KR19990004470A - LMS subscriber terminal - Google Patents

Abstract

In the LMDS using the broadband-CDMA method, the present invention provides broadcasting, such as telephone, CATV, video on demand (VOD), satellite broadcasting, and the Internet, through the transmission and reception of cell site-end and LMDS signals for the subscriber's home. And a subscriber terminal for LMDS that can provide communication services. The present invention relates to a subscriber integrated terminal for LMDS, wherein the data according to the service request is processed by ATM, W-CDMA baseband processing, DQPSK modulation, and then converted into IF signals of 200 to 400 MHz band. When the signal is up-converted and transmitted to the cell site end through the antenna again, service data according to the corresponding service desired by the subscriber is transmitted from the cell site end to select the corresponding service channel to perform QAM demodulation and W-CDMA baseband processing. After performing the error correction process, the ATM processing is performed, and the ATM processed data is processed for video and audio MPEG-2 decoding signals. Via an Ethernet interface for the subscriber interface or the Internet exchange services for a charge, or services so that subscribers are able to provide the desired digital LMDS services.

Description

LMS subscriber terminal

The present invention is located in the subscriber's home in a local multipoint distribution system (hereinafter referred to as 'LMDS') using a broadband-code division multiple access (CDMA) scheme. Subscribers for LMDS, which can provide broadcasting and communication services such as telephone, CATV, video on demand (VOD), satellite broadcasting, and the Internet through the transmission and reception of cell sites and LMDS signals It relates to a terminal.

Recently, LMDS is adopting wireless access communication method using W-CDMA method of 27.5 ~ 29.5GHz band to perform various LMDS digital services such as CATV, VOD, satellite broadcasting.

On the other hand, the LMDS is composed of a network consisting of LMDS cell units in each region to reach the frequency range, that is, a radius of 5Km in order to implement the LMDS digital service of the nationwide and wide area in the 28GHz band.

Each cell set stage, which is a basic unit of such a network configuration, is located between an LMDS broadcasting station providing an LMDS digital service and a subscriber end receiving a service to transmit / receive a link signal.

However, at this time, each conventional subscriber end is not implemented a multimedia integrated terminal for providing LMDS digital services supported through the cell site end.

Accordingly, the present invention is conceived in view of the above, the subscriber is located in the home and the cell site through the W-CDMA LMDS signal of 27.5 ~ 29.5GHz band through the telephone, CATV, VOD, satellite The present invention provides a subscriber terminal for multimedia type LMDS that can provide broadcasting and communication services such as broadcasting and internet.

In order to achieve the above object, the subscriber synthesis terminal for LMDS according to the present invention performs ATM processing on data according to a corresponding service request, performs W-CDMA baseband processing, and then modulates DQPSK to convert an IF signal in a 200 to 400 MHz band, and again, microwave When the signal is up-converted and transmitted to the cell site end through the antenna, the service data according to the service desired by the subscriber is transmitted from the cell site end to select the corresponding service channel to perform QAM demodulation and W-CDMA baseband processing. Then error correction and then ATM processing, converting the ATM-processed data into video and audio MPEG-2 decoding signal processing, or through the subscriber interface for telephone service or Ethernet interface for Internet service. Characterized in that it can provide.

1 is a block diagram of a subscriber integrated terminal for LMDS (LMDS) according to the present invention.

Explanation of symbols for the main parts of the drawings

1: down converter 2: tuner section

3: demodulation unit 4: first CDMA processing unit

5: error correction unit 6: ATM processing unit

7: Demux 8: video MPEG-2 decoder

9: NTSC encoder 10: audio MPEG-2 decoder

11: adder 12: subscriber interface unit

13: Ethernet interface unit 14: encoder

15: second CDMA processor 16: modulator

17: IF Signal Converter 18: Up Converter

19: remote control 20: remote control

21: smart card 22: safety control

23: control unit

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the subscriber terminal for LMDS according to the present invention.

1 is a block diagram of an LMDS subscriber synthesis terminal according to the present invention, an antenna for receiving a microwave signal in a band of 27.5 to 29.5 GHz, which is a horizontal surface wave transmitted from a cell site terminal (not shown), and the antenna Down converter 1 for down converting the 27.5-29.5 GHz microwave signal received at (Ant) into an intermediate frequency (hereinafter referred to as IF) signal of 950-2050 MHz, and the down converter The tuner unit 2 selects a specific service channel desired by the subscriber from the downlink signal 950 to 2050 MHz in the converter 1, and the service of the IF signal selected by the tuner unit 2 using a QAM demodulator. A demodulator 3 for demodulating a channel into baseband data, a first CDMA processor 4 for W-CDMA baseband processing of the baseband data demodulated by the demodulator 3, and the first CDMA processor ( 4) the error of the baseband processed data in An error correction unit 5 that performs Reed Solomon decoding and convolutional interleaving for data correction and prevention, and data input through the error correction unit 5 or a service request signal of a subscriber ATM cell processing for various data and control data associated therewith and performing switching and multiplexing functions, and ATM cell data processed by the ATM processing unit 6 as video data and audio data. A demux 7 to be separated, a video MPEG-2 decoder 8 for MPEG-2 decoding signal processing of the video data separated from the demux 7, and a video MPEG-2 decoder 8 An NTSC encoder 9 for encoding the video signal decoded by the NTSC composite video signal, an audio MPEG-2 decoder 10 for MPEG-2 decoding signal processing of the audio data separated from the demux 11, NTSC encoder (9) An adder 11 for synthesizing a pre-encoded NTSC video signal and an audio signal decoded by the audio MPEG-2 decoder 10 to provide a CATV or VOD service, and an ATM cell data processed by the ATM processor 6; Subscriber interface unit 12 for interfacing telephone data for providing telephone service, and Ethernet interface unit 13 for interfacing Internet data for internet service provision among ATM cell data processed by ATM processor 6; And the telephone line inputted through the subscriber interface unit 12 or the Ethernet interface unit 13 encodes the ATM cell data of the ATM processing unit 6 which processes the Internet data and the service request signal by the ATM unit. The second CDMA processor 15 for performing W-CDMA baseband processing on the ATM cell data encoded by the encoder 14 and the baseband processed data of the second CDMA processor 15 for DQP. SK, the modulator 16 to modulate and the IF signal converter 17 banded to the IF signal of the 200 ~ 400MHz band modulated by the modulator 16, and the IF signal converted by the IF signal converter 17 It is composed of an up converter (18) for up-converting to a microwave signal of 27.5 ~ 29.5GHz to output to the cell site through the antenna (Ant).

In addition, in performing various LMDS digital services performed by each of the building blocks 1 to 18, a remote controller 19 for remotely controlling channel setting, a service menu selection, and the like, and a remote control output from the remote controller 19. Remote control 20 for outputting a control signal for remotely controlling the operation of each of the building blocks (1 to 18) according to the signal, and the smart service that the service usage information of the subscriber receiving the LMDS digital service is inputted As well as controlling various operations performed by the Security Module 22 which handles the conditional access of the subscriber from the Smart Control 21 and the respective configuration blocks 1 to 18, It further comprises a control unit 23 for performing a remote control of the terminal according to the control signal of the remote control unit 20.

Referring to the operation of the subscriber integrated terminal for LMDS according to the present invention configured as described above are as follows.

Meanwhile, the LMDS subscriber terminal according to the present invention selects a traffic channel that provides a corresponding service with a frequency and Walsh code through a pilot, sink, and paging channel. Apply for and receive CATV, VOD and Internet services.

For the telephone service, the monitoring channel must be kept open to detect the other party's signal, and the sleep mode should be taken to prevent inefficient power loss.

When the subscriber requests the desired service as described above, the LMDS integrated terminal receives the W-CDMA LMDS service signal transmitted from the cell site as a horizontally polarized microwave signal in the 27.5 to 29.5 GHz band through the antenna. Receive.

On the other hand, when the antenna (Ant) is used as a transmission / reception integrated type, the up / down converter (1, 18) should have a built-in duplex function for separating input / output, and at this time, the up / down converter (1) 18) is powered by a DC power supply and must be supplied by the LMDS terminal.

Subsequently, the down converter 1 down-converts the microwave signal in the 27.5-29.5 GHz band to an IF signal having a 950 to 2050 MHz band, and in the tuner unit 2, a subscriber is converted from the IF signal in the converted 950 to 2050 MHz band. Select the specific service channel you requested.

The service channel of the IF frequency band selected by the tuner unit 2 is demodulated by the QAM demodulator of the demodulator 3 and converted into baseband data, and then W-CDMA baseband processed by the first CDMA processor 4. .

ATM cell data converted into baseband data through the error correction unit 5 is output to the ATM processor 6 after Reed Solomon decoding and convolutional interleaving for error correction and prevention.

In this case, when convolutional decoding is performed, descrambling for energy despreading is performed.

Then, the ATM processor 6 processes ATM data through the error correction unit 5 and decodes ATM cell processed data whose CATV, satellite broadcasting, and VOD data support AAL5 through the demux 7. The video signal and the audio signal are separated and output to the video MPEG-2 decoder 8 and the audio MPEG-2 decoder 10, respectively.

Accordingly, the video MPEG-2 recorder 8 processes the video signal output through the demux 7 to receive a video program such as CATV, satellite broadcasting, and VOD service, and then processes MPEG-2 decoded signal, and then NTSC. The encoder 9 converts the NTSC composite video signal.

The audio MPEG-2 decoder 10 also processes an audio signal through an MPEG-2 decoding signal, synthesizes the video signal converted by the NTSC encoder 9 through an adder 11, and performs CATV, satellite broadcasting, and VOD services. Make sure you provide the right services.

On the other hand, when the data processed and output by the ATM processing unit 6 is AAL1, which is telephone or Internet data, the subscriber interface unit 12 or the Ethernet interface unit 13 interfaces with the subscriber to subscribe to the corresponding telephone or Internet service. To be provided.

In contrast to the process of receiving the LMDS digital service at the cell site end, the ATM processor 6 transmits uplink data according to service request signals such as a telephone, the Internet, a VOD control signal, and a signaling signal from the subscriber to the cell site end. The ATM cell processes the uplink data to the encoder 15.

Accordingly, the encoder 15 performs scrambling, convolutional encoding, convolutional interleaving, and Reed Solomon encoding, respectively, and outputs data to the second CDMA processing unit 15, and thus the second CDMA processing unit 15 W-CDMA spread modulation is performed to output W-CDMA baseband processed data to the modulator 16.

Then, the W-CDMA baseband processed data input to the modulator 16 is DQPSK modulated and converted into IF signals in the 200 to 400 MHz band through the IF signal converter 17.

The converted IF signal is up-converted into a microwave signal in the 27.5 to 29.5 GHz band through the up converter 18 and transmitted to the cell site through the antenna Ant.

On the other hand, the control unit 23 for controlling the operation of the configuration block (1 to 18) is used for the multi-processing RISC chip, etc., and has excellent performance and functions, such as the processing speed, including various controls and functions made in the terminal The subscriber state access function using the smart card 21 can be processed.

It also supports a user interface application program that can navigate menus on the TV.

The remote controller 19 may remotely control channel setting or service menu selection.

As described above, the subscriber synthesis terminal of the present invention is located in the subscriber's home and communicates and broadcasts such as telephone, CATV, satellite broadcasting, VOD, Internet, etc. through cell site-end and W-CDMA LMDS signal transmission / reception. The service can be easily provided to the subscriber.

Claims (2)

An antenna (Ant) for receiving a microwave signal transmitted from the cell site end, a down converter (1) for down-converting the microwave signal received at the antenna (Ant) to an IF signal, and a down converter (1) A tuner unit 2 for selecting a specific service channel desired by the subscriber from an IF signal, and a demodulator 3 for demodulating the service channel of the IF signal selected by the tuner unit 2 to baseband data using a QAM demodulator And a first CDMA processor (4) for W-CDMA baseband processing of the baseband data demodulated by the demodulator (3), and error correction and prevention of baseband processed data in the first CDMA processor (4). The error correction unit 5 performs Reed Solomon decoding and convolutional interleaving, and various data according to the data inputted through the error correction unit 5 or the service request signal of the subscriber and related thereto. ATM cell processing for ATM data, and switching and multiplexing functions; ATM processor 6 for separating the ATM cell data processed by the ATM processor 6 into video data and audio data; And a video MPEG-2 decoder (8) for processing MPEG-2 decoding signals on the video data separated by the demux (7), and a video signal decoded by the video MPEG-2 decoder (8) as an NTSC composite video signal. An NTSC encoder 9 for encoding, an audio MPEG-2 decoder 10 for MPEG-2 decoding and time-decoding audio data separated from the demux 7, and an NTSC video signal encoded in the NTSC encoder 9; An adder 11 for synthesizing the voice signal decoded by the audio MPEG-2 decoder 10 to provide a CATV or VOD service, and telephone data for providing a telephone service among ATM cell data processed by the ATM processor 6; Interface Is the subscriber interface unit 12, the Ethernet interface unit 13 for interfacing Internet data for providing Internet service among the ATM cell data processed by the ATM processor 6, and the subscriber interface unit 12 or Ethernet interface. An encoding unit 14 for encoding ATM cell data of an ATM processing unit 6 which processes telephone or Internet data and service request signals input through the unit 13, and an ATM encoded by the encoding unit 14; A second CDMA processor 15 for performing W-CDMA baseband processing, a modulator 16 for performing DQPSK modulation on baseband-processed data in the second CDMA processor 15, and the modulator 16 An IF signal converter 17 for converting the modulated signal to an IF signal, and an up-converter for up-converting the IF signal converted by the IF signal converter 17 into a microwave signal and outputting it to the cell site end through the antenna Ant. 18 and, MD S. El subscriber terminal for synthesis (LMDS), characterized in that comprising the above-mentioned respective structures controller 23 for controlling the various operations carried out by the block (1-18). The remote control unit (19) according to claim 1, further comprising: a remote controller (19) for remotely controlling channel setting, service menu selection, etc. in performing various LMDS digital services performed by the respective building blocks (1-18). The remote control unit 20 for outputting a control signal for remotely controlling the operation of each of the building blocks 1 to 18 according to the remote control signal outputted, and the smart phone to which the service usage information of the subscriber who receives the LMDS digital service is input. And a safety control unit (22) for processing the state connection of the subscriber from the card (21).