KR0169677B1 - A digital-dbs receiver - Google Patents

Abstract

The present invention relates to a digital satellite broadcast receiving apparatus, comprising: a tuner (100); A / D converter 102; QPSK demodulator 104; Viterbi / Lead-Solomon decoder 106; Transport stream demultiplexer 108; Decryption unit 110; A bus converter 111; Audio / video decoder 112; Video encoder 114; Modulator 116; D / A converter 118; Audio amplifier 120; Micom 124; Resource and subscriber management system 126; Modem section 128; Smart card 130; And a memory 132, and according to the present invention, by providing an interface between components having different input / output ports, data and control signals are smoothly transmitted between components.

Description

Digital satellite broadcasting receiver

1 is a block diagram of a digital satellite broadcasting system.

2 is a block diagram of a conventional digital satellite broadcasting receiver.

3 is a block diagram of a digital satellite broadcasting receiver according to the present invention.

FIG. 4 is a detailed block diagram of an embodiment of the bus converter shown in FIG.

5 is a circuit diagram of an embodiment of the data latch portion shown in FIG.

* Explanation of symbols for main parts of the drawings

100: tuner 102: A / D converter

104: QPCK demodulator 106: Viterbi / Lead-Solomon decoder

108: transport stream demultiplexer

110: decryption unit 111: bus conversion unit

111-1: Clock divider 111-2: Serial data latch clock generator

111-3: Data latching unit 112: Audio / video decoder

114: video encoder 116: modulator

118: D / A converter 120: audio amplifier

122: remote control 124: microcomputer

126 resource and subscriber management system 128 modem unit

130: smart card 132: memory

The present invention relates to a digital satellite broadcasting receiver, and more particularly, to a digital satellite broadcasting receiver having an interface for smoothly transmitting data and control signals between components having different input / output ports when receiving digital satellite broadcasting. will be.

Direct Broadcasting Service (DBS) refers to a broadcasting method for retransmitting a broadcast signal through a repeater in space for the purpose of receiving it directly in a general home. This becomes possible and widespread.

Satellite broadcasting is impossible to broadcast locally, requires a large investment due to high reliability requirements, and has the disadvantage of radio wave menstruation problems, while it is possible to broadcast uniformly high quality in a large area with a small output compared to terrestrial broadcasting. It is advantageous in that phosphorus reception disturbance and ghost phenomenon can be reduced.

FIG. 1 is a block diagram of a digital satellite broadcasting system, and the digital satellite broadcasting system is composed of three parts. The transmitter 10 converts a television signal into a digital television signal, and transmits the compressed signal to a satellite after transmission. A satellite repeater 20 (Transponder) for receiving and amplifying and retransmitting a signal in outer space: and a receiver 30 (Integrated Receiver Decoder) for receiving and decoding the signal relayed from the satellite.

Here, the transmitter 10 includes a moving picture expert group-2 (MPEG-2) encoder 12, a forward error correction (FEC) encoder 14, a quaternary phase shift keying (QPSK) modulator 16, and a transmission antenna 18. It is composed of

In addition, the receiver 30 includes a receiving antenna 31, a low noise block down converter (LNB) 32, a tuner 34, a QPSK demodulator 36, an FEC decoder 38, and an MPEG-2 decoder 39. do.

The operation of the digital satellite broadcasting system configured as described above is as follows.

The transmitter 10 converts and compresses video, audio, and data signals into digital signals according to the MPGE-2 standard, and configures them into packet streams to create a single digital television signal stream.

Several digital television signal streams are multiplexed into transport stream packets and then channel encoded.

In this case, the transport stream packet is 188 bytes and the effective data rate is about 34 Mpbs.

Channel coding is performed to compensate for errors generated during transmission, and the encoded signal undergoes a modulation process to be transmitted to the satellite.

Transport stream packets are first converted into random data streams during energy dissipation. The 12 GHz band used for the downlink of satellite broadcasting is widely used on the ground, so that it does not interfere with other terrestrial radio communications. You must disperse energy.

After conversion into a random data stream, concatenated convolutional coding and Read-Solomon coding are performed to reduce data errors due to noise and interference. (pulse shaping)

The modulation method uses QPSK because the power of the satellite repeater is limited, so power efficiency is given priority over spectrum.

The modulated signal is converted from the up-converter to the Ku-band (14 GHz) and then amplified sufficiently in a high power amplifier (HPA) to be launched into the satellite via the transmit antenna 18.

The satellite repeater 20 receives and amplifies a signal of 14 GHz, converts it to 12 GHz, and retransmits it to the ground.

The retransmitted signal is received by the home receiving antenna 31, amplified by the LNB 32, converted into a 1 GHz signal, and sent to the tuner 34 via a cable.

The signal selected by the tuner 34 is QPSK demodulated, and the demodulated signal is derandomized after the transmission error is recovered in the FEC decoder 38, and then restored to the MPEG-2 transport stream packet, and then the MPEG-2 decoder. At 39, the video, audio and data signals are decoded.

FIG. 2 is a block diagram illustrating a conventional digital satellite broadcasting receiver. A tuner which receives a transport stream from a satellite (not shown) received from an antenna (not shown) and tunes a transport stream desired by a viewer. 40; An A / D converter 42 for converting the tuned analog signal into a digital signal; A QPSK demodulator 44 which receives the A / D converted QPSK modulated signal and performs QPSK demodulation; A Viterbi / Reed-Solomon decoder 46 which receives the QPSK demodulated Viterbi / Reed-Solomon coded signal and performs Viterbi / Reed-Solomon decoding; A transport stream demultiplexer (48) for receiving and demultiplexing the Viterbi / Lead-Solomon decoded multiplexed transport stream to extract only audio / video data of a channel desired by a viewer; Decryption unit 50 for decrypting the data so that the subscriber can view the encrypted signal received; An audio / video decoder 52 for receiving the extracted audio / video data and performing decoding; A video encoder (54) for encoding the decoded video data into an analog signal for receiving and displaying the decoded video data; A modulator 56 for modulating the video signal and outputting a radio frequency (RF) signal; A D / A converter 58 for receiving the decoded audio data as a digital signal and converting the decoded audio data into an analog signal; An audio amplifier (60) for amplifying the D / A converted audio signal and outputting the amplified audio signal; A microcomputer 64 for controlling the entire system according to the received signal from the remote controller 62; A resource and subscriber management system 66 (REMS) for controlling and monitoring subscriber access to the program and collecting and storing usage information from subscriber receiver units; A modem unit 68 for communication between the resource and subscriber management system and the receiver; A smart card 70 that authorizes decryption of the encrypted data so that only the subscriber who is authorized to receive the data can receive the data, and provides information about the paid program when the subscriber watched it; And a memory 72 in which the program of the microcomputer 64 is stored.

Referring to the operation of the conventional digital satellite broadcast receiver configured as described above, a satellite having a plurality of broadcast satellite repeaters outputs a transport stream multiplexed in multiple channels, the output transport stream is received by an antenna, The tuner 40 tunes the transport stream desired by the viewer.

The tuned analog signal is converted to a digital signal by the A / D converter 42, and passed through a QPSK demodulator 44 and a Viterbi / Lead-Solomon decoder 46 to correct an error generated during transmission.

The Viterbi / Lead-Solomon decrypted transport stream is input to the transport stream demultiplexer 48 to extract only the audio / video data desired by the viewer, and the decryption table 50 allows the viewer to view the encrypted data. Decrypt the data so that

The extracted audio / video data is input to an audio / video decoder 52 and decoded, and then the decoded video data is passed through a video encoder 54 and a modulator 56 which encode an analog signal for display. And the like, and the audio data is output via the D / A converter 58 and the audio amplifier 60.

The microcomputer 64 controls the entire system according to the viewer's manipulation of the remote controller 62, and the modem unit 68 allows communication between the resource and subscriber management system 66 and the receiver.

The resource and subscriber management system 66 controls and monitors subscriber access to the program and collects and stores usage information from subscriber receiver units.

The smart card 70 authorizes the decryption of the encrypted data so that only the subscriber who has the right to receive the data can receive the data, and also stores the data about the paying program when the viewer watches it. Is sent to the resource and subscriber management system 66 to calculate the charge.

If the components in the conventional digital satellite broadcasting receiver as described above have different input / output ports, there is a problem in that data transmission is not performed smoothly.

Accordingly, the present invention has been made to solve the above problems, by providing an interface between the components having different input and output ports to facilitate the transmission of data and control signals between the components of the digital satellite The purpose is to provide a broadcast receiving device.

The digital satellite broadcast receiver of the present invention for achieving the above object comprises: a tuner for receiving a transport stream from a satellite received at an antenna and selecting a transport stream desired by a viewer; An A / D converter converting the tuned analog signal into a digital signal; A QPSK demodulator that receives the A / D converted QPSK modulated signal and performs QPSK demodulation; A Viterbi / Lead-Solomon decoder which receives the QPSK demodulated Viterbi / Lead-Solomon coded signal and performs Viterbi / Lead-Solomon decoding; A transport stream demultiplexer that receives the Viterbi / Lead-Solomon decoded multiplexed transport stream and demultiplexes the audio / video data of a channel desired by a viewer; A decryption unit for decrypting the data so that the subscriber can view the encrypted signal;

A bus converter which serially receives audio data extracted from the transport stream demultiplexer and outputs the audio data in parallel; An audio / video decoder which receives video data extracted from the transport stream demultiplexer and parallel audio data from the bus converter and performs decoding; A video encoder for encoding the decoded video data into an analog signal for receiving and displaying the decoded video data; A modulator for modulating the video signal to output a high frequency signal; A D / A converter which receives the decoded audio data as a digital signal and converts the decoded audio data into an analog signal; An audio amplifier for amplifying the D / A converted audio signal and outputting the amplified audio signal; A microcomputer that controls the entire system according to the received signal from the remote controller; A resource and subscriber management system for controlling and monitoring subscriber access to the program and collecting and storing usage information from subscriber receiving units; A modem unit for communication between the resource and the subscriber management system and the receiver; A smart card that authorizes decryption of the encrypted data so that only subscribers who are authorized to receive the data can receive the data, and provide information about the paid program when the subscriber watches it; And a memory in which the program of the microcomputer is stored.

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

3 is a block diagram of a digital satellite broadcast receiver according to the present invention, wherein the digital satellite broadcast receiver according to the present invention inputs a transport stream from a satellite (not shown) received from an antenna (not shown). A tuner 100 which receives and tunes a transport stream desired by the viewer; An A / D converter (102) for converting the tuned analog signal into a digital signal; A QPSK demodulator (104) for receiving QPSK modulated signals converted into A / D and performing QPSK demodulation; A Viterbi / Lead-Solomon decoder 106 for receiving the QPSK demodulated Viterbi / Lead-Solomon coded signal and performing Viterbi / Lead-Solomon decoding; A transport stream demultiplexer 108 which receives the Viterbi / Lead-Solomon decoded multiplexed transport stream and demultiplexes the audio / video data of a channel desired by a viewer; Decryption unit 110 for decrypting the data so that the subscriber can view the encrypted incoming signal; A bus converter 111 which receives audio data extracted from the transport stream demultiplexer 108 in series and outputs the audio data in parallel; An audio / video decoder (112) for receiving video data extracted from the transport stream demultiplexer (108) and parallel audio data from the bus converter (111) to perform decoding; A video encoder (114) for encoding the decoded video data into an analog signal for receiving and displaying the decoded video data; A modulator 116 for modulating the video signal to output a high frequency signal; A D / A converter 118 for receiving the decoded audio data as a digital signal and converting the decoded audio data into an analog signal; An audio amplifier (120) for amplifying the D / A converted audio signal and outputting the amplified audio signal; A microcomputer 124 for controlling the entire system according to the received signal from the remote controller 122; A resource and subscriber management system 126 that controls and monitors subscriber access to the program and collects and stores usage information from subscriber receiving units; A modem unit 128 for communication between the resource and subscriber management system 126 and the receiver; A smart card 130 that grants the right to decrypt the encrypted data so that only the subscriber having the right to receive the data can receive the data, and provides information about the paid program when the subscriber views the paid program; And a memory 132 in which a program of the microcomputer 124 is stored.

4 is a detailed block diagram of an embodiment of implementing a bus converter of a digital satellite broadcasting receiver according to the present invention, wherein the bus converter 111 includes a clock divider 111-1 for dividing an input clock by eight; A serial data latch clock generator 111-2 receiving an input clock signal and a valid serial data input signal to generate a serial data latch clock signal; The data latch unit 111-3 receives audio data in series according to the serial data latch clock signal and outputs audio data in parallel in accordance with an output enable signal from a microcomputer (shown in FIG. 4).

The serial data latch clock signal generator 111-2 may be implemented as an AND gate.

FIG. 5 is a circuit diagram of an embodiment of the data latch unit shown in FIG. 4. The data latch unit 111-3 has a structure in which eight D-flip flops are connected in series at an input terminal, and eight three at the output terminal. A state buffer is connected to each output of the eight D-flip flops.

Next, the operation and effects of the present invention configured as described above will be described.

The transport stream demultiplexer 108, the bus converter 111, and the audio / video decoder 112, which are the central elements of the present invention, will be examined in detail, and the rest will be omitted because it is similar to the conventional apparatus described above. Let's do it.

Referring to FIG. 3, the transport stream demultiplexer 108 receives a Viterbi / Lead-Solomon decoded multiplexed transport stream and demultiplexes only audio / video data of a channel desired by a viewer.

The bus converter 111 receives audio data serially from audio / video data extracted from the transport stream demultiplexer 108 and outputs the audio data in parallel.

Referring to FIG. 4, the clock divider 111-1 of the bus converter 111 divides the input clock into eight, and the divided clock signal latches parallel audio data. This parallel data latch clock signal latches 8 bits of parallel audio data to the audio decoder in the audio / video decoder 112 (FIG. 3).

In addition, the serial data latch clock generation unit 111-2 of the bus converter 111 receives an input clock signal and a valid serial data input signal, which is a signal that valid audio data is being input, and performs a logical multiplication on the two signals. The serial data latch clock signal is generated. The generated clock signal may latch the serial audio data from the transport stream demultiplexer 108 into the data latch 111-3.

In the data latch section 111-3 of the bus converting section 111, 8 bits of audio data are sequentially serialized to eight D flip-flops (shown in FIG. 5) according to the serial data latch clock signal. The input and output enable signal from the microcomputer (shown in FIG. 4) controls the bus by controlling a three-state buffer consisting of eight at the output stage.

In the audio decoder in the audio / video decoder 112, the data latch unit 111 of the bus converter 111 is output according to the parallel data latch clock signal output from the clock divider 111-1 of the bus converter 111. -3) receives 8-bit parallel audio data and performs decoding.

As described above, according to the present invention, by providing a bus converter that serves as an interface between components having different input and output ports, it is possible to smoothly transmit data and control signals between components. There is.

Claims (4)

A tuner 100 which receives a transport stream from a satellite received at an antenna and tunes a transport stream desired by a viewer; An A / D converter (102) for converting the tuned analog signal into a digital signal; A QPSK demodulator (104) for receiving QPSK modulated signals converted into A / D and performing QPSK demodulation; A Viterbi / Lead-Solomon decoder 106 for receiving the QPSK demodulated Viterbi / Lead-Solomon coded signal and performing Viterbi / Lead-Solomon decoding; A transport stream demultiplexer 108 which receives the Viterbi / Lead-Solomon decoded multiplexed transport stream and demultiplexes the audio / video data of a channel desired by a viewer; Decryption unit 110 for decrypting the data so that the subscriber can view the encrypted incoming signal; A bus converter 111 which receives audio data extracted from the transport stream demultiplexer 108 in series and outputs the audio data in parallel; An audio / video decoder (112) for receiving video data extracted from the transport stream demultiplexer (108) and parallel audio data from the bus converter (111) to perform decoding; A video encoder (114) for encoding the decoded video data into an analog signal for input and display; a modulator (116) for modulating the video signal to output a high frequency signal; A D / A converter 118 for receiving the decoded audio data as a digital signal and converting the decoded audio data into an analog signal; An audio amplifier (120) for amplifying the D / A converted audio signal and outputting the amplified audio signal; A microcomputer 124 for controlling the entire system according to the received signal from the remote controller 122; A subscriber management system 126 and resources for controlling and monitoring subscriber access to the program and for collecting and storing usage information from subscriber receiving units; A modem unit 128 for communication between the resource and subscriber management system 126 and a receiver; A smart card 130 that grants the right to decrypt the encrypted data so that only the subscriber who is authorized to receive the data can receive the data, and provides information about the paid program when the subscriber views the paid program; And a memory (132) storing a program of the microcomputer (124). 2. The apparatus of claim 1, further comprising: a clock divider (111-1) for dividing an input clock by eight; A serial data latch clock generator 111-2 receiving an input clock signal and a valid serial data input signal to generate a serial data latch clock signal; And a data latch unit (111-3) for receiving audio data in series according to the serial data latch clock signal and outputting audio data in parallel according to an output enable signal. The digital satellite broadcasting receiver as claimed in claim 2, wherein the serial data latch clock signal generator (111-2) is implemented with an AND gate. The data latching unit 111-3 has a structure in which eight D-flip flops are connected in series at an input terminal, and eight three-state buffers are provided at the output terminal of each of the eight D-flip flops. Digital satellite broadcasting receiver having a structure connected to an output terminal.