KR20070097230A - Broadcasting receiver and receiving method - Google Patents

Abstract

An apparatus and a method for receiving broadcast are provided to recover broadcast transmitted in a conditional access state into original broadcast having no conditional access. An apparatus for receiving broadcast includes an interface and a host(100). The interface includes a physical layer and at least one protocol layer. The host receives a mobile broadcast service to perform description and decoding functions. The apparatus for receiving broadcast includes at least one module(150) detachable from a host. The module includes a card having information about the description of the host and a memory including a card administration program. The host receives a card administration program from a memory in the module to control the operation of a card if the insertion of the module is detected.

Description

Broadcasting receiver and receiving method

1 is a diagram showing an embodiment of a general digital multimedia broadcasting service structure

2 is a schematic diagram of a broadcast receiver capable of receiving mobile broadcast according to an embodiment of the present invention;

3 is a flowchart illustrating an embodiment of a method for receiving a reception restricted mobile broadcast according to the present invention.

4 is a schematic diagram of a broadcast receiver capable of receiving mobile broadcast according to another embodiment of the present invention;

Explanation of symbols for main parts of the drawings

100: host 101: control unit

102: data input unit 103: first memory

104: second memory 105: smart card interface

106: Decryptor 107: Decoder

108: output unit

150: module 151: smart card

152: external memory

The present invention relates to a broadcast receiver, and more particularly, to a broadcast receiver and a receiving method capable of receiving a mobile broadcast.

Digitalization of broadcasting is progressing rapidly through existing media such as terrestrial, satellite, and cable broadcasting, and is revolutionizing the environment of the broadcasting industry. Due to such environmental changes, a newly emerged medium is a broadcast receiver capable of receiving mobile broadcast.

There may be various broadcast receivers capable of receiving the mobile broadcast. For example, there are terminals such as digital multimedia broadcasting (DMB), digital video broadcasting-handheld (DVB-H), and media flow. In addition, the broadcast receiver applies a broadcast reception function to a personal portable terminal such as a mobile phone, a PDA, a notebook computer, a vehicle terminal, and provides various multimedia broadcasts to a user while moving or in a fixed place.

In particular, terrestrial digital multimedia broadcasting (DMB) has evolved from listening to watching and listening to broadcasting. The terrestrial DMB is based on Eureka-147 Digital Audio Broadcasting (DAB), which has been adopted as the European terrestrial radio standard. Added to improve multimedia broadcasting performance, RS codes (Reed-Solomon Code) and convolutional interleaver that are robust against burst errors that may occur on a transmission channel are added. The two additional blocks are applied to the DAB Ensemble input signal at the transmitter and provide an error rate low enough for video service even in a mobile receiving environment.

In addition, the transmission channel of the DMB broadcast is a wireless mobile reception channel, and the amplitude of the received signal is not only time-varying, but also the Doppler Spreading of the spectrum of the received signal due to the influence of the mobile receiver. Occurs.

In consideration of the transmission and reception in such a channel environment, the DMB transmission method uses differential coding based on Orthogonal Frequency Division Multiplexing (OFDM).

At this time, the DMB transmission signal is transmitted with a very small signal strength compared to the existing analog radio broadcasting signal, and considering the mobile reception as in a car in a severe fading channel environment such as downtown, the signal strength of the actual received signal is Very small Therefore, a broadcast receiver capable of receiving DMB should be able to receive a received signal as much as possible in such a poor reception environment and correct a transmission error. In addition, considering the fact that it is a mobile terminal, providing the maximum reception performance at a limited cost is a key requirement of a broadcast receiver configuration.

In such a DMB, at least one ensemble corresponding to one physical channel frequency range may be serviced.

1 illustrates an example of one ensemble structure, in which one ensemble is composed of at least one service, and each service is composed of at least one service component.

The service corresponds to one channel of TV or radio. The service component means video, audio, traffic information, or broadcast service information constituting a broadcast. The service component may come from each sub-channel of the main service channel (MSC) and the fast information data channel (FIDC).

The multiplexing configuration information (MCI) is used to indicate what services are multiplexed in the ensemble, what service components constitute each service, and where the service components are located. That is, the MCI includes information on how the MSC is configured in the same frame, and the SI includes information on what services are provided through the MSC.

The MCI is transmitted through a fast information channel (FIC) in a DMB transport frame.

That is, the DMB transmission frame is composed of a synchronization channel (Fynchronization Channel), a fast information channel (FIC), and a main service channel (MSC).

The synchronization channel has a predetermined shape so that the DMB receiver recognizes the beginning of the frame, and is assigned a null symbol and a phase reference symbol (PRS).

The FIC is used to transmit various types of information for receiving a broadcast service, and is composed of an MCI, a service information (SI), and a fast information data channel (FIDC).

The MSC is composed of one or more Common Interleaved Frames (CIFs), and is used for transmitting broadcast services such as video, audio, and data. The smallest unit that can allocate an address in one CIF is a capacity unit (CU), and a plurality of CUs are connected to form one subchannel. In order to transmit the service component of the MSC, two data transmission modes, a stream mode and a packet mode, are supported.

In other words, the control information FIC contains information indicating the structure of data carried in the CIF in the MSC, which is data information, and each CIF contains actual data such as video data and audio data. The biggest difference between the FIC and the MSC depends on whether it is time de-interleaving and transmitted. The FIC is not time interleaved, the MSC is time interleaved, and most of the data is transmitted through the MSC.

And the data service that can be provided by DMB is various. For example, Program Associated Data (PAD) and Independent Data (N-PAD; Non Program Associated Data), Service Information (SI), Multimedia Object Transfer (MOT) Slide Show, Broadcast Web Site; BWS), Interactive Services, and Live Video Services.

The transmission mode most commonly used in the data transmission is a packet mode, in which data is divided into data groups. In addition, the MOT protocol is a transmission protocol that delivers a multimedia object (that is, content) using a data channel to various types of receivers capable of receiving multimedia decodes, and its targets include text, images, video, and audio. At this time, in the terrestrial DMB, the MOT transmission makes the multimedia object into the MOT standard and then transmits it in packet mode or PAD.

In such a DMB, there is a need for conditional access (CA) for the purpose of charging for paid services or viewing age-restricted services.

Accordingly, an object of the present invention is to provide a broadcast receiver and a reception method for performing restoration to a state before reception restriction on mobile broadcast data that is reception-restricted and transmitted.

In order to achieve the above object, a broadcast receiver according to an embodiment of the present invention comprises an interface consisting of a physical layer and at least one protocol layer; A host that receives the mobile broadcast service and performs decryption and decoding; And at least one module detachable from the host, wherein the module is configured to include a card including information for decryption of the host and a memory including the card operating program. do.

The host may control the operation of the card by receiving a card operating program from the memory in the module when the insertion of the module is detected.

The reception method of the broadcast receiver according to the present invention comprises: setting a decryption execution environment by receiving a card operating program from a memory in the module when a module is inserted; Determining whether to restrict reception when a mobile broadcast service is received; If the mobile broadcast service is restricted in reception, communicating between the host and a card in a module through the interface to decrypt the received restricted mobile broadcast service; And decoding and outputting the decrypted mobile broadcast service.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention that can specifically realize the above object will be described. At this time, the configuration and operation of the present invention shown in the drawings and described by it will be described as at least one embodiment, by which the technical spirit of the present invention and its core configuration and operation is not limited.

In addition, the terminology used in the present invention is a general term that is currently widely used as much as possible, but in certain cases, the term is arbitrarily selected by the applicant. In this case, since the meaning is described in detail in the description of the present invention, It is intended that the present invention be understood as the meaning of the term rather than the name.

In general, a CA method may be used to modify a signal to be restricted received using an arbitrary key, or to mix a signal itself. It is used in various terms such as scramble, encryption, etc., and the term is unified in the present invention as an encryption. The encryption includes the meaning of scramble. The reverse process of the encryption is called decryption, which likewise includes the meaning of descramble.

In the DMB system, there may be several paths for performing CA in the DMB system, and in the present invention, three paths are used as examples for convenience of description, and each of the sub-channel CA mode, data group CA mode, and MOT CA mode. It is called.

The sub channel CA mode is a mode in which an encryption is performed at a sub channel stage, and all data included in the sub channel are encrypted. That is, the entirety of a specific subchannel such as an audio stream including a PAD, a packet mode channel, and a stream mode channel can be encrypted.

The data group CA mode is a mode for performing encryption at the data group end, and is applied to all DMB data transmission protocols such as IP tunneling, MOT, TDC, etc. using the MSC data group. That is, data not included in the data group is not encrypted, and in this case, both encrypted data and unencrypted data may exist in one subchannel. For example, an audio program may not be encrypted in one subchannel, but only data encrypted in the data group stage may be encrypted.

The MOT CA mode is a mode for performing encryption at the MOT stage, and is applied to files transmitted using the MOT directory mode.

2 is a block diagram showing an embodiment of a broadcast receiver capable of receiving mobile broadcast according to the present invention, and is largely comprised of a host 100 and a module 150.

The host 100 is a broadcast receiver main body capable of receiving a mobile broadcast, and includes a control unit (CPU) 101, a data input unit 102, a first memory 103, a second memory 104, and a smart card interface unit ( 105, the decoder 106, and the decoder 107.

The module 150 may be attached to or detached from the host 100. The module 150 includes a smart card 151 and an external memory 152.

The smart card 151 may include information for checking a reception qualification of a limited reception DMB service, information for user authentication, information for decryption, and the like. In this case, the smart card 151 may directly provide an encryption key value necessary for decryption, or may provide information for solving an encryption key value transmitted from a transmitter.

In order to use the information stored in the smart card 151, various programs are required. The programs are stored in the external memory 152. That is, the external memory 152 stores a smart card operation program for managing and operating information stored in the smart card 151.

The smart card operating program is a program that allows the host 100 to read data stored in the smart card 151 and perform a corresponding process.

If it is assumed that the encryption method of the DMB service is different for each smart card manufacturer, the smart card operating program stored in the external memory 152 may be different for each smart card manufacturer. Here, the encryption method may include a charging method, a subscriber management method, etc., as well as a method of actually encrypting data.

On the other hand, the controller 100 in the host operates the program stored in the first memory 103 to control the overall operation of the broadcast receiver, and the smart card 151 in the module 150 through the smart card interface (I / F) Send and receive the necessary data.

The data input unit 102 in the host receives a DMB service of a specific channel transmitted from a transmitter, performs demodulation, and stores the demodulated data in a first memory (MEM1 RAM) 103 through an internal bus.

The second memory 104 in the host stores an operating system (OS) and applications for operating the host 100. The programs are booted at the same time power is supplied to the host 100. Is copied to the corresponding area of the first memory 103. This causes the host 100 to operate.

Meanwhile, if the DMB service stored in the first memory 103 is encrypted, the encrypted DMB service is decrypted through the decoder 106 and then output to the decoder 107. If not encrypted, the decoder 106 is bypassed and output to the decoder 107 or directly to the decoder 107.

In order to decrypt the DMB service encrypted by the decryptor 106, the key used for the encryption must be known.

In this case, the key information may be transmitted by being encrypted by the transmitter or may be input from the smart card 151. However, in order to receive the encrypted key information, the control unit 101 requires a corresponding process. In other words, the user's initial authentication, authentication of the DMB service, key value management, etc. are required, and a program for performing such processing will be referred to as a smart card operation program in the present invention. In this case, the smart card operation program may be different for each broadcasting station (eg, CAS solution company and smart card manufacturer), and may also be different for each OS installed in the host 100.

The smart card operating program is stored in the external memory 152 in the module 150.

Therefore, when the insertion of the module 150 is detected, a program stored in the external memory 152 in the module 150, for example, a smart card operating program is stored in the corresponding memory of the first memory 103 through the second memory 104. Copied to the area.

That is, when the module 150 is inserted into the host 100, a program stored in the external memory 152 of the module 150 and an application included in the host 100 are operated together. In other words, the host 100 sets an environment in which the decryption can be performed by executing the smart card operating program transmitted from the external memory 152 in the module.

2 illustrates a method of receiving a DMB service according to an embodiment of the present invention. When a module insertion is detected (step 201), a program including a smart card operating program stored in an external memory 152 in the module 150 is shown. Are downloaded to the first memory 103 through the second memory 104 of the host 100 (step 202).

At this time, if the received DMB service is encrypted (step 203), the smart card operating program stored in the first memory 103 is driven, and information necessary for decryption is received from the smart card 151 in the module 150. The received and decrypted encrypted DMB service is performed (step 204). The decrypted DMB service in step 204 is normally provided to the user through the output unit 108 after being decoded by the decoder 107 (step 205).

Wherein step 204 includes user authentication, DMB service authentication, decryption of the encrypted key, and the like. At this time, if the user is not a legitimate user or DMB service authentication is not performed, the encrypted DMB service is not decrypted. In this case, the user cannot normally use the DMB service. For example, if the pay DMB service selected by the user is transmitted from the first broadcast station and the module 150 is a module provided from the second broadcast station, the pay DMB service is not decrypted. Also, if the same broadcaster is not a legitimate user, the paid DMB service is not decrypted.

In the present invention, the interface for performing communication between the module 150 and the host 100 may be, for example, a standard satisfying ISO / IEC 7816 and may be applied through a protocol such as an application protocol data unit (APDU). It handles the data exchange and / or transaction between the host 100 and the module 150. In this case, the interface may additionally include an interface for communicating with the host bus of the controller 101.

An interface for communication between the host 100, the smart card 151 and the external memory 152 in the module 150 is called a common interface (CI). The CI consists of a physical layer (ie, smart card interface) and one or more protocol layers. The protocol layer that communicates between the host and the module has a structure including one or more layers that provide independent functions in consideration of scalability later.

The protocol layer may be defined as follows.

(1) int CAM_open (void * path, int flag);

It serves to obtain a file descriptor for the smart card 151 included in the module 150.

(2) int CAM_close (int fd);

It serves to stop access to the smart card 151 included in the module 150.

(3) Int CAM_ioctl (int fd, int request, / * void * arg * /);

Defining an interface with the smart card 151, the arguments and actions that the function receives depending on the request value may vary. Actions you can take with this function can include:

(a) Checking the presence or absence of smart card 151

(b) Changing the Power of the Smart Card 151

This is necessary in the interface for changing the contents of the smart card 151.

(c) Reset of smart card 151

(d) setting and obtaining UART parameters of the smart card 151 (set / get)

(e) Performs communication with the smart card 151, and is defined as a function interface used for receiving and sending substantial data.

The above definition shows one embodiment, and the required interface can be added using CAM_ioctl.

Meanwhile, the present invention may integrate the smart card 151 and the external memory 152 into the module 150 to allow the host 100 to be attached or detached through one slot, or the smart card 151 and the external device. Memory 152 may also be detached to allow removal through each slot. In the latter case, the external memory 152 may be connected to an external interface of the host 100, for example, USB, IRDA, or memory card. This method is used when a plurality of broadcasting stations use different services using the same platform, and can be used in a situation where a user can select a plurality of broadcasting stations.

3 illustrates an example, in which an external memory 180 is connected through a USB interface 170. In this case, the smart card 160 may store the same information as the smart card 151 of FIG. 1 or may store other information.

When the external memory 180 is inserted, the second memory 104 reads the smart card operating program from the external memory 180 through the USB interface 170 and stores the smart card operating program in the first memory 103.

Since the operation after the smart card operating program is copied to the first memory 103 is the same as in FIG. 1, detailed description is omitted.

3, since the smart card 160 and the external memory 180 operate independently, the authentication process is performed not only when the insertion of the smart card 160 is recognized but also when the insertion of the external memory 180 is recognized. need. This is because a user may insert a smart card and an external memory provided by different broadcasting stations.

Meanwhile, the present invention may apply the module 150 of FIG. 1 to the structure of FIG. 3 as it is. In other words, the external memory can be inserted through the USB interface at the same time as the module equipped with the external memory. In this case, the external memory connected to the USB interface may be used for patching the smart card operating program or for updating information stored in the smart card.

The present invention is not limited to the above-described embodiments, and as can be seen in the appended claims, modifications can be made by those skilled in the art to which the invention pertains, and such modifications are within the scope of the present invention.

According to the broadcast receiver and the method for receiving a mobile broadcast according to the present invention described above, the smart card and the smart card operating program without a decryption function is stored in a module detachable to a host capable of receiving the mobile broadcast. By providing only the external memory, it is possible to solve the disadvantage that the module is larger and to shorten the development time of the host. That is, the development time of the broadcast receiver can be shortened because a smart card operating program that can be different for each broadcast station and host does not need to be developed by a host manufacturer, that is, a broadcast receiver manufacturer.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (12)

An interface consisting of a physical layer and at least one protocol layer; A host that receives the mobile broadcast service and performs decryption and decoding; And It is configured to include at least one module detachable to the host, And the module comprises a card including information for decryption of the host and a memory including the card operating program. The method of claim 1, wherein the host is And receiving a card operating program from the memory in the module when the insertion of the module is detected to control the operation of the card. The method of claim 2, wherein the host And setting an environment in which a decryption can be performed by executing a card operating program transmitted from the memory in the module. 4. The method of claim 3, wherein the host is And if the decryption environment is set and the received mobile broadcast service is restricted in reception, communicating with a card in the module to decrypt the received restricted mobile broadcast service through the interface. The method of claim 1, And the card in the module includes information for checking the reception qualification of the restricted mobile broadcast service. The method of claim 1, And the card in the module includes key information for decryption of the host. The method of claim 1, wherein at least one protocol layer of the interface is And a protocol for controlling a file descriptor request for the card, an access stop request for the card, and a card operation according to the request value. The method of claim 7, wherein The card operation control may include at least one of checking whether a card exists, changing a power supply of a card, resetting a card, setting a card parameter, and communicating data with a card. In the receiving method of a broadcast receiver having a structure as claimed in claim 1, Setting a decryption execution environment by receiving a card operating program from a memory in the module when the module is inserted; Determining whether to restrict reception when a mobile broadcast service is received; Decrypting the received restricted mobile broadcast service by receiving information for decryption from the card by communicating with the card through the interface if the mobile broadcast service is restricted in reception; And And decoding and outputting the decrypted mobile broadcast service. The method of claim 9, Requesting a file descriptor for the card; Requesting to stop access to the card; Receiving method comprising the step of performing the interface between the host and the module, including at least one of the card operation control step according to the request value. The method of claim 10, The card operation control step may include at least one of checking whether a card exists, changing a power supply of a card, resetting a card, setting a card parameter, and communicating data with a card. 10. The method of claim 9, wherein the decryption step is And receiving a confirmation of a reception eligibility of an encrypted mobile broadcast service through an interface with the card.

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