JP7658401B2 - Transmitting device and transmitting method - Google Patents

Description

The present technology relates to a transmission device and a transmission method , and in particular to a transmission device and a transmission method that are capable of reliably notifying the start position of a transmission packet or a transmission stream when encapsulating the transmission packet or the transmission stream into an error correction block .

For example, one broadcasting format for terrestrial digital television broadcasting is ISDB-T (Integrated Services Digital Broadcasting - Terrestrial), which is used in Japan and other countries (see, for example, Non-Patent Document 1).

Also, a variable-length packet called a TLV (Type Length Value) packet is known as a transmission packet for transmitting video and audio data (see, for example, Non-Patent Document 2).

ARIB STD-B31 Version 2.2 Association of Radio Industries and Businesses ARIB STD-B44 Version 2.1 Association of Radio Industries and Businesses

Incidentally, studies are being conducted to improve the next generation of terrestrial digital television broadcasting. For the next generation of terrestrial digital television broadcasting, data transmission using TLV packets as transmission packets is being considered.

Here, transmission packets such as TLV packets and transmission streams are encapsulated in error correction blocks such as FEC blocks and transmitted, but the technical method for encapsulating transmission packets or transmission streams in error correction blocks has not been established. Therefore, there has been a demand for a proposal for reliably notifying the beginning position of a transmission packet or transmission stream when the transmission packet or transmission stream is encapsulated in an error correction block.

This technology was developed in consideration of these circumstances, and makes it possible to reliably notify the beginning position of a transmission packet or a transmission stream when the transmission packet or the transmission stream is encapsulated in an error correction block.

The transmitting device of the present technology includes a first generating unit that generates an FEC (Forward Error Correction) block based on an input packet or an input stream, a second generating unit that generates an FEC frame based on the FEC block, and a transmitting unit that transmits the FEC frame, and the header of the FEC block includes a minimum fixed-length header having type identification information that identifies the type of the input packet or the input stream, information that detects a header error, and position information of the beginning of the input packet or the input stream that is stored in the payload of the FEC frame.

The transmission method of the present technology includes generating an FEC block based on an input packet or an input stream, generating an FEC frame based on the FEC block, and transmitting the FEC frame, and the header of the FEC block includes a minimum fixed-length header having type identification information for identifying the type of the input packet or the input stream, information for detecting a header error, and position information of the beginning of the packet of the input packet or the input stream that is stored in the payload of the FEC frame.

In the transmission device and transmission method of the present technology, an FEC block is generated based on an input packet or an input stream, and an FEC frame is generated and transmitted based on the FEC block. The header of the FEC block includes type identification information that identifies the type of the input packet or the input stream, information that detects header errors, and a minimum fixed-length header that has position information of the beginning of the input packet or the input stream packet that is stored in the payload of the FEC frame.

The receiving device of the present technology includes a receiving unit that receives a signal consisting of an FEC frame transmitted, a first generating unit that generates an FEC block based on the received FEC frame, and a second generating unit that generates an input packet or an input stream based on the FEC block, and the header of the FEC block includes type identification information that identifies the type of the input packet or the input stream, and a minimum fixed-length header that has position information of the beginning of the input packet or the input stream that is stored in the payload of the FEC frame.

The reception method of the present technology includes receiving a signal consisting of an incoming FEC frame, generating an FEC block based on the received FEC frame, and generating an input packet or an input stream based on the FEC block, and the header of the FEC block includes a minimum fixed-length header having type identification information that identifies the type of the input packet or the input stream, and position information of the beginning of the input packet or the input stream that is stored in the payload of the FEC frame.

In the receiving device and receiving method of the present technology, a signal consisting of transmitted FEC frames is received, and an FEC block is generated based on the received FEC frames. Then, an input packet or an input stream is generated based on the FEC block. The header of the FEC block includes type identification information that identifies the type of the input packet or the input stream, and a minimum fixed-length header that has position information of the beginning of the input packet or the input stream that is stored in the payload of the FEC frame.

This technology makes it possible to reliably notify the beginning position of a transmission packet or a transmission stream when the transmission packet or the transmission stream is encapsulated in an error correction block.

Note that the effects described here are not necessarily limited to those described herein and may be any of the effects described in this disclosure.

1 is a block diagram showing a configuration of an embodiment of a transmission system to which the present technology is applied. 2 is a block diagram showing an example of the configuration of a data processing device and a transmission device; FIG. 2 is a block diagram showing a configuration example of a receiving device. FIG. 1 is a diagram illustrating the background of the present technology. FIG. 1 is a diagram illustrating a problem that the present technology solves. FIG. 1 is a diagram outlining a method for solving the problem. FIG. 1 is a diagram for explaining an overview of generation of FEC blocks. FIG. 2 is a diagram illustrating an example of an FEC block. A figure showing a first example of the size of a baseband frame. A figure showing a second example of the size of a baseband frame. A figure showing a third example of the size of a baseband frame. FIG. 2 is a diagram for explaining an overview of a data format employed in the present technology. 1 is a diagram illustrating an example of a first format of data employed in the present technology. 1 is a diagram illustrating an example of a first format of data employed in the present technology. 1 is a diagram illustrating an example of a first format of data employed in the present technology. 1 is a diagram illustrating an example of a first format of data employed in the present technology. 1 is a diagram illustrating an example of a first format of data employed in the present technology. 1 is a diagram illustrating an example of a first format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a second format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a second format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a third format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a third format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a third format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a third format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a third format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a third format of data employed in the present technology. FIG. 11 is a diagram illustrating an example of a fourth format of data employed in the present technology. FIG. 2 is a diagram illustrating an example of NTP transmission timing. FIG. 2 is a block diagram showing an example of a configuration of blocks involved in generating FEC blocks. FIG. 1 is a diagram illustrating a flow of generating an FEC block. 13 is a diagram illustrating the maximum value of the head TLV packet position pointer when the baseband frame size is a middle code. 13 is a diagram illustrating the maximum value of the first TLV packet position pointer when the baseband frame size is a long code. 13 is a diagram for explaining the maximum value of the head TLV packet position pointer when the baseband frame size is a short code. FIG. 13 is a diagram illustrating an example of the format of a Format 1 FEC block header. FIG. 13 is a diagram showing an example of the format of an EXT byte of format 1. FIG. 13 is a diagram showing an example of padding values of Format 1. FIG. 13 is a diagram for explaining simplification of the illustration of an FEC block header. FIG. 13 is a diagram showing a detailed example 1 of Format 1. FIG. 13 is a diagram showing a detailed example 1 of Format 1. FIG. 13 is a diagram showing a detailed example 2 of format 1. FIG. 13 is a diagram showing a detailed example 2 of format 1. FIG. 13 is a diagram showing a detailed example 3 of format 1. FIG. 13 is a diagram showing a detailed example 3 of format 1. FIG. 13 is a diagram showing an example of the format of an FEC block header of format 2-1. A figure showing an example of padding values of format 2-1. FIG. 13 is a diagram showing an example of the format of an FEC block header of format 2-2. A figure showing an example of padding values of format 2-2. FIG. 13 is a diagram illustrating an example of the format of a Format 3 FEC block header. FIG. 13 is a diagram showing an example of the format of an EXT byte in Format 3. FIG. 13 is a diagram showing an example of a padding value of Format 3. FIG. 13 is a diagram showing an example of the format of an FEC block header of format 3-1. A figure showing an example of padding values of format 3-1. A diagram showing an example of the format of the EXT byte of format 3-1. A figure showing a detailed example 1 of format 3-1. A figure showing a detailed example 1 of format 3-1. A figure showing a detailed example 1 of format 3-1. A figure showing a detailed example 2 of format 3-1. A figure showing a detailed example 2 of format 3-1. A figure showing detailed example 3 of format 3-1. A figure showing detailed example 3 of format 3-1. FIG. 13 is a diagram illustrating an example of the format of an FEC block header of Format 4. FIG. 13 is a diagram showing an example of the format of an EXT byte in Format 4. FIG. 13 is a diagram showing an example of padding values of Format 4. FIG. 11 is a diagram showing an example of timing for sending time information. 11 is a flowchart illustrating the operation of the transmitting side and the receiving side. FIG. 2 is a block diagram showing an example of the configuration of a computer.

Below, we will explain the embodiment of this technology with reference to the drawings. The explanation will be given in the following order.

1. System configuration 2. Overview of the present technology 3. Detailed contents of the present technology (3-1) First format (3-2) Second format (3-3) Third format (3-4) Fourth format 4. Timing of sending time information of the present technology 5. Operation of the transmitting side and the receiving side 6. Modification 7. Computer configuration

＜1. System configuration＞

(Example of a transmission system configuration)
1 is a block diagram showing a configuration of an embodiment of a transmission system to which the present technology is applied. Note that the term "system" refers to a logical collection of multiple devices.

In FIG. 1, the transmission system 1 is composed of data processing devices 10-1 to 10-N (N is an integer equal to or greater than 1) installed in facilities related to each broadcasting station, a transmitting device 20 installed at a transmitting station, and receiving devices 30-1 to 30-M (M is an integer equal to or greater than 1) owned by users.

In addition, in this transmission system 1, the data processing devices 10-1 to 10-N and the transmitting device 20 are connected via communication lines 40-1 to 40-N. Note that the communication lines 40-1 to 40-N can be, for example, dedicated lines.

The data processing device 10-1 processes content such as broadcast programs produced by broadcast station A, and transmits the resulting transmission data to the transmitting device 20 via the communication line 40-1.

In data processing devices 10-2 to 10-N, similar to data processing device 10-1, content such as broadcast programs produced by each broadcast station, such as broadcast station B and broadcast station Z, is processed, and the resulting transmission data is transmitted to transmitting device 20 via communication lines 40-2 to 40-N.

The transmitting device 20 receives transmission data transmitted from the data processing devices 10-1 to 10-N on the broadcasting station side via the communication lines 40-1 to 40-N. The transmitting device 20 processes the transmission data from the data processing devices 10-1 to 10-N, and transmits the resulting broadcast signal from a transmitting antenna installed at the transmitting station.

As a result, the broadcast signal from the transmitting device 20 at the transmitting station is transmitted to the receiving devices 30-1 through 30-M via the broadcast transmission path 50.

The receiving devices 30-1 to 30-M are fixed receivers such as television receivers, set-top boxes (STBs), recorders, game consoles, and network storage, or mobile receivers such as smartphones, mobile phones, and tablet computers. The receiving devices 30-1 to 30-M may also be in-vehicle devices mounted on vehicles, such as in-vehicle televisions, or wearable computers such as head mounted displays (HMDs).

The receiving device 30-1 receives and processes the broadcast signal transmitted from the transmitting device 20 via the broadcast transmission path 50, thereby playing back content such as a broadcast program in response to a channel selection operation by the user.

In the receiving devices 30-2 to 30-M, the broadcast signal from the transmitting device 20 is processed in the same manner as in the receiving device 30-1, and content corresponding to the channel selection operation by the user is played back.

In the transmission system 1, the broadcast transmission path 50 is described as being terrestrial waves (terrestrial broadcasting), but it is not limited to terrestrial waves and may be, for example, satellite broadcasting using a broadcasting satellite (BS: Broadcasting Satellite) or a communications satellite (CS: Communications Satellite), or cable broadcasting using a cable (CATV: Common Antenna TeleVision).

In addition, although not shown in the figure, in the transmission system 1, various servers may be connected to a communication line such as the Internet, and the receiving devices 30-1 to 30-M having communication capabilities may access the various servers via a communication line such as the Internet and perform two-way communication to receive various data such as content and applications.

In the following description, the data processing devices 10-1 to 10-N on the broadcasting station side will be referred to as data processing devices 10 unless there is a need to distinguish them. Also, the receiving devices 30-1 to 30-M will be referred to as receiving devices 30 unless there is a need to distinguish them.

(Configuration of the transmitting device)
FIG. 2 is a block diagram showing an example of the configuration of the data processing device 10 and the transmission device 20 shown in FIG.

In FIG. 2, the data processing device 10 is composed of a component processing unit 111, a signaling generation unit 112, a multiplexer 113, and a data processing unit 114.

The component processing unit 111 processes the component data that constitutes the content of a broadcast program or the like, and supplies the resulting component stream to the multiplexer 113. Here, the component data is, for example, video, audio, subtitles, etc., and processing such as encoding that complies with a predetermined encoding method is performed on this data.

The signaling generation unit 112 generates signaling used in higher layer processing such as content selection and playback, and supplies it to the multiplexer 113. The signaling generation unit 112 also generates signaling used in physical layer processing such as broadcast signal modulation and demodulation, and supplies it to the data processing unit 114.

Signaling is also referred to as control information. In the following description, the signaling used in physical layer processing is referred to as physical layer signaling (L1 signaling), while the signaling used in upper layer processing, which is a layer higher than the physical layer, is referred to as upper layer signaling to distinguish between the two.

The multiplexer 113 multiplexes the component stream supplied from the component processing unit 111 and the upper layer signaling stream supplied from the signaling generation unit 112, and supplies the resulting stream to the data processing unit 114. Note that other streams such as applications and time information may also be multiplexed here.

The data processing unit 114 processes the stream supplied from the multiplexer 113 to generate packets (frames) of a specified format. The data processing unit 114 also processes the packets of the specified format and the physical layer signaling from the signaling generation unit 112 to generate transmission data, which it then transmits to the transmitting device 20 via the communication line 40.

In FIG. 2, the transmitting device 20 is composed of a data processing unit 211 and a modulation unit 212.

The data processing unit 211 receives and processes the transmission data sent from the data processing device 10 via the communication line 40, and extracts the resulting packets (frames) of a specified format and physical layer signaling information.

The data processing unit 211 processes packets (frames) of a specified format and physical layer signaling information to generate physical layer frames (physical layer frames) that conform to a specified broadcasting method (e.g., next-generation terrestrial digital television broadcasting) and supplies them to the modulation unit 212.

In the configuration of FIG. 2, the physical layer signaling is generated on the data processing device 10 side and transmitted to the transmitting device 20, but the physical layer signaling may be generated on the transmitting device 20 side.

The modulation unit 212 performs necessary processing (e.g., modulation processing, etc.) on the physical layer frame supplied from the data processing unit 211, and transmits the resulting broadcast signal (RF signal) from a transmitting antenna installed at the transmitting station.

The data processing device 10 and the transmission device 20 are configured as described above.

(Configuration of the receiving device)
FIG. 3 is a block diagram showing an example of the configuration of the receiving device 30 in FIG.

In FIG. 3, the receiving device 30 is composed of a tuner 311, a demodulation unit 312, and a data processing unit 313.

The tuner 311 performs the necessary processing on the broadcast signal (RF signal) received via the antenna 321 and supplies the resulting signal to the demodulation unit 312.

The demodulation unit 312 is configured as a demodulator such as a demodulation LSI (Large Scale Integration). The demodulation unit 312 performs demodulation processing on the signal supplied from the tuner 311. In this demodulation processing, for example, a physical layer frame is processed in accordance with physical layer signaling, and a packet in a predetermined format is obtained. The packet obtained as a result of this demodulation is supplied to the data processing unit 313.

The data processing unit 313 is configured, for example, as a system on chip (SoC). The data processing unit 313 performs predetermined processing on the packets supplied from the demodulation unit 312. Here, for example, stream decoding processing and playback processing are performed based on higher layer signaling obtained from the packets.

The video, audio, subtitles, and other data obtained by processing in the data processing unit 313 is output to a downstream circuit. As a result, the receiving device 30 plays content such as a broadcast program, and outputs the video and audio.

The receiving device 30 is configured as described above.

＜2. Overview of this technology＞

The transmitting device 20 and the receiving device 30 have the following functions.

That is, the transmitting device 20 includes a first generating unit that generates an FEC (Forward Error Correction) block based on an input packet or an input stream, a second generating unit that generates an FEC frame based on the FEC block, and a transmitting unit that transmits the FEC frame.

The header of the FEC block includes type identification information that identifies the type of input packet or input stream, and a minimum fixed-length header that has position information of the beginning of the input packet or input stream that is stored in the payload of the FEC frame.

When the type identification information is a TLV (Type Length Value) packet, the minimum fixed length header includes, in addition to the type identification information, minimum fixed length identification information that identifies whether the input packet length of the input packet is the minimum fixed length, and the minimum input packet length as information on the input packet length.

If the minimum fixed length identification information indicates that the input packet length is not the minimum fixed length, the header includes a variable length header in addition to the minimum fixed length header. The variable length header includes variable length packet length information consisting of the upper bits of the input packet length when the lower bits of the input packet length are taken as minimum input packet length information indicating the minimum input packet length.

In the transmitting device 20 having the above functions, an FEC block is generated based on the input packet or input stream, and an FEC frame is generated from the FEC block and transmitted.

The transmitting device 20 can transmit an OFDM (Orthogonal Frequency Division Multiplexing) frame in which an FEC frame is placed, and can further include a third generating unit that generates a dummy cell for placing time information at the beginning of the OFDM frame. In this case, the transmitting device 20 can place a dummy cell in the OFDM frame as necessary, thereby placing time information at the beginning of the OFDM frame.

The receiving device 30 includes a receiving unit that receives a signal consisting of transmitted FEC frames, a first generating unit that generates an FEC block based on the received FEC frames, and a second generating unit that generates an input packet or an input stream based on the FEC block.

In the receiving device 30 having the above functions, a signal consisting of FEC frames is received, and an FEC block is generated based on the received FEC frame. Furthermore, an input packet or an input stream is generated based on the FEC block.

FIG. 4 is a diagram illustrating the background of the present technology.
FIG. 5 is a diagram illustrating the problem that the present technology solves.
FIG. 6 is a diagram outlining a method for solving the problem.
FIG. 7 is a diagram for explaining an overview of generation of FEC blocks.
FIG. 8 is a diagram illustrating an example of an FEC block.
FIG. 9 is a diagram showing a first example of the size of a baseband frame.
FIG. 10 is a diagram showing a second example of the size of a baseband frame.
FIG. 11 is a diagram showing a third example of the size of a baseband frame.
FIG. 12 is a diagram for explaining an outline of the data format employed in the present technology.
13, 14, 15, 16, 17, and 18 are diagrams for explaining an example of the first format of data employed in the present technology.
19 and 20 are diagrams for explaining an example of the second format of data employed in the present technology.
21, 22, 23, 24, 25, and 26 are diagrams for explaining an example of the third format of data employed in the present technology.
FIG. 27 is a diagram illustrating an example of a fourth format of data employed in the present technology.
FIG. 28 is a diagram showing an example of NTP transmission timing.

Figures 4 to 28 show an overview of this technology, and the details will be explained below with reference to Figures 29 to 64.

＜3. Detailed information about this technology＞

(FEC block configuration)
FIG. 29 is a diagram showing an example of a configuration of blocks related to generation of FEC blocks.

As shown in FIG. 29, on the transmitting side, blocks involved in generating FEC blocks include a TLV packet generator 151, a TS packet processor 152, an FEC block generator 153, and an FEC frame generator 154. However, each block from the TLV packet generator 151 to the FEC frame generator 154 is included in either the data processing device 10 (data processor 114 (FIG. 2)) or the transmitting device 20 (data processor 211 (FIG. 2)).

The TLV packet generator 151 processes the IP (Internet Protocol) stream input thereto to generate TLV packets, and supplies them to the FEC block generator 153. Here, the TLV packets include, for example, IP packets and control information (upper layer signaling). The IP packets also include UDP (User Datagram Protocol) packets.

The TS packet processing unit 152 processes the input TS stream (MPEG2-TS stream) to generate TS packets, and supplies them to the FEC block generation unit 153. Processing of this TS stream includes, for example, deleting synchronization bytes.

The FEC block generation unit 153 is supplied with TLV packets from the TLV packet generation unit 151 or TS packets from the TS packet processing unit 152. The FEC block generation unit 153 processes the TLV packets or TS packets to generate FEC blocks and supplies them to the FEC frame generation unit 154.

Here, an FEC block consists of an FEC block header (FBH) and a data section. TLV packets or TS packets are placed in the data section, but here we will explain the case where one or more TLV packets (part or all) are placed. Also, TLV packets are of variable length, and a TLV packet placed in a certain FEC block may be placed across to the next FEC block.

Note that what is placed in the data section of the FEC block is not limited to input packets (transmission packets) such as TLV packets and TS packets, but may also be input streams (transmission streams) such as IP streams and TS streams.

The FEC frame generation unit 154 performs processes such as energy diffusion, BCH (Bose-Chaudhuri-Hocquenghem) coding, and LDPC (Low Density Parity Check) coding on the FEC blocks supplied from the FEC block generation unit 153 to generate an FEC frame, which it supplies to the subsequent stage.

The FEC frame is constructed by adding the parity of the BCH code and the LDPC code to one FEC block. In other words, the variable-length TLV packet is encapsulated in a fixed-length FEC block, and then the parity of the BCH code and the LDPC code is added and stored in the fixed-length FEC frame.

(FEC block generation flow)
Fig. 30 is a diagram for explaining the flow of generating FEC blocks. Note that in Fig. 30, the time direction is from the left side to the right side in the figure.

When the TLV packet generated by the TLV packet generation unit 151 (FIG. 29) is input to the FEC block generation unit 153 (FIG. 29) (S1), an FEC block header (FBH) is added to the TLV packet, and an FEC block is generated (S2). Then, energy diffusion is performed on the FEC block thus obtained (S3).

Here, if we look at the first FEC block FB1 among the FEC blocks generated in the FEC block generation process in step S2, we see that in this FEC block FB1, following two TLV packets (all of their data), a portion of the data of one TLV packet is placed. Also, if we look at the next FEC block FB2, we see that in this FEC block FB2, following the remaining data of the TLV packet whose portion of the data was placed in FEC block FB1, the data of one or more TLV packets is placed.

That is, a certain TLV packet is placed across the first FEC block FB1 and the following FEC block FB2. In this case, it is desirable to reliably notify the position (start position) of the first TLV packet placed following the remaining data of a certain TLV packet (a TLV packet placed across FEC blocks FB1 and FB2) in FEC block FB2 so that the TLV packet in the FEC block can be reliably extracted.

Therefore, in this technology, a pointer indicating the position of the first TLV packet in an FEC block (hereinafter referred to as the first TLV packet position pointer) is placed in the FEC block header (FBH) of that FEC block, so that the position of the first TLV packet (first position P in the figure) can be reliably identified using this first TLV packet position pointer.

For example, if this technology is not applied and the first TLV packet position pointer is not placed in the FEC block header (FBH) of the FEC block, when the receiver is unable to obtain synchronization information due to some reason such as a reception error, it may not be able to extract and process the TLV packet correctly, resulting in data being cut off.

On the other hand, when this technology is applied and a first TLV packet position pointer is placed in the FEC block header (FBH) of an FEC block, the receiver can reliably identify the position of the first TLV packet for each FEC block using the first TLV packet position pointer, and can always correctly extract and process TLV packets, preventing data interruptions.

The number of bits assigned to the first TLV packet position pointer can be set to any value depending on the data configuration, etc. For example, the maximum value of the first TLV packet position pointer is determined according to the baseband frame size, so the number of bits assigned to the first TLV packet position pointer can be determined accordingly.

The following describes the number of bits to be assigned to the first TLV packet position pointer for the baseband frame sizes of Middle code with a code length of 69120 bits, Long code with a code length of 276480 bits, and Short code with a code length of 17280 bits.

(Maximum value of pointer for each code length)
FIG. 31 is a diagram for explaining the maximum value of the head TLV packet position pointer when the baseband frame size is a middle code (code length: 69120 bits).

In FIG. 31, CR (Coding Rate) represents the coding rate of the LDPC code, N_ldpc represents the LDPC code block (unit: bits), and N_bch represents the BCH code block (unit: bits). Also, in FIG. 31, BCH represents N_bch - K_bch (unit: bits), K_bch represents the BCH information block (unit: bits, bytes), and Num Bits represents the number of bits required according to K_bch (B: bytes).

As shown in FIG. 31, in the case of a middle code with N_ldpc = 69120 bits, when the coding rate (CR) of the LDPC code is 2/16 or 3/16, the number of bits (Num Bits) is 11 bits, when the coding rate (CR) of the LDPC code is 4/16, 5/16, 6/16 or 7/16, the number of bits (Num Bits) is 12 bits, and when the coding rate (CR) of the LDPC code is 8/16, 9/16, 10/16, 11/16, 12/16, 13/16 or 14/16, the number of bits (Num Bits) is 13 bits.

In this way, in the case of a middle code with a code length of 69120 bits, when the maximum coding rate is CR = 14/16, the number of bits (Num Bits) is 13 bits, so the maximum value of the first TLV packet position pointer is 13 bits.

Figure 32 is a diagram explaining the maximum value of the first TLV packet position pointer when the baseband frame size is a long code (code length: 276480 bits). Note that in Figure 32, the meanings of CR, N_ldpc, N_bch, BCH, K_bch, and Num Bits are the same as in Figure 31. In other words, here too, Num Bits represents the number of bits required according to K_bch (B: bytes).

As shown in FIG. 32, in the case of a long code with N_ldpc = 276480 bits, when the coding rate (CR) of the LDPC code is 2/16 or 3/16, the number of bits (Num Bits) is 13 bits, when the coding rate (CR) of the LDPC code is 4/16, 5/16, 6/16 or 7/16, the number of bits (Num Bits) is 14 bits, and when the coding rate (CR) of the LDPC code is 8/16, 9/16, 10/16, 11/16, 12/16, 13/16 or 14/16, the number of bits (Num Bits) is 15 bits.

In this way, in the case of a long code with a code length of 276480 bits, when the maximum coding rate is CR = 14/16, the number of bits (Num Bits) is 15 bits, so the maximum value of the first TLV packet position pointer is 15 bits.

Figure 33 is a diagram explaining the maximum value of the first TLV packet position pointer when the baseband frame size is a short code (code length: 17280 bits). Note that in Figure 33, the meanings of CR, N_ldpc, N_bch, BCH, K_bch, and Num Bits are the same as in Figure 31. In other words, here too, Num Bits represents the number of bits required according to K_bch (B: bytes).

As shown in FIG. 33, in the case of a short code with N_ldpc = 17280 bits, when the coding rate (CR) of the LDPC code is 2/16, the number of bits (Num Bits) is 8 bits, when the coding rate (CR) of the LDPC code is 3/16, the number of bits (Num Bits) is 9 bits, when the coding rate (CR) of the LDPC code is 4/16, 5/16, 6/16, or 7/16, the number of bits (Num Bits) is 10 bits, and when the coding rate (CR) of the LDPC code is 8/16, 9/16, 10/16, 11/16, 12/16, 13/16, or 14/16, the number of bits (Num Bits) is 11 bits.

In this way, in the case of a short code with a code length of 17280 bits, when the maximum coding rate is CR = 14/16, the number of bits (Num Bits) is 11 bits, so the maximum value of the first TLV packet position pointer is 11 bits.

As described above, the maximum value of the first TLV packet position pointer varies depending on the code length of each code, such as the middle code, long code, and short code, and the maximum coding rate (CR), so the length of the first TLV packet position pointer placed in the FEC block header (FBH) varies. Therefore, in this technology, the first to fourth formats are proposed as the format of the FEC block header (FBH) according to the length of the first TLV packet position pointer.

(3-1) First Format First, the configuration of the FEC block header (FBH) of the first format (hereinafter also referred to as format 1) will be described with reference to FIGS.

(FEC block header format)
FIG. 34 is a diagram showing an example of the format of a Format 1 FEC block header.

In Figure 34, the 2-byte base header consists of a 15-bit first TLV packet position pointer and a 1-bit EXT flag.

The first TLV packet position pointer is a pointer that indicates the position of the first TLV packet in the FEC block that contains the FEC block header in which it is placed. In the base header of format 1, 15 bits are reserved for this first TLV packet position pointer, so it can be used as a pointer for all code lengths, including long codes, medium codes, and short codes.

The EXT flag is a flag that indicates whether an extension area exists. For example, if '0' is specified as the EXT flag, it indicates that there is no extension. In this case, only the 2-byte base header will be placed as the FEC block header. On the other hand, if '1' is specified as the EXT flag, it indicates that there is an extension. In this case, the next byte after the base header will be the EXT byte.

If the start of a TLV packet (first TLV byte) does not exist in the target FEC block, the 15 bits of the first TLV packet position pointer are assigned the value '0x7FFF' (111 1111 1111 1111).

(EXT byte format)
FIG. 35 is a diagram showing an example of the format of the EXT byte of Format 1.

This EXT byte is placed as the next byte after the base header in Figure 34 when '1' is specified as the EXT flag in Figure 34.

In Figure 35, one EXT byte consists of a two-bit padding value, a one-bit TS flag, a one-bit CRC flag, and a four-bit reserved area.

For example, the padding value for format 1 is specified according to the contents shown in Figure 36.

In other words, if '00' is specified as the padding value, it means there is no padding. In this case, there is no additional padding. On the other hand, if '01' is specified as the padding value, it means short padding. In this case, one additional byte of padding is added.

If '10' is specified as the padding value, it means long padding. In this case, the length of the additional padding is indicated in two bytes. If '11' is specified as the padding value, it means that this is a reserved area for future use. Note that other meanings of this reserved area may also be specified, such as full padding, which means that everything is padded.

Returning to the explanation of Figure 35, the TS flag is a flag that indicates whether or not the packet placed in the FEC block is a TS packet. For example, when '0' is specified as the TS flag, this indicates that the packet is not a TS packet. In this case, a TLV packet is placed in the FEC block. On the other hand, when '1' is specified as the TS flag, this indicates that the packet is a TS packet.

The CRC flag indicates whether or not a CRC (Cyclic Redundancy Check), which is an error detection code, is present. For example, when '0' is specified as the CRC flag, it indicates that there is no CRC. On the other hand, when '1' is specified as the CRC flag, it indicates that there is a CRC. In this case, the CRC is placed immediately after the EXT byte. Note that when a CRC is added, it is always added, so the initial header size of the FEC block header in this case is 3 bytes.

Reserved space is space for future use.

Next, we will explain a more specific example of Format 1. However, in the following explanation, for the sake of simplicity, in the FEC block header and TLV packet placed in the FEC block, the FEC block and TLV packet are omitted from the illustration, and only the FEC block header is illustrated.

In other words, as shown in Figure 37, when there is no padding and the EXT flag is specified as '0', the actual configuration is as shown in Figure 37A, but in the following explanation, for simplicity, the configuration shown in Figure 37B is illustrated.

(Detailed example 1 of Format 1)
38 and 39 show a detailed example 1 of Format 1. This detailed example 1 shows a configuration in which padding is added to an FEC block header consisting of a base header and an EXT byte. In this detailed example, the length of the padding is described as "Padding".

(3-1-1A): Padding = 1, EXT = 1, TS = 0
FIG. 38A shows the configuration of an FEC block header when the EXT flag is set to '1' and the TS flag is set to '0' when the length of padding is 1 byte (1B).

In A of Figure 38, in addition to the 15-bit first TLV packet position pointer, a 1-bit EXT flag is placed in the base header, but because the EXT flag is set to '1', the next byte after the base header becomes the EXT byte as an optional header.

In this EXT byte, the first two bits are set to '00' as a padding value, and the following bit is set to '0' as a TS flag. In addition, the remaining five bits in the EXT byte are used to store bits reserved for the future, along with a CRC flag value of '0'.

In this way, in the FEC block header of A in Figure 38, 1 byte (1B) of padding is achieved by using 1 byte (1B) of EXT byte.

(3-1-1B): Padding = 2, EXT = 1, TS = 0
FIG. 38B shows the configuration of the FEC block header when the EXT flag is set to '1' and the TS flag is set to '0' when the length of padding is 2 bytes (2B).

In B of Figure 38, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first 2 bits of the padding value are set to '01', so the next byte after the EXT byte is an additional 1B padding.

In the EXT byte, the bit following the first two bits is set to '0' as the TS flag. The remaining five bits of the EXT byte are set to a CRC flag set to '0' and a bit reserved for the future.

In this way, in the FEC block header of B in Figure 38, a total of 2 bytes (2B) of padding is achieved by 1 byte (1B) of EXT byte and 1 byte (1B) of additional padding.

(3-1-C): Padding = 3, EXT = 1, TS = 0
FIG. 38C shows the configuration of the FEC block header when the EXT flag is set to '1' and the TS flag is set to '0' when the length of padding is 3 bytes (3B).

In C of Figure 38, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first two bits of the padding value are set to '10', so the next two bytes after the EXT byte indicate the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '0' ('00000000 00000000'), which means that no more padding will be added.

In the EXT byte, the bit following the first two bits is set to '0' as the TS flag. The remaining five bits of the EXT byte are set to a CRC flag set to '0' and a bit reserved for the future.

In this way, in the FEC block header of C in Figure 38, a total of 3 bytes (3B) of padding is achieved by the 1 byte (1B) of EXT byte and the 2 bytes (2B) of additional padding.

(3-1-1D): Padding = 4, EXT = 1, TS = 0
FIG. 39D shows the configuration of the FEC block header when the EXT flag is set to '1' and the TS flag is set to '0' when the length of padding is 4 bytes (4B).

In Figure 39D, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first two bits of the padding value are set to '10', so the two bytes after the EXT byte indicate the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '1' ('00000000 00000001'), so an additional byte (1B) of padding is added.

In the EXT byte, the bit following the first two bits is set to '0' as the TS flag. The five bits in the EXT byte are used to set the CRC flag, which is set to '0', and a bit reserved for the future.

In this way, in the FEC block header of Figure 39D, a total of 4 bytes (4B) of padding is achieved by 1 byte (1B) of EXT byte, 2 bytes (2B) of additional padding length, and 1 byte (1B) of additional padding.

(3-1-1E): Padding = 12348, EXT = 1, TS = 0
FIG. 39E shows the configuration of the FEC block header when the EXT flag is set to '1' and the TS flag is set to '0' when the length of the padding is 12348 bytes (12348B).

In E of Figure 39, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first two bits of the padding value are set to '10', so the two bytes after the EXT byte indicate the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '1' ('00110000 00111001'), so an additional 12345 bytes (12345B) of padding is added.

In the EXT byte, the bit following the first two bits is set to '0' as the TS flag. The five bits in the EXT byte are used to set the CRC flag, which is set to '0', and a bit reserved for the future.

Thus, in the FEC block header of E in Figure 39, a total of 12348 bytes (12348B) of padding is achieved by the 1 byte (1 byte) EXT byte, the 2 bytes of additional padding length, and the 12345 bytes (12345B) of additional padding.

(Detailed example 2 of Format 1)
40 and 41 show a detailed example 2 of Format 1. In this detailed example 2, as in the above detailed example 1, a configuration is shown in which padding is added to an FEC block header consisting of a base header and EXT bytes.

(3-1-2A): Padding = 1, EXT = 1, TS = 1
FIG. 40A shows the configuration of an FEC block header when the EXT flag = '1' and the TS flag = '1' are specified when the length of padding is 1 byte (1B).

In A of Figure 40, the first TLV packet position pointer and the EXT flag are placed in the base header, but because the EXT flag is specified as '1', the next byte after the base header becomes the EXT byte as an optional header.

In this EXT byte, the first two bits are set to '00' as a padding value, and the following bit is set to '1' as a TS flag. In this case, the packet placed in the FEC block is a TS packet, so the first TLV packet position pointer indicates the position (first position) of the TS packet in the FEC block. In addition, the remaining five bits in the EXT byte are set to bits reserved for the future, along with a CRC flag of '0'.

In this way, in the FEC block header of A in Figure 40, 1 byte (1B) of padding is achieved by using 1 byte (1B) of EXT byte.

(3-1-2B): Padding = 2, EXT = 1, TS = 1
FIG. 40B shows the configuration of the FEC block header when the EXT flag = '1' and the TS flag = '1' are specified when the length of padding is 2 bytes (2B).

In B of Figure 40, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first 2 bits of the padding value are set to '01', so the next byte after the EXT byte is an additional 1B padding.

In the EXT byte, the bit following the first two bits is set to '1' as the TS flag. The remaining five bits of the EXT byte are set to '0' as the CRC flag and a bit reserved for the future.

In this way, in the FEC block header of B in Figure 40, a total of 2 bytes (2B) of padding is achieved by 1 byte (1B) of EXT byte and 1 byte (1B) of additional padding.

(3-1-2C): Padding = 3, EXT = 1, TS = 1
FIG. 40C shows the configuration of the FEC block header when the EXT flag = '1' and the TS flag = '1' are specified when the length of padding is 3 bytes (3B).

In C of Figure 40, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first two bits of the padding value are set to '10', so the next two bytes after the EXT byte indicate the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '0' ('00000000 00000000'), which means that no more padding will be added.

In the EXT byte, the bit following the first two bits is set to '1' as the TS flag. The remaining five bits of the EXT byte are set to '0' as the CRC flag and a bit reserved for the future.

In this way, in the FEC block header of C in Figure 40, a total of 3 bytes (3B) of padding is achieved by the 1 byte (1B) of EXT byte and the 2 bytes (2B) of additional padding.

(3-1-2D): Padding = 4, EXT = 1, TS = 1
FIG. 41D shows the configuration of an FEC block header when the EXT flag is set to '1' and the TS flag is set to '1' when the length of padding is 4 bytes (4B).

In Figure 41D, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first two bits of the padding value are set to '10', so the next two bytes after the EXT byte indicate the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '1' ('00000000 00000001'), so one more byte (1B) of padding is added following the length of the additional padding.

In the EXT byte, the bit following the first two bits is set to '1' as the TS flag. The remaining five bits of the EXT byte are set to '0' as the CRC flag and a bit reserved for the future.

In this way, in the FEC block header of Figure 41D, a total of 4 bytes (4B) of padding is achieved by 1 byte (1B) of EXT byte, 2 bytes (2B) of additional padding length, and 1 byte (1B) of additional padding.

(Detailed Example 3 of Format 1)
42 and 43 show a detailed example 3 of Format 1. This detailed example 3 shows a configuration in which padding is added to an FEC block header consisting of a base header, an EXT byte, and a CRC.

(3-1-3A): Padding = 1, EXT = 1, CRC = 1
FIG. 42A shows the configuration of an FEC block header when the EXT flag = '1' and the CRC flag = '1' are specified when the length of padding is 1 byte (1B).

In A of Figure 42, the first TLV packet position pointer and the EXT flag are placed in the base header, but because the EXT flag is specified as '1', the next byte after the base header becomes the EXT byte as an optional header.

In this EXT byte, the first two bits are set to '00' as a padding value, and the following bit is set to '0' as a TS flag. The following bit is set to '1' as a CRC flag, so a 1-byte (8-bit) CRC is added after the EXT byte.

In this way, in the FEC block header of A in Figure 42, 1 byte (1B) of padding is achieved by using 1 byte (1B) of EXT byte.

(3-1-3B): Padding = 2, EXT = 1, CRC = 1
FIG. 42B shows the configuration of the FEC block header when the EXT flag = '1' and the CRC flag = '1' are specified when the padding length is 2 bytes (2B).

In B of Figure 42, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the padding value of the first two bits is set to '01', and the CRC flag of the following bits is set to '1'.

Therefore, one byte of CRC is added after the EXT byte, and the next byte after this CRC is an additional 1B padding.

In this way, in the FEC block header of B in Figure 42, a total of 2 bytes (2B) of padding is achieved by 1 byte (1B) of EXT byte and 1 byte (1B) of additional padding.

(3-1-3C): Padding = 3, EXT = 1, CRC = 1
FIG. 42C shows the configuration of the FEC block header when the EXT flag = '1' and the CRC flag = '1' are specified when the padding length is 3 bytes (3B).

In C of Figure 42, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first two bits of the padding value are set to '10', and the following bits of the CRC flag are set to '1'. Therefore, a one-byte CRC is added after the EXT byte, and the next two bytes after this CRC indicate the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '0' ('00000000 00000000'), which means that no more padding will be added.

In this way, in the FEC block header of C in Figure 42, a total of 3 bytes (3B) of padding is achieved by the 1 byte (1B) of EXT byte and the 2 bytes (2B) of additional padding.

(3-1-3D): Padding = 4, EXT = 1, CRC = 1
FIG. 43D shows the configuration of the FEC block header when the EXT flag = '1' and the CRC flag = '1' are specified when the padding length is 4 bytes (4B).

In Figure 43D, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the first two bits of the padding value are set to '10', and the following bits of the CRC flag are set to '1'. Therefore, a one-byte CRC is added after the EXT byte, and the next two bytes after this CRC indicate the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '1' ('00000000 00000001'), so an additional byte (1B) of padding is added.

In this way, in the FEC block header of Figure 43D, a total of 4 bytes (4B) of padding is achieved by 1 byte (1B) of EXT byte, 2 bytes (2B) of additional padding length, and 1 byte (1B) of additional padding.

The above describes the configuration of the first format of the FEC block header. In this first format, 15 bits are reserved for the base header of the FEC block header, taking into account the maximum value of the first TLV packet position pointer, so that the maximum number of bits (Num Bits) can accommodate all code lengths, including long codes with a maximum value of 15 bits, middle codes with a maximum value of 13 bits, and short codes with a maximum value of 11 bits. This allows for a very simplified configuration of the FEC block header.

(3-2) Second Format Next, the configuration of the FEC block header (FBH) in the second format (hereinafter also referred to as format 2) will be described with reference to FIGS.

In the second format, we will assume that long codes do not exist in the target standard, and will explain the case where 11 bits corresponding to short codes and 13 bits corresponding to middle codes are reserved as the bits for the first TLV packet position pointer in the base header of the FEC block header.

(FEC block header format)
FIG. 44 is a diagram showing an example of the format of the FEC block header of format 2-1.

In Figure 44, the 2-byte base header consists of an 11-bit first TLV packet position pointer and the remaining bits (5 bits).

The first TLV packet position pointer is a pointer that indicates the position of the first TLV packet in the FEC block that contains the FEC block header in which it is placed. In the base header of format 2-1, 11 bits are reserved for this first TLV packet position pointer, so it can be used as a pointer to the short code.

The remaining 5 bits are allocated to 2 padding bits, 1 TS flag, 1 CRC flag, and 1 reserved bit.

For example, the padding value is specified as shown in FIG. 45. The padding value of this format 2-1 is the same as the padding value of format 1 described above (FIG. 36), so a description of it is omitted here.

The TS flag is a flag that identifies a TS packet. The CRC flag is a flag that indicates whether or not a CRC, which is an error detection code, is present. The reserved area is an area to be used in the future.

(FEC block header format)
FIG. 46 is a diagram showing an example of the format of the FEC block header of format 2-2.

In Figure 46, the 2-byte base header consists of a 13-bit first TLV packet position pointer and the remaining bits (3 bits).

The first TLV packet position pointer is a pointer that indicates the position of the first TLV packet in the FEC block that contains the FEC block header in which it is placed. In the base header of format 2-2, 13 bits are reserved for this first TLV packet position pointer, so it can be used as a pointer to the middle code and short code.

The remaining 3 bits are assigned to 2 padding bits and 1 TS or 1 CRC flag. In other words, the padding value is required in the base header, but it is optional whether to place the TS or CRC flag.

For example, the padding value is specified as shown in FIG. 47. The padding value of this format 2-2 is the same as the padding value of format 1 described above (FIG. 36), so a description of it is omitted here.

The TS flag is a flag that identifies a TS packet. The CRC flag is a flag that indicates whether or not a CRC, which is an error detection code, is present.

The above describes the configuration of the second format of the FEC block header. In this second format, it is assumed that the target standard does not include long codes, and 11 or 13 bits are reserved for the base header of the FEC block header, so that the maximum number of bits (Num Bits) can accommodate short codes with 11 bits or middle codes with 13 bits. Therefore, if the target standard does not include long codes, the configuration of the FEC block header can be very simplified.

(3-3) Third Format Next, the configuration of the FEC block header (FBH) of the third format (hereinafter also referred to as format 3) will be described with reference to FIGS.

(FEC block header format)
FIG. 48 is a diagram showing an example of the format of a Format 3 FEC block header.

In Figure 48, the 2-byte base header consists of a 13-bit first TLV packet position pointer and the remaining bits (3 bits).

The first TLV packet position pointer is a pointer that indicates the position of the first TLV packet in the FEC block that contains the FEC block header in which it is placed. In the base header of format 3, 13 bits are reserved for this first TLV packet position pointer.

The remaining 3 bits are assigned to 1 TS flag, 1 CRC flag, and 1 EXT flag. Details of the TS flag and CRC flag are as described above.

The EXT flag indicates whether an extension area exists. For example, if the EXT flag is set to '1', the next byte after the base header is the EXT byte.

Figure 49 shows an example of the EXT byte format. In Figure 49, one EXT byte consists of a 2-bit LEN_MSB, a 2-bit padding value, and a 4-bit reserved area.

In the case of long codes, the maximum value of the first TLV packet position pointer is 15 bits, which is insufficient from the 13 bits allocated to the base header, so the 2 bits of LEN_MSB are used to make up for the shortfall. Note that in the case of short codes and middle codes, the 13 bits allocated to the base header are sufficient, so the 2 bits of LEN_MSB are unused.

In other words, in the case of short codes and middle codes, the 13 bits allocated to the base header can be used to accommodate the maximum value of the first TLV packet position pointer (11 bits or 13 bits). On the other hand, in the case of long codes, the 13 bits allocated to the base header are insufficient, so an additional 2 bits are used in the LEN_MSB to accommodate a total of 15 bits to accommodate the maximum value of the first TLV packet position pointer (15 bits).

For example, the padding value is specified as a value according to the contents shown in FIG. 50. The padding value of this format 3 is the same as the padding value of format 1 described above (FIG. 36), so a description of it will be omitted here. The reserved area is an area to be used in the future.

(FEC block header format)
FIG. 51 is a diagram showing an example of the format of an FEC block header of format 3-1.

In Figure 51, the 2-byte base header consists of a 13-bit first TLV packet position pointer and the remaining bits (3 bits).

Format 3-1 is the same as format 3 described above in that the number of bits in the first TLV packet position pointer is 13 bits, but it differs in that the remaining 3 bits are assigned to a 2-bit padding value and a 1-bit EXT flag.

For example, the padding value is specified as shown in FIG. 52. The padding value of this format 3-1 is the same as the padding value of format 1 described above (FIG. 36), so a description of it is omitted here.

The EXT flag indicates whether an extension area exists. For example, if the EXT flag is set to '1', the next byte after the base header is the EXT byte.

Figure 53 shows an example of the format of an EXT byte. In Figure 53, one EXT byte consists of a 2-bit LEN_MSB, a 1-bit TS flag, a 1-bit CRC flag, and a 4-bit reserved area.

In the case of long codes, the maximum value of the first TLV packet position pointer is 15 bits, which is insufficient from the 13 bits allocated to the base header, so the 2 bits of LEN_MSB are used to make up for the shortfall. In the case of short codes and middle codes, the 2 bits of LEN_MSB are unused.

In other words, in the case of short codes and middle codes, the 13 bits allocated to the base header can be used to accommodate the maximum value of the first TLV packet position pointer (11 bits or 13 bits). On the other hand, in the case of long codes, the 13 bits of the base header and the 2 bits of LEN_MSB make up a total of 15 bits that can accommodate the maximum value of the first TLV packet position pointer (15 bits).

Details about the TS flag and CRC flag are as described above. The reserved area is an area to be used in the future.

Next, a more specific detailed example of Format 3-1 will be described. Note that in the following explanation, as with the detailed example of Format 1 described above, the FEC block and TLV packet will be omitted and only the FEC block header will be illustrated.

(Detailed example 1 of Format 3-1)
54 to 56 show a detailed example 1 of Format 3-1. This detailed example 1 shows a configuration in which padding is added to an FEC block header consisting of a base header.

(3-3-1A): No Padding, EXT = 0
FIG. 54A shows the configuration of the FEC block header when there is no padding and the EXT flag is set to '0'.

In A of Figure 54, in addition to the 13-bit first TLV packet position pointer, the base header contains a 2-bit padding value and a 1-bit EXT flag, but since the padding value is specified as '00', there is no additional padding. Furthermore, since the EXT flag is specified as '0', there is no extension of the EXT byte as an optional header.

In this way, the FEC block header in A of Figure 54 is configured when no padding is performed.

(3-3-1B):Padding = 1, EXT = 0
FIG. 54B shows the configuration of the FEC block header when the EXT flag = '0' is specified when the length of padding is 1 byte (1B).

In B of Figure 54, the padding value is specified as '01', so the next byte after the base header is an additional 1B of padding. Note that the EXT flag is specified as '0', so there is no extension of the EXT byte.

In this way, in the FEC block header of B in Figure 54, 1 byte (1B) of padding is achieved by adding 1 byte (1B).

(3-3-1C):Padding = 2, EXT = 0
FIG. 54C shows the configuration of the FEC block header when the EXT flag = '0' is specified when the length of padding is 2 bytes (2B).

In C of Figure 54, the padding value is specified as '10', so the next two bytes after the base header indicate the length of the additional padding. Here, the length of the two bytes of additional padding is specified as '0' ('00000000 00000000'), which indicates that no more padding will be added.

Note that the EXT flag is set to '0', so there is no extension of the EXT byte.

In this way, in the FEC block header of C in Figure 54, 2 bytes (2B) of padding is achieved by the length of the additional padding of 2 bytes (2B).

(3-3-1D): Padding = 3, EXT = 0
FIG. 55D shows the configuration of the FEC block header when the EXT flag = '0' is specified when the length of padding is 3 bytes (3B).

In Figure 55D, the padding value is specified as '10', so the next two bytes after the base header indicate the length of the additional padding. Here, the length of the two bytes of additional padding is specified as '1' ('00000000 00000001'), so one more byte (1B) of padding is added following the length of the additional padding.

Note that the EXT flag is set to '0', so there is no extension of the EXT byte.

In this way, in the FEC block header of Figure 55D, a total of 3 bytes (3B) of padding is achieved by adding 2 bytes (2B) of additional padding and 1 byte (1B) of additional padding.

(3-3-1E): Padding = 4, EXT = 0
FIG. 55E shows the configuration of the FEC block header when the EXT flag = '0' is specified when the length of padding is 4 bytes (4B).

In Figure 55E, the padding value is specified as '10', so the next two bytes after the base header indicate the length of the additional padding. Here, the length of the two bytes of additional padding is specified as '2' ('00000000 00000010'), so two bytes (2B) of padding are added following the length of the additional padding.

Note that the EXT flag is set to '0', so there is no extension of the EXT byte.

In this way, in the FEC block E of Figure 55, a total of 4 bytes (4B) of padding is achieved by adding 2 bytes (2B) of additional padding and 2 bytes (2B) of additional padding.

(3-3-1F):Padding = 12348, EXT = 0
FIG. 56F shows the configuration of the FEC block header when the EXT flag = '1' is specified when the length of the padding is 12348 bytes (12348B).

In F of Figure 56, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In addition, the padding value is set to '10', so the next two bytes after the EXT byte indicate the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '12345' ('00110000 00111001'), so an additional 12345 bytes (12345B) of padding is added.

In addition, by using the 2-bit LEN_MSB in the EXT byte, the first TLV packet position pointer can be used to support not only short codes and middle codes, but also long codes.

In this way, in the FEC block header of Figure 56F, a total of 12348 bytes (12348B) of padding is achieved by the 1 byte (1B) EXT byte, 2 bytes (2B) of additional padding length, and 12345 bytes (12345B) of additional padding.

(Detailed example 2 of Format 3-1)
57 and 58 show a detailed example 2 of Format 3-1. This detailed example 2 shows a configuration in which padding is added to an FEC block header consisting of a base header and an EXT byte.

(3-3-2A): Padding = 1, EXT = 1, TS = 1
FIG. 57A shows the configuration of the FEC block header when the EXT flag = '1' is specified when the length of padding is 1 byte (1B).

In A of Figure 57, in addition to the 13-bit first TLV packet position pointer, the base header also contains a 2-bit padding value and a 1-bit EXT flag. However, since the padding value is specified as '00', no additional padding is added. On the other hand, since the EXT flag is specified as '1', the next byte after the base header is the EXT byte as an optional header.

In the EXT byte, the TS flag is set to '1', and the packet placed in the FEC block is a TS packet, so the first TLV packet position pointer indicates the position (first position) of the TS packet in the FEC block.

In this way, in the FEC block header of A in Figure 57, 1 byte (1B) of padding is achieved by using 1 byte (1B) of EXT byte.

(3-3-2B): Padding = 2, EXT = 1, TS = 1
FIG. 57B shows the configuration of the FEC block header when the EXT flag = '1' is specified when the length of padding is 2 bytes (2B).

In B of Figure 57, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. Also, the padding value is set to '01', so the next byte after the EXT byte is an additional 1B padding.

In this way, in the FEC block header of B in Figure 57, a total of 2 bytes (2B) of padding is achieved by 1 byte (1B) of EXT byte and 1 byte (1B) of additional padding.

(3-3-2C): Padding = 3, EXT = 1, TS = 1
FIG. 57C shows the configuration of the FEC block header when the EXT flag = '1' is specified when the padding length is 3 bytes (3B).

In C of Figure 57, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In addition, the padding value is set to '10', so the next byte after the EXT byte indicates the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '0' ('00000000 00000000'), which means that no more padding will be added.

In this way, in the FEC block header of C in Figure 57, a total of 3 bytes (3B) of padding is achieved by the 1 byte (1B) of EXT byte and the 2 bytes (2B) of additional padding.

(3-3-2D): Padding = 4, EXT = 1, TS = 1
FIG. 58D shows the configuration of the FEC block header when the EXT flag = '1' is specified when the padding length is 4 bytes (4B).

In Figure 58D, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In addition, the padding value is set to '10', so the next byte after the EXT byte indicates the length of the additional padding.

Here, the length of the 2 bytes of additional padding is specified as '1' ('00000000 00000001'), so one more byte (1B) of padding is added following the length of the additional padding.

In this way, in the FEC block header of Figure 58D, a total of 4 bytes (4B) of padding is achieved by 1 byte (1B) of EXT byte, 2 bytes (2B) of additional padding length, and 1 byte (1B) of additional padding.

(Detailed example 3 of Format 3-1)
59 and 60 show a detailed example 3 of Format 3-1. This detailed example 3 shows a configuration in which padding is added to an FEC block header consisting of a base header, an EXT byte, and a CRC.

(3-3-3A): Padding = 1, EXT = 1, CRC = 1
FIG. 59A shows the configuration of the FEC block header when the EXT flag = '1' and the CRC flag = '1' are specified when the padding length is 1 byte (1B).

In A of Figure 59, in addition to the 13-bit first TLV packet position pointer, the base header also contains a 2-bit padding value and a 1-bit EXT flag. However, since the padding value is specified as '00', no additional padding is added. On the other hand, since the EXT flag is specified as '1', the next byte after the base header is the EXT byte, which serves as an optional header.

In this EXT byte, the 4th bit is set to '1' as the CRC flag, so one byte (8 bits) of CRC is added after the EXT byte.

In this way, in the FEC block header of A in Figure 59, 1 byte (1B) of padding is achieved by using 1 byte (1B) of EXT byte.

(3-3-3B): Padding = 2, EXT = 1, CRC = 1
FIG. 59B shows the configuration of the FEC block header when the EXT flag = '1' and the CRC flag = '1' are specified when the padding length is 2 bytes (2B).

In B of Figure 59, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the 4th bit is set to '1' as the CRC flag, so one byte (8 bits) of CRC is added after the EXT byte.

Also, in the base header, the padding value is specified as '01', so the byte following the CRC is an additional 1B padding.

In this way, in the FEC block header of B in Figure 59, a total of 2 bytes (2B) of padding is achieved by 1 byte (1B) of EXT byte and 1 byte (1B) of additional padding.

(3-3-3C): Padding = 3, EXT = 1, CRC = 1
FIG. 59C shows the configuration of the FEC block header when the EXT flag = '1' and the CRC flag = '1' are specified when the padding length is 3 bytes (3B).

In Figure 59C, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the 4th bit is set to '1' as the CRC flag, so one byte (8 bits) of CRC is added after the EXT byte.

In addition, in the base header, the padding value is specified as '10', so the two bytes following the CRC indicate the length of the additional padding. Here, the length of the two bytes of additional padding is specified as '0' ('00000000 00000000'), which indicates that no more padding will be added.

In this way, in the FEC block header of C in Figure 59, a total of 3 bytes (3B) of padding is achieved by the 1 byte (1B) of EXT byte and the 2 bytes (2B) of additional padding.

(3-3-3D): Padding = 4, EXT = 1, CRC = 1
FIG. 60D shows the configuration of the FEC block header when the EXT flag = '1' and the CRC flag = '1' are specified when the padding length is 4 bytes (4B).

In Figure 60D, the EXT flag is set to '1', so the next byte after the base header is the EXT byte. In this EXT byte, the 4th bit is set to '1' as the CRC flag, so one byte (8 bits) of CRC is added after the EXT byte.

In addition, in the base header, the padding value is specified as '10', so the two bytes following the CRC indicate the length of the additional padding. Here, the length of the two bytes of additional padding is specified as '1' ('00000000 00000001'), so one byte (1B) of padding is added.

In this way, in the FEC block header of Figure 60D, a total of 4 bytes (4B) of padding is achieved by 1 byte (1B) of EXT byte, 2 bytes (2B) of additional padding length, and 1 byte (1B) of additional padding.

The above describes the configuration of the third format of the FEC block header. In this third format, when a long code is included in the target standard, 13 bits are reserved in the base header of the FEC block header to accommodate a short code with a maximum number of bits (Num Bits) of 11 bits or a middle code with a maximum number of bits (Num Bits) of 13 bits, and when a long code has a maximum number of bits (Num Bits) of 15 bits, the two bits of the LEN_MSB of the EXT byte are used to accommodate the long code with a maximum number of bits (Num Bits) of 15 bits. Therefore, when a long code is included in the standard, there is no need to use the LEN_MSB of the EXT byte in the case of a middle code or a short code, and the FEC block header can be efficiently configured.

(3-4) Fourth Format Finally, with reference to Figures 61 to 63, the configuration of the FEC block header (FBH) of the fourth format (hereinafter also referred to as format 4) will be described.

(FEC block header format)
FIG. 61 is a diagram showing an example of the format of a Format 4 FEC block header.

In Figure 61, the 2-byte base header consists of a 13-bit first TLV packet position pointer, a 1-bit TS flag, a 1-bit CRC flag, and a 1-bit EXT flag.

The first TLV packet position pointer is a pointer that indicates the position of the first TLV packet in the FEC block that contains the FEC block header in which it is placed.

The remaining 3 bits are assigned to 1 TS flag, 1 CRC flag, and 1 EXT flag. Details of the TS flag and CRC flag are as described above.

The EXT flag indicates whether an extension area exists. For example, if the EXT flag is set to '1', the next byte after the base header is the EXT byte.

Figure 62 shows an example of the format of an EXT byte. In Figure 62, one EXT byte consists of a 5-bit LEN_MSB, a 2-bit padding value, and a 1-bit reserved area.

In the above-mentioned Figures 31 to 33, the number of bits (Num Bits) is the number of bits required according to K_bch (B: bytes), but when K_bch (bits) is used, the number of bits (Num Bits) is as follows.

In other words, in the case of a middle code with a code length of 69120 bits, when the maximum coding rate is CR = 14/16, the number of bits (Num Bits) is 16 bits, so the maximum value of the first TLV packet position pointer is 16 bits.

In addition, in the case of a long code with a code length of 276480 bits, when the maximum coding rate is CR = 14/16, the number of bits (Num Bits) is 18 bits, so the maximum value of the first TLV packet position pointer is 18 bits.

In addition, in the case of a short code with a code length of 17280 bits, when the maximum coding rate is CR = 14/16, the number of bits (Num Bits) is 14 bits, so the maximum value of the first TLV packet position pointer is 14 bits.

As described above, when using bit representation (K_bch (B:byte)) as the number of bits (Num Bits) instead of byte representation (K_bch (B:byte)), the maximum value of the first TLV packet position pointer is 18 bits, 16 bits, and 14 bits for the long code, middle code, and short code, respectively. Therefore, since the 13 bits allocated to the first TLV packet position pointer in the base header are insufficient, the 5 bits of LEN_MSB are used to make up the shortfall.

In other words, a total of 18 bits, consisting of the 13 bits allocated to the base header and the 5 bits of LEN_MSB, are used as the first TLV packet position pointer. By allocating bits in this way, the first TLV packet position pointer can be expressed in bits.

Specifically, in the case of a long code, all five bits of LEN_MSB are used, making a total of 18 bits available as bits for the first TLV packet position pointer. In the case of a medium code, three of the five bits of LEN_MSB are used, making a total of 16 bits available. In the case of a short code, one of the five bits of LEN_MSB is used, making a total of 14 bits available.

In other words, in the case of byte representation, the 13 bits allocated to the base header are insufficient for all long codes, middle codes, and short codes, so the 5 bits of LEN_MSB are used to accommodate the maximum value of the first TLV packet position pointer (18 bits, 16 bits, or 14 bits).

For example, the padding value is specified as a value according to the contents shown in FIG. 63. The padding value of this format 4 is the same as the padding value of format 1 described above (FIG. 36), so a description of it is omitted here. The reserved area is an area to be used in the future.

The above describes the configuration of the fourth format of the FEC block header. In this fourth format, when a long code exists in the target standard, 18 bits are reserved by the base header (13 bits) of the FEC block header and the LEN_MSB (5 bits) of the EXT byte, making it possible to accommodate a short code with a maximum number of bits (Num Bits) of 14 bits, a middle code with a maximum number of bits (Num Bits) of 16 bits, and a long code with a maximum number of bits (Num Bits) of 18 bits. Therefore, when a long code exists in the standard, the first TLV packet position pointer can be expressed in bits.

＜4. Timing of sending time information with this technology＞

The current ISDB-T standard uses frequency division multiplexing (FDM) as the method for multiplexing broadcast signals. It is expected that the next generation of terrestrial digital television broadcasting will also use frequency division multiplexing (FDM).

When this frequency division multiplexing method (FDM) is adopted, a given frequency band (e.g., 6 MHz) is divided into multiple segments, and hierarchical transmission is performed using the bandwidth of one or more segments. In this case, for example, data for different services can be transmitted for each hierarchy consisting of the frequency band of one or more segments obtained by frequency division.

That is, each layer is a unit that groups together one or more segments. In ISDB-T, OFDM segments are used. Here, in OFDM (Orthogonal Frequency Division Multiplexing), a large number of orthogonal subcarriers are provided within the transmission band, and digital modulation is performed. Note that the layer (FDM layer) can also be conceptually considered as a PLP (Physical Layer Pipe). In this case, multiple layers can also be said to be M-PLP (Multiple-PLP).

In addition, in terrestrial digital television broadcasting, time information is transmitted to synchronize the transmitting side and the receiving side, and synchronization is achieved between the transmitting device 20 on the transmitting side and the receiving device 30 on the receiving side.

Figure 64 shows an example of the timing of sending time information.

In FIG. 64, the data processed by the transmitting device 20 is shown diagrammatically at the top, and the data processed by the receiving device 30 is shown diagrammatically at the bottom. In addition, in FIG. 64, the horizontal direction represents time, which runs from the left to the right in the figure.

First, we will explain the data processed by the transmitting device 20.

The transmitting device 20 performs the necessary processing on the TLV packet to obtain an FEC frame including an FEC block to which a BCH code and an LDPC code are added. The transmitting device 20 also performs the necessary processing on the FEC frame to obtain a physical layer frame (hereinafter, referred to as an ISDB-T2 frame).

The TLV packet is a variable-length packet, and can be, for example, 4 to 65,536 bytes in size. The TLV packet is represented as "Data" in the diagram. Also, the NTP time information, which is time information in NTP (Network Time Protocol) format, is represented as "NTP" in the diagram.

The FEC frame includes an FEC block to which a BCH code and an LDPC code are added. One ISDB-T2 frame is composed of k+1 FEC frames, FEC frame #0 to FEC frame #k. An FEC block header (FBH) is added to the beginning of each FEC frame, and if padding is inserted, a certain number of additional bytes of padding are inserted following the FEC block header (FBH).

As described above, the FEC block header (FBH) includes a first TLV packet position pointer. For example, if we look at Data#1 as a TLV packet, Data#1-1 and Data#1-2 are arranged across FEC frame #0 and FEC frame #1. The first TLV packet position pointer included in the FEC block header (FBH) added to the beginning of FEC frame #1 indicates the beginning of Data#2, which is arranged following Data#1-2 in that FEC frame #1.

The OFDM symbol is represented by "Symbol" in the figure. One ISDB-T2 frame is composed of n+1 OFDM symbols, Symbol#0 through Symbol#n. In other words, this ISDB-T2 frame can be said to be the OFDM frame that is the unit for transmitting data.

However, when frequency division multiplexing (FDM) is used as the method for multiplexing broadcast signals, the OFDM symbol is further divided into segments. A segment is represented by "Seg" in the diagram. One OFDM symbol is made up of m+1 segments, Seg#0 through Seg#m.

In this technology, the NTP time information is inserted so that it is at the beginning of the ISDB-T2 frame (strictly speaking, the NTP time information is inserted following the FEC block header (FBH) added to the first FEC frame #0). This NTP time information includes the time at the beginning of the ISDB-T2 frame as time information specified by NTP.

However, when one ISDB-T2 frame is composed of k+1 FEC frames, the NTP time information is not necessarily placed at the beginning of the ISDB-T2 frame. In such a case, by inserting a dummy cell D following the last FEC frame #k that composes a certain ISDB-T2 frame, it is possible to insert the NTP time information at the beginning of the next ISDB-T2 frame (the beginning of FEC frame #0).

That is, in order to place the NTP time information at the beginning of the ISDB-T2 frame as an OFDM frame, in the transmitting device 20, a dummy cell D is generated by the dummy cell generating unit 161 as necessary and placed in the OFDM frame in which the FEC frame is placed. This links the NTP time information to the frame length of the ISDB-T2 frame as an OFDM frame.

Thus, looking at frame A in Figure 64, the transmitting device 20 inserts NTP time information indicating the time of the start of the ISDB-T2 frame at the beginning of the ISDB-T2 frame, but the boundaries between the ISDB-T2 frame and the FEC frame may or may not match. If these boundaries do not match, the insertion position of the NTP time information will be shifted from the start of the ISDB-T2 frame, so dummy cell D is inserted so that the NTP time information is inserted at the start of the ISDB-T2 frame.

Next, we will explain the data processed by the receiving device 30.

The receiving device 30 performs the necessary processing on the ISDB-T2 frame to obtain a TLV packet. Here, from one ISDB-T2 frame, multiple TLV packets are obtained along with the NTP time information placed at the beginning of the frame. This NTP time information indicates the time at the beginning of the ISDB-T2 frame.

Then, since the boundaries between the ISDB-T2 frame and the TLV packet match, the receiving device 30 can perform clock recovery by referring to the time at the beginning of the ISDB-T2 frame indicated by the NTP time information inserted at the beginning of the ISDB-T2 frame.

This allows clock synchronization using NTP time information to be achieved between the transmitting device 20 on the sending side and the receiving device 30 on the receiving side, and the receiving device 30 is able to process multiple TLV packets (Data#0 to Data#z) for each NTP time information included at the beginning of the ISDB-T2 frame.

As described above, by including NTP time information indicating the time at the beginning of an ISDB-T2 frame, the transmission of time information is performed with high accuracy and efficiency, and the receiving device 30 can use the NTP time information to perform clock synchronization (clock recovery).

＜5. Operation of the sender and receiver＞

Next, the operation of the transmitting device 20 on the transmitting side and the receiving device 30 on the receiving side will be described with reference to the flowchart in FIG. 65.

The processes of steps S11 to S13 in FIG. 65 are performed, for example, by the data processing unit 211 and the modulation unit 212 of the transmitting device 20 (FIG. 2). The processes of steps S31 to S33 in FIG. 65 are performed, for example, by the demodulation unit 312 and the data processing unit 313 of the receiving device 30 (FIG. 3).

In step S11, the FEC block generator 153 processes the TLV packet input thereto to generate an FEC block. An FEC block header (FBH) including a TLV packet position pointer, a TS flag, and a CRC flag is inserted at the beginning of this FEC block.

In step S12, the FEC frame generation unit 154 processes the FEC block generated in step S11 and generates an FEC frame.

In step S13, the modulation unit 212 processes the FEC frame generated in the processing of step S12 and transmits a signal obtained from the FEC frame. In this way, the signal transmitted from the transmitting device 20 on the transmitting side is received by the receiving device 30 on the receiving side.

In step S31, the tuner 311 receives a signal obtained from the FEC frame.

In step S32, the demodulation unit 312 processes the signal received in the processing of step S31 and generates an FEC block.

In step S33, the data processing unit 313 processes the FEC block generated in step S32 to generate a TLV packet. An FEC block header (FBH) including a TLV packet position pointer, a TS flag, and a CRC flag is inserted at the beginning of this FEC block.

Here, this TLV packet position pointer can be used to reliably identify the position of the first TLV packet in the FEC block, and the TLV packet can be extracted from that FEC block. The TLV packet obtained in this way is further processed by the receiving device 30 (the data processing unit 313 or a subsequent processing unit) on the receiving side, and the content of the broadcast program or the like is reproduced.

The above explains the operation of the sending and receiving sides.

＜6. Modifications＞

(Application to other broadcasting systems)
In the above explanation, the description has focused on ISDB (Integrated Services Digital Broadcasting), a standard for digital television broadcasting that is adopted in Japan and other countries. However, the present technology may also be applied to ATSC (Advanced Television Systems Committee), a standard adopted in the United States and other countries, or DVB (Digital Video Broadcasting), a standard adopted in European countries and other countries.

In addition to terrestrial broadcasting, the digital television broadcasting standard can also be applied to satellite broadcasting using broadcast satellites (BS) and communication satellites (CS), and wired broadcasting such as cable television (CATV).

(Other examples of packets and signaling)
In addition, the names of the above-mentioned packets, frames, signaling (control information), etc. are merely examples, and other names may be used. However, the difference between these names is merely a formal difference, and does not mean that the actual contents of the target packets, frames, signaling, etc. are different.

For example, a TLV packet is an example of a transmission packet, and transmission packets include, for example, variable-length packets such as ALP (ATSC Link-Layer Protocol) packets and GSE (Generic Stream Encapsulation) packets. Note that the terms frame and packet are sometimes used interchangeably.

(Other examples of time information)
In the above explanation, the case where time information defined by NTP is used as the time information has been described, but the present invention is not limited to this and any time information can be used, such as time information defined by PTP (Precision Time Protocol) or 3GPP (Third Generation Partnership Project), time information included in GPS (Global Positioning System) information, or time information in any other independently determined format.

(Another example of a transmission line)
In addition, the present technology can also be applied to a transmission path other than a broadcasting network, i.e., a predetermined standard (a standard other than a digital broadcasting standard) that is defined assuming the use of a communication line (communication network) such as the Internet or a telephone network as a transmission path. In that case, a communication line such as the Internet is used as the transmission path of the transmission system 1 (FIG. 1), and the functions of the data processing device 10 and the transmitting device 20 are provided by a communication server provided on the Internet. Then, the communication server and the receiving device 30 communicate bidirectionally via the communication line.

＜7. Computer configuration＞

The above-mentioned series of processes can be executed by hardware or software. When the series of processes is executed by software, a program constituting the software is installed on a computer. Figure 66 shows an example of the hardware configuration of a computer that executes the above-mentioned series of processes by a program.

In the computer 1000, a CPU (Central Processing Unit) 1001, a ROM (Read Only Memory) 1002, and a RAM (Random Access Memory) 1003 are interconnected by a bus 1004. An input/output interface 1005 is further connected to the bus 1004. An input unit 1006, an output unit 1007, a recording unit 1008, a communication unit 1009, and a drive 1010 are connected to the input/output interface 1005.

The input unit 1006 includes a keyboard, a mouse, a microphone, etc. The output unit 1007 includes a display, a speaker, etc. The recording unit 1008 includes a hard disk, a non-volatile memory, etc. The communication unit 1009 includes a network interface, etc. The drive 1010 drives a removable recording medium 1011 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory.

In the computer 1000 configured as described above, the CPU 1001 loads the programs recorded in the ROM 1002 or the recording unit 1008 into the RAM 1003 via the input/output interface 1005 and the bus 1004, and executes them, thereby performing the above-mentioned series of processes.

The program executed by the computer 1000 (CPU 1001) can be provided by being recorded on a removable recording medium 1011 such as a package medium, for example. The program can also be provided via a wired or wireless transmission medium such as a local area network, the Internet, or digital satellite broadcasting.

In the computer 1000, the program can be installed in the recording unit 1008 via the input/output interface 1005 by inserting the removable recording medium 1011 into the drive 1010. The program can also be received by the communication unit 1009 via a wired or wireless transmission medium and installed in the recording unit 1008. Alternatively, the program can be pre-installed in the ROM 1002 or the recording unit 1008.

In this specification, the processing performed by a computer according to a program does not necessarily have to be performed chronologically in the order described in the flowchart. In other words, the processing performed by a computer according to a program also includes processing executed in parallel or individually (for example, parallel processing or processing by objects). In addition, a program may be processed by one computer (processor), or may be processed in a distributed manner by multiple computers.

The embodiment of this technology is not limited to the above-mentioned embodiment, and various modifications are possible without departing from the spirit of this technology.

Furthermore, the effects described in this specification are merely examples and are not limiting, and other effects may also be present.

Furthermore, this technology can be configured as follows:

(1)
A first generator for generating a forward error correction (FEC) block based on an input packet or an input stream;
a second generating unit for generating an FEC frame based on the FEC block;
a transmitter for transmitting the FEC frame;
A transmitting device, wherein the header of the FEC block includes a minimum fixed-length header having type identification information that identifies the type of the input packet or the input stream, information for detecting a header error, and position information of the beginning of the input packet or the input stream to be stored in the payload of the FEC frame.
(2)
When the type identification information is a TLV (Type Length Value) packet, the minimum fixed length header includes, in addition to the type identification information, minimum fixed length identification information that identifies whether the input packet length of the input packet is a minimum fixed length, and a minimum input packet length as information on the input packet length.The transmitting device described in (1).
(3)
if the minimum fixed length identification information indicates that the input packet length is not the minimum fixed length, the header further includes a variable length header in addition to the minimum fixed length header;
The transmitting device described in (2), wherein the variable-length header includes variable-length packet length information consisting of the upper bits of the input packet length when the lower bits of the input packet length are minimum input packet length information representing the minimum input packet length.
(4)
The transmitting device according to any one of (1) to (3), further comprising a third generating unit configured to generate a dummy cell for placing time information at the beginning of an OFDM (Orthogonal Frequency Division Multiplexing) frame in which the FEC frame is placed.
(5)
generating an FEC block based on the input packets or input stream;
generating an FEC frame based on the FEC block;
transmitting the FEC frame;
A transmission method, wherein the header of the FEC block includes a minimum fixed-length header having type identification information that identifies the type of the input packet or the input stream, information for detecting a header error, and position information of the beginning of the input packet or the packet of the input stream that is stored in the payload of the FEC frame.
(6)
a receiving unit for receiving a signal consisting of an FEC frame;
a first generating unit for generating an FEC block based on the received FEC frame;
a second generator for generating an input packet or an input stream based on the FEC block;
A receiving device, wherein the header of the FEC block includes a minimum fixed-length header having type identification information that identifies the type of the input packet or the input stream, and position information of the beginning of the input packet or the input stream that is stored in the payload of the FEC frame.
(7)
When the type identification information is a TLV packet, the minimum fixed length header includes, in addition to the type identification information, minimum fixed length identification information that identifies whether the input packet length of the input packet is a minimum fixed length, and a minimum input packet length as information on the input packet length.The receiving device described in (6).
(8)
if the minimum fixed length identification information indicates that the input packet length is not the minimum fixed length, the header further includes a variable length header in addition to the minimum fixed length header;
The variable-length header includes variable-length packet length information consisting of upper bits of the input packet length when the lower bits of the input packet length are minimum input packet length information representing the minimum input packet length. The receiving device (9) described in (7)
The receiving device according to any one of (6) to (8), wherein a dummy cell is inserted into an OFDM frame in which the FEC frame is placed, to place time information at the beginning of the frame.
(10)
receiving an incoming signal consisting of FEC frames;
generating an FEC block based on the received FEC frame;
generating an input packet or an input stream based on the FEC block;
A receiving method, wherein the header of the FEC block includes type identification information that identifies the type of the input packet or the input stream, and a minimum fixed-length header having position information of the beginning of the input packet or the input stream that is stored in the payload of the FEC frame.

1 Transmission system, 10, 10-1 to 10-N Data processing device, 20 Transmission device, 30, 30-1 to 30-M Reception device, 40, 40-1 to 40-N Communication line, 50 Broadcast transmission path, 111 Component processing unit, 112 Signaling generation unit, 113 Multiplexer, 114 Data processing unit, 151 TLV packet generation unit, 152 TS packet processing unit, 153 FEC block generation unit, 154 FEC frame generation unit, 161 Dummy cell generation unit, 211 Data processing unit, 212 Modulation unit, 311 Tuner, 312 Demodulation unit, 313 Data processing unit

Claims (4)

A first generator for generating a forward error correction (FEC) block based on an input packet or an input stream;
a second generating unit for generating an FEC frame based on the FEC block;
a transmitter for transmitting a physical layer frame including the FEC frame;
The FEC block header comprises:
position information of the beginning of the input packet or the input stream stored in a payload of the FEC frame;
padding information indicating at least the addition of a padding of a predetermined fixed length or the addition of a padding of a predetermined length;
type identification information for identifying the type of the input packet or the input stream, or error detection information regarding header error detection ;
Including,
A transmitting device which assigns, to the leading position information, upper bits corresponding to a maximum value of the leading position information determined according to a baseband frame size of a code excluding a long code having the longest code length among the bit strings of the base header of the FEC block, and assigns the remaining bits to the padding information and the type identification information or the error detection information. 2. The transmitting device according to claim 1 , wherein the physical layer frame is a physical layer frame conforming to a next-generation ISDB-T standard . The transmitting device according to claim 1 , wherein a dummy cell is inserted in the physical layer frame , so that time information is placed at the beginning of the frame. generating an FEC block based on the input packets or input stream;
generating an FEC frame based on the FEC block;
transmitting a physical layer frame including the FEC frame;
The FEC block header comprises:
position information of the beginning of the input packet or the input stream stored in a payload of the FEC frame;
padding information indicating at least the addition of a padding of a predetermined fixed length or the addition of a padding of a predetermined length;
type identification information for identifying the type of the input packet or the input stream, or error detection information regarding header error detection ;
Including,
a transmission method in which upper bits corresponding to a maximum value of the first position information determined according to a baseband frame size of a code excluding a long code having the longest code length among the bit strings of the base header of the FEC block are assigned to the first position information, and the remaining bits are assigned to the padding information and the type identification information or the error detection information.

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