KR950003966B1 - Double lnb device - Google Patents

Abstract

A number of subscribers can be select and receive the hozizontal or vertical polarization satellite broadcasting signal with the common-used LNB apparatus. The apparatus processes the horizontal polarization signals (Hin) that is inputted to the first and the third middle amplifier (13,15) through a first distributer (11), vertical polarization signals (Vin) connected to the second and fourth middle amplifiers (14,16) through a second distributer (12), the outputs of the first to fourch middle amplifiers (13-16) amplified at each of the first and second last amplifier (A3, A3'), and the operation selecting signal of the first to fourth middle amplifiers (13-16) connected to a switch voltage generating unit (15) that generates the logic controlling voltage depending on the input of LNB power (VLP1, VLP2).

Description

Double LNB Device

1 is a circuit block diagram of a conventional double LNB apparatus.

2 is a circuit block diagram of a double LNB apparatus of the present invention.

3 is a detailed circuit diagram of an LNB device of the present invention.

4 is a truth store for explaining the operating state of the present invention.

* Explanation of symbols for the main parts of the drawings

Al, Al ': Ultra-short amplifier A3, A3': Termination amplifier

10: multi-switching amplifier 11, 12 distributor

13-16: interruption amplifier 17: switching voltage generator.

The present invention relates to a low noise block converter (LNB) device for receiving a satellite broadcast, wherein a plurality of satellite broadcast receivers sharing a single LNB device can select horizontal and vertically polarized satellite broadcast signals arbitrarily. A vertically polarized switchable double LNB apparatus.

Satellite broadcasting receiving system is divided into outdoor installation part and indoor installation part. The outdoor installation includes a para-blade antenna and an LNB device, and the indoor installation includes a BS tuner connected to the TV set.

In general, LNB devices are designed for either polarization only in horizontal or vertically polarized satellite broadcasting, but recently, they are designed to receive both horizontal and vertical polarized signals according to the demand of the consumer. This is commonly referred to as a double LNB device.

The double LNB device is composed of a low noise amplifier (LNA), a mixer, and an oscillator, and converts an RF satellite broadcast signal into an IF signal and supplies it to an indoor BS tuner.

The low noise amplifier comprises a three stage amplification circuit, an example of which is shown in FIG.

Where A _l , A ₂ and A ₃ are the first, middle and termination amplifiers for amplifying the horizontally polarized input signal (Hin), and A _l ', A ₂ ', A ₃ 'are the vertically polarized input signal (Vin). It is an ultra-short, interrupted, terminated amplifier for amplifying. This double LNB device installs two single LNAs for horizontal and vertical polarized signal amplification, each containing the first, interruption, termination amplifiers (A _l -A ₃ ) and (A _l '-A ₃ ') in a structure. Thus, the horizontally polarized signal is output at one port and the vertically polarized signal is output at the other port.

However, in the conventional double LNB device as described above, in order to receive a polarization broadcast desired by a plurality of satellite broadcasters, there has been a disadvantage in that a separate multi-switch is installed and operated by the LNB device installed outdoors.

It is an object of the present invention to provide a double LNB device that can receive a plurality of satellite broadcasts through one LNB device and can easily switch vertical and horizontal polarized broadcast signals indoors.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

2 is a circuit block diagram illustrating the concept of the present invention, in which the horizontal and vertical polarization input signals Hin and Vin are respectively input to the multi-switching amplifier 10 through the ultra short amplifiers A _l and A _l ′. In addition, the horizontal and vertical polarization signals switched and amplified by the multi-switching amplifier 10 are selectively output from the respective termination amplifiers A ₃ and A ₃ ′.

FIG. 3 is a detailed circuit diagram of the present invention, in which the horizontal polarization input signal Hin is amplified by the first first amplifier A _l and then passed through the first divider l1 to the first interruption amplifier 13 and the third middle only. Connected to the amplifier 15, the vertically polarized input signal Vin is amplified by the second ultra-short amplifier A ₁ ', and then passes through the second divider 12 to the second interrupt amplifier 14 and the fourth. It is configured to connect to be input to the interruption amplifier (16).

The first and second dividers 11 and 12 are configured by Wilkinson distribution circuits having good 3 dB loss and mutual isolation for horizontal and vertical polarized signals.

On the other hand, the output of the first interruption amplifier 13 and the second interruption amplifier l4 are commonly connected to be amplified and output from the first termination amplifier A ₃ , and the third interruption amplifier 15 and the fourth interruption. The output of the amplifier 16 is commonly configured to be amplified and output from the second terminal amplifier A ₃ ′.

The first to fourth interruption amplifiers 13-16 are amplifying transistors Q _{1 to} Q ₄ , pin diodes D _{1 to} D ₄ , bias resistors R _{1 to} R ₄ , and power noise shielding coils. (L ₁ -L ₄ ), and the power of these first-fourth interrupt amplifiers 13-16 is connected to be supplied from the switching voltage generation unit 17.

The switching voltage generator 17 receives the LNB powers VLP ₁ and VLP ₂ through a cable connecting the outdoor set and the indoor set, and controls the four kinds (ad) by using the voltage difference of the supply power. It consists of a universal logic circuit that carries a voltage output.

Referring to the operation and effects of the present invention configured as described above are as follows.

In FIG. 3, the l first stage amplifier (A _l) of the horizontally polarized wave signal (Hin) amplified may be divided in a first distributor 11 in the multi-switching amplifying unit 10 first stops the amplifier (13 has a 3dB loss ) And a third interrupt amplifier 15, respectively. In addition, the vertically polarized signal Vin amplified by the second ultrashort amplifier A ₁ 'is also distributed by the second divider 12 of the multi-switching amplifier 10 to have a 3dB loss and a second interrupt amplifier 14. Input to the fourth interruption amplifiers 16, respectively.

The first and second breaker amplifiers 13 and 14 and the thirteenth and four breaker amplifiers 15 and 16 may be divided into a first and a second divider according to whether power is supplied to terminals a and b and c and d, respectively. Amplifying the polarization signal from 11 and 12, for example, if the first-fourth interrupt amplifiers 13-16 require 9 V of power, the voltages are different from each other in the switching voltage generator 17. The logic of the powers VLP ₁ and VLP ₂ may be selectively output at each terminal ad.

Referring to FIG. 4, if all of the LNB powers VLP ₁ and VLP ₂ are provided at 13V from the indoor BS tuner side to the outdoor LNB, the terminals b and d of the switching voltage generator 17 9V is output and 0V is output at terminals a and c.

Therefore, since the driving voltage is applied only to the second and fourth breaker amplifiers 14 and 16, a vertical polarization signal is output to the output terminal of the first termination amplifier A ₃ , that is, the first output terminal out _l of the LNB. The vertical polarization signal is also output to the output terminal of the two-stage amplifier A ₃ ′, that is, the second output terminal out ₂ of the LNB.

In addition, when the LNB powers VLP ₁ and VLP ₂ are 13V and 18V, respectively, the second and third interrupt amplifiers 14 and 15 are driven, so that a vertical polarization signal is output to the first output terminal _l of the LNB, Horizontal polarization signals are output to the two output terminals (out ₂ ).

In addition, when the LNB powers VLP ₁ and VLP ₂ are 18V and 13V, respectively, only the first and fourth interrupt amplifiers 13 and 16 are driven. Accordingly, only the first and second output terminals (out _l and out ₂ ) of the LNB are driven. The horizontal and vertical polarization signals are output, respectively. In addition, when the LNB powers VLP _l and VLP ₂ are all 18V, only the first and second interrupt amplifiers 13 and 15 are driven. Accordingly, the first and second output terminals (out _l and out ₂ ) of the LNB are both horizontal. The polarization signal is output.

Here, the reverse pin diodes D ₁ -D ₄ provided at the rear ends of the amplifying transistors Q ₁ -Q ₄ of each of the interrupt amplifiers 13-16 are turned on / off of the respective amplifying transistors Q ₁ -Q ₄ . The isolation characteristic of the is improved through its reverse characteristic.

As described above, the present invention provides a 2 × 2 multi-switch amplification unit inside the LNB device, thereby improving isolation characteristics and minimizing switching insertion loss.

In addition, the present invention can control the polarization selection of the satellite broadcast on the BS tuner set side of the indoor provides convenience for use, and many can receive satellite broadcasts of different polarizations without mutual interference.

Claims (3)

First and second front-end amplifier and the first and second amplifiers with first and second end stops in the double LNB unit comprising an amplifier, a first front-end amplifier (A _l) horizontally polarized signal (Hin) is passed through the first divider ( 11) connected to the first and third sequential amplifiers (l3 and 15), and the vertically polarized signal (Vin) subjected to the second ultra short amplifier (A ₁ ') is passed through the second divider (12). The first and second breaker amplifiers 13 and 14 and the outputs of the third and fourth breaker amplifiers 15 and 16 are common to each other. After the amplification at the termination amplifiers A ₃ and A ₃ ′, the first and second LNB outputs are connected to me, and the driving selection of the _first to fourth termination amplifiers 13-16 is I.NB power (VLP ₁ , VLP _2). Double LNB device characterized in that the connection is determined by the switch voltage generation unit (17) for generating a logic control voltage in accordance with the input. 2. The double LNB apparatus as claimed in claim 1, wherein the first and second dividers (11, 12) are Wilkinson dividers having a 3 dB loss. The circuit isolation of claim 1, wherein the first to fourth interrupt amplifiers 13 to 16 are each configured to turn on / off the polarization input signal amplifying transistors Q _{1 to} Q ₄ and the transistors Q _{1 to} Q ₄ . Double LNB device comprising a reverse pin diode (D ₁ -D ₄ ) for each.