JP2003179454A - Splitter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a splitter capable of surely realizing high speed in signal transmission by using an ADSL (asymmetric digital subscriber line) system. <P>SOLUTION: The splitter 10 for dividing a signal transmitted by an ADSL system via a pair of transmission lines into an ADSL signal and a sound signal to output the signals is provided with a low-pass filter 20 for outputting the sound signal, and a common mode filter 30 connected in parallel with the filter 20 for outputting the ADSL signal. Since the filter 30 has a high impedance with respect to a signal transmitted in phase through the transmission lines, the noise components in the ADSL signal are cancelled and the signal from which the noise components are eliminated can be outputted. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a splitter device for distributing a telephone voice signal (low frequency signal) and a data communication ADSL signal (high frequency signal) in signal transmission by a broadband system, and more particularly,
The present invention relates to a structure of a splitter device that prevents a decrease in communication speed when performing data communication.

[0002]

2. Description of the Related Art In recent years, signal transmission by a broadband method using a conventional telephone line such as ADSL has been rapidly spread. The ADSL method is inexpensive because it uses a telephone line, and has the advantage that the transmission and reception of data signals can be speeded up by making the transmission path regions in the transmission and reception directions asymmetric.

AD using a line consisting of a pair of transmission lines
In the case of signal transmission by the SL system, between the line (input) side and the device (output) side (telephone or personal computer), a voice signal for telephone transmission via the line and A for data communication
It is necessary to interpose a splitter device for distributing the DSL signal.

Conventionally, this splitter device has a low-pass filter 20 for outputting a voice signal (telephone signal) by outputting only low-frequency components of signals input from the lines 1 and 2 as shown in FIG. , Signal lines 1 ', 2 that directly output signals input from the line side as they are
'And are composed.

[0005]

However, according to the distribution of the carrier wave by the broadband method using the above-mentioned splitter device, there is a case that the speed-up which is an advantage of the ADSL method cannot be achieved as expected. This is because the signal transmitted on the line is directly output as a signal on the device side, so the signal waveform is deformed due to interference with the ISDN line, and noise from the data service device using the line is superimposed on the high frequency signal. It is thought that this is due to a matter.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a splitter device which can surely realize high speed in signal transmission by the ADSL system.

[0007]

To achieve the above object, the invention of claim 1 is a splitter for distributing a signal distributed by the ADSL system via a pair of transmission lines into an ADSL signal and a voice signal and outputting the signal. The device is characterized by including the following configuration. The splitter device includes a low-pass filter for outputting the audio signal,
It comprises a common mode filter connected in parallel to the low pass filter for outputting a DSL signal.

A second aspect of the present invention is the splitter apparatus according to the first aspect, which comprises a pair of primary ends and a pair of secondary ends.
It is characterized by comprising a common mode choke coil in which the primary end is connected to the input side and the secondary end is connected to the output side.

According to a third aspect of the invention, in the splitter apparatus according to the first aspect, a surge arrester is connected between the transmission lines on the input side of the low-pass filter and the common mode filter.

According to the present invention, the common mode choke coil is interposed between the ADSL signals input from the pair of transmission lines, so that a high impedance can be obtained for signals flowing in the same phase through the transmission lines. ADS
It is possible to cancel the noise component in the L signal and output a signal from which the noise component has been removed.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A splitter device as an example of an embodiment of the present invention will be described with reference to the circuit diagram of FIG. The splitter device 10 converts a signal distributed by the ADSL method through a pair of transmission lines 1 and 2 forming a line into an audio signal (low frequency signal) and an ADSL signal (high frequency signal).
And a low frequency signal distribution circuit 20
And the high frequency signal distribution circuit 30 are connected in parallel to the input side.

The low-frequency signal distribution circuit 20 has two lines in which two coils 21 and 22 are connected in series, and the coil connection midpoints in each line are connected via a capacitor 23. It is composed of a low-pass filter composed of a circuit in which one side of the line is a transmission line (signal line 1, 2) side and the other side is a connection side to the telephone 3. With this low-pass filter, a high-frequency signal can be removed from a signal distributed by the ASDL system via a pair of signal lines 1 and 2 on the line side, and only an audio signal (low-frequency signal) can be taken out to the output side. .

The high-frequency signal distribution circuit 30 includes a pair of magnetically coupled coils 31 and 32 having terminals on one side of each coil on the line (signal lines 1 and 2) side and the other side on the equipment side such as a personal computer 4. It is composed of a common mode filter composed of the circuit. More specifically, the common-mode filter is composed of a set of inductors wound around a single core in a bifilar, and the winding start side end of each inductor is connected to the input (line) side, and the winding end The side end is composed of a common mode choke coil connected to the output (device) side.

Each inductor constituting the common mode choke coil has a high impedance to the extent that common mode noise supplied from the line side is prevented from propagating to the device side. Therefore, with this circuit configuration, the signal from which the noise component has been removed is output with respect to the ADSL signal propagated from the input side.

A surge arrester 11 is connected between the input side of the low-pass filter 20 and the common mode filter 30, that is, between the input side lines (the signal line 1 and the signal line 2) of the split device 10. The surge arrester 11 is for preventing a high voltage from being applied to the low-pass filter 20 and the noise canceling circuit 30 when a lightning strike occurs and destroying the device. Further, by connecting the surge arrester 11 to the input sides of the low pass filter 20 and the common mode filter 30, both the low pass filter 20 and the common mode filter 3 can be protected by one surge arrester.

According to the above configuration, since the common mode choke for preventing the propagation of the noise component is connected to the ADSL signal input from the pair of transmission lines on the line side, the noise component is removed. Since the ASDL signal is output to the personal computer side, it is possible to cancel the signal waveform deformation due to the interference with the ISDN line and the noise from the data service equipment using the telephone line, and ensure the speedup which is the advantage of the ASDL system. Can be realized.

Since the surge arrester 11 is connected to the input side of the splitter device 10, the low pass filter 20
It is possible to prevent a high voltage from being applied to the common mode filter 30 and to prevent the device from being damaged when lightning occurs.

[0018]

According to the splitter device of the present invention, since the common mode filter for canceling the noise component is connected to the ASDL signal input from the pair of transmission lines, the ADSL signal from which the noise component is removed is output. Since the data can be output, noise in the ADSL signal for data communication can be removed, and speedup, which is an advantage of the ADSL system, can be surely realized.

[Brief description of drawings]

FIG. 1 is a circuit diagram for explaining a configuration of a splitter device of the present invention.

FIG. 2 is a circuit diagram for explaining the configuration of a conventional splitter device.

[Explanation of symbols]

1, 2 ... Signal line (line), 3 ... Telephone, 4 ... Equipment (PC), 10 ... Splitter device, 11 ... Surge arrester, 20 ... Low-frequency signal distribution circuit (low-pass filter), 30 ... High frequency signal distribution circuit (common mode filter)

Claims (3)

[Claims] 1. A splitter device for distributing a signal distributed by an ADSL system via a pair of transmission lines into an ADSL signal and a voice signal and outputting the split signal, wherein the splitter device outputs the voice signal. And a common mode filter connected in parallel to the low-pass filter for outputting the ADSL signal. 2. The common mode filter comprises a pair of primary ends and a pair of secondary ends, and a common mode choke coil having the primary end connected to the input side and the secondary end connected to the output side. The splitter device according to claim 1. 3. The splitter device according to claim 1, wherein a surge arrester is connected between the transmission lines on the input side of the low-pass filter and the common mode filter.