KR20050023683A - Digital Contents Receiver System - Google Patents

Abstract

PURPOSE: A system for receiving digital contents is provided to enable a channel selected through a subscriber PC(Personal Computer) to be received and allow the subscriber PC to reproduce a digital broadcast of high quality by performing frequency band tuning in order to receive contents from a head end for transmitting RF(Radio Frequency) contents through a multiple frequency band. CONSTITUTION: A head end(H) includes a database for storing digital contents and transmits the digital contents to a subscriber PC(C). A DCR(Digital Contents Receiver)(100) receives RF contents from the head end via a transmission network and transmits them to the subscriber PC. This subscriber PC plays the digital contents transmitted from the DCR. A digital tuner(110) tunes a frequency band of the transmission network so as to receive RF contents of a corresponding channel and converts them into digital data. A USB(Universal Serial Bus) controller(120) provides interface with the subscriber PC so that the digital data can be transferred to the subscriber PC. A control part(130) controls the digital tuner and generates a control signal so that the received digital contents can be converted into a standard format by the USB controller.

Description

Digital Contents Receiving System {Digital Contents Receiver System}

The present invention has a database in which a plurality of digital contents are stored and receives radio frequency (RF) content from a headend transmitting a digital content selected by a subscriber to a subscriber PC on its own web page, and transmits it to the subscriber PC. A digital content receiver for reproducing.

A conventional digital content receiving system will be described with reference to FIGS. 1 and 2 as follows. Digital broadcasting can be classified into satellite broadcasting and cable broadcasting according to the receiving method. Especially, in order to receive cable broadcasting, a set-top box connected to a TV is required, and in order to receive digital contents through a general Internet network, it is connected to a computer. You need a cable modem.

First, a digital set-top box receives MPEG coded / multiplexed, QAM-modulated digital broadcast signal streams from a headend that provides digital broadcast services through a cable network, and receives the received broadcast signals through QAM decoding and MPEG decoding. Device to be displayed. Currently, Korea is pursuing digital cable broadcasting following digital satellite broadcasting, but it is still at an early stage.

In addition, the cable modem is a device connected to a PC to enable Internet access through a cable network. The cable modem is connected to a specific server providing a video content service to receive high-compression video data and display the same through a PC.

Currently, cable modem subscribers for Internet use are about 4 million, but data-oriented services are provided due to the limitations of the transmission bandwidth of the cable network. In the case of large data such as video data, it is necessary to transmit with a high compression ratio. As a result, high image quality was not possible.

1 is a diagram illustrating a frequency band used when transmitting data through a conventional cable network. The uplink band from the subscriber PC side to the server side is 5 to 42 MHz, and the downband from the server side to the subscriber PC side is 54 to 750 MHz. It has a very wide bandwidth compared to the upband. Among them, 54 to 450 MHz is a broadcasting station subscriber station signal band for cable TV.

Nevertheless, the actual downlink used for data transmission through the cable modem is only a specific band such as ① out of 54 to 750 MHz, and a single RF (Radiofrequency) channel is shared by subscribers per cell connected to the optical cable. Since data is transmitted, the actual data rate can only expect a data rate obtained by dividing the number of subscribers by 27 Mbps, which is a theoretical maximum data rate.

In addition, as shown in FIG. 2, in the conventional case, the headend 10 simultaneously transmits all kinds of data (text data, video / audio data, etc.) through the specific band to the subscriber modem M. There has been a problem that a transmission band for transmitting relatively large video content or a streaming service that is transmitted in real time is not sufficiently secured.

Due to the structural problems of the cable network, most real-time video content is compressed to a high compression rate and then transmitted to the subscriber PC 30 side, whereby the subscriber PC 30 side has to bear the deterioration of image quality.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object thereof is to receive a channel selected by a subscriber PC by performing frequency band tuning to receive content from a headend transmitting RF content in multiple frequency bands. It provides a DCR for demodulating the received data, and can play high-definition digital broadcasting on a PC as decoding and MPEG decoding are performed software by a media playback program running on a subscriber PC connected to the DCR. The present invention provides a digital content receiver and a system thereof.

According to a feature of the digital content receiving system according to the present invention for solving the above problems, a headend having a database in which a plurality of digital contents are stored and transmitting the digital content selected by the subscriber on its own web page to the subscriber PC, and a transmission network. A digital contents receiver (hereinafter referred to as a DCR) for receiving RF (Radio frequency) content from the headend and transmitting it to a subscriber PC, and a subscriber PC for playing digital content transmitted from the DCR. In the digital content receiving system, the DCR tunes a frequency band of a transmission network to receive RF content of a corresponding channel, and converts it into digital data, and digital data received from the digital tuner is transmitted to a subscriber PC. Interfacing with the subscriber PC for delivery. And a controller for controlling the frequency band tuning and demodulation by the digital tuner and for issuing a control signal to standard-convert the received digital content by the USB controller. do.

In addition, the operation method for the initial authentication of the digital content receiving system includes a first step in which the subscriber PC loads the unique ID of the DCR and transmits the ID to the headend according to the subscriber authentication request of the headend, and the ID of the DCR. It is determined whether the DCR ID of the valid subscriber is determined by the received headend, and if it is the valid subscriber, a second step of returning an authentication key to the subscriber PC, and comparing the authentication key received by the subscriber PC with the self-stored key, If so, the third step of initiating mutual interfacing to allow the DCR to receive content from the headend.

In addition, the method of operating the digital content receiving system according to the present invention after the authentication procedure includes a first step of selecting a content and a channel to be received on a web page driven by the headend, and receiving the selected content and the corresponding channel information to the subscriber PC. And a second step of delivering to the DCR, a third step of receiving the contents of the corresponding channel by the DCR tuning a frequency band based on the channel information, and transmitting the contents of the corresponding channel to the subscriber PC; And a fourth step of reading the compression scheme and performing the corresponding MPEG decoding, and then reproducing it.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. 3 is a diagram illustrating a connection state of the digital content receiver of the present invention, and FIG. 4 is a diagram illustrating a method of transmitting digital content transmitted to the digital content receiver of the present invention.

First, referring to FIG. 3, the connection state between the digital content receiver and the PC is as follows.

The digital content receiver 100 of the present invention is connected to a head end (H), which is a content provider, via a cable network, and can reproduce digital content transmitted from the head end, such as a PC (C) and a laptop. Connected to the medium.

In addition, the PC (C) is connected to the modem (M) to enable data transmission and reception through the Internet network, the user can access the web page driven by the headend through the PC (C), the web On the page, subscriber authentication, digital content selection, and transmission request can be made.

The headend (H) is a broadcast server device having a database storing digital broadcasting content for a real-time broadcasting service or AOD / VOD service, etc., which drives a web page for a subscriber to select login / content, and the web The transmission frequency band is multiplexed by allocating a predetermined frequency band for transmission of moving picture content on the subscriber PC side input on the page.

Herein, the digital content stored in the database includes not only IP packets for Internet services but also MPEG2, which is a general digital broadcasting format, and MPEG4, which is a video (audio including) file format based on the Internet.

Since the modem M uses the existing transmission band as it is, the plain text data is transmitted and received with the headend H by using the modem M, and the content data for digital broadcasting is determined by the transmission band of the modem M. Since a separate frequency band (DCR channel) is used, data transmission bottlenecks in a cable network can be solved. Such a video content transmission method according to the present invention is as shown in FIG.

FIG. 5 is a block diagram illustrating an internal configuration of a digital content receiver of the present invention, and FIG. 6 is a diagram illustrating a module configuration of a program for media playback interoperating with the digital content receiver of the present invention. The present invention will be described in more detail with reference to this.

The digital contents receiver 100 is a digital contents receiver for transmitting the received contents to the subscriber PC C by tuning a frequency band corresponding to the video contents transmitted from the headend H through a transmission network. Here, although the DCR 100 of the present embodiment is implemented as an independent device, it can be used as a digital content receiving card to be embedded in the PC (C).

The DCR 100 is a digital tuner 110 for tuning and receiving the transmission band of the video data transmitted through the cable network, and the video data tuned in the digital tuner is connected via a cable based on the USB 2.0 standard USB controller 120 for transmitting to the subscriber PC side, a control unit for performing a signal processing and control so that the appropriate band is tuned through the digital tuner, and the received video data is standard-converted by the USB controller 120 ( 130). Of course, at this time, the USB controller 120 is not limited to the 2.0 version can be used in the USB standard developed later.

The digital tuner 110 receives an RF content transmitted through a corresponding channel by tuning a channel number (ie, a frequency band) that a subscriber wants to receive among the RF content signals transmitted by the headend H, and digitally transmits the digital content. To perform the function.

In this case, a buffer 140 may be provided to temporarily store data in order to prevent data loss due to a transmission speed difference between the digital tuner 110 and the USB controller 120 that receive video data at 27 Mbytes per second. .

In addition, the DCR 100 may be equipped with an internal or external memory capable of directly storing the content transmitted from the headend (H).

That is, the DCR 100 is a device that tunes a channel selected by a subscriber to receive desired video content and displays it on the subscriber PC C. The DCR 100 extracts content data for digital broadcasting modulated at a specific frequency and Transfer to subscriber PC (C) via USB cable.

Since the moving picture data received by the DCR 100 configured as described above is transferred to the PC C, the PC C is decoded by the USB device driver for recognizing the DCR device and the moving picture data on the PC monitor. A program for media playback which is to be displayed is installed. A configuration diagram of the subscriber PC will be described with reference to FIG. 6 mainly on the media playback program.

The subscriber PC (C) recognizes the DCR (100) connected to the USB port through the USB device driver, and the data stream of the digital content transmitted from the DCR (100) through the USB controller (C12) connected to the USB port. Runs the installed media playback program for decoding and playback of the format.

At this time, the digital content transmitted from the DCR is in an MPEG compressed state or an uncompressed IP data format, and is decoded by MPEG decoding by the media player.

Therefore, the digital content delivered from the DCR 100 of the present invention is MPEG decoded in software by the media playback program of the PC C. If the MPEG2 or MPEG4 broadcast signal is used, the MPEG content is decoded. It is externally output via the video card C13 and the sound card C14, and in the case of an IP packet, it is reproduced without performing separate MPEG decoding.

In particular, for the protection of the digital content, the stream is encrypted in the transmission side, i.e., the head end (H) side, by software decryption by the media playback program.

In addition, the media playback program delivers the channel of the digital broadcast input by the subscriber and the control command for controlling each function to the DCR 100 to interface with the user so that proper channel tuning is performed. Of course, such a media playback program and each component interoperating with the program are controlled by the central control unit (CPU).

7 is a flowchart illustrating a signal flow transmitted and received to and from a subscriber side and the headend configured as a DCR and a subscriber PC according to the present invention, and FIG. 8 is a signal flow transmitted and received between a PC and a DCR according to the present invention. Flowchart. With reference to this, the operation method of the digital content receiver (DCR) 100 according to the present invention is as follows.

First, referring to FIG. 7, at the request of a subscriber to receive digital content from the headend, the headend initiates an authentication procedure of the DCR device.

The DCR is uniquely assigned to each device, and the subscriber PC loads the ID of the connected DCR according to the authentication request from the headend and transmits the ID to the headend (S1, S2).

The headend having received the ID of the DCR device (S3) searches the database (S4) and determines whether the ID is a valid subscriber (S5). If the subscriber is a valid subscriber, an authentication key is returned (S6), or the content transmission request to the subscriber is ignored (S7).

The subscriber PC receiving the authentication key compares the authentication key transmitted from the headend with a previously stored key (S8, S9). In order to receive the content (S10), if different, the authentication is rejected, and a message indicating that the interface between the DCR and the headend is not possible is output to the monitor (S11).

When the DCR authentication process is completed by the process of FIG. 7, the operation as shown in FIG. 8 continues, and a series of processes described below are performed by software by a media playback program driven on a PC. In this case, the media playback program is a dedicated application by the DCR provider.

Channel information for receiving the content selected by the subscriber on the web page driven by the headend is transmitted to the DCR through the subscriber PC. (L1) The DCR tunes a frequency band based on the channel information to provide desired content. Receive (L2, L3), and deliver it to the subscriber PC side (L4).

Upon receiving the multi-band content data from the DCR, the PC releases the encryption for content protection (L5, L6), reads the way the content is compressed, and performs the corresponding MPEG decoding (L7, L8). The content may be IP data compressed or uncompressed in MPEG2 or MPEG4 format.

The decoded content data is reproduced on the PC. (L9)

As described above, the digital content receiver according to the present invention has been described with reference to the illustrated drawings. However, the present invention is not limited by the embodiments and drawings disclosed herein, and the application by the person skilled in the art is within the scope of the technical idea. It is possible.

The digital content receiver of the present invention configured as described above can receive content for digital broadcasting transmitted through multi-band through a cable network in the future when establishing a digital cable broadcasting and play it on a PC. Demodulation and MPEG decoding can be handled in software by a dedicated media playback program running on a PC, thereby simplifying the hardware configuration of the DCR device and reducing the cost.

1 is a diagram showing a data transmission frequency band using a conventional cable modem;

2 is a diagram illustrating a method of transmitting digital content using a conventional cable modem;

3 is a view showing a connection state of the DCR of the present invention;

4 is a diagram showing a method of transmitting digital content using a DCR of the present invention;

5 is a block diagram of a DCR of the present invention;

6 is an internal processing diagram of a subscriber PC of the present invention;

7 is a signal flow diagram transmitted and received between a subscriber side and a headend of the present invention;

8 is a signal flowchart transmitted and received between the PC and the DCR of the present invention.

<Explanation of symbols on main parts of the drawings>

C: Subscriber PC H: Headend

100: digital content receiver (DCR) 110: digital tuner

120: USB controller 130: control unit

140: buffer

Claims (10)

A headend having a database in which a plurality of digital contents are stored and transmitting digital content selected by a subscriber on its own web page to a subscriber PC, and receiving RF (Radio frequency) content from the headend through a transmission network and transmitting the same to the subscriber PC. In the digital content receiving system comprising a digital contents receiver (hereinafter referred to as DCR) and a subscriber PC for playing digital content transmitted from the DCR, The DCR is a digital tuner for tuning the frequency band of the transmission network to receive the RF content of the channel, and converts it into digital data; A USB controller for interfacing with the subscriber PC so that the digital data received from the digital tuner is transferred to the subscriber PC; And a control unit for controlling the frequency band tuning and demodulation by the digital tuner and for issuing a control signal to standard-convert the received digital content by the USB controller. The method of claim 1, The transmission network is a digital content receiving system, characterized in that the cable network (HFC). The method of claim 1, The DCR has a digital content receiving system, characterized in that the buffer is temporarily stored in order to prevent data loss due to the transmission speed difference of the data transmitted and received between the digital tuner and the USB controller. The method of claim 1, The DCR is a digital content receiving system, characterized in that the built-in or external memory that can directly store the digital content received and converted by the digital tuner. The method of claim 1, The USB controller is a digital content receiving system, characterized in that based on the USB 2.0 standard. The method of claim 1, The DCR is a digital content receiving system, characterized in that the unique ID used for subscriber authentication by the headend. The method of claim 6, The subscriber PC is installed with a USB driver for device recognition of the DCR and a program for media playback to perform the MPEG decoding of the digital content and then play it. The method of claim 7, wherein The media playback program transmits the unique ID of the DCR to the headend so that the subscriber authentication process is performed, and if it is determined to be an effective subscriber, communication between the headend and the DCR is initiated. Receiving system. A headend having a database in which a plurality of digital contents are stored and transmitting digital content selected by a subscriber on its own web page to a subscriber PC, and receiving RF (Radio frequency) content from the headend through a transmission network and transmitting the same to the subscriber PC. In the digital content receiving system comprising a digital contents receiver (hereinafter referred to as DCR) and a subscriber PC for playing digital content transmitted from the DCR, A first step of the subscriber PC loading and transmitting the unique ID of the DCR to the headend according to the subscriber authentication request of the headend; A second step of determining whether a valid subscriber is a DCR ID by the headend receiving the ID of the DCR, and returning an authentication key to the subscriber PC if the valid subscriber is a valid subscriber; And a third step of initiating mutual interfacing so that the DCR can receive content from the headend if the authentication key received by the subscriber PC is compared with the self-stored key. Initial operation of. A headend having a database in which a plurality of digital contents are stored and transmitting digital content selected by a subscriber on its own web page to a subscriber PC, and receiving RF (Radio frequency) content from the headend through a transmission network and transmitting the same to the subscriber PC. In the digital content receiving system comprising a digital contents receiver (hereinafter referred to as DCR) and a subscriber PC for playing digital content transmitted from the DCR, Selecting a content and a channel to be received on a web page driven by the headend; A second step of receiving the selected content and corresponding channel information to the subscriber PC and transmitting the same to the DCR; A third step of receiving, by a DCR, a frequency band based on the channel information, contents of a corresponding channel, and delivering the contents to a subscriber PC; And a fourth step in which the subscriber PC reads the compression scheme of the contents, performs the corresponding MPEG decoding, and then reproduces the contents.