EP2345242A2

EP2345242A2 - Transmitting and receiving method and device of providing conditional access broadcasting services

Info

Publication number: EP2345242A2
Application number: EP09819318A
Authority: EP
Inventors: Byungjun Bae; Joungil Yun; Jong Soo Lim; Soo In Lee
Original assignee: Electronics and Telecommunications Research Institute ETRI
Current assignee: Electronics and Telecommunications Research Institute ETRI
Priority date: 2008-10-07
Filing date: 2009-07-08
Publication date: 2011-07-20
Also published as: KR20100039117A; WO2010041811A2; EP2345242A4; KR100972029B1; WO2010041811A3

Abstract

Provided is a transmitting/receiving method and device for providing a conditional access broadcasting service. A transmitting method for providing a conditional access broadcasting service includes generating a control word (SI 10) for scrambling by- encoding a conditional access subscriber's, and changing the encoded data into an entitlement control message and an entitlement management message including the data generated by classifying the conditional access subscriber and a non-subscriber by activating the data (S120). Also, the method includes generating a final stream by multiplexing (S130) the entitlement control message, the entitlement management message, and a base stream for a first broadcasting service (SI 40), generating a base layer frame and an enhancement layer frame (SI 50) based on the final stream and an enhancement layer stream for a second broadcasting service, generating a broadcasting signal by hierarchically modulating (SI 60) the base layer frame and the enhancement layer frame, and transmitting the broadcasting signal.

Description

TRANSMITTING AND RECEIVING METHOD AND DEVICE OF PROVIDING CONDITIONAL ACCESS BROADCASTING SERVICES

The present invention relates to a transmitting/receiving method and device for providing a conditional access broadcasting service. Particularly, the present invention relates to a transmitting/receiving method and device for providing a layered conditional access broadcasting service through advanced terrestrial digital multimedia broadcasting (T-DMB).

The terrestrial digital multimedia broadcasting (T-DMB) represents a broadcasting system that is generated by adding a multimedia broadcasting service including a video service to the European Eureka 147-based digital audio broadcasting (DAB) system.

The advanced terrestrial digital multimedia broadcasting (AT-DMB) represents a broadcasting system having extended the capability of transmission data to be double the maximum by adding a new layered modulation method to the T-DMB. The AT-DMB uses the same frequency bandwidth as the existing T-DMB and increases the transmission capability to be double the maximum to provide further services and also supply the standard definition (SD) video service that is four times the T-DMB image quality.

In order to activate the T-DMB market, discussion about charging for the T-DMB data broadcasting service has recently increased. To provide such a charged service, the conditional access system (CAS) is applied to the corresponding contents. In the case of the AT-DMB allowing provision of many further broadcasting services compared to the T-DMB, it is needed to consider applying the charged service to the conditional access system.

That is, the AT-DMB system that is a little different from the T-DMB system requires a method for applying a conditional access system for providing charged services.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

The present invention has been made in an effort to provide a transmitting/receiving method and device for providing a conditional access broadcasting service for a charged service that is compatible with the existing T-DMB by using the AT-DMB network.

An exemplary embodiment of the present invention provides a transmitting method for providing a conditional access broadcasting service including: generating a control word for scrambling by encoding a conditional access subscriber's data; changing the encoded data into an entitlement control message and an entitlement management message including data having classified a conditional access subscriber and a non-subscriber acquired by activating the encoded data; generating a final stream by multiplexing a base layer stream for a first broadcasting service, the entitlement control message, and the entitlement management message; generating a base layer frame and an enchancement layer frame based on the final stream and an enchancement layer stream for a second broadcasting service; and generating a broadcasting signal by hierarchically modulating the base layer frame and the enchancement layer frame and transmitting the same.

Another embodiment of the present invention provides a transmitting device for providing a conditional access broadcasting service including: an encoder for generating a control word for scrambling by encoding a conditional access subscriber's data, and changing the encoded data into an entitlement control message and an entitlement management message; a first multiplexer for generating a final stream by multiplexing the entitlement control message, the entitlement management message, and a base layer stream; a second multiplexer for multiplexing the final stream and the enchancement layer stream; and a modulator for hierarchically modulating a result of the second multiplexer.

Yet another embodiment of the present invention provides a receiving method for providing a conditional access broadcasting service including: generating a base layer ensemble corresponding to a first broadcasting service and an enchancement layer ensemble corresponding to a second broadcasting service by hierarchically demodulating a received broadcasting signal; generating a final stream and a scrambled enchancement layer stream by demultiplexing the base layer ensemble and the enchancement layer ensemble; generating an entitlement control message, an entitlement management message, and a scrambled base layer stream by demultiplexing the final stream; generating a control word for descrambling by decoding the entitlement control message and the entitlement management message; descrambling the scrambled base layer stream and the scrambled enchancement layer stream by using the control word; and decoding the descrambled base layer stream and enchancement layer stream and displaying the decoded results.

According to an embodiment of the present invention, a receiving device for providing a conditional access broadcasting service includes: a demodulator for generating a base layer ensemble corresponding to a first broadcasting service and an enchancement layer ensemble corresponding to a second broadcasting service by hierarchically demodulating a broadcasting signal; a demultiplexer for generating a final stream and a scrambled enchancement layer stream by demultiplexing the base layer ensemble and enchancement layer ensemble, and generating an entitlement control message, an entitlement management message, and a scrambled base layer stream by demultiplexing the final stream; a first decoder for generating a control word for descrambling by decoding the entitlement control message and the entitlement management message; a first descrambler for descrambling the base layer stream by using the control word; a second descrambler for descrambling the scrambled enchancement layer stream by using the control word; and a second decoder for decoding the descrambled base layer stream and the enchancement layer stream.

According to the exemplary embodiment of the present invention, the charged service can be provided by using the AT-DMB network. Also, as the charged service is provided, associated business such as a business for providing data information including video, news, and location can be revived, and better quality services can be provided to viewers.

FIG. 1 shows a block diagram for an AT-DMB transmitting system according to an exemplary embodiment of the present invention.

FIG. 2 shows a block diagram of a transmitting device for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention.

FIG. 3 shows a flowchart of a transmitting method for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention.

FIG. 4 shows a block diagram of a receiving device for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention.

FIG. 5 shows a flowchart of a receiving method for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention.

In the following detailed description, only certain exemplary embodiments of the present invention have been shown and described, simply by way of illustration. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification.

Throughout the specification, unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising" will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

Hereinafter, a transmitting/receiving method and device for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a block diagram of a general advanced terrestrial digital multimedia broadcasting (AT-DMB) transmitting system.

As shown in FIG. 1, the AT-DMB transmitting system includes an AT-DMB ensemble multiplexer 10 and an AT-DMB modulator 20.

The AT-DMB ensemble multiplexer 10 receives contents including a plurality of ensemble transport interface (ETI) frames or various interfaces from a plurality of encoders and multiplexers (not shown), and multiplexes the received contents to generate two ETI frames. Here, the two ETI frames includes a base layer ETI frame that is the existing T-DMB ETI frame and an enchancement layer ETI frame that is a hierarchical modulating ETI frame for increasing transmission capability. An enchancement layer according to an exemplary embodiment of the present invention can be an improved area, but is not limited thereto.

Also, in the AT-DMB, the existing T-DMB service is referred to as a base layer service or a first broadcasting service, and the hierarchically modulated service is called an enchancement layer service, an improved area service, or a second broadcasting service.

The AT-DMB modulator 20 generates a broadcasting signal by hierarchically modulating the received base layer ETI frame and the enchancement layer ETI frame. That is, the AT-DMB modulator 20 generates a broadcasting signal by hierarchically modulating the existing T-DMB ETI frame and the ETI frame.

The AT-DMB system according to an exemplary embodiment of the present invention is compatible with the existing T-DMB broadcasting. Therefore, the AT-DMB system that is a little different from the existing T-DMB system can provide a charged service by applying the conditional access system (CAS).

The conditional access system (CAS) changes the original broadcasting signal and transmits it so that the user may normally view the broadcasting program through a receiver having a receiving right for the corresponding broadcasting program. Therefore, it is possible to provide a charged broadcasting service in which a receiver with the receiving right on a specific broadcasting program views the same by using the conditional access system, and in this instance, the receiver with the receiving right can view the corresponding broadcasting program. The format of the original broadcasting signal corresponding to the broadcasting program is changed and transmitted so that an unregistered receiver with no receiving right may not view the corresponding broadcasting program, which is called encryption or scrambling. A key used for the scrambling process is called a control word (CW).

The exemplary embodiment of the present invention has realized a transmitting/receiving method and device for providing a conditional access broadcasting service for efficiently applying the conditional access system in the AT-DMB system.

Next, a transmitting/receiving method and device for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention will be described with reference to FIG. 2 to FIG. 5.

First, the transmitting device for providing a conditional access broadcasting service receives a conditional access message from an external data management server (not shown) including conditional access subscriber data.

As shown in FIG. 2, the transmitting device includes an encoder 110, a first scrambler 120, a second scrambler 130, a moving picture expert group (MPEG)-2 multiplexer 140, and ensemble multiplexer 150, and a modulator 160.

The encoder 110 generates an encryption key that is a control word used for scrambling by encoding input conditional access subscriber's data. Also, the encoder 110 changes the encoded conditional access subscriber's data into an entitlement control message (ECM) and an entitlement management message (EMM), and transmits them to the MPEG-2 multiplexer 140. Here, the ECM includes scrambled contents, for example scrambled video stream and a control word for scrambling, and the EMM activates the subscriber's data to make the data having classified the conditional access subscriber and the conditional access non-subscriber into a message.

The first scrambler 120 encrypts (i.e., scrambles) the base layer stream input by using the control word received from the encoder 110. Here, the base layer stream is input through the base layer. In this instance, the base layer stream corresponds to the contents input through the base layer for the T-DMB. Also, the base layer stream may not be scrambled according to the user's selection.

Next, the first scrambler 120 transmits the scrambled base layer stream to the MPEG-2 multiplexer 140.

The second scrambler 130 scrambles the enchancement layer stream input by using the control word generated by the encoder 110, that is, the same control word input to the base layer, and transmits the scrambled enchancement layer stream to the ensemble multiplexer 150. Here, the enchancement layer stream corresponds to the contents input through the enchancement layer for the AT-DMB.

The MPEG-2 multiplexer 140 multiplexes the received ECM, EMM, and scrambled base layer stream to generate a final stream. When the final stream is transmitted to the ensemble multiplexer 150, the transport format includes the format of the ETI frame or MPEG-2 transport stream (TS).

The ensemble multiplexer 150 generates a base layer ETI frame and an enchancement layer ETI frame by multiplexing the ETI or TS format final stream generated by the MPEG-2 multiplexer 140, the scrambled enchancement layer stream, contents for other various services, and a fast information channel (FIC) for showing service configuration information. In detail, the ensemble multiplexer 150 generates a base layer ETI frame by multiplexing the final stream, contents, and FIC, and generates an enchancement layer ETI frame by multiplexing the scrambled enchancement layer stream, contents, and FIC.

The modulator 160 generates an AT-DMB broadcasting signal by hierarchically modulating the base layer ETI frame and the enchancement layer ETI frame received from the ensemble multiplexer 150. Here, the generated AT-DMB broadcasting signal is provided to the subscribers, and the conditional access subscribers having subscribed to the charged service from among the subscribers can watch the broadcasting program through the AT-DMB broadcasting signal because of the ECM and EMM included in the AT-DMB broadcasting signal. The conditional access subscriber represents a subscriber who subscribes to a charged service for paying a predetermined amount of money in order to receive a specific broadcasting program.

Next, a transmitting method for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention will be described in detail with reference to FIG. 3.

First, the transmitting device generates a control word by encoding the data of the conditional access subscriber received from the outside (S110). Also, the transmitting device changes the encoded data of the conditional access subscriber into the ECM and EMM.

The transmitting device scrambles the base layer stream by using the generated control word (S120). The transmitting device generates a final stream in the format of the ETI frame or the MPEG-2 transport stream by multiplexing the scrambled base layer stream, the ECM, and the EMM (S130).

Also, the transmitting device scrambles the enchancement layer stream by using the generated control word (S140).

Next, the transmitting device generates a base layer ETI frame and an enchancement layer ETI frame by selectively multiplexing the generated final stream, the scrambled enchancement layer stream, other service contents, and the FIC (S150).

The transmitting device generates an AT-DMB broadcasting signal and transmits it by hierarchically modulating the generated base layer ETI frame and the enchancement layer ETI frame. Accordingly, the conditional access subscriber having requested the charged service through the AT-DMB broadcasting signal receives the AT-DMB service (S160). Here, the conditional access subscriber receives the AT-DMB service by using the EMM that is generated into a message by classifying the conditional access subscriber and other subscribers included in the AT-DMB broadcasting signal.

A receiving device for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention will now be described with reference to FIG. 4.

As shown in FIG. 4, the receiving device includes a demodulator 210, an ensemble demultiplexer 220, a fast information channel (FIC) analyzer 230, a first descrambler 240, a first decoder 250, a second descrambler 260, a second decoder 270, and a display 280.

The demodulator 210 generates a base layer ensemble and an enchancement layer ensemble by hierarchically demodulating the AT-DMB broadcasting signal received from the transmitting device.

The ensemble demultiplexer 220 generates a final stream, a scrambled enchancement layer stream, various other services, contents, and FIC by demultiplexing the received base layer ensemble and the enchancement layer ensemble. Also, the ensemble demultiplexer 220 generates an ECM, an EMM, and a scrambled base layer stream by demultiplexing the generated final stream.

The FIC analyzer 230 detects a scrambled stream from the final stream by analyzing the FIC by demultiplexing the base layer ensemble.

The first descrambler 240 descrambles the scrambled base layer stream received from the ensemble demultiplexer 220 by using the control word for descrambling received from the first decoder 250.

The first decoder 250 changes the generated ECM and EMM into the conditional access subscriber's data. The first decoder 250 generates a control word for descrambling by decoding the acquired conditional access subscriber's data.

The second descrambler 260 descrambles the scrambled enchancement layer stream provided by the ensemble demultiplexer 220 by using the control word for descrambling provided by the first decoder 250.

The second decoder 270 generates a corresponding video image by decoding the scrambled stream from the stream, the descrambled base layer stream, and the enchancement layer stream. The generated video image includes the standard definition (SD)-level image. Here, the video image is provided to the conditional access subscriber through the EMM that is generated as a message by classifying the conditional access subscriber and the subscriber other than the conditional access subscriber.

The display 280 displays the generated video image. Here, when the display 280 provides the AT-DMB SD-level video image service, the second decoder 270 can use a scalable video coding (SVC) decoder, but is not limited thereto.

A receiving method for providing a conditional access broadcasting service according to an exemplary embodiment of the present invention will now be described with reference to FIG. 5.

First, the receiving device generates a base layer ensemble and an enchancement layer ensemble by hierarchically demodulating the AT-DMB broadcasting signal received from the transmitting device S210.

The receiving device generates a final stream, a scrambled enchancement layer stream, contents for various other services, and FIC by demultiplexing the generated base layer ensemble and the enchancement layer ensemble (S220). Also, the receiving device generates an ECM, an EMM, and a scrambled base layer stream by demultiplexing the final stream.

The receiving device extracts a scrambled stream from the final stream by analyzing the FIC generated by demultiplexing the base layer ensemble (S230).

The receiving device changes the ECM and the EMM into the conditional access subscriber's data. The receiving device decodes the conditional access subscriber's data to generate a control word for descrambling (S240).

The receiving device descrambles the base layer stream by using the generated control word for descrambling (S250). Also, the receiving device descrambles the scrambled enchancement layer stream by using the generated control word for descrambling (S260).

The receiving device displays the AT-DMB video image generated by decoding the scrambled stream, the descrambled base layer stream, and the enchancement layer stream (S270).

Accordingly, the receiving method for providing the conditional access broadcasting service can provide the conditional access broadcasting service for providing the charged service that is compatible with the T-DMB in the AT-DMB network to the conditional access subscriber.

The above-described embodiments can be realized through a program for realizing functions corresponding to the configuration of the embodiments or a recording medium for recording the program in addition to through the above-described device and/or method, which is easily realized by a person skilled in the art.

While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

A transmitting method for providing a conditional access broadcasting service, comprising:

generating a control word for scrambling by encoding a conditional access subscriber's data;

changing the encoded data into an entitlement control message and an entitlement management message including data having classified a conditional access subscriber and a non-subscriber acquired by activating the encoded data;

generating a final stream by multiplexing a base layer stream for a first broadcasting service, the entitlement control message, and the entitlement management message;

generating a base layer frame and an enchancement layer frame based on the final stream and an enchancement layer stream for a second broadcasting service; and

generating a broadcasting signal by hierarchically modulating the base layer frame and the enchancement layer frame and transmitting the same.
The transmitting method of claim 1, wherein

the broadcasting signal is provided to a corresponding conditional access subscriber according to the entitlement management message.
The transmitting method of claim 1, wherein

the generating of a final stream includes scrambling the base layer stream by using the control word, and

the generating of a base layer frame and an enchancement layer frame includes scrambling the enchancement layer stream by using the control word.
The transmitting method of claim 3, wherein

the generating of a base layer frame and an enchancement layer frame includes:

generating the base layer frame by multiplexing the final stream, contents to be provided, and a fast information channel showing structure information on the provided service; and

generating an enchancement layer frame by multiplexing the scrambled enchancement layer stream, the contents, and the fast information channel.
The transmitting method of claim 1, wherein

the final stream is generated in a transport format of one of an ensemble transport interface frame and a transport stream.
A transmitting device for providing a conditional access broadcasting service, comprising:

an encoder for generating a control word for scrambling by encoding a conditional access subscriber's data, and changing the encoded data into an entitlement control message and an entitlement management message;

a first multiplexer for generating a final stream by multiplexing the entitlement control message, the entitlement management message, and a base layer stream;

a second multiplexer for multiplexing the final stream and the enchancement layer stream; and

a modulator for hierarchically modulating a result of the second multiplexer.
The transmitting device of claim 6, further including:

a first scrambler for scrambling the base layer stream by using the control word, and providing the scrambled base layer stream to the first multiplexer; and

a second scrambler for scrambling the enchancement layer stream by using the control word, and providing the scrambled enchancement layer stream to the second multiplexer.
The transmitting device of claim 6, wherein

the first multiplexer multiplexes the base layer stream for the first broadcasting service, and

the second multiplexer generates a base layer frame and an enchancement layer frame by multiplexing an enchancement layer stream for the second broadcasting service and the final stream.
The transmitting device of claim 8, wherein

the modulator

generates a broadcasting signal by hierarchically modulating the base layer frame and the enchancement layer frame, and provides the broadcasting signal to the corresponding conditional access subscriber by using the entitlement management message.
A receiving method for providing a conditional access broadcasting service, comprising:

generating a base layer ensemble corresponding to a first broadcasting service and an enchancement layer ensemble corresponding to a second broadcasting service by hierarchically demodulating a received broadcasting signal;

generating a final stream and a scrambled enchancement layer stream by demultiplexing the base layer ensemble and the enchancement layer ensemble;

generating an entitlement control message, an entitlement management message, and a scrambled base layer stream by demultiplexing the final stream;

generating a control word for descrambling by decoding the entitlement control message and the entitlement management message;

descrambling the scrambled base layer stream and the scrambled enchancement layer stream by using the control word; and

decoding the descrambled base layer stream and enchancement layer stream and displaying the decoded results.
The receiving method of claim 10, wherein

the descrambling of an enchancement layer stream further includes

descrambling the base layer stream by using the control word.
A receiving device for providing a conditional access broadcasting service, comprising:

a demodulator for generating a base layer ensemble corresponding to a first broadcasting service and an enchancement layer ensemble corresponding to a second broadcasting service by hierarchically demodulating a broadcasting signal;

a demultiplexer for generating a final stream and a scrambled enchancement layer stream by demultiplexing the base layer ensemble and enchancement layer ensemble, and generating an entitlement control message, an entitlement management message, and a scrambled base layer stream by demultiplexing the final stream;

a first decoder for generating a control word for descrambling by decoding the entitlement control message and the entitlement management message;

a first descrambler for descrambling the base layer stream by using the control word;

a second descrambler for descrambling the scrambled enchancement layer stream by using the control word; and

a second decoder for decoding the descrambled base layer stream and the enchancement layer stream.
The receiving device of claim 12, further including

a display for displaying a result of the second decoder.