JP2000332708A - Digital broadcast receiver and digital broadcast transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital broadcast receiver that reduces the power consumption in a broadcast program non-viewing state (standby state) or facilitates realization of the reduction in the power consumption on the condition that there is a case that information requiring a processing dealing with an entitlement management message(EMM) is broadcast at all times. SOLUTION: This digital broadcast receiver 110 is provided with a front end section 111 or the like that receives digital broadcast data that are broadcast, an EMM detection section 112 that detects an EMM included in the received data, a microcomputer 118 that executes a control processing dealing with the EMM so long as the microcomputer 118 receives supply of a clock signal, and a clock control section 117 that starts supplying the clock signal to the microcomputer 118, when the EMM detection section 112 detects the EMM and stops supply of the clock signal to the microcomputer 118 after the microcomputer 118 completes the execution of the control processing dealing with the EMM.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital broadcast receiving apparatus and a digital broadcast receiving apparatus, and more particularly to a technique for reducing the power consumption of a digital broadcast receiving apparatus for receiving a digital broadcast.

[0002]

2. Description of the Related Art In recent years, satellite digital broadcasting has started,
A large number of programs are provided using multiple channels, and a technology that allows only those who have a viewing contract (hereinafter, referred to as “subscribers”) to view programs has been used. . 2. Description of the Related Art In a conventional digital broadcast transmitting / receiving system, particularly a digital broadcasting transmitting / receiving system that allows only a subscriber to view a program, as described in Japanese Patent Publication (JP-B-7-93621), The broadcast transmitting apparatus transmits, to a transport stream (TS) called an EMM (entitlement management message), an encryption key for enabling viewing of program data to be sent after being scrambled, information for decryption control, and the like. When the digital broadcast receiving apparatus receives the EMM and satisfies a predetermined condition using the received information for decryption control, an encryption key, or the like, it descrambles or decrypts the program data. The method used is generally used.

[0003] Here, the TS is a transmission unit of data transmitted by the digital broadcast transmitting apparatus, and is a sequence of TS packets composed of, for example, 188 bytes.
(Strength Experts Group 2) standard. Specifically, it is described in the ISO / IEC standard 13818-1 (MPEG2 system) standard.

The EMM is basically a code used for controlling a decoder on the digital broadcast receiving apparatus side, and is composed of an encryption key, information for decryption control, and the like. Is transmitted intermittently about three times. In addition, in the EMM, information indicating a viewing result recorded on the digital broadcast receiving apparatus side in order to realize billing control according to viewing of a pay program is included in the EMM. Various controls and various services for the digital broadcast receiver such as those containing instruction information for realizing the function of transmitting to the broadcast center through the public line network via a modem etc. connected to the digital broadcast receiver are provided. Some are broadcast for purposes.

[0005] An outline of a conventional digital broadcast transmitting / receiving system that allows only subscribers to view digital broadcasts will be described below. FIG. 9 is a schematic configuration diagram of a conventional digital broadcast transmission / reception system. The conventional digital broadcast transmitting / receiving system shown in FIG.
And a digital broadcast receiving apparatus 510. Although only one is shown in the figure, there are usually a plurality of digital broadcast receiving apparatuses for receiving a program or the like transmitted from the digital broadcast transmitting apparatus 500.

The digital broadcast transmitting apparatus 500 is an apparatus for broadcasting digital broadcast program data and related data, and includes a broadcast management section 501, a program transmitting section 502,
An EPG transmission unit 503, a conditional access information transmission unit 504, a subscriber information management unit 505, and an encoder unit 506 are provided.
The broadcast management unit 501 is a unit that performs overall control such as specifying broadcast content, and the encoder unit 506 is a unit that has a function of multiplexing various data into a TS and broadcasting the data.

[0007] The program transmitting section 502 is a section having a function of transmitting moving picture data and audio data as the contents of a broadcast program to the encoder section 506.
This is a part having a function of transmitting data necessary for an electronic program guide (EPG) to the encoder unit 506, and the conditional access information transmitting unit 504 is a part having a function of determining the contents of the EMM and transmitting the EMM to the encoder unit 506. is there.

[0008] The subscriber information management unit 505 is a part that receives information indicating the viewing results transmitted from the digital broadcast receiving device 510 or the like via the public line network 520, and performs processing such as charging for each subscriber. Also, the digital broadcast receiving apparatus 510 includes the digital broadcast transmitting apparatus 500.
This is a device for receiving a digital broadcast transmitted from a CDMA system, and includes a front end unit 511, a TS decode / descramble unit 512, an EMM detection unit 513, an AV decode unit 514, a peripheral I / O unit 515, and a microcomputer 516.

[0009] The front end unit 511 receives a digital broadcast via an antenna, receives a required TS, and receives a T
This is a part to be transmitted to the S decode / descrambling unit 512. The TS decode / descramble unit 512 cuts out a TS packet from the transmitted TS, and
Extracts video data, audio data, and other data such as EMM according to the filter condition set by
Since the packet is scrambled, descrambling is performed using an encryption key notified from the microcomputer.
Note that the TS decode / descramble unit 512 has a plurality of channels, and can extract a plurality of data in parallel.

The EMM detector 513 corresponds to a part of the channel of the TS decode / descrambler 512,
This part has a function of detecting and extracting MM. The AV decoding unit 514 includes a TS decoding / descrambling unit 5
When receiving the moving image data and audio data output from the microcomputer 12, the microcomputer 516 decompresses the moving image data and audio data under the control of the microcomputer 516 and outputs the video signal and the audio signal to an external monitor or the like. .

The peripheral I / O unit 515 is an interface unit with an external device such as a modem. Also, the microcomputer 51
Reference numeral 6 denotes a microcontroller (microcomputer) formed of one semiconductor chip having the function of a computer, which is a part that performs overall control of the digital broadcast receiving apparatus 510, and includes a TS decode / descrambling unit 512.
, And controls the AV decoding unit 514. When an EMM is detected by the EMM detection unit 513, various control processes are performed according to the contents of the EMM. For example, if the content of the EMM is an encryption key,
A process for giving this to the TS decode / descramble unit 512 and a process for controlling the modem so as to send information indicating the viewing result to the digital broadcast transmitting apparatus through the public line network 520 are performed. Note that the digital broadcast transmitting device 500
The encryption key for descrambling the moving image data and the audio data is changed as needed, and the information serving as the basis for deriving a new encryption key is broadcast as the content of the EMM as needed.

As described above, the EMM transmitted by the digital broadcast transmitting apparatus 500 includes information for performing billing control as described above. Therefore, the digital broadcast receiving apparatus 510 is operated by a user who is a subscriber. Even when the program receiving function is stopped in response to the EMM (hereinafter, referred to as a “standby state”), when the EMM is sent, it is necessary to receive the EMM and perform a process corresponding to the content. .

Here, the standby state is a state in which the power of the apparatus main body is turned on but the program itself is not received and no video or audio signal is output, that is, a screen of a monitor or the like receiving the output. Means a state in which nothing is displayed, and a state in which a video or audio signal is output, as opposed to the standby state, is a viewing state. For example, a button is provided on the front panel or the like of the digital broadcast receiving apparatus 510, and each time the user presses the button, the viewing state and the standby state are alternately switched.

[0014]

However, since information such as EMM is transmitted from the digital broadcast transmitting apparatus side to realize various controls or services regardless of whether or not the user is watching the digital broadcast, the conventional digital broadcast reception is not performed. The apparatus always supplies power and a clock signal to the microcomputer 516 in the viewing state and the standby state so that the information can be processed.

By the way, in recent years, with increasing awareness of the necessity of protecting the global environment, it has been desired to reduce the power consumption of electric equipment. Therefore, the present invention is based on the premise that information such as the above-mentioned EMM, which needs to perform corresponding processing even in the standby state, may be broadcast from the digital broadcast transmitting apparatus, and the power consumption in the standby state under this precondition is It is an object of the present invention to provide a digital broadcast receiving apparatus which reduces the power consumption and facilitates realization of power consumption reduction, and a digital broadcast transmitting apparatus corresponding to the digital broadcast receiving apparatus.

[0016]

In order to achieve the above object, a digital broadcast receiving apparatus according to the present invention is a digital broadcast receiving apparatus for receiving data which is broadcast by multiplexing program data and control messages constituting a broadcast program. A receiving device for receiving broadcast data; a control message detecting device for detecting that the control message is included in the data received by the receiving device; A control message processing unit that takes one of a second state having a processing capacity higher than the first state and executes a control process corresponding to the control message in the second state; State control means for setting the control message processing means to the second state when a message is detected.

Thus, until a control message such as an EMM is received, the supply of the clock signal to the control message processing means for processing the control message is stopped, the supply clock frequency is reduced, or the supply of power is stopped. Even when the operation of the control message processing means is suppressed, when the control message is received, the clock signal supply to the control message processing means is started, the supply clock frequency is increased, or the power supply is started. Since the suppression of the operation is canceled and the control process corresponding to the control message is executed, the power consumption can be reduced easily by adding a simple means for suppressing the operation of the control message processing unit until the control message is received. It can be realized.

A digital broadcast transmitting apparatus according to the present invention is a digital broadcast transmitting apparatus for transmitting data including a control message by a digital broadcast system, wherein each of the plurality of control messages is transmitted to a plurality of digital broadcast receiving apparatuses. Control message classifying means for classifying the digital broadcast receiving apparatuses into groups to which control processing corresponding to the control message belongs when the digital broadcast receiving apparatuses are classified into a plurality of groups; Control message transmitting means for transmitting the generated control messages at different times, and time information indicating the time at which the control message transmitting means transmits the control messages of each group, prior to the transmission of the control message. Information transmission means. The features.

Thus, the digital broadcast receiving apparatus which receives the digital broadcast transmitted by the digital broadcast transmitting apparatus, and which belongs to each group, specifies the time at which the control message to be handled by the apparatus is broadcast from the time information. The circuit for detecting a control message or the like can be stopped until that time, so that power consumption can be suppressed.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. << Embodiment 1 >> A digital broadcast transmitting / receiving system according to Embodiment 1 of the present invention will be described.

<Configuration> FIG. 1 is a configuration diagram of a digital broadcast transmitting / receiving system according to the first embodiment. The digital broadcast transmitting / receiving system shown in FIG. 1 includes a digital broadcast transmitting device 100 and a digital broadcast receiving device 110. Although only one is shown in the figure, there are a plurality of digital broadcast receiving apparatuses for receiving a program or the like transmitted from the digital broadcast transmitting apparatus 100.

The digital broadcast transmitting apparatus 100 is a device for broadcasting digital broadcast program data and related data, similar to a conventional digital broadcast transmitting apparatus. EPG
It includes a transmitting unit 103, a conditional access information transmitting unit 104, a subscriber information managing unit 105, and an encoder unit 106.
The broadcast management unit 101 is a part that performs overall control of the digital broadcast transmission device 100, and manages, for example, program scheduling, determination of broadcast contents, determination of a broadcast schedule, and the like.

The program transmitting unit 102 has a function of transmitting moving image data and audio data, which are the contents of a broadcast program, to the encoder unit 106. The EPG transmitting unit 103
This part has a function of transmitting data necessary for an electronic program guide (EPG) to the encoder unit 106. The conditional access information transmission unit 104 receives the instruction from the broadcast management unit 101,
A part having a function of determining the content of the EMM and transmitting the EMM to the encoder unit 106 by referring to the information of the subscriber managed by the subscriber information management unit 105;
EMM transmission control is performed. Limited reception information transmission unit 104
For example, in addition to transmitting the information that is the basis of the encryption key for decrypting the scramble applied to the video data and audio data that make up the program at any time, if necessary, an e-mail addressed to an individual In the form of EMM, and in order to realize charging control according to the viewing of the pay program, a modem connected to the digital broadcast receiving apparatus transmits information indicating the viewing result recorded on the digital broadcast receiving apparatus side. The instruction information for realizing the function of transmitting to the broadcasting center through the public line network via the public network is transmitted every certain period.
Communicate as MM contents.

The subscriber information management unit 105 manages information about the subscriber, receives information indicating the viewing result transmitted from the digital broadcast receiving apparatus 110 or the like via the public line network 130, and performs charging and the like for each subscriber. This is the part that performs processing. The encoder unit 106 includes the program transmission unit 10
2. EPG transmitter 103 and conditional access information transmitter 104
This is a part having a function of multiplexing various data transmitted from the PC into a TS, performing digital modulation, and broadcasting. In addition,
For video data and audio data, the encoder unit 1
06 performs MPEG compression and scrambling before multiplexing.

The digital broadcast receiving apparatus 110
This is a device for receiving a digital broadcast transmitted from the digital broadcast transmitting device 100.
1, the TS decode / descramble section 120, and the EM
M detection unit 112, DMA control unit 113, AV decoding unit 114, memory 115, peripheral I / O unit 116
, A clock control unit 117, and a microcomputer 118, which are connected to the public network 130,
It is a device to which 40 can be attached.

Here, the front end unit 111 receives the digital broadcast via the antenna, performs demodulation, error correction, and the like, and converts the TS into the TS decode / descramble unit 1.
20. The TS decode / descramble unit 120 cuts out a TS packet from the transmitted TS, and extracts video data, audio data, and other data such as EMM according to the filter condition set by the microcomputer 118. Since TS packets for moving image data and audio data are scrambled, descrambling is performed using an encryption key notified from the microcomputer. The TS decode / descramble unit 120 has 52 channels, and can extract a plurality of data in parallel.

The EMM detection unit 112 corresponds to the four channels of the TS decode / descramble unit 120,
Is a part having a function of detecting and extracting Note that TS
Decode / descramble section 120 and EMM detection section 1
Details of 12 will be described later. DMA control unit 113
Transfers the data extracted by the TS decode / descramble section 120 including the EMM detection section 112 to the memory 115 without the intervention of the microcomputer 118. Accordingly, for example, when the EMM is detected by the EMM detection unit 112, the EMM is transferred to the memory 115.

The AV decoding unit 114 includes a microcomputer 118
Receiving the video data and audio data output from the TS decode / descramble unit 120 stored in the memory 115, expands the video data and audio data, and controls the video signal and the audio signal to an external monitor. And the like. Memory 11
Reference numeral 5 denotes a memory for storing various programs to be executed by the microcomputer 118, and for storing moving image data, audio data, and other data such as EMM extracted by the TS decode / descramble unit 120. is there.

The peripheral I / O section 116 is an interface section with external devices such as a modem, a remote controller, an IC card 140 and the like. The IC card 140 includes a flash memory, and IDs and other information are recorded in the flash memory, and the user can view digital broadcasts by attaching the IC card to the digital broadcast receiving device 110. It should be noted that the information indicating the viewing result described above is stored in the IC card
Will be recorded.

The clock control unit 117 is connected to the peripheral I / O unit 1
Interrupt from 16, key input interrupt from front panel,
In response to the instruction from the microcomputer 118 and the notification of the EMM detection from the EMM detection unit 112, the notification to the microcomputer 118 and the control of the supply of the clock to the AV decoding unit 114 and the microcomputer 118, that is, the supply or the supply of the clock This is a part for controlling whether to stop. Note that the clock control unit 117 also holds state information indicating whether the apparatus is currently in the standby state or the viewing state. here,
The clock refers to a so-called clock signal, that is, a synchronization signal.

The microcomputer 118 executes various programs stored in the memory 115 to
A part that performs overall control of the digital broadcast receiving apparatus 110. The PID is transmitted to the TS decode / descramble section 120 to separate and extract moving image data, audio data, EMM, and the like from multiplexed and broadcast data. A function of setting filter conditions such as the above, a function of controlling the AV decoding unit 114, a function of storing viewing results in the IC card 140,
A function of controlling each unit in the digital broadcast receiving apparatus 110 in response to a user operation performed through a front panel or a remote control of the digital broadcast receiving apparatus 110,
E when the EMM is detected by the EMM detection unit 112
It has a function of performing various control processes according to the contents of the MM.

Here, the various control processes performed by the microcomputer 118 according to the contents of the EMM include, for example, when the contents of the EMM are information serving as a basis of an encryption key, the information is recorded on the IC key and the information. This is a process of generating an encryption key based on the ID and giving it to the TS decode / descrambling unit 120. If the content of the EMM is a mail addressed to an individual, this is a process of storing it in the memory 115. If the content is instruction information for transmitting the information indicating the viewing result to the broadcasting center, modem control processing or the like is performed via the peripheral I / O unit 116 to thereby obtain the IC card 140.
Information indicating viewing results stored in the public network 13
This is a process of sending to the broadcast center through “0”.

FIG. 2 is a configuration diagram of the TS decode / descramble unit 120 including the EMM detection unit 112. As shown in FIG.
Is the channel data processing unit 121, the PID filter 12
2. It is composed of a descrambler 123, a formatter 124 and a section filter 125, has 52 channels, and can separate and extract up to 52 types of data from the input TS in parallel. The channel is used for the separation and extraction of EMM.
The channel is functionally represented as an EMM detector 112.

Here, the channel data processing section 121
It recognizes the packet boundary of the input TS and cuts out the TS packet. The PID filter 122 extracts a TS having a PID set as a filter condition by the microcomputer 118. The microcomputer 11
Reference numeral 8 designates a TS, which is a predetermined control table, by setting a predetermined PID in the TS decode / descramble section 120, and refers to the control table for moving image data, audio data, and EMM. PI
D can be obtained, and the obtained PID is further added to TS
An arbitrary TS is extracted by setting in the decode / descramble section 120.

The descrambler 123 uses the encrypted T
It descrambles S packets, and performs processing on TS packets of moving image data and audio data. The formatter 124 extracts data other than additional information such as a header from the TS packet.
The section filter 125 extracts a section having a section ID set as a filter condition by the microcomputer 118 from the sections extracted by the formatter.

<Data Structure> The data structure of the TS packet processed by the above-described EMM detector 112 will be described below. FIG. 3 is a diagram showing a data structure of a TS packet. FIG. 1 shows an example of a TS packet having an EMM. In this TS packet, a set of a section header and section data follows the additional information such as a header. This section data indicates the contents of the EMM.

The section ID of the EMM is determined in advance, and the EMM detecting section 112 uses the section filter 125 based on the section ID of the EMM.
Is detected and extracted. <Operation> The operation of the digital broadcast receiving apparatus 110 having the above-described configuration will be described below.

First, the digital broadcast receiving apparatus 110
It is executed in response to a viewing stop instruction from the user, that is, when the state of the own device is changed from the viewing state to the standby state in response to a user operation performed via the front panel or the remote controller and having the meaning of the viewing stop instruction. The processing (hereinafter, referred to as “standby state transition processing”) will be described.

FIG. 4 is a flowchart showing the standby state transition processing. When the microcomputer 118 receives a notification from the clock control unit 117 that a key input on the front panel or a remote control operation has been performed, and determines that the request requires the standby state transition processing, the microcomputer 118 performs the standby procedure according to the procedure shown in FIG. Execute state transition processing.

First, the microcomputer 118 performs TS decoding
The processing of each channel of the descrambling unit 120 is stopped, and the TS decoding / descrambling unit 120 is operated so that only the four channels required as the EMM detecting unit 112 operate.
(Step S11). As a result, the TS decode / descramble section 120 operates only four of the 52 channels.
Therefore, since only the EMM detection unit 112 operates, even in the standby state, only the EMM is detected and extracted from the broadcast data.

Subsequently, the microcomputer 118 controls the AV decoding unit 11 to stop the AV decoding unit 114.
4 and set the clock control unit 11 so that the clock supply to the AV decoding unit 114 is stopped.
7, the clock control unit 117 stops supplying the clock to the AV decoding unit 114 (step S12). The AV decoding unit 114 to which the clock is no longer supplied stops operating.

After stopping the supply of the clock to the AV decoding unit 114, the microcomputer 118 sets the CPU cache in the microcomputer not to be used, that is, to an off state (step S13), and stops the clock supply to itself. Then, the clock control unit 117 issues an instruction to the clock control unit 117, and in response to this, the clock control unit 117 stops the clock supply to the microcomputer 118 (step S14). As a result, the microcomputer 118 to which the clock is no longer supplied stops operating until the clock supply is started again. In the standby state, the microcomputer 118 does not need to control the AV decoding unit 114 or the like, and the required amount of operation is lower than in the viewing state, so the CPU cache is turned off.

When shifting to the standby state, the clock control section 117 changes the held state information to a value indicating that the state is the standby state. When the microcomputer 118 changes the setting of the CPU cache, the clock control unit 117 receives information indicating the changed state from the microcomputer 118, and only when the CPU cache is set to the ON state, The clock is supplied to the CPU cache, and the clock is not supplied to the CPU cache when the clock is set to the off state.

Next, the digital broadcast receiving apparatus 110 when the EMM is sent in the standby state
Will be described. FIG. 5 shows the EMM detector 112.
Detects an EMM, the digital broadcast receiver 11
10 is a flowchart showing an EMM process performed by the EMM. EM
When detecting the EMM, the M detection unit 112 notifies the clock control unit 117 of the detection. When the clock control unit 117 receives the notification in the standby state, the microcomputer 118
The clock supply to is started (step S21).

The microcomputer 118 to which the clock is supplied,
The EMM detecting unit 112 receives a notification that the EMM has been detected from the clock control unit 117, and
3 and performs various control processes in accordance with the contents of the EMM stored in the memory 115, such as controlling a modem to transmit viewing information to a broadcast center via a public network (step S3). S22).

When the microcomputer 118 completes various control processes according to the EMM, if the state information held by the clock control unit 117 indicates a standby state, the clock control unit 117 stops the clock supply to itself. , And in response to this, the clock control unit 117 stops the clock supply to the microcomputer 118 (step S2).
3). As a result, the microcomputer 118 to which the clock is no longer supplied stops operating until the clock supply is started again.

If the EMM detection unit 112 detects an EMM in the viewing state instead of the standby state, the process proceeds to step S23 of steps S21 to S23.
Only 22 is executed. Next, the digital broadcast receiving apparatus 110 responds to a user's viewing start instruction,
Processing to be performed when the state of the apparatus itself is changed from the standby state to the viewing state in response to a user operation performed through the front panel or the remote controller and having the meaning of the viewing start instruction (hereinafter, referred to as “viewing state transition processing”) ) Will be described.

FIG. 6 is a flowchart showing the viewing state transition processing. When the clock control unit 117 receives the notification that the front panel key input or the remote control operation has been performed, and determines that the request requests the viewing state transition processing, the clock control unit 117 executes the viewing state transition processing according to the procedure shown in FIG. Execute. First, the clock control unit 117 starts clock supply to the microcomputer 118, notifies the microcomputer of the transition to the viewing state (step S31), and starts clock supply to the AV decoding unit 114 (step S32).

The microcomputer 118, having received the notification of the transition to the viewing state, executes a predetermined control program so that the AV decoding unit 114 can operate.
A value is set in the register of the decoding unit 114 (step S32). Thus, the AV decoding unit 114 can expand the moving image data and the audio data. Subsequently, the microcomputer 118 sets a value in a register of the TS decode / descramble unit 120 so that all the channels of the TS decode / descramble unit 120 can be operated (step S34), and uses the CPU cache in the microcomputer. To be turned on, that is, set to an on state (step S3).
5).

After shifting to the viewing state, the microcomputer 118 receives a user operation performed through a front panel or a remote controller, and receives a program requested by the user in response to the operation, and outputs the program to a monitor or the like. It controls the end unit 111 and the AV decoding unit 114 and sets filter conditions for the TS decoding and descrambling unit 120.

When the clock control unit 117 shifts to the viewing state, the clock control unit 117 changes the held state information to a value indicating the viewing state. As described above, the digital broadcast receiving apparatus 110 operates in the standby state,
The number of channels used by the S-decode descrambling unit 120 is reduced, the CPU cache is turned off, the clock supply to the AV decoding unit 114 is stopped, and the EMM is received and the corresponding process is executed. Since the clock supply to the microcomputer 118 is also stopped except during the period, the power consumption in the standby state is lower than when all of them are operating. << Embodiment 2 >> A digital broadcast transmitting / receiving system according to Embodiment 2 of the present invention will be described.

<Configuration> FIG. 7 is a configuration diagram of a digital broadcast transmission / reception system according to the second embodiment. In the figure, the same components as those described in the first embodiment are denoted by the same reference numerals. The digital broadcast transmitting / receiving system shown in FIG.
0 and the digital broadcast receiving apparatus 210.

Although only one is shown in FIG.
There are a plurality of digital broadcast receiving apparatuses that receive programs and the like transmitted from the digital broadcast transmitting apparatus 200. Further, the plurality of digital broadcast receiving apparatuses are conceptually divided into a plurality of groups based on the ID recorded on the attached IC card 140, and each digital broadcast receiving apparatus belongs to any one group. This grouping is a concept used in the destination management unit 207 and the like, which will be described later. Here, the ID is a number, and there are two groups, A group and B group.
The group includes a digital broadcast receiving apparatus on which an IC card having an even ID is attached, and the B group includes the I card.
It is assumed that a digital broadcast receiving apparatus to which an IC card with an odd number D is mounted belongs.

Digital broadcast transmitting apparatus 200 includes broadcast managing section 101, program transmitting section 102, and EPG transmitting section 10
3, a conditional access information transmission unit 204 having a destination management unit 207, a subscriber information management unit 105, and an encoder unit 1
06. This digital broadcast transmitting apparatus 200
Is the digital broadcast transmitting apparatus 10 shown in the first embodiment.
It is basically the same as 0, and differs only in having a destination management unit 207.

The transmission destination management unit 207 discriminates the EMM according to the content, and transmits an EMM dedicated to the A group such as a mail addressed to an individual to a digital broadcast receiving apparatus belonging to the A group.
And an EMM dedicated to the B group, such as an e-mail addressed to an individual to the digital broadcast receiving apparatus belonging to the B group, is controlled to be broadcast in different time zones. It should be noted that the content includes information that must be transmitted to any digital broadcast receiving apparatus, such as information serving as the basis of an encryption key.
The MM is controlled so as to be broadcast in a different time zone from the EMM dedicated to both groups. That is, the EMMs to be transmitted are classified into groups to which the digital broadcast receiving apparatuses to be processed corresponding to the EMMs belong,
The encoder unit 506 is controlled so that the classified EMMs are broadcast in different time zones.

Further, the transmission destination management unit 207 transmits the time at which the digital broadcast receiving device belonging to the group A transmits the EMM which needs to correspond, and the transmission destination management unit 207 transmits the EMM which the digital broadcast receiving device belonging to the group B needs to correspond to. E so that all EMMs include time information indicating
Generate MM. That is, the transmission destination management unit 207 determines that each of the plurality of grouped destinations
Is generated, and this is included in the contents of each EMM. Note that the time information included in the EMM by the transmission destination management unit 207 is information indicating the transmission time of the EMM to which each group to be transmitted next to the EMM should correspond.

Further, the digital broadcast receiving apparatus 210
This is a device for receiving a digital broadcast transmitted from the digital broadcast transmitting device 200, and includes a front end unit 11
1, the TS decode / descramble section 120, and the EM
M detection unit 112, DMA control unit 113, AV decoding unit 114, memory 115, peripheral I / O unit 116
A clock control unit 217 having a timer unit 219;
The device includes a microcomputer 218, is connected to the public network 130, and can mount an IC card 140. The digital broadcast receiving apparatus 210 is basically the same as the digital broadcast receiving apparatus 110 described in the first embodiment, but differs in that a clock control section 217 having a timer section 219 and a microcomputer 218 are provided.

Here, the front end section 111 is a section that receives digital broadcasting via an antenna, receives a necessary TS, and transmits it to the TS decode / descramble section 120. TS decode / descramble section 120
Operates by receiving a clock, cuts out a TS packet from the transmitted TS,
8 extracts moving image data, audio data, and other data such as EMM according to the filter condition set by T.8.
Since the S packet has been scrambled, descrambling is performed using the encryption key notified from the microcomputer. Note that the TS decode / descramble unit 120
It has two channels and can extract a plurality of data in parallel.

The EMM detecting section 112 corresponds to the four channels of the TS decode / descramble section 120,
Is a part having a function of detecting and extracting The DMA control unit 113 includes a TS decoding unit including the EMM detection unit 112.
The data extracted by the descrambler 120 is transferred to the microcomputer 2
18 to the memory 115 without intervention. Accordingly, for example, when the EMM is detected by the EMM detection unit 112, the EMM is transferred to the memory 115.

The AV decoder 114 is provided with a microcomputer 218
Receiving the video data and audio data output from the TS decode / descramble unit 120 stored in the memory 115, expands the video data and audio data, and controls the video signal and the audio signal to an external monitor. And the like. Memory 11
Reference numeral 5 denotes a memory for storing various programs to be executed by the microcomputer 218, and for storing moving image data, audio data, and other data such as EMM extracted by the TS decode / descramble unit 120. is there.

The peripheral I / O section 116 is an interface section with an external device such as a modem, an IC card 140 and the like. It should be noted that ID and other information are recorded on the IC card 140, and the user can view digital broadcasts by attaching the ID card to the digital broadcast receiving device 210. The clock control unit 217 controls the peripheral I / O
An interrupt from the O section 116, a key input interrupt from the front panel, an instruction from the microcomputer 218, and an EMM detection section 1
The microcomputer 218 receives the notification of the EMM detection from the
Notification, the TS decoding / descrambling unit 120,
This part controls the supply of the clock to the AV decoding unit 114 and the microcomputer 218, that is, controls whether to supply or stop the clock. The clock control unit 21
Reference numeral 7 also holds state information indicating whether the apparatus is in the standby state or the viewing state.

Here, the timer unit 219 detects that the set time has arrived, and the time is set based on an instruction from the microcomputer 218.
7. When the clock control unit 217 receives an instruction to set the time from the microcomputer 218, the clock control unit 217 stops the clock supply to the TS decode / descramble unit 120 including the EMM detection unit 112 in the standby state, and the timer unit 219 When the arrival of the set time is detected, the clock supply to the TS decode / descramble unit 120 is started.

The microcomputer 218 executes various programs stored in the memory 115 to
A section for performing overall control of the digital broadcast receiving apparatus 210, a function for setting filter conditions for the TS decode / descramble section 120 and a control for the AV decode section 114, a function for storing viewing results in the IC card 140, A function of controlling each unit in the digital broadcast receiving apparatus 210 in response to a user operation performed through a front panel or a remote control of the digital broadcast receiving apparatus 210, and a content of the EMM when the EMM detecting unit 112 detects the EMM. Has a function of performing various control processes in accordance with the conditions.

Here, the various control processes performed by the microcomputer 218 in accordance with the contents of the EMM include, for example, when the contents of the EMM are information serving as a basis of an encryption key, the information is recorded on the IC card. A cryptographic key is generated by executing a predetermined operation based on the
This is a process to be given to the S-decode descrambler 120. If the content of the EMM is a mail addressed to an individual, this is a process of storing it in the memory 115. If the instruction information is to transmit the information, the information indicating the viewing result stored in the IC card 140 is transmitted to the broadcasting center through the public line network 130 by performing modem control processing and the like via the peripheral I / O unit 116. This is processing to send to. Further, the microcomputer 218 determines which group the own device belongs to from the ID recorded on the IC card, and refers to the time information included in the contents of the EMM to determine which group the own device belongs to. It also performs a process of acquiring the time at which a certain EMM is transmitted and instructing the clock control unit 217 to set the time in the timer unit 219.

<Operation> The operation of digital broadcast receiving apparatus 210 for receiving digital broadcast from digital broadcast transmitting apparatus 200 will be described below. Digital broadcast receiving apparatus 210 is different from Embodiment 1 in FIG.
In addition to the operation of the digital broadcast receiving apparatus 110 shown in FIG. 6, the control operation of stopping and starting the clock supply to the TS decode / descramble section 120 is performed in the standby state.

That is, the digital broadcast receiving apparatus 210
FIG. 5 shows a process of instructing the clock control unit 217 to set the time at which the EMM to which the own apparatus needs to respond by referring to the time information in the EMM to the timer unit 219. Step S in the flowchart
The operation is performed as included in the processing contents of step S22. FIG. 8 is a flowchart showing a timer process executed by the clock control unit 217 when an instruction to set the time is received from the microcomputer 218 to the timer unit 219.

The microcomputer 218 refers to the ID recorded on the IC card and determines, for example, which group the device itself belongs to, such as group A if the ID is even, group B if the ID is odd, and the ID. When an EMM is received, after referring to information other than the time information included in the EMM and performing various control processes according to the information, E
With reference to the time information included in the MM, the time to which the EMM to which the group to which the own device belongs needs to be transmitted is acquired, and the clock control unit 217 is instructed to set the time in the timer unit 219. .

When the microcomputer 218 refers to the time information included in the EMM, if a new EMM has already been received, the microcomputer 218 stops referring to the time information, and returns to the time information other than the time information in the newly received EMM. Perform the processing corresponding to the content,
Thereafter, the time setting is instructed to the clock control unit 217 by referring to the time information in the newly received EMM. The clock control unit 217 is provided from the microcomputer 218 to the timer unit 2.
When an instruction to set the time is received for 19, it is determined whether or not the apparatus is in the standby state based on the state information (step S31).
1) If it is in the standby state, the supply of the clock to the TS decode / descramble unit 120 including the EMM detection unit 112 is stopped (step S312).

The clock control section 217 is connected to the EMM detection section 1
After the clock supply to the TS decode / descramble section 120 including the H.12 is stopped, when it is detected that the time set by the timer section 219 has arrived, that is, an EMM to be received and handled by the own apparatus is transmitted. When the time has arrived (step S313), clock supply to the TS decode / descramble unit 120 including the EMM detection unit 112 is started (step S314).

If the clock control unit 217 is not in the standby state but in the viewing state in step S311, the clock control unit 217 skips the processing in steps S312 to S314. Therefore, in the viewing state, the clock control unit 217 does not stop the clock supply to the TS decode / descramble unit 120. As described above, in the standby state, the digital broadcast receiving apparatus 210 receives the TMM only from the time when the EMM to which the apparatus itself needs to respond is transmitted until the end of the response to the EMM.
The clock is supplied to the S decode / descramble unit 120, and other times, for example, the time when devices belonging to a group different from the group to which the own device belongs need to correspond, are supplied to the TS decode / descramble unit 120. Embodiment 1 In order to stop the operation without supplying the clock, the first embodiment
The power consumption in the standby state is lower than that of the digital broadcast receiving apparatus 110 shown in FIG. << Supplement >> As described above, the digital broadcast receiving apparatus and the digital broadcast transmitting apparatus according to the present invention have been described based on the first and second embodiments. However, the present invention is not limited to these embodiments. Of course. That is, (1) In both embodiments, a method for generating an encryption key in a digital broadcast receiving apparatus is a method for generating an encryption key based on information that is the basis of an encryption key, which is the content of an EMM, and an ID recorded on an IC card. Is used to generate an encryption key for descrambling, but the encryption key is E
Any method may be used as long as it is generated on the basis of the information that is the basis of the encryption key that is the content of the MM. (2) The clock control unit in the digital broadcast receiving apparatus shown in both embodiments operates in the standby state.
When M is detected, the clock supply to the microcomputer is started, and after the microcomputer processes the EMM, the clock supply to the microcomputer is stopped. However, the control of the start and stop of the clock supply to the microcomputer is performed. May be replaced with the control of starting and stopping the supply of power. Also, E
When the microcomputer needs to control the peripheral device to respond to it, such as the instruction information to transmit the information indicating the viewing result to the broadcast center to the broadcasting center, when the microcomputer recognizes the contents of the EMM Accordingly, control may be performed so as to start supplying power to peripheral devices such as a modem, which need to be controlled, and to stop supplying power when the response is completed. (3) The clock control unit in the digital broadcast receiving apparatus shown in both embodiments operates in the standby state.
When M is detected, supply of a clock to the microcomputer is started, and after the microcomputer processes the EMM, the supply of the clock to the microcomputer is stopped. Instead of the stop control, control for increasing or decreasing the clock frequency may be performed. That is, the clock control unit always supplies a clock to the microcomputer,
The frequency of the clock applied to the microcomputer during the period from the completion of the EMM processing until the detection of the next EMM is lower than the frequency of the clock applied to the microcomputer during the processing until the processing of the MM is completed. The control may be performed as follows.

In such a clock frequency control, the microcomputer executes a process corresponding to a user operation and various control processes corresponding to the EMM as separate tasks under the multitask OS even in the standby state. It is effective in such a case. While the EMM is not detected, only the task corresponding to the user operation needs to be operated.
This is because the frequency can be reduced compared to when the operation of the task corresponding to M is necessary. If the clock frequency is reduced, the power consumption of the microcomputer is reduced. (4) In both embodiments, the digital broadcast receiving apparatus receives the digital broadcast via the antenna. However, when the digital broadcast is performed by wire instead of wirelessly, the digital broadcast is received via the cable instead of the antenna. It may be that. (5) In both embodiments, the control of the clock supply to the microcomputer that performs the EMM response processing has been described. However, the EMM here is a control message that is multiplexed and broadcast with program data such as video and audio. This is just one example. This control message may have any data structure as long as it is multiplexed and broadcast together with program data such as moving images and audio. The contents of the control message include, for example, time information for accurately correcting the time of a clock provided in the digital broadcast receiving apparatus, and an electronic program guide (EPG: Electric Program).
The information may be information necessary for drawing mGuide) or control instruction information for forcibly changing the digital broadcast receiving apparatus to a state of viewing an emergency broadcast program of a specific channel in an emergency such as a disaster. When the digital broadcast receiving apparatus receives a control message that is control instruction information in an emergency in the standby state, the digital broadcast receiving apparatus executes a viewing state transition process in response to the control message and transmits an emergency broadcast program of a specific channel. Control to enable viewing may be performed. (6) In the second embodiment, the digital broadcast receiving apparatus sets the digital broadcast receiving apparatus based on the ID recorded on the attached IC card.
For example, the group to which the own device belongs is determined based on whether the ID is an even number or an odd number. However, the grouping method is not limited to this. For example, the area A, the area B, the area C,. Grouping may also be performed according to region and the like. In the case of grouping by area, the digital broadcast transmitting apparatus only needs to sort the EMM to be transmitted for each area, and the digital broadcast receiving apparatus automatically transmits the information indicating the installation area to the user. The group to which the device belongs may be recognized, and the corresponding EMM may be determined. (7) In the second embodiment, all EMMs include the time information. However, not all the EMMs include the time information, and the digital broadcast transmitting apparatus uses the information indicating the scheduled EMM transmission times for a plurality of times. May be transmitted from time to time. For example, the EMM to which the device belonging to the group A corresponds should be sent at a time from just to 200 milliseconds per second and the time from 500 to 700 milliseconds per second, and the EMM to which the device to which the group B belongs should correspond is 200 to 400 milliseconds per second and 700 per second
The digital broadcast transmitting apparatus may occasionally transmit an EMM including information indicating that it is transmitted in a time period from milliseconds to 900 milliseconds. Further, the digital broadcast receiving apparatus may specify the time at which the EMM to be handled by the digital broadcast receiving apparatus is transmitted based on the ID or the like recorded on the IC card. However, no matter what method is used to specify the time at which the EMM to be handled by the own device is transmitted, the digital broadcast receiving device sets the time at which the EMM to be handled by the own device is transmitted to the timer unit. Therefore, in the standby state, it is necessary to supply a clock to the TS decode / descrambling unit only during the corresponding time. (8) In the second embodiment, the clock control unit starts the clock supply to the microcomputer when the EMM is detected. Instead, the clock control unit supplies the clock to the microcomputer when the time set in the timer comes. May also be started.

[0072]

In order to achieve the above object, a digital broadcast receiving apparatus according to the present invention is a digital broadcast receiving apparatus for receiving data which is multiplexed with program data and control messages constituting a broadcast program and is broadcast. Receiving means for receiving data to be broadcast, control message detecting means for detecting that the control message is included in the data received by the receiving means, processing from the first state and the first state. A control message processing unit that takes one of a high-performance second state and executes a control process corresponding to the control message in the second state; and the control message detection unit detects the control message. And a state control means for setting the control message processing means to the second state when the control message processing is performed.

Thus, until a control message such as an EMM is received, the supply of a clock signal to the control message processing means for processing the control message, the supply clock frequency is lowered, or the supply of power is stopped. Even when the operation of the control message processing means is suppressed, when the control message is received, the clock signal supply to the control message processing means is started, the supply clock frequency is increased, or the power supply is started. Since the suppression of the operation is canceled and the control process corresponding to the control message is executed, the power consumption can be reduced easily by adding a simple means for suppressing the operation of the control message processing unit until the control message is received. It can be realized.

Here, the first state is a state in which a clock signal is not supplied, the second state is a state in which a clock signal is supplied, and the state control means includes The supply of a clock signal to the control message processing means may be started when the control message is detected by the message detection means.

Thus, the supply of the clock signal to the control message processing means for processing the control message is stopped until the control message such as the EMM is received, and the operation of the control message processing means is stopped. ,
When the control message is received, the control process corresponding to the control message is executed, so that the operation of the control message processing means is stopped in a period until the control message is received, so that the power consumption can be easily reduced. .

Further, the state control means may further stop supplying a clock signal to the control message processing means after the control message processing means has finished executing the control processing corresponding to the control message. Good. Accordingly, the operation is stopped after the control message processing means completes the execution of the control processing for the received control message, so that the power consumption of the control message processing means can be reduced.

The program data includes compressed moving image data and audio data, and the digital broadcast receiving apparatus further includes moving image data and audio data in the data received by the receiving unit. Video and audio extraction means for extracting the video data and audio data when the clock signal is supplied, and video and audio expansion means for expanding the video and audio data extracted by the video and audio extraction means as long as the clock signal is supplied. A viewing stop instruction receiving unit for receiving a viewing stop instruction by an operation, wherein the state control unit further includes: the moving picture audio decompression unit and the control message processing unit when the viewing stop instruction is received by the viewing stop instruction receiving unit. The supply of the clock signal to the clock signal may be stopped.

Thus, when the user operates a remote controller or the like to give an instruction to stop viewing in order to stop viewing a broadcast program, control message processing means for processing a control message such as EMM and processing of moving image data and audio data are performed. Since the supply of the clock signal to the circuit to be stopped is stopped, it is possible to reduce power consumption in a state in which viewing and listening is not performed, that is, in a standby state.

Further, the digital broadcast receiving apparatus further comprises a viewing start instruction receiving means for receiving a viewing start instruction by a user operation, wherein the control message processing means terminates execution of a control process corresponding to the control message. The stop of the supply of the clock signal by the state control unit is performed only from when the viewing stop instruction is received by the preview stop instruction receiving unit to when the viewing start instruction is received by the preview start instruction receiving unit. The state control means may include the moving picture audio decompression means and the control unit from when the viewing start instruction is received by the viewing start instruction receiving means to when the viewing stop instruction is received by the preview stop instruction receiving means. A clock signal may be supplied to the message processing unit.

Thus, when the user operates a remote controller or the like to give an instruction to start viewing a broadcast program, control message processing means for processing a control message such as an EMM and processing of moving image data and audio data are performed. Since the clock signal is supplied to the circuit that performs the processing, the video data and the audio data can be processed after the standby state is changed to the viewing state, so that the user can view the broadcast program.

Further, the digital broadcast receiving apparatus includes a memory storing a control program for realizing a control process corresponding to the control message, and the control message processing means is a microcomputer for executing the control program. It may be that. Accordingly, in a case where control processing for a control message such as an EMM is realized by software, the start and stop of clock supply of a microcomputer that executes software are controlled.
Unnecessary power consumption can be prevented.

The digital broadcast receiving apparatus may further comprise: at least one channel used by the control message detecting means for detecting the control message; TS decoding means having a plurality of channels to be used, and use of a channel used for the moving picture sound extraction means among channels of the TS decoding means from when the viewing stop instruction is received by the viewing stop instruction receiving means is suppressed. And channel control means for controlling the use of the channel used for the moving picture audio extraction means among the channels of the TS decoding means from when the viewing start instruction is received by the viewing start instruction reception means. And wherein one channel is received by the receiving means. It may be extracts a single type of data matching the preset condition from the data.

Thus, since the number of channels used by the TS decoding means for extracting necessary data from the received data is controlled to be increased or decreased as necessary, unnecessary power consumption can be prevented. The microcomputer is a CPU.
Having a cache, the state control unit further sets the CPU cache to an off state when a viewing stop instruction is received by the viewing stop instruction receiving unit and stops clock supply to the CPU cache,
The CPU cache may be set to the ON state when the viewing start instruction is received by the viewing start instruction receiving means, and clock supply to the CPU cache may be started.

As a result, the CPU cache is used in the viewing state, but the CP is used in the standby state.
Since the operation of the U cache is stopped and the clock supply to the CPU cache is stopped, the power consumption in the standby state can be reduced. The video data and audio data are scrambled and broadcast. The control program includes basic information, the control program calculates the encryption key based on the encryption basic information, and includes a content for causing the microcomputer to execute a control process of supplying the encryption key to the video / audio extraction unit. The extracting means may use the encryption key to extract scrambling applied to the moving image data and the audio data when extracting the moving image data and the audio data.

Thus, even when the microcomputer needs to perform a control process such as calculating an encryption key based on a control message in order to descramble the moving image data and the audio data for viewing, it is necessary and sufficient. Since the stop and start of the clock signal supply are controlled so as to supply the clock signal to the microcomputer or the like, unnecessary power consumption can be prevented.

The control message detecting means detects the control message as long as the clock signal is supplied, and the state control means further detects the control message at a predetermined time. The supply of the clock signal to the control message detection means may be stopped when the supply of the clock signal to the control message detection means is started and the control message processing means completes the execution of the control processing corresponding to the control message. .

Thus, when the time at which the control message is broadcast is determined, the time at which the control message is broadcast is simply determined as a predetermined time. Since the supply of the clock signal is terminated when the signal supply is started and the control processing for the control message is terminated, unnecessary power consumption during the time when the control message is not broadcast can be prevented.

The predetermined time is a time at which a control message that the digital broadcast receiving apparatus needs to respond to is broadcasted, and one or more other digital broadcast receiving apparatuses correspond to the digital broadcast receiving apparatus. The time may be different from the time when the necessary control message is broadcast. Thereby, the control message is broadcast only when the time at which the control message is broadcast is determined as the predetermined time. This makes it possible to prevent unnecessary power consumption during the operation.

Further, the digital broadcast receiving apparatus includes IC card reading means for reading identification information from an IC card on which identification information is recorded, and the state control means includes:
The predetermined time may be determined according to the identification information recorded on the IC card. Accordingly, the predetermined time is calculated based on the identification information recorded on the IC card mounted on the digital broadcast receiving device. Therefore, when the digital broadcast receiving device can be divided into groups by the identification information, the digital broadcast receiving device belongs to each group. If the digital broadcast receiving apparatus broadcasts a control message that must be handled at a different time for each group, when the control message that the digital broadcast receiving apparatus needs to handle is broadcast, the control message is detected. Operation of the control message detecting means can be started, so that unnecessary power consumption can be prevented while the control message to be handled by the own device is not broadcast.

Further, the data received by the receiving means further includes time information for specifying the predetermined time, and the state control means controls the state control means in accordance with the identification information based on the time information. The determination of the predetermined time may be performed. As a result, information for specifying the broadcast time of the control message to be handled by each digital broadcast receiving apparatus is broadcast from the digital broadcast transmitting apparatus side, and each digital broadcast receiving apparatus is used to determine each digital broadcast information based on the identification information recorded on the IC card. The broadcast receiving apparatus prevents unnecessary power consumption until the control message to which the own device responds is broadcast even when the predetermined time at which the control message to which the own device responds is broadcast is determined. be able to.

The first state is a state where power is not being supplied, the second state is a state where power is being supplied, and the state control means is a control message detection means. The power supply to the control message processing means may be started when the control message is detected. As a result, until the control message such as the EMM is received, the supply of power to the control message processing means for performing control processing in response to the control message is stopped, and the operation of the control message processing means is stopped. Also, when the control message is received, the control process corresponding to the control message is executed, so that the power consumption can be easily reduced in a period until the control message is received.

The digital broadcast receiving apparatus is connected to a peripheral device, the control message is information for controlling the peripheral device, and the first state is receiving a clock signal. The second state is a state in which a clock signal is supplied, and the control message processing means controls the peripheral device in response to the control message in the second state. Performing a process, wherein the state control means includes:
When the control message is detected by the control message detecting means, the control message processing means starts supplying a clock signal to the control message processing means and starts supplying power to the peripheral device. The supply of the clock signal to the control message processing means may be stopped and the supply of power to the peripheral device may be stopped when the execution of the control process corresponding to the above is completed.

Thus, when a control message such as an EMM containing an instruction to control the modem and send the viewing result to the broadcasting center is received, power is supplied to the peripheral device such as the modem only when necessary. In addition, it is possible to reduce the power consumption of the entire digital broadcast receiving system including peripheral devices. The digital broadcast receiving apparatus further includes a memory for storing a control program for causing a microcomputer to execute a control process corresponding to the control message and another process as separate tasks by multitask control, and the first state is , A state in which a clock signal having a first frequency is supplied, and the second state is a state in which a clock signal having a second frequency higher than the first frequency is being supplied. ,
A microcomputer that executes the control program, wherein the state control means sends a second message to the microcomputer from a time when the control message is detected by the control message detection means.
A clock signal of a frequency may be supplied, and the microcomputer may supply the clock signal of the first frequency to the microcomputer when the microcomputer finishes executing the control process corresponding to the control message.

Thus, when the microcomputer executes a task for processing corresponding to a user operation with a remote controller or the like and a task for processing a control message under multitask control, the control message is received. Until the execution, the task for processing the control message is in a standby state, so that the execution speed of the microcomputer can be reduced by that much, and the power consumption of the microcomputer can be reduced by this reduction in speed.

[0095] The state control means may further set the control message processing means to the first state when the control message processing means has finished executing the control processing corresponding to the control message. This suppresses the operation of the control message processing unit after the control message processing unit completes the execution of the control process for the received control message, so that the power consumption of the control message processing unit can be reduced.

Also, a digital broadcast transmitting apparatus according to the present invention is a digital broadcast transmitting apparatus for transmitting data including a control message by a digital broadcast system, wherein each of a plurality of control messages is transmitted to a plurality of digital broadcast receiving apparatuses. Control message classifying means for classifying the digital broadcast receiving apparatuses into groups to which control processing corresponding to the control message belongs when the digital broadcast receiving apparatuses are classified into a plurality of groups; Control message transmitting means for transmitting the generated control messages at different times, and time information indicating the time at which the control message transmitting means transmits the control messages of each group, prior to the transmission of the control message. Information transmission means. The features.

[0097] Thereby, the digital broadcast transmitting apparatus receives the digital broadcast transmitted by the digital broadcast transmitting apparatus, and each digital broadcast receiving apparatus belonging to each group specifies, from the time information, the time at which the control message corresponding to the own apparatus is broadcast. The circuit for detecting a control message or the like can be stopped until that time, so that power consumption can be suppressed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a digital broadcast transmission / reception system according to a first embodiment.

FIG. 2 is a configuration diagram of a TS decoding / descrambling unit 120 including an EMM detection unit 112.

FIG. 3 is a diagram showing a data structure of a TS packet.

FIG. 4 is a flowchart illustrating a standby state transition process.

FIG. 5 is a flowchart showing an EMM process performed by the digital broadcast receiving apparatus 110 when the EMM detection unit 112 detects an EMM.

FIG. 6 is a flowchart showing a viewing state transition process.

FIG. 7 is a configuration diagram of a digital broadcast transmission / reception system according to a second embodiment.

FIG. 8 is a flowchart illustrating a timer process executed by a clock control unit 217 when an instruction to set a time is received from a microcomputer 218 to a timer unit 219.

FIG. 9 is a schematic configuration diagram of a conventional digital broadcast transmission / reception system.

[Explanation of symbols]

 100, 200 Digital broadcast transmitting apparatus 101 Broadcast management section 102 Program transmitting section 103 EPG transmitting section 104, 204 Limited reception information transmitting section 105 Subscriber information managing section 106 Encoder section 110, 210 Digital broadcast receiving apparatus 111 Front end section 112 EMM detection Unit 113 DMA control unit 114 AV decoding unit 115 Memory 116 Peripheral I / O unit 117, 217 Clock control unit 118, 218 Microcomputer 120 TS decode / descramble unit 140 IC card 207 Transmission destination management unit 219 Timer unit

Claims (29)

[Claims] 1. A digital broadcast receiving apparatus for receiving broadcast data in which program data and control messages constituting a broadcast program are multiplexed, comprising: receiving means for receiving broadcast data; A control message detection means for detecting that the control message is included in the received data; and a second state having a first state and a second state having a higher processing capacity than the first state. Control message processing means for executing a control process corresponding to the control message in the state; and controlling the control message processing means from the time when the control message is detected by the control message detection means.
A digital broadcast receiving apparatus comprising: state control means for setting a state. 2. The first state is a state in which a clock signal is not supplied. The second state is a state in which a clock signal is supplied. 2. The digital broadcast receiving apparatus according to claim 1, wherein supply of a clock signal to said control message processing means is started when said control message is detected by said detection means. 3. The state control means further stops supplying a clock signal to the control message processing means after the control message processing means completes execution of a control process corresponding to the control message. The digital broadcast receiving apparatus according to claim 2, wherein 4. The program data includes compressed moving image data and audio data, and the digital broadcast receiving apparatus further includes moving image data and audio data in the data received by the receiving unit. Video and audio extraction means for extracting the video data and audio data when the clock signal is supplied; and video and audio expansion means for expanding the video and audio data extracted by the video and audio extraction means as long as the clock signal is supplied. A viewing stop instruction receiving unit for receiving a viewing stop instruction by an operation, wherein the state control unit further includes the moving picture audio decompression unit and the control message processing unit from when the viewing stop instruction is received by the viewing stop instruction receiving unit. 4. A digital broadcast receiving apparatus according to claim 3, wherein supply of a clock signal to the digital broadcast receiving apparatus is stopped. . 5. The digital broadcast receiving apparatus further comprises:
And a viewing start instruction receiving means for receiving a viewing start instruction by a user operation, wherein the supply of the clock signal is stopped by the state control means when the control message processing means has finished executing the control processing corresponding to the control message. Is performed only during a period from when the viewing stop instruction is received by the preview stop instruction receiving unit to when a viewing start instruction is received by the preview start instruction receiving unit, and the state control unit receives the viewing start instruction. Supplying a clock signal to the video / audio decompression means and the control message processing means from when the viewing start instruction is received by the means to when the viewing stop instruction is received by the preview stop instruction receiving means. 5. The digital broadcast receiving apparatus according to claim 4, wherein: 6. The digital broadcast receiving device includes a memory storing a control program for implementing a control process corresponding to the control message, and the control message processing unit is a microcomputer that executes the control program. The digital broadcast receiving apparatus according to claim 5, wherein: 7. The digital broadcast receiving apparatus according to claim 1, wherein one or more channels used by the control message detecting means to detect the control message, and the moving picture sound extracting means extract the moving picture data and the sound data. A TS decoding unit having a plurality of channels to be used, and a use of a channel used for the video / audio extraction unit among the channels of the TS decoding unit from when the viewing stop instruction is received by the viewing stop instruction receiving unit is suppressed. And channel control means for controlling the use of the channel used for the moving picture audio extraction means among the channels of the TS decoding means from when the viewing start instruction is received by the viewing start instruction reception means. Where one channel is the data received by the receiving means. 7. The digital broadcast receiving apparatus according to claim 6, wherein one kind of data meeting a preset condition is extracted from the data. 8. The microcomputer has a CPU cache, and the state control means sets the CPU cache to an off state when the viewing stop instruction is received by the viewing stop instruction receiving means, and sets the CPU cache to an off state. When the viewing start instruction is received by the viewing start instruction receiving means, the clock is stopped.
The PU cache is set to the ON state and the CP
7. The digital broadcast receiving apparatus according to claim 6, wherein clock supply to the U cache is started. 9. The video data and audio data are scrambled and broadcast, and the control message is a basis for calculating an encryption key used to descramble the video data and audio data. The control program includes a content for causing the microcomputer to execute a control process of calculating the encryption key based on the encryption basic information and supplying the encryption key to the video / audio extraction unit, 7. The digital broadcast according to claim 6, wherein the video / audio extraction unit de-scrambles the video / audio data using the encryption key when extracting the video / audio data. Receiver. 10. The control message detection means detects the control message as long as a clock signal is supplied, and the state control means further detects the control message when a predetermined time comes. Start supplying the clock signal to the means,
7. The digital broadcast receiving apparatus according to claim 6, wherein the supply of the clock signal to the control message detecting means is stopped when the control message processing means has finished executing the control processing corresponding to the control message. 11. The digital broadcast receiving device includes a memory storing a control program for implementing a control process corresponding to the control message, and the control message processing unit is a microcomputer that executes the control program. The digital broadcast receiving apparatus according to claim 3, wherein: 12. The digital broadcast receiving device, comprising: a moving image / audio extracting unit that extracts moving image data and audio data when the data received by the receiving unit includes the moving image data and the audio data; A video / audio decompression unit for decompressing the extracted video data and audio data, a viewing stop instruction receiving unit for receiving a viewing stop instruction by a user operation, a viewing start instruction receiving unit for receiving a viewing start instruction by a user operation, and the control message TS decoding means having one or more channels used by the detection means to detect the control message, and a plurality of channels used by the video / audio extraction means to extract the video data and audio data; The TS decoding starts when the viewing start instruction is received by the instruction receiving means. The use of the channel used for the video / audio extraction unit among the channels provided by the video decoding unit is suppressed, and when the viewing start instruction is received by the viewing start instruction receiving unit, the video audio / video is selected from the channels provided by the TS decoding unit. Channel control means for controlling use of a channel used for the extraction means, wherein one channel is one kind of data received by the reception means and which satisfies a preset condition. 12. The method according to claim 11, wherein data is extracted.
Digital broadcast receiver according to the above. 13. The digital broadcast receiving apparatus comprising: a moving image / audio extracting unit that extracts moving image data and audio data when the data received by the receiving unit includes the moving image data and the audio data; Video and audio data expansion means for expanding the extracted video and audio data, wherein the video data and audio data are scrambled and broadcast, and the control message is applied to the video data and audio data. The control program calculates the encryption key based on the encryption basic information, and sends the encryption key to the video / audio extraction unit. The microcomputer includes a step of causing the microcomputer to execute a control process of supplying the moving image data and the sound. 12. The digital broadcast receiving apparatus according to claim 11, wherein, when extracting voice data, the scramble applied to the moving image data and the audio data is released using the encryption key. 14. The control message detection means detects the control message as long as a clock signal is supplied, and the state control means further detects the control message when a predetermined time comes. Start supplying the clock signal to the means,
12. The digital broadcast receiving apparatus according to claim 11, wherein the supply of the clock signal to the control message detecting means is stopped when the control message processing means has finished executing the control processing corresponding to the control message. 15. The predetermined time is a time at which a control message that the digital broadcast receiving apparatus needs to respond to is broadcast, and one or more other digital broadcast receiving apparatuses correspond to the digital broadcast receiving apparatus. 15. The digital broadcast receiving apparatus according to claim 14, wherein the time is different from a time at which a necessary control message is broadcast. 16. The digital broadcast receiving apparatus further comprises: IC card reading means for reading identification information from an IC card in which the identification information is recorded; The digital broadcast receiving apparatus according to claim 15, wherein the predetermined time is determined according to the time. 17. The data received by the receiving unit further includes time information for specifying the predetermined time, and the state control unit, based on the time information, 17. The digital broadcast receiving apparatus according to claim 16, wherein a predetermined time is determined. 18. The digital broadcast receiving device includes a memory storing a control program for implementing a control process corresponding to the control message, and the control message processing unit is a microcomputer that executes the control program. 3. The digital broadcast receiving device according to claim 2, wherein: 19. The control message detecting means detects the control message as long as a clock signal is supplied, and the state control means further detects the control message at a predetermined time. Start supplying the clock signal to the means,
19. The digital broadcast receiving apparatus according to claim 18, wherein the supply of the clock signal to the control message detecting means is stopped when the control message processing means has finished executing the control processing corresponding to the control message. 20. The digital broadcast receiving apparatus comprising: a moving image / audio extracting unit that extracts moving image data and audio data when the data received by the receiving unit includes moving image data and audio data; Video and audio decompression means for decompressing the extracted video and audio data, wherein the video and audio data are scrambled and broadcast, and the control message is applied to the video and audio data The control program calculates the encryption key based on the encryption basic information, and sends the encryption key to the video / audio extraction unit. The microcomputer includes a step of causing the microcomputer to execute a control process of supplying the moving image data and the sound. 3. The digital broadcast receiving apparatus according to claim 2, wherein the scramble applied to the moving image data and the audio data is released using the encryption key when extracting the voice data. 21. The first state is a state where power is not supplied, the second state is a state where power is supplied, and the state control unit is the control message detection unit. 2. The digital broadcast receiving apparatus according to claim 1, wherein when the control message is detected, power supply to the control message processing means is started. 22. The digital broadcast receiving device includes a memory storing a control program for implementing a control process corresponding to the control message, and the control message processing unit is a microcomputer that executes the control program. 22. The digital broadcast receiving device according to claim 21, wherein: 23. The state control unit further comprising: stopping supply of power to the control message processing unit when the control message processing unit has finished executing a control process corresponding to the control message. 23. The digital broadcast receiving apparatus according to claim 22, wherein: 24. The digital broadcast receiving device is connected to a peripheral device, the control message is information for controlling the peripheral device, and the first state is receiving a clock signal. The second state is a state where a clock signal is supplied, and the control message processing means controls the peripheral device in the second state in response to the control message. The state control means starts supplying a clock signal to the control message processing means when the control message is detected by the control message detection means, and supplies power to the peripheral device. Supply is started and the control message processing means starts executing the control message corresponding to the control message. Claim, characterized in that stops power supply to the peripheral device stops the supply of the clock signal to di processing means 1
Digital broadcast receiver according to the above. 25. The digital broadcast receiving apparatus, further comprising: a memory storing a control program for causing a microcomputer to execute a control process corresponding to the control message and another process as separate tasks by multitask control, and The first state is a state in which a clock signal of a first frequency is supplied, the second state is a state in which a clock signal of a second frequency higher than the first frequency is supplied, and the control message The processing means is a microcomputer for executing the control program, and the state control means supplies a clock signal of a second frequency to the microcomputer from the time when the control message is detected by the control message detection means, From the end of execution of the control process corresponding to the control message to the microcomputer. Digital broadcasting receiver according to claim 1, wherein the supplying the clock signal. 26. The program data includes compressed moving image data and audio data, and the digital broadcast receiving apparatus further includes moving image data and audio data in the data received by the receiving unit. Video and audio extraction means for extracting the video data and audio data when the clock signal is supplied; and video and audio expansion means for expanding the video and audio data extracted by the video and audio extraction means as long as the clock signal is supplied. A viewing stop instruction receiving means for receiving a viewing stop instruction by an operation, and the state control means further stops supply of a clock signal to the video / audio extending means from when the viewing stop instruction is received by the viewing stop instruction receiving means. And supplying the clock signal of the first frequency to the microcomputer. Digital broadcasting receiver according. 27. The digital broadcast receiving apparatus further includes a viewing start instruction receiving unit that receives a viewing start instruction by a user operation, and the state control unit further receives a viewing start instruction by the viewing start instruction receiving unit. 27. The digital broadcast receiving apparatus according to claim 26, wherein the supply of a clock signal to said moving picture audio decompression means is started at a time, and a clock signal of said second frequency is supplied to said microcomputer. 28. The state control means further sets the control message processing means to the first state when the control message processing means completes execution of a control process corresponding to the control message. Item 2. The digital broadcast receiving device according to Item 1. 29. A digital broadcast transmitting apparatus for transmitting data including a control message by a digital broadcasting system, wherein each of the plurality of control messages is classified into a plurality of groups of a plurality of digital broadcast receiving apparatuses receiving the digital broadcast. Control message classifying means for classifying into groups to which a digital broadcast receiving apparatus to perform control processing corresponding to the control message belongs, and transmitting the control messages classified into different groups by the control message classifying means at different times. Control message transmitting means, and time information indicating time when the control message transmitting means transmits the control message of each group, time information transmitting means for transmitting the control message prior to the transmission of the control message. Digital broadcast transmitter.