JP2000349675A - Satellite broadcast reception system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a satellite broadcast reception system by which a reception signal of a BS, UHF, VHF and a reception signal of a CS transmitted through one cable are received by a community system. SOLUTION: A CS/BS antenna 1 receives a BS broadcast and a CS broadcast and a right-handed circularly polarized wave converter 2 and a left-handed circularly polarized wave converter 3 receive the broadcast programs. The right-handed circularly polarized wave converter 2 converts a right-handed circularly polarized wave signal of the BS and CS broadcast programs into an intermediate frequency signal and the left-handed circularly polarized wave converter 3 converts the left-handed circularly polarized wave signal of the CS broadcast program into an intermediate frequency signal not in duplicate with the intermediate frequency signal for the BS, CS broadcast programs. A polarized wave mixer 4 mixes the intermediate frequency signals outputted from the right-handed circularly polarized wave converter 2 and the left-handed circularly polarized wave converter 3. Furthermore, a U/V mixer 8 mixes the signals received by a UHF antenna 6 and a VHF antenna 7. A booster 5 amplifies the signals mixed by the polarized wave mixer 4 and the U/V mixer 8 and provides an output of the result to one coaxial cable 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to BS broadcasting / UHF
The present invention relates to a satellite broadcast receiving system that converts signals of different polarizations of broadcast / VHF broadcast and CS broadcast into an intermediate frequency signal, mixes the signals into one coaxial cable, and performs joint reception.

[0002]

2. Description of the Related Art There are two satellites in the same orbit. A first satellite provides service using a first transmission frequency band by, for example, right-handed circular polarization, and a second satellite performs right-handed rotation. And when performing service using the second transmission frequency band with left-handed circular polarization, two antenna devices are basically required to receive radio waves having different polarization systems. I do. For example, in the state where the first satellite, BS broadcasting, provides services using right-handed circularly polarized waves,
Thereafter, when the second satellite (CS) is launched in the same orbit and performs service using right-handed and left-handed circularly polarized waves, two antenna devices are required on the receiving side.

However, in the case of receiving satellite broadcast radio waves arriving from the same direction, installing two antenna devices is troublesome and costly to install, so that it is possible to receive with one antenna. Has been put to practical use. When receiving broadcasts from two satellites as described above, it is common to transmit each received signal to a TV receiver using a different coaxial cable, but recently, as shown below. Various methods of transmitting a received signal using a single coaxial cable have been considered.

(1) In a common reception facility such as an apartment house, since the polarization of the CS broadcast is vertically and horizontally polarized or right-handed or left-handed circularly polarized, the respective polarized signals are locally oscillated. After converting the frequency into an intermediate frequency signal (IF signal) by converters having different frequencies, the signals are mixed and transmitted to a TV receiver via a coaxial cable. In addition, for BS broadcasting, it is mixed with UHF and VHF reception signals and transmitted through another coaxial cable to perform joint reception.

[0005] (2) A block converter for limiting the frequency band of each vertical / horizontal polarized wave or right-handed / left-handed circularly polarized signal of the CS broadcast and converting it to a frequency band higher than the intermediate frequency band of the BS broadcast. And use the converted signal as 1
It transmits through a coaxial cable and performs joint reception.

(3) In a joint reception of a detached house, C
In conjunction with the channel selection of the S tuner, a CS antenna that switches between vertical and horizontal polarized waves of CS broadcasting or circular polarized waves of right and left rotations and outputs to a frequency band higher than the intermediate frequency band of BS broadcasting is used. Then, the switched signal is transmitted through one coaxial cable to perform joint reception.

(4) In the joint reception of a detached house, each signal of vertically and horizontally polarized waves of CS broadcasting or each signal of right and left circularly polarized waves is converted into a frequency band higher than the intermediate frequency band of BS broadcasting. Each signal is input to the polarization switching device that switches the polarization of CS broadcasting in conjunction with the channel selection of the CS tuner using the CS antenna that performs the switching, and the signal selected by the polarization switching device is transmitted through one coaxial cable. To perform joint reception.

[0008]

However, in the method shown in the above (1), since the output signal of the CS broadcast also overlaps with the BS broadcast, the coaxial cable for the CS broadcast and the BS / UHF / V
It is necessary to wire separately from the HF broadcast coaxial cable, which complicates the construction, increases the cost of transmission equipment, and raises the system cost. Also, it is difficult to add a new coaxial cable to an existing system.

Further, the method (2) has a problem in that the receiving frequency band of the CS broadcast is limited, and the receiving channel is limited depending on the CS broadcast service.

In the method described in (3), each signal of the vertical / horizontal polarization or right-handed / left-handed circularly polarized signal of the CS broadcast is switched in conjunction with the channel selection of the CS tuner. There is a problem that when a channel broadcast with a different polarization of CS is selected, a desired channel cannot be received.

Further, in the method described in the above (4), as the number of distribution points of the CS broadcast signal increases, the number of polarization switches used increases, and the existing receiving system uses transmission lines, that is, a television for signal distribution. When terminals are connected in series, there is a problem that a desired CS broadcast channel cannot be received at all locations.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and particularly, when receiving a radio wave of a satellite broadcast arriving from the same direction, a right-handed rotation of a BS broadcast, a UHF broadcast, a VHF broadcast, and a CS broadcast. An object of the present invention is to provide a satellite broadcast receiving system capable of mixing polarized and left-hand circularly polarized signals into one coaxial cable and receiving the signals together.

[0013]

A satellite broadcast receiving system according to a first aspect of the present invention includes a satellite broadcast receiving antenna for receiving a BS broadcast and a CS broadcast, and the same polarization of the BS broadcast and the CS broadcast received by the antenna. A first converter for converting the frequency of each signal into an intermediate frequency signal, and a different polarization signal of the CS broadcast received by the antenna,
A second converter for converting the frequency to an intermediate frequency signal that does not overlap with the CS intermediate frequency signal, and the intermediate frequency signal converted by the first converter and the second converter are mixed and output to one cable. Means.

[0014] A satellite broadcast receiving system according to a second aspect of the present invention includes a satellite broadcast receiving antenna for receiving BS broadcast and CS broadcast, and a BS broadcast and C broadcast received by the antenna.
A first converter for frequency-converting the same polarization signal of the S broadcast into an intermediate frequency signal, and a different polarization signal of the CS broadcast received by the antenna into an intermediate frequency signal which does not overlap with the BS, CS intermediate frequency signal. A second converter for frequency conversion, an intermediate frequency signal converted by the first converter and the second converter, a UHF antenna and V
Mixing means for mixing signals received by the HF antenna and outputting the mixed signals to one cable.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. Figure 1 shows two satellites in the same orbit,
For example, the first satellite (BS) provides service using single circular polarization (right-handed circular polarization), and the second satellite (CS) provides service using right-handed circular polarization and left-handed circular polarization. In this case, the transmission signals of the first satellite (BS) and the second satellite (CS) are received by one antenna device, and the reception signals and the UHF and VHF reception signals are received by one cable. This shows a satellite broadcast receiving system for transmission.

In FIG. 1, reference numeral 1 denotes a CS / BS antenna for receiving a CS broadcast and a BS broadcast. The CS / BS antenna 1 is connected to a right-handed circularly polarized wave converter 2 and a left-handed circularly polarized wave converter 3. You. The right-handed circularly polarized wave converter 2 and the left-handed circularly polarized wave converter 3 convert the right-handed circularly-polarized wave signal and the left-handed circularly polarized wave signal received by the CS / BS antenna 1 into intermediate frequency signals, respectively, and output them. I do. The intermediate frequency signals output from the right-hand circular polarization converter 2 and the left-hand circular polarization converter 3 are mixed by a polarization mixer 4 and input to a booster 5.

Reference numeral 6 denotes a UH receiving a UHF broadcast signal.
F antenna 7 is a VHF antenna for receiving a VHF broadcast signal, and the signals received by both antennas 6 and 7 are U /
They are mixed by the V mixer 8 and input to the booster 5. The booster 5 amplifies the signal mixed by the polarization mixer 4 and the U / V mixer 8 and outputs the amplified signal to one coaxial cable 9. The signal transmitted by the coaxial cable 9 is distributed by the distributor 11 and then transmitted through the TV terminal 12 to the C terminal.
The signal is input to the S / BS / U / V splitter 13.

The CS / BS / U / V splitter 13 splits the input signal into a CS signal and a BS / UHF / VHF signal, inputs the CS signal to a CS tuner 14, and
The UHF / VHF signal is input to the BS / U / V splitter 15. This BS / UV divider 15 converts the input signal to B
The signal is split into an S signal and a UHF / VHF signal, and each of the split signals is input to a TV receiver 16 built in the BS. Further, a signal of the channel selected by the CS tuner 14 is input to the TV receiver 16.

Next, details of the CS / BS antenna 1 will be described with reference to FIG. In FIG. 2, 21 is C
The parabolic reflector of the S / BS antenna 1 includes a vertically polarized wave receiving probe 22 for receiving vertically polarized waves and a horizontally polarized wave receiving probe 23 for receiving horizontally polarized waves. The signal received by the polarization receiving probe 23 is a hybrid polarization separation circuit (90 ° phase shifter)
24. This hybrid polarization separation circuit 24
Generates a right-handed circularly polarized signal and a left-handed circularly polarized signal of the circularly polarized signal based on the signals from the vertical polarization receiving probe 22 and the horizontal polarization receiving probe 23, and converts the right circularly polarized signal to the right. The signal is input to the circularly polarized wave converter 2 and the left circularly polarized wave signal is input to the left circularly polarized wave converter 3.

The right-handed circularly polarized wave converter 2 and the left-handed circularly polarized wave converter 3 convert the received signal into an intermediate frequency signal (IF).
The local oscillation frequency is set so that, for example, the intermediate frequency signal of left-hand circular polarization is higher than the intermediate frequency signal of right-hand circular polarization. For example, if the local oscillation frequency of the right-handed circularly polarized wave converter 2 is 10.678 GHz
z, the local oscillation frequency of the left-hand circularly polarized wave converter 3 is 1
Set to 0.16 GHz.

FIG. 3 shows the right-handed circularly polarized wave converter 2 and the left-handed circularly polarized wave converter 3 in the BS broadcasting and C
It shows an operation example when converting an S broadcast into an intermediate frequency signal. As shown in FIG. 3A, the frequency band (BS (R)) of the right-hand circularly polarized wave of the BS broadcast is 11.71398.
２０12.2013 GHz and has a transmission capacity of 15 transponders. The right-handed circularly polarized wave frequency band (CS (R)) of the CS broadcast is 12.273 to 12.749GH.
z, the frequency band of left-hand circularly polarized wave (CS (L)) is 12.2
53 to 12.729 GHz, each having a transmission capacity of 16 transponders.

The BS broadcast and the CS broadcast are received by the vertical polarization receiving probe 22 and the horizontal polarization receiving probe 23 of the CS / BS antenna 1, and the hybrid polarization separation circuit 24
Is input to This hybrid polarization separation circuit 24
The circularly polarized signal is received by the vertical polarized wave receiving probe 22 and the signal from the vertical polarized wave receiving probe 22 and separated into a right-handed circularly polarized wave and a left-handed circularly polarized signal. The signal is input to the right-handed circular polarization converter 2 and the left-handed circularly polarized signal is input to the left-handed circular polarization converter 3.

The right-handed circularly polarized wave converter 2 has a construction of 10.67.
Perform a frequency conversion operation at a local oscillation frequency of 8 GHz,
As shown in FIGS. 3A and 3C, the right-handed circularly polarized wave “11.7398 to 12.2013 GHz” of the BS broadcast is converted into an intermediate frequency signal of “1035.98 to 1523.3 MHz”. Right-handed circular polarization of CS broadcast "12.273
１２12.749 GHz ”,“ 1595-20
71 MHz ". As described above, since the right-handed circular polarization band of the BS broadcast and the right-handed circular polarization band of the CS broadcast have different frequency bands, the right-handed circular polarization converter 2 uses the same local oscillation frequency to output the intermediate frequency signal. Has been converted to.

The left-hand circularly polarized wave converter 3 has
The frequency conversion operation is performed at the local oscillation frequency of 0.16 GHz, and the left-handed circularly polarized wave of the CS broadcast “12.253 to 12.7”
29 GHz "to an intermediate frequency signal of" 2093 to 2569 MHz ". That is, since the right-hand circular polarization band and the left-hand circular polarization band of the CS broadcast have overlapping frequency bands, different local oscillation frequencies are used and converted into intermediate frequency signals having different frequency bands.

FIG. 3B shows the two local oscillation frequencies of 10.678 GHz and 10.16 GHz.
t) shows components and their harmonics, and the difference between the two local oscillation frequencies is 518 MHz, but the harmonics of 2 to 5 times are “1036”, “1554”, “2072”, and “259”.
0 "MHz, which is a value close to the converted intermediate frequency signal band as shown in FIG. When the harmonics (third-order distortion) of the beat component enter the converted intermediate frequency signal band, they affect the received signal, so that the harmonics of the beat component do not enter the intermediate frequency signal band, and The local oscillation frequencies of the right-handed circularly polarized wave converter 2 and the left-handed circularly polarized wave converter 3 are selected so that the converted intermediate frequency signals do not overlap.

The right-handed circularly polarized intermediate frequency signal converted by the right-handed circularly polarized wave converter 2 and the left-handed circularly polarized intermediate frequency signal converted by the left-hand circularly polarized wave converter 3 are subjected to polarization mixing. The mixture is input to the booster 5. On the other hand, U
The UHF signal received by the HF antenna 6 and the VHF signal received by the VHF antenna 7 are input to the booster 5 after being mixed by the U / V mixer 8. Booster 5
The signal mixed by the polarization mixer 4 and the U / V mixer 8 is amplified and transmitted to the device by one coaxial cable 9. A signal output from the booster 5 to the coaxial cable 9 has a V-band of 90 to 220 MHz as shown in FIG.
HF band, UHF band of 470 to 770 MHz, 1035.
98 to 1523.3 MHz BS (right-handed polarization) band, 15
CS right-handed polarization band of 5-2071 MHz, 2093-25
It is composed of a 69 MHz CS left-handed polarization band signal.

The signal output from the booster 5 to the coaxial cable 9 is distributed by the distributor 11 and
The signal is input to a CS / BS / U / V splitter 13 via a V terminal 12 and split into a CS signal and a BS / UHF / VHF signal. The CS broadcast signal demultiplexed by the CS / BS / U / V demultiplexer 13 is input to a CS tuner 14, an arbitrary channel is selected, sent to a TV receiver 16, and displayed as an image.

The BS / UHF / VHF signal demultiplexed by the CS / BS / U / V demultiplexer 13 is transmitted to the BS / U
The signal is split into a BS signal and a UHF / VHF signal by the V splitter 15 and input to a TV receiver 16 with a built-in BS. The TV receiver 16 selects an arbitrary designated channel and displays an image on the BS broadcast or UHF / VHF broadcast, which is split by the BS / UV splitter 15.

[0029]

As described above in detail, according to the present invention, the same polarization signal of the CS broadcast and the BS broadcast received by the antenna is converted into an intermediate frequency signal by the first converter, and the CS broadcast is different. Since the polarization signal is converted into a high-band intermediate frequency signal which does not overlap with the CS and BS intermediate frequency signals by the second converter, and the respective intermediate frequency signals are mixed by a mixer and output to a cable. , 1
CS broadcasting and BS broadcasting can be transmitted and jointly received by the book cable. Also, according to the present invention, the UHF and VHF signals received by the UHF antenna and the VHF antenna are mixed with the intermediate frequency signals of the CS and BS broadcasts and output. Signals and UHF and VHF broadcast signals can be transmitted and jointly received.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a satellite broadcast receiving system according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing details of a CS / BS antenna part in the embodiment.

FIG. 3 is a view showing a frequency band for explaining a frequency conversion operation in the embodiment.

[Explanation of symbols]

 Reference Signs List 1 CS / BS antenna 2 Right-hand circularly polarized wave converter 3 Left-handed circularly polarized wave converter 4 Polarization mixer 5 Booster 6 UHF antenna 7 VHF antenna 8 U / V mixer 9 Coaxial cable 11 Distributor 12 TV terminal 13 CS / BS / U / V demultiplexer 14 CS tuner 15 BS / U / V demultiplexer 16 TV receiver with built-in BS 21 Parabolic reflector 22 Vertically polarized wave receiving probe 23 Horizontally polarized wave receiving probe 24 Hybrid polarized wave separation circuit

Continued on the front page F term (reference) 5C025 AA22 AA27 BA01 BA25 BA28 DA04 5C064 DA02 DA05 DA08 DA14 5K020 AA02 AA03 AA05 BB04 BB05 BB06 DD12 EE01 EE02 EE16 5K062 AA07 AA08 AA09 AA12 AB11 AC01 AE03

Claims (2)

[Claims] 1. A satellite broadcast receiving antenna for receiving a BS broadcast and a CS broadcast, and a BS received by the antenna.
A first converter for frequency-converting the same polarization signal of broadcasting and CS broadcasting into an intermediate frequency signal, respectively, and a different polarization signal of CS broadcasting received by the antenna,
A second converter for converting the frequency into an intermediate frequency signal that does not overlap with the intermediate frequency signal, and the intermediate frequency signals converted by the first converter and the second converter.
A satellite broadcast receiving system comprising: mixing means for outputting to a book cable. 2. A satellite broadcast receiving antenna for receiving a BS broadcast and a CS broadcast, and a BS received by the antenna.
A first converter for frequency-converting the same polarization signal of broadcasting and CS broadcasting into an intermediate frequency signal, respectively, and a different polarization signal of CS broadcasting received by the antenna,
A second converter for converting the frequency into an intermediate frequency signal that does not overlap with the intermediate frequency signal, and mixing the intermediate frequency signal converted by the first converter and the second converter with the signal received by the UHF antenna and the VHF antenna. A satellite broadcasting receiving system comprising: mixing means for outputting to a single cable.