CN1245834C

CN1245834C - Digital broadcasting transmitter for different error correcting code by communication environment and method thereof

Info

Publication number: CN1245834C
Application number: CN 03108491
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: 2003-04-14
Publication date: 2006-03-15
Anticipated expiration: 2023-04-14
Also published as: CN1491033A

Abstract

A transmission device of a digital broadcasting system differentiating ECC(Error Correction Coding) processes according to communication environment is provided to perform ECC processes for data transmitted through an HP(High Priority) layer and data transmitted through LP(Low Priority) layer by using different encoders and interleavers, thereby differentiating the ECC processes. An RS encoder(210) RS-encodes the first TS(Transport Stream). A BPC(Block Product Code) encoder(250) BPC-encodes the second TS. The first and second outer interleavers(220,260) re-array data encoded in the RS encoder(210) and data encoded in the BPC encoder(250), respectively. A convolution encoder(230) convolution-encodes the data re-arrayed in the first outer interleaver(220). A TCM(Trellis Coded Modulation) encoder(270) TCM-encodes the data re-arrayed in the second outer interleaver(260). An inner interleaver(240) re-arrays the encoded data, respectively. A modulator portion(300) digitally modulates the re-arrayed data, and transmits the modulated data.

Description

The digital broadcast transmission device of different error correcting code by communication environment and method

Technical field

The present invention relates to have the dispensing device and the method thereof of the digit broadcasting system of handling according to the different error correction codings of communication environment, be specifically related to support the dispensing device and the method thereof of the digit broadcasting system of layering sending mode, described dispensing device can according to send level differently coded data be used for error correction.

Background technology

Digit broadcasting system is used for the digital coding broadcast singal, sends signal and pass through the receiving system received signal to satellite and terrestrial channel.Compare with analog broadcasting, digital broadcasting is owing to having used digital encoding system to have the advantage of the system integration and interoperability.In addition, the interactive features of digital broadcasting has greatly changed monolateral analog broadcasting.

In order to guarantee the integrated and interoperability of digital broadcasting, at first, need the introducing standard.The broadcasting method that is used for Digital Terrestrial Television Broadcast of current proposition is the ATSC that utilizes 8-VSB (residual sideband) (Advanced Television Systems Committee) of the U.S. and the DVB-T based on COFDM (Coded Orthogonal Frequency Division Multiplexing (COFDM)) (digital video broadcasting-ground) in Europe.Except these, various broadcasting methods have been proposed recently, for example, based on the DMB-T (ground digital multimedia TV broad cast) of TDS-OFDM (time-domain synchronization OFDM), from the next ADTB-T (advanced digital television broadcasting-ground) of VSB improvement, from the next SMCC (synchronous multicarrier CDMA) of COFDM improvement, CDTB-T (China Digital TV broadcasting-ground) and BDB-T.

Because digital broadcasting needs the compressed signal source to send lot of data, some mistakes in channel influence whole system considerably.Therefore, need to reduce the mistake that in channel, takes place.In order to reduce errors, can improve transmitted power to improve signal noise ratio (SNR).But it has such as such problem, i.e. the cost of the raising that is caused by the interference of output of the height of bigger transmitted power and dispensing device and interchannel.In order to alleviate these problems, digit broadcasting system uses error correcting code, and it makes mistake to be repaired and does not need to improve transmitted power.

Error correcting code mainly is divided into automatic repetitive requests (ARQ) and forward error correction (FEC).According to ARQ, if detect mistake in receiver, then receiver sends the signal that is used for the request repeat data to transmitter.Therefore, transmitter retransmission data.Because ARQ needs one to be used to allow the Return Channel of receiver to transmitter transmission re-send request may signal, so this method is not suitable for using in digital broadcasting.And according to FEC, signal is sent out with the additional code element that is added to signal, so that receiver can detect the mistake in channel and with algebraic method it be corrected subsequently.

FEC mainly is divided into block code and convolution code.Block code is linear block code and the condition that satisfies cyclic code.Such block code comprises BCH code and as RS (Reed-Solomon) sign indicating number of the expansion of the nonbinary code of BCH code.Block code has added predetermined parity symbols with the correction mistake to information data, and superior aspect correction burst error.

And for convolution code, it carries out the coding based on the correlation between current input and input in the past, and is therefore effective aspect the correction random error.

Be sent out because be used for the additional information of coded data on being added to the data that are used for error correction of error correction, therefore reduced the amount of information that each bandwidth can send.Therefore according to the sending method of recent research, for example, TCM (Trellis-coded modulation), coding and modulation function are combined into one, can obtain big coding advantage and do not reduce data transfer rates or improve bandwidth.

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

Referring to Fig. 1, the dispensing device of digit broadcasting system comprises first and second scramblers 10 and 12, forward error correction (FEC) unit 20 and modulating unit 30.FEC unit 20 comprises first and second Reed-Solomons (RS) encoder 21 and 25, first and second outer interleaver 22 and 26, first and second convolution coders 23 and 27 and inner interleaver 24.Modulating unit 30 comprises pilot tone/system information insertion piece 31, mapping/OFDM modulator block 33, protection (GI) insertion piece 35, digital-to-analogue (D/A) conversion block 37 and radio frequency (RF) piece 39 at interval.

Under the situation of DVB-T method, it supports the layering sending mode.Under this situation, transmission stream (TS stream) separated device (not shown) of being imported is divided into high priority (HP) level and low priority (LP) level.A TS stream that sends by the HP level is imported into first scrambler 10, and the 2nd TS stream that sends by the LP level is imported into second scrambler 12.

The data value randomization of first and second TS stream that first and second scramblers 10 and 12 will be imported in predetermined patterns.This is handled at receiver and is reversed execution so that the reduction original value.

FEC unit 20 is for carrying out coding by first and second scramblers 10 and 12 randomized data, so that be corrected in the mistake that takes place during data send.That is, the first and second RS encoders 21 and 25 receive data from first and second scramblers 10 and 12, and the data block-by-block is carried out the RS coding with error correction.The RS coding adds that parity check (detected symbol) is with error correction.The quantity of the parity check code that is added depends on the method for transmission.Under the situation of DVB-T method, 16 parity symbols are added to each TS stream of 188 bytes, thus the byte of error correction coding add up to 204.

First and second outer interleaver 22 and 26 interweave at the first and second RS encoders 21 and 25 block-by-blocks by the RS coded data, have therefore disperseed possible burst error.First and second convolution coders 23 and 27 are carried out convolutional encoding for the data that interweave in first and second outer interleaver 22 and 26.The general use of DVB-T method has the convolution code of constraint length 7 and encoding rate 1/2.Convolution encoded data in first and second convolution coders 23 and 27 is interweaved with output again by inner interleaver 24.

For 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 using in digit broadcasting system.As shown in Figure 1, under the situation of the OFDM that uses the DVB-T system, mapping/OFDM modulator block 33 is a code element such as QPSK (quadriphase PSK), 16-QAM (quadrature amplitude modulation) and 64-QAM with data map, and utilizes IFFT (contrary fast fourier transform) to carry out the OFDM modulation.In this process, pilot tone/system information is inserted piece 31 and is inserted to signal and be used for signal Synchronization and channel estimating and about the pilot signal of the information of sending mode.GI inserts piece 35 and inserts the GI that is used for the ISI (inter symbol interference) that prevents at multi-path environment.D/A conversion block 37 is carried out digital-to-analogue (D/A) conversion for the signal that inserts GI.RF piece 39 amplifies the signal of D/A conversion with high frequency, and via the antenna transmission signal.

As mentioned above, the dispensing device of traditional digit broadcasting system mainly uses the cascaded code system, and described system uses the first and second RS encoders 21 and 25 as external encoder, uses first and second convolution coders 23 and 27 as internal encoder.

Equally, for the dispensing device of supporting such as the digit broadcasting system of the Delamination Transmission pattern of DVB-T, its uses for HP has the encoder of same size with the LP level and carries out the interleaver that interweaves with identical method.As mentioned above, using for HP and LP level under the encoder of same procedure and the situation that interleaver is used to error correction coding, has an advantage, promptly all can be by the receiver reception with same structure at HP and LP level coded data.

But, may there be a kind of situation, use the receiver of HP level to be present under the different separately communication environments with the receiver that uses the LP level.In this case, use the transmitting efficiency that can improve whole system according to the difference of the error correction coding of the environment of receiver.For example, the receiver under mobile communication environment need receive the strong relatively signal of receptivity, and the receiver under the fixed communication environment need be received in strong signal aspect the rapid data transmission.In this case, in any one level by the data of error correction coding, need to carry out the error correction coding that more strengthens to improve the receptivity of receiver.For data, need to carry out different error correction codings to have more data transmission rate in other level error correction codings.Therefore, the dispensing device of digit broadcasting system need be carried out different error correction coding processing for the different channels environment of receiver.

Summary of the invention

In order to solve the problems referred to above in prior art field, the present invention obtains exploitation.Therefore, an object of the present invention is to provide a kind of dispensing device and method thereof of digit broadcasting system, can differently encode by the data of HP level transmission and the data that send by the LP level, so that error correction according to the communication environment of receiver.

The acquisition of above-mentioned purpose is by a kind of dispensing device of digit broadcasting system is provided, the transmission stream (TS) that it will be imported is divided into TS stream and the 2nd TS stream, and first and second TS stream of encoding respectively is with error correction, comprise: Reed-Solomon (RS) encoder is used for carrying out the RS coding for TS stream; Piece product code (BPC) encoder is used for carrying out the BPC coding for the 2nd TS stream; First and second outer interleaver are used for interweaving respectively from the data of RS encoder output and the data of exporting from the BPC encoder; Convolution coder is used for carrying out convolutional encoding for the data that interweaved by first outer interleaver; The TURBO encoder is used for carrying out the TURBO coding for the data that interweaved by second outer interleaver; Inner interleaver is used to interweave by the convolution coder coded data with by the data of TURBO encoder encodes; And modulating unit, be used for digital modulation by inner interleaver data that interweave and the data that send modulation.

Preferably, the BPC encoder comprises: first encoder is used for coding TS stream with error correction; Interleaver, data by first encoder encodes are used to interweave; Second encoder, the data that interweaved by interleaver of being used to encode are with error correction.First and second encoders are Bose-Chaudhuri-Hocquenghem Code devices.

Preferably, described TURBO encoder utilizes TURBO-TCM sign indicating number or TURBO sign indicating number to carry out error correction.

Inner interleaver interweaves by the convolution coder coded data with by the data of TURBO encoder encodes with identical method.Inner interleaver also interweaves by the convolution coder coded data with by the data of TURBO encoder encodes with diverse ways.

Preferably, modulating unit utilizes OFDM (OFDM) modulation to come the combine digital modulation.Modulating unit comprises: mapping/OFDM modulator block is used for shining upon the data that interweaved by inner interleaver and carrying out the OFDM modulation with a kind of mapping method; System information is inserted piece, is used to mapping/OFDM modulator block to be provided for the pilot signal of signal Synchronization and channel estimating and about the information of sending mode; Piece is inserted in protection (GI) at interval, is used for inserting a GI to the signal from the output of mapping/OFDM modulator block; Digital-to-analogue (D/A) conversion block is used for the signal that inserts GI is carried out the D/A conversion; Radio frequency (RF) piece is used for the conversion of signals of D/A conversion is high-frequency signal and sends this signal.

Preferably, described dispensing device also comprises: first and second scramblers are used for respectively first and second TS being flowed randomization to provide first and second TS stream to RS encoder and BPC encoder.

And, flow in the sending method with the digit broadcasting system of error correction input transfer stream (TS) being divided into TS stream and the 2nd TS stream and first and second TS that encode respectively, described sending method comprises step: (a) carry out Reed-Solomon (RS) coding with error correction for TS stream, and the output first coding data; (b) encode with error correction for the 2nd TS stream execution block product code (BPC), and export second coded data; (c) interweave respectively first and second coded datas and output first and second interleaving datas; (d) carry out convolutional encoding for first interleaving data; (e) carry out the TURBO coding for second interleaving data; (f) interweave again by the convolution coder coded data with by the data of TURBO encoder encodes; And data that (g) interweave again with high-frequency digital modulation and send modulated data.

Preferably, step (b) comprises step: the TS stream of encoding for the first time is with error correction; The data of interweaving encoding; The data of code interleaving are with error correction for the second time.First and second coding steps utilize the BCH code coded data.

Described TURBO coding step utilizes TURBO-TCM sign indicating number or TURBO sign indicating number to carry out error correction.

Step (f) is with identical method interweave convolution encoded data and TURBO coded data.Step (f) is also with diverse ways interweave convolution encoded data and TURBO coded data.

Preferably, step (g) is utilized the modulation of OFDM (OFDM) modulation combine digital.Step (g) comprising: (g1) shine upon the data that interweave again and carry out the OFDM modulation with mapping method; (g2) be provided for the pilot signal of signal Synchronization and channel estimating and about the information of sending mode to mapping/OFDM modulation step; (g3) insert GI to signal from step (g1) output; (g4) carry out the D/A conversion for the signal that inserts GI; And the conversion of signals of (g5) D/A being changed is high-frequency signal and sends this signal.

Preferably, sending method also comprises step: randomization first and second TS stream is to provide first and second TS stream to step (a) respectively.

Description of drawings

By reference description of drawings the preferred embodiments of the present invention, above-mentioned purpose of the present invention and characteristics will become apparent, wherein:

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

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

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

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

Fig. 5 is the view that the data format that the BPC encoder of Fig. 2 sets up is shown;

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

Fig. 7 is the flow chart of operation method 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 that illustrates according to the dispensing device of the digit broadcasting system of the first embodiment of the present invention.

Referring to Fig. 2, mainly comprise first and

second scramblers

110 and 120, forward error correction (FEC) unit 200 and modulating unit 300 according to the dispensing device of the digit broadcasting system of first embodiment.FEC unit 200 comprises Reed-Solomon (RS) encoder 210, piece product code (BPC) encoder 250, first and second

outer interleaver

220 and 260, convolution coder 230, TURBO encoder 270 and inner interleaver 240.Modulating unit 300 comprises pilot tone/system information insertion piece 310, mapping/OFDM modulator block 330, protection (GI) insertion piece 350, digital-to-analogue (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 layering sending mode, and therefore will transmit stream (TS stream) by the separator (not shown) is divided into high priority (HP) level and low priority (LP) level.A TS stream that sends by HP priority is imported into first scrambler 110, and the 2nd TS stream that sends by the LP level is imported into second scrambler 120.

First and

second scramblers

110 and 120 are the data value of first and second TS stream of randomization input in predetermined patterns.This is in order to prevent during synchrodata sends owing to cause the synchronous problem of the system of losing such as the repetition numeral of 00000000b or 11111111b.This is handled at receiver and is reversed execution with the reduction raw value.

The 200 pairs of data by first and

second scramblers

110 and 120 inputs in FEC unit are carried out coding, to be corrected in the mistake that takes place during data send.

That is, RS encoder 210 receives from the data of first scrambler, 110 outputs, and block-by-block carries out the RS coding for data, and correcting mistake, and BPC encoder 250 receives from the data of second scrambler, 120 outputs, and data are carried out the BPC coding to correct mistake.First and second

outer interleaver

220 and 260 interweave to carrying out from the data of

RS encoder

210 and 250 outputs of BPC encoder with separately preordering method.

Convolution coder 230 is for the data execution convolutional encoding from 220 outputs of first outer interleaver, and TURBO encoder 270 utilizes TURBO sign indicating number or TURBO-TCM sign indicating number for carrying out coding from the data of second outer interleaver, 260 outputs.Convolution encoded data and TURBO or TURBO-TCM coded data are interweaved again by inner interleaver 240 and are output to modulating unit 300.Inner interleaver 240 can comprise a bit interleaver and a symbol interleaver.Described bit interleaver is carried out Bit Interleave to the input data.Under the situation of OFDM method, the spendable subcarrier that described symbol interleaver interweaves and exists in the OFDM code element.

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

In this case, the data map of the mapping of modulating unit 300/OFDM modulator block 330 interleaver 240 outputs internally is a code element such as QPSK (quadriphase PSK), 16-QAM (quadrature amplitude modulation) and 64-QAM, and utilizes IFFT (contrary fast fourier transform) to carry 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 channel estimating and about the pilot signal of the information of sending mode.GI inserts piece 350 and inserts the GI that is used for the ISI (inter symbol interference) that prevents at multi-path environment.In addition, D/A conversion block 370 is carried out digital-to-analogue (D/A) conversion for the signal that inserts GI.RF piece 390 amplifies the signal of D/A conversion with high frequency, and via the antenna transmission signal.

Fig. 3 is the flow chart that illustrates according to the operation method of the dispensing device of the digit broadcasting system of Fig. 2 of the present invention.

Referring to described flow chart, the transmission of input stream (TS) separated device (not shown) is divided into TS stream that will pass through the transmission of high priority (HP) level and the 2nd TS stream (S700) that sends by low priority (LP) level.A TS stream of being divided by separator is imported into first scrambler, 110, the first scramblers, 110 execution scramblers with randomization the one TS stream (S702 and S704).

RS encoder 210 is for carrying out the RS coding with error correction (S706) by the data block-by-block of first scrambler, 110 scramblers.According to the RS coding, comprise that a piece of k input symbols is encoded as the piece with n code symbols, wherein n is greater than k.Therefore, n-k redundancy symbol is coupled with, and this is called the Reed-Solomon parity check code.The quantity of the parity check code that is added by RS coding depends on transmitting system, for example the code element 16 or 20 of each 188 byte.The data that the RS decoder utilizes the parity check code inspection to be received.If detect a mistake as the result who checks, the position of RS decoder searches mistake then, the data and the raw symbol of reducing of correcting distortion.Generally, the mistake of half quantity of the parity check code that adds is repaired, and can not correct the mistake more than half quantity of parity check code.

First outer interleaver 220 is for carrying out outer interleaved (S708) at RS encoder 210 coded data block-by-blocks.In the whole bag of tricks of the interleaving data that passes through first outer interleaver 220, generally use convolutional deinterleaver.Described convolutional deinterleaver writes the code element or the bit of input at one of shift register of predetermined quantity in one-period, and in one-period read shift register so that therefore export a code element that interweaves.The basic function of interleaver is to disperse the mistake that happens suddenly to greatest extent.

Convolution coder 230 is for carrying out convolutional encoding (S710) from the data of first outer interleaver, 220 outputs.The line of input that convolution code is used for the k bit that each is continuous is encoded to the output bit of n number, and coding comprises the convolution of input bit and binary pulse response.The DVB-T transmitting system is used the convolution coder with constraint length 7 and encoding rate 1/2.At this, the encoding rate of convolution coder 230 can change, and for example 2/3,3/4,5/6 and 7/8.

Inner interleaver 240 interweaves (S722) for being carried out by convolution coder 230 convolution encoded data, has therefore improved the mis-behave that is caused by multipath.For the above-mentioned coded data that is used for error correction, modulating unit 300 is carried out and is suitable for the digital modulation of transfer of data and sends data (S730).

Simultaneously, that divide by separator and be imported into second scrambler 120 and by second scrambler, 120 scramblers (S714) by the 2nd TS stream that the LP level sends.By the data of scrambler by BPC encoder 250BPC coding (S716).

BPC encoder 250 can be constructed with the whole bag of tricks, and Fig. 4 shows its example.As shown in Figure 4, BPC encoder 250 comprises first encoder 252, interleaver 254 and second encoder 256.First and

second encoders

252 and 256 use RS encoder or Bose-Chaudhuri-Hocquenghem Code device.Using under the situation of RS encoder as first and

second encoders

252 and 256, first encoder 252 is carried out the RS coding for the data of input, has therefore added parity check code.Interleaver 254 interweaves by first encoder, 252 coded datas, has therefore disperseed possible burst error.Carried out the RS coding by the data that interleaver 254 interweaves once more by second encoder 256.

Fig. 5 illustrates the example of the data format of BPC encoder shown in Figure 4 250 foundation.Referring to Fig. 5, for the data of the block size with k1*k2, the parity check code rP with n1-k1 size is added to the data in line direction, and the parity check code cP with n2-k2 size is added to the data in column direction.PP is the parity check code on the column direction of being placed on for parity check code rP, or for the parity check code on the line direction of being placed on of parity check code cP.

When parity check code rP was added on the data by first encoder 252, data were interleaved device 254 and interweave, and parity check code cP and pP are added on the data by second encoder 256 then.On the contrary, when parity check code cP was added on the data by first encoder 252, data were interleaved device 254 and interweave, and parity check code rP and pP are added on the data by second encoder 256 then.

For being error correction and transmission coded data, receiver utilizes the BPC decoder to carry out decoding, and described BPC decoder comprises two decoders, i.e. first and second decoders and corresponding to the deinterleaver of dispensing device.When outside the error correcting capability of first decoder mistake taking place, receiver produces to be eliminated mark rather than abandons corresponding flow data.Comprise that by first decoder data of eliminating mark are deinterleaved, be sent to second decoder then.Second decoder utilization elimination mark and the parity check code that adds in column direction are corrected mistake again.In this case, owing to eliminate mark poor location wrong position, so error correcting capability is enhanced the twice when utilizing the parity check code error correction that is added to column direction separately.Therefore, when outside the error correcting capability of first decoder mistake takes place in, might be in the second decoder error correction.

As mentioned above, BPC encoder 250 can use the Bose-Chaudhuri-Hocquenghem Code device that utilizes BCH code rather than utilize the RS encoder as first and second encoders 252 and 256.BCH code is made public in nineteen sixty at nineteen fifty-nine and Bose and Chaudbure by Hocquengben.The title of BCH code is that the name prefix capitalization separately from these 3 people obtains.

The foundation of BCH code be by by the deconv of the symbolism that moves to left as Hamming code with the multinomial that produced and add CRC (CRC).Under the situation of using the Bose-Chaudhuri-Hocquenghem Code device, BPC encoder 250 calculates by turn, and the RS encoder calculates by code element.

Be sent to second outer interleaver 260 by BPC encoder 250 coded datas.Therefore the data that outer interleaver 260 interweaves and sent have disperseed the possible burst error (S718) that takes place in channel.

TURBO encoder 270 utilizes TURBO sign indicating number or TURBO-TCM sign indicating number to carry out the TURBO coding with error correction (S720) for the data that interweaved by second outer interleaver 260.

The TURBO sign indicating number is introduced by people such as Berrou.The TURBO encoder is generally parallel to be used two recursive system convolution (RSC) encoder and can have desired size according to its error correction capability.An interleaver is provided between two rsc encoders, and being used to interweave is input to the data of second rsc encoder, so that burst error is treated to random error.The TURBO sign indicating number can utilize iterative decoding and adjust desired bit error rate (BER) performance of size acquisition of interleaver.

TURBO addressable part 126 can use the TURBO-TCM sign indicating number to replace the TURBO sign indicating number.TCM (Trellis-coded modulation) can be by will encoding and modulation function is combined as one obtaining to encode greatly advantage, and need not reduce data transfer rates or improve bandwidth.The TURBO-TCM coding is carried out TCM function and TURBO encoding function simultaneously.

Be sent to inner interleaver 240 by TURBO encoder 270 coded datas.The data (S722) that inner interleaver 240 interweaves and sent.For the data that interweaved by inner interleaver 240, modulating unit 300 is carried out and is suitable for the digital modulation that data send, and via antenna transmission data (S730).

As mentioned above, might differently encode the data that send by the HP level and the data that send by the LP level with error correction.

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

Referring to Fig. 6, the dispensing device of digit broadcasting system comprises first and

second scramblers

410 and 420, forward error correction (FEC) unit 500 and modulating unit 600.FEC unit 500 comprises Reed-Solomon (RS) encoder 510, BPC encoder 550, first and second

outer interleaver

520 and 560, convolution coder 530, TURBO encoder 570 and first and second inner interleaver 540 and 580.Modulating unit 600 comprises pilot tone/system information insertion piece 610, mapping/OFDM modulator block 630, protection (GI) insertion piece 650, digital-to-analogue (D/A) conversion block 670 and radio frequency (RF) piece 690 at interval.

Dispensing device and different being of first embodiment shown in Figure 2 according to the broadcast system of the second embodiment of the present invention have used two inner interleaver, i.e. first and second inner interleaver 540 and 580.Therefore, interweaved respectively by diverse ways by convolution coder 530 coded datas with by TURBO encoder 570 coded datas.The function of other pieces is identical with first embodiment shown in Figure 2.

Referring to Fig. 6, the dispensing device of second embodiment is with the different of Fig. 3, interweaved (S810 and S812) by first interleaver 218 from the data of convolution coder 530 output, from the data of TURBO encoder 570 outputs that utilize TURBO sign indicating number or TURBO-TCM sign indicating number by second interleaver 580 interweave (S820 and S822).That is,, interweaved respectively by diverse ways from the data of convolution coder 530 outputs and the data of exporting from TURBO encoder 570 according to second embodiment.Other steps are identical with Fig. 3's.

As mentioned above, to data that send by the HP level and the different error correcting code of data allocations that sends by the LP level, and carry out different interweaving according to the dispensing device of digit broadcasting system of the present invention.Therefore, because differently coded data is with error correction according to sending level, the effective transmission that therefore is suitable for the communication environment of receiver is possible.

In addition, the above embodiments use the OFDM of DVB-T system to be used as modulator approach by example, but this should not be taken as qualification.The present invention can be applied to the traditional various dispensing devices of digital broadcasting and no matter employed modulator approach how.

As mentioned above, for by the data of HP level transmission and the data that send by the LP level, utilize different encoders and interleaver to carry out error correction coding.Therefore, it is possible sending according to the valid data of the digital broadcasting of the communication environment of receiver.

The above embodiments and advantage only are exemplary, can not be as limitation of the invention.This study course can easily be applied to the device of other types.Explanation of the present invention is illustrative, does not limit the scope of claim.Many to one skilled in the art replacement forms, improvement and variation are obvious.In claims, device adds the function clause and attempts to cover the structure that this is described as carrying out the function of enumerating, the not only coordinate of structure, and equal structure.

Claims

1. the dispensing device of a digit broadcasting system, the transmission stream that wherein will import are divided into first and transmit stream and second and transmit stream, and encode respectively and first and second transmit and flow with error correction, and described dispensing device comprises:

Reed-Solomon encoder is used for transmitting stream for first and carries out the Reed-Solomon coding;

Piece product code encoder is used for transmitting stream execution block product code coding for second;

First and second outer interleaver are used for interweaving respectively from the data of Reed-Solomon encoder output and the data of exporting from piece product code encoder;

Convolution coder is used for carrying out convolutional encoding for the data that interweaved by first outer interleaver;

The TURBO encoder is used for carrying out coding for the data that interweaved by second outer interleaver;

Inner interleaver is used to interweave by the convolution coder coded data with by the data of TURBO encoder encodes; And

Modulating unit is used for digital modulation by inner interleaver data that interweave and the data that send modulation.

2. according to the dispensing device of claim 1, wherein piece product code encoder comprises:

First encoder is used for coding and transmits stream with error correction;

Another interleaver, data by first encoder encodes are used to interweave; And

Second encoder, the data that interweaved by described another interleaver of being used to encode are with error correction.

3. according to the dispensing device of claim 1, wherein said TURBO encoder utilizes TURBO-TCM sign indicating number or TURBO sign indicating number to carry out error correction.

4. according to the dispensing device of claim 2, wherein first and second encoders are to use the Bose-Chaudhuri-Hocquenghem Code device of BCH code.

5. according to the dispensing device of claim 1, wherein modulating unit utilizes OFDM to modulate the combine digital modulation.

6. according to the dispensing device of claim 5, wherein modulating unit comprises:

Mapping/OFDM modulator block is used for shining upon the data that interweaved by inner interleaver and carrying out the OFDM modulation with a kind of mapping method;

Pilot tone/system information is inserted piece, is used to mapping/OFDM modulator block to be provided for the pilot signal of signal Synchronization and channel estimating and about the information of sending mode;

Protection is inserted piece at interval, is used for inserting a protection at interval to the signal from the output of mapping/OFDM modulator block;

The digital-to-analogue conversion piece is used for carrying out digital-to-analogue conversion to inserting protection signal at interval; And

Radio block is used for the conversion of signals of digital-to-analogue conversion is high-frequency signal and sends this signal.

7. according to the dispensing device of claim 1, also comprise: first and second scramblers are used for transmitting the stream randomization to provide first and second to transmit stream to Reed-Solomon encoder and piece product code encoder with first and second respectively.

8. the dispensing device of a digit broadcasting system, the transmission stream that wherein will import are divided into first and transmit stream and second and transmit stream, and encode respectively and first and second transmit and flow with error correction, and described dispensing device comprises:

First inner interleaver is used to interweave by the convolution coder coded data;

Second inner interleaver, data by the TURBO encoder encodes are used to interweave; With

Modulating unit is used for digital modulation by first and second inner interleaver data that interweave and the data that send modulation.

9. according to the dispensing device of claim 8, wherein piece product code encoder comprises:

First encoder is used for coding and transmits stream with error correction;

Another interleaver, data by first encoder encodes are used to interweave; And

10. according to the dispensing device of claim 8, wherein the TURBO encoder utilizes TURBO-TCM sign indicating number or TURBO sign indicating number to realize error correction.

11. according to the dispensing device of claim 9, wherein first and second encoders are to use the Bose-Chaudhuri-Hocquenghem Code device of BCH code.

12. according to the dispensing device of claim 8, wherein first and second inner interleaver are with identical method interleaving data.

13. according to the dispensing device of claim 8, wherein first and second inner interleaver are with the diverse ways interleaving data.

14. according to the dispensing device of claim 8, wherein modulating unit utilizes OFDM to modulate the combine digital modulation.

15. according to the dispensing device of claim 14, wherein modulating unit comprises:

16. the dispensing device according to claim 8 also comprises: first and second scramblers are used for transmitting the stream randomization to provide first and second to transmit stream to Reed-Solomon encoder and piece product code encoder with first and second respectively.

17. the sending method of a digit broadcasting system, this digit broadcasting system are divided into input transfer stream, and the first transmission stream and second transmits stream and first and second transmission of encoding are respectively flowed with error correction, described sending method comprises step:

(a) transmit stream for first and carry out the Reed-Solomon coding with error correction, and the output first coding data;

(b) transmit stream execution block product code coding with error correction for second, and export second coded data;

(c) interweave respectively first and second coded datas and output first and second data that interweave;

(d) carry out convolutional encoding for first data that interweave;

(e) carry out the TURBO coding for second data that interweave;

(f) interweave again by the convolution coder coded data with by the data of TURBO encoder encodes; And

(g) data that interweave again of digital modulation and send modulated data.

18. according to the sending method of claim 17, wherein step (b) comprises step:

Coding transmits stream with error correction for the first time;

The data of interweaving encoding; And

The code interleaving coded data is with error correction for the second time.

19. according to the sending method of claim 17, wherein TURBO coding step (e) utilizes TURBO-TCM sign indicating number or TURBO sign indicating number to realize error correction.

20. according to the sending method of claim 18, wherein first and second coding steps utilize the BCH code coded data.

21. according to the sending method of claim 17, wherein step (f) is with identical method interweave convolution encoded data and TURBO coded data.

22. according to the sending method of claim 17, wherein step (f) is with diverse ways interweave convolution encoded data and TURBO coded data.

23. according to the sending method of claim 17, wherein step (g) is utilized the modulation of OFDM modulation combine digital.

24. according to the sending method of claim 17, wherein step (g) comprising:

(g1) shine upon the data that interweave again and carry out the OFDM modulation with mapping method;

(g2) be provided for the pilot signal of signal Synchronization and channel estimating and about the information of sending mode to mapping/OFDM modulation step;

(g3) insert protection at interval to signal from step (g1) output;

(g4) carry out digital-to-analogue conversion for inserting protection signal at interval;

(g5) conversion of signals with digital-to-analogue conversion is high-frequency signal and sends this signal.

25. according to the sending method of claim 17, wherein also comprise step: randomization first and second transmits stream respectively, transmits stream so that first and second of step (a) to be provided.