CN101370132A - Digital broadcast receiver and method of processing streams of digital broadcast receiver - Google Patents

Abstract

A method of formatting a digital broadcast transport stream packet, a digital broadcast transmitter and a signal processing method thereof, comprising: constructing a transport stream packet including a padding area for inserting known Supplementary Reference Sequence (SRS) data therein; Randomize the packet including the padding area; insert the SRS data into the padding area of the randomized packet. A parity for error correction is added to the packet in which the SRS data is inserted; the parity-added packet is interleaved; trellis encoding is performed on the interleaved packet. A segment sync signal and a field sync signal are inserted into trellis-coded packets, and vestigial sideband (VSB) modulation and RF conversion are performed on the packets to transmit the VSB modulated and RF converted packets.

Description

Digital broadcast receiver and method of processing streams of digital broadcast receiver

This application is a divisional case of a patent application with an application date of May 19, 2006 and an application number of 200680017764.5, entitled "Method for Formatting Digital Broadcasting Transport Stream Packets to Improve Receiving Performance, Digital Broadcasting Transmitter and Signal Processing Method" Apply.

technical field

Aspects of the present invention relate to a method of formatting a digital broadcasting transport stream packet, a digital broadcasting transmitter and a signal processing method thereof, and more particularly, to a method capable of generating an adaptive field in a transport stream packet, and Formatted digital broadcast transport stream packets that insert known data (i.e., Supplementary Reference Sequence (hereinafter referred to as "SRS")) into the position of the adaptation field to improve the reception performance of the receiving system and maintain compatibility with existing systems Method, digital broadcast transmitter and signal processing method thereof.

Background technique

The Advanced Television Systems Committee (ATSC) Vestigial Sideband (VSB) system (American digital terrestrial broadcasting system) is a signal carrier type broadcasting system, and uses a field synchronization signal in units of 312 segments. FIG. 1 is a block diagram showing the configuration of a transmitter/receiver of the ATSC DTV standard, which is a general American type digital terrestrial broadcasting system. The digital broadcast transmitter of Fig. 1 comprises: randomizer 110, is used for moving picture experts group 2 (MPEG-2) transport stream (TS) randomization; Reed-Solomon (RS) encoder 120, is used for RS parity A parity byte is added to the Transport Stream (TS) to correct bit errors in the transport process due to channel characteristics. The interleaver 130 interleaves RS encoded data according to a specified pattern. The trellis encoder 140 maps the interleaved data to 8-level symbols by performing trellis encoding on the interleaved data at a code rate of 2/3. Digital broadcast transmitters perform error correction encoding on the MPEG-2 transport stream.

The digital broadcast transmitter also includes a multiplexer 150 to insert a segment sync signal and a field sync signal into error correction encoded data. The modulator/RF converter 160 inserts a pilot tone into the data symbols by inserting a specified DC value into the data symbols into which the segment and field sync signals have been inserted, and the data symbols are pulse-shaped by pulse-shaping the data symbols. VSB modulation is performed, and the modulated data symbols are up-converted to an RF channel band signal to transmit the RF channel band signal.

Accordingly, the digital broadcast transmitter randomizes the MPEG-2 transport stream, outer-codes the randomized data by the RS encoder 120 (outer encoder), and distributes the encoded data by the interleaver 130 . In addition, the digital broadcast transmitter internally encodes the interleaved data in units of 12 symbols through the trellis encoder 140, performs mapping on the internally encoded data so that it is mapped to 8-level symbols, and inserts the field synchronization signal and the segment synchronization signal into the encoding data, performs VSB modulation on the data by inserting a pilot tone into the encoded data, and then up-converts the modulated data into an RF signal to output the RF signal.

Meanwhile, the digital broadcast receiver of FIG. 1 includes a tuner (not shown) for down-converting an RF signal received through a channel into a baseband signal. The demodulator 220 performs synchronization detection and demodulation on the converted baseband signal. The equalizer 230 compensates for channel distortion of the demodulated signal that occurs due to multipath transmission. Trellis decoder 240 performs error correction on the equalized signal and decodes the equalized signal into symbol data. The deinterleaver 250 rearranges the data distributed by the interleaver 130 of the digital broadcasting transmitter. The RS decoder 260 corrects errors, and the derandomizer 270 derandomizes the data error-corrected by the RS decoder 260, and outputs an MPEG-2 transport stream.

Accordingly, the digital broadcast receiver of FIG. 1 down-converts an RF signal into a baseband signal, demodulates and equalizes the converted signal, and then channel-decodes the demodulated signal to restore the original signal.

FIG. 2 shows a VSB data frame into which a segment sync signal and a field sync signal are inserted, used in an American-style digital broadcasting (8-VSB) system. As shown in FIG. 2, one frame includes two fields. One field includes a field sync segment as the first segment and 312 data segments. In addition, one segment in the VSB data frame corresponds to one MPEG-2 packet, and includes a segment sync signal of four symbols and 828 data symbols.

In FIG. 2, a segment sync signal and a field sync signal are used for synchronization and equalization in a digital broadcast receiver. That is, the field sync signal and the segment sync signal refer to known data between a digital broadcast transmitter and a receiver, which is used as a reference signal when equalization is performed on the receiver side.

Contents of the invention

technical problem

As shown in FIG. 1, the VSB system of the US-style digital terrestrial broadcasting system is a single-carrier system, and thus has the disadvantage of being weak in a multipath fading channel environment with Doppler effect. Therefore, the performance of the receiver is greatly affected by the performance of the equalizer used to remove multipath fading. However, according to the existing transmission frame as shown in FIG. 2, since the field sync signal (i.e., the reference signal of the equalizer) appears every 313 segments, its frequency is relatively low relative to a frame signal, which causes equalization performance degradation .

That is, existing equalizers do not easily use the aforementioned small amount of data to estimate a channel and equalize a received signal by removing multipath fading. Therefore, the conventional digital broadcast receiver has a disadvantage in that its receiving performance is degraded in a poor channel environment (especially in a Doppler fading channel environment).

Technical solutions

An aspect of the present invention is to provide a method of formatting a digital broadcast transport stream packet and a signal processing method of a digital broadcast transmitter capable of maintaining compatibility with an existing digital broadcast transmission/reception system.

Additional aspects and/or advantages of the present invention will be set forth in part in the following description, and some will be clear from the description, or can be learned through practice of the present invention.

The above and other objects are substantially achieved by providing a method for formatting a digital broadcast transport stream (TS) packet comprising a header and a payload, the method comprising inserting known Supplementary Reference Sequence (SRS) data into the packet and/or or advantages.

According to an aspect of the present invention, the packet further includes an adaptation field, and the SRS data is inserted into at least a part of the adaptation field.

According to an aspect of the present invention, the adaptation field includes an option field that is selectively included, and SRS data is inserted into at least a part of the adaptation field except the option field.

According to an aspect of the present invention, the option field is at least one of program clock reference (PCR), original program clock reference (OPCR), splice counter (splice countdown), transmission proprietary data length and adaptive field extension length or their combination.

According to an aspect of the invention, SRS signals are used for synchronization and/or channel equalization.

In another aspect of the present invention, there is provided a digital broadcast transmitter, comprising: a packet construction unit for constructing a transport stream packet, the transport stream packet including a padding area for inserting known Supplementary Reference Signal (SRS) data therein; A randomizer, which randomizes a packet including a padding area; an SRS insertion unit, which inserts SRS data into a padding area of a randomized packet; an RS encoder, which adds parity for error correction to a packet into which the SRS data is inserted ; an interleaver that interleaves the parity-added packets; a trellis encoder that performs trellis coding on the interleaved packets; a multiplexer that inserts a segment sync signal and a field sync signal into the trellis-coded packets; and a modulator /RF converter that performs vestigial sideband (VSB) modulation and RF conversion on the output signal of the multiplexer to transmit a VSB modulated and RF converted signal.

In another aspect of the present invention, there is provided a signal processing method for a digital broadcast transmitter, comprising: constructing a transport stream packet including padding for inserting known Supplementary Reference Signal (SRS) data therein area; randomize a packet including a padding area; insert SRS data into a padding area of a randomized packet; add parity for error correction to a packet with SRS data inserted; interleave a packet with parity added ; performing trellis encoding on the interleaved packets; inserting segment sync and field sync signals into the trellis encoded packets; performing vestigial sideband (VSB) modulation and RF conversion on the packets to send the VSB modulated and RF converted packets.

Beneficial effect

As described above, according to aspects of the present invention, by constructing an adaptation field including a stuffing area in an MPEG-2 transport stream packet in a digital broadcasting transmitter and inserting an SRS signal into the stuffing area, and in a digital broadcasting receiver by Detecting an SRS signal from a received signal and using the detected SRS signal for synchronization and equalization can improve reception performance of a digital broadcast receiver even in poor multipath channels.

According to aspects of the present invention, there is provided a system that is compatible with and efficiently operates with existing US-style digital broadcasting transmission/reception systems. While broadcast signals have been described as being transmitted wirelessly or by wire, it should be understood that in other aspects of the invention, transmission may occur via delayed playback recorded on a medium.

Description of drawings

These and/or other aspects and advantages of the present invention will become clearer and easier to understand through the following description of the embodiments in conjunction with the accompanying drawings, wherein:

1 is a block diagram showing the construction of a conventional digital broadcast (ATSC VSB) transmitter/receiver;

Figure 2 is a diagram illustrating the structure of an ATSC VSB data frame;

FIG. 3 is a diagram showing the structure of a Transport Stream packet;

4 is a diagram showing the structure of a header of an adaptation field of a transport stream;

5 to 9 are diagrams illustrating various data formats of MPEG-2 transport stream packets including an adaptation field to which padding bytes are added according to aspects of the present invention;

10 is a block diagram showing the configuration of a digital broadcast transmitter according to an embodiment of the present invention;

11 is a block diagram showing the configuration of a digital broadcast transmitter according to another embodiment of the present invention;

12 is a diagram illustrating input types of MPEG packets according to an aspect of the present invention;

FIG. 13 is an exemplary diagram showing the structure of an interleaved packet according to an embodiment of the present invention; and

FIG. 14 is a flowchart illustrating a signal processing method of a digital broadcast transmitter according to an embodiment of the present invention.

Detailed ways

Embodiments of the present invention will now be described in detail, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like parts throughout. The embodiments are described below in order to explain the present invention by referring to the figures. Also, well-known functions or constructions will not be described in detail since they would obscure the invention in unnecessary detail.

3 and 4 show the structure of an MPEG packet according to the MPEG system standard used in the ATSC digital television standard. As shown in Figure 3, the MPEG packet includes Sync_Byte, 1-bit transport packet error indicator, 1-bit load unit start indicator, 1-bit transport priority flag, 13-bit PID (packet identifier) value, 2-bit transport scrambling code control Indicator, 2-bit Adaptation Field Control Indicator and 4-bit Continuity Counter. The payload and/or adaptation field immediately follows the displayed 4-bit continuity counter.

As shown in Figure 4, option fields are used in MPEG packets (e.g., Program Clock Reference (PCR), Original Program Clock Reference (OPCR), slice_point, transport-specific data length, adaptation field data, and adaptation field extension flags) Information such as PCR, OPCR, splicing counter, transfer-specific data length, and adaptation field extension length are transmitted. Here, the option field can be: PCR, used as a synchronization signal for the demodulator of the receiver; OPCR, used for recording, scheduling and playback of programs in the receiver; splicing counter, which is the number of consecutive macroblocks (per macroblock Including four circuit blocks, Cr block and Cb block); transmission dedicated data length, which is the length of text data of text broadcast; and adaptive field extension length. Also shown is a 1-bit discontinuity indicator field, a 1-bit random access indicator field, a 1-bit elementary stream priority indicator field, a 1-bit adaptation field length field, and a flagged adaptation head field .

5 to 9 are diagrams illustrating MPEG-2 transport streams of various formats in which a Supplementary Reference Sequence (SRS) is inserted to implement a transmitter according to an aspect of the present invention. Here, for convenience of explanation, the three bytes following the sync byte of the transport stream are collectively referred to as a normal header, and the first two bytes of the adaptation field are collectively referred to as an adaptation field (AF) header. However, other names and/or numbers of bytes may be used.

Typically, SRS is a special known sequence inserted in certain VSB frames so that the receiver's equalizer can utilize this known sequence to mitigate dynamic multipath and other adverse channel conditions. The receiver's equalizer uses these contiguous sequences to adapt itself to the dynamically changing channel. When the encoder state is forced into a known deterministic state (DTR), an additional "known sequence" of bits computed ahead of time (SRS mode) is then immediately processed in a predetermined manner at a specific temporal location of the frame input by the interleaver. Due to the way ATSC compatible interleavers work, the resulting symbols at the output of the interleaver will appear as a known pattern of contiguous symbols in known positions in the VSB frame, which the receiver can use as an additional equalizer training sequence. The data to be used in Transport Stream (TS) packets to create these known symbol sequences is introduced into the system in a backward compatible manner using existing standard mechanisms. This data is carried in the MPEG2 adaptation field. Therefore, these existing standards are supported and compatibility is ensured.

The RS encoder in front of the interleaver calculates the RS parity. Due to resetting the TCM encoder, the calculated RS parity byte is wrong and needs to be corrected. An additional processing step therefore involves correcting parity errors in selected packets. All packets with parity errors have their RS parity re-encoded. A (52)-segment byte interleaver with unique time-diversity properties that produces contiguous SRS patterns supports using enough time to re-encode parity bytes. The time required limits the maximum number of SRS bytes.

Fig. 5 shows the structure of the basic form of MPEG-2 packet data in the VSB system using SRS. This MPEG-2 packet data includes: a normal header (including a one-byte sync signal and a three-byte PID (packet identification)), a two-byte Adaptation Field (AF) header (including about stuffing bytes) position information), and padding bytes specifying length N. The remaining bytes of the packet data correspond to the normal flow as normal payload data. Since the start position of the stuffing byte is fixed, the information on the length of the stuffing byte is used to express the information on the byte position. The stuffing byte length N can be in the range of 1 to 27.

Figures 6 to 9 show packet structures with adaptation fields to efficiently use SRS, including other parameters such as program clock reference (PCR), original program clock reference (OPCR), splice counter (splice_count), etc. information. In these cases, build adaptive fields to have a uniform size. Parts other than the AF header and information such as PCR, OPCR, splice_count, etc. correspond to stuffing bytes to be inserted into the SRS. It will be understood that, in addition to the packet structures shown in FIGS. 6 to 9 , according to aspects of the present invention, there is a construction of a transport stream having a padding area for SRS inserted in an area other than the area of the option field of the adaptation field. Many ways to pack.

FIG. 10 is a block diagram showing the configuration of a digital broadcast transmitter according to an embodiment of the present invention. 10, the digital broadcast transmitter includes a TS multiplexer (MUX) 310, a TS post-multiplexer (MUX) 320, a randomizer 330, an SRS insertion unit 340, an RS encoder 350, a data interleaver 360, a grid Encoder 370 , backward compatibility parity generator 380 and multiplexer 390 . TS MUX 310 receives video and audio streams and constructs existing MPEG transport stream packets. The post-TS MUX 320 forms a stuffing area for inserting SRS data into transport stream packets output from the TS MUX 310, and outputs the MPEG transport stream. Examples of streams by appropriately shifting positions of eg PCRs, OPCRs, splicing counters, transport proprietary data lengths, adaptive field extension lengths, and other data are shown in Figures 6 to 9 (but not limited to).

The randomizer 330 randomizes the incoming MPEG-2 transport stream data to improve the utilization of the allocated channel space. The SRS insertion unit 340 generates an SRS. The SRS is a specified sequence (for example, a training sequence) with a specified pattern arranged in advance between the transmitter side and the receiver side. The SRS insertion unit 340 replaces stuffing bytes in stuffing byte positions of the randomized data with SRSs. Since SRS is distinguishable from payload data (SRS pattern is transmitted/received), SRS can be easily detected and used for synchronization and equalization at the receiver side.

When the SRS inserting unit 340 exchanges stuffing bytes in a packet, the RS encoder 350 adds parity of a specified byte to the packet to correct an error due to a channel by performing RS encoding on packet data. The interleaver 360 interleaves the data packet to which the parity output from the RS encoder 350 is added in a specified pattern. The trellis encoder 370 converts the data output from the interleaver 360 into data symbols, and performs symbol mapping on the data symbols through trellis encoding of a code rate of 2/3.

According to an aspect of the present invention, the trellis encoder 370 initializes a value temporarily stored in its own memory device to a specified value. For example, the initialized value may be a "00" state. Whatever this value is, it is initialized at the start of the SRS. Trellis encoder 370 performs trellis encoding on the data. In addition, the trellis encoder 370 outputs the value for initializing the memory to the backward compatibility parity generator 380, receives the new parity generated by the backward compatibility parity generator 380, and uses the received The new parity replaces the corresponding existing parity such that trellis encoding is performed with the new parity received from the backward compatibility parity generator 380 .

The output of trellis encoder 370 and the next memory state are affected by previous memory values. That is, if the previous input changes, the input used for initialization changes. If the parity of the packet corresponding to the initialization area precedes the initialization area, the input value previously used to initialize the memory of the trellis encoder 370 is changed due to the newly generated parity. In this case, initialization may not be performed, or accurate parity cannot be produced using corrected initial values. Therefore, according to the aspect of the present invention, in order to prevent the parity of the initial packet from being in front of the initial area, the maximum number of stuffing bytes used according to the aspect of the present invention becomes 27. However, it should be understood that for other types of packets divided into other numbers of segments, other maximum numbers of stuff bytes used may be employed.

According to an aspect of the present invention, backward compatibility parity generator 380 performs RS encoding on MPEG-2 packets input from RS encoder 350 by using memory initialization values input from trellis encoder 370 (i.e., RS-encoded MPEG-2 packets are RS-encoded again) to generate new parity. The backward compatibility parity generator 380 sends the generated parity to the trellis encoder 370 . It should be understood that generator 380 need not be included if backward compatibility is not desired.

The MUX 390 multiplexes the trellis-coded packets, segment sync signals, and field sync signals by inserting the segment sync signals and field sync signals into the trellis-coded packets. A modulator (not shown) performs VSB modulation on the packet into which the segment sync signal and the field sync signal have been inserted, up-converts the modulated packet into an RF channel band signal to transmit the RF channel band signal.

FIG. 11 is a block diagram showing the construction of a digital broadcast transmitter according to another embodiment of the present invention. In this embodiment, the post-TS MUX 420 receives audio and video input directly (without passing through the TS MUX), and performs the same operations as the configuration of FIG. 10 . In this case, the post-TS MUX 420 is not added to the TS MUX for SRS VSB, but is considered a new TSMUX for SRS VSB.

Consistent with FIG. 10, the randomizer 430 randomizes the incoming MPEG-2 transport stream data to enhance utilization of the allocated channel space. The SRS insertion unit 440 generates an SRS of a specified sequence having a specified pattern prearranged between the transmitting side and the receiving side, and replaces stuffing bytes in stuffing byte positions of randomized data with the SRSs. The RS encoder 450 adds parity of a specified byte to the packet in which the stuffing bytes are exchanged by the SRS insertion unit 440 to correct an error due to a channel by performing RS encoding on packet data. The interleaver 460 interleaves the data packet to which the parity output from the RS encoder 450 is added in a specified pattern. The trellis encoder 470 converts the data output from the interleaver 460 into data symbols, and performs symbol mapping on the data symbols by trellis encoding of a code rate of 2/3.

As shown, the trellis encoder 470 initializes a value temporarily stored in its own memory device to a specified value (eg, initialized to a '00' state) at the start point of the SRS, and performs trellis encoding on the data. In addition, trellis encoder 470 outputs values for initializing memory to backward compatibility parity generator 480, receives new parity generated by backward compatibility parity generator 480, and uses the received The new parity replaces the corresponding existing parity.

The output of the trellis encoder and the next memory state are affected by the previous memory value. That is, if the previous input changes, the input used for initialization changes. If the parity of the packet corresponding to the initialization area precedes the initialization area, the input value previously used to initialize the memory of the trellis encoder 470 is changed due to the newly generated parity. In this case, no initialization may be performed, or accurate parity cannot be produced using the corrected initialization values. Therefore, in order to prevent the parity of the initialization packet from being in front of the initialization area, the maximum number of stuffing bytes used becomes 27.

The backward compatibility parity generator 480 generates parity by performing RS encoding on the MPEG-2 packet input from the RS encoder 450 using the memory initialization value input from the trellis encoder 470, and generates parity The checksum is sent to trellis encoder 470 . However, it is understood that generator 480 is not required in all aspects of the invention.

The MUX 490 multiplexes the trellis-coded packets, segment sync signals, and field sync signals by inserting the segment sync signals and field sync signals into the trellis-coded packets. A modulator (not shown) performs VSB modulation on the packet into which the segment sync signal and the field sync signal have been inserted, and up-converts the modulated packet into an RF channel band signal to transmit the RF channel band signal.

12 is a diagram illustrating an exemplary input type of an MPEG packet according to aspects of the present invention so that SRS VSB can be effectively operated. 312 MPEG packets are contained in one VSB field. Among the 312 packets, packets including information such as PCR, OPCR, splicing counter, transfer-specific data length, and adaptation field extension length can be input at designated positions as shown in the drawing. For example, when 312 segments are divided in units of 52 segments, the position of the option field can be expressed as follows:

Program clock reference (PCR) (uses 6 bytes): 52n+15, n=0;

Original Program Clock Reference (OPCR) (6 bytes used): 52n+15, n=1;

Adaptive field extension length (using 2 bytes): 52n+15, n=2;

Transmission proprietary data length (using 5 bytes): 52n+15, n=3, 4, 5; and

Splicing counter (using 1 byte): 52n+19, n=0, 1, 2, 3, 4, 5.

The formation of MPEG packets as shown in FIG. 5 and the location of MPEG packets as shown in FIG. 12 can be modified in various forms to effectively use SRS VSB.

FIG. 13 is an exemplary diagram illustrating the structure of an interleaved packet according to an embodiment of the present invention. For compatibility reasons, MPEG information such as PCR should be received as is, therefore, it cannot be used for initialization or SRS mode. Therefore, by transmitting the MPEG information using the transport stream portion that does not initialize the trellis encoder 370, loss can be reduced.

As shown in Figure 12, when PCR or OPCR is used at position 52n+15, 5 bytes out of 6 bytes of PCR or OPCR are used in the empty part where no known symbols are used, which results in only one byte The loss of known symbols (ie, 4 symbols) without any training loss occurs. In addition, no known symbol loss occurs in cases where less than 5 bytes of information are transmitted. In Figure 12, splice_count is sent at position 52n+19. By sending splice_count without using the empty part of known symbols as shown in FIG. 13, splice_count can be sent without any loss of known symbols. In the case of using an MPEG packet having the above structure, the receiver uses the SRS region other than the OPCR and PCR regions as a training sequence, specifically, for an equalizer (e.g., equalizer 230) and/or preamble A known value to an error correction decoder (eg, decoder 240).

Next, an embodiment of a method of compatible operating the SRS VSB when there is no post-TS MUX will be explained. When the MPEG packet is input to the data randomizer 330, the randomizer 330 uses the adaptation field control flag of FIG. 3 to judge whether the adaptation field exists. As shown, the adaptive field control flag of Fig. 3 has a reserved flag (00), a flag (01) without an adaptive field and only a payload, a flag (10) with only an adaptive field without a payload, and an adaptive field followed by Load flags (11). If the adaptation field exists, the data randomizer 330 judges whether OPCR, splicing_point, transport_private_data, and adaptation_field_exension exist using flags as shown in FIG. 4 . If there is even a flag, it passes through the corresponding packet without performing padding byte replacement.

In this case, trellis encoder 370 and backward compatibility parity generator 380 of FIG. 10 process packets in existing VSB processing without performing RS re-encoding and memory initialization on the training sequence. In this process, the packet carrying the information is unchanged so that the packet can be sent without distortion.

The transmitter can use the reserved portion to send such information by sending information about changes in the training area to the receiver. In addition, the receiver uses the information on the training region as a known value for an equalizer and backward error correction by using the information as a training sequence.

FIG. 14 is a flowchart illustrating a signal processing method for a digital broadcast transmitter according to an embodiment of the present invention. Referring to Figures 6a and 9, TS MUX 310 receives video streams and audio streams, and builds transport stream packets. The post-TS MUX 320 constructs a transport stream packet including a padding area for inserting known SRS data (S910). The randomizer 330 randomizes the packet including the padding area (S920). The SRS insertion unit 340 inserts the SRS signal into the stuffing area of the randomized packet (S930).

The RS encoder 350 adds parity to the packet into which the SRS signal has been inserted to correct an error due to a channel (S940). The interleaver 360 interleaves the packet to which the parity has been added (S950). The trellis encoder 370 initializes its own memory at the start point of the SRS signal, and performs trellis encoding (S960). The backward parity generator 380 receives the packet to which the parity has been added by the RS encoder 350 and the packet encoded by the trellis encoder 370 at operation S940, and generates compatibility parity on the basis of the above packet (S970 ). Trellis encoder 370 receives the compatibility parity from backward compatibility parity generator 380 and replaces the neutral and compatibility parity with the parity added by RS encoder 350 with the generated compatibility parity corresponding part, and perform trellis encoding using the parity in operation S960.

The multiplexer 390 inserts the segment sync signal and the field sync signal into the trellis-coded packet (S980), and the modulator performs VSB modulation and RF conversion on the packet to transmit the VSB modulated and RF-converted packet (S990).

Although a stream including audio and video is shown, it should be understood that the stream may include other data in accordance with aspects of the invention.

While not required in all aspects, it should be understood that aspects of the invention may be implemented as hardware, software or a combination thereof. While a few embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that such embodiments may be modified without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents. Make changes.

Industrial availability

Aspects of the present invention relate to a method for formatting a digital broadcast transport stream packet, a digital broadcast transmitter and a signal processing method thereof, and more particularly, to a method for generating an adaptive field in a transport stream packet and Method of formatting digital broadcast transport stream packets by inserting known data (i.e. Supplementary Reference Sequence "SRS") into the position of the adaptation field to improve the reception performance of the receiving system and maintain compatibility with existing systems, a digital Broadcast transmitter and its signal processing method.

Claims (4)

1. digital broadcasting transmitter comprises:

Demodulator receives stream, and the stream that receives is carried out demodulation;

Equalizer carries out equilibrium to the stream of demodulation;

Decoder is handled balanced stream,

Wherein, stream comprises the data that are placed on the predefined type in the precalculated position in the stream by digital broadcast transmitter, wherein, at least one in demodulator, equalizer and the decoder detects the data of described predefined type from described precalculated position, and uses the data of this detection.

2. digital broadcasting transmitter as claimed in claim 1, wherein, the data of described predefined type are to replenish one of reference sequences, program clock reference, original program clock reference, splicing counter, transmission proprietary data length and self adaptation field extension length.

3. method of handling the stream of digital broadcasting transmitter comprises:

Receive stream, and the stream demodulation to receiving;

Stream to demodulation carries out equilibrium;

To the stream decoding of equilibrium,

Wherein, stream comprises the data that are placed on the predefined type in the precalculated position in the stream by digital broadcast transmitter, wherein, at least one in demodulation, equilibrium and the decoding step comprises: detect the data of described predefined type from described precalculated position, and use the data of this detection.

4. method as claimed in claim 3, wherein, the data of described predefined type are to replenish one of reference sequences, program clock reference, original program clock reference, splicing counter, transmission proprietary data length and self adaptation field extension length.

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