JPH0786979A - Shf receiver - Google Patents

Abstract

PURPOSE:To convert the frequency of an outdoor unit without extending a cable by operating a local oscillator A or B by the outdoor unit corresponding to an operating voltage A or B supplied from an indoor unit via a coaxial cable. CONSTITUTION:The outdoor unit 2 converts a broadcast signal SSHF from an antenna 1 to a signal SUHF, which is supplied to the indoor unit 4 via the coaxial cable 3. A power source circuit 27 in the unit 4 supplies a power source required for the inside, and a regulator 28 outputs a voltage +B of 10 or 15V by selecting a reference voltage VRH or VRL by a switch circuit 29. A regulator 13 in the unit 2 supplies the voltage +B to each internal circuit by changing the voltage to a constant voltage via the cable 3, and a level detection circuit 15 outputs a signal Sd based on the voltage +B of 10 or 15V. A switch circuit 14 operates the local oscillator 9L or 9R corresponding to the signal Sd, and a mixer 8 outputs a signal SUHF of a first or second band. In this way, the frequency conversion of the unit 2 can be performed without providing a cable separately.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an SHF receiver for receiving SHF broadcasting signals from broadcasting satellites, for example.

[0002]

2. Description of the Related Art An SHF receiver for receiving an SHF broadcast signal from a broadcasting satellite is provided outdoors with an antenna 1 as shown in FIG. 3, for example, and the SHF radio wave captured by the antenna 1 is converted into a UHF band. An outdoor unit 2 for frequency conversion and amplification, and an outdoor unit 2 installed indoors
A signal converted into the UHF band is supplied via the coaxial cable 3 and is composed of an indoor unit 4 for extracting a video signal and an audio signal to be supplied to the television receiver 5.

By the way, SHF broadcasting includes, for example, low power broadcasting (reception frequency 11.7 to 12.2 GHz) and high power broadcasting (reception frequency 12.2 to 12.7 GHz).
Is being considered.

[0004]

However, in the SHF receiver described above, if the local oscillation frequency in the outdoor unit 2 is not switched, the frequency is 500 MH.
Only z can take a band. Therefore, it is necessary to switch the local oscillation frequency in the outdoor unit 2 in order to receive the two broadcasts having different bands.

For this switching, for example, in addition to the coaxial cable 3, a cable for local oscillation frequency control may be separately provided from the indoor unit 4 to the outdoor unit 2 and control may be performed through this cable. However, it is not preferable to provide a plurality of cables between the outdoor unit 2 and the indoor unit 4 from the viewpoint of signal transmission, and the number of terminals of the outdoor unit 2 increases, and for example, from the viewpoint of airtightness for preventing rainwater leakage. Is also not preferable.

In view of the above points, the present invention provides an SHF receiver capable of receiving the SHF signal of the first band and the SHF signal of the second band by increasing the cable between the outdoor unit and the indoor unit. Another object of the present invention is to propose an SHF receiver capable of favorably performing switching according to the reception of SHF signals in the first and second bands of the local oscillation frequency in the frequency conversion means of the outdoor unit.

[0007]

SUMMARY OF THE INVENTION The present invention is an SHF receiver capable of receiving a SHF signal in a first band and a SHF signal in a second band, and receiving the SHF signal in the first and second bands. The indoor unit 4 including the operating voltage generating means 27, 28, 29 for generating the first and second operating voltages according to the above, the mixer 8 to which the SHF signals of the first and second bands are supplied, and the first And frequency conversion means FC for obtaining a signal in the UHF band from the mixer 8 by providing first and second local oscillators 9L and 9H for supplying a local oscillation signal to the mixer 8 in response to the SHF signal in the second band. And receiving the first and second operating voltages from the operating voltage generating means 27, 28, 29 of the indoor unit 4 through the single coaxial cable 3, and detecting the difference between the first and second operating voltages, In response to the detection of the first and second operating voltages Te first and second local oscillator 9
An outdoor unit 2 having an operating voltage detecting means 15 for selectively controlling L and 9H into an operating state, and a UHF band signal from the frequency converting means FC of the outdoor unit 2 is transmitted indoors through a coaxial cable 3. It is adapted to be supplied to the unit 4.

[0008]

According to the present invention, the first and second operating voltages from the operating voltage generating means 27, 28, 29 of the indoor unit 4 are supplied to the operating voltage detecting means 15 of the outdoor unit 2 through the coaxial cable 3. To do. In this way, the operating voltage detecting means 15 detects the difference between the first and second operating voltages, and in response to the detection of the first and second operating voltages, the first operating voltage is detected.
And the second local oscillators 9L and 9H are selectively controlled to be in the operating state. Then, the frequency conversion means F of the outdoor unit 2
The UHF band signal from C is supplied to the indoor unit 4 through the coaxial cable 3.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, parts corresponding to those in FIG. 3 are designated by the same reference numerals.

In the figure, the SHF broadcast signal S _SHF captured by the antenna 1 is converted from a circular polarization to a linear polarization by a circular polarization-linear polarization converter 6 which constitutes the outdoor unit 2, and a high frequency amplifier is further provided. It is supplied to the mixer 8 that constitutes the frequency converter FC via 7.

Further, 9L and 9H are local oscillators constituting the frequency converter FC, respectively, for example 10.70.
5 GHz (for low-power broadcasting reception) and 11.2 GHz
The frequency signals (for receiving high-power broadcasting) are generated, and the frequency signals output from each are supplied to the mixer 8. Then, a signal S _UHF whose frequency is converted to the UHF band is obtained from the mixer 8 and is supplied to the output terminal 12 via the intermediate frequency amplifier 10 and the DC blocking capacitor 11.

Further, 13 is a regulator, which is stabilized by the voltage + B supplied to the terminal 12 from the indoor unit 4 via the coaxial cable 3. As will be described later, the voltage + B supplied to the terminal 12 is, for example, when receiving low power broadcasting (11.7 to 12.2 GHz) and high power broadcasting (12.2 to 12.7 GHz), respectively. It is set to + 10V and + 15V. The voltage stabilized by the regulator 13 to a predetermined voltage is supplied to the high frequency amplifier 7 and the intermediate frequency amplifier 10, and is also supplied to the oscillators 9L and 9H via the switch circuit 14.

Reference numeral 15 is a level detection circuit, which is supplied with the voltage + B supplied to the terminal 12 and whose level is +.
Whether it is 10V or + 15V is detected. Then, the detection signal Sd is supplied to the switch circuit 14 as a switching control signal. The switch circuit 14 operates when the voltage + B is + 10V, that is, low power broadcasting (1
Oscillator 9L when receiving 1.7 to 12.2 GHz)
When the voltage + B is + 15V while being switched to the side, that is, high power broadcasting (12.2 to 12.7 GHz)
Is received, it is switched to the oscillator 9H side.

Therefore, when receiving a low power broadcast, an operating voltage is supplied from the regulator 13 to the oscillator 9L, and a frequency signal of 10.705 GHz is supplied from the oscillator 9L to the mixer 8 so that the low power broadcast is received. To be done. On the other hand, when receiving high power broadcasting, the operating voltage is supplied from the regulator 13 to the oscillator 9H,
A frequency signal of 11.2 GHz is supplied from the oscillator 9H to the mixer 8 so that the mixer 8 is brought into a high power broadcasting reception state.

The signal S _{UHF, which} has been frequency-converted to the UHF band and is supplied to the terminal 12 of the outdoor unit 2, is the coaxial cable 3, the input terminal 16 and the DC blocking capacitor 1.
It is supplied to the tuner 18 constituting the indoor unit 4 via 7.

In the tuner 18, the broadcast of a predetermined channel is selected by the control of the channel selector 19, and the intermediate frequency signal (FM signal) S _IF of the selected broadcast is obtained at the output side thereof. This signal S _IF is supplied to the FM detector 23 via the series circuit of the AGC amplifier 20, the bandpass filter 21 and the limiter 22. From the detector 23, for example, as shown in FIG.
Video signal S _V consisting of color signal C and 4-phase phase modulation (4P
_A combined signal with the SK) audio signal S _A ′ is obtained and supplied to the video amplifier 24 and the audio processor 25.

The video signal S _V is amplified and obtained from the video amplifier 24 and the audio processor 25 is also provided.
From the audio signal S _A is obtained.

The video signal S _V from the video amplifier 24 and the audio signal S _A from the audio processor 25 are RF.
It is supplied to the converter 26, and the television signal S _RF matched with, for example, an empty channel is obtained from the converter 26.

Further, in the indoor unit 4, reference numeral 27 denotes a power supply circuit, which supplies a required voltage to each part of the indoor unit 4 and a predetermined voltage to the regulator 28. The regulator 28 is supplied with different reference voltages V _RL and V _RH via the switch circuit 29 when receiving low power broadcasting and when receiving high power broadcasting, respectively. Then, at the output side of the regulator 28, a voltage + B of, for example, +10 V for low power broadcasting and +15 V for high power broadcasting is obtained. The voltage + B is supplied to the terminal 12 of the outdoor unit 2 via the AC blocking coil 30, the terminal 16 and the coaxial cable 3 as described above.

In this example, when receiving low-power broadcasting (11.7 to 12.2 GHz) configured in this way, it is supplied from the indoor unit 4 to the terminal 12 of the outdoor unit 2 via the coaxial cable 3. Voltage + B is, for example, + 10V
And the local oscillator 9 is controlled by the level detection circuit 15.
The operating voltage is supplied to L, and the mixer 8 receives 10.705G
A frequency signal of Hz is supplied, and the outdoor unit 2 is set to a low power broadcast receiving state. On the other hand, when receiving high power broadcasting (12.2 to 12.7 GHz), the voltage + B similarly supplied to the terminal 12 of the outdoor unit 2 is set to +15 V, for example, and the local oscillator 9H is controlled by the level detection circuit 15. Operating voltage is supplied to the mixer 8
A frequency signal of 1.2 GHz is supplied, and the mixer 8 is set to 1
The outdoor unit 2 is supplied with a 1.2 GHz frequency signal.
Is set to a high power broadcasting reception state. Therefore, in this example, both low power broadcasting and high power broadcasting can be received.

According to the present example, the cable between the outdoor unit 2 and the indoor unit 4 has the minimum required 1 as in the conventional case.
With only the coaxial cable 3 of the book, the reception band of the local oscillation frequency in the outdoor unit 2 can be switched without increasing the number of cables. Therefore, inconveniences in signal transmission and airtightness due to the increase in the number of cables cannot occur.

[0022]

According to the present invention described above, in the SHF receiver capable of receiving the SHF signal of the first band and the SHF signal of the second band, the number of cables between the outdoor unit and the indoor unit is increased. Without doing so, the switching according to the reception of the SHF signal of the first and second bands of the local oscillation frequency in the frequency conversion means of the outdoor unit can be favorably performed.
An HF receiver can be obtained. Therefore, inconvenience in terms of signal transmission and airtightness due to the increase in the number of cables does not occur.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a characteristic curve diagram for explaining the operation of the embodiment.

FIG. 3 is a block diagram showing an outline of a conventional SHF receiver.

[Explanation of symbols]

 1 Antenna 2 Outdoor Unit 3 Coaxial Cable 4 Indoor Unit FC Frequency Converter 8 Mixer 9L Local Oscillator 9H Local Oscillator 14 Switch Circuit 15 Level Detector 27 Power Supply Circuit 28 Regulator 29 Switch Circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenichiro Kumamoto 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Sony Corporation

Claims (1)

[Claims] 1. An SHF receiver capable of receiving a SHF signal of a first band and a SHF signal of a second band, wherein the first and second SHF signals according to the reception of the SHF signal of the first and second modes are provided. In response to the indoor unit including the operating voltage generating means for generating the operating voltage of 2, the mixer to which the SHF signals of the first and second bands are supplied, and the SHF signals of the first and second bands. The first and second local oscillators for supplying a local oscillation signal to the mixer, the frequency conversion means for obtaining a UHF band signal from the mixer, and the first for the operating voltage generation means of the indoor unit. And a second operating voltage through a single coaxial cable to detect the difference between the first and second operating voltages, and to detect the first and second operating voltages according to the detection of the first and second operating voltages. Selectively operating the second local oscillator And a outdoor unit and a operation voltage detection means for controlling the state, the UH than said frequency converting means of the outdoor unit
An SHF receiver characterized in that an F band signal is supplied to the indoor unit through the coaxial cable.