KR19990004506A - Video telephony devices for wireless local loop terminals - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

Wireless Local Loop System

2. The technical problem to be solved by the invention

Since the data transmission is made by connecting to the RJ-11 port and the RJ-45 port in the video telephony device of the conventional WLL system, the transmission speed is slow and the price of the product is provided by providing the video telephony service through the modem or the ISDN adapter This is to solve the rising problem.

3. Summary of Solution to Invention

A video telephone apparatus of a wireless local loop system, comprising: a micro controller (204) for controlling the overall operation of the video telephone apparatus; A video capture unit 205 for capturing a video signal from data transmitted through the camera 200; An analog / digital converter 206 for converting the analog voice transmitted from the handset 203 into digital voice data; An echo canceller 207 for canceling echoes of digital voice data; A video compression unit (208) for compressing the video signal captured by the video capture unit (205) to be transmitted at high speed; An audio compressor 209 for compressing the audio data from which the echo is removed by the echo filter 207 to be transmitted at high speed; A multiplexer (210) for multiplexing data through the video compressor (208) and the audio compressor (209); A high speed data port interface unit 211 that interfaces data to be transmitted and received between one subscriber and a counterpart subscriber at a high speed according to the control of the micro controller 204; A demultiplexing unit 212 for demultiplexing the data of the other party's video telephone apparatus transmitted to the apparatus; A video reconstructing unit (213) for reconstructing the compressed video data among the demultiplexed data by the demultiplexing unit (212); An audio restoring unit (214) for restoring compressed audio data among demultiplexed data in the demultiplexing unit (212); A video overlay unit (215) for overlaying the video signal captured by the video capture unit (205) and the video signal decompressed by the video reconstructor (213); A liquid crystal controller 216 for outputting video data through the video overlayer 215 to the liquid crystal display 201; An NTSC decoding unit 217 for encoding the video data through the video overlay unit 215 in the National Television System Committee (NTSC) format and outputting the encoded video data to the TV 202; The digital / analog converter 218 converts the digital audio signal through the audio recovery unit 214 into an analog audio signal.

4. Important uses of the invention

It is applied to a video telephone apparatus for a WLL terminal.

Description

Video telephony devices for wireless local loop terminals

The present invention implements a high speed data port interface of a subscriber access device in a wireless local loop system and a high speed data port interface for interfacing a video telephone device, thereby connecting to a high speed data shaft to transmit data at high speed. Loop) to provide a video telephone device for a terminal.

In general, a wireless local loop (hereinafter, referred to as WLL) system is a system that wirelessly accepts data, voice, image data, and the like to serve a subscriber.

1 is a block diagram of a typical wireless local loop system.

As shown in the drawing, the subscriber access device 10 receives the subscriber's data through the line, converts the received data into airwaves, and delivers the subscriber data propagated in the subscriber access device 10 to the counterpart subscriber. A base station 40, 45, 50 for propagating to the subscriber access device, a base station controller 55 for controlling the plurality of base stations 40, 45, 50, and the subscriber data for a public switched telephone network. And a WLL gateway 80 for interfacing to 85, and a data interface 60 for interfacing the subscriber data to the common switched data network 65.

As shown in FIG. 2, the subscriber access device 10 includes a subscriber interface 15 for receiving data from a subscriber, and an alarm processor for processing an alarm signal generated by the subscriber interface 15; 28), a pulse code conversion unit 20 for pulse code conversion of analog data transmitted from the subscriber interface unit 15, the data through the subscriber interface unit 15 and the pulse code conversion unit 20 Air-wave conversion for converting the data through the CD and modem unit 32 and the CD-A modem unit 32 into a high frequency so as to propagate air into the air. And a signal amplifying section 36 for amplifying the level of the signal converted by the air wave surface bearing section 34.

In addition, the subscriber interface unit 15 includes an ISDN interface 11 for accommodating subscriber data for a general information communication network, a general telephone interface 12 for receiving voice data through a regular telephone, and the general telephone interface. It consists of a tone generator 13 for generating a tone during the operation of (12), and a serial input / output unit 14 for receiving high-speed data in series through a computer or a terminal.

In the above, the ISDN interface 11 has an RJ-45 port, which is an ISDN port, to provide an ISDN service, and the telephone interface 12 has an RJ-11 port for providing a general telephone service. The unit 14 has a port for RS-232C to transmit high speed image data and image data.

Fig. 3 is a block diagram of a conventional video telephone apparatus equipped with a modem.

As shown, the micro-controller 104 controls the overall operation of the video telephone apparatus, the video capture unit 105 for capturing a video signal from the data transmitted through the camera 100, and the handset l03. An analog / digital converter 106 for converting the analog voice into digital data, an echo canceller 107 for canceling echoes of the digital voice data, and a video signal captured by the video capture unit 105 Video compression unit 108, an audio compression unit 109 for compressing the audio data from which echo is removed from the echo canceller 107, and through the video compression unit 108 and the audio compression unit 109 The multiplexer 110 multiplexes data, and the WLL subscriber accesses the video and audio signals multiplexed by the multiplexer 110 under the control of the microcontroller 104 through a telephone line. Modem 111 to be transmitted to the port for the dental general phone, a relay driver 112 for controlling the transmission of data between the modem 111 and the WLL network under the control of the micro-control unit 104, and the increase driver 112 A switch 113 for performing an operation according to the control of the demultiplexer, a demultiplexer 1 [4] which demultiplexes data of a video call device of the other party transmitted through the modem 111, and the demultiplexer 114. A video restoring unit (115) for restoring compressed video data among demultiplexed data in the demultiplexing unit, an audio restoring unit (116) for restoring compressed audio data among demultiplexing data in the demultiplexing unit (114); The video overlay unit 117 overlays the video signal captured by the video capture unit 105 and the video signal decompressed by the video reconstructor 115, and the video data through the video overlay unit 117. (101 The NTSC decoding unit 119 for encoding the video data through the video overlay unit 117 by NTSC (National Television Systenl Committee) method and outputting the video data to the TV 102; The digital / analog converter 120 converts the digital audio signal through the audio recovery unit 116 into an analog audio signal.

The operation of the conventional video telephone apparatus configured as described above is as follows.

First, the micro controller 104 connects the switch 113 through the relay driver 112 so that a call path is formed between the modem 111 and the subscriber access device 10. The modem 111 then operates such that the subscriber access device 10 is connected to the other party's video telephone device. In this way, when a call path is formed with the counterpart video telephone apparatus, the video capturing unit 105 captures a video signal of data transmitted through the camera 100.

In addition, the analog-to-digital converter 106 converts analog voice data transmitted through the handset 103 into digital voice data, removes echoes, and transmits the echo to the audio compressor 109. Thus, the video compressor 108 compresses the video signal and delivers it to the multiplexer 110, and the audio compressor 109 compresses the audio signal and delivers the audio signal to the multiplexer 110. Then, the multiplexer 110 multiplexes the compressed video signal and the audio signal to the modem 111.

The modem 111 transmits the multiplexed data to the subscriber access device 10, and the subscriber access device 10 converts the received data into airwaves to propagate the data to the air and then propagates it to the base station 40. do. Then, the base station 40 delivers the data to the corresponding subscriber access device under the control of the base station controller 55, and delivers the data to the counterpart video telephone apparatus.

On the other hand, when data is received from the partner video telephone apparatus via the subscriber access device 10, the modem 111 transfers the received data to the demultiplexer 114. The demultiplexer 114 demultiplexes the received data and transfers the received data to the video decompressor 115 and the audio decompressor 116 to decompress the video signal and the audio signal. Thus, the decompressed video signal is output to the TV 102 or the liquid crystal display 101, and the decompressed audio signal is converted into an analog voice signal after the echo is removed and output to the handset 103. In this manner, the WLL subscriber access device is connected through a modem to provide a video telephone service.

However, such a conventional video telephone apparatus has a problem in that video communication is not performed in real time because only 4 to 5 frames / sec screen can be transmitted since data is transmitted and received through an RJ-11 port having a data transmission rate of 33600bps.

In addition, since the modem is installed in the video telephone apparatus to provide a video telephone service, there is a problem in that the price of the product is increased.

Accordingly, the present invention has been proposed to solve the above problems, and an object of the present invention is to implement a high-speed data port interface unit for interfacing a high-speed data port of a subscriber access device and a video telephone device in a wireless local loop system. The present invention provides a video telephone apparatus for a wireless local loop terminal connected to a port for high speed data and transmitting data at high speed.

Technical means for achieving the object of the present invention, the micro-controller for controlling the overall operation of the video telephone apparatus; A video capture unit for capturing a video signal from data transmitted through the camera; An analog / digital converter for converting the analog voice transmitted from the handset into digital voice data; An echo canceller for canceling echoes of digital voice data; A video compressor for compressing the video signal captured by the video capture unit to be transmitted at high speed; A video compression unit for compressing the audio data from which the echo is removed by the echo cancellation unit to be transmitted at high speed; A multiplexer which multiplexes data through the video compressor and the audio compressor; A high speed data port interface unit for interfacing data transmission and reception between one subscriber and the other subscriber under high speed according to the control of the micro controller; A demultiplexer which demultiplexes the data of the opposite video telephone apparatus, which is transmitted at high speed through the high speed data port interface; A video decompressor for restoring compressed video data among demultiplexed data by the demultiplexer; An audio decompressor for restoring compressed audio data among demultiplexed data by the demultiplexer; A video overlay unit for overlaying the video signal captured by the video capture unit and the decompressed video signal in the video reconstruction unit; A liquid crystal controller which outputs video data through the video overlay unit to a liquid crystal display; An NTSC decoder which encodes video data through the video overlay unit and outputs the TV data; A digital / analog converter converts the digital audio signal through the audio recovery unit into an analog audio signal.

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

1 is a block diagram of a typical wireless local loop system;

2 is a block diagram of a subscriber access device in a general wireless local loop system;

3 is a block diagram of a conventional video telephone apparatus for a telephone line in a wireless local loop system;

4 is a block diagram of a video telephone apparatus for a wireless local loop terminal according to the present invention;

5 is a flowchart illustrating an interface operation between a video telephone apparatus and a subscriber access apparatus in a wireless local loop system according to the present invention.

Explanation of symbols for the main parts of the drawings

200: camera 201: liquid crystal display

202: Steve 203: handset

204: micro control unit 205: video capture unit

206: analogue / digital converter 207: echo canceller

208: video compression unit 209: audio compression unit

210: multiplexer 211: port interface for high-speed data

212: demultiplexer 213: video restoration unit

214: Audio restoration unit 215: Video overlay unit

216: Liquid crystal control unit 217: NTSC decoding unit

218: Digital / analog converter

4 is a block diagram of a video telephone apparatus for a wireless local loop terminal according to the present invention.

As shown, the micro control unit 204 controls the overall operation of the video telephone apparatus, the video capture unit 205 for capturing a video signal from the data transmitted through the camera 200, and the handset 203. An analog / digital converter 206 for converting the analog voice into digital voice data, an echo canceller 207 for canceling echoes of the digital voice data, and a video signal captured by the video capture unit 205. The video compression unit 208 compresses the transmission to be transmitted at high speed, the audio compression unit 209 compresses the audio data from which the echo is removed by the echo canceller 207 to be transmitted at high speed, and the video compression unit 208. And a multiplexing unit 210 for multiplexing data through the audio compression unit 209 and transmission of data between one subscriber and the other subscriber under the control of the micro controller 204. A high speed data port interface unit 211 for interfacing scenes at high speed, and a demultiplexer 212 for demultiplexing data of an opposite video telephone apparatus transmitted at high speed through the high speed data port interface unit 211. And a video restoring unit 213 for restoring the compressed video data among the demultiplexed data by the demultiplexer 212 and restoring the compressed audio data among the demultiplexed data in the demultiplexing unit 212. An audio reconstructor 214, a video overlayer 215 for overlaying the video signal captured by the video capturer 205 and the video signal decompressed by the video reconstructor 213, and the video overlayer ( The liquid crystal controller 216 for outputting video data through the 215 to the liquid crystal display 201, and NTSC (National Tel) for the video data through the video overlay 215. NTSC decoder 217 that encodes the TV to the TV 202 and outputs it to TV 202, and a digital / analog converter 218 for converting a digital audio signal through the audio reconstructor 214 into an analog audio signal. It consists of.

The operation of the video telephone apparatus for WLL terminal according to the present invention configured as described above is as follows.

First, under the control of the micro controller 204, the high speed data port interface 211 is connected to the RS-232C port, which is a high speed data port of the subscriber access device 10 in the WLL system, as shown in FIG. Set up the connection. In this way, the video telephone apparatus is connected to another terminal in the WLL system at a transmission rate of 144 Kbps. The video capture unit 205 then captures a video signal of the data transmitted through the camera 200. In addition, the analog-to-digital converter 206 converts the analog voice data transmitted through the handset 203 into digital voice data, removes echoes, and transmits the echo to the audio compressor 209. Thus, the video compressor 208 compresses the video signal and delivers it to the multiplexer 210, and the audio compressor 209 compresses the audio signal and delivers the audio signal to the multiplexer 210.

Then, the multiplexer 210 multiplexes the compressed video signal and the audio signal, respectively, and delivers them to the high speed data port interface 211.

Accordingly, the high speed data port interface unit 211 transmits the multiplexed data to the subscriber access device 10 at high speed through the speed data port, and the subscriber access device 10 propagates the data received at high speed to the air. After converting to airwaves to propagate to the base station 40. Then, the base station 40 delivers the data to the corresponding subscriber access device under the control of the base station controller 55, and delivers the data to the counterpart video telephone device.

On the other hand, when data is received at the subscriber access device 10 at high speed from the opposite video telephone device, the high speed data port interface unit 211 receives data at high speed through the RS-232C port, which is a high speed data port, and simultaneously demultiplexes the data. Transfer to section 212. The demultiplexer 212 demultiplexes the received data and transfers the received data to the video decompressor 213 and the audio decompressor 214 to decompress the video signal and the audio signal. Thus, the decompressed video signal is output to the TV 202 or the liquid crystal display 201, and the decompressed audio signal is converted to an analog voice signal and then output to the handset 203 after the echo is removed. In this manner, the WLL subscriber access device is connected via the high speed data port interface to provide a video telephone service.

As described in detail above, the present invention has an effect of performing high-speed data transmission by implementing a high-speed data port interface unit that interfaces with a high-speed data port of a subscriber access device in a wireless local loop system.

In addition, since data is transmitted at high speed, there is an effect of providing a video telephone service that is executed in real time.

In addition, the cost can be reduced by implementing a high speed data port interface that can be connected to RS-232C.

Claims (1)

A video telephone apparatus of a wireless local loop system, comprising: a micro controller (204) for controlling the overall operation of the video telephone apparatus; A video capture unit 205 for capturing a video signal from data transmitted through the camera 200; An analog / digital converter 206 for converting the analog voice transmitted from the handset 203 into digital voice data; An echo canceller 207 for canceling echoes of digital voice data; A video compression unit (208) for compressing the video signal captured by the video capture unit (205) to be transmitted at high speed; An audio compressor 209 for compressing the audio data from which the echo is removed by the echo canceller 207 to be transmitted at high speed; A multiplexer (210) for multiplexing data through the video compressor (208) and the audio compressor (209); A high speed data port interface unit 211 for interfacing data transmission and reception between one subscriber and the other subscriber according to the control of the micro controller 204; A demultiplexer (212) for demultiplexing the data of the opposite video telephone apparatus which is transmitted at high speed through the high speed data port interface (211); A video reconstructing unit (213) for reconstructing the compressed video data among the demultiplexed data by the demultiplexing unit (212); An audio restoring unit (214) for restoring compressed audio data among demultiplexed data in the demultiplexing unit (212); A video overlay unit (215) for overlaying the video signal captured by the video capture unit (205) and the video signal decompressed by the video reconstructor (213); A liquid crystal controller 216 for outputting video data through the video overlayer 215 to the liquid crystal display 201; An NTSC decoder 217 for encoding video data through the video overlayer 215 and outputting the encoded video data to the TV 202; And a digital / analog converter (218) for converting a digital audio signal through the audio recovery unit (214) into an analog audio signal.