JP2021040291A - Down-converter, up-converter, and receiving system - Google Patents

Abstract

To allow viewing of an arbitrarily selected physical channel broadcast of a left-handed circularly polarized satellite broadcast wave without the need for major modifications to a receiving system.SOLUTION: A down-converter includes a first DIP switch, a first frequency converter, and a first control circuit. In the first DIP switch, whether to down-convert a first broadcast signal included in a received signal of a left-handed circularly polarized satellite broadcast wave to a second broadcast signal in a CATV band is set for each first broadcast signal. The first frequency converter extracts the first broadcast signal from the received signal and down-converts the first broadcast signal into the second broadcast signal. The first control circuit controls the first frequency converter on the basis of the setting in a first DIP switch. The first frequency converter down-converts the first broadcast signal which is set to be down-converted by the first dip switch to the second broadband signal of the second transmission frequency band associated with the first transmission frequency band of the first broadcast signal in a predetermined correspondence relationship.SELECTED DRAWING: Figure 2

Description

The present invention relates to downconverters, upconverters, and receiving systems.

Conventionally, in a receiving system installed in a building such as a building or an apartment, satellite broadcasting waves such as BS and CS received by a common satellite broadcasting antenna are converted into intermediate frequency signals, mixed and distributed, and each dwelling unit. (See, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2004-200875

By the way, from 2018, practical broadcasting of left-handed circularly polarized satellite broadcasting waves capable of providing 4K or 8K ultra-high-definition images has started. To receive left-handed circularly polarized satellite broadcast waves, a receiving antenna dedicated to left-handed circularly polarized satellite broadcast waves or a receiving antenna compatible with right-left circularly polarized satellite broadcast waves is required, but not only that, Refurbishment of the receiving system may also be required. For example, the transmission frequency band (2224 to 2634 [MHz] and 2748 to 3224 [MHz]) of the intermediate frequency signal output from the receiving antenna corresponding to the satellite broadcasting wave of left-handed circularly polarized wave has a high frequency, so that the transmittable distance is Is short. Therefore, there is a high possibility that it will be necessary to provide a plurality of boosters for signal amplification between the intermediate frequency signal distributor and the TV tuner of each dwelling unit.

In addition, some physical channels of left-handed circularly polarized satellite broadcast waves are arbitrarily selected, and the intermediate frequency signals of each physical channel are down-converted to a lower transmission frequency band for distribution and transmission, and each dwelling unit. It is also conceivable to up-convert and supply to the TV tuner. However, in this case, when up-converting, it is necessary to know which physical channel's intermediate frequency signal is down-converted to which transmission frequency band. Therefore, conventionally, the down converter provided in front of the distributor communicates with the up converter of the distribution destination installed in each dwelling unit, and the selected physical channel and the transmission frequency band obtained by down-converting the physical channel are used. Needed to be notified to the upconverter. Therefore, there was a high possibility that a major renovation of the receiving system would be required, such as adding a communication cable.

In view of the above situation, it is an object of the present invention to make it possible to watch a broadcast of an arbitrarily selected physical channel of a satellite broadcast wave of left-handed circularly polarized waves without requiring a major modification of the receiving system.

In order to achieve the above object, whether or not the down converter according to one aspect of the present invention downconverts the first broadcast signal included in the received signal of the left-handed circularly polarized satellite broadcast wave to the second broadcast signal in the CATV band. A first dip switch set for each of the first broadcast signals, a first frequency conversion unit that extracts the first broadcast signal from the received signal and down-converts it to the second broadcast signal, and the first. The first control circuit for controlling the first frequency conversion unit based on the setting of the dip switch, and the first frequency conversion unit is set to be down-converted by the first dip switch. A configuration (first configuration) in which a broadcast signal is down-converted to the second broadcast signal of the second transmission frequency band associated with the first transmission frequency band of the first broadcast signal in a predetermined correspondence relationship. Will be done.

In the down converter having the first configuration, the satellite broadcast wave may have a configuration (second configuration) including a left-handed circularly polarized BS broadcast wave and a left-handed circularly polarized CS broadcast wave. ..

In the down converter having the first or second configuration, the first transmission frequency band of the first broadcast signal set to be down-converted by the first dip switch has a frequency from the smallest first transmission frequency band, respectively. The configuration may be such that the second transmission frequency band is associated with the second transmission frequency band in ascending order from the smallest frequency (third configuration).

In the down converter having any of the first to third configurations, the number of the first broadcast signals down-converted by the first frequency converter is smaller than the number of switches of the first DIP switch (the number of switches is smaller than that of the first DIP switch. The fourth configuration) may be used.

In the down converter having the fourth configuration, the number may be 12 or 8 (fifth configuration).

In order to achieve the above object, the upconverter according to one aspect of the present invention receives a transmission signal from the downconverter according to any one of the first to fifth configurations, and has a CATV band included in the transmission signal. A second dip in which the second broadcast signal is up-converted to the first broadcast signal of a left-handed circularly polarized satellite broadcast signal, and the first broadcast signal up-converted from the second broadcast signal is set. A switch, a second frequency conversion unit that up-converts the second broadcast signal to the first broadcast signal, and a second control circuit that controls the second frequency conversion unit based on the settings of the second dip switch. , And the first transmission frequency band of the first broadcast signal set to be up-converted by the second dip switch is the second transmission frequency of the second broadcast signal in a predetermined correspondence relationship. The second frequency conversion unit is associated with a band, and has a configuration (sixth configuration) of up-converting the second broadcast signal to the first broadcast signal based on the correspondence.

In order to achieve the above object, the receiving system according to one aspect of the present invention includes a converter having any one of the first to fifth configurations and a receiving device having the sixth configuration (the first). 7 configuration).

According to the present invention, it is possible to make it possible to watch a broadcast of an arbitrarily selected physical channel of a satellite broadcast wave of left-handed circularly polarized waves without requiring a major modification of the receiving system.

It is a conceptual diagram which shows the configuration example of a receiving system. It is a figure for demonstrating the transmission example of the satellite broadcast wave in a receiving system. It is a block diagram which shows the configuration example of the down converter. It is a block diagram which shows the structural example of the left-handed frequency conversion part. It is a block diagram which shows the configuration example of an upconverter. It is a block diagram which shows the structural example of the CATV frequency conversion part. It is a figure for demonstrating the 1st modification of the transmission of the satellite broadcast wave in a receiving system. It is a figure for demonstrating the 2nd modification of the transmission of the satellite broadcast wave in a receiving system.

An embodiment of the present invention will be described below with reference to the drawings.

<1. Embodiment>
<1-1. Receiving system ＞
The receiving system 100 is installed in a building such as a building or a condominium. FIG. 1 is a conceptual diagram showing a configuration example of the receiving system 100. FIG. 2 is a diagram for explaining an example of transmission of satellite broadcast waves in the reception system 100.

As shown in FIG. 1, a satellite dish receiving antenna 201 and a terrestrial broadcasting receiving antenna 202 are connected to the receiving system 100.

The satellite dish receiving antenna 201 receives the satellite broadcast wave, converts it into an intermediate frequency signal (hereinafter, referred to as an IF signal), and outputs the signal. That is, this IF signal is a reception signal output by the satellite broadcast reception antenna 201. The satellite broadcasting wave includes a BS (broadcasting satellite) broadcasting wave and a CS (communication satellite) broadcasting wave. Further, the BS broadcast wave and the CS broadcast wave include a right-handed circularly polarized broadcast wave and a left-handed circularly polarized broadcast wave, respectively. In the following, a right-handed circularly polarized BS broadcast wave will be referred to as a BS right-handed broadcast wave, and a right-handed circularly polarized CS broadcast wave will be referred to as a CS right-handed broadcast wave. Further, a BS broadcast wave with left-handed circularly polarized waves is called a BS left-handed broadcast wave, and a CS broadcast wave with left-handed circularly polarized waves is called a CS left-handed broadcast wave.

The BS right-handed broadcast wave has 12 physical channels BS1ch to 23ch. Further, as shown in FIG. 2, the BS left-handed broadcast wave has 12 physical channels BS2ch to 24ch. The center frequency interval of each physical channel of the BS right-handed broadcast wave and the BS left-handed broadcast wave is 38.36 [MHz], and the occupied frequency width of each physical channel is 34.5 [MHz]. In the present embodiment, the BS right-handed broadcast wave is converted into an IF signal having a frequency band of 1032 to 1489 [MHz] by the satellite broadcast receiving antenna 201 and output. Further, the BS left-handed broadcast wave is converted into an IF signal having a frequency band of 2224 to 2681 [MHz] by the satellite dish receiving antenna 201 and output.

The CS right-handed broadcast wave has 12 physical channels CS2ch to 24ch. In FIG. 2, the physical channel of the CS right-handed broadcast wave is not shown. Further, as shown in FIG. 2, the CS left-handed broadcast wave has 13 physical channels CS1ch to 25ch. The center frequency interval of each physical channel of the CS right-handed broadcast wave and the CS left-handed broadcast wave is 40 [MHz], and the occupied frequency width of each physical channel is 34.5 [MHz]. In the present embodiment, the CS right-handed broadcast wave is converted into an IF signal having a frequency band of 1595 to 2071 [MHz] by the satellite broadcast receiving antenna 201 and output. Further, the CS left-handed broadcast wave is converted into an IF signal having a frequency band of 2748 to 3224 [MHz] by the satellite broadcast receiving antenna 201 and output.

These IF signals are included in the received signal output from the satellite dish receiving antenna 201.

In the present embodiment, the satellite dish receiving antenna 201 can receive both a right-handed circularly polarized satellite dish and a left-handed circularly polarized satellite dish. However, the present invention is not limited to this example, and instead of the satellite dish receiving antenna 201, a receiving antenna dedicated to a right-handed circularly polarized satellite dish and a receiving antenna dedicated to a left-handed circularly polarized satellite dish are used as a receiving system. Each may be connected to 100.

The terrestrial broadcast receiving antenna 202 receives and outputs a terrestrial digital broadcast wave.

The reception system 100 generates a transmission signal including a broadcast signal of the satellite broadcast wave output from the satellite broadcast reception antenna 201 and a reception signal of the terrestrial digital broadcast wave output from the terrestrial broadcast reception antenna 202. At this time, among the broadcast signals of the satellite broadcast waves, the first broadcast signals of some physical channels of the BS left-handed broadcast wave and the CS left-handed broadcast wave have transmission frequency bands of 118 to 424 [MHz] and 769 to 923 [MHz. ] Is down-converted to the second broadcast signal in the CATV band. The receiving system 100 distributes the generated transmission signal and supplies it to each dwelling unit.

The receiving system 100 includes a down converter 1, a booster 101, a distributor 102, and a plurality of up-converting systems 300.

A satellite broadcast receiving antenna 201 and a terrestrial broadcast receiving antenna 202 are connected to the down converter 1, and a satellite broadcast wave reception signal and a terrestrial digital broadcast wave reception signal are input. The down converter 1 outputs a transmission signal obtained by mixing a broadcast signal of a satellite broadcast wave and a reception signal of a terrestrial digital broadcast wave to the booster 101. At this time, the down converter 1 extracts left-handed circularly polarized satellite broadcast waves (BS left-handed broadcast wave and CS left-handed broadcast wave) from the received signal of the satellite broadcast wave, and is included in the left-handed circularly polarized satellite broadcast wave. The first broadcast signal of the unit is down-converted to the second broadcast signal of the CATV band and output to the booster 101. The configuration of the down converter 1 will be described later.

The booster 101 amplifies the transmission signal input from the down converter 1 and outputs it to the distributor 102.

The distributor 102 distributes the transmission signal input from the booster 101 and supplies the transmission signal to the up-conversion system 300 installed in each dwelling unit.

Next, in each dwelling unit, the up-conversion system 300 is connected to the TV receiver 402 via the tuner 401. The up-conversion system 300 includes a booster 301 and an up-converter 2. That is, the receiving system 100 further includes a booster 301 and an upconverter 2.

The booster 301 amplifies the transmission signal supplied from the distributor 102 and outputs it to the upconverter 2. In at least some of the up-conversion systems 300, the booster 301 may be omitted, and the transmission signal supplied from the distributor 102 may be supplied to the up-converter 2.

The up converter 2 receives a transmission signal from the down converter 1 via the distributor 102 and the booster 301. The upconverter 2 extracts the satellite broadcast wave and the terrestrial digital broadcast wave from the transmission signal, demultiplexes the two, and outputs the two to the tuner 401. At this time, the up converter 2 up-converts the second broadcast signal of the CATV band included in the transmission signal received from the down converter 1 to the original first broadcast signal of the satellite broadcast wave of left-handed circularly polarized waves. The configuration of the upconverter 2 will be described later.

The tuner 401 selects broadcast signals of satellite broadcast waves and terrestrial digital broadcast waves input from the upconverter 2. The TV receiver 402 outputs video and audio based on the broadcast signal of the satellite broadcast wave or the terrestrial digital broadcast wave selected by the tuner 401. In at least some dwelling units, the tuner 401 and the TV receiver 402 support reception and output of 4K or 8K satellite broadcast waves, respectively. Further, in at least some dwelling units, the tuner 401 may be built in the TV receiver 402.

<1-2. Down converter ＞
Next, a configuration example of the down converter 1 will be described with reference to FIGS. 1 to 3. FIG. 3 is a block diagram showing a configuration example of the down converter 1.

As shown in FIG. 3, the down converter 1 includes a satellite broadcast input unit 111, a terrestrial broadcast input terminal 112, a DIP switch 13, a control circuit 14, a left-handed frequency conversion unit 15, a right-handed extraction unit 16, and the like. A transmission wave synthesizer 17 and an output terminal 18 are provided. The DIP switch 13, the control circuit 14, and the left-handed frequency conversion unit 15 are examples of the "first DIP switch," "first control circuit," and "first frequency conversion unit" of the present invention, respectively.

The satellite broadcast input unit 111 has a satellite broadcast input terminal (not shown) to which the satellite broadcast receiving antenna 201 is connected. The satellite broadcast input unit 111 distributes the received signal of the satellite broadcast wave output from the satellite broadcast receiving antenna 201 and outputs it to the left-handed frequency conversion unit 15 and the right-handed rotation extraction unit 16.

A terrestrial broadcast receiving antenna 202 is connected to the terrestrial broadcast input terminal 112, and a reception signal of a terrestrial digital broadcast wave output from the terrestrial broadcast receiving antenna 202 is input. The received signal of the terrestrial digital broadcast wave is output from the terrestrial broadcast input terminal 112 to the transmission wave synthesizer 17.

In the DIP switch 13, whether or not to down-convert the first broadcast signal included in the received signal of the satellite broadcast wave of left-handed circularly polarized wave to the second broadcast signal in the CATV band is set for each first broadcast signal. .. The DIP switch 13 has switches SW1 to SW25. In the following, switches SW1 to SW25 may be collectively referred to as "switch SW". The number of switches SW1 to SW25 is the sum of the number of physical channels (2ch to 24ch) of the BS left-handed broadcast wave (12) and the number of physical channels (1ch to 25ch) of the CS left-handed broadcast wave (13). It is the same. The physical channel of the first broadcast signal set to be down-converted by the DIP switch 13 is an example of the "first transmission frequency band" of the present invention.

The switches SW1 to SW12 correspond to each physical channel (2ch to 24ch) of the BS left-handed broadcast wave, and it is possible to set whether or not to down-convert the first broadcast signal of the BS left-handed broadcast wave of the corresponding physical channel. For example, when the switch SW1 is set to the ON side, it is set to down-convert the 2ch first broadcast signal of the BS left-handed broadcast wave to the second broadcast signal of the CATV band. On the other hand, when the switch SW1 is set to the OFF side, it is set that the first broadcast signal of 2ch of the BS left-handed broadcast wave is not down-converted to the second broadcast signal of the CATV band. In the latter case, the 2ch first broadcast signal of the BS left-handed broadcast wave is not transmitted because it is not included in the transmission signal output by the down converter 1. Since the relationship between ON / OFF of the switches SW2 to SW12 and whether or not to down-convert the first broadcast signal of the corresponding physical channel of the BS left-handed broadcast wave is the same as that of the switch SW1. The explanation is omitted.

The switches SW13 to SW25 correspond to each physical channel (1ch to 25ch) of the CS left-handed broadcast wave, and it is possible to set whether or not to down-convert the first broadcast signal of the CS left-handed broadcast wave of the corresponding physical channel. For example, when the switch SW13 is set to the ON side, it is set to down-convert the first broadcast signal of channel 1 of the CS left-handed broadcast wave to the second broadcast signal of the CATV band. On the other hand, when the switch SW13 is set to the OFF side, it is set that the first broadcast signal of channel 1 of the CS left-handed broadcast wave is not down-converted to the second broadcast signal of the CATV band. In the latter case, the first broadcast signal of channel 1 of the CS left-handed broadcast wave is not transmitted because it is not included in the transmission signal. Since the relationship between ON / OFF of the switches SW14 to SW25 and whether or not to down-convert the first broadcast signal of the corresponding physical channel of the CS left-handed broadcast wave is the same as that of the switch SW13, respectively. The explanation is omitted.

Here, the occupied frequency width of each physical channel of the satellite broadcast wave is 34.5 [MHz] as described above. Therefore, as shown in FIG. 2, a maximum of 12 left-handed circularly polarized satellite broadcast signals can be down-converted to the second broadcast signal in the CATV band. For example, in the low frequency range 118 to 424 [MHz] of the CATV band, the down-converted second broadcast signal can be transmitted in a maximum of eight transmission frequency bands Z1 to Z8. Further, in the high frequency band 769 to 923 [MHz] of the CATV band, the down-converted second broadcast signal can be transmitted in a maximum of four transmission frequency bands Z9 to Z12. These transmission frequency bands Z1 to Z12 are examples of the "second transmission frequency band" of the present invention.

Therefore, the number of switch SWs set on the ON side of the DIP switch 13 is preferably 12 or less. In this way, the first broadcast signals of all the physical channels corresponding to the switch SW set on the ON side can be down-converted and transmitted in the CATV band.

Further, more preferably, the number of switch SWs set on the ON side is 8 or less. In this way, the first broadcast signals of all the physical channels corresponding to the switch SW set on the ON side can be down-converted and transmitted in the low frequency range 118 to 424 [MHz] of the CATV band. Devices such as boosters 101 and 301 installed after the down converter 1 may not support signals in the CATV band other than the low frequency range 118 to 424 [MHz] depending on the model. Even if the boosters 101 and 301 are models having such specifications, the broadcast signal down-converted to the low frequency band of the CATV band can be reliably amplified by the boosters 101 and 301.

The control circuit 14 controls the left-handed frequency conversion unit 15 based on the setting of the DIP switch 13. Further, when the number of switch SWs set on the ON side by the DIP switch 13 is larger than the allowable maximum value (for example, 12), the control circuit 14 is effective in setting with the same number of switch SWs as the allowable maximum value. And invalidate other settings. For example, in this embodiment, in this case, the control circuit 14 selects and enables the same number of switch SWs as the maximum allowable value from the switch SWs set on the ON side in ascending order of the switch number. The method of selecting an effective switch SW is not limited to this example. For example, when the number of switch SWs set on the ON side is larger than the allowable maximum value, the control circuit 14 may select and enable the same number of switch SWs as the allowable maximum value in descending order of the switch numbers.

The left-handed frequency conversion unit 15 down-converts from the received signal of the satellite broadcast wave output from the satellite broadcast input unit 111 based on the control signal Sc1 output from the control circuit 14, and the left-handed circularly polarized satellite broadcast wave No. 1 Extract the broadcast signal. Further, the left-handed frequency conversion unit 15 has a CATV band in which the first broadcast signal set to be down-converted by the dip switch 13 is associated with the physical channel of the first broadcast signal in a predetermined correspondence relationship. 2 Down-convert to a broadcast signal. In principle, the above-mentioned predetermined correspondence relationship is also used in the upconverter 2.

The number of first broadcast signals of the left-handed circularly polarized satellite broadcast wave down-converted by the left-handed frequency converter 15 is smaller than the number of switches SW1 to SW25 included in the DIP switch 13. In this way, all the first broadcast signals of the left-handed circularly polarized satellite broadcast wave to be down-converted can be set by the DIP switch 13.

Further, the number of first broadcast signals down-converted by the left-handed frequency conversion unit 15 can be set to 12. In this way, all the down-converted broadcast signals of the left-handed circularly polarized satellite broadcast wave can be transmitted using the entire CATV band whose transmission frequency bands are 118 to 424 [MHz] and 769 to 923 [MHz].

Alternatively, the number of first broadcast signals down-converted by the left-handed frequency conversion unit 15 can be eight as shown in FIG. In this way, all the down-converted broadcast signals of the left-handed circularly polarized satellite broadcast wave can be transmitted using the low frequencies 118 to 424 [MHz] of the CATV band. Therefore, even if the equipment such as boosters 101 and 301 installed after the down converter 1 does not support signals in the CATV band other than the low frequency range 118 to 424 [MHz], the broadcast is down-converted to the CATV band. Processing such as amplification can be reliably performed on the signal.

The left-handed frequency conversion unit 15 synthesizes the down-converted second broadcast signal and outputs it to the transmission wave synthesis unit 17. The configuration of the left-handed frequency conversion unit 15 and an example of the down-conversion process will be described later.

The right-handed extraction unit 16 extracts the received signal of the right-handed circularly polarized satellite broadcast wave from the signal input from the satellite broadcast input unit 111, and outputs the broadcast signal to the transmission wave synthesis unit 17. For example, the right-handed extraction unit 16 has a bandpass filter for BS right-handed broadcast waves (not shown), a bandpass filter for CS right-handed broadcast waves (not shown), and a mixer (not shown). Have. The bandpass filter for the BS right-handed broadcast wave extracts the broadcast signal of the BS right-handed broadcast wave having a transmission frequency band of 1032-1489 [MHz]. The bandpass filter extracts a broadcast signal for a CS right-handed broadcast wave having a transmission frequency band of 1595 to 2071 [MHz]. The mixer synthesizes the broadcast signals output from the above two bandpass filters as the received signals of the satellite broadcast wave of right-handed circularly polarized waves.

The transmission wave synthesis unit 17 includes a second broadcast signal in the CATV band output from the left-handed frequency conversion unit 15, a reception signal of a right-handed circularly polarized satellite broadcast wave output from the right-handed extraction unit 16, and terrestrial broadcasting. A transmission signal is generated by synthesizing the reception signal of the terrestrial digital broadcast wave output from the input terminal 112, and is output to the output terminal 18.

The output terminal 18 is connected to the booster 101, and outputs a transmission signal output from the transmission wave synthesizer 17 to the booster 101.

In the above-mentioned down converter 1, the first broadcast signal of the left-handed circularly polarized satellite broadcast wave to be down-converted is set by the DIP switch 13. Further, according to a predetermined correspondence relationship, it is determined which transmission frequency band of the CATV band the first broadcast signal set to be down-converted is down-converted to the second broadcast signal. Therefore, by sharing and using predetermined correspondence information between the down converter 1 side and the up converter 2 side of the receiving system 100, the down converter 1 can be used as a physical channel of a satellite broadcast wave of left-handed circular polarization. It is not necessary to notify the upconverter 2 of which transmission frequency band of the CATV band the first broadcast signal is down-converted to the second broadcast signal. Therefore, for example, it is not necessary to newly install a cable for performing the notification in the receiving system 100. Therefore, it is possible to view the broadcast of an arbitrarily selected physical channel of the left-handed circularly polarized satellite broadcasting wave in each dwelling unit without requiring a major modification of the receiving system 100.

Further, since the first broadcast signal of the left-handed circularly polarized satellite broadcast wave is down-converted and distributed to each up-conversion system 300, the transmittable distance of the distributed signal becomes longer. Therefore, the satellite broadcast wave of left-handed circularly polarized waves can be viewed by the up-conversion system 300 without being forced to install a plurality of boosters between the distributor 102 and the up-converter 2.

<1-2-1. Left-handed frequency converter>
Next, a configuration example of the left-handed frequency conversion unit 15 of the down converter 1 will be described with reference to FIGS. 2 to 4. FIG. 4 is a block diagram showing a configuration example of the left-handed frequency conversion unit 15.

The left-handed frequency conversion unit 15 is a digital signal processing LSI (large-scale integrated circuit) in this embodiment. The left-handed frequency conversion unit 15 is a left-handed circularly polarized satellite broadcast wave set to be down-converted by the DIP switch 13 based on the control signal Sc1 output from the control circuit 14 and the predetermined correspondence relationship described above. The first broadcast signal of the above is down-converted to the second broadcast signal of the CATV band.

As shown in FIG. 4, the left-handed frequency conversion unit 15 includes an A / D converter 151, an extraction unit 152, a conversion unit 153, a synthesis unit 154, a D / A converter 155, and a determination unit 156. .. In the present embodiment, all of these components 151 to 156 are functional components of the digital signal processing LSI.

The determination unit 156 determines the physical channel of the first broadcast signal of the left-handed circularly polarized satellite broadcast wave to be down-converted based on the control signal Sc1 output from the control circuit 14. Further, the determination unit 156 determines to which transmission frequency band of the CATV band the first broadcast signal of the physical channel is down-converted based on a predetermined correspondence relationship.

The A / D converter 151 converts the analog signal input from the satellite broadcast input unit 111 into a digital transmission signal and outputs it to the extraction unit 152. The extraction unit 152 extracts the first broadcast signal of the physical channel determined by the determination unit 156 from the digital transmission signal output by the A / D converter 151, and outputs the first broadcast signal to the conversion unit 153. The conversion unit 153 down-converts the first broadcast signal extracted by the extraction unit 152 into the second broadcast signal of the transmission frequency band determined by the determination unit 156. The synthesis unit 154 synthesizes each second broadcast signal down-converted by the conversion unit 153 into a transmission signal in the CATV band, and outputs the second broadcast signal to the D / A converter 155. The D / A converter 155 converts the digital transmission signal output from the synthesizer 154 into an analog transmission signal and outputs it to the transmission wave synthesizer 17.

<1-2-2. Down conversion process>
Next, an example of the down conversion process in the down converter 1 will be described with reference to FIGS. 2 to 4.

In the present embodiment, the physical channels of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 are arranged in ascending order of frequency from the smallest physical channel in a predetermined correspondence relationship. It is associated with the transmission frequency bands Z1 to Z12 in ascending order of frequency from the smallest transmission frequency band Z1 in the CATV band. Therefore, for example, when the ON / OFF of the switches SW1 to SW25 is set as shown in FIG. 3 in the DIP switch 13, the first broadcast signals of the BS left-handed broadcast waves 8ch, 12ch, and 14ch are the transmission frequencies in the CATV band, respectively. It is associated with the second broadcast signal of the bands Z1 to Z3 in order. Further, the first broadcast signals of 9ch, 11ch, 19ch, 21ch, and 23ch of the CS left-handed broadcast wave are associated with the second broadcast signals of the transmission frequency bands Z4 to Z8 in the CATV band, respectively.

In the down-conversion process of the BS left-handed broadcast wave and the CS left-handed broadcast wave, the 8ch broadcast signal of the BS left-handed broadcast wave is frequency-converted into the transmission signal of the transmission frequency band Z1. The 8ch broadcast signal of the BS left-handed broadcast wave has the smallest transmission frequency band among the first broadcast signals of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 shown in FIG. It is a broadcast signal. The transmission frequency band Z1 is the transmission frequency band having the lowest frequency in the CATV band.

Further, the 12ch broadcast signal of the BS left-handed broadcast wave is frequency-converted into a transmission signal in the transmission frequency band Z2. The 12ch broadcast signal of the BS left-handed broadcast wave has the second transmission frequency band among the first broadcast signals of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 shown in FIG. It is a small broadcast signal. The transmission frequency band Z2 is the transmission frequency band having the second lowest frequency in the CATV band.

Further, the broadcast signal of 14ch of the BS left-handed broadcast wave is frequency-converted to the transmission signal of the transmission frequency band Z3. The 14ch broadcast signal of the BS left-handed broadcast wave has the third transmission frequency band among the first broadcast signals of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 shown in FIG. It is a small broadcast signal. The transmission frequency band Z3 is a transmission frequency band having the third lowest frequency in the CATV band.

Further, the 9ch broadcast signal of the CS left-handed broadcast wave is frequency-converted into a transmission signal in the transmission frequency band Z4. The 9ch broadcast signal of the CS left-handed broadcast wave has the fourth transmission frequency band among the first broadcast signals of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 shown in FIG. It is a small broadcast signal. The transmission frequency band Z4 is a transmission frequency band having the fourth lowest frequency in the CATV band.

Further, the 11ch broadcast signal of the CS left-handed broadcast wave is frequency-converted into a transmission signal in the transmission frequency band Z5. The 11ch broadcast signal of the CS left-handed broadcast wave has the fifth transmission frequency band among the first broadcast signals of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 shown in FIG. It is a small broadcast signal. The transmission frequency band Z5 is a transmission frequency band having the fifth lowest frequency in the CATV band.

Further, the broadcast signal of 19ch of the CS left-handed broadcast wave is frequency-converted to the transmission signal of the transmission frequency band Z6. The 19ch broadcast signal of the CS left-handed broadcast wave has the sixth transmission frequency band among the first broadcast signals of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 shown in FIG. It is a small broadcast signal. The transmission frequency band Z6 is a transmission frequency band having the sixth lowest frequency in the CATV band.

Further, the 21ch broadcast signal of the CS left-handed broadcast wave is frequency-converted into a transmission signal in the transmission frequency band Z7. The 21ch broadcast signal of the CS left-handed broadcast wave has the seventh transmission frequency band among the first broadcast signals of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 shown in FIG. It is a small broadcast signal. The transmission frequency band Z7 is a transmission frequency band having the seventh lowest frequency in the CATV band.

Further, the broadcast signal of 23ch of the CS left-handed broadcast wave is frequency-converted to the transmission signal of the transmission frequency band Z8. The 23ch broadcast signal of the CS left-handed broadcast wave has the eighth transmission frequency band among the first broadcast signals of the left-handed circularly polarized satellite broadcast wave set to be down-converted by the dip switch 13 shown in FIG. It is a small broadcast signal. The transmission frequency band Z8 is a transmission frequency band having the eighth lowest frequency in the CATV band.

The second broadcast signal in the CATV band down-converted to the transmission frequency bands Z1 to Z8 is synthesized as a transmission signal together with the broadcast signal of the right-handed circularly polarized satellite broadcast wave and the broadcast signal of the terrestrial digital broadcast wave.

<1-3. Upconverter>
Next, a configuration example of the upconverter 2 will be described with reference to FIGS. 1 to 2 and 5. FIG. 5 is a block diagram showing a configuration example of the upconverter 2.

As shown in FIG. 5, the upconverter 2 includes an input terminal 21, a demultiplexer 22, a DIP switch 23, a control circuit 24, a CATV frequency conversion unit 25, a BS / CS synthesis unit 27, and satellite broadcasting. It has an output terminal 281 and a terrestrial broadcasting output terminal 282. The DIP switch 23, the control circuit 24, and the CATV frequency conversion unit 25 are examples of the "second DIP switch", "second control circuit", and "second frequency conversion unit" of the present invention, respectively.

The input terminal 21 is connected to the booster 301. The transmission signal output from the down converter 1 and distributed by the distributor 102 is input to the input terminal 21 via the booster 301. The transmission signal is output to the demultiplexer 22.

The demultiplexer 22 converts the transmission signal input from the input terminal 21 into a second broadcast signal in the CATV band, a reception signal of a right-handed circularly polarized satellite broadcast wave, and a reception signal of a terrestrial digital broadcast wave. Demultiplex. The second broadcast signal in the CATV band is output to the CATV frequency conversion unit 25. The reception signal of the satellite broadcast wave of right-handed circularly polarized waves is output to the BS / CS synthesis unit 27. The broadcast signal of the terrestrial digital broadcast wave is output to the terrestrial broadcast output terminal 282.

The DIP switch 23 sets the first broadcast signal of the left-handed circularly polarized satellite broadcast wave that is up-converted from the second broadcast signal in the CATV band. The DIP switch 23 has switches SWa1 to SWa25. In the following, the switches SW1a to SWa25 may be collectively referred to as "switch SWa". The number of switches SWa1 to SWa25 is 25, which is the same as the total number of physical channels of the BS left-handed broadcast wave and the CS left-handed broadcast wave, and is the same as the number of switches SW1 to SW25 included in the DIP switch 13 of the down converter 1.

The switches SWa1 to SWa12 correspond to each physical channel (2ch to 24ch) of the BS left-handed broadcast wave, and determine whether or not to up-convert the second broadcast signal of the CATV band to the first broadcast signal of the corresponding physical channel. Can be set. For example, when the switch SWa1 is set to the ON side, it is set to up-convert the second broadcast signal in the CATV band to 2ch of the BS left-handed broadcast wave. On the other hand, when the switch SWa1 is set to the OFF side, it is set not to be up-converted to 2ch of the BS left-handed broadcast wave. Since the relationship between ON / OFF of the switches SWa2 to SWa12 and whether or not to up-convert to the first broadcast signal of the corresponding physical channel of the BS left-handed broadcast wave is the same as that of the switch SWa1. The explanation is omitted.

The switches SWa13 to SWa25 correspond to each physical channel (1ch to 25ch) of the CS left-handed broadcast wave, and determine whether or not to up-convert the second broadcast signal of the CATV band to the first broadcast signal of the corresponding physical channel. Can be set. For example, when the switch SWa13 is set to the ON side, it is set to up-convert the second broadcast signal in the CATV band to 13ch of the CS left-handed broadcast wave. On the other hand, when the switch SWa13 is set to the OFF side, it is set not to be up-converted to 13ch of the CS left-handed broadcast wave. Since the relationship between ON / OFF of the switches SWa14 to SWa25 and whether or not to up-convert to the first broadcast signal of the corresponding physical channel of the CS left-handed broadcast wave is the same as that of the switch SWa13, respectively. The explanation is omitted.

The ON / OFF setting of the switches SWa1 to SWa25 is basically the same as the ON / OFF setting of the switches SW1 to SW25 of the DIP switch 13 in the down converter 1. Further, the number of switch SWs set on the ON side of the DIP switch 13 is preferably 12 or less, and more preferably 8 or less.

The control circuit 24 controls the CATV frequency conversion unit 25 based on the setting of the DIP switch 23. Further, when the number of switches SWa set to ON by the DIP switch 23 is larger than the allowable maximum value (for example, 12), the control circuit 24 has the same number of switches as the allowable maximum value among the switches SWa1 to SWa25. Enable the settings in SWa and disable other settings. The method of selecting the switch SWa, which is effective in this case, is the same as the method of selecting the switch SW in the control circuit 14.

The CATV frequency conversion unit 25 extracts the second broadcast signal of the CATV band from the output signal of the demultiplexer 22. Further, the physical channel of the first broadcast signal of the left-handed circularly polarized satellite broadcast wave set to be up-converted by the DIP switch 23 is associated with the transmission frequency band of the CATV band in a predetermined correspondence relationship. Has been done. The CATV frequency conversion unit 25 up-converts the second broadcast signal in the CATV band to the first broadcast signal of the left-handed circularly polarized satellite broadcast wave based on the control signal Sc2 output from the control circuit 24 and the corresponding relationship. .. The predetermined correspondence used in the up converter 2 is, in principle, the same as that used in the down converter 1. Further, the CATV frequency conversion unit 25 synthesizes the up-converted first broadcast signal and outputs it to the BS / CS synthesis unit 27. The configuration of the CATV frequency conversion unit 25 and examples of the up-conversion process will be described later.

The BS / CS synthesis unit 27 is a first broadcast signal of a left-handed circularly polarized satellite broadcast wave output from the CATV frequency converter 25 and a right-handed circularly polarized satellite broadcast wave output from the demultiplexer 22. A satellite broadcast signal synthesized with the received signal is generated and output to the satellite broadcast output terminal 281.

The satellite broadcast output terminal 281 and the terrestrial broadcast output terminal 282 are connected to the tuner 401. The satellite broadcasting output terminal 281 outputs the satellite broadcasting signal input from the BS / CS synthesis unit 27 to the tuner 401. The terrestrial broadcast output terminal 282 outputs a reception signal of the terrestrial digital broadcast wave input from the demultiplexer 22 to the tuner 401.

According to the above-mentioned upconverter 2, the dip switch 23 sets which physical channel of the left-handed circularly polarized satellite broadcast wave the second broadcast signal in the CATV band is up-converted to the first broadcast signal. Further, a predetermined correspondence relationship determines which physical channel of the satellite broadcast wave of the left-handed circularly polarized wave to up-convert the second broadcast signal of which transmission frequency band of the CATV band. Therefore, by sharing and using predetermined correspondence information between the down converter 1 side and the up converter 2 side of the receiving system 100, the up converter 2 can use the second broadcast signal of which transmission frequency band of the CATV band. It is not necessary to receive a notification from the down converter 1 as to which physical channel of the satellite broadcast wave of the left-handed circularly polarized wave is up-converted to the first broadcast signal. Therefore, for example, since it is not necessary to newly install a cable for performing the notification in the receiving system 100, the satellite broadcasting wave of left-handed circularly polarized waves can be arbitrarily installed in each dwelling unit without requiring a major modification of the receiving system 100. You can make the broadcast of the selected physical channel available for viewing.

<1-3-1. CATV frequency converter>
Next, a configuration example of the CATV frequency conversion unit 25 of the upconverter 2 will be described with reference to FIGS. 2 and 5 to 6. FIG. 6 is a block diagram showing a configuration example of the CATV frequency conversion unit 25.

The CATV frequency conversion unit 25 is a digital signal processing LSI in this embodiment. The physical channel of the first broadcast signal of the left-handed circularly polarized satellite broadcast wave set to be up-converted by the dip switch 23 has a transmission frequency of the second broadcast signal in the CATV band due to a predetermined correspondence. It is associated with the bands Z1 to Z12. The CATV frequency conversion unit 25 uses the CATV as the first broadcast signal of the left-handed circularly polarized satellite broadcast wave set to be up-converted based on the correspondence and the control signal Sc2 output from the control circuit 24. Up-convert the second broadcast signal of the band.

As shown in FIG. 6, the CATV frequency conversion unit 25 includes an A / D converter 251, an extraction unit 252, a conversion unit 253, a synthesis unit 254, a D / A converter 255, and a determination unit 256. .. In the present embodiment, all of these components 251 to 256 are functional components of the digital signal processing LSI.

Based on the control signal Sc2 output from the control circuit 24 and the predetermined correspondence relationship described above, the determination unit 256 sets the second broadcast signal of which transmission frequency band of the CATV band to the left-handed circularly polarized satellite broadcast wave. It is determined which physical channel of the throat is up-converted to the first broadcast signal.

The A / D converter 251 converts the analog signal input from the demultiplexer 22 into a digital transmission signal and outputs it to the extraction unit 252. The extraction unit 252 extracts the second broadcast signal of each transmission frequency band Z1 to Z12 of the CATV band from the digital transmission signal output by the A / D converter 251 and outputs the second broadcast signal to the conversion unit 253. The conversion unit 253 up-converts the second broadcast signal extracted by the extraction unit 252 to the first broadcast signal of the physical channel determined by the determination unit 256, respectively. The synthesis unit 254 synthesizes each first broadcast signal up-converted by the conversion unit 253 into a transmission signal of a satellite broadcast wave of left-handed circularly polarized waves, and outputs the signal to the D / A converter 255. The D / A converter 255 converts the digital transmission signal output from the synthesis unit 254 into an analog transmission signal and outputs it to the BS / CS synthesis unit 27.

<1-3-2. Up-conversion processing>
Next, an example of the up-conversion process in the up-converter 2 will be described with reference to FIGS. 2 and 5 to 6.

In the present embodiment, the transmission frequency bands Z1 to Z12 in ascending order of frequency from the minimum transmission frequency band Z1 in the CATV band are up-converted by the dip switch 23, respectively, in a predetermined correspondence relationship. The physical channel of the first broadcast signal of the left-handed circularly polarized satellite broadcast wave set as and the smallest physical channel are associated with each other in ascending order of frequency. Therefore, for example, when the ON / OFF of the switches SWa1 to SWa25 is set as shown in FIG. 6 in the DIP switch 23, the second broadcast signals of the transmission frequency bands Z1 to Z3 in the CATV band are 8 channels of the BS left-handed broadcast wave, respectively. , 12ch, 14ch are associated with the first broadcast signal in order. Further, the second broadcast signals of the transmission frequency bands Z4 to Z8 in the CATV band are associated with the first broadcast signals of 9ch, 11ch, 19ch, 21ch, and 23ch of the CS left-handed broadcast wave, respectively.

In the up-conversion process of the BS left-handed broadcast wave and the CS left-handed broadcast wave, the transmission signal of the transmission frequency band Z1 of the CATV band is frequency-converted into the 8ch broadcast signal of the BS left-handed broadcast wave. The 8ch broadcast signal of the BS left-handed broadcast wave has a transmission frequency band of the first broadcast signal of the left-handed circularly polarized satellite broadcast wave set to be up-converted by the dip switch 23 shown in FIG. It is the smallest broadcast signal.

Further, the transmission signal of the transmission frequency band Z2 of the CATV band is frequency-converted into a 12ch broadcast signal of the BS left-handed broadcast wave. The 12ch broadcast signal of the BS left-handed broadcast wave has the second transmission frequency band among the left-handed circularly polarized satellite broadcast signals set to be up-converted by the dip switch 23 shown in FIG. It is a small broadcast signal.

Further, the transmission signal of the transmission frequency band Z3 of the CATV band is frequency-converted to the 14ch broadcast signal of the BS left-handed broadcast wave. The 14ch broadcast signal of the BS left-handed broadcast wave has the third transmission frequency band among the left-handed circularly polarized satellite broadcast signals set to be up-converted by the dip switch 23 shown in FIG. It is a small broadcast signal.

Further, the transmission signal of the transmission frequency band Z4 of the CATV band is frequency-converted into a 9ch broadcast signal of the CS left-handed broadcast wave. The 9ch broadcast signal of the CS left-handed broadcast wave has the fourth transmission frequency band among the left-handed circularly polarized satellite broadcast signals set to be up-converted by the dip switch 23 shown in FIG. It is a small broadcast signal.

Further, the transmission signal of the transmission frequency band Z5 of the CATV band is frequency-converted to the 11ch broadcast signal of the CS left-handed broadcast wave. The 11ch broadcast signal of the CS left-handed broadcast wave has the fifth transmission frequency band among the left-handed circularly polarized satellite broadcast signals set to be up-converted by the dip switch 23 shown in FIG. It is a small broadcast signal.

Further, the transmission signal of the transmission frequency band Z6 of the CATV band is frequency-converted to the 19ch broadcast signal of the CS left-handed broadcast wave. The 19ch broadcast signal of the CS left-handed broadcast wave has the sixth transmission frequency band among the left-handed circularly polarized satellite broadcast signals set to be up-converted by the dip switch 23 shown in FIG. It is a small broadcast signal.

Further, the transmission signal of the transmission frequency band Z7 of the CATV band is frequency-converted to the 21ch broadcast signal of the CS left-handed broadcast wave. The 21ch broadcast signal of the CS left-handed broadcast wave has the seventh transmission frequency band among the left-handed circularly polarized satellite broadcast signals set to be up-converted by the dip switch 23 shown in FIG. It is a small broadcast signal.

Further, the transmission signal of the transmission frequency band Z6 of the CATV band is frequency-converted to the broadcast signal of 23ch of the CS left-handed broadcast wave. The 23ch broadcast signal of the CS left-handed broadcast wave has the eighth transmission frequency band among the left-handed circularly polarized satellite broadcast signals set to be up-converted by the dip switch 23 shown in FIG. It is a small broadcast signal.

The first broadcast signal of the up-converted left-handed circularly polarized satellite broadcast waves (that is, BS left-handed broadcast waves 8ch, 12ch, 14ch, and CS left-handed broadcast waves 9ch, 11ch, 19ch, 21ch, 23ch) is on the right. It is combined as a satellite broadcast signal together with the received signal of the circularly polarized satellite broadcast wave.

<2. Modification example>
Next, the correspondence between the physical channels of the left-handed circularly polarized satellite broadcasting waves in the down converter 1 and the up converter 2 and the transmission frequency bands Z1 to Z12 of the CATV band is not limited to the above-described embodiment. In the following modification, a configuration different from the embodiment will be described. Further, the same components as those in the embodiment are designated by the same reference numerals, and the description thereof may be omitted.

<2-1. First modification>
For example, the physical channels of the first broadcast signal of the left-handed circularly polarized satellite broadcast wave set to be down-converted (up-converted) by the dip switch 13 (dip switch 23) are in ascending order of frequency from the smallest physical channel. It may be associated with the transmission frequency bands Z12 to Z1 in descending order of frequency from the maximum transmission frequency band Z12 in the CATV band. FIG. 7 is a diagram for explaining a first modification of the transmission of satellite broadcast waves in the receiving system 100. In FIG. 7, the physical channel of the CS right-handed broadcast wave is not shown.

In the first modification, when the DIP switches 13 and 23 are set as shown in FIGS. 3 and 5, 8ch, 12ch, and 14ch of the BS left-handed broadcast wave correspond to the transmission frequency bands Z12 to Z10 of the CATV band, respectively. Attached. Further, 9ch, 11ch, 19ch, 21ch, and 23ch of the CS left-handed broadcast wave are associated with the transmission frequency bands Z9 to Z5 of the CATV band, respectively.

Therefore, in the down-conversion processing of the BS left-handed broadcast wave and the CS left-handed broadcast wave, the first broadcast signal of the BS left-handed broadcast wave 8ch, 12ch, 14ch and the first of the CS left-handed broadcast wave 9ch, 11ch, 19ch, 21ch, 23ch. The broadcast signal is frequency-converted into the second broadcast signal of the transmission frequency bands Z12, Z11, Z10, Z9, Z8, Z7, Z6, and Z5 of the CATV band in this order. The second broadcast signal of the CATV band down-converted to the transmission frequency bands Z12 to Z5 is synthesized as a transmission signal together with the broadcast signal of the satellite broadcast wave of right-handed circular polarization and the broadcast signal of the terrestrial digital broadcast wave. .. The transmission signal is distributed by the distributor 102 and transmitted to each up-conversion system 300.

Further, in the up-conversion processing of the BS left-handed broadcast wave and the CS left-handed broadcast wave, the second broadcast signals of the transmission frequency bands Z12, Z11, Z10, Z9, Z8, Z7, Z6, and Z5 of the CATV band are BS left-handed broadcast in this order. The frequencies are converted into the first broadcast signals of 8ch, 12ch, and 14ch of the wave and the first broadcast signals of 9ch, 11ch, 19ch, 21ch, and 23ch of the CS left-handed broadcast wave, respectively. The first broadcast signal of the up-converted left-handed circularly polarized satellite broadcast waves (that is, BS left-handed broadcast waves 8ch, 12ch, 14ch, and CS left-handed broadcast waves 9ch, 11ch, 19ch, 21ch, 23ch) is on the right. It is combined as a satellite broadcast signal together with the received signal of the circularly polarized satellite broadcast wave.

<2-2. Second modification>
Alternatively, the physical channels of the first broadcast signal of the left-handed circularly polarized satellite broadcast wave set to be down-converted (up-converted) by the dip switch 13 (dip switch 23) are in ascending order of frequency from the smallest physical channel. In the CATV band, it may be associated with the transmission frequency bands Z8 to Z1 in descending order from the maximum transmission frequency band Z8 among the low frequencies 118 to 424 [MHz] having a frequency smaller than that of the terrestrial digital broadcast wave. FIG. 8 is a diagram for explaining a second modification of the transmission of satellite broadcast waves in the receiving system 100. In FIG. 8, the physical channel of the CS right-handed broadcast wave is not shown.

In the second modification, when the DIP switches 13 and 23 are set as shown in FIGS. 3 and 5, 8ch, 12ch, and 14ch of the BS left-handed broadcast wave correspond to the transmission frequency bands Z8 to Z6 of the CATV band, respectively. Attached. Further, 9ch, 11ch, 19ch, 21ch, and 23ch of the CS left-handed broadcast wave are associated with the transmission frequency bands Z5 to Z1 of the CATV band, respectively.

Therefore, in the down-conversion processing of the BS left-handed broadcast wave and the CS left-handed broadcast wave, the first broadcast signal of the BS left-handed broadcast wave 8ch, 12ch, 14ch and the first of the CS left-handed broadcast wave 9ch, 11ch, 19ch, 21ch, 23ch. The broadcast signal is frequency-converted into the second broadcast signal of the transmission frequency bands Z8, Z7, Z6, Z5, Z4, Z3, Z2, and Z1 of the CATV band in this order. The second broadcast signal in the CATV band down-converted to the transmission frequency bands Z8 to Z1 is synthesized as a transmission signal together with the broadcast signal of the right-handed circularly polarized satellite broadcast wave and the broadcast signal of the terrestrial digital broadcast wave. The transmission signal is distributed by the distributor 102 and transmitted to each up-conversion system 300.

Further, in the up-conversion processing of the BS left-handed broadcast wave and the CS left-handed broadcast wave, the second broadcast signals of the transmission frequency bands Z8, Z7, Z6, Z5, Z4, Z3, Z2, and Z1 of the CATV band are BS left-handed broadcast in this order. The frequencies are converted into the first broadcast signals of 8ch, 12ch, and 14ch of the wave and the first broadcast signals of 9ch, 11ch, 19ch, 21ch, and 23ch of the CS left-handed broadcast wave, respectively. The first broadcast signal of the up-converted left-handed circularly polarized satellite broadcast waves (that is, BS left-handed broadcast waves 8ch, 12ch, 14ch, and CS left-handed broadcast waves 9ch, 11ch, 19ch, 21ch, 23ch) is on the right. It is combined as a satellite broadcast signal together with the received signal of the circularly polarized satellite broadcast wave.

<2-3. Other variants>
For example, in the above-described first and second modifications, the left-handed frequency conversion unit 15 and the CATV frequency conversion unit 25 are digital signal processing LSIs, and the A / D converter 151,251, extraction units 152,252, and conversion. Units 153, 253, synthesis unit 154, 254, D / A converter 155, 255, and determination unit 156, 256 were all functional components of the digital signal processing LSI. However, the present invention is not limited to these examples, and the A / D converter 151,251, the extraction unit 152,252, the conversion unit 153,253, the synthesis unit 154,254, the D / A converter 155,255, and the determination unit 156,256. Part or all of the above may be realized by physical components such as electric circuits, elements, and devices.

Further, in the above-described first and second modifications, the left-handed frequency conversion unit 15 and the CATV frequency conversion unit 25 are both components that perform digital processing. However, the present invention is not limited to this example, and one or both of the left-handed frequency conversion unit 15 and the CATV frequency conversion unit 25 may be components that perform analog processing. When the left-handed frequency conversion unit 15 is a component that performs analog processing, the A / D converter 151 and the D / A converter 155 can be omitted. Further, when the CATV frequency conversion unit 25 is a component that performs analog processing, the A / D converter 251 and the D / A converter 255 can be omitted.

<4. Summary>
In the down converter 1 described above, whether or not to downconvert the first broadcast signal included in the received signal of the satellite broadcast wave of left-handed circular polarization to the second broadcast signal in the CATV band is set for each first broadcast signal. The dip switch 13 is controlled, the left-handed frequency conversion unit 15 that extracts the first broadcast signal from the received signal and down-converts it into the second broadcast signal, and the left-handed frequency conversion unit 15 based on the settings of the dip switch 13. The left-handed frequency conversion unit 15 including the control circuit 14 predetermines the first broadcast signal set to be down-converted by the dip switch 13 as the physical channel (first transmission frequency band) of the first broadcast signal. It is configured to be down-converted to the second broadcast signal of the second transmission frequency band associated with the corresponding correspondence (first configuration).

According to the first configuration, the first broadcast signal of the left-handed circularly polarized satellite broadcast wave to be down-converted is set by the DIP switch 13. Further, according to a predetermined correspondence relationship, it is determined which transmission frequency band of the CATV band the first broadcast signal set to be down-converted is down-converted to the second broadcast signal. Therefore, by sharing and using predetermined correspondence information between the down converter 1 side and the up converter 2 side of the receiving system 100, the down converter 1 can be used as a physical channel of a satellite broadcast wave of left-handed circular polarization. It is not necessary to notify the upconverter 2 of which transmission frequency band of the CATV band the first broadcast signal is to be down-converted. Therefore, for example, it is not necessary to newly install a cable for performing the notification in the receiving system 100. Therefore, it is possible to view the broadcast of an arbitrarily selected physical channel of the left-handed circularly polarized satellite broadcasting wave in each dwelling unit without requiring a major modification of the receiving system 100.

Further, since the first broadcast signal of the left-handed circularly polarized satellite broadcast wave is down-converted and distributed to each up-conversion system 300, the transmittable distance of the distributed signal becomes longer. Therefore, the satellite broadcast wave of left-handed circularly polarized waves can be viewed by the up-conversion system 300 without being forced to install a plurality of boosters between the distributor 102 and the up-converter 2.

In the down converter 1 having the first configuration, the satellite broadcast wave may have a configuration (second configuration) including a left-handed circularly polarized BS broadcast wave and a left-handed circularly polarized CS broadcast wave. ..

According to the second configuration, the BS left-handed broadcast wave and the CS left-handed broadcast wave can be viewed in each of the up-conversion systems 300.

In the down converter 1 having the first or second configuration, the physical channels (first transmission frequency bands) of the first broadcast signal set to be down-converted by the dip switch 13 are in ascending order of frequency from the smallest physical channel. , The configuration may be associated with the second transmission frequency band in ascending order from the smallest second transmission frequency band (third configuration).

According to the third configuration, the predetermined correspondence relationship can be easily set. In addition, devices such as booster 301 installed after the down converter 1 support low frequencies 118 to 424 [MHz] in the CATV band depending on the model, but high frequencies 769 to 923 [ It may not correspond to the CATV band of [MHz]. Due to the above-mentioned predetermined correspondence, the first broadcast signal can be preferentially down-converted to the low frequency range 118 to 424 [MHz] in the CATV band, so that, for example, the booster 301 between the distributor 102 and the upconverter 2 can be used. Even with the model having the above specifications, the booster 301 can reliably amplify the broadcast number down-converted to the CATV band.

In the down converter 1 having any of the first to third configurations, the DIP switch 13 has the number of first broadcast signals of the left-handed circularly polarized satellite broadcast wave down-converted by the left-handed frequency converter 15. The configuration may be smaller than the number of switches SW1 to SW25 (fourth configuration).

According to the fourth configuration, all the first broadcast signals of the left-handed circularly polarized satellite broadcast wave to be down-converted can be set by the DIP switch 13.

In the down converter 1 having the fourth configuration, the number may be 12 or 8 (fifth configuration).

According to the fifth configuration, by setting the number of first broadcast signals to be down-converted to 12, the entire CATV band in which the transmission frequency band is 118 to 424 [MHz] and 769 to 923 [MHz] is covered. It can be used to transmit all down-converted broadcast signals of left-handed circularly polarized satellite broadcast waves.

Alternatively, by setting the number of first broadcast signals to be down-converted to eight, a down-converted broadcast signal of a left-handed circularly polarized satellite broadcast wave is used using the low frequency range 118 to 424 [MHz] of the CATV band. Can all be transmitted. Therefore, even if the equipment such as boosters 101 and 301 installed after the down converter 1 does not support signals in the CATV band other than the low frequency range 118 to 424 [MHz], the broadcast is down-converted to the CATV band. Processing such as amplification can be reliably performed on the signal.

Further, the up-converter 2 described above uses a left-handed circularly polarized satellite broadcast wave for the second broadcast signal in the CATV band included in the transmission signal received from the down converter 1 having any of the first to fifth configurations. A dip switch 23 that up-converts to the first broadcast signal of the above, and sets the first broadcast signal to be up-converted from the second broadcast signal, and up-converts the second broadcast issue to the first broadcast signal. The first broadcast, which includes a CATV frequency conversion unit 25 for the operation and a control circuit 24 for controlling the CATV frequency conversion unit 25 based on the setting of the dip switch 23, and is set to be up-converted by the dip switch 23. The physical channel (first transmission frequency band) of the signal is associated with the second transmission frequency band of the second broadcast signal in a predetermined correspondence relationship, and the CATV frequency conversion unit 25 is based on the correspondence relationship with the second transmission frequency band. The configuration is such that the broadcast signal is up-converted to the first broadcast signal (sixth configuration).

According to the sixth configuration, the DIP switch 23 sets to which physical channel of the first broadcast signal the second broadcast signal in the CATV band is up-converted. Further, a predetermined correspondence relationship determines which physical channel of the reception signal of the satellite broadcast wave of left-handed circularly polarized wave to up-convert the second broadcast signal of which transmission frequency band of the CATV band. Therefore, by sharing and using predetermined correspondence information between the down converter 1 side and the up converter 2 side of the receiving system 100, the up converter 2 can use the second broadcast signal of which transmission frequency band of the CATV band. It is not necessary to receive a notification from the down converter 1 as to which physical channel of the satellite broadcast wave of the left-handed circularly polarized wave is up-converted to the first broadcast signal. Therefore, for example, it is not necessary to newly install a cable for performing the notification in the receiving system 100. Therefore, it is possible to view the broadcast of an arbitrarily selected physical channel of the satellite broadcast wave of left-handed circularly polarized wave without requiring a major modification of the receiving system 100.

Further, the receiving system 100 described above includes a down converter 1 having any one of the first to fifth configurations and an up converter 2 having the sixth configuration (seventh configuration). It is said that.

According to the seventh configuration, it is possible to view the broadcast of an arbitrarily selected physical channel of the satellite broadcast wave of left-handed circularly polarized wave without requiring a major modification of the receiving system.

The embodiment of the present invention has been described above. It should be noted that the above-described embodiment is an example, and various modifications can be made to the combination of each component and each process, and it is understood by those skilled in the art that it is within the scope of the present invention.

100 Reception system 101 Booster 102 Distributor 201 Satellite broadcast reception antenna 202 Terrestrial broadcast reception antenna 300 Up-conversion system 301 Booster 401 Tuner 402 TV receiver 1 Down converter 111 Satellite broadcast input unit 112 Terrestrial broadcast input terminal 13 Dip switch 14 Control circuit 15 Left-handed frequency converter 151 A / D converter 152 Extractor 153 Converter 154 Synthesizer 155 D / A converter 156 Determiner 16 Right-handed extractor 17 Transmission wave synthesizer 18 Output terminal 2 Upconverter 21 Input terminal 22 Demultiplexer 23 Dip switch 24 Control circuit 25 CATV frequency conversion unit 251 A / D converter 252 Extraction unit 253 Conversion unit 254 Synthesis unit 255 D / A converter 256 Determination unit 27 BS / CS synthesis unit 281 Satellite broadcast output terminal 282 Terrestrial broadcast output terminal SW, SW1 to SW25, SWa, SWa1 to SWa25 Switch Z1 to Z12 Transmission frequency band

Claims (7)

A first dip switch in which whether or not to down-convert the first broadcast signal included in the received signal of the left-handed circularly polarized satellite broadcast wave to the second broadcast signal in the CATV band is set for each first broadcast signal.
A first frequency conversion unit that extracts the first broadcast signal from the received signal and down-converts it into the second broadcast signal.
A first control circuit that controls the first frequency conversion unit based on the setting of the first DIP switch, and
With
The first frequency conversion unit associates the first broadcast signal set to be down-converted by the first dip switch with the first transmission frequency band of the first broadcast signal in a predetermined correspondence relationship. A down converter that down-converts to the second broadcast signal in the second transmission frequency band. The down converter according to claim 1, wherein the satellite broadcast wave includes a left-handed circularly polarized BS broadcast wave and a left-handed circularly polarized CS broadcast wave. The first transmission frequency band of the first broadcast signal set to be down-converted by the first dip switch is from the smallest second transmission frequency band in ascending order of frequency from the smallest first transmission frequency band. The down converter according to claim 1 or 2, which is associated with the second transmission frequency band in ascending order of frequency. The down converter according to any one of claims 1 to 3, wherein the number of the first broadcast signals down-converted by the first frequency conversion unit is smaller than the number of switches included in the first DIP switch. The down converter according to claim 4, wherein the number is 12 or 8. A transmission signal is received from the down converter according to any one of claims 1 to 5, and the second broadcast signal in the CATV band included in the transmission signal is broadcast as the first broadcast of a left-handed circularly polarized satellite broadcast wave. An upconverter that upconverts to a signal
A second DIP switch on which the first broadcast signal up-converted from the second broadcast signal is set, and
A second frequency converter that up-converts the second broadcast signal to the first broadcast signal, and
A second control circuit that controls the second frequency converter based on the settings made by the second DIP switch, and
With
The first transmission frequency band of the first broadcast signal set to be up-converted by the second DIP switch is associated with the second transmission frequency band of the second broadcast signal in a predetermined correspondence relationship. Be,
The second frequency conversion unit is an upconverter that up-converts the second broadcast signal to the first broadcast signal based on the correspondence. The down converter according to any one of claims 1 to 5.
The upconverter according to claim 6 and
A receiving system.

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