JP4508243B2 - Receiving apparatus and receiving method - Google Patents

Description

  The present invention relates to a receiving apparatus and a receiving method for transmitting a plurality of program data using, for example, digital satellite broadcasting.

  Currently, digital satellite broadcasting, which uses a communication satellite to transmit digital data and broadcasts, is becoming widespread. In this digital satellite broadcasting, video and audio signals are compression-coded and digitized by a predetermined method, and the digitized video and audio signals are transmitted to a viewer via a communication satellite. For example, MPEG2 (Moving Picture Experts Group) is used as a compression encoding method for video and audio signals.

  FIG. 10 shows an outline of a typical digital broadcasting system. The program sending side is composed of an uplink station, a program provider, and a management system.

The video / audio data from the program provider 101 is MPEG (Moving) of the uplink station 102.
(Picture Expert Group) 2 is supplied to the multiplexer 103. In the MPEG2 encoder and multiplexer 103, the video / audio data is compressed, and the compressed video / audio data is packed into a packet having a length of 188 bytes. Video / audio data packets corresponding to a plurality of programs are multiplexed to form an MPEG2 transport packet. A transport stream is formed by concatenating transport packets. The number of transport streams corresponds to the number of transponders mounted on the communication satellite.

  MPEG2 transport packets are supplied to the transmission system 104. In the transmission system 104, scramble processing for each packet, error correction encoding for each packet, modulation, and the like are performed, and the modulation output is supplied to the transmission antenna 105. The scramble process is required for realizing conditional access used for controlling whether or not viewing is possible for each viewer. For example, a pay-per-view contract can be made in which only a certain program is watched for a fee. The key for descrambling is supplied from the key management system 106 to the MPEG2 encoder and multiplexer 103, and is inserted into the transport packet as one of the packets, like the video / audio information.

  The program management system 107 performs integrated management of MPEG2 packets. The program management system 107 and the key management system 106 are combined to encrypt the scrambled key. Further, a customer management system 108 is provided to manage items related to the viewing contract. Billing information is transmitted between the viewer's home and the telephone line 109.

  Transmitted from the transmitting antenna 105 and broadcast radio waves are received by the receiving antenna 111 of each home via the communication satellite 110. A receiver 112 is connected to the receiving antenna 111. The receiver 112 includes a tuner that specifies a reception transponder, a demodulation unit, a descrambling unit that unscrambles, a demultiplexer that specifies a packet to be separated, a video decoding unit, an audio decoding unit, and the like. The decoded video / audio signal is supplied to the television receiver 113.

  The key for descrambling is encrypted and transmitted as video and audio as related information. The key for decrypting this encryption is stored in the IC card 114 inserted in the receiver 112. Which program can be unscrambled can be controlled from the transmission side based on the contract information of each receiving system. A receiver having a conditional access function is usually called an IRD (Integrated Receiver / Decoder).

The above-described digital satellite broadcasting system has just started to be put into practical use, and various changes may be made to the program for controlling the current receiver on the receiving side. Therefore, this program is stored as data in a rewritable ROM built in the receiver. As a rewritable ROM, for example, EEPROM (Electrically
Flash ROM such as Erasable Programmable ROM). This change is generally aimed at providing new services and added value to customers. Several measures are possible as countermeasures when such program changes are made.

  For example, the program change can be dealt with by exchanging the program ROM built in the receiver or exchanging the entire receiver. Further, by using an IC card interface provided in the receiver, an IC card storing a new reception program can be distributed to the customer, and a new program can be loaded from the IC card. However, when the number of receivers already installed is large, it is difficult to replace the ROM of the receiver and collect the receiver. Also, the method of distributing the IC card has a problem that not only is the cost burden high, but the IC card has a relatively small memory capacity, so that it is difficult to store the program there.

  As a method for solving such a problem, it has been proposed that the latest program information is transmitted from the transmission side and this program is loaded into the receiver on the reception side. That is, the program data is downloaded by inserting the program data into a data stream transmitted by, for example, the MPEG2 system by satellite broadcasting, and receiving it by a viewer. The downloaded program data is temporarily written, for example, in a RAM built in the receiver, and the program data is transferred from the RAM to the flash ROM, and the program is rewritten.

  Conventionally, one type of software has been applied to all receiving apparatuses. In other words, a necessary one is not selected from a plurality of types of software. Therefore, on the receiver side, it is necessary to determine the type of the host processor (CPU) and OS (Oparation System), the type of interpreter for executing the program, etc., and these are not unified receivers. There was a problem that could not be downloaded.

  For example, in a personal computer, when downloading a program, the operator can check the version of the program and compare it with the version of the same program currently held. Thereby, in a personal computer or the like, it is possible to avoid downloading the same version of the program repeatedly.

  Conventionally, however, downloading by such a satellite broadcast receiver has been performed regardless of the version of the program to be downloaded. Therefore, there is a problem that the same version of the program that has already been downloaded may be redundantly downloaded. Furthermore, there is a problem that the downloaded program may be an older version than the program already possessed.

  Also, in the download by the personal computer, the determination of the version information is left to the operator's hand, so there is a possibility that the download will fail as described above.

  Further, the downloaded program data has a size of, for example, several MBytes. Therefore, downloading takes several minutes to several tens of minutes. Conventionally, the progress of downloading, for example, what percentage of the total size of program data has been downloaded has not been displayed. For this reason, there is a problem in that it is not possible to know when the download is finished, which causes dissatisfaction for the operator who executed the download.

  On the other hand, when a plurality of types of program data are to be transmitted, a method may be considered in which a plurality of transmission paths are used and each is transmitted through a separate path. For example, in the case of this satellite broadcast, a plurality of transponders each assigned with a different carrier frequency are used, whereby a data stream is transmitted to the receiver. Therefore, a transponder can be assigned for each receiver manufacturer and model. However, conventionally, there is no information indicating which program data is transmitted from which transponder. For this reason, there is a problem that the corresponding program data cannot be downloaded on the receiver side.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a receiving apparatus and a receiving method capable of selecting and downloading appropriate data from a plurality of data transmitted by multiplexing.

The present invention, in order to solve the problems described above, a video signal, audio signal and additional data are divided into a predetermined length packets, the packet a plurality of transport stream multi duplex is modulated at different frequencies, Receiving means for receiving the broadcast signal from the transponder, wherein the plurality of modulated transport streams are relayed by a transponder that relays radio waves of a predetermined frequency band;
Demodulation means for demodulating the broadcast signal received by the received signal;
Separating means for restoring a packet from the broadcast signal demodulated by the demodulating means , and separating the video signal, audio signal and additional data from the packet ;
Extraction that extracts the transport stream ID indicating which transponder has been transmitted , the version ID of the update download content, the manufacturer identification information and the model identification information of the receiving device from the additional data separated by the separation means Means,
Based on the transport stream ID extracted by the extraction means to identify the transponders, and controls the receiving means to receive broadcast signals from the identified transponder, by extracting means from the broadcast signal received by the receiving means based on the extracted manufacturer identification information and model identification information download update download content included in the transport stream, compares the version ID of the program data stored version ID, if they match And a control unit that updates program data in the receiving apparatus. Further, the present invention is the reception how to receive such broadcast signal.

  As described above, since the receiver manufacturer identification information for identifying the manufacturer of the receiver and the receiver model identification information for identifying the model for each manufacturer of the receiver are transmitted, the present invention is multiplexed. Appropriate information can be selected and received from a plurality of pieces of information transmitted.

  As described above, according to the present invention, different program data can be transmitted for each receiver manufacturer and model. Therefore, there is an effect that it is possible to download program data for all receivers without unifying the host processor, the OS, and the interpreter on the receiving side.

  In addition, according to the present invention, it is possible to know the version information of the program data transmitted by the version ID, so that there is an effect that it is possible to avoid unnecessary down-loading.

  Furthermore, in this embodiment, there is an effect that the progress of down-loading can be displayed. As a result, there is an effect that it is possible to avoid stressing the user even in the case of a relatively slow down load.

  Furthermore, according to the present invention, even if there are a wide variety of manufacturers and models, there is an effect that program data corresponding to each manufacturer can be transmitted by an arbitrary transponder.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a data transmission system applicable to this embodiment. In this system, video, audio, or other data, which is a bit-serial data stream on the transmission side, is modulated and transmitted by the transmission facility 4 as radio waves in a predetermined frequency band. This radio wave is relayed by the communication satellite 5 and received by the receiver 6.

  On the transmission side, a video signal, an audio signal, and additional data are supplied to the encoder 1. The additional data is, for example, text data or other audio data, and can include binary data such as program code data. In the encoder 1, these supplied signals and data are encoded with high efficiency and encoded.

  In this embodiment, the encoder 1 uses the MPEG2 system for this high-efficiency encoding. That is, the video signal is subjected to motion compensation by DCT (Discrete Cosine Transform) and motion vector calculation, and is encoded by being quantized. In addition, the audio signal is subjected to subband coding using psychoacoustic coding. Note that binary data such as program code data is encoded by a predetermined method as necessary.

  In the encoder 1, the encoded video, audio and additional data are further time-division multiplexed to form a bit-serial data stream. This data stream is supplied to the multiplexing unit 2. In this system, in order to support transmission of a plurality of channels in one frequency band, a plurality of encoders 1, for example, six channels can be provided for each frequency band. Data streams output from the respective encoders 1 are supplied to the multiplexing unit 2.

  In the multiplexing unit 2, these supplied data streams are further multiplexed by, for example, time division multiplexing. In MPEG2, a data stream is divided into units called packets and transmitted. As shown in FIG. 2, one packet includes a header portion of 4 bytes and a payload portion of 184 bytes and has a size of 188 bytes. The divided data stream is stored in the payload portion. The header portion stores information on each packet, information representing a relationship between packets, and the like. This header portion is provided with a PID which is identification information of this packet.

  That is, in the multiplexing unit 2, the supplied data stream is divided every 184 bytes, and a predetermined header information is added to generate a packet, which is multiplexed to be a transport packet. . The same PID is attached to transport packets generated from the same data stream. A series of transport packets in a transmission format is called a transport stream. The transport stream output from the multiplexing unit 2 is supplied to the modulator 3.

The modulator 3 applies QPSK (Quadrature Phase Shift) to the transport packet.
(Keying) Modulation is performed and a modulated signal in a predetermined frequency band is output. The modulated signal output from the modulator 3 is supplied to a transmission facility 4 including a power amplifier, a transmission antenna, and the like.

  Actually, a scramble process for a transport packet, an error correction encoding process using a Reed-Solomon code, an interleaving process corresponding to a burst error, a convolutional encoding process, and the like are performed.

  Transmission can be performed for a plurality of frequency bands. Therefore, in this system, as shown in FIG. 1, it is possible to further include a plurality of configurations including the above-described plurality of encoders 1, multiplexing units 2, and modulators 3. Each modulator 3 performs modulation in different frequency bands. The modulated signals output from these modulators 3 are respectively supplied to the transmission equipment 4.

  The modulated signal is converted into a radio wave and transmitted from the transmission facility 4 to the communication satellite 5. The communication satellite 5 is equipped with a transponder (satellite repeater). This transponder relays radio waves in a predetermined frequency band. By mounting a plurality of transponders having different frequency bands corresponding to each other on the communication satellite 5, relay of radio waves in a plurality of frequency bands can be performed simultaneously. It can be carried out. For example, 28 transponders are mounted on the communication satellite 5. Therefore, when transmitting from the transmission facility 4 to the communication satellite 5, radio waves in a plurality of frequency bands corresponding to the number of transponders mounted on the communication satellite 5 are transmitted simultaneously.

  In many cases, each of the plurality of transponders is operated by different operators.

  The radio wave transmitted from the transmission facility 4 and relayed by the communication satellite 5 is received by the antenna 7 of the receiver 6 to be a received signal. The received signal is supplied to the tuner 8 and is subjected to predetermined signal processing, which will be described later, in the demodulator 9, error corrector 10, demultiplexer 11, MPEG decoder 12, etc., and video and audio signals are output. Predetermined data is obtained.

  FIG. 3 shows an example of a more detailed configuration of the receiver 6. A reception signal received by the antenna 7 is supplied to the tuner 8. A transponder to be received by the tuner 8 is designated, and a predetermined frequency band is selected. The selected received signal is supplied to the demodulator 9 and subjected to QPSK demodulation processing. The error corrector 10 corrects the error and restores the transport packet. The error correction unit 10 decodes the Reed-Solomon code and corrects the error. This transport packet is supplied to the separation unit 11.

  The separation unit 11 separates a packet of a desired channel, descrambles the packet, and further separates into video data, audio data, and additional data (including program information) based on information in the header part. The The video data is decoded by the video decoding unit 12V, and a received video signal is generated. The audio data is decoded by the audio decoding unit 12A, and a received audio signal is generated. These video decoding unit 12V and audio decoding unit 12A are included in the MPEG decoder 12 (see FIG. 1). The additional data is supplied to the device control unit 20. The decoded video signal is added with the display signal in the adder 25, and the output video signal of the adder 25 is displayed on the display. Similarly, the decoded audio signal is amplified by, for example, an amplifier and output from a speaker.

  The device control unit 20 controls the operation of the entire receiver and is constituted by a microcomputer. A ROM 21, a flash memory 22, a RAM 23, and a screen display generation unit 24 are coupled to the device control unit 20. The ROM 21 stores a download control program. Download control performed by the device control unit 20 is performed based on a program stored in the ROM 21. The flash memory 22 stores a normal operation control program. Control of normal operation performed by the device control unit 20 (that is, control other than download control) is performed based on a program stored in the flash memory 22. The RAM 23 is used as a temporary storage unit when the flash memory 22 is rewritten. The screen display generation unit 24 generates various display signals under the control of the device control unit 20. This display signal is supplied to the adder 25 and superimposed on the decoded video signal.

  In the present invention, a program for controlling the receiver 6 as described above is transmitted via the communication satellite 5 described above. That is, program data is supplied as additional data to the encoder 1, processed as described above, transmitted from the transmission equipment 4 together with video and audio that have been highly efficient encoded by MPEG 2, and relayed by the communication satellite 5. Is done. The user can update the program of the receiver 6, for example, by receiving the transmitted program data by the receiver 6.

  When downloading a program in the receiver 6, the program information separated by the separation unit 11 is written into the RAM 23 by the device control unit 20. Writing is performed for each rewriting unit (for example, 64 kbytes). The RAM 23 holds this information until the processing for one rewriting unit in the flash memory 22 is completed. A program for one rewrite unit is read from the RAM 23 and then written to the flash memory 22 to be rewritten. This process of one rewriting unit is repeated until rewriting of all programs to be downloaded is completed.

  FIG. 4 shows an example of the structure of a data stream for transmitting program data. In this example, the program data is made in accordance with the private section format defined in MPEG2 Systems (ISO 13818-1). In MPEG2, a data stream is handled in a unit called a pack in which a plurality of packets are bundled. This pack includes sections and PES (Packtized Elementary) based on the type of stream to be transmitted and the data configuration. Stream) Two types of packets are provided. Control information and the like are transmitted in the section, and video and audio are transmitted in the PES packet.

  In the section, parts other than the header are also defined based on the MPEG2 standard, for example, a PAT (Program Association Table), a PMT (Program Map Table), and a CAT (Conditional Access Table) in which program specification information is transmitted. ) And the above private section in which only the header is defined. Further, a plurality of sections, for example, 1024, are collected to form one table. In this embodiment, program data is stored and transmitted for this private section.

  There are two types of private sections: a short with a header size of 3 bytes and a long with an 8-byte header. Program data is stored in a short private section. The head is composed of the first five areas, that is, the table ID, section syntax indicator, private indicator, reserved area, and section length. In the remaining part, program data and other necessary data are stored.

  This section where the program data is stored is called the load section. A table ID having 8 bits defines the contents of this section. In this case, a value indicating that this section is a load section is stored. The next section syntax indicator indicates by one bit whether the header type of this section is short or long. For example, if this value is “1”, it is long, and if it is “0”, it is short. The private indicator indicates whether this section is a private section, and is a private section with a value of '1'. '11' is stored in the 2-bit reserved area.

  The next section length stores the number of bytes of this section immediately after 12 bits defined as the section length. The header ends with this section length. Since 12 bits are assigned to the section length, up to 4096 bytes can be expressed. That is, data of up to 4096 bytes can be stored after this section length area.

  The manufacturer ID has 8 bits and represents a receiver manufacturer identification number for identifying the manufacturer of the receiver. That is, different receiver manufacturer identification numbers are assigned in advance to receiver manufacturers. The next model ID having 8 bits represents a model identification number for identifying the model of the receiver. This model identification number can be uniquely assigned to each manufacturer. That is, if the manufacturer (receiver manufacturer identification number) is different, the same model identification number may exist. A receiver can be specified by combining these manufacturer ID and model ID.

  The version ID has 8 bits and represents the version of the program data transmitted in this private section. That is, the version identification number of the program data corresponding to the model specified by the manufacturer ID and the model ID is represented by this version ID.

  The next extension section number has 16 bits and represents the section number Sno assigned to this section. The subsequent extended final section number has 16 bits and represents the total number Ssum of sections having the same table ID, the same manufacturer ID, the same model ID, and the same version ID.

  The next 8 bits are used as a code data area to store the main body of program data. A plurality of, for example, N code / data areas can be provided continuously in the same section. Therefore, (8 × N) bits of program data can be transmitted per section.

  As described above, since the maximum size of data that can be stored after the header is limited to 4096 bytes in the section length, N is set to 4085 at maximum by subtracting the size of other data. Actually, since the total size of the program data is about 2 Mbytes, for example, the transmission of the program data is divided into a plurality of load sections. A different section number Sno is assigned to each of the divided load sections. In this case, the section number Sno is convenient for subsequent processing if it is given a serial number from the beginning of the program data.

  CRC-32 having the last 32 bits is a CRC (Cyclic Redundancy Check) based on data up to immediately before CRC-32 in this section. Error detection of this section is performed based on the information of the CRC-32 area.

  As described above, the communication satellite 5 is equipped with a plurality of transponders, and these plural transponders can simultaneously transmit in different frequency bands. In this case, the same program data is not transmitted from each of the plurality of transponders, and there is a high possibility that program data corresponding to a receiver of a different manufacturer or model is transmitted for each transponder. For example, from transponder A, model b of manufacturer a, from transponder B model d of manufacturer c and model f of manufacturer e, and from transponder C, model g of manufacturer a and model of manufacturer h. Like i, program data corresponding to different manufacturers and models are transmitted.

  Therefore, it is necessary to determine from which transponder the necessary program data is transmitted. FIG. 5 shows the configuration of a data stream for transmitting information indicating which transponder is sending program data corresponding to which manufacturer and model. Again, a private section is used, similar to the transmission of program data described above. However, in this example, a long header type is used.

  This section is referred to as the load control section. This load control section is transmitted with the same contents from each transponder. The first 3 bytes of the header represent the same content as the load section described above. Of course, a value indicating the load control section is used for the table ID, and the section syntax indicator is set to “1” to indicate that the header type is long.

  The reserved area having the next 18 bits is filled with '1'. The version ID, current next indicator, section number, and final section number following this reserved area are values specified by MPEG2. The header ends with this last section number.

  The transport stream ID having 16 bytes represents the number Tno of the transponder mounted on the communication satellite 5. Hereinafter, the area from the transport stream ID to immediately before CRC-32 is provided by being repeated by the number of transponders (L in this example). That is, the information shown in each of the areas immediately before CRC-32 from this transport stream ID corresponds to the data transmitted from the transponder represented by this transport stream ID.

  The next 3-bit reserved area is filled with “1”. The next down-load PID having 13 bits represents the PID when the load section is transmitted from the transponder represented by the transponder number Tno. The next 4-bit reserved area is filled with “1”.

  The model information length having 12 bytes represents the number of bytes from immediately after this to immediately before the last CRC-32 area. The following manufacturer ID and model ID each have 8 bits and represent a receiver manufacturer identification number and a model identification number, respectively. This indicates to which model by which manufacturer the program data transmitted from the transponder represented by the transponder number Tno corresponds. The manufacturer ID and model ID are repeated according to the type of program data to be transmitted. In this example, M types of data are transmitted, and the manufacturer ID and model ID are repeated M times.

  CRC-32 having the last 32 bits is a CRC (Cyclic Redundancy Check) based on data up to immediately before the CRC-32 area in this section. Error detection of this section is performed based on the information of the CRC-32 area.

  By configuring the data stream in this way, the user can automatically download the appropriate program data simply by instructing the receiver 6 to download the data stream. That is, by receiving a load control section in which the same content is transmitted from each transponder, the transponder number Tno to which appropriate program data is transmitted can be known. Based on the transponder number Tno, the receiver 6 automatically designates the transponder. The load section transmitted from the transponder is received, and whether or not the load section is appropriate is determined from the manufacturer ID, model ID, version ID, and the like. If appropriate, a download is performed.

  Next, the download process will be described in detail with reference to the flowcharts shown in FIGS. FIG. 6 shows a process for designating a transponder to which a load section corresponding to the receiver 6 is transmitted. First, in the first step S1, an arbitrary transponder is designated and reception is performed. As described above, the received radio wave is subjected to predetermined signal processing by the tuner 8 and the demodulator 9, error-corrected by the error corrector 10, and a stream of additional data is extracted by the separator 11. This additional data stream is stored in a predetermined area of the RAM 23 via the device control unit 20, for example.

  The processing after the next step S2 is performed under the control of the device control unit 20. In step S2, the data stored in the CRC-32 area is extracted from the additional data stream stored in the RAM 23. Then, a CRC calculation is performed, and it is determined whether or not there is an error in the transmitted data. If an error is detected, the process returns to step S1 to receive again. If there is no error, the process proceeds to step S2. In step S2, a table ID is acquired from the received data.

  Based on the acquired table ID, it is determined whether or not the received data is a load control section (step S4). If it is determined that it is not the load control section, the process returns to step S1.

  Although not shown, in this step S4, for example, a private indicator included in the header information as shown in FIGS. 4 and 5 is also used as a determination condition.

  On the other hand, if it is determined in step S4 that the received data is a load control section, the process proceeds to step S5. Thereafter, processing is performed based on the format shown in FIG. In step S5, the section length is acquired. In the next step S6, the transponder number Tno is set to an initial value, for example, Tno1. Subsequently, the download PID at the transponder number Tno1 is acquired at step S7, and the model information length at the transponder number Tno1 is acquired at the next step S8.

  In step S9, the manufacturer ID and model ID of the program data transmitted from the transponder indicated by the transponder number Tno1 are acquired. The process in step S9 is repeated based on the model information length obtained in step S7 based on the determination in step S10 (in this example, it is repeated M times). If it is determined that the process has been completed for the transponder number Tno1, the process proceeds to the next step S11 to determine whether the process has been completed for each transponder. If it is determined that the process has not been completed, the transponder number Tno is set to the next number, for example, Tno2 (step S12), and the process returns to step S7.

  If it is determined in step S11 that the processing for each transponder has been completed, a series of processing is completed. By performing the processing shown in the flowchart of FIG. 6, the correspondence between the transponder and the receiver manufacturer identification number (maker ID) and model identification number (model ID) of the program data transmitted from the transponder Is obtained. FIG. 7 shows an example of this correspondence. In the receiver 6, the tuner 8 is controlled by the device control unit 20 based on this correspondence, and a predetermined transponder is designated.

  That is, the device control unit 20 reads out the manufacturer ID and model ID of the receiver 6 from the ROM 21, and refers to the correspondence as shown in FIG. Thereby, the transponder to which the program data corresponding to the read manufacturer ID and model ID is transmitted can be known.

  FIG. 8 shows a flowchart when the radio wave from the designated transponder is received and the program is downloaded. First, in a first step S20, a predetermined transponder obtained by the above correspondence is specified and reception is performed. The above-described processing is performed on the received radio wave, and a stream of additional data is extracted and stored in the RAM 23.

  The processing after the next step S21 is performed under the control of the device control unit 20. In step S21, the data stored in the CRC-32 area is extracted from the additional data stream stored in the RAM 23. Then, a CRC calculation is performed, and it is determined whether or not there is an error in the transmitted data. If an error is detected, the process returns to step S20 and is received again. If there is no error, the process proceeds to step S22. In step S22, a table ID is acquired from the received data.

  Based on the acquired table ID, it is determined whether or not the received data is a load section (step S23). If it is determined that it is not a load section, the process returns to step S20.

  Although not shown, in this step S23, for example, a private indicator included in the header information as shown in FIGS. 4 and 5 is also used as a determination condition.

  On the other hand, if it is determined in step S23 that the received data is a load section, the program data is transmitted in this section. Therefore, based on the format shown in FIG. Is processed. In the next step S24, the section length is acquired. Then, in the next step S25, the manufacturer ID, model ID, and version ID are acquired, and in step S26, it is determined whether or not the program data transmitted in this load section should be downloaded. .

  First, the device control unit 20 reads the manufacturer ID and model ID from the ROM 21. It is determined whether or not the read manufacturer ID and model ID match the manufacturer ID and model ID acquired in step S24. If no match is found, it is assumed that the target program data is not transmitted in this load section.

  If they match, next, the version ID of the program data currently stored is read from the flash memory 22. This version ID is set as an attribute of the program data when the program data is stored in the flash memory 22, for example. This version ID is compared with the version ID acquired in step S24. If the acquired version ID is newer as a result of the comparison, it is determined that the target program data is transmitted in this load section, and the process proceeds to step S27.

  By comparing the version IDs, it is possible to avoid downloading the program data of the same version as the program data currently stored in the flash memory 22 or the older version of the program data.

  In step S27, the section number Sno and the total section number Ssum are acquired. The section number Sno and the total section number Ssum are stored in the RAM 23, for example, and are held until all the program data is completely downloaded. In the next step S28, it is determined whether or not the currently received load section is an unacquired section. This determination is made based on the section number Sno.

  For example, every time a load section is received, the section number Sno acquired in step S27 is cumulatively stored in the RAM 23, and a section number table of acquired load sections is created. This is done by referring to this table every time a new section number Sno is acquired.

  If it is determined in step S28 that the section is not an unacquired section, the process returns to step S20, and the next load section is received. On the other hand, if it is determined that the section is an unacquired section, the process proceeds to step S29, where program data is acquired from the data code area, and the program body is downloaded. The downloaded program data is temporarily stored in a predetermined area of the RAM 23, for example.

  As shown in FIG. 4, the program data is divided and stored in N areas having a size of 8 bits. The size of the program data stored in this load section can be known from the section length obtained in step S24 described above, and the value of N can be known. Based on the value of N, it is determined in step S30 whether program data has been downloaded by a predetermined size in this section. If the download of the predetermined size has not been completed, the process returns to step S29 and the download is continued.

  On the other hand, if it is determined in step S30 that downloading of a predetermined size has been completed, the process proceeds to step S31. In this step S31, it is determined whether or not downloading of a series of load sections in which the program data is stored has been completed. This is done, for example, by referring to the section number Sno stored cumulatively in the RAM 23 described above. If it has not been completed, the process returns to step S20, and the remaining sections are downloaded.

  On the other hand, if it is determined in step S31 that a series of load sections have been downloaded, it is assumed that the entire program data has been downloaded, and the series of processes is completed.

  When the downloading of the entire program data is completed, the program data stored in the RAM 23 is transferred and written to the flash memory 22 by a predetermined method. This is performed based on a loader program stored in advance in the ROM 21, for example.

  Further, it is more preferable to display the progress of the down-load during the above-described down-load process. This is easily calculated from the total number of sections Ssum, the cumulatively stored section number Sno, the section length acquired in step S4, and the number of repetitions of steps S29 and S30, for example, along with the execution of step S29 in FIG. can do. As a result, it is possible to display what percentage of the program data is currently downloaded as shown in FIG. 9 as an example. This display is performed by creating a display screen in the screen display generation unit 24 based on the control of the device control unit 20 and combining it with the output from the video signal unit 12 in the adder 25.

  In the above description, the program data is downloaded, but this is not limited to this example. For example, it is easy to transmit a message such as new product or program update information from a receiver manufacturer using data to be transmitted as text data, still images, or moving image data.

It is a block diagram which shows an example of the data transmission system applicable to this one Embodiment. It is a basic diagram for demonstrating a transport packet. It is a block diagram which shows an example of the further detailed structure of a receiver. It is a basic diagram which shows an example of a structure of a load section. It is a basic diagram which shows an example of a structure of a load control section. It is a flowchart which shows the process at the time of designating the transponder in which the load section corresponding to a receiver is transmitted. It is a basic diagram for demonstrating the correspondence of a transponder, the receiver manufacturer identification number of a program data transmitted from the transponder, and a model identification number. It is a flowchart at the time of receiving the radio wave from the designated transponder and downloading the program. It is an approximate line figure showing an example of a display of progress in the middle of a down load. It is a figure which shows the outline of a typical digital broadcasting system.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Encoder, 2 ... Multiplexing part, 3 ... Modulator, 4 ... Transmission equipment, 5 ... Communication satellite, 6 ... Receiver, 11 ... Separation part, 20 ... Device control unit, 21 ... ROM, 22 ... Flash memory, 23 ... RAM

Claims (2)

Video signal, audio signal and additional data are divided into a predetermined length packets, the packet a plurality of transport stream multi duplex is modulated at different frequencies, the modulated plurality of transport streams of a predetermined frequency Receiving means for receiving a broadcast signal from the transponder relayed by a transponder that relays radio waves in a band;
Demodulation means for demodulating the broadcast signal received by the received signal;
Separating means for restoring the packet from the broadcast signal demodulated by the demodulating means , and separating the video signal, audio signal and additional data from the packet ;
From the additional data separated by the separation means, a transport stream ID indicating which transponder has been transmitted, a version ID of the download content for update , manufacturer identification information and model identification information of the receiving device are extracted. Extraction means;
Based on the said transport stream ID extracted by the extracting means identifies the transponder, to control the reception means to receive a broadcast signal from the identified transponder, received by said receiving means the Download update download content included from the broadcast signal based on the said transport stream to the manufacturer identification information and model identification information extracted by the extracting means, the program data stored with the version ID version A receiving apparatus comprising: a control unit that compares IDs and updates program data in the receiving apparatus when they match . Video signal, audio signal and additional data are divided into a predetermined length packets, the packet a plurality of transport stream multi duplex is modulated at different frequencies, the modulated plurality of transport streams of a predetermined frequency A reception step of receiving a broadcast signal from the transponder by a receiving means, relayed by a transponder that relays radio waves in a band;
A demodulation step of demodulating the broadcast signal received by the received signal;
A separation step of restoring the packet from the broadcast signal demodulated by the demodulation step , and separating the video signal, audio signal, and additional data from the packet ;
From the additional data separated by the separation step, a transport stream ID indicating which transponder has been transmitted, a version ID of the download content for update , manufacturer identification information and model identification information of the receiving device are extracted. An extraction step;
Based on the said transport stream ID extracted by the extraction step identifies the transponder, to control the reception means to receive a broadcast signal from the identified transponder, received by the receiving step above Download update download content included from the broadcast signal based on the said transport stream to the manufacturer identification information and model identification information extracted by the extraction step, the program data stored with the version ID version And a control step of updating the program data in the receiving apparatus when the IDs are compared and matched .

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