KR20130042086A

KR20130042086A - Method for simultaneously transfering analog signal and digital signal on plc

Info

Publication number: KR20130042086A
Application number: KR1020110106173A
Authority: KR
Inventors: 정의성
Original assignee: 주식회사 셈앤텍
Priority date: 2011-10-18
Filing date: 2011-10-18
Publication date: 2013-04-26

Abstract

PURPOSE: A method for simultaneously transferring an analog signal and a digital signal in a PCL(Power Line Communication) is provided to modulate each of analog signals and digital signals to a different frequency band, and transfer the modulated signals simultaneously to an external terminal though one telecommunication line. CONSTITUTION: A method for simultaneously transferring an analog signal and a digital signal comprises of: generating a low frequency by low frequency modulation of an analog monitoring image, and sending the generated low frequency to pass though a low-pass filter (S110,S120); generating a high frequency by high frequency modulation of a digital signal, and sending the generated high frequency to pass though a high-pass filter (S130,S140); generating a transmission signal for each frequency band not to overlay to the other for transferring the low frequency and high frequency though one telecommunication line. [Reference numerals] (AA) Start; (BB) End; (S110) Generating a low frequency communication signal; (S120) Passing through a low-pass filter; (S130) Generating a high frequency communication signal; (S140) Passing through a high-pass filter; (S150) Generating a transmission signal;

Description

Method for simultaneously transferring analog signal and digital signal on PLC in PLC communication

The present invention relates to power line communication, and more particularly, to a method for simultaneously transmitting analog and digital signals through a single communication line in a power line communication method in a communication line such as a public telephone line or a coaxial cable.

Power line communication (PLC) refers to a communication method of transmitting and receiving data signals through a power line wired for power supply to a home or an office. That is, power line communication may be implemented by modulating and transmitting a data signal to an AC line as a high frequency signal and separately receiving the signal using a high frequency filter having a 50 Hz or 60 Hz cutoff frequency.

If you plug the power cord into the socket of your home or office, it is a communication service that can use voice, data, Internet, etc. at high speed. It is a communication technology that can connect to all home information devices such as TV, telephone, personal computer. When this technology is realized, data transmission paths that have been complicated with wired television networks, telephone lines, and optical networks will be reduced to one power line. Therefore, the power line communication technology has a merit that there is no burden of additional wiring work because the network can be constructed by using existing wiring, and even after the network is established, additional equipment can be plugged into the network only by plugging in. The added scalability ensures widespread adoption in wired and wireless network solutions.

Conventionally, a communication line used for power line communication is widely used as a public telephone line, a power line or a coaxial cable. 1 is a functional block diagram illustrating a method of transmitting data in a power line communication system having a terminal for transmitting a plurality of analog signals and a terminal for transmitting a digital signal.

Referring to Figure 1, the analog terminal 1 (11) for generating and transmitting an analog signal, for example, analog closed-circuit television (hereinafter referred to as an analog CCTV), the analog image of the image capture and the image is modulated demodulation The unit 21 is modulated to the first analog signal and transmitted to the wired / wireless network 40 through the communication line 31 to which the terminal 1 is connected. The first analog signal is transmitted to an external terminal 50, for example a supervisor terminal, via the wired / wireless network 40.

On the other hand, the digital terminal 2 (13) that generates and transmits a digital signal, for example, an IP camera, photographs a digital image, and the captured image is modulated by the modulation and demodulation unit 23 into a second analog signal so that the terminal 2 is connected. It is transmitted to the wired / wireless network 40 through the communication line 33. The second analog signal is transmitted to the external terminal 50 via the wired / wireless network 40.

However, referring to the conventional power communication system described above, terminals to transmit signals are connected to a dedicated communication line assigned to each terminal, and transmit data generated through the dedicated communication line to an external terminal. Therefore, it is inconvenient to install a separate dedicated communication line for each terminal.

The present invention is to overcome the inconvenience of the conventional power communication system, the object of the present invention is to modulate the analog signal and the digital signal in different frequency bands, and then simultaneously transmitted to the external terminal through one communication line It is to provide a way to.

In order to achieve the object of the present invention, a method for simultaneously transmitting an analog signal and a digital signal according to the present invention comprises the steps of low-frequency modulating the analog surveillance image to generate a low-band communication signal and passing the generated low-band communication signal to the low-frequency filter and And generating a high frequency band communication signal by high frequency modulating the digital signal and passing the generated high frequency communication signal through a high frequency filter, and transmitting the low band signal and the high band signal so that frequency bands do not overlap each other on the same communication line. Generating and transmitting.

The analog surveillance image is modulated into a low band communication signal having a frequency of 0 to 6 Hz, and the digital signal is modulated into a high band communication signal having a frequency of 6 to 32 Hz.

Simultaneous transmission method of an analog signal and a digital signal according to the present invention has various effects as follows.

First, the analog signal and digital signal transmission method according to the present invention by transmitting the analog signal and the digital signal at the same time through one communication line, there is no need for a dedicated communication line corresponding to each terminal.

Second, the simultaneous transmission method of the analog signal and the digital signal according to the present invention modulates the analog signal into a low frequency signal, modulates the digital signal into a high frequency signal and low frequency filtering and high frequency filtering of the analog signal and the low frequency signal, respectively, Even if one transmission signal is generated from the high band signal, communication quality can be prevented from deteriorating.

1 is a functional block diagram illustrating a communication line automatic selection system according to the present invention.
2 is a flowchart illustrating a communication line automatic selection method according to an embodiment of the present invention.
3 is a flowchart illustrating a method for automatically selecting a communication line according to another exemplary embodiment of the present invention.

Hereinafter, a method for automatically selecting a communication line according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a functional block diagram illustrating a simultaneous transmission system of an analog signal and a digital signal according to the present invention.

Referring to FIG. 1, the terminal 1 110 and the terminal 2 120 are connected to a wired / wireless network 400 through one communication line 300 for performing power line communication. Here, a public telephone line, a coaxial cable, a power line, or the like may be used as the communication line, and various communication lines capable of performing power line communication may be used according to the field to which the present invention is applied.

Terminal 1 110 refers to a terminal for generating analog data, such as analog CCTV, for example, terminal 2 (120) refers to a terminal for generating digital data, such as IP cameras, the Internet, for example. it means. The data generated by the terminal 1 110 is low-frequency modulated by the modulator 1 210 to be modulated into a low-frequency first analog signal, and the data generated by the terminal 2 120 is modulated by the high-frequency demodulator 2 220. And is modulated into a second high-bandwidth analog signal. Here, the modulator 1 210 modulates the data generated by the terminal 1 110 into a low band signal of 0 to 6 Hz, and the modulator 2 220 modulates the data generated by the terminal 2 120 from 6 to 6 Hz. Modulate to a high frequency signal of 32 Hz.

The simultaneous transmission unit 300 includes a low frequency filter unit 310, a high frequency filter unit 320, and a transmission signal generator 330. The low frequency filter unit 310 filters the modulated first analog signal to reduce the low frequency. Passing only the low band signal and removing signals other than the low band signal, the high frequency filter unit 320 filters the modulated second analog signal to pass only the high frequency signal of high frequency and removes signals other than the high band signal. The transmission signal generator 330 generates the transmission signal including both the first analog signal and the second analog signal by adding the filtered low band signal and the high band signal so that the first analog signal and the second analog signal do not overlap each other. do. The transmission signal generator 330 transmits the generated transmission signal to the external terminal 500 through the wired / wireless network 400.

3 is a flowchart illustrating a simultaneous transmission method of an analog signal and a digital signal according to an embodiment of the present invention.

Referring to FIG. 3, a first analog signal is generated by modulating data input from a terminal generating analog data into a low band signal having a low frequency of 0 to 6 Hz (S110). The analog signal passes through the low frequency filter and filters except the signal except the low band signal (S120). Meanwhile, a second analog signal is generated by modulating data input from a terminal generating digital data into a high frequency signal of 6 to 32 Hz (S130), and passing the generated second analog signal through a high frequency filter. The signal is filtered by excluding the signal except for the high band signal (S140). A transmission signal is generated so that the generated first analog signal and the second analog signal do not overlap each other, and the generated transmission signal is simultaneously transmitted through one communication line (S150).

4 shows an example of a transmission signal according to the present invention. Referring to FIG. 4, the first analog signal is disposed in a low band of 0 to 6 Hz and the second analog signal is disposed in a high band of 6 to 32 Hz. Therefore, the first analog signal and the second analog signal can be simultaneously transmitted through one communication line.

Meanwhile, the above-described embodiments of the present invention can be written as a program that can be executed in a computer, and can be implemented in a general-purpose digital computer that operates the program using a computer-readable recording medium.

The computer-readable recording medium may include a magnetic storage medium (eg, ROM, floppy disk, hard disk, etc.), an optical reading medium (eg, CD-ROM, DVD, etc.) and a carrier wave (eg, the Internet). Storage medium).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

110, 120: terminal
210, 220: variation demodulation
300: simultaneous transmission unit
310: low frequency filter unit 320: high frequency filter unit
330: transmission signal generator 400: network
500: external terminal

Claims

Low frequency modulating the analog surveillance image to generate a low band communication signal, and passing the generated low band communication signal to a low frequency filter;
High frequency modulation of the digital signal to generate a high frequency band communication signal, and passing the generated high frequency communication signal through a high frequency filter; And
And generating and transmitting the low-band signal and the high-band signal so that frequency bands do not overlap each other on the same communication line.

The method of claim 1,
The analog surveillance image is modulated into a low band communication signal having a frequency of 0 to 6Hz,
And the digital signal is modulated into a high band communication signal having a frequency of 6 to 32 Hz.