CN1841973A

CN1841973A - Transmission device of digital broadcasting system having complex error correction coding function and transmission method thereof

Info

Publication number: CN1841973A
Application number: CNA2006100766340A
Authority: CN
Inventors: 金纪甫
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2002-10-19
Filing date: 2003-05-08
Publication date: 2006-10-04
Also published as: KR100902295B1; CN1263299C; CN1490946A; KR20040035289A

Abstract

The invention relates to a sending device with combined correct code function in digit broadcast system and relative method, wherein said device comprises: a RS coder for RS coding the first input transmission stream (TS); a BPC coder for coding the second TS stream with BPC code to correct; the first and second external interlace devices for interlacing the data coded by RS coder and the data coded by BPC coder; the first and second internal coders for convolutionally coding the data that interlaced by first and second external interlace devices; an internal interlace device for interlacing the data coded by first and second internal coders; and a modulator for digitally coding the data interlaced by internal interlace device, to send the modulated data. Therefore, the invention can execute different correction code based on the communication environment of receiver, to improve the sending efficiency of whole system.

Description

Digital broadcasting system transmitter and method with complex error correction coding function

The application is to be that May 8, application number in 2003 are 03130679.9, are entitled as the dividing an application of patent application of " digital broadcasting system transmitter and method with complex error correction coding function " applying date.

Technical field

The present invention relates to have the digital broadcasting system transmitter and the method for complex error correction coding function, more specifically, relate to a kind of dispensing device and method of supporting the digit broadcasting system of Delamination Transmission pattern, it can carry out different error correction to coded data according to the transmission level.

Background technology

Digit broadcasting system is used for the digital coding broadcast singal, send this signal receives this signal to satellite and ground passage and by receiving system.Compare with analog broadcasting, digit broadcasting system has the ability of comprehensive and collaborative work by using digital encoding system.In addition, compare with unidirectional descending analog broadcasting, the interaction feature of digital broadcasting has produced great change.

Be the ability of the comprehensive and collaborative work that guarantees digital broadcasting, at first necessary introduction standard.At present the broadcasting method of the Digital Terrestrial Television Broadcast of recommending is to use the U.S. ATSC (Advanced Television Systems Committee) of 8-VSB (residual sideband) and based on the DVB-T (digital video broadcast-terrestrial) in Europe of COFDM (OFDM of coding).

Since digital broadcasting must the compressed signal source sending mass data, so a few errors that occurs in passage is sizable to the influence of whole system.Therefore, need to reduce the mistake that appears in the passage.For reducing mistake, can increase transmitted power to increase signal to noise ratio (snr).But this can bring the problem that the caused cost of highoutput increases and interchannel disturbs such as big transmitted power and dispensing device.In order to alleviate these problems, digit broadcasting system uses can error correction and do not increase the error correcting code of electrical power, and error correcting code can be corrected the mistake that produces in the passage, and does not increase transmitted power, reduces the possibility that goes wrong in receiving.

Error correcting code is divided into automatic repeat request (ARQ) and forward error correction (FEC) two classes substantially.Based on ARQ, if detect mistake in receiver, then receiver sends the signal of request repeat data to transmitter.So transmitter is retransmitted this data.Because ARQ need allow receiver to send the backward channel of re-send request may signal to transmitter, so this method is not suitable for using in digital broadcasting.Simultaneously, based on FEC, the diacritic of signal on appending to this signal is sent out, and makes the mistake of receiver in can sense channel, with algebraic method mistake corrected then.

FEC is divided into two kinds of block code and convolution codes substantially.Block code is the linear block code, and is the code that satisfies cyclic code.Block code comprises BCH code and Rui De-Solomon code of expanding as the nonbinary of BCH code.The additional predetermined parity check symbol that is used for the reception data are carried out error correction of block code, and it has very strong correction burst error ability.

Simultaneously, for convolution code, it can come coded data based on the correlation between current input and the last input, and therefore the correction to random error is effective.Usually Viterbi decoder is used for convolution code is decoded.

Fig. 1 is the block diagram according to the dispensing device of the digit broadcasting system of the DVB-T of COFDM.

With reference to Fig. 1, the dispensing device of digit broadcasting system comprises first scrambler 10 and second scrambler 12, forward error correction (FEC) unit 20 and modulating unit 30.FEC unit 20 comprises Yi Rui De-Saloman (RS) encoder 21 and Er Rui De-Saloman (RS) encoder 25, first external interleaver 22 and second external interleaver 26, first convolution coder 23 and second convolution coder 27 and interleaver 24.Modulating unit 30 comprises pilot tone/system information insertion piece 31, mapping/OFDM modulator block 33, protection (GI) insertion piece 35, digital simulation (D/A) conversion block 37 and radio frequency (RF) piece 39 at interval.

In the DVB-T method, this method is supported the Delamination Transmission pattern.In this case, the separator (not shown) is divided into high priority (HP) layer and low priority (LP) layer with the transport stream (TS stream) of input.A TS stream that sends by the HP layer is imported into first scrambler 10, and the 2nd TS stream that sends by the LP layer is imported into second scrambler 12 simultaneously.

First scrambler 10 and second scrambler 12 carry out randomization according to preassigned pattern to the data value that the first and second input TS flow.At receiver end to this processing execution inverse process to recover original value.

The mistake that the 20 pairs of data after first scrambler 10 and 12 randomizations of second scrambler in FEC unit are encoded and occurred in the data transmission to be corrected in.That is, a RS encoder 21 and the 2nd RS encoder 25 receive the data from first scrambler 10 and second scrambler 12 respectively, and these data are carried out the RS coding so that error correction with block mode.The additional parity check code (detected symbol) that is used for error correction of RS coding.The quantity of the parity check code that is added depends on transmitting system.In the DVB-T method, 16 parity check symbols are appended in the TS stream of each 188 byte, therefore, the total bytes after the error correction coding is 204.

First external interleaver 22 and second external interleaver 26 interweave with block mode execution RS coded data to a RS encoder 21 and the 2nd RS encoder 25 respectively, break up potential burst error thus.First convolution coder 23 and second convolution coder 27 are carried out convolutional encoding to the data that interweaved by first external interleaver 22 and second external interleaver 26 respectively.The DVB-T method usually use have that limited length is 7, code check is 1/2 convolution code.First convolution coder 23 and second convolution coder 27 carry out convolution encoded data and are interweaved with output by interleaver 24 again.

To the coded data of 20 outputs from the FEC unit, modulating unit 30 is carried out the digital modulation of the sending method that is suitable for adopting in the digit broadcasting system.As shown in Figure 1, use in the situation of OFDM in the DVB-T system, mapping/OFDM modulator block 33 will become the symbol such as QPSK (Quadrature Phase Shift Keying), 16-QAM (quadrature amplitude modulation) and 64-QAM from the data map of interleaver 24 outputs, and use IFFT (invert fast fourier transformation) to carry out the OFDM modulation.In this process, pilot tone/system information is inserted piece 31 and will be used for signal Synchronization and passage estimated pilot signal and be inserted into this signal about the information of transmission mode.GI inserts the GI that piece 35 inserts the ISI (intersymbol interference) that is used for preventing multi-path environment.37 pairs of D/A conversion blocks have inserted the signal combine digital of GI to simulation (D/A) conversion.RF piece 39 will be amplified to high frequency through the signal of D/A conversion, and by this signal of antenna transmission.

As mentioned above, the dispensing device of traditional digit broadcasting system mainly adopts the concatenated code system, this concatenated code system uses a RS encoder 21 and second encoder 25 as outer encoder, uses first convolution coder 23 and second convolution coder 27 as inner encoder.And, in situation about supporting such as the dispensing device of the digit broadcasting system of the Delamination Transmission pattern of DVB-T, its encoder that adopts uses the error correction/encoding method with identical parameters at HP and LP layer, and its interleaver that adopts interweaves with identical method execution.

As mentioned above, the encoder and the interleaver that have identical parameters in use are used for carrying out having following advantage under the situation of error correction coding at HP and LP layer, and promptly all data that send from HP layer and LP layer receiver that can be had a same structure receives.

But, may there be such situation, promptly in different separately communication environments, there are receiver that uses the HP layer and the receiver that uses the LP layer.In this case, the environment according to receiver uses different error correcting codes can increase the transmitting efficiency of whole system.For example, the receiver under mobile communication environment requires to have receptivity preferably, and the receiver in the fixed communication environment requires to receive more substantial signal.In this case, for the data that send by any one deck, must carry out more effective error correction coding to strengthen the receptivity of receiver.For data, must carry out different error correction codings to have higher data transfer rates by another layer transmission.Therefore, the dispensing device of digit broadcasting system need be carried out different error correction coding processing to the different channel environment of receiver.

Summary of the invention

The purpose that the present invention made a search is to solve the aforementioned problems in the prior.Therefore, the purpose of this invention is to provide a kind of dispensing device and method of digit broadcasting system, can consider the communication environment of receiver, the data that send by the HP layer are carried out different codings with the data that send by the LP layer, so that carry out error correction.

Above-mentioned purpose of the present invention is to realize by the dispensing device that a kind of digit broadcasting system is provided.This dispensing device comprises: Rui De-Saloman (RS) encoder is used for first input transport stream (TS) stream is carried out the RS coding; The BPC encoder is used to use the BPC sign indicating number that the 2nd TS stream of input is carried out coding so that carry out error correction; First and second external interleavers are used for respectively to being interweaved by the data of RS encoder encodes and the data of BPC encoder encodes; First and second inner encoders are used for respectively the data that interweaved by first and second external interleavers being carried out convolutional encoding; Interleaver is used for the first and second inner encoder coded datas are interweaved; And modulating unit, the data that are used for interleaver is interweaved are carried out digital modulation, and send this modulating data.

The BPC encoder comprises: first encoder is used for coding TS stream, so that carry out error correction; Interleaver is used for the data of first encoder encodes are interweaved; And second encoder, be used for the data that interleaver interweaves are encoded, so that carry out error correction.And first and second encoder be to use Rui De-Saloman (RS) encoder of Rui De-Solomon code or use the Bose-Chaudhuri-Hocquenghem Code device of BCH code.

Interleaver can also comprise: first interleaver is used for the first inner encoder coded data is interweaved; Second interleaver is used for the second inner encoder coded data is interweaved, and wherein, modulating unit carries out digital modulation to the data that interweaved by first interleaver and second interleaver, and sends this modulating data.

First and second interleavers can use identical method that the first inner encoder coded data and the second inner encoder coded data are interweaved.First and second interleavers also can use diverse ways that the first inner encoder coded data and the second inner encoder coded data are interweaved.

Best described modulating unit is modulated according to OFDM (OFDM) combine digital.In this case: modulating unit comprises: mapping/OFDM modulator block is used for by mapping method the data that interleaver interweaves being shone upon, and carries out the OFDM modulation; Pilot tone/system information is inserted piece, is provided for the information of signal Synchronization and passage estimated pilot signal and relevant sending mode to mapping/OFDM modulator block; Piece is inserted in protection (GI) at interval, is used for inserting GI to the signal from the output of mapping/OFDM modulator block; Digital simulation (D/A) conversion block is used for the signal that has inserted GI is carried out the D/A conversion; And radio frequency (RF) piece, be used for the conversion of signals through the D/A conversion is become high-frequency signal, and send this signal.

Preferably the dispensing device of digit broadcasting system also comprises: first and second scramblers are used for respectively the first and second TS streams being carried out randomization, and will offer RS encoder and BPC encoder through the randomized first and second TS streams.

Simultaneously, a kind of sending method of digit broadcasting system comprises step: (a) in the encoder of Rui De-Saloman (RS), (TS) stream is transmitted in first of input carry out the RS coding, and the output first coding data; (b) in the BPC encoder, use the BPC sign indicating number that the 2nd TS stream is carried out the BPC coding, so that carry out error correction, and export second coded data; (c) in first and second external interleavers, respectively first and second coded datas are interweaved, and export first and second interleaving datas; (d) in first and second inner encoders, respectively first and second interleaving datas are encoded; (e) in interleaver, interweave to carrying out once more respectively through the first and second inner encoder coded datas; And (f) in modulating unit, the data that interweave are once more carried out digital modulation, and send result data.

Preferably step (b) may further comprise the steps: (b1) coding the one TS stream, so that carry out error correction; (b2) coded data that obtains in step (b1) is interweaved; And (b3) to encoding once more, so that error correction at the interleaving data of step (b2) acquisition.Step (b1) and (b3) can use Rui De-Saloman (RS) sign indicating number or BCH code to encode.

Step (e) can also may further comprise the steps: (e1) in first interleaver, interweave to carrying out once more from the coded data of first inner encoder output; (e2) in second interleaver, interweave to carrying out once more from the coded data of second inner encoder output, wherein, the data of exporting from first and second interleavers that interweave are once more carried out digital modulation, and send the data of gained.

Step (e1) and (e2) can use same procedure respectively the coded data from first and second inner encoders output to be interweaved.Step (e1) and (e2) also can use distinct methods respectively the coded data from first and second inner encoders output to be interweaved.

Preferably step (f) uses OFDM (OFDM) to carry out digital modulation.In this case, step (f) may further comprise the steps: (f1) adopt a mapping method, and the data that mapping interweaves once more, and carry out the OFDM modulation; (f2) for be provided for the information of signal Synchronization and passage estimated pilot signal and relevant transmission mode in the data of (f1) step process; (f3) GI is inserted into from the signal of step (f1) output; (f4) signal that has inserted GI is carried out the D/A conversion; And (f5) will become high-frequency signal, and send this signal through the conversion of signals of D/A conversion.

The sending method of digit broadcasting system also comprises step: respectively the first and second TS streams are carried out randomization, and will offer step (a) and (b) through the randomized first and second TS streams.

Description of drawings

By with reference to the accompanying drawings the preferred embodiments of the present invention being described, above-mentioned and other purposes of the present invention and characteristics be will become apparent, wherein:

Fig. 1 is the block diagram of the dispensing device of general digit broadcasting system;

Fig. 2 is the block diagram according to the dispensing device of the digit broadcasting system of first embodiment of the invention;

Fig. 3 shows the flow chart of method of operation of dispensing device of the digit broadcasting system of Fig. 2;

Fig. 4 shows the block diagram of the BPC encoder of Fig. 2;

Fig. 5 is the data format schematic diagram that the BPC encoder by Fig. 2 is produced;

Fig. 6 is the block diagram according to the dispensing device of the digit broadcasting system of second embodiment of the invention; And

Fig. 7 shows the flow chart of method of operation of dispensing device of the digit broadcasting system of Fig. 6.

Embodiment

Below, be described in more detail the present invention with reference to accompanying drawing.

Fig. 2 is the block diagram according to the dispensing device of the digit broadcasting system of the first embodiment of the present invention.

With reference to Fig. 2, comprise first scrambler 110 and second scrambler 120, forward error correction (FEC) unit 200 and modulating unit 300 substantially according to the dispensing device of sending out of the digit broadcasting system of first embodiment.FEC unit 200 comprises Rui De-Saloman (RS) encoder 210, the long-pending sign indicating number of piece (Block Product Code) (BPC) encoder 250, first external interleaver 220 and second external interleaver 260, first convolution coder 230 and second convolution coder 270 and interleaver 240.Modulating unit 300 comprises pilot tone/system information insertion piece 310, mapping/OFDM modulator block 330, protection (GI) insertion piece 350, digital simulation (D/A) conversion block 370 and radio frequency (RF) piece 390 at interval.

According to first embodiment, the dispensing device of digit broadcasting system is supported the Delamination Transmission pattern, and therefore, the separator (not shown) is divided into high priority (HP) layer and low priority (LP) layer with the transport stream (TS stream) of input.A TS stream that sends by the HP layer is imported into first scrambler 110, and the 2nd TS stream that sends by the LP layer is imported into second scrambler 120 simultaneously.

First scrambler 110 and second scrambler 120 carry out randomization to the data value of the first and second input TS streams respectively according to preassigned pattern.This is the problem for the system synchronization that prevents loss, this problem is because in the synchrodata process of transmitting and since such as 00000000b or 11111111b repeating data caused.At receiver end to this processing execution inverse process to recover original value.

The 200 pairs of mistakes of encoding and occurring in the data transmission in FEC unit to be corrected in through the data of

first scrambler

110 and 120 inputs of second scrambler.

That is, RS encoder 210 receives from the data of first scrambler, 110 outputs, and these data are carried out the RS coding with block mode so that error correction, and BPC encoder 250 receives from the data of second scrambler, 120 outputs simultaneously, and these data are carried out the BPC coding.260 pairs of first external interleaver 220 and second external interleavers are carried out respectively from the data of RS encoder 210 outputs with from the data of BPC encoder 250 outputs and are interweaved.First convolution coder 230 and second convolution coder 270 are respectively to carrying out convolutional encoding from the data of first

external interleaver

220 and 260 outputs of second external interleaver.

First convolution coder 230 and second convolution coder, 270 coded datas are interweaved to output to modulating unit 300 by interleaver 240 again.Interleaver 240 can be made up of position interleaver and symbol interleaver.The position interleaver is carried out in the position mode and is interweaved.In the OFDM method, symbol interleaver interweaves to the available subcarrier that exists in the OFDM symbol.

To the coded data from interleaver 240 outputs, modulating unit 300 is carried out the digital modulation that is suitable for the sending method in the digit broadcasting system.Mode by way of example, Fig. 2 shows the DVB-T system of execution based on the modulation of OFDM.

In this case, the mapping of modulating unit 300/OFDM modulator block 330 is with the symbol of data map one-tenth such as QPSK (Quadrature Phase Shift Keying), 16-QAM (quadrature amplitude modulation) and the 64-QAM of interleaver 240 outputs, and use IFFT (invert fast fourier transformation) carries out the OFDM modulation.In this process, pilot tone/system information is inserted piece 310 and is inserted and be used for signal Synchronization and passage estimated pilot signal and about the information of transmission mode.GI inserts the protection interval (GI) that piece 350 inserts the intersymbol interference (ISI) that is used for preventing multi-path environment.And 370 pairs of D/A conversion blocks have inserted the signal combine digital of GI to simulation (D/A) conversion.RF piece 390 will be amplified to high frequency through the signal of D/A conversion, and by this signal of antenna transmission.

Fig. 3 shows the flow chart of the method for operation of dispensing device according to digit broadcasting system of the present invention shown in Figure 2.

With reference to this flow chart, the separator (not shown) is divided into TS stream that sends by high priority (HP) layer and the 2nd TS stream (S700) that sends by low priority (LP) layer with the transport stream (TS stream) of input.The TS stream that separator separates is input to first scrambler 110, and first scrambler 110 is carried out the scrambling operation with randomization the one TS stream (S702 and S704).Multiplexedly be used to produce comprehensive bit-rows, so that send video, audio frequency and the data line of compression separately.Program stream is the multiplex mode that is used for the medium such as having the CD-ROM that lacks mistake and loss of data relatively.TS stream is the multiplex mode that is used for the environment such as the noisy communication channel that may send very much mistake or loss of data.A grouping of multiplexed row has the fixed size of 188 bytes.

RS encoder 210 is carried out the RS coding so that error correction (S706) with block mode to the data of first scrambler, 110 scramblings.

According to the RS coding, a piece of being made up of k incoming symbol is encoded into the piece with n code sign, and wherein n is greater than k.Therefore, added n-k the redundant symbol that is called as Rui De-Saloman parity check code.The quantity of the parity check code that adds by RS coding depends on transmitting system, and for example, the symbol of per 188 bytes adds 16 or 20 parity check codes.The RS decoder uses parity check code that the data that received are checked.If the check result explanation detects mistake, the position of RS-decoder searches mistake, the data of correcting distortion are also recovered original symbol.Usually, quantity is at most half mistake of the parity check code that added and is repaired, and can not correct quantity and surpass half mistake of parity check number of codes.

First external interleaver 220 is carried out the outer operation (S708) that interweaves by block mode to RS encoder 210 coded datas.In the performed various deinterleaving methods of first external interleaver 220, use convolutional deinterleaver usually.Convolutional deinterleaver is written in the symbol or the position of input among of shift register of predetermined quantity in one-period, and the symbol that read shift register interweaves with output thus in one-period.The basic function of interleaver is farthest to break up burst error.

230 pairs of data from 220 outputs of first external interleaver of first convolution coder are carried out convolutional encoding (S710).Convolutional encoding is used for each row of the continuous line of input of k position is encoded into n carry-out bit, and coding is made of the convolution that input position and binary pulse respond.The sending method of DVB-T transmitting system is used convolutional coding method, and its encoder has limited length 7 and encoding rate 1/2.In this, the encoding rate of convolution coder 230 can change, for example, and 2/3,3/4,5/6 and 7/8.

240 pairs of processes of interleaver convolution coder, 230 convolution encoded data are carried out and are interweaved (S722), have improved the mis-behave that is caused by multipath thus.For aforesaid coded data, modulating unit 300 is carried out and is suitable for the digital modulation that data send, and sends these data (S730).

Simultaneously, the 2nd TS stream that is separated by separator and send through the LP layer is imported into second scrambler 120, and by its scrambling (S174).The data of scrambling are carried out BPC-coding (S716) by BPC encoder 250.

BPC encoder 250 can constitute by the whole bag of tricks, and one of them example is illustrated among Fig. 4.As shown in Figure 4, BPC encoder 250 comprises first encoder 252, interleaver 254 and second encoder 256.First encoder 252 and second encoder 256 can use the RS encoder.In using the situation of RS encoder as first encoder 252 and second encoder 256,252 pairs of inputs of first encoder data are carried out the RS coding, add predetermined parity check code thus.Interleaver 254 interweaves to first encoder, 252 coded datas by block mode, breaks up potential burst error thus.The data of 256 pairs of interleavers of second encoder, 254 outputs are carried out the RS coding.

Fig. 5 shows the example of the data format of BPC encoder shown in Figure 4 250 generations.With reference to Fig. 5, for data, the parity check code rP with n1-k1 size is added on the data of line direction with k1*k2 piece size, the parity check code cP with n2-k2 size is added on the data of column direction.PP represents to be positioned at the parity check code relative with parity check code rP on the column direction or is positioned at the parity check code relative with parity check code cP on the line direction.

When first encoder 252 added to parity check code rP on the data, 254 pairs of these data of interleaver interweaved, and second encoder 256 adds parity check code cP and pP on the data to then.On the contrary, when first encoder 252 added to parity check code cP on the data, 254 pairs of these data of interleaver interweaved, and second encoder 256 adds parity check code rP and pP on the data to then.

For the data of above-mentioned error correction coding, receiver uses the BPC decoder to carry out decoding, and the BPC decoder comprises: two decoders, i.e. first decoder and second decoder; And the deinterleaver corresponding with dispensing device.In receiving data, occur since add on line direction that parity check code causes exceed mistake and can correct the mistake of scope the time, the situation of the first decoder error correcting capability has appearred exceeding, receiver produces the removing mark, replaces abandoning corresponding flow data.Then, after deinterleaving, comprise that the data of removing mark are sent to second decoder.Second decoder uses to be removed mark and corrects this mistake once more at the parity check code that column direction adds.In this case, be positioned at bit-error locations, carry out the twice of the ability of error correction so error correction capability is the parity check code that uses column direction to add separately owing to remove mark.Therefore, when the mistake of the error correcting capability that first decoder occurs exceeding, in second decoder, can correct this mistake.

As mentioned above, BPC encoder 250 can use and replace the Bose-Chaudhuri-Hocquenghem Code device RS encoder, the employing BCH code as first encoder 252 and second encoder 256.BCH code is disclosed in nineteen sixty in nineteen fifty-nine with by Bose and Chaudhure by Hocquenghen.The title of BCH code comes from the initial of these three people's names.BCH code is by will be to the multi-term expression of the symbolism of shifting left divided by a multi-term expression that generates and add that CRC (cyclic redundancy check (CRC) code) produces, and these are different with the Hamming code.BPC encoder 250 step-by-step modes are carried out calculating, and the RS encoder is carried out calculating by the symbol mode.

BPC encoder 250 coded datas are sent to second external interleaver 260.260 pairs of data that sent of external interleaver interweave, and break up the potential burst error (S718) that occurs in passage thus.

270 pairs of data that interweaved by second external interleaver 260 of second convolution coder are carried out convolutional encoding, are used for correction process (S720).Second convolution coder, 270 coded datas are sent to interleaver 240, and by interleaver 240 interweave once more (S722).For the coded data that is used for error correction, modulating unit 300 is carried out and is suitable for the digital modulation that data send, and by these data of antenna transmission (S730).

As mentioned above, can carry out different codings to carry out correction process with the data that send by the LP layer to the data that send by the HP layer.

Fig. 6 is the block diagram according to the dispensing device of the digit broadcasting system of second embodiment of the invention.

With reference to Fig. 6, the dispensing device of digit broadcasting system comprises first scrambler 410 and second scrambler 420, forward error correction (FEC) unit 500 and modulating unit 600.FEC unit 500 comprises Rui De-Saloman (RS) encoder 510, the long-pending sign indicating number of piece BPC encoder 550, first external interleaver 520 and second external interleaver 560, first convolution coder 530 and second convolution coder 570 and first interleaver 540 and second interleaver 580.Modulating unit 600 comprises pilot tone/system information insertion piece 610, mapping/OFDM modulator block 630, protection (GI) insertion piece 650, digital simulation (D/A) conversion block 670 and radio frequency (RF) piece 690 at interval.

Is two interleaver parts according to the dispensing device of the broadcast system of second embodiment with the dispensing device difference that is the broadcast system of first embodiment shown in Figure 2, promptly uses first interleaver 540 and second interleaver 580.Therefore, interweaved by diverse ways individually by first convolution coder 530 and second convolution coder, 570 coded datas.The function of other each piece is identical with first embodiment's shown in Figure 2.

With reference to Fig. 6, the sending method difference of the sending method of second embodiment and Fig. 3 is to be interweaved (S810 and S812) by first interleaver 540 from the data of first convolution coder 530 output, and from the data of second convolution coder, 570 outputs by second interleaver 580 interweave (S820 and S822).That is, according to second embodiment, the data of being exported by first convolution coder 530 and second convolution coder 570 are interweaved by diverse ways individually.Other step is identical with Fig. 3.

As mentioned above, use the outer encoder of different parameters,, distribute different error correcting codes, and carry out different interleaving treatment data that send by the HP layer and the data that send by the LP layer according to the dispensing device of digit broadcasting system of the present invention.Therefore, owing to data are carried out different codings,, send effectively so can be adapted to the communication environment of receiver so that carry out error correction according to transport layer.

And by way of example, the foregoing description uses the OFDM of DVB-T system as modulator approach, but it is not a limitation of the present invention.The present invention can be applied to the dispensing device of different digit broadcasting systems, and no matter employed modulator approach how, and can provide the data of the optimum of the communication environment that is suitable for receiver to send.

As mentioned above,, carry out different error correction codings and handle, therefore can be suitable for the error correction coding processing of receiver communication environment for by the data of HP layer transmission and the data that send by the LP layer.And, by using optimum error correcting code, can improve the efficient of the data transmission of whole system according to the communication environment of receiver.

The foregoing description and advantage only are exemplary illustrated, are not intended to limit the invention.The principle of this specification can easily be applied to the device of other type.Specification of the present invention attempts to describe rather than limit the scope of claims.To those skilled in the art, many changes, modifications and variations all are conspicuous.In claims, the explanation of device adding method attempts to cover structure as described herein, and structural equivalence and the equivalent construction of carrying out described function.

Claims

1. the dispensing device of a digit broadcasting system comprises:

Rui De-Saloman (RS) encoder is used for first input transport stream (TS) stream is carried out the RS coding;

The BPC encoder is used to use the BPC sign indicating number that the 2nd TS stream of input is carried out coding so that carry out error correction;

First and second external interleavers are used for respectively to being interweaved by the data of RS encoder encodes and the data of BPC encoder encodes;

First and second inner encoders are used for respectively the data that interweaved by first and second external interleavers being carried out convolutional encoding;

Interleaver is used for the first and second inner encoder coded datas are interweaved; And

Modulating unit, the data that are used for interleaver is interweaved are carried out digital modulation, and send this modulating data.