KR20020068122A - Method for dissipating emi and static electricity of very high bit rate modem for asymmetric digital subscriber line - Google Patents

Abstract

PURPOSE: A method for dissipating EMI and static electricity of very high bit rate modem for ADSL(Asymmetric Digital Subscriber Line) is provided to protect a product from an electromagnetic wave and an electrostatic wave by preparing an MOV(Metal Oxide Varistor) and a feed-through capacitor between a line driver and a telephone line. CONSTITUTION: A PCI(Peripheral Component Interconnect) bus interface(10) exchanges data with a computer. An ADSL DMT(Discrete Multi Tone) data pump(20) performs a DSP(Digital Signal Process) for a DMT ADSL transport in an ADSL modem. A line driver(30) performs an ADSL transmitting/receiving. An analog front end(40) interfaces an analog signal of the line driver(30) with a digital signal of the ADSL DMT data pump(20). An MOV and a feed-through capacitor are prepared between the line driver(30) and a telephone line to reinforce a ground pattern.

Description

Electromagnetic and static electricity treatment method of high speed modem for asymmetric digital subscriber transmission line {METHOD FOR DISSIPATING EMI AND STATIC ELECTRICITY OF VERY HIGH BIT RATE MODEM FOR ASYMMETRIC DIGITAL SUBSCRIBER LINE}

The present invention relates to a method for processing electromagnetic waves and static electricity of a high speed modem for an asymmetric digital subscriber transmission line. More particularly, the present invention relates to an electromagnetic wave of a high speed modem for an asymmetric digital subscriber transmission line for protecting a product from electromagnetic waves and static electricity and preventing malfunction. And an electrostatic treatment method.

Recently, beyond the existing simple analog voice service, high-quality voice service, high-speed data transmission service, VOD, video conferencing service, etc. by using a lower-cost service other than the expensive T1 line which has been obstructing the existing high-speed communication. Is asking.

Subscriber lines installed in many subscriber premises or small businesses are copper two-wire telephone networks. The existing modem using this technology converts the subscriber's data signal into analog form and transmits it through the Plain Old Telephone Service (POTS) line, which guarantees a transmission speed of up to 56Kbps thanks to the development of modulation and compression technology. However, multimedia applications that are currently in the spotlight in many computer networks have a problem that cannot be used at 56 Kbps.

In addition, one way to provide a broadband service such as multimedia to meet the needs of the subscriber is to build an optical cable network to the subscriber's home. However, it will take a long time for such a broadband cable to be provided to all subscribers, and there is a problem that the realization is long since a huge cost must be invested.

At present, the use of copper cable that is configured to the subscriber's house uses only a fraction of its transmission capacity, that is, 3.4 중 of 1 MHz. Therefore, it is sufficient to accommodate a multimedia service when using the maximum transmission capacity, a technology that enables high-speed data communication using such a copper wire (Asymmetric Digital Subscriber Line (hereinafter referred to as ADSL)).

ADSL modem is a technology that provides high speed downstream channel from network to subscriber and low speed up data channel from subscriber to network using existing two-wire telephone network, and at the same time, provides existing voice service. ADSL supports 1.5Mbps to 8Mbps downlink from subscriber to subscriber and 16Kbps up to 1Mbps from subscriber to telephone station, although it varies according to transmission distance and equipment. ADSL is a high speed and asymmetrical feature of its transmission speed that provides continuous solutions for telephone operators, Internet operators and value-added service providers by providing useful solutions for subscribers and small businesses in film, telephone, video catalog, LAN access, VOD and high speed internet access. It is expected to serve the market.

1 is a configuration diagram showing an example of unidirectional communication using a TP (twist pair) two-wire system in the ADSL method.

Existing telephone modems utilize the functions and characteristics of telephone line and telephone network (PSTN) as they are, instead of converting digital signals to analog signals as voice signals instead of telephone voice. However, ADSL technology, as shown in Fig. 1, connects an ADSL modem to both ends of a telephone line, that is, a subscriber side and a telephone station, to form a communication channel having a frequency band different from that of a telephone signal, and through this channel, Send and receive data.

In this case, a typical analog voice band modem uses the 0-4 kHz frequency band as a telephone service, and therefore voice and data cannot be used simultaneously. However, the ADSL modem operates at a different frequency band from voice, that is, 100 kHz to 1.1 MHz, so that the existing telephone service and the ADSL data service can be used simultaneously. In addition, voice telephone service continues even when the ADSL equipment is down.

Meanwhile, an echo cancellation technique and an automatic equalization technique are used as transmission techniques of an ADSL modem. The echo cancellation technique is used when two transmission / reception signals using the same bandwidth are to be communicated through one transmission line. The main causes of the reflection include mismatch between hybrid impedance and line impedance, bridge tap, connection of heterocores, and the like. Therefore, the echo canceller included in the ADSL modem removes the echo component by estimating the transfer function of the path where the transmission signal component leaks when the transmission signal is leaked to the receiver and mixed with the reception signal.

In addition, the automatic equalization technique is subjected to amplitude and phase distortion while the signal is transmitted through the communication path and is used to compensate for this distorted signal. Recently, with the development of digital signal processing technology can be processed in the digital domain, such as LE (Line Equalizer) or Decision Feedback Equalizer (DFE) is used. These equalizers use a digital filter of the FIR type and the coefficient of the filter is automatically adjusted according to the condition of the line.

The ADSL modem as described above is a card type PCI system embedded in a personal computer (PC), which is driven by a 5V power supply of a computer, and is connected to a dedicated circuit through a 4-terminal connector to transmit and receive data at 1Mbps.

However, in the ADSL modem according to the prior art as described above, various electromagnetic waves and static electricity are generated, resulting in various problems such as product damage or malfunction.

The present invention has been made to solve the problems of the prior art as described above, the object is to connect the metal oxide varistor (MOV) and the bead through capacitor between the line driver and the telephone network, and by reinforcing the ground pattern and electromagnetic wave and The present invention provides a method for processing electromagnetic waves and static electricity of a high speed modem for an asymmetric digital subscriber transmission line to protect from static electricity.

1 is a block diagram showing an example of unidirectional communication using a TP (twist pair) two-wire in the ADSL method

2 is a block diagram schematically showing the configuration of an ADSL modem to which the present invention is applied.

<Description of Symbols for Main Parts of Drawings>

10: Bus Bus (PCI Bus Interface)

20: ADSL DMT Data Pump

30: Line Driver

40: Analog Front End

According to a feature of the present invention for achieving the above object, a bus interface (PCI Bus Interface) connected to the computer to exchange data, and a digital signal for DMT ADSL transmission in an asymmetric Digital Subscriber Transmission Line (ADSL) modem An ADSL DMT Data Pump that performs DSP, a Line Driver that performs ADSL transmission and reception (Tx / Rx) connected to a telephone network, and is connected between the data pump and the line driver. A method for processing electromagnetic waves and static electricity, which is applied to a high speed modem for an asymmetric digital subscriber transmission line including an analog front end for interfacing a digital signal of the data pump and an analog signal of the line driver.

Electromagnetic and static electricity of a high speed modem for an asymmetric digital subscriber transmission line connecting a metal oxide varistor (MOV) and a bead through capacitor between the line driver and the telephone network, and reinforcing a ground pattern to protect from electromagnetic waves and static electricity. Provide a treatment method.

The above objects and various advantages of the present invention will become more apparent from the preferred embodiments of the invention described below with reference to the accompanying drawings by those skilled in the art.

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

2 is a block diagram showing the configuration of an ADSL modem to which the present invention is applied.

Referring to FIG. 2, reference numeral 10 denotes a bus interface connected to a host-based ADSL controller software for transmitting and receiving data, and 20 denotes a DMT ADSL in an ADSL modem. An ADSL DMT Data Pump, which performs digital signal processing (DSP) for transmission, represents a line driver 30 that is connected to a telephone line and performs ADSL transmission / reception (Tx / Rx). 40 is an analog front end connected between the data pump 20 and the line driver 30 to interface a digital signal of the data pump 20 with an analog signal of the line driver 30. Indicates.

At this time, in the present invention, in order to protect the product from electromagnetic waves and static electricity and to prevent malfunctions, a metal oxide varistor (MOV) and a bead through capacitor are connected between the line driver 30 and the telephone line, and the ground pattern Reinforced.

While the invention has been shown and described in connection with specific embodiments thereof, it is well known in the art that various modifications and changes can be made without departing from the spirit and scope of the invention as indicated by the claims. Anyone who owns it can easily find out.

As described above, according to the electromagnetic wave and static electricity processing method of the high speed modem for asymmetric digital subscriber transmission line of the present invention, a metal oxide varistor (MOV) and a bead through capacitor are connected between the line driver and the telephone network, and the ground pattern is reinforced. As a result, the product can be protected from electromagnetic waves and static electricity.

Claims (1)

Bus interface (PCI Bus Interface) connected to a computer to exchange data, and an ADSL DMT Data Pump to perform digital signal processing (DSP) for DMT ADSL transmission inside an asymmetric Digital Subscriber Transmission Line (ADSL) modem And a line driver connected to a telephone network to perform ADSL transmission / reception (Tx / Rx), and connected between the data pump and the line driver to interface a digital signal of the data pump and an analog signal of the line driver. In the method for processing electromagnetic waves and static electricity applied to a high speed modem for an asymmetric digital subscriber transmission line comprising an analog front end (Analog Front End), Electromagnetic and static electricity of a high speed modem for an asymmetric digital subscriber transmission line connecting a metal oxide varistor (MOV) and a bead through capacitor between the line driver and the telephone network, and reinforcing a ground pattern to protect from electromagnetic waves and static electricity. Treatment method.