JP6450974B2 - Reception device, reception method, and reception program - Google Patents

Description

  The present invention relates to a receiving device, a receiving method, and a receiving program.

  In 4K / 8K ultra-high-definition television broadcasting (4K / 8K UHDTV: Ultra High Definition Television), the content of a broadcast program is received via a reception processing facility. The content of the broadcast program is carried using an IF signal obtained by converting the frequency band of the broadcast wave received from the broadcast satellite by the reception processing facility into a predetermined intermediate frequency (IF) band. The frequency band of the IF signal is different from conventional BS (Broadcasting Satellite) broadcasting. For this reason, broadcast program content may not be received unless a reception processing facility compatible with 4K / 8K UHDTV is provided. Conventionally, a receiving apparatus having a function of estimating a factor that a satellite broadcast cannot be received has been proposed. For example, Patent Literature 1 describes a broadcast signal receiving apparatus that determines whether or not a reception condition of a satellite SN (Signal-to-Noise Ratio) is satisfied when performing a channel scan of terrestrial digital broadcasting.

  On the other hand, in digital television broadcasting, a conditional access system (CAS) is introduced in order to protect content constituting a broadcast program. CAS is a technology for preventing viewing of broadcast programs and unauthorized duplication of broadcast programs by parties other than legitimate subscribers using encryption technology. As one method for realizing the CAS function, the broadcaster transmits a CAS program for decrypting the encrypted content to the receiving device. In order to increase the degree of protection, the CAS program may be updated. In addition, contracts required for viewing broadcast programs are independent for each broadcaster, and contract conditions such as whether or not there is a charge may differ. Therefore, there is a possibility that different CAS programs are used depending on broadcasters.

JP 2012-44464 A

  The receiving apparatus may not be able to present the content of the received broadcast program without using a CAS program within a valid period (for example, the latest version) that matches the selected channel. For this reason, simply analyzing the characteristics of the received signal may not immediately identify the cause of failure to obtain information transmitted on broadcast waves, such as broadcast program content.

The present invention has been made to solve the above problems, and one aspect of the present invention includes a signal state determination unit that determines the state of a received signal received for each channel, and a cipher carried by the received signal and encrypted. and determining program determining unit decoding status is success or failure of decoding for reduction has been limited receiving system program, on the basis of the state of the received signal of each channel to the decoding state of the conditional access system program, consisting of a plurality of channels e Bei a reception state determining unit determines the reception state of each channel group, and the reception state determination unit, limited reception state to a channel group including a good plurality of channels than the predetermined state, that is successfully decoded receiving apparatus determines whether included both conditional access system program to decode the channel have failed according to the reception system program A.

  ADVANTAGE OF THE INVENTION According to this invention, the cause which cannot acquire the information transmitted with a broadcast wave can be estimated efficiently.

It is a block diagram which shows the structure of the broadcast system which concerns on this embodiment. It is a block diagram which shows the structure of the transmitter which concerns on this embodiment. It is a figure which shows the example of network information. It is a figure which shows the example of a satellite distribution system descriptor. It is a figure which shows the example of DAM. It is a figure which shows the example of a compatibility descriptor. It is a figure which shows the example of MH-SDTT. It is a figure which shows the example of a MPU download content descriptor. It is a figure which shows the example of MH-network download content descriptor. It is a block diagram which shows the structure of the receiver which concerns on this embodiment. It is a block diagram which shows the structure of the control part which concerns on this embodiment. It is a flowchart which shows the reception process which concerns on this embodiment. It is a figure which shows the example of the reception status list | wrist which concerns on this embodiment. It is a figure which shows the example of a display which concerns on the reception process which concerns on this embodiment. It is a figure for demonstrating the determination process of the reception state which concerns on this embodiment. It is a figure which shows the example of the message screen which concerns on this embodiment. It is a figure which shows the example of the error screen which concerns on this embodiment. It is a figure which shows the other example of the error screen which concerns on this embodiment.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of a broadcasting system 1 according to the present embodiment. The broadcast system 1 includes a plurality of transmission devices 11, a plurality of server devices 21, a reception processing facility 31, and a reception device 41.

The transmission device 11 and the server device 21 are installed for each broadcaster.
The reception processing equipment 31 may be installed in each home or business office, but is not limited thereto, and may be installed for each facility or for each set of a plurality of facilities.
The reception device 41 receives a broadcast program broadcast from the transmission device 11 via the reception processing facility 31. The receiving device 41 displays the video of the received broadcast program and reproduces the sound of the broadcast program. The receiving device 41 is a television receiver installed in each home or business office.

  The transmission device 11 transmits multiplexed data obtained by multiplexing various types of data for each uplink transmission channel to the reception processing facility 31 as an uplink broadcast wave via the broadcast transmission path 12. The polarization direction of the broadcast wave may differ depending on the group of frequency bands to which the frequency band of the uplink transmission channel belongs. As the polarization direction, for example, whether vertical polarization or horizontal polarization is used is determined in advance.

Examples of data to be multiplexed include program data, notification information, control information, and CAS programs. Program data is data indicating the contents of a broadcast program. The notification information is information indicating the distribution condition of the CAS program. The control information is information for demultiplexing (separating) various types of information multiplexed on the broadcast transmission path 12 in the receiving device 41.
The CAS program is a computer program for realizing part or all of the CAS function. The purpose of the transmission of the CAS program is to update the existing CAS program used in the receiving device 41. The CAS program is updated in order to prevent damage caused by decryption even if the encrypted data by CAS is decrypted.
Identification information for identifying each CAS program is given to the CAS program. This identification information may include, for example, a CAS program identifier (CAS-ID) indicating a series of CAS program series (CAS-ID) and a version number (CAS-Ver) indicating a version related to the system. In general, the higher the version number, the newer the version. The receiving apparatus 41 of a regular contractor can receive the latest CAS program at that time, and can view broadcast programs using the CAS program received within the valid period up to that time, including the latest one. To. The CAS program is not necessarily common to all channels. The CAS program may be different for each channel, and may be common among a plurality of channels. A system (series) of CAS programs different between channels may be identified by a CAS program identifier (CAS-ID). The identification information, CAS-ID, and CAS-Ver described above correspond to ARIB STD-B61 (Association of Radio Industries and Business Standards B61) version 1.0 standard document, respectively, and CA_program_ID, CAS program ID, and version, respectively. . In the following description, the case where the identification information is represented by CAS-ID and CAS-Ver is taken as an example, but the identification information is not limited to this as long as it can uniquely identify the CAS program.

  The broadcast transmission path 12 is a transmission path for unidirectionally transmitting broadcast waves transmitted from the transmission apparatus 11 to a plurality of reception apparatuses 41 simultaneously. The broadcast transmission path 12 includes a relay device (not shown) loaded on the artificial satellite 13. The artificial satellite 13 includes a broadcasting satellite (BS) dedicated to broadcasting and a communication satellite (CS) used for communication. Whether to use BS or CS is predetermined according to the frequency band group to which the frequency band of the uplink transmission channel belongs.

The relay device shifts the frequency of the upstream broadcast wave received from the transmission device 11. The relay device shifts the frequency band. The relay device has a shifted frequency band component and generates right-handed circularly polarized wave or left-handed circularly polarized wave as a downstream broadcast wave carrying data carried by the upstream broadcast wave. Whether to use right-handed circularly polarized wave or left-handed circularly polarized wave is predetermined according to the frequency band group to which the frequency band of the downstream transmission channel corresponding to the upstream transmission channel belongs. In order to avoid interference between the upstream broadcast wave and the downstream broadcast wave, each frequency band of the upstream transmission channel and each frequency band of the downstream transmission channel are different from each other.
Note that a part of the broadcast transmission path 12 may include a communication line, for example, a communication line from the transmission device 11 to a transmission facility for transmitting radio waves. In the following description, transmission (transmission, reception) of various data via the broadcast transmission path 12 may be referred to as “transmission (transmission, reception, or download) by broadcasting”.

  The server device 21 is a server device that stores newly acquired software. The location of the server device 21 is notified to the receiving device 41 via the broadcast transmission path 12 as a URL (Uniform Resource Locator) as an element of notification information. When the server apparatus 21 receives the request signal from the receiving apparatus 41, the server apparatus 21 transmits, to the receiving apparatus 41, distribution data in which the CAS-ID and CAS-Ver CAS program specified by the request signal are stored as a response.

  The communication transmission path 22 is a transmission path for bidirectionally transmitting various data between the server device 21 and the receiving device 41. The communication transmission path 22 includes, for example, a wide area communication network such as the Internet having a wired large-capacity backbone network. The communication transmission path 22 may be a communication network including a wireless access network in part, for example, a public wireless communication network. Note that transmission (transmission, reception) of various data via the communication transmission path 22 may be referred to as “transmission (transmission, reception, or download) via communication”.

  The reception processing facility 31 generates an intermediate frequency (IF) signal by down-converting an antenna that receives a downlink broadcast wave from the broadcast transmission path 12 and a received signal from the received downlink broadcast wave at a predetermined local frequency. A converter is provided. The reception processing facility 31 outputs the generated IF signal to the reception device 41 connected to the own facility. The reception processing facility 31 is, for example, a one-line wiring system that transmits a received IF signal to a plurality of receiving apparatuses using a single cable. In the reception processing facility 31, the antenna and the converter may be configured separately. Further, a wiring member such as a booster, a distributor, or an antenna plug (so-called TV outlet) may be interposed between the reception processing facility 31 and the reception device 41.

  The antenna included in the reception processing facility 31 is, for example, a parabolic antenna. Convert the right-handed circularly polarized wave component and the left-handed circularly polarized wave component into IF signals so that the frequency band of the right-handed circularly polarized wave component and the left-handed circularly polarized wave component do not overlap each other. Therefore, the local frequency used is different. In addition, the local frequency differs between the BS and the CS so that the frequency band after conversion of the received signal received from the BS and the frequency band after conversion of the received signal received from the CS do not overlap each other. The frequency bands of the respective polarization components after being converted into IF signals are classified as different physical channels. Each physical channel is uniquely associated with an upstream transmission channel and a downstream transmission channel. In the following description, the converted frequency band and intermediate frequency are referred to as IF frequency band and IF intermediate frequency, respectively. In addition, the component of the IF frequency band of each physical channel may be simply referred to as an IF signal.

  The reception device 41 determines the state of the IF signal input from the reception processing facility 31 as the reception signal received for each channel from the transmission device 11, and determines the decoding state of the CAS program carried by the reception signal. The receiving device 41 determines the broadcast reception state between channels based on the IF signal state for each physical channel and the decoding state of the CAS program, and displays a message screen as notification information regarding the determined reception state.

(Configuration of transmitter)
Next, the configuration of the transmission device 11 according to the present embodiment will be described.
FIG. 2 is a block diagram illustrating a configuration of the transmission device 11 according to the present embodiment. The transmission device 11 includes a program acquisition unit 111, a program data acquisition unit 112, a notification information acquisition unit 113, a control information acquisition unit 114, a multiplexing unit 115, and a modulation unit 116. An antenna 117 is connected to the transmission device 11.

  The program acquisition unit 111 acquires distribution data in a predetermined format storing security information necessary for decryption of the latest version of the CAS program and a CAS program encrypted using a predetermined encryption method at that time (current). To do. The predetermined encryption method is, for example, AES (Advanced Encryption Standard). The predetermined format data is, for example, section format data. The security information includes common information (DCM: Download Control Message) and individual information (DMM: Download Management Message) shared between the receivers 41 of the receivers who have signed a regular reception contract with the broadcaster. . The common information (DCM) is information common to the receiving device 41, and the individual information (DMM) is information that differs depending on each receiving device 41. The program acquisition unit 111 transmits the acquired distribution data to the broadcast transmission path 12 via the multiplexing unit 115 in a predetermined method, for example, a data carousel method. The data carousel method is a method of repeatedly transmitting the same data for a certain period.

  Specifically, the program acquisition unit 111 divides the divided data obtained by dividing the input CAS program and security information into predetermined sizes as MPU (Media Processing Unit). The divided data is sequentially stored in the MPU in ascending order of individual MPU sequence numbers. In addition, the program acquisition unit 111 generates MPU configuration information as a data asset management table (DAM: Data Asset Management Table). Distribution data is formed by the generated DAM and MPU. The DAM includes CAS-ID and CAS-Ver.

  Program data is input to the program data acquisition unit 112. The program data is data including video data and audio data representing a broadcast program. The program data is encrypted using a predetermined encryption method and encryption key corresponding to the decryption method and decryption key used in the decryption process by the CAS program to be transmitted. These decryption keys are transmitted as part of the security information included in the distribution data. The program data acquisition unit 112 converts the input program data into data in a predetermined format, for example, MMT (MPEG: Moving Picture Expert Media Transport) format, and outputs the converted program data to the multiplexing unit 115.

  The notification information acquisition unit 113 receives notification information regarding CAS program download. The notice information includes CAS-ID and CAS-Ver as information for specifying the CAS program. Further, the notification information includes a distribution time, an address of the server device 21 that is a separate distribution source, a priority of the distribution source, that is, a reception (download) route, and the like. The notification information is represented by, for example, a section format table, MH-SDTT (Software Download Trigger Table). The notification information acquisition unit 113 outputs the acquired notification information to the multiplexing unit 115.

  Control information for receiving and separating the above-described data by the receiving device 41 is input to the control information acquisition unit 114. The control information includes network information. The network information includes physical conditions such as the frequency (frequency) and polarization (polarization) of the downstream broadcast wave transmitted through the broadcast transmission path 12. The control information is represented by, for example, a network information table (TLV_Network_Information Table ()) for TLV (Type Length Value). The control information acquisition unit 114 outputs the acquired control information to the multiplexing unit 115.

  The multiplexing unit 115 receives distribution data input from the program acquisition unit 111, program data input from the program data acquisition unit 112, notification information input from the notification information acquisition unit 113, and control information acquisition unit 114. The control information is multiplexed to generate multiplexed data in a predetermined format (for example, TLV format). The multiplexing unit 115 outputs the generated multiplexed data to the modulation unit 116.

The modulation unit 116 modulates the multiplexed data input from the multiplexing unit 115 using a predetermined modulation method (for example, APSK: Amplitude Phase Shift Keying (amplitude phase displacement modulation)). The modulation unit 116 performs, for example, error detection coding and interleaving as preprocessing before modulation. The modulation unit 116 reinforces resistance to noise and code errors by performing preprocessing. In error detection coding, the modulation unit 116 performs, for example, BCH (Bose Chaudhuri Hocquechem) coding and LDPC (Low-density Parity-check Code) coding. Interleaving is a process of rearranging the order of bit strings constituting data in a predetermined order.
The modulation unit 116 up-converts the modulated multiplexed data with the carrier frequency of the uplink transmission channel to generate a transmission signal of the uplink transmission channel. Modulation section 116 outputs the generated transmission signal to antenna 117.

  The antenna 117 transmits the transmission wave of the uplink transmission channel based on the transmission signal input from the modulation unit 116.

(Data structure of network information)
Next, examples of network information related to distribution of various types of information will be described.
FIG. 3 is a diagram illustrating an example of network information. In the example shown in FIG. 3, the network information is represented by a network information table for TLV. The TLV network information table may include a descriptor area (descriptor ()) for each TLV stream identification (tlv_stream_id). Here, the uplink transmission channel is identified by the TLV stream identification. Since the uplink transmission channel corresponds to the downlink transmission channel, the reception device 41 can identify the downlink transmission channel by the TLV stream identification. In the descriptor area (descriptor ()), a satellite distribution system descriptor (Satelite_Delivery_System_Descriptor ()) is described.

(Data structure of satellite distribution system descriptor)
Next, the data structure of the satellite distribution system descriptor will be described.
FIG. 4 is a diagram illustrating an example of a satellite distribution system descriptor. In the example shown in FIG. 4, the satellite distribution system descriptor includes a frequency and a polarization. In the frequency, the center frequency of each downlink transmission channel is described. In the polarization, a value indicating the polarization characteristic is described. For example, “10” and “11” are values indicating left-hand circular polarization and right-hand circular polarization, respectively.

(Data structure of DAM)
Next, an example of DAM used for software transmission will be described.
FIG. 5 is a diagram illustrating an example of the DAM. The DAM has a descriptor area (descriptor ()), and the area includes a compatibility descriptor (compatibilityDescriptor ()).

(Compatibility descriptor data structure)
Next, the data structure of the compatibility descriptor will be described. The compatibility descriptor (compatibilityDescriptor ()) describes detailed information that cannot be represented by the table identification (table_id) or group area (group) of DAM or MH-SDTT.
FIG. 6 is a diagram illustrating an example of the compatibility descriptor. In the example illustrated in FIG. 6, the compatibility descriptor includes a model (model), a version (version), and supplementary information (additionalInformation). For example, the CAS-ID is described in the model and the Ver-ID is described in the version. Further, in the supplementary information (additionalInformation), a signature value (described later) of the CAS program is described.

(Data structure of notification information)
Next, the data structure of MH-SDTT representing the notification information acquired by the notification information acquisition unit 113 will be described.
FIG. 7 is a diagram illustrating an example of MH-SDTT. In the example illustrated in FIG. 7, the MH-SDTT includes a table identification extension (table_id_extension), a target version (target_version), a new version (new_version), a download level (download_level), a version indication (version_indicator), a version number (version), and a start time. (Start_time), distribution duration (duration), and descriptor area (descriptors ()).

In the table identification extension (table_id_extension), for example, CAS-ID is described.
The target version (target_version) describes the CAS-Ver of the CAS program to be updated. In the new version (new_version), for example, CAS-Ver of the CAS program transmitted by the transmission apparatus 11 is described.
In the download level (download_level), a value indicating a download mode is stored. For example, “01” indicates forced download, and “00” indicates optional download.
The version instruction (version_indicator) indicates the range of versions to be updated. '00' indicates all versions, and '03' indicates only the specified version.

The start time (start_time) indicates a time at which the transmission apparatus 11 starts transmission of software.
The distribution continuation time (duration) indicates a time during which the transmission device 11 continues to transmit software. In one MH-SDTT, a plurality of start times (start_time) and distribution duration (duration) can be set.
In the descriptor area (descriptors ()), an MPU download content descriptor and an MH-network download content descriptor are described.

(Data structure of MPU download content descriptor)
Next, the data structure of the MPU download content descriptor will be described.
FIG. 8 is a diagram illustrating an example of the MPU download content descriptor. The MPU download content descriptor includes a compatibility flag (compatibility_flag), a compatibility descriptor (compatibilityDescriptor ()), an item number (num_of_items), an item identification (item_id), an item size (item_size), and a private data area te_pati including.

  The compatibility flag (compatibility_flag) is a flag indicating the presence / absence of a compatibility descriptor (compatibilityDescriptor ()). The compatibility descriptor (compatibilityDescriptor ()) includes the same content as the above-described compatibility descriptor (FIG. 6). Here, CAS-ID and CAS-Ver are described. An item means data to be transmitted, in this embodiment, a CAS program.

  Download priority (download_priority) is described in the first byte of the private data area (private_data_byte). In the download priority (download_priority), a value indicating which of broadcast and communication is given priority as a download path is stored. In the following description, download priority (download_priority) may be referred to as a “priority flag”.

(MH-Network Download Content Descriptor Data Structure)
Next, the data structure of the MH-network download content descriptor will be described. FIG. 9 is a diagram illustrating an example of the MH-network download content descriptor. The MH-network download content descriptor includes a compatibility flag (compatibility_flag), a compatibility descriptor (compatibilityDescriptor ()), a session protocol number (session_protocol_number), a reconnection count (retry), an address type (address) type, and an address type. (Address_type) and port number (port_number).
In the compatibility flag (compatibility_flag), a value (1) indicating that there is a compatibility descriptor (compatibilityDescriptor ()) is set as in the example shown in FIG. The compatibility descriptor (compatibilityDescriptor ()) includes the same content as the above-described compatibility descriptor (FIG. 6).

  The session protocol number (session_protocol_number) is a number indicating a protocol (for example, TCP: Transmission Control Protocol) used for network download, that is, download via the communication transmission path 22. The address type (address_type) is a number indicating the type of address indicating the location of the transmission source communication server. In the example shown in FIG. 9, any of IPv4, IPv6, and URL (Uniform Resource Locator) can be specified as the address type. The address indicates the location of the transmission source communication server (for example, the server device 21), and is an address represented by the type specified by the address type (address_type). The port number (port_number) indicates the port number of the communication server.

(Server device processing)
Next, processing performed by the server device 21 (FIG. 1) will be described.
The server device 21 acquires the same distribution data as the distribution data generated by the program acquisition unit 111 of the transmission device 11, and stores the acquired distribution data in a storage unit (not shown) included in the own device. Accordingly, the server device 21 accumulates distribution data storing the latest version of the CAS program at that time. In the example described above, the distribution data includes CAS-ID and CAS-Ver of the CAS program. The server device 21 may acquire distribution data of the software from the transmission device 11 or may acquire the distribution data independently of the transmission device 11.

  The server device 21 may receive a request signal from the receiving device 41 via the communication transmission path 22. The request signal is a signal for requesting distribution data related to the software identified by the designated software identification. The distribution data distribution unit 212 reads distribution data including the same software identification as the software identification specified by the distribution request signal from the storage unit, and transmits the read distribution data to the receiving device 41 via the communication transmission path 22. .

(Receiver configuration)
Next, the configuration of the receiving device 41 according to this embodiment will be described.
FIG. 10 is a block diagram illustrating a configuration of the receiving device 41 according to the present embodiment. The receiving device 41 includes a tuner 411, a demodulation unit 412, a separation unit 413, an audio decoding unit 414, a loudspeaker 415, a video decoding unit 416, a screen synthesis unit 417, a display unit 418, a communication unit 421, a storage unit 422, and an operation input unit. 423 and a control unit 431.

The tuner 411 detects an IF frequency band component (IF frequency band component) corresponding to the physical channel specified by the channel selection signal input from the control unit 431 for the IF signal received from the reception processing facility 31.
The tuner 411 converts the IF frequency band component into multiplexed data that is a baseband signal at the IF center frequency corresponding to the physical channel, and outputs the converted multiplexed data to the demodulation unit 412. Further, the tuner 411 outputs signal strength information indicating the electric field strength to the control unit 431 as the signal strength of the IF frequency band component.

  The demodulation unit 412 demodulates the multiplexed data (modulated) input from the tuner 411 using a demodulation method corresponding to the modulation method used by the modulation unit 116 of the transmission device 11. The demodulator 412 performs predetermined post-processing on the data obtained by the demodulation, and reproduces the demodulated multiplexed data. For example, the demodulator 412 performs deinterleave processing and error correction processing (for example, LDPC decoding and BCH decoding) on the data obtained by demodulation. The demodulator 412 determines whether or not the demodulation is successful by a parity check in an error correction process executed in each decoding. When demodulation is successful, the demodulation unit 412 outputs the reproduced multiplexed data to the separation unit 413 and the control unit 431. Further, the demodulation unit 412 outputs a demodulation state signal indicating whether or not the demodulation is successful to the control unit 431. In the following description, the processing from the received IF signal until the multiplexed data is reproduced may be referred to as front-end processing.

The separation unit 413 separates the multiplexed data input from the demodulation unit 412 into distribution data, program data, notification information, and control information. The separation unit 413 outputs distribution data, notification information, and control information to the control unit 431. Further, the separation unit 413 decrypts the program data (encrypted) and extracts audio data and video data from the decrypted program data. The separation unit 413 performs decoding as the execution of the CAS program activated by the program activation unit 440 (described later) of the control unit 431. Here, the execution of the program means performing a process indicated by an instruction described in the program. As the CAS program to be activated, the CAS program of the latest version specified by the CAS-ID corresponding to the physical channel indicated by the channel signal input from the control unit 431 and already acquired by the receiving device 41 is designated. Can be done.
The separation unit 413 outputs the extracted audio data to the audio decoding unit 414 and outputs the extracted video data to the video decoding unit 416.

The audio decoding unit 414 receives audio data from the separation unit 413. The input audio data is data encoded by a predetermined audio encoding method (for example, MPEG-4 audio). The audio decoding unit 414 decodes audio data using a decoding method corresponding to the encoding method used for encoding, and generates decoded audio data. The decoded audio data is data indicating the audio level at each time. The voice decoding unit 414 outputs the decoded voice data to the loudspeaker 415.
The loudspeaker 415 reproduces voice based on the voice data input from the voice decoder 414. The loudspeaker 415 includes a speaker, for example.

  The video decoding unit 416 receives video data from the separation unit 413. The input video data is data encoded by a predetermined video encoding method. The video decoding unit 416 decodes the video data by a decoding method corresponding to the encoding method (for example, HEVC: High Efficiency Video Coding) used for encoding, and generates decoded video data. The decoded video data is data indicating signal values forming a video (frame image) at each time. The video decoding unit 416 outputs the decoded video data to the screen synthesis unit 417.

The screen combining unit 417 combines the video indicated by the video data input from the video decoding unit 416 and the screen indicated by the screen data input from the control unit 431. The screen synthesis unit 417 outputs display data indicating the synthesized video obtained by synthesis to the display unit 418.
The display unit 418 reproduces the synthesized video indicated by the display data input from the screen synthesis unit 417. The display unit 418 includes a display, for example.

The communication unit 421 transmits and receives various data to and from the server device 21 via the communication transmission path 22. The communication unit 421 is a communication interface, for example.
The storage unit 422 stores various data. The storage unit 422 includes a storage medium, for example, an HDD (Hard-disk Drive), a flash memory, a ROM (Read-only Memory), a RAM (Random Access Memory), or a combination thereof.

  The operation input unit 423 acquires an operation signal in accordance with a user operation input, and outputs the acquired operation signal to the control unit 431. The operation input unit 423 may include a dedicated member such as a switch or a knob as a member for receiving an operation input, or may include a general-purpose member such as a touch sensor. Good. Further, the operation input unit 423 may include an input / output interface that outputs an operation signal received from a remote controller, a mobile phone, or another electronic device to the control unit 431.

  The control unit 431 controls various operations of the receiving device 41. For example, the control unit 431 determines the state of the IF signal input to the receiving device 41 as the received signal received for each physical channel, and determines the decoding state of the CAS program carried by the IF signal. Then, the control unit 431 determines the reception state based on the state of the IF signal between the physical channels and the decoding state of the CAS program. The control unit 431 causes the display unit 418 to display a message screen as notification information regarding the determined reception state.

(Configuration of control unit)
Next, the configuration of the control unit 431 according to the present embodiment will be described.
FIG. 11 is a block diagram illustrating a configuration of the control unit 431 according to the present embodiment. The control unit 431 includes a channel setting unit 432, a control information analysis unit 433, a signal state determination unit 434, a notification information analysis unit 435, a program acquisition unit 436, a program decoding unit 437, a program determination unit 438, a reception state determination unit 439, and a program An activation unit 440 is provided.

The channel setting unit 432 selects one physical channel from a plurality of physical channels within a predetermined search range, and generates a channel selection signal indicating the selected physical channel. The channel setting unit 432 outputs the generated channel selection signal to the tuner 411. Thereby, a physical channel to be received by the tuner 411, that is, an IF frequency band is set.
When the reception state determination unit 439 starts determining the reception state, the channel setting unit 432 receives a determination start signal from the reception state determination unit 439. At this time, the channel setting unit 432 selects an initial value of a predetermined physical channel. The initial value is, for example, a physical channel corresponding to the lowest IF center frequency among physical channels in the search range. After the decoding completion signal is input from the program determination unit 438, the physical channel corresponding to the IF center frequency higher than the physical channel selected at that time is updated to an adjacent physical channel. As a result, the IF frequency band received by the tuner 411 is sequentially changed to a higher frequency band. After all the physical channels in the predetermined search range are selected, the channel setting unit 432 stops the selection of the physical channel and causes the tuner 411 to stop receiving the IF signal.
When displaying the program content, a channel selection signal indicated by the physical channel specified by the operation signal input from the operation input unit 423 is generated, and the generated channel selection signal is output to the tuner 411.

  The control information analysis unit 433 uses the control information input from the demultiplexing unit 413 as network information related to distribution of distribution data, from each frequency region and polarization state of each TLV stream. Read characteristics. Here, the control information analysis unit 433 reads the center frequency of the downlink transmission channel from the frequency region of the TLV stream related to the distribution data, and codes the polarization characteristics described in the polarization region. read. The control information analysis unit 433 identifies a physical channel corresponding to the read center frequency and polarization characteristic, and outputs a reception channel signal indicating the identified physical channel to the signal state determination unit 434.

  Based on the signal intensity information input from the tuner 411 and the demodulated state signal input from the demodulator 412, the signal state determination unit 434 determines the IF frequency band component state related to the physical channel indicated by the control information analyzer 433 as IF. It is determined as the signal status. Note that the signal state determination unit 434 may specify the physical channel indicated by the channel signal acquired from the channel setting unit 432 as the physical channel to be determined for the IF reception state.

  The signal state determination unit 434 determines that the signal strength is sufficient when the signal strength indicated by the signal strength information is higher than a predetermined signal strength threshold, and determines that the signal strength is weak when the signal strength is lower than the threshold. . The signal state determination unit 434 determines whether or not the index of the IF signal quality indicating the multiplexed data (IF signal quality) indicates an IF signal quality higher than a predetermined IF signal quality index threshold. The signal state determination unit 434 uses, for example, any one of CN (Carrier-to-Noise) ratio, BER (Bit Error Rate), or any combination thereof as an index of IF signal quality. The signal state determination unit 434 determines whether or not the CN ratio is higher than a predetermined CN ratio threshold (for example, 18 dB). The BER and CN ratio can be acquired by front-end channel selection processing.

The signal state determination unit 434 determines whether the BER is lower than a predetermined BER threshold (for example, 2 × 10 ⁻⁴ ). The signal state determination unit 434 indicates that the demodulation state signal has been successfully demodulated, and that the CN ratio is higher than a predetermined CN ratio threshold), and that the BER is lower than the predetermined BER ratio threshold. It is determined whether one or both of the conditions are satisfied. The signal state determination unit 434 determines that the IF signal quality is good when it is satisfied, and determines that the IF signal quality is poor when it is not satisfied. The signal state determination unit 434 outputs signal state information indicating the IF signal strength and IF signal quality determined as the state of the IF signal to the reception state determination unit 439.

  The notification information analysis unit 435 extracts the start time (start_time) and the distribution duration (duration) from the notification information input from the separation unit 413, and specifies the distribution time. The notification information analysis unit 435 extracts the CAS-ID and CAS-Ver from the notification information, and specifies the CAS program to be received. The notification information analysis unit 435 extracts a priority flag (download_priority) from the notification information. The notification information analysis unit 435 extracts the address of the server device 21 that is the transmission source by communication from the notification information. The notification information analysis unit 435 outputs the extracted start time (start_time), distribution duration (duration), CAS-ID, CAS-Ver, and address to the program acquisition unit 436.

  The program acquisition unit 436 determines a reception route based on the notification information analyzed by the notification information analysis unit 435. The program acquisition unit 436 determines a reception path for downloading software based on the priority flag (download_priority) input from the notification information analysis unit 435. For example, when the value set in the priority flag (download_priority) is 0x01 or 0x02, the program acquisition unit 436 determines that the download is first performed by broadcasting, and determines the reception path as communication when the download fails. When the value set in the priority flag (download_priority) is 0x03, the program acquisition unit 436 determines that the download is first performed by communication, and determines the reception route as broadcast when the download fails. In addition, when the reception request signal indicating reception by communication is input from the reception state determination unit 439, the program acquisition unit 436 determines the reception path as communication.

  The program acquisition unit 436 inputs distribution data from the separation unit 413 at the distribution time specified by the start time (start_time) and distribution continuation time (duration) input from the notification information analysis unit 435 when the reception route is determined to be broadcast. Is done. In the distribution data, a CAS program specified by CAS-ID and CAS-Ver is stored. On the other hand, the program acquisition unit 436 generates a request signal indicating a request for the CAS program specified by the input CAS-ID and CAS-Ver when determining the reception path as communication. The program acquisition unit 436 transmits the generated request signal to the server device 21 specified by the address input from the notification information analysis unit 435 via the communication unit 421. As a response, the program acquisition unit 436 receives distribution data from the server device 21 via the communication unit 421. The program acquisition unit 436 extracts DAM and individual MPUs that form the acquired distribution data. The program acquisition unit 436 reconstructs the encrypted CAS program and security information by referring to the configuration information stored in the DAM and sequentially connecting the divided data stored in each MPU in ascending order of the MPU sequence number. To do. The program acquisition unit 436 outputs the reconfigured CAS program and security information to the program decryption unit 437.

  The program decryption unit 437 decrypts the input CAS program based on the security information input from the program acquisition unit 436. The program decryption unit 437 decrypts the encrypted CAS program by performing decryption processing described later, and stores the encrypted CAS program, the CAS program obtained by decryption, CAS-ID, CAS-Ver, and the signature value. It outputs to the program determination part 438.

  The program determination unit 438 receives the encrypted CAS program, the decrypted CAS program, CAS-ID, CAS-Ver, and signature value from the program decryption unit 437. The program determination unit 438 reads the root public key certificate RPKC stored in advance in the storage unit 422, and decrypts the signature value with the public key Kpp included in the root public key certificate RPKC. The program determination unit 438 calculates a hash value CAS-H by hashing the encrypted CAS program using a predetermined hash function. The hash function is, for example, SHA-256 (Secure Hash Algorithm 256-bit). When the decrypted signature value matches the hash value CAS-H, it is determined that the CAS program has been successfully decrypted. When the decrypted signature value does not match, it is determined that the CAS program has failed to be decrypted. The program determination unit 438 outputs, to the reception state determination unit 439, program decoding state information indicating the success or failure of decoding as the decoding state of the CAS program for the physical channel.

  Further, the program determination unit 438 stores the CAS program that has been successfully decoded in the storage unit 422 in association with the physical channel, CAS-ID, and CAS-Ver. The program determination unit 438 further stores the CAS program when the CAS-ID and CAS-Ver extracted from the notification information match the input CAS-ID and CAS-Ver, respectively, and stores the program decoding state information. It may be output.

  The reception state determination unit 439 receives the signal state information from the signal state determination unit 434 and the program decoding state indicated by the program decoding state information from the program determination unit 438 for each physical channel. The reception state determination unit 439 determines the broadcast reception state between physical channels based on the state of the IF signal indicated by the signal state information for each physical channel and the program decoding state indicated by the program decoding state information. An example of determining the reception state and an example of the message will be described later.

  The program activation unit 440 identifies the CAS program to be activated by extracting the CAS-ID and CAS-Ver described in the MH-CA activation descriptor acquired from the separation unit 413. The MH-CA activation descriptor is described in a descriptor area of a CA table (CAT: Conditional Access Table) that is separated from multiplexed data by the separation unit 413. The program activation unit 440 reads the specified CAS program from the storage unit 422, activates the read CAS program, and starts its execution. Further, the program activation unit 440 belongs to the system specified by the CAS-ID corresponding to the received channel among the CAS programs stored in the storage unit 422 at that time, and indicates the latest version of the CAS program. -The Ver CAS program may be started. In the initial operation, that is, when no CAS program is received via the broadcast transmission path 12 or the communication transmission path 22, the program activation unit 440 activates the CAS program stored in the storage unit 422 in advance. .

(Decryption process)
Next, the decoding process performed by the program decoding unit 437 will be described.
The program decryption unit 437 extracts the individual information (DMM) from the security information, and the identifier of the receiving device 41 included in the non-encrypted area of the extracted individual information (DMM) is stored in the storage unit 422 in advance. It is determined whether or not the identifier matches. The identifier of the receiving device 41 is information for identifying each receiving device 41, for example, a member ID. When determining that they match, the program decryption unit 437 reads the CAS infrastructure key Kb stored in advance in the storage unit 422 from the storage unit 422. The CAS infrastructure key Kb is a decryption key that can be acquired by a user of the receiving apparatus 41 and a broadcaster by a regular contract. The program decryption unit 437 decrypts the encrypted area of the individual information (DMM) using the read CAS infrastructure key Kb, and extracts the download key Kdl.

Further, the program decryption unit 437 extracts the root public key certificate RPKC from the individual information (DMM), and stores the extracted root public key certificate RPKC in the storage unit 422.
The program decryption unit 437 decrypts the common information (DCM) from the security information input from the program acquisition unit 436 using the extracted download key Kdl, and reconstructs the transmission path protection key Kt used for the encryption of the CAS program. To do. In addition, the program decryption unit 437 reads the CAS-ID, CAS-Ver, and signature value from the compatibility descriptor (compatibleDescriptor ()) described in the common information (DCM). The signature value is data obtained by encrypting the encrypted CAS program using the above-described public key Kpp with respect to the hash value calculated using the above-described hash function.

Further, the program decryption unit 437 reads the master secret key Kms stored in advance in the storage unit 422. The master secret key Kms is the same decryption key (common key) as the encryption key used for encryption of the CAS program provided to the transmission device 11 or the server device 21. The master secret key Kms is also a decryption key that can be acquired by a user of the receiving apparatus 41 and a normal contract between the broadcaster and the user.
The program decryption unit 437 decrypts the CAS program encrypted using the transmission path protection key Kt, further decrypts it using the master secret key Kms, and reconfigures the CAS program.
The program decryption unit 437 outputs the CAS program, CAS-ID, CAS-Ver, and signature value obtained by decryption to the program determination unit 438.

(Reception processing)
Next, the reception process according to the present embodiment will be described.
FIG. 12 is a flowchart showing a reception process according to the present embodiment.
Each unit of the receiving device 41 repeats the processes of steps S101 to S109 within the search range of a predetermined channel. Then, it progresses to step S110.

(Step S101) The channel setting unit 432 updates the physical channel of the IF signal received by the tuner 411 to an adjacent physical channel. However, in the first loop, the channel setting unit 432 sets a predetermined initial value as a physical channel. Thereafter, the process proceeds to step S102.
(Step S102) The demodulation unit 412 demodulates the IF signal received by the tuner 411, and performs the above-described post-processing on the multiplexed data obtained by the demodulation (front-end processing). Thereafter, the process proceeds to step S103.

(Step S103) The signal state determination unit 434 determines whether or not the demodulation of the IF signal by the demodulation unit 412 is successful. When it determines with success (step S103 YES), it progresses to step S104. When it determines with failure (step S103 NO), it progresses to step S108.
(Step S104) The signal state determination unit 434 acquires an index value of either or both of signal strength and signal quality as the state of the IF signal of the received IF signal. Thereafter, the process proceeds to step S105.
(Step S105) The signal state determination unit 434 determines whether or not the acquired index value indicates a signal strength or signal quality that is higher than a predetermined index value threshold. When it is determined that higher signal strength or signal quality is indicated (YES in step S105), the signal state determination unit 434 determines that the signal state is good and proceeds to step S106. When it is determined that the higher signal strength or signal quality is not indicated (NO in step S105), the process proceeds to step S108.

(Step S106) The program acquisition unit 436 acquires distribution data storing the CAS program from the multiplexed data demodulated by the separation unit 413. The program decryption unit 437 decrypts the CAS program based on the security information stored in the distribution data. Thereafter, the process proceeds to step S107.
(Step S107) The program determination unit 438 determines whether the CAS program has been successfully decoded. When determining that the decoding is successful (step S107 YES), the program determination unit 438 notifies the reception state determination unit 439 of the program decoding state information indicating the success of the decoding, and returns to step S101. When it is determined that decoding has failed (NO in step S107), the process proceeds to step S109.

(Step S108) The signal state determination unit 434 determines that the IF signal state is inferior (reception failure), notifies the reception state determination unit 439 of signal state information indicating that the IF signal state is inferior, and proceeds to step S106. move on.
(Step S109) The program determination unit 438 notifies the reception state determination unit 439 of program decoding state information indicating failure of decoding, and returns to step S101.

(Step S110) The reception state determination unit 439 determines a broadcast reception state based on signal state information between physical channels and program decoding state information. The reception state determination unit 439 causes the display unit 418 to display a message screen corresponding to the determined reception state. Then, the process shown in FIG.

(Example of reception status list)
Next, an example of the reception status list will be described. The reception state list is a list in which signal state information and program decoding state information are associated with each other and arranged in ascending or descending order of physical channels. The reception state determination unit 439 generates a reception state list based on the signal state information and the program decoding state information acquired for each physical channel, and outputs the generated reception state list to the screen synthesis unit 417, thereby displaying the display unit 418. May be displayed.

FIG. 13 is a diagram illustrating an example of a reception state list according to the present embodiment.
In the example shown in FIG. 13, a set of signal strength, signal quality, and program decoding state for each physical channel in the search range is represented in each row. Each set is arranged in ascending order of physical channels, that is, corresponding IF center frequencies, from the upper stage toward the lower stage. Each of the 12 physical channels from BS1, BS3,... BS23 is a channel group corresponding to a downlink transmission channel transmitted from the BS with right-handed polarization (BS right-handed). 12 channels from ND2, ND4,... ND24 are all channel groups corresponding to downlink transmission channels transmitted from CS with right-handed polarization (CS left-handed). Each of the 12 physical channels from BS2, BS4,..., BS24 is a channel group corresponding to a downlink transmission channel transmitted from the BS with left-handed polarization (BS left-handed). The 12 channels from ND1, ND3,... ND23 are all channel groups corresponding to the downlink transmission channel transmitted from CS with left-handed polarization (CS left-handed).

  The signal strength is represented by a bar graph. The higher the signal strength, the longer the bar graph. The signal quality is a score obtained by combining the index values (for example, CN ratio, BER, etc.). The signal quality is represented by any integer value from 0 to 10. The signal strength tends to become weaker as the IF center frequency increases. For example, the length of the bar graph indicating the signal strength of BS2 is approximately half the length of the bar graph indicating the signal strength of BS1. At frequencies higher than BS24, the signal strength approximates to zero. The signal quality tends to deteriorate as the IF center frequency increases. For example, between BS1 to ND4, the signal quality value is 8, whereas the signal quality value of BS2 is 5, and the signal quality value is 0 at the IF center frequency of BS6 or higher. From these results, it is determined that the signal state is good in the physical channel of ND24 or lower, and the signal state is inferior in the physical channel of BS2 or higher.

  As the program decryption state, success of decryption is represented by-, and failure of decryption is represented by x. The physical channel that is blank indicates that the CAS program is not decoded because the signal state is inferior. For example, the CAS program is decoded between BS1 and BS2, the decoding is successful between BS1 to BS15 and BS19 to BS2, and the decoding of BS17 is failed. At the IF center frequency of BS4 or higher, neither the-mark nor the X mark is displayed. This indicates that the CAS program was not decoded at the IF center frequency of BS4 or higher.

(Display example)
Next, a display example relating to reception processing will be described.
FIG. 14 is a diagram illustrating a display example according to the reception process according to the present embodiment.
FIG. 14A shows an example of a connection confirmation screen. The connection confirmation screen is a screen that the control unit 431 displays on the display unit 418 during execution of the front end processing by the demodulation unit 412 or the processing of determining the state of the IF signal in the signal state determination unit 434. The connection confirmation screen is configured to include a message Ms11 indicating “confirming connection” and a progress bar Pg11 indicating the progress status of the ongoing process. When displaying the connection confirmation screen, the control unit 431 reads the connection confirmation screen data stored in the storage unit 422 in advance, and outputs the read connection confirmation screen data to the screen composition unit 417.

FIG. 14B shows an example of a version confirmation screen. The version confirmation screen is a screen that the control unit 431 displays on the display unit 418 during execution of the CAS program decoding process in the program decoding unit 437 or the determination of whether or not the CAS program can be decoded in the program determination unit 438. The version confirmation screen is configured to include a message Ms12 indicating “CAS program version confirmation in progress” and a progress bar Pg12.
When displaying the version confirmation screen, the control unit 431 reads the version confirmation screen data stored in advance in the storage unit 422, and outputs the read version confirmation screen data to the screen composition unit 417.

(Determination of reception status)
Next, reception state determination processing by the reception state determination unit 439 will be described.
FIG. 15 is a diagram for explaining reception state determination processing according to the present embodiment.
In the example shown in FIG. 15, the IF center frequency is shown in the horizontal direction. The trapezoids including the characters BS right-handed, CS right-handed, BS left-handed, and CS left-handed have a frequency band of each channel group of 1.0-1.5 GHz, 1.6-2.1 GHz, 2.2-2.7 GHz. 2.8-3.3 GHz. Each channel group includes an IF frequency band corresponding to each of the 12 physical channels. The solid arrows in the uppermost line in FIG. 15 indicate that the CAS program received via the physical channel belonging to the BS clockwise and CS clockwise can be decoded. The dashed double-pointed arrow on the left side of the second stage indicates that the state of the IF signal of the physical channel belonging to the BS clockwise and CS clockwise is good (good reception). A good IF signal state means that no bit error occurs (or correction is possible even if a bit error occurs), the signal strength is sufficient, and the signal quality is good. The dashed double-pointed arrow on the right side of the second stage indicates that the IF signal state of the physical channel belonging to the BS left-handed or CS left-handed channel group is inferior (reception failure). The inferior state of the IF signal means either a bit error that cannot be corrected, a weak signal strength, a poor signal quality, or a combination thereof. As a cause of such a reception state, it is presumed that the reception processing facility 31 does not have a left-handed polarized wave component receiving means (for example, an antenna or a converter).

  Therefore, the reception state determination unit 439 determines whether the state of the IF signal of the physical channel related to a certain polarization component (left-handed polarization component in the example of FIG. 15) is another polarization as the reception state of the broadcast between physical channels. It is determined whether or not the state (state C1) is inferior to the state of the IF signal of the channel related to the component (in the example of FIG. 15, right-handed polarization component). For example, the reception state determination unit 439 determines that the reception state is the state C1 in the following case. In the following case, it is determined that the state of the IF signal in the channel group related to another polarization component is inferior from the ratio of the number of physical channels determined to be inferior in the channel group related to a certain polarization component. This is a case where the difference from the ratio of the number of physical channels is greater than a predetermined difference threshold value 1. When determining the state C1, the reception state determination unit 439 reads the message screen data C1 associated with the state C1 from the message screen data stored in advance in the storage unit 422, and uses the read message screen data C1. The data is output to the screen composition unit 417. Accordingly, the reception state determination unit 439 can display the message screen C1 indicated by the message screen data C1 on the display unit 418 as notification information.

  The double arrows on the left side of the fourth stage in FIG. 15 indicate that the state of the IF signal of the physical channel whose IF intermediate frequency is lower than 2.6 GHz is good (good reception). On the other hand, the double arrows on the right side of the same stage indicate that the state of the IF signal of the physical channel whose IF intermediate frequency is higher than 2.6 GHz is inferior (reception failure). As a cause of such a reception state, a device that can process a high-frequency IF signal (for example, a booster) is not connected, or wiring that cannot transmit an IF signal while maintaining sufficient signal strength is used. Is inferred. One reason why sufficient signal intensity cannot be maintained is that the higher the IF intermediate frequency, the higher the impedance of the wiring from the reception processing facility 31 to the reception device 41.

  Therefore, the reception state determination unit 439 sets the IF signal state of the physical channel of the IF intermediate frequency higher than a certain frequency as the reception state of the broadcast between the physical channels and the IF of the physical channel of the IF intermediate frequency lower than the certain frequency. It is determined whether the state is inferior to the state of the signal (state C2). For example, the reception state determination unit 439 determines that the reception state is the state C2 by performing the following processes (i) and (ii). (I) A physical channel that provides a reference frequency with the largest difference in the ratio of the number of predetermined physical channels is searched from the physical channels within the search range. As a difference in the ratio of the predetermined number of physical channels, from the ratio of the number of physical channels determined to be inferior in the state of the IF signal in the physical channel related to the IF intermediate frequency higher than the reference frequency, to the IF intermediate frequency lower than the reference frequency. A difference from the ratio of the number of physical channels determined to be inferior in the state of the IF signal in the physical channel is calculated. (Ii) When the difference in the ratio of the number of physical channels calculated for the searched physical channels is larger than a predetermined difference threshold, it is determined that the broadcast reception state between the physical channels is the state C2.

  In the example illustrated in FIG. 15, it is determined that the state of the IF signal is inferior to that of the physical channel having the IF intermediate frequency lower than that of the physical channel having the IF intermediate frequency higher than 2.6 GHz. When determining to be the state C2, the reception state determination unit 439 reads the message screen data C2 associated with the state C2, and outputs the read message screen data C2 to the screen composition unit 417. Thereby, the reception state determination unit 439 can display the message screen C2 indicated by the message screen data C2 on the display unit 418 as notification information.

  The three double arrows in the third row in FIG. 15 indicate the physical channel of the IF signal that carries the decoded CAS program to the physical channel whose IF intermediate frequency is lower than 2.6 GHz, and the CAS program that cannot be decoded. It shows that the physical channel of the IF signal carried is included. In such a reception state, there is no particular problem in signal reception, demodulation, and decoding processing itself, and it is assumed that decoding fails due to individual CAS programs.

  Therefore, the reception status determination unit 439 sets the physical channel of the IF signal carrying the CAS program that has been successfully decoded to the physical channel in which the IF signal status is better than the predetermined status, as the broadcast reception status between the physical channels. It is determined whether or not the state (state C3) includes both physical channels of the IF signal carrying the CAS program that has failed in decoding. The state C3 indicates that there is a physical channel carrying a CAS program that cannot be decoded only in a part of the physical channel in which the state of the IF signal is good. When determining the state C3, the reception state determination unit 439 reads the message screen data C3 associated with the state C3, and outputs the read message screen data C3 to the screen composition unit 417. Thereby, the reception state determination unit 439 can display the message screen C3 indicated by the message screen data C3 on the display unit 418 as notification information. Note that the reception state determination unit 439 may determine whether or not it corresponds to the state C3 regardless of whether or not it corresponds to the state C1 or C2. In addition, the reception state determination unit 439 can exclude and receive a physical channel for which the CAS program cannot be received because it is out of the delivery time notified by the notification information from the determination target of whether or not the state is C3. Only physical channels that have been determined may be determined.

(Example of message screen display)
Next, an example of a message screen according to the present embodiment will be described.
FIG. 16 is a diagram illustrating an example of a message screen according to the present embodiment.
FIG. 16A shows a display example of the message screen C1.
The message screen C1 is configured to include a message Ms21 and a delete button indicating an x mark surrounded by a rectangle. The message Ms21 is configured to include a message “There is a possibility that the antenna may not be compatible” and a message indicating “Please check” as a countermeasure as a cause that may cause the state C1. . When the operation signal indicating the delete button or the position of the delete button is input by the operation signal, the reception state determination unit 439 stops the output of the message screen data C1 and deletes the display of the message screen C1. In the following description, input of an operation signal indicating a certain screen element or its position in accordance with a user operation is referred to as “pressing” the screen element.

FIG. 16B shows a display example of the message screen C2.
The message screen C2 includes a message Ms22 and a delete button. The message Ms22 includes a message “Please check the equipment and wiring between the antenna and the receiver” as a measure for solving the cause that may cause the state C2.

FIG. 16C shows a display example of the message screen C3.
The message screen C3 includes a message Ms23, a delete button, and a confirmation button. In the example shown in FIG. 16C, the delete button is a button to which the letters “after” are enclosed in a rectangle. On the other hand, the confirmation button is a button with a character “YES” surrounded by a rectangle. The message Ms23 includes a message “There is a problem with the CAS program” as a cause that may cause the state C3, and a message “Do you want to download the latest version?” As a countermeasure.

  When the confirmation button “Yes” displayed on the message screen C3 is pressed, the reception state determination unit 439 specifies the CAS-ID and CAS-Ver of the CAS program that has failed to be decrypted, and communicates with the CAS program. A reception request signal indicating reception of the message is output to the program acquisition unit 436. Accordingly, the reception state determination unit 439 can cause the program acquisition unit 436 to acquire the CAS program by communication.

  Also, when the reception status list (FIG. 13) is displayed on the display unit 418, when any of the X marks displayed in the program decoding status column is pressed, the reception status determination unit 439 Identify physical channels. Then, the reception state determination unit 439 generates error screen data including failure factor information indicating the cause of failure of decoding of the CAS program for the specified physical channel, and outputs the generated error screen data to the screen synthesis unit 417. Thereby, the reception state determination unit 439 can display an error screen on the display unit 418. As a premise thereof, the program determination unit 438 further includes failure factor information indicating the detected factor for the physical channel in which the decoding of the CAS program has failed, and outputs the failure factor information to the reception state determination unit 439.

(Error screen)
Next, the error screen will be described.
FIG. 17 is a diagram illustrating an example of an error screen according to the present embodiment.
The example shown in FIG. 17 is an error screen E0 that is displayed by pressing the x mark (FIG. 13) in the program decoding state related to BS17. Causes of failure include (1) inconsistency of CAS program, (2) non-acquisition of security information due to contract not being concluded, and (3) non-acquisition of target program. Regarding (1), the program determination unit 438 can detect that the signature value and the hash value CAS-H do not match (program check). (2) can be detected by the fact that the CAS determination key Kb and the master secret key Kms required for the decryption process by the program determination unit 438 are not stored in the storage unit 422 (contract check). As for (3), the program determination unit 438 stores the CAS program in which the distribution data has not been received and the CAS-ID and CAS-Ver notified by the notification information (MH-SDTT) match. It can be detected that the data is not stored in the unit 422 (download check). The example of the error screen E0 shown in FIG. 17 corresponds to (1) (×), does not correspond to (2) (◯), and does not correspond to (3) (−).

  Further, the reception state determination unit 439 may read error screen data indicating an error screen indicating a factor corresponding to a failure factor of decoding from the storage unit 422, and output the read error screen data to the screen synthesis unit 417. . Thereby, an error screen showing individual factors is displayed on the display unit 418.

FIG. 18 is a diagram illustrating another example of the error screen according to the present embodiment.
FIG. 18A is an example of an error screen E1 displayed when the failure factor is (1) CAS program inconsistency. The error screen E1 includes a message Ms31, a confirmation button, and an erase button. In the example shown in FIGS. 18A and 18C, the delete button is a button to which the characters “after” are enclosed in a rectangle. On the other hand, the confirmation button is a button with a character “YES” surrounded by a rectangle. The message Ms31 includes a message “There is a problem with the CAS program” as a possible failure factor and a message “Do you want to download the latest version?” As a countermeasure.

  FIG. 18B is an example of an error screen E2 displayed when the failure factor is (2) the security information is not acquired due to the contract not being concluded. The error screen E2 includes a message Ms32 and an erase button. In the example shown in FIGS. 18B and 18D, the delete button is a button marked with an X mark surrounded by a square. The message Ms32 includes a message “no contract information” as a possible failure factor and a message “please perform contract procedure” as a countermeasure.

  FIG. 18C is an example of an error screen E3 displayed when the failure factor is (3) the target program has not been acquired. The error screen E3 includes a message Ms33, a confirmation button “Yes”, and an erase button “Later”. The message Ms33 is configured to include a message “CAS program download failure” as a possible failure factor and a message “Do you want to download the latest version?” As a countermeasure. When the confirmation button “Yes” displayed on the error screen E3 is pressed, the reception state determination unit 439 specifies and specifies the CAS-ID and CAS-Ver of the CAS program that has failed to be acquired for the physical channel. A reception request signal for instructing reception of the received CAS program via communication is output to the program acquisition unit 436. Thereby, the reception state determination unit 439 can acquire the CAS program specified by the program acquisition unit 436 by communication.

Note that the reception state determination unit 439 may detect whether or not the communication unit 421 is connected to the communication transmission path 22. When it is determined that it is not connected to the communication transmission path 22, the error screen data indicating that fact is read from the storage unit 422, and the read error screen data is output to the screen composition unit 417, thereby displaying the error screen E 4. It may be displayed on the part 418.
FIG. 18D is an example of the error screen E4. The error screen E4 includes a message Ms34 and a delete button. The message Ms34 is configured to include a message “please check the network connection” as a countermeasure against being not connected to the communication transmission path 22.

As described above, the reception device 41 according to the present embodiment determines the signal state determination unit 434 that determines the state of the IF signal received for each physical channel, and the decoding state of the CAS program carried by the IF signal. The program determination part 438 to perform is provided. In addition, a reception state determination unit 439 that determines the reception state of the broadcast between the physical channels based on the state of the IF signal for each physical channel in the search range and the decoding state of the CAS program is provided.
With this configuration, information transmitted via broadcast waves cannot be acquired because of factors affecting the state of the received IF signal for each physical channel, factors affecting the decoding of the CAS program, and those between physical channels. Can be distinguished from these factors. Therefore, it is possible to efficiently estimate the cause of failure to acquire information transmitted by broadcast waves.

Further, the reception state determination unit 439 determines whether the state of the IF signal of the physical channel related to a certain polarization component is inferior to the state of the IF signal of the physical channel related to another polarization component as the reception state between physical channels. Determine whether or not.
With this configuration, it is possible to estimate whether or not the cause of failure to acquire information transmitted by broadcast waves is a lack of receiving equipment for receiving a certain polarization component.

Also, the reception state determination unit 439 determines whether the state of the IF signal of a channel having a frequency higher than a certain frequency is inferior to the state of the IF signal of a channel having a frequency lower than a certain frequency as the reception state between physical channels. judge.
With this configuration, the reason why the information transmitted by the broadcast wave cannot be acquired is a device or wiring suitable for transmitting an IF signal having a frequency higher than a certain frequency as a device or wiring connected to the receiving device 41 from the receiving facility. It can be estimated whether it is being used.

Also, the reception state determination unit 439 receives the physical channel of the IF signal carrying the CAS program that has been decoded into the physical channel in which the state of the IF signal is better than the predetermined state as the reception state between the physical channels and the CAS that cannot be decoded. It is determined whether or not the physical channel of the IF signal carrying the program is included.
With this configuration, it is possible to estimate whether or not the cause of failure to acquire information transmitted by broadcast waves is a factor of each CAS program.

In addition, the reception state determination unit 439 outputs notification information regarding the reception state between the determined physical channels to the screen synthesis unit 417.
With this configuration, for example, the user is notified of the cause of failure to acquire information transmitted by broadcast waves and the countermeasures as notification information. Therefore, the user is prompted to take an action to acquire information transmitted by broadcast waves.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope indicated in the claims, and the technical configurations disclosed in different embodiments are appropriately combined. The obtained embodiment is also included in the technical scope of the present invention.
Each component of the present invention can be arbitrarily selected, and an invention having a selected configuration is also included in the present invention.

For example, the transmission device 11 and the server device 21 may be configured as a single transmission device. Any of the loudspeaker 415, the display unit 418, and the operation input unit 423 of the reception device 41 or any combination thereof may be separate from the other parts of the reception device 41. The notification information may be notified by voice from the loudspeaker 415.
Moreover, the display forms of the various screens described above and the displayed words can be arbitrarily changed.

  In the above-described embodiment, the transmission apparatus 11 transmits mainly various types of data to the reception processing facility 31 via the broadcast transmission path 12. However, the example mainly uses right-handed circular polarization and left-handed circular polarization. The polarization characteristics of the plurality of transmission channels are different from each other, and preferably orthogonal polarizations may be used. For example, horizontal polarization and vertical polarization may be used.

  In the above-described embodiment, the case where the media transport system according to MMT (MPEG Media Transport) defined by MPEG-H is used as the transmission system for transmitting various data is exemplified. A method, for example, a method defined by MPEG-2 Systems may be used. In addition, a data format, an encryption method, and an encoding method related to transmission may be a format or a method defined by the transmission method. For example, distribution data indicating software may be transmitted as a DII (Download Info Indication) message or a DDB (Download Data Block) message instead of the DAM and MPU.

  Further, a part of the transmission device 11 and a part of the reception device 41 in the above-described embodiment may be realized by a computer. In that case, the program for realizing the control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. Here, the “computer system” is a computer system built in the recognition data transmission apparatus, and includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” is a medium that dynamically holds a program for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, In this case, a volatile memory inside a computer system that serves as a server or a client may be included that holds a program for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

In addition, this invention can be implemented also in the following aspect.
(1) A signal state determination unit that determines a state of a received signal received for each channel, a program determination unit that determines a decoding state of a program carried by the received signal, the state of the received signal for each channel, and the A reception apparatus comprising: a reception state determination unit that determines a reception state between channels based on a decoding state of a program.

(2) The reception state determination unit determines whether a reception signal state of a channel related to a certain polarization component is inferior to a reception signal state of a channel related to another polarization component as the reception state between the channels. The receiving apparatus of (1) that determines whether or not.

(3) The reception state determination unit determines whether a reception signal state of a channel having a frequency higher than a certain frequency is inferior to a reception signal state of a channel having a frequency lower than the certain frequency as the reception state between the channels. The receiving apparatus of (1) or (2) that determines whether or not.

(4) The reception state determination unit carries, as a reception state between the channels, a channel of a reception signal that has carried a decoded program and a program that cannot be decoded into a channel in which the state of the reception signal is better than a predetermined state. The receiving apparatus according to any one of (1) to (3), which determines whether or not the received signal channel is included.

(5) The reception device according to any one of (1) to (4), wherein the reception state determination unit outputs notification information related to a reception state between the channels.

(6) In the receiving method of the receiving apparatus, a signal state determining process for determining the state of the received signal received for each channel, a program determining process for determining the decoding state of the program carried by the received signal, and for each channel A reception method comprising: a reception state determination step of determining a reception state between channels based on a state of the reception signal and a decoding state of the program.

(7) A signal state determination procedure for determining the state of the received signal received for each channel in the computer of the receiving device, a program determination procedure for determining the decoding state of the program carried by the received signal, and the received signal for each channel And a reception state determination procedure for determining a reception state between channels based on the decoding state of the program.

  DESCRIPTION OF SYMBOLS 1 ... Broadcasting system, 11 ... Transmission apparatus, 111 ... Program acquisition part, 112 ... Program data acquisition part, 113 ... Notification information acquisition part, 114 ... Control information acquisition part, 115 ... Multiplexing part, 116 ... Modulation part, 117 ... Antenna, 12 ... Broadcast transmission path, 13 ... Artificial satellite, 21 ... Server device, 22 ... Communication transmission path, 31 ... Reception processing equipment, 41 ... Reception device, 411 ... Tuner, 412 ... Demodulation unit, 413 ... Separation unit, 414 ... voice decoding unit, 415 ... loudspeaker unit, 416 ... video decoding unit, 417 ... screen synthesis unit, 418 ... display unit, 421 ... communication unit, 422 ... storage unit, 423 ... operation input unit, 431 ... control unit, 432 ... Channel setting unit, 433 ... control information analysis unit, 434 ... signal state determination unit, 435 ... notification information analysis unit, 436 ... program acquisition unit, 437 ... program decoding unit, 438 ... program Grams determination unit, 439 ... reception state determination unit, 440 ... program activation unit

Claims (7)

A signal state determination unit for determining the state of the received signal received for each channel;
A program determination unit that determines a decryption state that is a success or failure of decryption of the conditional access system program carried by the received signal and encrypted ;
Based the state of the received signal of each channel to the decoding state of the conditional access system program, a reception state determining unit determines the reception state of each channel group including a plurality of channels,
Bei to give a,
The reception state determination unit includes both a channel related to a conditional access system program that has been successfully decoded and a conditional access system program that has failed to be decoded in a channel group including a plurality of channels whose reception state is better than a predetermined state. Receiving device for determining whether or not The reception state determining unit, as the reception state of the channel group, a channel included in the channel group, the state of the channel of the received signal according to a certain polarization components, of the channel according to another polarization component received The receiving device according to claim 1, wherein it is determined whether or not the signal is inferior to a signal state. The reception state determining unit, as the reception state of the channel group, the a channel included in the channel group, the state of the received signal of the channel having a frequency higher than a frequency reception channel frequency lower than said certain frequency The receiving apparatus according to claim 1, wherein it is determined whether or not the signal is inferior to a signal state. The receiving apparatus according to any one of claims 1 to 3 , wherein the reception state determination unit outputs notification information regarding a reception state of the channel group . When the channel group consisting of a plurality of channels whose reception status is better than the predetermined status includes both the channel related to the conditional access system program that has been successfully decoded and the conditional access system program that has failed to be decoded, the reception status determination The unit outputs a message screen including a message indicating a problem of the conditional access system program and a confirmation button as the notification information, and when the confirmation button is pressed, the conditional access system program that failed to be decrypted is sent to the program acquisition unit. The receiving device according to claim 4, acquired by communication. In the receiving method of the receiving device,
A signal state determination process for determining the state of the received signal received for each channel;
A program determination process for determining a decryption state that is a success or failure of decryption of the conditional access system program carried by the received signal and encrypted ;
Based the state of the received signal of each channel to the decoding state of the conditional access system program, a reception state determining process determines the reception state of each channel group including a plurality of channels,
I have a,
The reception state determination process includes both a channel related to a conditional access system program that has been successfully decoded and a conditional access system program that has failed to be decoded in a channel group including a plurality of channels whose reception state is better than a predetermined state. Receiving method for determining whether or not In the computer of the receiving device,
Signal status determination procedure for determining the status of the received signal received for each channel,
A program determination procedure for determining a decryption state that is a success or failure of decryption of the conditional access system program carried by the received signal and encrypted ;
Based the state of the received signal of each channel to the decoding state of the conditional access system program, the reception state determining step determines the reception state of each channel group including a plurality of channels,
A receiving program for executing,
The reception state determination procedure includes both a channel related to a conditional access system program that has been successfully decoded and a conditional access system program that has failed to be decoded in a channel group including a plurality of channels whose reception state is better than a predetermined state. Whether or not
Receiving program .

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