KR20010103954A - A communication system and method for communicating between subscribers via one cable - Google Patents

Abstract

The present invention relates to a communication system and a method in which a plurality of subscriber units are connected through one communication cable, and each subscriber unit communicates with a communication counterpart subscriber unit using a frequency division multiple access scheme.

The communication method according to the present invention is a communication method applied to a communication system in which a plurality of subscriber units are branched and combined on at least one communication cable, wherein the first subscriber unit is a call counterpart using information input from a user. A first step of obtaining information of two subscriber units; A second step of the first subscriber unit confirming whether the second subscriber unit is busy by using the obtained information; The first subscriber unit continuously monitors the reception signal when the second subscriber unit is busy, sets the reception channel as its own reception channel if the second subscriber unit is not busy, and sets the transmission channel to the Setting to a reception channel of an acquired second subscriber unit; A fourth step of transmitting, by the first subscriber unit, a call channel establishment request message including unique identifier information and unique identifier information of the second subscriber unit through the set transmission channel; When the second subscriber unit receives a call channel establishment request message having a destination identifier equal to its own unique identifier, the reception channel information of the first subscriber unit is determined using the unique identifier information of the first subscriber unit included in the message. A fifth step of obtaining; A sixth step of setting, by the second subscriber unit, its transmission channel as a reception channel of the obtained first subscriber unit, and sending a response message; And a seventh step of releasing the call channel and switching to the initial state when the call ends in the call state.

Description

Communication system and method for communication between subscribers through one cable {A COMMUNICATION SYSTEM AND METHOD FOR COMMUNICATING BETWEEN SUBSCRIBERS VIA ONE CABLE}

The present invention relates to a communication system and method for communicating between subscribers through one cable, and more particularly, a plurality of subscriber units are connected through one communication cable such as a coaxial cable, and each subscriber unit is frequency division multiplexed. A communication system and a method for communicating with a communication counterpart subscriber unit using a connection method.

The most commonly used communication networks are circuit switched networks such as public switched telephone networks (PSTN) and packet switched networks in asynchronous transfer mode (ATM). The circuit switching method enables communication by connecting actual circuits between units for communication, and the packet switching method uses a communication line (for example, a coaxial cable or an optical cable) capable of high-speed data transmission. Packetizes the information of many terminals and transmits them simultaneously through one communication line.

It is estimated that there are currently 19 million Internet users in Korea, and as many people use the Internet, users are demanding higher speed communication services. In order to satisfy the demands of the Internet users, communication networks that can provide significantly faster data transmission and various services than the existing telephone modems are limited. For example, a cable that realizes a transmission speed of up to 30Mbps using a cable TV network, a digital subscriber network (xDSL) or wireless data that can transmit MPEG level video signals in real time while using a telephone line as it is. And a wireless subscriber network (WLL) for implementing a telephone network. Such a wide area network basically has a service provider, and provides a communication service to subscribers by cable, telephone line, and wireless. For example, in the case of a cable modem using a cable TV network, a service provider transmits a communication signal to each subscriber's home by using a device that interworks a cable network with an internet network at a cable broadcasting station, and the subscriber receives a cable channel through the cable modem. 1-2 of them will be used for Internet communication.

However, these conventional communication networks require a lot of initial costs because expensive equipment has to be installed in order to provide communication services to subscribers, and there are problems such as additional circuits to expand the number of subscribers.

Accordingly, the present invention is to solve the problems of the prior art as described above, an object of the present invention is a communication system and a method that allows a plurality of subscribers to communicate over a single communication cable using frequency division multiple access technology To provide.

1 is a schematic network diagram for explaining a communication system according to the present invention;

2 is a detailed block diagram of a subscriber unit according to the present invention;

3 is a process flow diagram for communicating between subscribers in accordance with the present invention.

* Explanation of symbols for main parts of the drawings

1: duplexer 2: first variable reference frequency generator

3: downconverter 4: intermediate frequency (IF) processing unit

5: control unit 6: interface

7: EEPROM 8: RAM

9 second variable reference frequency generator 10 upconverter

According to an aspect of the present invention, there is provided a communication system in which a plurality of subscriber units are branched and combined on at least one communication cable, the subscriber unit comprising: control means; At least one reference frequency generating means generated by varying the reference frequency according to the control of the control means; Means for downconverting the received signal according to the reference frequency provided from the reference frequency generating means; Means for upconverting a signal to be transmitted according to a reference frequency provided from said reference frequency generating means; And memory means for storing unique identifier information for each subscriber unit and reception channel information corresponding to each subscriber unit, wherein the control means uniquely assigns its own reception channel to itself when a call is made with the other party. It is characterized in that it is set to the received channel, and its transmission channel is set to a reception channel uniquely assigned to the subscriber unit of the call counterpart so as to control communication.

In addition, the communication method according to the present invention is a communication method applied to a communication system in which a plurality of subscriber units are branched and combined on at least one communication cable, wherein the first subscriber unit uses the information input from the user to the call counterpart. Acquiring information of a second subscriber unit; A second step of the first subscriber unit confirming whether the second subscriber unit is busy by using the obtained information; If the first subscriber unit is busy, the reception signal is continuously monitored; if not, the reception channel is set to a reception channel uniquely assigned to itself, and the transmission channel is uniquely assigned to the second subscriber unit. Setting a channel; A fourth step of transmitting, by the first subscriber unit, a call channel establishment request message including unique identifier information and unique identifier information of the second subscriber unit through the set transmission channel; When the second subscriber unit receives a call channel establishment request message having a destination identifier equal to its own unique identifier, the reception channel information of the first subscriber unit is determined using the unique identifier information of the first subscriber unit included in the message. A fifth step of acquiring a second channel by the second subscriber unit as a reception channel of the first subscriber unit and transmitting a response message; And a seventh step of releasing the call channel and switching to the initial state when the call is terminated in the call state.

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

1 is a schematic diagram illustrating a communication system according to the present invention.

The inventor of the present invention solves this problem by combining a technology commonly used in wireless communication with a wired communication technology in order to support voice and / or non-voice communication at high speed while minimizing the expansion of communication lines. That is, since wireless communication uses public media that are all identical communication media, various multiple access technologies have been developed and used. Accordingly, the inventors of the present invention have made the present invention with the idea that the multiple access technology used in the wireless communication can be applied to the wired communication line to increase the subscriber problem and the data processing speed.

As shown in Fig. 1, in the communication system according to the present invention, a plurality of subscriber units are branched and coupled to one communication cable (preferably a coaxial cable). Each subscriber unit communicates with a communication counterpart subscriber unit through a different frequency. In this way, a plurality of subscriber units can communicate without frequency interference through one communication cable. Here, the frequency using method may be applied to all the methods used in the conventional wireless communication as it is. Further, in order to increase the number of subscribers by reusing the frequency, it can be simply achieved by adding one or more communication cables. In addition, by providing a signal amplifier at regular intervals according to the transmission distance, it is possible to increase the transmission distance of the signal.

2, a detailed configuration of a subscriber unit according to the present invention will be described.

2 is a detailed block diagram of a subscriber unit according to the present invention, in which 1 is a duplexer, 2 is a first variable reference frequency generator, 3 is a down converter, 4 is an intermediate frequency (IF) processor, 5 is a controller, and 6 A silver interface, 7 denotes an EEPROM, which is an electrically erasable and programmable read-only memory, 8 denotes a RAM, a read-write memory, 9 denotes a second variable reference frequency generator, and 10 denotes an upconverter.

The subscriber unit according to the invention employs a duplexer 1 at the end of the communication cable in order to transmit and receive data via one communication cable. In addition, the reception channel of the subscriber unit according to the present invention is fixed to a channel uniquely assigned to each subscriber unit at normal times, and in order to check whether the other party is busy during the process of establishing a communication channel with the communication counterpart, Change to the receiving channel of the other party, and set the transmission channel to the receiving channel of the communication counterpart. To this end, the down converter 3 of the subscriber unit of the present invention down-converts a signal received in a predetermined band with a frequency supplied from the first variable reference frequency generator 2 operated by the control of the control unit 5. Here, the down converter 3 may be configured as a primary and a secondary down converter according to the frequency used. The down-converted signal by the down converter 3 is amplified and filtered by the intermediate frequency (IF) processor 4 and is provided to the controller 5.

On the other hand, the signal transmitted to the communication counterpart subscriber unit is up-converted by the up-converter 10 and transmitted through the duplexer 1, the up-converter 10 is a second variable operated by the control of the controller 5 The transmission signal is up-converted using the reference frequency supplied from the reference frequency generator 9. Meanwhile, in the present invention, the reference frequency generator is described as being provided on the receiving and transmitting sides, respectively, which may generate different reference frequencies using one reference frequency generator, and this modification will be very obvious to those skilled in the art.

The control unit 5 includes an interface 6 for connecting to an external non-voice or voice communication device, and an EEPROM, which is an electrically erasable and programmable read-only memory that stores a program for performing an overall operation and information on each subscriber unit. (7) and RAM 8 for temporarily storing data are connected.

The control unit 5 is a device such as a central processing unit (CPU) operated according to a program, and the control unit 5 largely performs a reception signal monitoring function, a transmission channel setting function, a data modulation and demodulation control function, and the like. The reception signal monitoring function of the controller 5 refers to a function of continuously monitoring whether a signal having the same destination identifier as its own unique identifier (ID) is received among the signals received through the fixed reception channel.

The operation of the transmission channel setting function is classified according to whether it is the transmitting side or the receiving side. The case of the sender is as follows. When the phone number or the unique number of the other party for the call is input from the external communication device through the interface 6, the controller 5 uses the information input through the interface 6 to identify the unique identifier of the communication party and the other party's communication party. Receive channel information is obtained from the EEPROM 7. Then, the controller 5 controls the first variable reference frequency generator 2 to temporarily change its reception channel to the reception channel of the communication counterpart obtained from the EEPROM 7 and then checks whether there is a reception signal. Check it. If there is a reception signal, the other party's subscriber unit is currently in communication, so that it is in a call. If there is no reception signal, the subscriber unit of the other party's communication is not currently in use, and thus, the first variable reference frequency generator 2 is controlled. The second variable reference frequency generator 9 is controlled at the same time as the reception channel of the mobile station and the transmission channel is set as the reception channel of the call counterpart. Then, a call channel request signal including a unique identifier of the counterpart and its unique identifier information is sent out over the communication cable.

On the other hand, the case of the receiving side is as follows.

If a signal having the same destination identifier (ID) as its own identifier (ID) is received during the monitoring of the receiving channel, a unique identifier (ID) of the other party included in the received signal is detected, and the unique identifier of the other party is added to the unique identifier. The corresponding channel information is retrieved from the EEPROM 7. Then, the second variable reference frequency generator 9 is controlled to set its own transmission channel as the reception channel of the communication counterpart. Then, the channel setting response signal including the unique identifier of the counterpart subscriber unit is sent out through the transmission channel onto the communication cable.

When a transmission / reception channel for communication is established through this process, the control unit 5 controls to demodulate a signal received through the reception channel, and modulates a signal to be transmitted and transmits it through the transmission channel. The modulation / demodulation control function in the control unit 5 is performed by software by a conventional algorithm, and a detailed description thereof will be omitted.

3 is a flowchart illustrating the operation of the control unit as described above in more detail.

First, the controller continuously monitors whether there is a signal received through its own reception channel (101). In this state, when a call channel setting request is received from the user (102), the unique identifier information of the other subscriber unit and the reception channel information of the other subscriber unit are obtained using the telephone number or unique number of the communication counterpart input by the user (103). ). Then, the receiving channel is temporarily set to the receiving channel of the acquired counterpart 104, and it is checked whether the subscriber's subscriber unit of the counterpart is busy by checking whether a signal is detected (105). If the subscriber unit of the other party is busy, it is notified that it is busy (106) and returns to the initial state of monitoring the received signal.

On the other hand, if the subscriber unit of the other party is not in a call, it changes its own reception channel set to the reception channel of the other party to its own reception channel (107) and sets its own transmission channel to the reception channel of the other party ( 108). Then, through the set transmission channel, a unique identifier of a call counterpart is written as a destination identifier, and a call channel setting request message including its own unique identifier is sent as a transmitting side identifier (109). In response to receiving the response message from the communication counterpart subscriber unit in the response waiting state (110), it is notified that the call channel is established and switches to the call state (115).

On the other hand, when a signal having the same destination unique identifier as its own identifier is received in the reception signal monitoring state (111), the unique identifier of the counterpart subscriber unit included in the received message is detected (112). In operation 113, the receiver acquires the reception channel information of the other subscriber unit from the EEPROM by using the detected counterpart's unique identifier, and sets its own transmission channel as the reception channel of the acquired counterpart (113). Then, a response is transmitted 114 to the counterpart subscriber unit via the set transmission channel. When the communication channel is established through the above process, the communication channel is informed that the communication channel is established and the call is displayed (115). When the call is terminated in the call state (116) to initialize the currently set channel to release the communication channel (117), and switches to the initial state to monitor the signal received through its reception channel.

Meanwhile, in the present invention, a plurality of subscriber units are coupled to one communication cable, and each subscriber unit is fixed to a specific transmission channel and a reception channel, and the subscriber unit is set identically to the specific transmission channel and the reception channel. You can think of only communicating between them. That is, when subscriber unit A is set to transmission channel 1 and reception channel 1, and subscriber unit B is also set to transmission channel 1 and reception channel 1, subscriber unit A is set to only the same channel. Another way is to communicate with B only. In this case, a dedicated communication line is used between a specific subscriber and a specific subscriber, and a plurality of subscribers are connected to one communication cable to provide communication only between specific subscribers.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the art without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

According to the present invention as described above, multiple subscribers can communicate using a frequency division multiple access scheme through one communication cable, thereby providing high-speed communication while reducing initial installation and maintenance costs, and expansion of subscribers It has an easy effect.

Claims (6)

A communication system in which a plurality of subscriber units are branched and combined on at least one communication cable, The subscriber unit, Control means; At least one reference frequency generating means generated by varying the reference frequency according to the control of the control means; Means for downconverting the received signal according to a reference frequency provided from said reference frequency generating means; Means for upconverting a signal to be transmitted according to a reference frequency provided from said reference frequency generating means; And Memory means for storing unique identifier information for each subscriber unit and reception channel information corresponding to each subscriber unit; The control means, When the call with the other party set its own receiving channel to the receiving channel uniquely assigned to itself, and sets its own transmission channel to the receiving channel uniquely assigned to the subscriber unit of the call counterpart to control communication. Communication system. The method of claim 1, The control means, Means for monitoring whether a signal having a destination identifier equal to its own unique identifier is received; Transmission channel setting means for acquiring reception channel information uniquely assigned to the counterpart subscriber unit using the received counterpart information and setting its own transmission channel as the reception channel of the acquired counterpart; And And modulation / demodulation control means for controlling modulation / demodulation of transmission and reception signals. The method of claim 2, The transmission channel setting means, The reception channel information uniquely assigned to the counterpart subscriber unit is obtained by using information input at the time of request for setting up a communication channel from the user, and the own reception channel is temporarily changed to the reception channel of the acquired counterpart. And an in-call confirmation means for confirming whether a subscriber unit of the other party is busy by detecting a signal from the other party. A communication method applied to a communication system in which a plurality of subscriber units are branched and combined on at least one communication cable, A first step of obtaining, by the first subscriber unit, information of the second subscriber unit, which is a call counterpart, using information input from the user; A second step of the first subscriber unit confirming whether the second subscriber unit is busy by using the obtained information; If the first subscriber unit is busy, the reception signal is continuously monitored; if not, the reception channel is set to a reception channel uniquely assigned to itself, and the transmission channel is uniquely assigned to the second subscriber unit. Setting a channel; A fourth step of transmitting, by the first subscriber unit, a call channel establishment request message including unique identifier information and unique identifier information of the second subscriber unit through the set transmission channel; When the second subscriber unit receives a call channel establishment request message having a destination identifier equal to its own unique identifier, the reception channel information of the first subscriber unit is determined using the unique identifier information of the first subscriber unit included in the message. A fifth step of obtaining; A sixth step of setting, by the second subscriber unit, its transmission channel as a reception channel of the obtained first subscriber unit, and sending a response message; And Step 7 to release the communication channel and return to the initial state when the call ends in the call state Communication method comprising a. The method of claim 4, wherein The second step, Setting, by the first subscriber unit, its own reception channel as the reception channel of the second subscriber unit using the obtained reception channel information of the second subscriber unit; And Confirming, by the first subscriber unit, that a signal is detected through the set reception channel Communication method comprising a. A communication system in which a plurality of subscriber units are branched and combined on at least one communication cable, The subscriber unit, Control means; At least one reference frequency generating means for generating a reference frequency; Means for downconverting the received signal according to a reference frequency provided from said reference frequency generating means; Means for upconverting a signal to be transmitted according to a reference frequency provided from said reference frequency generating means; And Memory means for storing at least unique identifier information for each subscriber unit, The reference frequency generating means generates a fixed reference frequency, The control means, And control only communication between the subscriber units having the same transmission / reception channel as the transmission / reception channel uniquely assigned thereto.