KR200156086Y1 - A directional coupler including an upward noise blocking module - Google Patents

Abstract

The present invention relates to a branching apparatus having an uplink noise band suppression module installed in a branching unit to prevent an uplink noise in a predetermined frequency range, and having an uplink noise suppression function of the entire transmission path. In a branching apparatus provided at the subscriber side and having an input terminal to which a signal transmitted from a CATV operator side is input and a plurality of branch output terminals for performing branching of the input signal, each end of each of the branch output terminals is grounded. A high pass filter comprised of two or more inductors and one or more capacitors disposed between the inductors, for preventing upward noise that may be generated on the subscriber side; And a jumper connected to both ends of the capacitor to bypass the high pass filter when using a bidirectional supplementary service, and separated from both ends of the capacitor to exhibit characteristics of the high pass filter when not using a bidirectional supplementary service. It characterized in that it comprises a selective upward noise suppression module consisting of. According to the present invention, the uplink noise suppression module is simply incorporated into an existing tap-off so that the uplink noise generated from the subscribers not using the bidirectional supplementary service can be effectively prevented by simply connecting or disconnecting the jumpers in the module according to the subscriber's needs. As a result, the subscriber using the bidirectional supplementary service can be provided with a high quality supplementary service.

Description

Tap-offs with Upward Noise Rejection Module

The present invention relates to a branching device installed at a subscriber side on a CATV transmission path to perform signal branching, and in particular, an upband suppression module is installed in the branching branch to prevent upward noise in a predetermined frequency range. A diverter with an uplink noise suppression module to block noise.

In the two-way CATV system currently in use, subscribers are not only unilaterally provided TV broadcasting programs or CATV broadcasting programs from CATV broadcasting companies, but also security, disaster prevention, Two-way additional services such as home banking, home shopping, PC communication, and Internet communication are provided.

In general, in a unidirectional or bidirectional CATV system, a branching unit such as a branching unit, a branching branch, an branching branch, or the like is installed on the subscriber side. It is attenuated by the size and delivered to the subscriber equipment.

By the way, when a subscriber who subscribes to the bidirectional supplementary service uses the service, from the subscriber's house which does not use the bidirectional supplementary service, for example, from various electronic devices such as a heating apparatus or a PC, or for some reason, It is easy to introduce unwanted noise in the desired frequency range, for example in the range of 0 (direct current) to 42 MHz, ie upward noise, from the point to the head end installed on the CATV broadcaster or other service provider side.

If a large amount of upstream noise is introduced into the uplink band used for the bidirectional supplementary service above the appropriate value (depending on the equipment supporting the supplementary service), a signal transmitted in the band is physically supported to support the supplementary service. If the uplink noise is light, the service may be impaired, and in some cases, the service itself may have to be abandoned.

In such a situation, in the case of the conventional tap-changer, a means for preventing upward noise introduced on the CATV line from the noise source in the subscriber's house which does not use the bidirectional supplementary service is constituted in the tap-off or the CATV transmission path. The lack of installation on the equipment itself has resulted in a loss of time and manpower to keep the upward noise below a reasonable level, thereby facilitating aging changes in the transmission path.

In order to prevent this, conventionally, the use of materials with better characteristics in transmission line construction or the use of advanced technicians to supervise the construction more thoroughly to complete the construction, especially the subscriber line with high up noise. Only a separate up-noise noise filter module is attached. Therefore, it is difficult to provide high quality services to users using the uplink additional services.

Therefore, in order to solve such a problem in the prior art, the present invention is to provide an uplink noise suppression module that can be selectively used inside the branch is basically installed on the CATV transmission path.

In order to achieve the above object, the branching device according to the present invention is installed on the subscriber side on the CATV transmission path, the input terminal to which the signal transmitted from the CATV business vehicle side is input and a plurality of branch output stages for performing output of the branched input signal In the splitter provided with each of the plurality of branch output stages, each of the plurality of branch output stages is composed of two or more inductors, each of which is grounded and one or more capacitors disposed between these inductors, upwardly flowing from the subscriber side A high pass filter to block noise; And an optional upstream noise rejection module connected to both ends of the capacitor, the jumper configured to bypass the high pass filter.

1 is a quarter-circuit circuit diagram equipped with a selective upward noise suppression module according to the present invention.

* Explanation of symbols for main parts of the drawings

1: input 2: output

3: branch output stage 4: jumper

5: upward noise suppression module C1 to C3: capacitor

L1 ~ L3: Inductor T1 ~ T5: Transformer

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

FIG. 1 is a schematic circuit diagram of a quarter-branch having an up-noise noise suppression function in which an up-noise noise suppression module represented by a dotted block in a conventional tap-off is mounted.

First, the general configuration of the tap-off and its operation will be briefly described.

As shown in FIG. 1, the tap-changer generally includes an input stage 1 for inputting a signal transmitted from a CATV broadcaster or other service provider side, an inductor L1 and 2 connected to the input stage 1; Signal separation means consisting of two capacitors (C1, C2), an output terminal (2) connected to the inductor (1) and a capacitor (C2), a plurality of transformers (T1 to T5), and a plurality of branch output terminals connected to a subscriber's house (3) and the like.

In this configuration, the inductor L1 of the separating means bypasses the DC component among the signal components flowing into the input terminal 1, and the two capacitors C1 and C2 allow the DC component to flow into the branch output terminal 3. It prevents the high frequency components to flow into the branch output stage (3) while preventing. That is, the inductor L1 and the capacitors C1 and C2 serve to separate the DC component and the high frequency component from the signal introduced from the input terminal 1. The transformer T1 prevents a signal coming into the input terminal 1 toward the output terminal 2 from being directed toward the branch output terminal 2 and prevents a signal coming from the branch output terminal 3 from exiting the output terminal 2. In addition, the winding side of the transformer T3 coupled to the resistor R2 prevents a signal coming from one branch output terminal 3 from going to the other branch output terminal 3. The other winding of the transformer T3 and the transformer T2 perform impedance matching to improve the Q of the circuit. Transformers T4 and T5 function to convert signal voltages.

In the above-described configuration, it is difficult to provide high quality service to a subscriber using the supplementary service because the uplink noise generated from the subscriber not using the supplementary supplementary service is likely to flow into the transmission path of the subscriber using the supplementary supplementary service. Has already been described above.

In view of this, the present invention aims to provide an uplink noise canceling module 5 that can effectively block uplink noise generated from a subscriber who does not use a bidirectional supplementary service.

The uplink noise suppression module according to the present invention is a block for blocking upstream noise of 0 (direct current) to 42 MHz from a subscriber not using a bidirectional supplementary service to each of the multiple branch output stages 3 of the above-described brancher. (Cutoff) Includes a kind of highpass filter with a frequency of 42 MHz.

This high pass filter, as shown in FIG. 1, illustratively consists of two inductors L2 and L3 having one end grounded and a capacitor C3 disposed between these inductors L2 and L3. Consists of. However, the present invention is not limited thereto, and the filter configuration may be changed in various ways to improve the characteristics of the filter. For example, it may be possible to provide two or more inductors and one or more capacitors.

In addition, a jumper 4 is additionally installed in the upward noise suppression module of the present invention. As the material of the jumper 4, it is preferable to use an iron wire or a copper wire plated with a gold plating or a material having electrical conductivity equivalent thereto. However, the jumper 4 is not necessarily limited thereto and may be a conductive material.

As shown in FIG. 1, this jumper 4 is arranged to allow the subscriber to attach or remove it arbitrarily across the capacitor C3 of the high pass filter 5. The jumper 4 is connected to both ends of the capacitor to bypass the high pass filter when the subscriber uses the bidirectional supplementary service, and to display the characteristics of the high pass filter when the bidirectional supplementary service is not used. It is intended to be separated from both ends of the capacitor.

As such, the uplink noise suppression module 5 of the present invention, which is composed of the high pass filters C3, L2, and L3 and the jumper 4, is mounted to each branch output stage 3, respectively. If the subscriber connected to the branch output does not use the supplementary service, do not connect the jumper shown in the dashed block shown in FIG. 1, and connect the jumper only when using the supplementary service to bypass the ascending noise suppression module. To help.

One jumper is provided for each upward noise rejection module, allowing independent installation and removal regardless of the status of the other branch output terminals.

Until now, the uplink noise suppression module according to the present invention has been described using the fourth quarter as illustrated in FIG. 1, but the module is applicable to the second quarter, the eighth quarter, as well as the fourth quarter. Of course it is possible.

As will be apparent from the description of the present invention up to now, by simply embedding the uplink noise suppression module according to the present invention into the existing branch, simply do not use the bidirectional supplementary service by simply connecting or disconnecting the jumpers in the module according to the needs of the subscriber. Since upstream noise generated from subscribers that do not exist can be effectively prevented, a subscriber using a bidirectional supplementary service can be provided with a high quality supplementary service.

Claims (1)

In the splitter provided on the subscriber side on the CATV transmission path and provided with an input terminal for inputting a signal transmitted from the CATV operator side and a plurality of branch output terminals for performing branching of the input signal and outputting each of the plurality of branch output terminals. A high pass filter comprising two or more inductors each grounded at one end and one or more capacitors disposed between these inductors to prevent upward noise from the subscriber side; And an optional upward noise rejection module connected to both ends of said capacitor, said jumper adapted to bypass said high pass filter.