KR20050045342A - Apparatus for receiving simultaneously digital broadcasting signal and analogue broadcasting signal - Google Patents

Abstract

The present invention relates to an apparatus for allowing a receiver of a set-top box to have a digital tuner and an analog broadcast signal, respectively, so that the digital broadcast and analog broadcast can be simultaneously viewed.

A tuner unit of the broadcast receiving apparatus according to the present invention includes a first tuner and a first demodulator in charge of an analog broadcast signal, and includes a second tuner and a second demodulator in charge of a digital broadcast signal, the plurality of tuners and demodulators. Is integrally included in the tuner unit.

According to the present invention, it is possible to enhance the market competitiveness due to the improved function of the set-top box, to reduce the size of the set-top box, it is possible to reduce the heat generated by reducing the power consumption of the product.

Description

Apparatus For Receiving Simultaneously Digital Broadcasting Signal And Analogue Broadcasting Signal}

The present invention relates to an apparatus for operating two functions with one tuner, and more particularly, at the receiving end of the set-top box, each tuner in charge of a digital broadcast signal and an analog broadcast signal is simultaneously broadcast and digital broadcast. It relates to a device for viewing.

The present invention is increasing the tendency to add more complex and unique features to the entertainment products used in the home as the level of consumer needs and the development of peripheral technology.

In other words, each product acts as a home server.

Conventional Set Top Box products offer a choice of satellite reception, cable input, or terrestrial to add front-end functionality. In addition, by adding a DVDP (Digital Video Disk Player), an external input, etc., the user can select between analog and digital.

As shown in FIG. 1, the digital / analog tuner unit 100 of the conventional set-top box includes an input terminal 101 capable of receiving both a digital broadcast signal and an analog broadcast signal, and a digital signal through the input terminal 101. A tuner 110 capable of receiving and tuning both a broadcast signal and an analog broadcast signal; an analog demodulator 120 capable of demodulating the tuned analog broadcast signal; And a digital demodulator 130 capable of demodulating the tuned digital broadcast signal. Although a conventional set-top box can synchronize both a digital broadcast signal and an analog broadcast signal with a single tuner, it is not possible to synchronize an analog broadcast signal while synchronizing a digital broadcast signal. The broadcast signal cannot be synchronized.

The conventional set-top box as described above has the following problems. First, the product required in the market requires the input of multiple contents in order to satisfy the function of the personal video recorder (PVR), but it is difficult to enjoy two contents at the same time because only one content can be selected by the conventional tuner. There are many. Second, there is a burden of adding a separate tuner in order to satisfy a separate function according to market demand. Third, more input terminals are required because the number of contents provided by the server is greater than the number of clients, that is, the number of clients that receive and display broadcast signals. If a plurality of tuner unit 300 is separately installed, the competitiveness of the product is weakened and it is difficult to enter the existing market.

In order to satisfy the desire of the general user to enjoy various contents, the user should have as many frontend functions as possible. Only then can the user select the desired content through the input of various paths.

Therefore, it is necessary to implement a lot of content using a small number of frontends. To this end, it is necessary to develop a device that can utilize two functions at the same time using one tuner unit 300.

The present invention was made in view of the above problems, and an object thereof is to provide a device capable of simultaneously demodulating a plurality of contents by adding a simple input terminal and a tuner.

In addition, an object of the present invention is to provide a device that can reduce the volume of the product in the implementation of a home server product is easy to increase the volume by adding a variety of modules to support a plurality of content at the same time.

In order to achieve the above object, an apparatus according to the present invention comprises: a tuner unit for receiving and demodulating analog broadcast signals and digital broadcast signals; A dual channel MPEG encoder for encoding an analog video signal and an analog audio signal output from the tuner unit into an MPEG2 transport stream (a); A demux for demultiplexing the MPEG2 transport stream (a) output from the dual channel MPEG encoder and the MPEG2 transport stream (b) output from the tuner unit to output predetermined video information and audio information in MPEG2 format; And an MPEG decoder which decodes predetermined video information and audio information output from the demux and outputs the video and audio in a form that can be sensed by a user. The tuner unit includes: a first tuner in charge of the analog broadcast signal; And a second demodulator and a second demodulator in charge of the digital broadcast signal, wherein the plurality of tuners and demodulators are integrally included in the tuner unit.

In the case where the MPEG2 transport stream (b) is encrypted, it is preferable to further include a media reader for decrypting the MPEG2 transport stream (b) by a predetermined condition.

When the input signal is a terrestrial broadcast signal or a cable broadcast signal, the plurality of tuners may synchronize up to 1 GHz. When the input signal is a satellite broadcast signal, the plurality of tuners may be synchronized with the LNB-related power supply terminal from 1 GHz to 2 GHz.

In addition, it is preferable to configure a demodulation circuit modified according to the modulation method of the first demodulator input analog signal, and the second demodulator is preferably designed in a quadrature phase shift keying (QPSK) method when the input signal is a satellite broadcast signal. The second demodulator may be designed using a quadrature amplitude modulation (QAM) method when the input signal is a cable broadcast signal.

On the other hand, it is preferable that the plurality of tuners extract the input signal as a signal of the required frequency band only by using the SAW filter.

The analog video signal output from the tuner unit is a CVBS signal, and the analog audio signal output from the tuner unit is preferably an SIF signal.

Also, the MPEG2 transport stream (b) preferably contains multiple programs.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention, and methods of achieving the same will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention, and the general knowledge in the art to which the present invention pertains. It is provided to fully appreciate the scope of the invention to those skilled in the art, and the invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Figure 2 shows the structure of a set-top box according to the present invention. First, the broadcast signal 200 input through cable, terrestrial or satellite communication is converted into an intermediate frequency IF by an RF front end 201. The signal includes a digital / analog common use tuner (300), an out-of-band receiver (104) and a data-over-cable (DOCSIS) that can process both digital and analog broadcast signals. Service Interface Specification) is received by the receiver 105, respectively. The digital / analog tuner unit 300 is a device capable of receiving, for example, a digital broadcast signal by an ATSC (Advanced Television Systems Committee) type cable or an analog broadcast signal by a general airwave. A detailed description of the tuner unit 300 will be given later with reference to FIGS. 3 and 4.

Meanwhile, each analog video signal input to the digital / analog tuner unit 300 is output in CVBS format, and each analog audio signal is output in SIF format. In addition, each digital video and audio signal input to the digital / analog tuner unit 300 is output to the MPEG2 TS format including a multi-program or a single program after channel selection. do. Meanwhile, a signal input to the OOB receiver 104 is output as a quadrature phase shift keying (QPSK) signal after channel selection, and a signal input to the DOCSIS receiver 105 is a quadrature amplitude modulation (QAM) signal after channel tuning. Is output.

Each analog video signal CVBS output from the digital / analog tuner unit 300 is input to an analog video signal decoder 107 and output in an itu-trbt656 format. Each analog audio signal SIF output from the digital / analog tuner unit 300 is input to the MTS decoder (Multi-Channel Television Sound Decoder) 108, decoded, and then output as analog voice. This analog output voice is inputted to an analog-to-digital converter (109) again and converted into a digital signal.

On the other hand, the MPEG2 TS (Transport Stream) including multiple programs or single programs, output from the digital / analog tuner unit 300, may be transferred to a media cipher 115 corresponding to a conditional access unit. After the input is decrypted (Decryption), it is output to the demuxer (116). The TS input to the demux 116 is de-multiplexed into an MPEG2 elementary stream having one or more pieces of video information and one or more pieces of video information, and then the MPEG decoder (PCI BUS 120). MPEG Decoder 123.

On the other hand, each of the itu-trbt656 output from the analog video signal decoder 107 and the respective digital audio output from the A / D converter 109 are connected to a dual channel MPEG encoder 119. After being input and encoded into the MPEG2 TS, it is input to the demux 116 and demultiplexed like the TS output from the tuner 300, and then input to the MPEG decoder 123 through the PCI bus.

The MPEG decoder 123 serves to process several MPEG2 TSs simultaneously. The video information and audio information input to the MPEG decoder 123 are decoded, respectively, and output in the form of video and audio that can be detected by a user from the MPEG decoder 123.

3 schematically shows a structure of the tuner unit 300 according to the present invention. The tuner 300 has both an input terminal 301 that can accept an analog broadcast signal and an input terminal 302 that can accept a digital broadcast signal. An analog tuner 310 capable of receiving and tuning an analog broadcast signal through the analog input terminal 301, and an analog demodulator 322 capable of demodulating the tuned analog broadcast signal. And a digital tuner 330 capable of receiving and tuning digital broadcast signals through the digital input terminal 302, and a digital demodulating demodulated digital broadcast signals. Demodulator 340 is configured.

The analog tuner 310 and the digital tuner 330 should be able to select up to 1GHz when the input signal is a terrestrial wave or a cable, and should be able to synchronize from 1GHz to 2GHz with an LNB-related power stage when receiving a satellite signal. In addition, the analog demodulator 320 configures a demodulation circuit changed according to the modulation scheme of the input analog signal. In the case of the digital demodulator 340, a satellite is designed by quadrature phase shift keying (QPSK), a cable input is designed by a quadrature amplitude modulation (QAM) method, and an ATSC method by a ground file. to be.

4 is a block diagram showing in detail the tuner 300 according to the present invention.

First, when an analog broadcast signal is received by an antenna through the air, the received signal is amplified by a low noise amplifier (LNA) 311. The signal amplified through the LNA passes through the pin diode circuit 312 and is input to the tuning control module 313. The signal input to the tuning control module 313 is processed after passing through one or more SAW filters (Surface Acoustic Wave Filter) is converted into an intermediate frequency (IF) signal and output. The tuning control module 313 performs a function of controlling other modules required in the tuning circuit. For example, the tuning control module 313 may be implemented as a “MT2111” model. The SAW filter refers to a module that passes only necessary frequency components of a signal transmitted and received by a wireless communication device.

The IF signal output from the analog tuner 310 is input to the analog demodulator 320 and separated into an audio signal and a video signal, and then passed through SAW filters 321 and 322 to select only a predetermined frequency component to control analog demodulation. Input to module 324. The signal input to the analog demodulation control module 324 passes through a filter 323 and a voltage controlled oscillator (VCO) 325 performing a predetermined function, and then audio is output as an SIF signal, and an image is a band. After passing through the stop filter 326 and the predetermined amplifier 327, it is output as a CVBS (Composite video) signal. The voltage controlled oscillator 325 is a device that can output a desired oscillation frequency with a voltage applied from the outside.

Meanwhile, when the digital broadcast signal is received by the antenna, the received signal is amplified through the LNA 331. The signal amplified through the LNA passes through the pin diode circuit 332 and is input to the tuning control module 333. The signal input to the tuning control module 333 is processed after one or more SAW filters (Surface Acoustic Wave Filter) is converted into an IF signal and output. The tuning control module 333 performs a function of controlling other modules required by the tuning circuit. Like the analog tuning unit 310, the tuning control module 333 may be implemented as a “MT2111” model.

The IF signal output from the digital tuner 330 is input to the variable amplifier 341 of the digital demodulator 340. The signal amplified by the variable amplifier 341 is filtered through the SAW filter 342, and then input to the digital demodulation control module 345 through the predetermined amplifier 343. The digital demodulation control module 345 performs a function of extracting a transport stream by controlling other modules required by the demodulation circuit, and may be implemented in a model such as "Nxt2002". The transport stream output from the digital demodulation control module 345 may contain a single program or a plurality of programs. Some IF signals output from the digital demodulation control module 345 are fed back to the variable amplifier 341 to adjust the gain of the variable amplifier 341 to a predetermined magnitude.

Meanwhile, the analog AGC (Auto Gain Control) signal partially extracted from the analog demodulation control module 324 and the digital AGC signal output from the tuning control module 333 and passed through the AGC detector 351 are the AGC switch 350. ) Is entered. When the AGC switch 350 switches and outputs the analog AGC signal and the digital AGC signal, the output signals are respectively supplied to the tuning control module 313 of the analog tuner 310 or the digital tuner 330 according to the type thereof. It is fed back to the tuning control module 333 and input. In addition, the signal passing through the AGC switch 350 may be transmitted to an external device through IEEE 1394 or the like in the form of AGC TP data via a predetermined amplifier 352.

Although embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

According to the present invention, the market competitiveness due to the improvement of the function of the set-top box is enhanced. And, when the same function is required, there is a significant cost reduction effect.

In addition, according to the present invention, it is possible to reduce the size of the set-top box, it is possible to reduce the heat generated by reducing the power consumption of the product. Therefore, it is possible to improve the reliability of the product by delaying the aging phenomenon.

1 is a block diagram schematically showing the structure of a digital / analog tuner of a conventional set-top box;

2 is a block diagram showing the structure of a set-top box according to the present invention.

3 is a block diagram schematically showing a structure for a digital / analog tuner unit according to the present invention;

Figure 4 is a block diagram showing in detail the structure for the digital / analog tuner unit according to the present invention.

(Explanation of symbols for the main parts of the drawing)

200: broadcast signal 201: RF front end

115: media reader 116: demux

119: dual channel MPEG encoder 120: PCI bus

123: MPEG decoder 300: digital / analog tuner unit

310: analog demodulator 320: analog demodulator

330: digital demodulator 340: digital demodulator

311, 331: LNA 313, 333: Sync Control Module

314, 315, 321, 322, 334, 335, 342: SAW filter

324: analog demodulation control module 345: digital demodulation control module

Claims (9)

A tuner unit for receiving and demodulating analog broadcast signals and digital broadcast signals; A dual channel MPEG encoder for encoding the analog video signal and the analog audio signal output from the tuner unit into an MPEG2 transport stream (a); A demux for demultiplexing the MPEG2 transport stream (a) output from the dual channel MPEG encoder and the MPEG2 transport stream (b) output from the tuner unit to output predetermined video information and audio information in MPEG2 format; It includes an MPEG decoder for decoding the predetermined video information and audio information output from the demux and output in the form of video and audio that can be detected by the user, The tuner unit includes a first tuner and a first demodulator in charge of the analog broadcast signal, and a second tuner and a second demodulator in charge of the digital broadcast signal, wherein the plurality of tuners and the demodulator are included in the tuner unit. A device capable of simultaneously receiving digital broadcasts and analog broadcasts, characterized in that it is integrally included. 2. The digital broadcasting and analog broadcasting according to claim 1, further comprising a media reader for deciphering the MPEG2 transport stream b under predetermined conditions when the MPEG2 transport stream b is encrypted. Devices that can receive both at the same time. 2. The apparatus of claim 1, wherein the plurality of tuners can synchronize up to 1 GHz when the input signal is a terrestrial broadcast signal or a cable broadcast signal. A device capable of receiving digital broadcasts and analog broadcasts simultaneously. The apparatus as claimed in claim 1, wherein the demodulation circuit is adapted to be modified according to a modulation scheme of the analog signal input to the first demodulator. The apparatus of claim 1, wherein the second demodulator is designed in a quadrature phase shift keying (QPSK) scheme when the input signal is a satellite broadcast signal. The apparatus of claim 1, wherein the second demodulator is designed in a quadrature amplitude modulation (QAM) scheme when the input signal is a cable broadcast signal. The apparatus of claim 1, wherein the plurality of tuners extract the input signal as a signal having a required frequency band using a SAW filter. The apparatus of claim 1, wherein the analog video signal output from the tuner unit is a CVBS signal, and the analog audio signal output from the tuner unit is a SIF signal. 2. The apparatus of claim 1, wherein the MPEG2 transport stream (b) comprises multiple programs.