestrial relay shown in FIG.

FIG. 9 is a block diagram illustrating another example of a structure of a low noise amplifier included in the satellite broadcast terrestrial repeater shown in FIG. 7. FIG.

FIG. 10 is a view for explaining a process of rearranging frequencies by a satellite broadcasting terrestrial repeater according to a third embodiment of the present invention; FIG.

Claims (10)

A low noise amplifier for separately amplifying satellite signals received from multiple satellites according to satellites and polarizations, frequency rearranging, synthesizing frequency rearranged signals by polarization, and outputting frequency rearranged polarized signals; And And a transmission antenna unit for receiving the signal output from the low noise amplifier unit and simultaneously retransmitting the frequency rearranged polarization signal to the subscriber side. The low noise amplifier, A plurality of low noise amplifier stages for separately amplifying satellite signals received from multiple satellites according to satellites and polarizations; A frequency rearrangement unit for rearranging the frequency bands of the received satellite signals by mixing the separately amplified satellite signals with signals having a predetermined frequency; A band pass filter for passing only a band of the frequency rearranged signal; And And a synthesizer for synthesizing each signal band for each polarized wave. delete The method of claim 1, wherein the frequency rearrangement unit, A voltage controlled oscillator for outputting an oscillation signal of a predetermined frequency; A frequency multiplier that multiplies the oscillation signal output from the voltage controlled oscillator; And And a mixing unit for shifting the frequency band of the satellite signal by mixing the signal output from the frequency multiplier and the satellite signal. The method of claim 1, wherein the multi-satellite, L-band with 1,525-1,559 MHz, S-band with 2,170-2,200 MHz, C-band with 3,500-4,200 MHz, X-band with 7,250-7,750 MHz, Ku band with 10.95-12.75 GHz, 11.70-12.00 And a satellite using a Ku (DBS) band, a Ka band of 18.10 to 21.20 Hz, and an E band of 19.70 to 21.20 Hz. The method of claim 1, wherein the transmission antenna unit, A first transmission antenna for introducing a signal received through an SMA connector having a first polarized signal port into a circular waveguide through a probe parallel to the ground, and transmitting a radio wave of the first polarized wave; And And a second transmission antenna for transmitting a signal received through the SMA connector having a second polarization signal port into a circular waveguide through a probe perpendicular to the ground, and transmitting a second polarized wave. Ground repeater. The method of claim 5, wherein the first transmission antenna and the second transmission antenna, And a dielectric provided to form a predetermined angle with the ground in the circular waveguide to form a circular polarization. delete A low noise amplifier for separately amplifying satellite signals received from multiple satellites according to satellites and polarizations, frequency rearranging, synthesizing frequency rearranged signals by polarization, and outputting frequency rearranged polarized signals; And And a transmission antenna for receiving the signal output from the low noise amplifier and simultaneously retransmitting the frequency rearranged polarization signal to the subscriber side using one antenna. The low noise amplifier, A plurality of low noise amplifier stages for separately amplifying satellite signals received from multiple satellites according to satellites and polarizations; A frequency rearrangement unit for rearranging the frequency bands of the received satellite signals by mixing the separately amplified satellite signals with signals having a predetermined frequency; A band pass filter for passing only a band of the frequency rearranged signal; And And a synthesizer for synthesizing each signal band for each polarized wave. The transmission antenna, A first SMA connector having a first polarized signal port; A first probe that is level with the ground and introduces a signal received through the first SMA connector into a circular waveguide; A second SMA connector having a second polarized signal port; And And a second probe perpendicular to the ground and for introducing a signal received through the second SMA connector into a circular waveguide. delete The method of claim 8, wherein the transmission antenna, And a dielectric provided to form a predetermined angle with the ground in the circular waveguide to form a circular polarization.