JP3024970B1 - Relay broadcasting equipment - Google Patents

Abstract

A relay broadcast apparatus capable of relaying received waves of a plurality of channels including received waves of adjacent channels without deteriorating the S / N ratio and IM characteristics. SOLUTION: After a wideband BPF selects received waves of a plurality of channels including a received wave of a target adjacent channel from received waves received, and amplifies the selected waves by a low noise amplifier,
In the distribution / separation means, the received waves of
After further dividing the received wave of each channel by a narrow-band BPF dedicated to each channel and then inputting it to a frequency converter via an isolator, the frequency converter converts the received wave into an intermediate frequency band received wave, The reception wave of each channel is completely separated by the surface acoustic wave filter, and is again converted into the reception wave of the original frequency (or a different frequency) by the frequency converter, and then radiated from the antenna.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relay broadcasting device, and more particularly, to a relay broadcasting device for television broadcasting, mobile radio communication, and the like.

[0002]

2. Description of the Related Art Even if a signal is transmitted from a television transmitting station with stable transmission power, the propagation characteristics of a radio wave fluctuate depending on various conditions such as weather conditions, location conditions, terrain along a route, distance, and height. Generally, a change in the electric field strength under such conditions is called a change due to fading and multipath. It is the relay broadcasting device of the satellite station that receives the radio wave whose electric field strength fluctuates and re-radiates the radio wave at a predetermined output level. FIG. 18 is a block diagram showing a schematic configuration of a conventional relay broadcasting device. Hereinafter, the configuration of a conventional relay broadcasting device will be described along the flow of signals.
A wideband bandpass filter (hereinafter, simply referred to as a BPF) 101 selects a target reception wave of each channel from the received reception waves, and the reception wave of each channel is converted to a high-frequency amplifier circuit 102. Amplified by The high-frequency reception wave amplified by the high-frequency amplification circuit 102 is mixed with the local oscillation signal from the local oscillation circuit 104 by the frequency conversion device 103 and converted into a reception wave in the intermediate frequency band. Are amplified by the intermediate frequency amplifier circuit 105. Next, a BPF that allows only signals of each channel to pass
After passing through 106, the signal is amplified again by the intermediate frequency amplifier circuit 107. The output level of the intermediate frequency amplification circuit 107 is set to a predetermined voltage level by the automatic gain control circuit 108. Next, the reception wave in the intermediate frequency band amplified by the intermediate frequency amplification circuit 107 is mixed with the local oscillation signal from the local oscillation circuit 110 by the frequency conversion device 109 to receive the reception wave of the original frequency (or a different frequency). The power is amplified by the power amplification circuit 111, passes through the low-pass filter 112, reaches the antenna, and is transmitted from the antenna.

[0003]

In recent years, in addition to the conventional analog television broadcasting, digital television broadcasting is about to start due to advances in technology. However, when digital television broadcasting is transmitted in addition to analog television broadcasting, digital television broadcasting-digital television broadcasting, There is a need for television broadcasting using adjacent channels, such as television broadcasting of a system-digital television broadcasting. However,
An extremely narrow band BPF that allows only signals of each channel to pass through from among television signals including adjacent channels cannot be realized. Therefore, in the conventional relay broadcasting apparatus shown in FIG. By
There is a problem that the S / N ratio or IM (intermodulation wave) characteristics are deteriorated. SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and an object of the present invention is to convert received waves of a plurality of channels, including received waves of adjacent channels, into S / N ratios, IM (mutual interference) signals. It is an object of the present invention to provide a relay broadcasting device capable of relaying without deteriorating (modulated wave) characteristics. The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0004]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows. That is, the present invention provides a broadband pass filter that passes received waves of a plurality of channels including adjacent channels, a low noise amplifier that amplifies received waves of a plurality of channels that have passed through the wideband pass filter, and an amplifier that is amplified by the low noise amplifier. A splitter that splits the received waves of the plurality of channels into two, and a plurality of separating units provided for each of the plurality of channels, so that the received waves of the plurality of channels output from one output terminal of the splitter A group of separating means for separating the reception waves of the odd-numbered (or even-numbered) channels from the reception waves of the even-numbered (or odd-numbered) channels from the reception waves of the plurality of channels output from the other output terminal of the distributor. A plurality of separating means each including a separating means group for separating the received wave of each channel; and the received waves for each channel separated by the separating means are supplied to the antenna sharing apparatus. And a splitter, wherein each of the splitters receives an odd-numbered (or even-numbered) channel received wave output from one output terminal of the two-way splitter, or the two-way splitter. A narrow band-pass filter for passing a reception wave of an even-numbered (or odd-numbered) channel output from the other output terminal of the filter, an isolator for passing a reception wave passed through the narrow band-pass filter, and the isolator. First frequency conversion means for converting the frequency of the received wave passed therethrough, surface acoustic wave filter for passing the reception wave frequency-converted by the first frequency conversion means, and frequency conversion for passing the surface acoustic wave filter An amplifier for amplifying the received wave of each channel, and a frequency conversion of the frequency-converted received wave of each channel amplified by the amplifier. And having a second frequency conversion means that. Further, the present invention provides a wide band pass filter that passes received waves of a plurality of channels including an adjacent channel, a low noise amplifier that amplifies the received waves of a plurality of channels that have passed through the wide band pass filter, and an amplifier amplified by the low noise amplifier. Distribution means for distributing the received waves of the plurality of channels to the number of channels of the plurality of channels, and a plurality of separation means provided for each of the plurality of channels, wherein the reception waves of the plurality of channels output from the distribution means A relay broadcast apparatus comprising: a plurality of separating units that separate received waves of each channel from among them; and an output unit that supplies a received wave of each channel separated by each of the separating units to an antenna sharing apparatus, Each of the separation means passes through a narrow band-pass filter for passing a plurality of channels of reception waves output from the distribution means, and the narrow band-pass filter. An isolator that passes the received wave, a first frequency conversion unit that converts the frequency of the reception wave that has passed through the isolator, and a surface acoustic wave filter that passes the reception wave that has been frequency-converted by the first frequency conversion unit. An amplifier for amplifying the frequency-converted received wave of each channel that has passed through the surface acoustic wave filter, and a second frequency for frequency-converting the frequency-converted received wave of each channel amplified by the amplifier Conversion means. Also, the present invention provides a method according to the present invention, wherein each of the separation means includes an attenuator inserted between a narrow band-pass filter and a first frequency conversion means, and a reception wave of each frequency-converted channel amplified by the amplifier. Gain control means for controlling the attenuator on the basis of the above, and controlling the voltage level of the frequency-converted received wave of each channel amplified by the amplifier.

[0005]

Embodiments of the present invention will be described below in detail with reference to the drawings. In all the drawings for describing the embodiments, components having the same functions are denoted by the same reference numerals, and repeated description thereof will be omitted. [First Embodiment] FIG. 1 is a block diagram showing a schematic configuration of a relay broadcast apparatus according to an embodiment of the present invention. As shown in the figure, in the relay broadcast device of the present embodiment, the broadband BP
By F (1), a desired one of the received waves of a plurality of channels is selected from the received waves, and the received waves of the plurality of channels are separated by the hybrid circuit (2, 4) into two connected waves. The signal is amplified by the low noise amplifiers (3a, 3b). In addition, the received waves of the plurality of channels are orthogonal frequency division multiplexed (OFDM;
Orthogonal Frequency Divi
The signal includes a modulated wave (hereinafter, referred to as an OFDM wave) of a son multiplex modulation method and a received wave of an adjacent channel. In addition, two low noise amplifiers (3
Reference numerals a and 3b) denote two-stage amplifier circuits each including an amplifier circuit 12 at the first stage and an amplifier circuit 13 at the subsequent stage. Further, the broadband BPF (1), the hybrid circuit (2, 4),
The two low noise amplifiers (3a, 3b) are provided under the antenna of the satellite station, and the two low noise amplifiers (3a, 3b) are provided.
a, 3b) is supplied with a power supply voltage (DC) via low-pass filters (8a, 8b). The reception waves of a plurality of channels amplified by the two low-noise amplifiers (3a, 3b) are input to distribution / separation means 5, and the reception waves output from distribution / separation means 5 are transmitted to antenna duplexer 6. It is input and transmitted from the two-aperture antenna 7. In FIG. 1 and each of the drawings described later, reference numeral 9 denotes a non-reflection terminator.
10a to 10e are output BPFs, and 11 is a hybrid circuit. The distributing / separating means 5 and the duplexer 6 are provided in a satellite station. In addition,
In the relay broadcasting device, if the noise (NF) characteristic is reduced by the transmission loss of the cable, the low noise amplifier (3a, 3b) may be provided in the satellite station.

FIG. 2 is a block diagram showing the configuration of the distribution / separation means 5 shown in FIG. As shown in FIG. 2, the reception waves of a plurality of channels amplified by the two low noise amplifiers (3a, 3b) are combined with a hybrid circuit (a distributor of the present invention) 51.
Is divided into two. The hybrid circuit 51 is connected to a narrow band B dedicated to each channel via a circulator 52.
Input to PFs (53a-53e). Here, a narrow band BPF dedicated to each odd-numbered (or even-numbered) channel
(53a, 53c, 53e) correspond to the hybrid circuit 51.
Connected to one terminal of the even number (or odd number)
Narrow band BPF (53b, 53d) dedicated to each channel
Is connected to the other terminal of the hybrid circuit 51.
The circulator 52 inserted between the hybrid circuit 51 and the narrow-band BPF (53a to 53e) dedicated to each channel includes a narrow-band BPF (53a dedicated to each channel).
53e) is prevented from being input to the hybrid circuit 51. The received waves of the plurality of channels are temporarily separated by the narrow band BPFs (53a to 53e) dedicated to each channel, and then input to the separating means 54 dedicated to each channel. The temporarily separated reception waves of the respective channels are mixed in the frequency converter 62 with the local oscillation signal from the local oscillator 65 and converted into reception waves in the intermediate frequency band. Completely separated. The received wave in the intermediate frequency band completely separated by the surface acoustic wave filter 63 is amplified by an amplifier 64 and then mixed with a local oscillation signal from a local oscillator 65 in a frequency converter 66 to obtain the original frequency ( After that, the power is amplified by the power amplifier 68. Also,
An attenuator 61 composed of a pin diode is provided at an input stage of the frequency converter 62, and the attenuator 61 is controlled by an automatic gain control circuit 67. The automatic gain control circuit 67 receives the output from the amplifier 64 and controls the attenuator 61 so that the voltage level of the received wave in the intermediate frequency band output from the amplifier 64 becomes constant. The circulator (isolator of the present invention) 52 inserted between the narrow band BPFs (53a to 53e) dedicated to each channel and the separating means 54 dedicated to each channel includes a local oscillator signal from a local oscillator 65, The reflected wave from the frequency converter 62 is
F (53a-53e) is prevented from being input. In addition,
In the present embodiment, it is possible to obtain 35 dB as the gain (G) of the received wave of each channel obtained from each separating means 54.

Hereinafter, the configuration of each part of the present embodiment will be described in more detail. Broadband BPF shown in FIG.
(1) 30 dB at a frequency 6 MHz away from band ET by passing the target reception waves of a plurality of channels.
This is a BPF that attenuates as described above. The main functions of the BPF (1) are as follows. (1) Passing a desired reception signal of a plurality of adjacent channels (for example, TV reception signals (6 to 10 CH)), and transmitting other unnecessary waves such as a television and a mobile phone at 470 MHz.
The following signals for wireless communication and the like are attenuated. (2) Narrow band BPFs (53a-53) dedicated to each channel
In e), the amount of attenuation is insufficient.
Image frequency (fo-2fi or fo + 2fi)
Signal is attenuated. (3) Absorb lightning surges and the like induced by receiving antennas and the like. As described above, the wideband BPF (1) cannot be realized unless it is a comb-line or interdigital band-pass filter having an order (n) of 8 because the passband is wide and the attenuation is steep. FIG. 3 shows a broadband BP according to the present embodiment.
FIG. 4 is a graph showing an example of frequency characteristics of F (1). A broadband BPF (1) shown in FIG. 3 is a comb-line or interdigital band-pass filter having an order (n) of 8, and has no load. Q (Qu) is 2200, passband (Bw
r) is 66 MHz, attenuation near the pass band (Amin)
Is 35 dB. The broadband BPF shown in FIG.
(1) means that the size is width (W) 100 × length (L) 20
0 × height (H) is 150 mm.

As a general low-noise amplifier, a low-noise amplifying element having a small receiving intercept point (IP) is used. When a low-noise amplifier using this type of hatching element is used for amplifying an OFDM wave, an IM wave (intermodulation wave) is generated, leading to a decrease in reception quality. It is said that the reason is that the peak power of the OFDM wave is about 10 dB higher than that of the carrier wave (including the modulated wave) used for general communication and broadcasting. The amount of wave degradation will be about 30 dB worse. further,
By simultaneously amplifying eight OFDM waves simultaneously,
The IM characteristic is reduced by about 18 dB. Therefore, as in the present embodiment, the low-noise amplifiers (3a, 3b) that amplify the received waves of a plurality of channels including the OFDM wave have a smaller size than a low-noise amplifier used for general communication and broadcasting. It is necessary to use an amplifying element having a good IM characteristic of about 48 dB. In the low noise amplifier (3a, 3b) of the present embodiment, an output (transmission) MOS transistor (FET) is used as an amplifying element.
Among them, an element having good (low) noise (NF) characteristics and high gain (Gain) is selected and used. By using the selected MOS transistors (FETs) and using a two-stage amplifier circuit as shown in FIG. 1, the low-noise amplifiers 3a and 3b of the present embodiment can (NF) {1dB, gain (G)}
40dB, Intersect Point (IP) @ 38dBm
Is obtained. Further, as shown in FIG. 1, in the case of a two-parallel configuration in which the failure rate has redundancy, the overall characteristics are noise (NF) ≒ 1 dB, gain (G) ≒ 40 dB, and intersect point (IP ) A characteristic of $ 41 dBm is obtained. FIGS. 4 to 6 show graphs of the IM characteristics of the noise amplifiers (3a, 3b) of the present embodiment. FIG. 4 is a graph showing the IM characteristics of the first-stage amplifier circuit 12 shown in FIG. 1. The horizontal axis represents input power (unit: dBm), and the vertical axis represents output voltage (unit: dBm). In FIG. 4, a straight line F
Represents the input-output voltage characteristic of the fundamental wave, and the straight line T represents the third-order I
It shows the input-output voltage characteristic of the M wave, and when the input power is at the same power level, the larger the difference between the straight line F and the straight line T (that is, the difference in output power), the better the third-order IM characteristic. Generally, the higher the intersect point (IP), the better the third-order IM characteristics. FIG. 5 is a graph showing the IM characteristics of the latter-stage amplifier circuit 13 shown in FIG. 1, and FIG. 6 is a graph showing the IM characteristics when two low-noise amplifiers (3a, 3b) are configured in parallel.

FIGS. 7 to 10 are graphs showing frequency characteristics of an example of narrow-band BPFs (53a to 53e) dedicated to each channel according to the present embodiment. FIG. 7 is a graph showing the attenuation characteristics. The horizontal axis indicates the frequency (MHz) and the memory interval is 2 MHz (the center frequency is 485 MHz), and the vertical axis indicates the attenuation (dB) and the memory interval is 5 dB. FIG.
Is a graph showing the graph shown in FIG. 7 in an enlarged manner, and the memory interval on the vertical axis is 1 dB. FIG. 9 is a graph showing the reflection characteristics. The horizontal axis represents the frequency (MHz) and the memory interval is 2 MHz, and the vertical axis represents the attenuation (dB) and the memory interval is 5 dB. FIG. 10 is a graph showing the group delay time characteristic, where the horizontal axis represents the frequency (MHz) and the memory interval is 2M.
Hz, the vertical axis is the delay amount (τ), and the memory interval is 50n.
s. 11 to 14 are graphs showing frequency characteristics of another example of the narrow band BPF (53a to 53e) dedicated to each channel according to the present embodiment. FIG. 11 is a graph showing the attenuation characteristics. The horizontal axis represents the frequency (MHz), the memory interval is 2 MHz (the center frequency is 485 MHz),
The vertical axis represents the attenuation (dB), and the memory interval is 10 dB.
FIG. 12 is a graph showing the graph shown in FIG. 11 in an enlarged manner. The memory interval on the horizontal axis is 1 MHz, and the memory interval on the vertical axis is 1 dB. FIG. 13 is a graph showing the reflection characteristics. The horizontal axis represents the frequency (MHz) and the memory interval is 2 MHz, and the vertical axis represents the attenuation (dB) and the memory interval is 5 dB. FIG. 14 is a graph showing the group delay time characteristic, where the horizontal axis represents the frequency (MHz) and the memory interval is 1 MHz.
The vertical axis represents the delay amount (τ) and the memory interval is 100 ns.
The BPF shown in FIGS. 7 to 14 is a comb-line or interdigital band-pass filter having an order (n) of 4 and has a size of width (W) 200 × length (L).
200 × 150 mm in height (H). FIG. 15 shows the BP
5 is a graph showing the amount of IM degradation depending on the frequency at the 20 dB attenuation point of F. The horizontal axis represents the difference between the center frequency (fo) and the frequency at which the attenuation amount becomes 20 dB, and the vertical axis represents the IM degradation amount (d).
B). As shown in FIG. 15, by selecting the attenuation characteristic of the BPF, the IM deterioration amount can be reduced to a practical value. For example, in the case of a BPF attenuated by about 20 dB at a center frequency (fo) ± 4.5 MHz like the BPFs shown in FIGS. 7 to 14, the IM degradation amount is calculated from the graph shown in FIG. About 1.
5 dB. As an input filter (BPF) used in a conventional satellite station, a center frequency (fo) ± 9M
A BPF that attenuates by 20 dB at Hz is used. However, according to the characteristics of the BPF, only 50% of unnecessary wave energy of both adjacent channels can be removed. Further, in a BPF that attenuates about 20 dB at a center frequency (fo) ± 9 MHz, such as an input filter (BPF) used in a conventional satellite station, the amount of degradation of IM is determined by the graph shown in FIG. Is about 6 dB. As described above, the narrow-band BPF (5
In 3a to 53e), the deterioration amount of the IM can be reduced. If the attenuation characteristic and the pass band width of the BPF fluctuate, the frequency characteristic and the IM characteristic deteriorate. Therefore, the narrow band BPF (53a to 53
In e), Super Invar is used as a constituent material to stabilize the BPF. In order to prevent leakage of a local oscillation signal from the local oscillator 65, one of the design techniques is to increase the order of the BPF. However, as the BPF increases, the deviation in the pass band increases, and the BPF characteristic deteriorates. Not preferred. Therefore, the circulator 52 inserted between the narrow band BPFs (53a to 53e) dedicated to each channel and the separating means 54 dedicated to each channel is inserted.

In the present embodiment, the frequency converter 6
2, an attenuator 61 composed of a pin diode that generates less IM waves is inserted before the frequency converter (6).
2, 66), a frequency conversion circuit having good third-order IM characteristics is used, so that deterioration of the IM characteristics can be reduced. In this embodiment, when leakage of the local oscillation signal from the frequency converter 66 becomes a problem,
A notch filter that removes only the local oscillation signal may be used.

[Second Embodiment] FIG. 16 is a block diagram showing a schematic configuration of a relay broadcast apparatus according to a second embodiment of the present invention. The relay broadcasting apparatus according to the present embodiment is different from the above-described embodiment in the configuration of the distribution / separation unit 15, but the other configuration is the same as the above-described embodiment. Hereinafter, the relay broadcasting apparatus of the present embodiment will be described focusing on the differences from the above-described embodiment. FIG. 17 is a block diagram showing a configuration of the distribution / separation unit 15 shown in FIG. As shown in FIG. 17, in the present embodiment, received signals of a plurality of channels amplified by two low-noise amplifiers (3a, 3b) by hybrid circuits (dividers of the present invention) (71 to 77). ,
It is distributed to the number of channels (8 in the present embodiment), and a narrow band BPF (53a to 53h) dedicated to each channel and a separating means 54 dedicated to each channel are connected to each output terminal of the hybrid circuit (74 to 77). It is something to do. In the present embodiment, it is possible to obtain 29 dB as the gain (G) of the received wave of each channel obtained from each separating means 54.

In this embodiment, as in the above-described embodiment, the amount of deterioration of the IM characteristics can be reduced.
As described above, the invention made by the inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and can be variously modified without departing from the gist of the invention. Of course, it is.

[0013]

The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows. According to the present invention, for example, a received signal of a plurality of channels including a modulated wave of a digital television broadcast and a received wave of an adjacent channel is converted into an S / N signal.
Relaying can be performed without deteriorating the ratio and IM characteristics.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a relay broadcast device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a distribution / separation unit 5 shown in FIG.

FIG. 3 is a graph illustrating frequency characteristics of an example of the wideband bandpass filter according to the present embodiment.

FIG. 4 is a graph showing IM characteristics of the first-stage amplifier circuit shown in FIG. 1;

FIG. 5 is a graph showing IM characteristics of the subsequent-stage amplifier circuit shown in FIG. 1;

FIG. 6 is a graph showing IM characteristics when two low-noise amplifiers are configured in parallel.

FIG. 7 is a graph illustrating an attenuation characteristic of an example of a narrow band pass filter dedicated to each channel according to the first embodiment of the present invention.

FIG. 8 is an enlarged graph showing the graph shown in FIG. 7;

FIG. 9 is a graph showing reflection characteristics of an example of a narrow-band bandpass filter dedicated to each channel according to the first embodiment of the present invention.

FIG. 10 is a graph showing group delay time characteristics of an example of a narrowband bandpass filter dedicated to each channel according to the first embodiment of the present invention.

FIG. 11 is a graph showing an attenuation characteristic of another example of the narrowband bandpass filter dedicated to each channel according to the first embodiment of the present invention.

FIG. 12 is an enlarged graph showing the graph shown in FIG. 11;

FIG. 13 is a graph showing reflection characteristics of another example of the narrowband bandpass filter dedicated to each channel according to the first embodiment of the present invention.

FIG. 14 is a graph showing group delay time characteristics of another example of the narrowband bandpass filter dedicated to each channel according to the first embodiment of the present invention.

FIG. 15 is a graph showing the relationship between I and BPF at a frequency of 20 dB attenuation;
It is a graph which shows M degradation amount.

FIG. 16 is a block diagram illustrating a schematic configuration of a relay broadcast device according to a second embodiment of the present invention.

FIG. 17 is a block diagram illustrating a configuration of a distribution / separation unit illustrated in FIG. 16;

FIG. 18 is a block diagram showing a schematic configuration of a conventional relay broadcasting device.

[Explanation of symbols]

1,101 ... Broadband bandpass filter, 2,4,11,
51, 71 to 77: hybrid circuit, 3a, 3b: low noise amplifier, 5: distributing / separating means, 6: antenna duplexer, 7: two-aperture antenna, 8a, 8b, 12: low-pass filter, 9: non-reflection Terminators, 10a to 10h: output band-pass filters, 12, 13: amplifier circuits, 52: circulators, 53a to 53h, 106: narrow-band band-pass filters dedicated to each channel, 54: separating means dedicated to each channel, 61 ... attenuator consisting of pin diode, 6
2, 66, 103, 109: frequency converter, 63: surface acoustic wave filter, 64, 105, 107: amplifier, 6
5, 110 local oscillator, 67, 108 automatic gain control circuit, 68, 111 power amplifier, 102 high frequency amplifier circuit, 112 antenna.

Claims (4)

(57) [Claims] A broadband pass filter that passes received waves of a plurality of channels including adjacent channels; a low noise amplifier that amplifies received waves of a plurality of channels that have passed through the wideband pass filter; A distributor for dividing the received waves of the plurality of channels into two, and a plurality of separating means provided for each of the plurality of channels, from among the received waves of the plurality of channels output from one output terminal of the distributor. A separating means group for separating the reception waves of each odd-numbered (or even-numbered) channel, and each of the even-numbered (or odd-numbered) signals among the reception waves of a plurality of channels output from the other output terminal of the distributor. A plurality of separating means each including a separating means group for separating a received wave of a channel; and a receiving wave for each channel separated by each of the separating means is supplied to an antenna sharing apparatus. And an output unit that performs the splitting operation, wherein each of the separation units receives a reception wave of an odd-numbered (or even-numbered) channel output from one output terminal of the two-way splitter, or the two-way splitter. A narrow-band-pass filter for passing a reception wave of an even-numbered (or odd-numbered) channel output from the other output terminal of the filter, an isolator for passing a reception wave passed through the narrow-band-pass filter, and the isolator First frequency conversion means for converting the frequency of the received wave that has passed therethrough, surface acoustic wave filter that allows the reception wave frequency-converted by the first frequency conversion means to pass, and frequency conversion that has passed the surface acoustic wave filter An amplifier that amplifies the received wave of each channel obtained by the above-described process, and a frequency-converted received wave of each channel that has been amplified by the amplifier. And a second frequency converting means for changing the frequency. 2. A wide band pass filter for passing received waves of a plurality of channels including an adjacent channel, a low noise amplifier for amplifying received waves of a plurality of channels passing through the wide band pass filter, and an amplifier amplified by the low noise amplifier. Distribution means for distributing the received waves of a plurality of channels to the number of channels of the plurality of channels, and a plurality of separating means provided for each of the plurality of channels; A plurality of separating means for separating the received wave of each channel from, and an output means for supplying the received wave for each channel separated by each of the separating means to the antenna sharing apparatus, wherein the relay broadcast device, Separating means for passing a plurality of channels of reception waves output from the distributing means through a narrow band-pass filter; An isolator that passes the passed reception wave; a first frequency conversion unit that converts the frequency of the reception wave that has passed through the isolator; a surface acoustic wave filter that passes the reception wave that has been frequency-converted by the first frequency conversion unit An amplifier for amplifying the frequency-converted received wave of each channel that has passed through the surface acoustic wave filter; and a second frequency-converting the frequency-converted received wave of each channel amplified by the amplifier. A relay broadcast device comprising: frequency conversion means. 3. Each of the separating means includes an attenuator inserted between a narrow band-pass filter and a first frequency converting means, and an attenuator inserted into the frequency-converted reception wave amplified by the amplifier. 3. A gain control means for controlling the attenuator based on the gain and controlling a voltage level of a received wave of each frequency-converted channel amplified by the amplifier. 3. The relay broadcasting device according to 1. 4. The relay broadcasting device according to claim 3, wherein the attenuator is configured by a pin diode.