KR20040035297A - Apparatus and method for transmission of digital broadcasting system having the composition error correction coding function - Google Patents

Abstract

PURPOSE: A transmission device of a digital broadcasting system having a complex ECC(Error Correction Coding) function is provided to differently perform ECC processes for data transmitted through an HP(High Priority) layer and data transmitted through an LP(Low Priority) layer in consideration of communication environments, thereby improving transmission efficiency of a system. CONSTITUTION: The first and second RS encoders(112,122) encode the first and second TSs(Transport Streams) to enable ECC functions, respectively. The first and second outer interleavers(114,124) re-array data encoded in the first and second RS encoders(112,122), respectively. A convolution encoder(116) convolution-encodes the data re-arrayed in the first outer interleaver(114). A turbo encoder(126) encodes the data re-arrayed in the second outer interleaver(124) to enable an ECC function. An inner interleaver(128) re-arrays the data encoded in the convolution encoder(116) and the data encoded in the turbo encoder(126), respectively. A modulator portion(140) digitally modulates the re-arrayed data, and transmits the modulated data.

Description

Apparatus and method for transmission of digital broadcasting system having the composition error correction coding function

The present invention relates to a transmission apparatus and method for a digital broadcasting system having a complex error correction encoding function. More particularly, in a digital broadcasting system supporting a hierarchical transmission mode, data can be transmitted by different error correction coding for each transport layer. The present invention relates to a transmission apparatus and method for a digital broadcasting system having a complex error correction encoding function.

Digital broadcasting, which transmits and receives broadcast signals by digitally encoding them, has the advantage of system integration and interoperability through digital coding systems, unlike analog broadcasting. This advantage allows digital broadcasting to become the core of the so-called media convergence that mobilizes computers and networks. In addition, the digital broadcasting has an interactive function, which is a chance for a new conversion of the unilateral and downward analog broadcasting domain.

In order to ensure the integration and interoperability of digital broadcasting, standardization must precede. For digital terrestrial DTV (Digital Television) broadcasting, DVB-T in Europe based on the US Advanced Television Systems Committee (ATSC) method using 8-VSB (Vestigial Side Band) and Coded Orthogonal Frequency Division Multiplexing (COFDM) (Digital Video Broadcasting-Terrsetrial) broadcasting method has been proposed. In addition, Terrestrial Digital Multimedia Television Broadcasting (DMB-T) based on Time-Domain Synchronous Orthogonal Division Frequency Multiplexing (TDS-OFDM), Advanced Digital Television Broadcast-Terrestrial (ADTB-T) with improved VSB, and SMCC (COCCDM) with improved COFDM Various broadcast methods such as Synchronized multi-Carrier CDMA, CDTB-T (Chinese Digital Television Broadcasting-Terrestrial), and BDB-T have been proposed by various organizations.

When transmitting digital broadcasting, data must be compressed and transmitted to transmit a huge amount of data. Therefore, even if a small error occurred in a channel during transmission, the effect on the entire system is very large. Therefore, it is necessary to reduce the error occurring in the channel during transmission. Basically, in order to reduce the error, the power is increased to increase the SNR, but when the power is increased, problems such as power loss, cost increase due to high output of the transmission apparatus, and interference between channels occur. To solve this problem, digital broadcasting systems use error correction codes to correct errors occurring in channels instead of increasing power.

The error correction code can be broadly divided into ARQ (Automatic Repeat Request) and FEC (Forward Error Correction). Here, the ARQ is a method of transmitting a signal to retransmit the data when the error is detected in the receiving device, and thus retransmits the data detected by the transmitting device. This method is not suitable for digital broadcasting systems because it requires a return channel capable of transmitting a signal for retransmission from the receiving apparatus to the transmitting apparatus. On the other hand, the FEC transmits an additional symbol appended to the signal and detects or corrects a channel error by using an algebraic property in the receiver when an error occurs in the channel.

FEC can be roughly divided into a block code and a convolution code. The block code is encoded and decoded by dividing the information into blocks, and includes a Hamming code, a BCH code, and a Reed Solomon (RS) code. Among them, RS codes are most commonly used in digital broadcasting systems because of their excellent distance characteristics and efficient encoding and decoding algorithms. Since RS codes detect and correct errors on a block basis, the ability to correct burst errors is excellent.

In contrast, a convolution code is a code whose output bit is affected not only by the current input bit but also by the past input bit, and is effective for correcting a random error. Convolutional codes include Viterbi code, Turbo code, and the like. Here, the turbo code has a relatively simple decoding algorithm and shows breakthrough performance. The turbo code has the advantage that iterative decoding is possible and the size of the interleaver can be adjusted.

On the other hand, since the error-corrected data must transmit additional information for error correction, the amount of information that can be transmitted per limited bandwidth is reduced. Accordingly, a transmission method that can obtain a large code gain without reducing the data rate or increasing the bandwidth by combining the encoding and the modulation together without a separate one, is typical of TCM (Trellis Coded Modulation) There is.

1 is a block diagram of a transmission apparatus of a digital broadcasting system according to the DVB-T method.

Referring to the drawings, a transmission apparatus of a digital broadcasting system includes first and second scramblers 10 and 11, a forward error correction unit 30, and a modulator 40. The FEC unit 30 includes first and second RS encoders 12 and 22, first and second outer interleavers 14 and 24, first and second convolutional encoders 16 and 26, And an inner interleaver 28. The modulator 40 includes a pilot / system information inserter 41, a mapping / OFDM modulator 43, a guard section inserter 45, a D / A converter 47, and an RF section 49. It consists of.

In the case of the DVB-T scheme, a hierarchical transmission mode is supported, and in this case, the inputted TS-2 transport stream of the MPEG-2 format is separated by a splitter (not shown) by HP (High Priority). ) And a first TS stream transmitted to the HP layer is input to the first scrambler 10, and a second TS stream transmitted to the LP layer is transmitted to the second scrambler 11. Is entered.

The first and second scramblers 10 and 11 change the data values of the first and second TS streams of the MPEG-2 format inputted according to a predetermined pattern and randomize them. This process is reversed in the receiver to restore the original value.

The FEC unit 30 encodes data input through the first and second scramblers 10 and 11 to correct an error that may occur during transmission. That is, the first and second RS encoders 12 and 22 receive the data passing through the first and second scramblers 10 and 11 and perform RS encoding to enable error correction. By RS coding, a parity for error correction is added, and the number of parities added varies depending on the transmission scheme. In the case of the DVB-T system, 16 parities are added per TS stream of 188 bytes, and the error correction coded total bytes are 204 bytes.

The first and second external interleavers 14 and 24 rearrange the RS-coded data in the first and second RS encoders 12 and 22, respectively, to perform a function of distributing likely coherence errors. . The first and second convolutional encoders 16 and 26 convolutionally encode data output from the first and second external interleavers 14 and 24 rearranged in units of symbols. In the DVB-T scheme, it is common to use a convolutional code having a constraint length of 7 and a code rate of 1/2.

The bits convolutionally coded by the first and second convolutional encoders 16 and 26 are rearranged and output by the internal interleaver 28.

The modulator 40 performs appropriate digital modulation on the transmission method of the digital broadcasting system on the data encoded and output by the FEC unit 30. As shown in FIG. 1, when the OFDM scheme of the DVB-T system is used, the mapping / OFDM modulator 43 performs quadrature phase shift keying (QPSK), 16-QAM, on data output from the internal interleaver 28. OFDM modulation such as mapping to symbols such as Quadrature Amplitude Modulation, 64-QAM, and Inverse Fast Fourier Transform (IFFT). In this process, the pilot / system information insertion unit 41 inserts information on the signal synchronization and the pilot signal for the signal prediction and the transmission mode. The guard interval inserter 45 inserts a guard interval to prevent inter symbol interference (ISI) in a multipath environment. In addition, the D / A converter 47 performs a D / A (Digital to Analog) conversion on the signal into which the protection interval is inserted, and the RF unit 49 amplifies the D / A-converted signal by high-frequency amplification. Send through.

As described above, in the transmission apparatus of the conventional digital broadcasting system, the first and second RS encoders 12 and 22 are used as outer encoders, and the first and second encoders are used as inner encoders. The concatenated code system, which uses the convolutional encoders 16 and 26, is mainly used. In addition, in the case of a transmitter of a digital broadcasting system supporting a hierarchical transmission mode such as DVB-T, an encoder using the same coding scheme in the HP layer and the LP layer and an interleaver performing interleaving by the same scheme are used. .

As described above, in case of error correction encoding using the encoder and interleaver of the same specification in the HP layer and the LP layer, both the data transmitted through the HP layer and the data transmitted through the LP layer are received using a receiver having the same structure. There is the convenience of doing it.

However, the receiver using the HP layer and the receiver using the LP layer may exist in different communication environments, and in this case, separate error correction coding may improve the transmission efficiency of the system according to the communication environment of the receiver. have. For example, a receiving device in a mobile communication environment needs to receive a better signal, and a receiving device in a fixed state may require receiving more data. In this case, reception performance may be improved by performing enhanced error correction encoding on data transmitted through the HP layer, and may be configured to have a faster data rate for data transmitted through the LP layer. Accordingly, there is a need for a transmission apparatus and method for a digital broadcasting system having a complex error correction encoding function using different error correction encoding schemes according to layers in consideration of a communication environment of a receiver.

The present invention has been made to solve the above problems, an object of the present invention, the data transmitted through the HP layer and the data transmitted through the LP layer differently complex error in consideration of the communication environment of the receiver. Disclosed are a transmission apparatus and a method of a digital broadcasting system capable of transmitting by correcting encoding.

1 is a block diagram of a transmission apparatus of a general digital broadcasting system.

2 is a block diagram of an embodiment of a transmission apparatus of a digital broadcasting system according to the present invention;

3 is a flowchart provided to explain an operation method for a transmission apparatus of the digital broadcasting system of FIG.

4 is a block diagram of another embodiment of a transmission apparatus of a digital broadcasting system according to the present invention;

FIG. 5 is a flowchart provided to explain an operation method of the transmission apparatus of the digital broadcasting system of FIG. 4.

Explanation of symbols on the main parts of the drawings

110: first scrambler 111: second scrambler

130: FEC unit 112: the first RS encoder

114: first external interleaver 116: convolution encoder

122: second RS encoder 124: second external interleaver

126 turbo sign 128 internal interleaver

140: modulation unit 141: pilot / system information insertion unit

143: mapping / OFDM modulator 145: protection section insertion unit

147: D / A converter 149: RF unit

In order to achieve the above object, a transmission apparatus of a digital broadcasting system according to the present invention separates an input TS stream of an MPEG-2 format into a first TS stream and a second TS stream so that error correction is possible. In the transmission apparatus of a digital broadcasting system for encoding, first and second encoders for encoding error correction for the first and second TS streams, and data encoded by the first and second encoders, respectively, are cultivated. A first and second external interleaver to concatenate, a convolution encoder to convolutionally encode data rearranged in the first external interleaver, an internal encoder to encode data rearranged in the second external interleaver to enable error correction; An internal interleaver for rearranging data encoded by the convolutional encoder and data encoded by the internal encoder, respectively; Modulation unit includes transmitting the digital modulation to the data rearranged in the internal interleaver group. In this case, it is preferable that the internal encoder encodes an error correction using a turbo code or encodes an error correction using a turbo-TCM code.

The internal interleaver may rearrange the data encoded by the convolutional encoder and the data output from the internal encoder in the same manner. The internal interleaver may rearrange the data output from the convolutional encoder and the data output from the internal encoder in different ways.

Preferably, the first and second encoders are Reed-Solomon encoders encoded using Reed-Solomon codes. At this time, the first and second encoders can be error-corrected encoded by RS codes having different specifications.

Preferably, the modulator digitally modulates by an OFDM modulation method. In this case, the modulator may include: a mapping / OFDM modulator for mapping and OFDM modulating data rearranged by the internal interleaver by a predetermined mapping method, a pilot signal for signal synchronization and a signal prediction unit for the mapping / OFDM modulator; A system information insertion unit providing information on a transmission mode, a protection interval insertion unit inserting a guard interval into a signal output from the mapping / OFDM modulator, and a D / A converting the signal into which the guard interval is inserted It is possible to comprise a conversion unit and an RF unit which transmits the D / A-converted signal by high frequency conversion.

Preferably, the apparatus further includes first and second scramblers for randomizing the first and second TS streams and supplying the first and second encoders, respectively.

On the other hand, in the transmission method of the digital broadcasting system according to the present invention, the TS stream (transport stream) of the MPEG-2 format is input into a first TS stream and a second TS stream and encoded so as to enable error correction, respectively, ( a) outputting first and second encoded data encoded to enable error correction for the first and second TS streams, respectively; (b) rearranging the first and second encoded data, respectively, to form a first And outputting second rearranged data, (c) convolutionally encoding the first rearranged data, (d) internally encoding the second rearranged data to enable error correction, and (e) Rearranging the convolutionally encoded data and the internally encoded data, respectively, and (f) digitally modulating and transmitting the rearranged data. In this case, in the step (d), it is preferable that error correction encoding is performed using a turbo code or error correction encoding is performed using a turbo-TCM code.

In the step (e), it is possible to rearrange the convolution coded data and the internal coded data in the same manner. Also, in the step (e), the convolution coded data and the internal coded data may be rearranged in different ways.

In the step (a), it is preferable to encode using a Reed-Solomon code. In this case, in step (a), the first and second encoded data may be error corrected encoded by RS codes having different specifications.

In the step (f), it is preferable to perform digital modulation by the OFDM modulation method. In this case, step (f) may include: (f1) mapping and OFDM modulating the rearranged data by a predetermined mapping method, and (f2) the pilot signal and the transmission mode for signal synchronization and signal prediction. Providing information about the OFDM modulation process, (f3) inserting a guard interval into the signal output in the step (f2), (f4) D / A converting the signal having the guard interval inserted therein, And (f5) converting the D / A-converted signal into high-frequency conversion.

Preferably, the method further comprises randomizing the first and second TS streams and supplying them to the step (a).

Hereinafter, with reference to the drawings will be described the present invention in more detail.

2 is a block diagram showing an embodiment of a transmission apparatus of a digital broadcasting system according to the present invention.

Referring to the drawings, the transmission apparatus of the digital broadcasting system according to the present embodiment is largely composed of the first and second scramblers 110 and 120, the FEC unit 130, and the modulator 140. The FEC unit 130 includes the first and second RS encoders 112 and 122, the first and second external interleavers 114 and 124, the convolution encoder 116, the turbo encoder 126, and the internal interleaver ( 128). The modulator 140 includes a pilot / system information inserter 141, a mapping / OFDM modulator 143, a guard interval inserter 145, a D / A converter 147, and an RF unit 149. It consists of.

The transmission apparatus of the digital broadcasting system according to the present embodiment supports a hierarchical transmission mode, and a TS stream of the MPEG-2 format is separated from the HP by a splitter (not shown). The first TS stream, which is divided into a High Priority layer and a Low Priority (LP) layer, and is transmitted to the HP layer, is input to the first scrambler 110, and the second TS stream transmitted through the LP layer is a second scrambler ( 111).

The first and second scramblers 110 and 111 randomize the data values of the input first and second TS streams according to a predetermined pattern. That is, the correlation of the input signal is eliminated by mixing the pseudo random binary sequence with the input TS stream of the MPEG-2 format. This is to prevent the problem that the same number is repeated, such as 00000000b or 11111111b, and loses the synchronization signal in the synchronous data transmission. This process is reversed in the receiver to restore the original value.

The FEC unit 130 performs coding for error correction that may occur during transmission on data input through the first and second scramblers 110 and 111. That is, the first and second RS encoders 112 and 122 receive data passing through the first and second scramblers 110 and 111 and perform RS encoding in units of blocks for error correction. By the RS encoding, a parity for error correction is added, and parities added by the first and second RS encoders 112 and 122 may be encoded in the same manner or differently encoded.

The first and second external interleavers 114 and 124 perform interleaving to rearrange the data output from the first and second RS encoders 112 and 122 in units of bytes.

The convolution encoder 116 convolutionally encodes the data output from the first external interleaver 114, and the turbo coder 126 converts the data output from the second external interleaver 260 into a turbo code. Encoding using a Turbo-TCM (Turbo-TCM) code. Convolutionally coded data or turbo coded or turbo-TCM coded data are rearranged by the internal interleaver 128 and output to the modulator 140. The internal interleaver 128 may be composed of a bit interleaver and a symbol interleaver. In this case, the bit interleaver performs interleaving of input data in units of bits, and the symbol interleaver uses one effective carrier in an OFDM symbol in the OFDM scheme. Interleaving is performed in symbol units.

The modulator 140 performs appropriate digital modulation on the transmission method of the digital broadcasting system on the data encoded and output by the internal interleaver 128. 2 illustrates a case of performing modulation based on the OFDM scheme of the DVB-T system.

In this case, the mapping / OFDM modulator 143 of the modulator 140 may use Quadrature Phase Shift Keying (QPSK), Quadrature Amplitude Modulation (QAM), 64-QAM, or the like, for the data output from the internal interleaver 128. OFDM modulation such as mapping and Inverse Fast Fourier Transform (IFFT) are performed with the same symbol. During this process, the pilot / system information insertion unit 141 inserts information on the signal synchronization, the pilot signal for the signal prediction, and the transmission mode. The guard interval inserting unit 145 inserts a guard interval (GI) to prevent intersymbol interference (ISI) in a multipath environment. In addition, the D / A converter 147 performs a digital-to-analog (D / A) conversion on the signal having the guard interval inserted therein, and the RF unit 149 amplifies the D / A-converted signal by high frequency amplification. Send through.

3 is a flowchart provided to explain an operation method for a transmission apparatus of a digital broadcasting system according to the present invention shown in FIG.

Referring to the flowchart, a TS stream in MPEG-2 format inputted first is transmitted through a TS stream transmitted through a HP (High Priority) layer by a splitter (not shown) and a Low Priority (LP) layer. The stream is divided into TS streams (S300). First, if it is assumed that the TS stream transmitted through the HP layer is the first TS stream, the first TS stream separated by the separator (not shown) is input to the first scrambler 110, and the first scrambler 110 is provided. In operation S302 and S304, scrambling is performed to randomize an input TS stream of the MPEG-2 format.

MPEG-2 defines two multiplexing methods, namely, program stream and TS stream, to cope with various applications. Multiplexing is the creation of a single bitstream that is combined to transmit individually compressed video, audio, and data streams. Program stream is a multiplexing method defined for media with relatively low error or loss of data such as CD-ROM, and TS stream is a multiplexing method defined for an environment where transmission error or data loss may occur such as a noisy channel. to be. One packet of the multiplexed string is of fixed size of 188 bytes.

The first RS encoder 112 performs RS encoding on a block-by-block basis for error correction on the scrambled data passing through the first scrambler 110 (S306).

The RS (Reed Solomon) code is a non-binary block code. The element is not composed of only 0 or 1, but is composed of 0, 1, ..., 2 ^{m < -1} > By RS coding, one block composed of k input symbols is encoded into n code symbols larger than k. Therefore, nk redundant symbols are added, which is called Reed Solomon Parity. The number of parities added by RS encoding may vary depending on the transmission scheme, such as 16 or 20 per 188-byte symbol. The receiver uses the added parity to determine the accuracy of the received data. As a result of the accuracy determination, if an error is detected, the receiver locates the error, corrects the distorted data, and restores the original signal. In general, error recovery is possible as many as half of the number of added parity symbols, and more errors cannot be recovered.

The first external interleaver 114 performs external interleaving which rearranges the data encoded in units of blocks in the first RS encoder 112 (S308). There are various ways in which the first external interleaver 114 rearranges data, but in general, a convolutional interleaver is used. The convolution interleaver cyclically writes each input symbol or bit into one of the predetermined shift registers, and when the shift register is read cyclically, the interleaved symbols are output. The interleaver basically does the job of distributing burst errors as large as possible.

The convolution encoder 116 convolutionally encodes the data output from the first external interleaver 214 (S310). The convolutional code encodes each successive input sequence of k bits into n output bits, and the encoding consists of the convolution of the input bits and the binary impulse response. In the case of the DVB-T transmission method, a convolutional coding method having a constraint length of 7 and a coding rate of 1/2 is used, but the coding rates of the convolution are 2/3, 3 / 4, 5/6, 7/8, etc. can be changed.

The internal interleaver 128 interleaves the data convolutionally encoded by the convolutional encoder 116 again (S322) to improve performance degradation due to multipath. As described above, the error-corrected coded data is digitally modulated for data transmission by the modulator 140 and transmitted (S330).

Meanwhile, when the TS stream transmitted through the input LP layer is referred to as the second stream, as described above, the second TS stream separated by the separator (not shown) is input to the second scrambler 111 and scrambled. In operation S314, the scrambled data is RS encoded by the second RS encoder 122. In operation S316, the second RS encoder 122 may be encoded to the same specification as that of the first RS encoder 112. Alternatively, you can code.

The second external interleaver 124 performs interleaving to rearrange the data encoded by the second RS encoder 124 (S318), thereby distributing the coherence error that may occur in the channel.

The turbo encoder 126 turbo encodes the data rearranged from the second external interleaver 124 so as to enable error correction again (S320).

The turbo code was proposed by Berrou et al. In general, a turbo encoder is a structure using two RSC (Recursive Systematic Convolutional) encoder in parallel, it can be configured in a desired size in consideration of the error correction capability. An interleaver is arranged between the two RSC encoders to rearrange the order of the data input to the second RSC encoder, so that the coherence error is treated as a sporadic error. Turbo code can achieve desired bit error rate (BER) performance by adjusting the iterative decoding and interleaver size.

The turbo code unit 126 may be encoded using a turbo-TCM code in addition to the turbo code. Trellis Coded Modulation (TCM) combines code codes and modulation separately, so that large code gains can be obtained without reducing information rate or bandwidth. Turbo-TCM encoding simultaneously performs such a TCM and turbo encoding function.

The data encoded by the turbo encoder 126 is transferred to the internal interleaver 128, and the internal interleaver 128 interleaves the transferred data and rearranges the data again (S322). The error correction coded data is digitally modulated for data transmission by the modulator 140 and transmitted through an antenna (S330).

In this manner, data transmitted to the HP layer and data transmitted to the LP layer can be transmitted by differently performing error correction encoding.

4 is a block diagram showing another embodiment of a transmission apparatus of a digital broadcasting system according to the present invention.

Referring to the drawings, a transmission apparatus of a digital broadcasting system includes first and second scramblers 210 and 211, an FEC unit 230, and a modulator 240. FEC unit 230 includes first and second RS encoders 212 and 222, first and second external interleavers 214 and 224, convolutional encoder 216, turbo encoder 226, first and second internals. Interleavers 218 and 228. The modulator 240 includes a pilot / system information inserter 241, a mapping / OFDM modulator 243, a guard interval inserter 245, a D / A converter 247, and an RF unit 249. It consists of.

The difference between the transmission apparatus of the digital broadcasting system according to the present embodiment and the transmission apparatus of the digital broadcasting system shown in FIG. 2 is that only one internal interleaver 128 is used in FIG. By using the first and second internal interleavers 218 and 228, data encoded and output by the convolutional encoder 216 and the turbo encoder 226 can be interleaved in a separate manner. The functions of the remaining blocks are as described in FIG.

FIG. 5 is a flowchart provided to explain an operation method of the transmission apparatus of the digital broadcasting system of FIG. 4.

Referring to the flowchart, unlike the flowchart of FIG. 3, the first internal interleaver 218 interleaves data output from the convolution encoder 216 (S410 and S412), and the turbo code or turbo TCM encoder 226. There is a difference in the step of interleaving the output data in the second internal interleaver 228 (S420, S422). That is, the data output from the convolutional encoder 216 and the turbo encoder 226 can be interleaved in a different manner, different from the flowchart of FIG. 3, and the operations of the remaining steps are the same as those described with reference to FIG. 3.

As described above, the transmitter of the digital broadcasting system according to the present invention adds error correction codes to the data transmitted through the HP layer and the data transmitted through the LP layer differently, and the interleaving scheme is also different from each other. It is possible to configure differently. As described above, the error correction coding is performed differently according to the layer to be transmitted, thereby enabling efficient transmission suitable for the communication environment of the receiving apparatus.

In addition, in the above embodiment, a case of modulating using the OFDM scheme has been described as an example. However, the present invention is applicable to a transmission apparatus of various digital broadcasting systems without being limited to the modulation scheme, thereby optimizing for a communication environment of the receiver. Enable the transfer of the data.

As described above, according to the present invention, error correction encoding is performed on the data transmitted through the HP layer and the data transmitted through the LP layer to perform error correction encoding according to a communication environment of a receiving apparatus. Makes it possible. Therefore, the transmission efficiency of the system can be improved by using the error correction code optimized according to the communication environment of the receiver.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the specific embodiments described above, but the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be understood individually from the technical idea or the prospect of the present invention.

Claims (20)

A transmission apparatus of a digital broadcasting system for separating an input TS stream in an MPEG-2 format into a first TS stream and a second TS stream, and encoding the error stream for error correction. First and second encoders configured to perform error correction on the first and second TS streams, respectively; First and second external interleavers for rearranging data encoded by the first and second encoders, respectively; A convolution encoder which convolutionally encodes the rearranged data in the first external interleaver; An internal encoder for encoding data rearranged by the second external interleaver to enable error correction; An internal interleaver for reordering the data encoded by the convolutional encoder and the data encoded by the internal encoder; And And a modulator for digitally modulating and rearranging the data rearranged by the internal interleaver. The method of claim 1, And the internal encoder performs error correction encoding using a turbo code. The method of claim 1, The internal encoder is error correction encoding using a Turbo-TCM code, characterized in that the transmission device of the digital broadcasting system. The internal interleaver, And the data encoded by the convolutional encoder and the data output from the internal encoder are rearranged in the same manner. The method of claim 1, The internal interleaver, And the data output from the convolutional encoder and the data output from the internal encoder are rearranged in different ways. The method of claim 1, And the first and second encoders are Reed-Solomon encoders that encode using Reed-Solomon codes. The method of claim 6, And the first and second encoders perform error correction encoding on RS codes having different specifications. The method of claim 1, The modulator is a digital broadcast system, characterized in that for digital modulation by the OFDM modulation method. The method of claim 8, The modulator, A mapping / OFDM modulator for mapping and OFDM modulating the data rearranged by the internal interleaver by a predetermined mapping method; A system information insertion unit providing information on a pilot signal and a transmission mode for signal synchronization and signal prediction to the mapping / OFDM modulation unit; A guard section inserting section which inserts a guard section into a signal output from the mapping / OFDM modulator; A D / A converter configured to D / A convert the signal with the guard interval inserted therein; And And a RF unit for transmitting the D / A-converted signal by high frequency conversion and transmitting the same. The method of claim 1, And randomizing the first and second TS streams and supplying the first and second TS streams to the first and second encoders, respectively. In the transmission method of the digital broadcasting system for separating the input TS stream (transport stream) of the MPEG-2 format into a first TS stream and a second TS stream so as to enable error correction, respectively. (a) outputting first and second encoded data encoded to enable error correction on the first and second TS streams, respectively; (b) rearranging the first and second encoded data, respectively, and outputting first and second rearranged data; (c) convolutionally coding the first rearrangement data; (d) internally encoding the second rearranged data to enable error correction; (e) reordering the convolutionally coded data and the internally coded data, respectively; And and (f) digitally modulating and transmitting the rearranged data. The method of claim 11, In the step (d), error correction encoding is performed using a turbo code. The method of claim 10, In the step (d), error correction encoding is performed using a Turbo-TCM code. The method of claim 11, In step (e), And transmitting the convolution coded data and the internal coded data in the same manner. The method of claim 11, In step (e), And the rearranged convolutionally encoded data and the internally encoded data in different ways. The method of claim 11, In the step (a), the Reed-Solomon code is encoded using a transmission method of a digital broadcasting system. The method of claim 16, In the step (a), the first and second coded data, error correction encoding method using a RS code having different specifications. The method of claim 11, In the step (f), the digital broadcasting system is characterized by digital modulation by OFDM modulation. The method of claim 18, Step (f), (f1) mapping and OFDM modulating each of the rearranged data by a predetermined mapping method; (f2) providing information on a pilot signal and a transmission mode for signal synchronization and signal prediction to the OFDM modulation process; (f3) inserting a guard interval into the signal output in step (f2); (f4) D / A converting the signal into which the guard interval is inserted; And (f5) transmitting the D / A-converted signal by high-frequency conversion; transmitting the digital broadcasting system. The method of claim 11, Randomizing the first and second TS streams, and supplying the first and second TS streams to the step (a).