EP1734680A2

EP1734680A2 - Frequency converter for satellite broadcast reception

Info

Publication number: EP1734680A2
Application number: EP06113312A
Authority: EP
Inventors: Keiichiro Sato
Original assignee: Alps Electric Co Ltd
Current assignee: Alps Alpine Co Ltd
Priority date: 2005-06-14
Filing date: 2006-04-28
Publication date: 2006-12-20
Also published as: JP2006352348A

Abstract

A frequency converter for satellite broadcasting reception includes: a first frequency-converting unit which converts the frequencies of horizontally-polarized signals of a plurality of channels and vertically-polarized signals of a plurality of channels to generate horizontally-polarized intermediate-frequency signals of a plurality of channels and vertically-polarized intermediate-frequency signals of a plurality of channels; signal selecting units each selecting a horizontally-polarized or vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels obtained by the first frequency-converting unit; and a second frequency-converting unit which converts the intermediate-frequency signal of the one channel obtained by the signal selecting unit into a first or second intermediate-frequency signal of another channel having a different frequency from that of the intermediate-frequency signal of the one channel. The first or second intermediate-frequency signal of anther channel obtained by the second frequency-converting unit is supplied to a conventional broadcasting signal receiver.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a frequency converter for satellite broadcasting reception, and more particularly, to a frequency converter having a simple structure, a small number of components, and a small size.

2. Description of the Related Art

In general, in order for a conventional broadcasting signal receiver to receive satellite broadcasting signals, it is required to connect a frequency converter for satellite broadcasting reception between the conventional broadcasting signal receiver and a satellite broadcasting signal receiving antenna. In this case, the frequency converter for satellite broadcasting reception receives a satellite broadcasting wave transmitted from a satellite, converts of the frequency of the received broadcasting signal into a broadcasting signal in a general frequency band, and supplies the converted signal to the conventional broadcasting signal receiver.
FIG. 3 is a block diagram showing the configuration of an example of a well-known frequency converter for satellite broadcasting reception which is disclosed in JP-A-2003-152588 .
As shown in FIG. 3, the frequency converter for satellite broadcasting reception includes: a horizontally-polarized-signal amplifier 51; a vertically-polarized-signal amplifier 52; a first signal splitter 53; a second signal splitter 54; a first band pass filter group 55; a second band pass filter group 56; a first frequency-converting unit 57; a second frequency-converting unit 58; a first intermediate-frequency signal amplifier group 59; a second intermediate-frequency signal amplifier group 60; a first signal splitter group 61; a second signal splitter group 62; a 4 x 2 selector switch circuit 63; a 4 x 1 selector switch circuit 64; a third frequency-converting unit 65; a fourth frequency-converting unit 66; a third band pass filter group 67; a signal synthesizer 68; a first output amplifier 69; a second output amplifier 70; a first signal input terminal 71; a second signal input terminal 72; a first signal output terminal 73; and a second signal output terminal 74.
In this case, the horizontally-polarized-signal amplifier 51 has two cascaded amplifiers 51a and 51b, and the vertically-polarized signal amplifier 52 has two cascaded amplifiers 52a and 52b. The first band pass filter group 55 has two band pass filters 55a and 55b disposed in parallel to each other, and the second band pass filter group 56 has two band pass filters 56a and 56b disposed in parallel to each other. The first frequency-converting unit 57 has two frequency mixing stages 57a and 57b and one local oscillator 57c, and the second frequency converting unit 58 has two frequency mixing stages 58a and 58b and one local oscillator 58c. The first intermediate-frequency signal amplifier group 59 has two amplifiers 59a and 59b disposed in parallel to each other, and the second intermediate-frequency signal amplifier group 60 has two amplifiers 60a and 60b disposed in parallel to each other. The first signal splitter group 61 has two signal splitters 61a and 61b disposed in parallel to each other, and the second signal splitter group 62 has two signal splitters 62a and 62b disposed in parallel to each other. The third frequency-converting unit 65 has a frequency mixing stage 65a and a local oscillator 65b, and the fourth frequency-converting unit 66 has a frequency mixing stage 66a and a local oscillator 66b. The third band pass filter group 67 has two band pass filters 67a and 67b disposed in parallel to each other. The second output amplifier 70 has two cascaded amplifiers 70a and 70b.
In the frequency converter for satellite broadcasting reception, the components 51 to 74 thereof are connected to one another as shown in FIG. 3.
The frequency converter for satellite broadcasting reception having the above-mentioned configuration is operated as follows.
When a satellite broadcasting receiving antenna receives a satellite broadcasting wave (having a frequency within a range of 10.7 GHz to 12.75 GHz), a horizontally polarized signal of the satellite broadcasting wave is supplied to the first signal input terminal 71, and a vertically polarized signal thereof is supplied to the second signal input terminal 72. The horizontally polarized signal is amplified by the horizontally-polarized-signal amplifier 51 and is divided into two signals by the first signal splitter 53. Meanwhile, the vertically polarized signal is amplified by the vertically-polarized signal amplifier 52 and is divided into two signals by the second signal splitter 54. Then, signals in a predetermined frequency band are selected from one horizontally-polarized signal and one vertically-polarized signal, by the first band pass filter group 55, and the selected signals are supplied to the frequency mixing stages 57a and 57b of the first frequency converting unit 57. Similarly, signals in a predetermined frequency band are selected from the other horizontally-polarized signal and the other vertically-polarized signal, by the second band pass filter group 56, and the selected signals are supplied to the frequency mixing stages 58a and 58b of the second frequency converting unit 58.
The frequency mixing stages 57a and 57b respectively mix the frequencies of the one horizontally-polarized signal and the one vertically-polarized signal with the frequency of a local oscillating signal (having a frequency of 9.75 GHz) output from the local oscillator 57c to generate frequency mixed signals. The first intermediate-frequency signal amplifier group 59 selectively amplifies difference frequency components (having a frequency within a range of 0.95 GHz to 2.15 GHz) of the generated frequency mixed signals, and supplies the amplified signals to the first signal splitter group 61 as the one horizontally-polarized intermediate-frequency signal and the one vertically-polarized intermediate-frequency signal. At this time, the first signal splitter group 61 divides the one horizontally-polarized intermediate-frequency signal and the one vertically-polarized intermediate-frequency signal into two horizontally-polarized intermediate-frequency signals and two vertically-polarized intermediate-frequency signals, and supplies one of the divided horizontally-polarized intermediate-frequency signals and one of the divided vertically-polarized intermediate-frequency signals to the 4 x 2 selector switch circuit 63 and the other of the divided horizontally-polarized intermediate-frequency signals and the other of the divided vertically-polarized intermediate-frequency signals to the 4 x 1 selector switch circuit 64. Similarly, the frequency mixing stages 58a and 58b respectively mix the frequencies of the other horizontally-polarized signal and the other vertically-polarized signal with the frequency of a local oscillating signal (having a frequency of 10.6 GHz) output from the local oscillator 58c to generate frequency mixed signals. The second intermediate-frequency signal amplifier group 60 selectively amplifies difference frequency components (having a frequency within a range of 0.95 GHz to 2.15 GHz) of the generated frequency mixed signals, and supplies the amplified signals to the second signal splitter group 62 as the other horizontally-polarized intermediate-frequency signal and the other vertically-polarized intermediate-frequency signal. At this time, the second signal splitter group 62 divides the other horizontally-polarized intermediate-frequency signal and the other vertically-polarized intermediate-frequency signal into two horizontally-polarized intermediate-frequency signals and two vertically-polarized intermediate-frequency signals, and supplies one of the divided horizontally-polarized intermediate-frequency signals and one of the divided vertically-polarized intermediate-frequency signals to the 4 x 2 selector switch circuit 63 and the other of the divided horizontally-polarized intermediate-frequency signals and the other of the divided vertically-polarized intermediate-frequency signals to the 4 x 1 selector switch circuit 64.
The 4 x 2 selector switch circuit 63 selects two intermediate-frequency signals from the four supplied intermediate-frequency signals, and supplies the selected intermediate-frequency signals to the third frequency-converting unit 65 and the fourth frequency-converting unit 66. The third frequency-converting unit 65 generates a frequency mixed signal of the intermediate-frequency signal and a local oscillating signal output from the local oscillator 65b, and the fourth frequency-converting unit 66 generates a frequency mixed signal of the intermediate-frequency signal and a local oscillating signal output from the local oscillator 66b. Next, the third band pass filter group 67 selects one frequency component (having a frequency of 0.95 GHz to 2.15 GHz) corresponding to one broadcasting channel from each of the frequency mixed signals output from the third frequency-converting unit 65 and the fourth frequency-converting unit 66. The signal synthesizer 68 synthesizes the selected frequency components to generate one broadcasting channel signal. The synthesized broadcasting channel signal is amplified by the first output amplifier 69 and is then supplied to the first signal output terminal 73. Then, the signal is supplied from the first signal output terminal 73 to two conventional tuners through a satellite channel router (SCR).
Meanwhile, the 4 x 1 selector switch circuit 64 selects one intermediate-frequency signal from the four supplied intermediate-frequency signals. The selected intermediate-frequency signal is amplified by the second output amplifier 70 and is then supplied to the second output terminal 74. Then, the second output terminal 74 supplies the signal to one conventional tuner. Switching by the 4 x 2 selector switch circuit 63 and the 4 x 1 selector switch circuit 64 or the frequency switching of the local oscillating signal of the local oscillator 65b and the local oscillating signal of the local oscillator 66b is controlled on the basis of a control signal supplied from the corresponding tuners connected thereto.
The conventional frequency converter for satellite broadcasting reception meets satisfactory characteristics in functional aspect. However, since four paths are formed by the first band pass filter group 55, the second band pass filter group 56, the first frequency-converting unit 57, the second frequency-converting unit 58, the first intermediate-frequency signal amplifier group 59, the second intermediate-frequency signal amplifier group 60, the first signal splitter group 61, the 4 x 2 selector switch circuit 63, and the 4 x 1 selector switch circuit 64, the circuit configuration becomes complicated. Further, the complicated circuit configuration causes the number of required components to increase. Accordingly, the area of a space required for mounting the components increases, which makes it difficult to obtain a small frequency converter for satellite broadcasting reception and thus to reduce manufacturing costs.

SUMMARY OF THE INVENTION

The invention is made in view of such technical problems, and it is an object of the invention to provide a frequency converter for satellite broadcasting reception that has a simple circuit configuration, a small number of components, a small size, and low manufacturing costs.
In order to achieve the object, according to a first aspect of the invention, a frequency converter for satellite broadcasting reception includes: a first frequency-converting unit that converts the frequencies of horizontally-polarized signals of a plurality of channels and the frequencies of vertically-polarized signals of a plurality of channels of received satellite broadcasting waves to generate horizontally-polarized intermediate-frequency signals of a plurality of channels and vertically-polarized intermediate-frequency signals of a plurality of channels; a signal selecting unit that selects one horizontally-polarized or vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels output from the first frequency-converting unit; and a second frequency-converting unit that converts the one intermediate-frequency signal of the one channel output from the signal selecting unit into a first or second intermediate-frequency signal of another channel having a different frequency from that of the one intermediate-frequency signal. In the frequency converter, the first or second intermediate-frequency signal of another channel output from the second frequency-converting unit is supplied to a broadcasting signal receiver.
Further, in order to achieve the object, according to a second aspect of the invention, a frequency converter for satellite broadcasting reception includes: a first frequency-converting unit that converts the frequencies of horizontally-polarized signals of a plurality of channels and the frequencies of vertically-polarized signals of a plurality of channels of received satellite broadcasting waves to generate horizontally-polarized intermediate-frequency signals of a plurality of channels and vertically-polarized intermediate-frequency signals of a plurality of channels; a first signal selecting unit that selects one horizontally-polarized or vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels output from the first frequency-converting unit; a second signal selecting unit that selects one horizontally-polarized intermediate-frequency signal of one channel and one vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels, respectively; a second frequency-converting unit that converts the one intermediate-frequency signal of the one channel output from the first signal selecting unit into a first or second intermediate-frequency signal of another channel having a different frequency from that of the one intermediate-frequency signal; and a third frequency-converting unit that converts the one horizontally-polarized intermediate-frequency signal of the one channel and the one vertically-polarized intermediate-frequency signal of the one channel output from the second signal selecting unit into another horizontally-polarized intermediate-frequency signal and another vertically-polarized intermediate-frequency signal within a narrower frequency band. In the frequency converter, the first or second intermediate-frequency signal of the one channel output from the second frequency-converting unit is supplied to a broadcasting signal receiver, and the horizontally-polarized intermediate-frequency signal and the vertically-polarized intermediate-frequency signal output from the third frequency-converting unit are added, and the added signal is supplied to the broadcasting signal receiver.
In order to achieve the object, according to a third aspect of the invention, a frequency converter for satellite broadcasting reception includes: a first frequency-converting unit that converts the frequencies of horizontally-polarized signals of a plurality of channels and the frequencies of vertically-polarized signals of a plurality of channels of received satellite broadcasting waves to generate horizontally-polarized intermediate-frequency signals of a plurality of channels and vertically-polarized intermediate-frequency signals of a plurality of channels; a signal selecting unit that selects one horizontally-polarized or vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels output from the first frequency-converting unit; a second frequency-converting unit that converts the one horizontally-polarized or vertically-polarized intermediate-frequency signal of the one channel output from the signal selecting unit into a first or second intermediate-frequency signal of another channel having a different frequency from that of the one intermediate-frequency signal; and another second frequency-converting unit that converts of the one horizontally-polarized or vertically-polarized intermediate-frequency signal of the one channel output from the signal selecting unit into a third or fourth intermediate-frequency signal of another channel having a different frequency from that of the one intermediate-frequency signal. In the frequency converter, the first or second intermediate-frequency signal of another channel output from the second frequency-converting unit and the third or fourth intermediate-frequency signal of another channel output from another second frequency-converting unit are supplied to a broadcasting signal receiver.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the configuration of a main part of a frequency converter for satellite broadcasting reception according to a first embodiment of the invention;
FIG. 2 is a block diagram showing the configuration of a main part of a frequency converter for satellite broadcasting reception according to a second embodiment of the invention; and
FIG. 3 is a block diagram showing the configuration of a frequency converter for satellite broadcasting reception according to the related art.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Hereinafter, embodiments according to the invention will be described with reference to the accompanying drawings.
FIG. 1 is a block diagram showing the configuration of a main part of a frequency converter for satellite broadcasting reception according to a first embodiment of the invention.
As shown in FIG. 1, the frequency converter for satellite broadcasting reception according to this embodiment includes: a horizontally-polarized-signal amplifier 1; a vertically-polarized-signal amplifier 2; a first band pass filter 3; a second band pass filter 4; a frequency converting unit (first frequency-converting unit) 5; a horizontally-polarized intermediate-frequency signal amplifier 6; a vertically-polarized intermediate-frequency signal amplifier 7; a horizontally-polarized-signal splitter 8; a vertically-polarized-signal splitter 9; a 2 x 2 selector switch circuit 10; a 2 x 1 selector switch circuit 11; a frequency converting unit (third frequency-converting unit) 12; a frequency converting unit (third frequency-converting unit) 13; a third band pass filter 14; a fourth band pass filter 15; a signal synthesizer 16; a first output amplifier 17; a frequency converting unit (second frequency-converting unit) 18; a second output amplifier 19; a microcomputer 20; a selector switch 21; a horizontally-polarized-signal input terminal 22; a vertically-polarized-signal input terminal 23; a first signal output terminal 24; a second signal output terminal 25; and a control terminal 26.
In this case, the horizontally-polarized-signal amplifier 1 has two cascaded amplifiers 1a and 1b and the vertically-polarized-signal amplifier 2 has two cascaded amplifiers 2a and 2b. The frequency converting unit 5 has two frequency mixing stages 5a and 5b, one local oscillator 5c, and one buffer amplifier 5d. The frequency converting unit 12 has a frequency mixing stage 12a and a local oscillator 12b, and the frequency converting unit 13 has a frequency mixing stage 13a and a local oscillator 13b. The frequency converting unit 18 has a frequency mixing stage 18a and two local oscillators 18b and 18c. The 2 x 2 selector switch circuit 10 selectively connects two input circuits to two output circuits, and the 2 x 1 selector switch circuit 11 selectively connects two input circuits to one output circuit.
An input port of the horizontally-polarized-signal amplifier 1 is connected to the horizontally-polarized-signal input terminal 22, and an output port thereof is connected to an input port of the first band pass filter 3. An input port of the vertically-polarized-signal amplifier 2 is connected to the vertically-polarized-signal input terminal 23, and an output port thereof is connected to an input port of the second band pass filter 4. In the frequency mixing stage 5a of the frequency converting unit 5, a first input port is connected to an output port of the first band pass filter 3, a second input port is connected to an output port of the local oscillator 5c through the buffer amplifier 5d, and an output port is connected to an input port of the horizontally-polarized intermediate-frequency signal amplifier 6. In the frequency mixing stage 5b, a first input port is connected to an output port of the second band pass filter 4, a second input port is connected to an output port of the local oscillator 5c through the buffer amplifier 5d, and an output port is connected to an input port of the vertically-polarized intermediate-frequency signal amplifier 7. In the horizontally-polarized-signal splitter 8, an input port is connected to an output port of the horizontally-polarized intermediate-frequency signal amplifier 6, a first output port is connected to a first input port of the 2 x 2 selector switch circuit 10, and a second output port is connected to a first input port of the 2 x 1 selector switch circuit 11. In the vertically-polarized-signal splitter 9, an input port is connected to an output port of the vertically-polarized intermediate-frequency signal amplifier 7, a first output port is connected to a second input port of the 2 x 2 selector switch circuit 10, and a second output port is connected to a second input port of the 2 x 1 selector switch circuit 11.
In the frequency mixing stage 12a of the frequency converting unit 12, a first input port is connected to a first output port of the 2 x 2 selector switch circuit 10, a second input port is connected to an output port of the local oscillator 12b, and an output terminal is connected to an input port of the third band pass filter 14. In the frequency mixing stage 13a of the frequency converting unit 13, a first input port is connected to a second output port of the 2 x 2 selector switch circuit 10, a second input port is connected to an output port of the local oscillator 13b, and an output port is connected to an input port of the fourth band pass filter 15. In the signal synthesizer 16, a first input port is connected to an output port of the third band pass filter 14, a second input port is connected to an output port of the fourth band pass filter 15, and an output port is connected to an input port of the first output amplifier 17. An output port of the first output amplifier 17 is connected to the first signal output terminal 24. In the frequency mixing stage 18a of the frequency converting unit 18, a first input port is connected to an output port of the 2 x 1 selector switch circuit 11, a second input port is connected to output ports of the two local oscillators 18b and 18c, and an output port is connected to an input port of the second output amplifier 19. An output port of the second output amplifier 19 is connected to the second signal output terminal 25. Further, control ports of the two local oscillators 18b and 18c are connected to the corresponding switching terminals of the selector switch 21, respectively, and a control port of the microcomputer 20 is connected to the control terminal 26. In addition, a control output port is connected to a switchable terminal of the selector switch 21.
The frequency converter for satellite broadcasting reception having the above-mentioned configuration is operated as follows.
When a satellite broadcasting receiving antenna (not shown in Fig. 1) receives satellite broadcasting waves (having a frequency within a range of 10.7 GHz to 12.75 GHz), a horizontally polarized signal H of the satellite broadcasting wave is supplied to the first input terminal 22, and a vertically polarized signal V of the satellite broadcasting wave is supplied to the second input terminal 23. The horizontally polarized signal is amplified by the horizontally-polarized-signal amplifier 1, and a predetermined frequency band is selected from the amplified signal by the first band pass filter 3. Then, the signal is supplied to the frequency mixing stage 5a of the frequency converting unit 5. Meanwhile, the vertically polarized signal is amplified by the vertically-polarized-signal amplifier 2, and a predetermined frequency band is selected from the amplified signal by the second band pass filter 4. Then, the signal is supplied to the frequency mixing stage 5b of the frequency converting unit 5.
The frequency mixing stage 5a mixes the frequency of the supplied horizontally polarized signal with the frequency of a local oscillating signal (having a frequency of 13.25 GHz) supplied from the local oscillator 5c through the buffer amplifier 5d to generate a frequency mixed signal. Meanwhile, the frequency mixing stage 5b mixes the frequency of the supplied vertically polarized signal with the frequency of the local oscillating signal supplied from the local oscillator 5c through the buffer amplifier 5d to generate a frequency mixed signal. A difference frequency component (having a frequency within a range of 0.5 GHz to 2.55 GHz) of the frequency mixed signal output from the frequency mixing stage 5a is selectively amplified by the horizontally-polarized intermediate-frequency signal amplifier 6 to obtain a horizontally-polarized intermediate-frequency signal, which is supplied to the horizontally-polarized-signal splitter 8. The horizontally-polarized-signal splitter 8 splits the horizontally-polarized intermediate-frequency signal into two signals, and supplies the two horizontally-polarized intermediate-frequency signals to the 2 x 2 selector switch circuit 10 and the 2 x 1 selector switch circuit 11, respectively. Similarly, a difference frequency component (having a frequency within a range of 0.5 GHz to 2.55 GHz) of the frequency mixed signal output from the frequency mixing stage 5b is selectively amplified by the vertically-polarized intermediate-frequency signal amplifier 7 to obtain a vertically-polarized intermediate-frequency signal, which is supplied to the vertically-polarized-signal splitter 9. The vertically-polarized-signal splitter 9 splits the vertically-polarized intermediate-frequency signal into two signals and supplies the two vertically-polarized intermediate-frequency signals to the 2 x 2 selector switch circuit 10 and the 2 x 1 selector switch circuit 11, respectively.
The 2 x 2 selector switch circuit 10 is supplied with the horizontally-polarized intermediate-frequency signals of a plurality of channels and the vertically-polarized intermediate-frequency signals of a plurality of channels, and selects the intermediate-frequency signals of two channels among them. Then, the 2 x 2 selector switch circuit 10 supplies the selected intermediate frequency signals to the frequency mixing stage 12a of the frequency converting unit 12 and the frequency mixing stage 13a of the frequency converting unit 13, respectively. The frequency mixing stage 12a mixes the supplied intermediate-frequency signal with the local oscillating signal output from the local oscillator 12b to generate a frequency mixed signal, and the frequency mixing stage 13a mixes the supplied intermediate-frequency signal with the local oscillating signal output from the local oscillator 13b to generate a frequency mixed signal. The third band pass filter 14 filters the frequency mixed signal supplied from the frequency mixing stage 12a to select a predetermined frequency component (having a frequency of 1.4 GHz to 1.75 GHz), and supplies the selected broadcasting channel signal to the signal synthesizer 16. Meanwhile, the fourth band pass filter 15 filters the frequency mixed signal supplied from the frequency mixing stage 13a to select a predetermined frequency component (having a frequency of 1.4 GHz to 1.75 GHz), and supplies the selected broadcasting channel signal to the signal synthesizer 16. The signal synthesizer 16 synthesizes the two supplied broadcast channel signals, and the synthesized broadcast signal is supplied to the first output amplifier 17. Then, the first output amplifier 17 amplifies the supplied signal and then supplies the amplified signal to the first signal output terminal 24. The signal is supplied from the first signal output terminal 24 to two conventional antennas through a satellite channel router (SCR).
Further, the 2 x 1 selector switch circuit 11 is supplied with the horizontally-polarized intermediate-frequency signals of a plurality of channels and the vertically-polarized intermediate-frequency signals of a plurality of channels, and selects the intermediate-frequency signal of one channel among them. Then, the 2 x 1 selector switch circuit 11 supplies the selected intermediate frequency signal to the frequency mixing stage 18a of the frequency converting unit 18. The frequency mixing stage 18a mixes the frequency of the supplied intermediate-frequency signal with the frequency of the local oscillating signal (having a frequency of 2.65 GHz) output from the local oscillator 18b or the frequency of the local oscillating signal output (having a frequency of 3.5 GHz) from the local oscillator 18c to generate a frequency mixed signal as an output. The second output amplifier 19 amplifies the generated frequency mixed signal to generate an intermediate-frequency signal of one channel, and supplies the signal to the second output terminal 25. Then, the signal is supplied from the second signal output terminal 25 to one conventional antenna.
In this case, the local oscillating signal supplied to the frequency mixing stage 18a is the local oscillating signal supplied from the local oscillators 18b and 18c selected by the selector switch 21. The selection of the selector switch 21 is controlled by the microcomputer 20 operated on the basis of a control signal supplied to the control terminal 26. Further, the switching of the 2 x 2 selector switch circuit 10 and the 2 x 1 selector switch circuit 11 or frequency switching between the local oscillating signal of the local oscillator 12b and the local oscillating signal of the local oscillator 13b is performed on the basis of a control signal which is supplied from a conventional tuner connected to the first output terminal 24.
Next, FIG. 2 is a block diagram showing the configuration of a main part of a frequency converter for satellite broadcasting reception according to a second embodiment of the invention.
As shown in FIG. 2, the frequency converter (hereinafter, referred to as a second frequency converter) for satellite broadcasting reception according to the second embodiment includes: a first part having the frequency converting unit (the second frequency-converting unit) 18, the second output amplifier 19, the microcomputer 20, the selector switch 21, and the second signal output terminal 25 which are used for the frequency converter (hereinafter, referred to as a first frequency converter) for satellite broadcasting reception shown in FIG. 1; and a second part which is arranged in parallel to the first part and has the same structure as that of the first part. The second part has a frequency converting unit (a second frequency-converting unit) 27, a second output amplifier 28, a microcomputer 29, a selector switch 30, and a second signal output terminal 31. In the second frequency converter, since the first part and the second part are arranged in parallel to each other, a 2 x 2 selector switch circuit 32 is used instead of the 2 x 1 selector switch circuit 11 used in the first frequency converter. Except for the above-mentioned point, the second frequency converter has the same configuration as that of the first frequency converter. Therefore, in the configuration of the second frequency converter shown in FIG. 2, the same components as those in the first
frequency converter shown in FIG. 1 are denoted by the same reference numerals, and a description thereof will be omitted.
The operation of the second component part is the same as that of the first part because the configuration of the second part is the same as that of the first part. Further, the configuration of the second frequency converter is similar to that of the first frequency converter except that the second frequency converter further includes the second part. Therefore, the operation of the second frequency converter is substantially the same as that of the first frequency converter, and thus a description thereof will be omitted.
As described above, according to the above-described embodiments, the frequency converter for satellite broadcasting reception has a simpler configuration. Therefore, it is possible to obtain a frequency converter for satellite broadcasting reception capable of reducing the number of components, of receiving signals in a wide frequency band, and of being manufactured in a small size at low cost.
As described above, the frequency converter for satellite broadcasting reception according to the first aspect includes the signal selecting unit and the second frequency-converting unit. The signal selecting unit is supplied with the horizontally-polarized intermediate-frequency signals of a plurality of channels and the vertically-polarized intermediate-frequency signals of a plurality of channels. The second frequency-converting unit converts one intermediate-frequency signal of one channel output from the signal selecting unit into a first intermediate-frequency signal of another channel corresponding to a high channel having a different frequency from that of the one intermediate-frequency signal, or a second intermediate-frequency signal of another channel corresponding to a low channel having a different frequency from that of the one intermediate-frequency signal. In the frequency converter, the first or second intermediate-frequency signal of another channel output from the second frequency-converting unit is supplied to a conventional broadcasting signal receiver. Therefore, it is possible to obtain a frequency converter for satellite broadcasting reception that has a simple circuit configuration, a small number of components, a small size and low manufacturing costs and can receive broadcasting signals in a wide frequency band.
According to the frequency converter for satellite broadcasting reception according to the second aspect includes the first signal selecting unit, the second frequency-converting unit, the second signal selecting unit, and the third frequency-converting unit. The signal selecting unit is supplied with the horizontally-polarized intermediate-frequency signals of a plurality of channels and the vertically-polarized intermediate-frequency signals of a plurality of channels. The second frequency-converting unit converts one intermediate-frequency signal of one channel output from the signal selecting unit into a first intermediate-frequency signal of another channel corresponding to a high channel having a different frequency from that of the one intermediate-frequency signal, or a second intermediate-frequency signal of another channel corresponding to a low channel having a different frequency from that of the one intermediate-frequency signal. The second signal selecting unit is supplied with the two intermediate-frequency signals. The third frequency-converting unit converts the one horizontally-polarized intermediate-frequency signal of the one channel and the one vertically-polarized intermediate-frequency signal of the one channel output from the second signal selecting unit into another horizontally-polarized intermediate-frequency signal and another vertically-polarized intermediate-frequency signal within a narrower frequency band. The horizontally-polarized intermediate-frequency signal and the vertically-polarized intermediate-frequency signal output from the third frequency converting unit are added, and the added signal is supplied to the conventional broadcasting signal receiver. Therefore, similar to the first aspect, it is possible to obtain a frequency converter for satellite broadcasting reception that has a simple circuit configuration, a small number of components, a small size and low manufacturing costs and can receive broadcasting signals in a wide frequency band.
The frequency converter for satellite broadcasting reception according to the third aspect includes the signal selecting unit, one second frequency-converting unit, and another second frequency-converting unit. The signal selecting unit is supplied with the horizontally-polarized intermediate-frequency signals of a plurality of channels and the vertically-polarized intermediate-frequency signals of a plurality of channels. The one second frequency-converting unit converts one intermediate-frequency signal of one channel output from the signal selecting unit into a first intermediate-frequency signal of another channel corresponding to a high channel having a different frequency from that of the one intermediate-frequency signal, or a second intermediate-frequency signal of another channel corresponding to a low channel having a different frequency from that of the one intermediate-frequency signal. In the frequency converter, the first or second intermediate-frequency signal of another channel output from the one second frequency-converting unit is supplied to a conventional broadcasting signal receiver. At the same time, another second frequency-converting unit converts the one intermediate-frequency signal of the one channel output from the signal selecting unit into a third intermediate-frequency signal of another channel corresponding to a high channel having a different frequency from that of the one intermediate-frequency signal, or a fourth intermediate-frequency signal of another channel corresponding to a low channel having a different frequency from that of the one intermediate-frequency signal. The third or fourth intermediate-frequency signal of another channel output from another second frequency-converting unit is supplied to the conventional broadcasting signal receiver. Therefore, similar to the first and second aspects, it is possible to obtain a frequency converter for satellite broadcasting reception that has a simple circuit configuration, a small number of components, a small size and low manufacturing costs and can receive broadcasting signals in a wide frequency band.

Claims

A frequency converter for satellite broadcasting reception comprising:
a first frequency-converting unit that converts the frequencies of horizontally-polarized signals of a plurality of channels and the frequencies of vertically-polarized signals of a plurality of channels of received satellite broadcasting waves to generate horizontally-polarized intermediate-frequency signals of a plurality of channels and vertically-polarized intermediate-frequency signals of a plurality of channels;

a signal selecting unit that selects one horizontally-polarized or vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels output from the first frequency-converting unit; and

a second frequency-converting unit that converts the one intermediate-frequency signal of the one channel output from the signal selecting unit into a first or second intermediate-frequency signal of another channel having a different frequency from that of the one intermediate-frequency signal,

wherein the first or second intermediate-frequency signal of another channel output from the second frequency-converting unit is supplied to a broadcasting signal receiver.
A frequency converter for satellite broadcasting reception comprising:
a first frequency-converting unit that converts the frequencies of horizontally-polarized signals of a plurality of channels and the frequencies of vertically-polarized signals of a plurality of channels of received satellite broadcasting waves to generate horizontally-polarized intermediate-frequency signals of a plurality of channels and vertically-polarized intermediate-frequency signals of a plurality of channels;

a first signal selecting unit that selects one horizontally-polarized or vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels output from the first frequency-converting unit;

a second signal selecting unit that selects one horizontally-polarized intermediate-frequency signal of one channel and one vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels, respectively;

a second frequency-converting unit that converts the one intermediate-frequency signal of the one channel output from the first signal selecting unit into a first or second intermediate-frequency signal of another channel having a different frequency from that of the one intermediate-frequency signal; and

a third frequency-converting unit that converts the one horizontally-polarized intermediate-frequency signal of the one channel and the one vertically-polarized intermediate-frequency signal of the one channel output from the second signal selecting unit into another horizontally-polarized intermediate-frequency signal and another vertically-polarized intermediate-frequency signal within a narrower frequency band,

wherein the first or second intermediate-frequency signal of the one channel output from the second frequency-converting unit is supplied to a broadcasting signal receiver, and

the horizontally-polarized intermediate-frequency signal and the vertically-polarized intermediate-frequency signal output from the third frequency-converting unit are added, and the added signal is supplied to the broadcasting signal receiver.
A frequency converter for satellite broadcasting reception comprising:
a first frequency-converting unit that converts the frequencies of horizontally-polarized signals of a plurality of channels and the frequencies of vertically-polarized signals of a plurality of channels of received satellite broadcasting waves to generate horizontally-polarized intermediate-frequency signals of a plurality of channels and vertically-polarized intermediate-frequency signals of a plurality of channels;

a signal selecting unit that selects one horizontally-polarized or vertically-polarized intermediate-frequency signal of one channel from the horizontally-polarized intermediate-frequency signals of the plurality of channels and the vertically-polarized intermediate-frequency signals of the plurality of channels output from the first frequency-converting unit;

a second frequency-converting unit that converts the one horizontally-polarized or vertically-polarized intermediate-frequency signal of the one channel output from the signal selecting unit into a first or second intermediate-frequency signal of another channel having a different frequency from that of the one intermediate-frequency signal; and

another second frequency-converting unit that converts of the one horizontally-polarized or vertically-polarized intermediate-frequency signal of the one channel output from the signal selecting unit into a third or fourth intermediate-frequency signal of another channel having a different frequency from that of the one intermediate-frequency signal,

wherein the first or second intermediate-frequency signal of another channel output from the second frequency-converting unit and the third or fourth intermediate-frequency signal of another channel output from another second frequency-converting unit are supplied to a broadcasting signal receiver.