KR20140103221A - Equalizer Circuit Using ATT PAD - Google Patents

Abstract

A high-power broadband optical receiver is disclosed. The high-power broadband optical receiver includes a photoelectric conversion diode (10) which receives an optical signal from an optical signal input terminal (1), converts the optical signal into an RF signal corresponding thereto, and outputs the RF signal; an ultrashort broadband AMP (20) which amplifies the RF signal lowered by photoelectric conversion; a frequency band divider (40) which filters the RF signal amplified by the ultrashort broadband AMP (20) to be divided into a plurality of amplifiable frequency bands; a first frequency band signal processing unit (50) which processes an RF signal of a first frequency band divided by the frequency band divider (40) into a high-power amplified form; a second frequency band signal processing unit (60) which processes an RF signal of a second frequency band divided by the frequency band divider (40) into a high-power amplified form; and a frequency band synthesizer (70) which synthesizes the RF signals respectively processed by the first frequency band signal processing unit (50) and the second frequency band signal processing unit (60) and outputs a synthesized RF signal to an RF output terminal (2).

Description

[0001] Equalizer Circuit Using ATT PAD [0002]

More particularly, the present invention relates to an equalizer circuit using an ATT PAD. More particularly, the present invention relates to an equalizer circuit using an ATT PAD, To an equalizer circuit using an ATT PAD that can compensate for the difference in attenuation of frequencies generated according to the characteristics of a coaxial cable.

In general, in the case of an on-premise transmission amplifier used for amplifying a TV broadcast signal and for increasing the transmission distance and increasing the distribution amount, since the level deviation according to the frequency of the wired broadcasting signal affects the transmission quality of the signal, The ATT PAD and the EQ PAD of the fixed type are used without using the attenuator of the volume type.

The ATT PAD adjusts the amount of attenuation of the signal regardless of the frequency, and the EQ PAD compensates for a portion where the amount of attenuation increases as the frequency of the coaxial cable increases.

In addition, when a conventional transmission amplifier is installed at an installation site, the ATT PAD and the EQ PAD must be held for each loss (1dB to 20dB), and the attenuation and the inclination of the frequency signal vary depending on the installation site ATT PADs and EQ PADs with appropriate losses could be coupled to the on-premise transmit amplifiers for tuning.

However, in case of ATT PAD, since the volume is small and the price is low, the installer can have various ATT PADs for each loss. However, since the EQ PAD has a large volume and high price,

Korean Patent Laid-Open Publication No. 2011-0109016 (October 10, 2011), a line amplifier

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a simple circuit which forms an ATT PAD for attenuating a frequency signal with a set attenuation amount and a high- And to provide an equalizer circuit using an ATT PAD capable of compensating for a difference in attenuation of a frequency generated according to characteristics of a coaxial cable without a circuit configuration of an expensive EQ PAD.

In order to achieve the above object, an equalizer circuit using an ATT PAD according to the present invention includes an ATT PAD for attenuating a frequency signal of all bands included in a cable broadcasting signal input through an input terminal (120); A high frequency path circuit unit (110) selectively passing only a preset high frequency band in the wire broadcast signal; And a cut-off circuit unit 130 for blocking a frequency equal to or greater than a TV signal band in the cable broadcast signal. The ATT PAD 120 and the high-frequency path circuit unit 110 are configured in parallel, The frequency can be attenuated in a form in which the amount of attenuation is reduced and output through the output terminal (OUTPUT).

In addition, the high-frequency path circuit unit 110 can selectively pass only a UHF band high frequency signal that is broadcast-viewable among the frequency signals included in the wired broadcasting signal.

In addition, the cut-off circuit unit 130 can cut off a frequency of 1 GHz or more in the wire broadcast signal.

The high frequency path circuit unit 110 includes a first capacitor C1 connected to an input terminal INPUT for inputting a cable broadcasting signal and a second capacitor C1 connected to the output terminal of the first capacitor C1 and the A third capacitor C3 connected in circuit between the output terminal of the first transformer T1 and the input terminal IN of the ATT PAD 120, The circuit includes a first resistor R1 connected to a circuit line between the first capacitor C1 and the third capacitor C3, an inductor L1 and a second capacitor C2. The cut- Includes a fourth capacitor C4 and a second inductor L2 connected in circuit so as to be connected between the output terminal of the first transformer T1 and the ground terminal GND of the ATT PAD 120, .

According to the equalizer circuit using the ATT PAD according to the present invention, the ATT PAD for attenuating the frequency signal with the set attenuation amount and the high-frequency path circuit portion for passing only the high frequency are connected in parallel to form a circuit, It is possible to replace the function of the EQ PAD to compensate for the difference in the attenuation of the frequency generated according to the present invention.

1 is a block diagram showing a configuration of an equalizer circuit using an ATT PAD according to a preferred embodiment of the present invention.
2 is a circuit diagram showing a circuit configuration of an equalizer circuit using an ATT PAD according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately The present invention should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

The equalizer circuit using the ATT PAD according to the preferred embodiment of the present invention can be realized by a simple circuit that forms an ATT PAD for attenuating a frequency signal with a set amount of attenuation and a high frequency path circuit portion for passing only a high frequency through a circuit, The ATT PAD 120, the high-frequency path circuit unit 110, and the high-frequency path circuit unit 110, as shown in FIGS. 1 and 2, to compensate for the difference in attenuation amount of the coaxial cable depending on the frequency, And a cut-off circuit unit 130.

First, the ATT PAD (Attenuator Pad) 110 attenuates a frequency signal of all bands included in a wired broadcasting signal input through an input terminal INPUT by applying a preset amount of attenuation. A ground terminal GND and an output terminal OUT connected to the high frequency path circuit unit 110 and the cutoff circuit unit 130 as shown in FIG. Can be connected to the circuit through gold-plated pins.

As shown in FIG. 2, the high-frequency path circuit unit 110 includes a circuit (not shown) connected to an input terminal INPUT through which a cable broadcasting signal is input, A first transformer T1 connected in circuit between an output terminal of the first capacitor C1 and each terminal of the ATT PAD 120 and a second transformer T1 connected between the output terminal of the first transformer T1 and the output terminal of the ATT PAD 120. [ A third capacitor C3 connected between the input terminal IN of the second capacitor 120 and a first resistor R1 connected to the circuit line between the first capacitor C1 and the third capacitor C3, An inductor L1 and a second capacitor C2.

The first transformer T1 removes unnecessary noise generated at about 5 MHz or less when the frequency signal of the cable broadcasting band passes through the first capacitor C1. The first transformer T1 is connected to the ATT PAD 120 and the high- And the cut-off circuit unit 130 are connected in parallel to each other.

The first resistor R1, the inductor L1, and the second capacitor C2 are connected to the third capacitor C3 at a highest point to which the third capacitor C3 is to pass through the high frequency, Loss, and so on.

The cut-off circuit unit 130 is connected in parallel to the ATT PAD 120 in parallel with the high-frequency path circuit unit 110 as shown in FIG. 2, A fourth capacitor C4 and a second inductor L2 connected in circuit so as to be connected between the output terminal of the first transformer T1 and the ground terminal GND of the ATT PAD 120, . Here, since the fourth capacitor C4 and the second inductor L2 are connected in parallel to the circuit and connected to GND, a frequency band higher than the frequency corresponding to the set L value and C value is blocked through the GND.

Meanwhile, the high-frequency path circuit unit 110 selectively passes only the UHF band high-frequency signals that are broadcast-viewable among the frequency signals included in the cable broadcasting signal, and the cut-off circuit unit 130 passes through the high- Frequency signal having a larger magnitude than that of the largest one of the high-frequency signals. Generally, since the broadcast channel of the UHF among the cable broadcasting channels has a frequency size ranging from the channel 66 (frequency of 470 MHz or more) to the channel 135 (frequency of 1,002 MHz), the frequency band of 1 GHz or more As shown in FIG.

Meanwhile, as shown in the figure, the ATT PAD 120 and the high-frequency path circuit unit 110 are configured in a parallel form to gradually attenuate the attenuation amount so that the amount of attenuation decreases from a low frequency to a high frequency, And a wired broadcasting signal in which a high-frequency signal passes through is output as an output terminal (OUTPUT).

For example, when the high frequency band set in the high frequency path circuit unit 110 is 5 MHz to 1 GHz and the attenuation amount set in the ATT PAD 120 is 5 dB, the attenuation is reduced to about 5 dB at a frequency of 5 MHz, As the frequency size increases, the amount of attenuation gradually decreases, and when attaining the frequency of 1 GHz, attenuation is applied to 0 dB.

That is, if only the ATT PAD 120 is provided without the circuit configuration of the high frequency path circuit unit 110, the ATT PAD 120 is output in the form of attenuation by 5 dB in all the frequency bands corresponding to 5 MHz to 1 GHz. And the high frequency path circuit unit 110 are configured in a parallel form, it is possible to compensate the portion where the attenuation amount increases as the frequency, which is the characteristic of the coaxial cable, increases.

According to the configuration and function of the equalizer circuit using the ATT PAD according to the preferred embodiment of the present invention, the ATT PAD 120 for attenuating the frequency signal with a predetermined amount of attenuation and the high- 110) can be replaced with a conventional EQ PAD function that compensates for the difference in attenuation of the coaxial cable depending on the frequency by using only a simple circuit constituting a parallel circuit. Thus, the installation process of the transmission amplifier in the room becomes easy, It is possible to realize a reduction effect.

In addition, the equalizer circuit itself using the ATT PAD is designed so as to be compatible with the ATT PAD held in the existing cable broadcasting company, so that the ATT PAD of the existing transmission amplifier can be replaced and connected to the circuit.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It is to be understood that various modifications and changes may be made without departing from the scope of the appended claims.

110 ... high frequency path circuit part 120 ... ATT PAD
130 ... cut-off circuit

Claims (4)

An ATT PAD 120 for attenuating a frequency signal of all bands included in a wire broadcast signal input through an input terminal by applying a preset attenuation amount;
A high frequency path circuit unit (110) selectively passing only a preset high frequency band in the wire broadcast signal; And
And a cut-off circuit unit (130) for blocking a frequency of the TV signal band or more from the wired broadcasting signal,
The ATT PAD 120 and the high-frequency path circuit 110 are connected in parallel to each other. The ATT PAD 120 and the high-frequency path circuit 110 are connected in parallel to each other. The ATT PAD 120 and the high- .
The method according to claim 1,
Wherein the high frequency path circuit unit (110) selectively passes only a high frequency signal of a UHF band that is broadcast-viewable among the frequency signals included in the wire broadcast signal.
3. The method of claim 2,
The cut-off circuit unit (130) cuts off a frequency of 1 GHz or more in the wire broadcast signal.
The method of claim 3,
The high frequency path circuit unit 110 includes a first capacitor C1 connected to an input terminal INPUT for receiving a wire broadcast signal and a second capacitor C1 connected between the output terminal of the first capacitor C1 and each terminal of the ATT PAD 120. [ A third capacitor C3 connected between the output terminal of the first transformer T1 and the input terminal IN of the ATT PAD 120 through a circuit connected to the first capacitor T1, A first resistor R1 connected to a circuit line between the first capacitor C1 and the third capacitor C3, an inductor L1 and a second capacitor C2,
The cut-off circuit unit 130 includes a fourth capacitor C4 and a second inductor L2 connected in parallel so as to be connected between the output terminal of the first transformer T1 and the ground terminal GND of the ATT PAD 120, Wherein the at least one equalizer circuit comprises an ATT PAD.

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