CN1494287A - Channel equalizer of single carrier wave receiver and its equalizing method - Google Patents
Channel equalizer of single carrier wave receiver and its equalizing method Download PDFInfo
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- CN1494287A CN1494287A CNA031566553A CN03156655A CN1494287A CN 1494287 A CN1494287 A CN 1494287A CN A031566553 A CNA031566553 A CN A031566553A CN 03156655 A CN03156655 A CN 03156655A CN 1494287 A CN1494287 A CN 1494287A
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Abstract
A channel equalizer of a single carrier receiver of improved equalization efficiency includes a feed-forward filter that removes a pre-ghost from respective symbols of a broadcasting signal, a feedback filter that removes a post-ghost from the respective symbols of the broadcasting signal, an adder that adds the pre-ghost removed symbols with the post-ghost removed symbols, a level decision unit that determines a level of the symbols added at the adder with reference to predetermined level data and then feeds back the determined level to the feedback filter, a trellis decoder that performs trellis decoding with respect to the symbols added at the adder and has a whole decoding depth as N (N=natural number), and a whole length of a trace back delay as NxK (K=natural number), an error calculator that calculates an error value between the symbols added at the adder and the level determined at the level decision unit, and a trellis control unit that controls the trellis decoder so that a plurality of decoded symbols output from the trellis decoder can be input to the feedback filter in correspondence to the error obtained at the error calculator.
Description
Technical field
The present invention relates to the channel equalizer of single-carrier receiver, more particularly, relate to and utilize a plurality of decoding symbols that the trellis code decoder provides that channel circumstance is carried out the channel equalizer of the single-carrier receiver of received signal equilibrium, with and channel equalization method.
Background technology
About the transmission plan of digital broadcast signal, mainly contain residual sideband (VSB) modulation scheme and coded orthogonal frequency division multiplexing (COFDM) modulation scheme.The VSB modulation scheme is utilized the single carrier transmission broadcast singal.The COFDM modulation scheme is multiplexed and transmission broadcast singal by a plurality of transmission channels.The VSB modulation scheme is a kind of U.S. digital broadcast transmission scheme, comprised that many countries of the Korea S and the U.S. adopt, and the COFDM modulation scheme is a kind of European digital broadcast transmission scheme.
The current standard that the VSB modulation of U.S.'s land ripple (terrestrial wave) Digital Television is adopted is ATSC-8VSB, and it is converted to 8 grades with the broadcast singal of transmission.Simultaneously, vsb receiver receives the broadcast singal of having been modulated by the VSB modulation.Vsb receiver has been provided a channel equalizer, is used for the distortion that equilibrium appears at transmission channel.
Fig. 1 is illustrated in the schematic diagram of the channel equalizer that adopts in traditional single-carrier receiver by way of example.The channel equalizer of single-carrier receiver comprises feedforward filter 10, feedback filter 30, adder 40 and slicer 50.Channel equalizer with feedforward filter 10 and feedback filter 30 is called as decision zeedback equalizer (DFE).
The influence of ghost image before feedforward filter 10 is eliminated from each symbol of broadcast singal, feedback filter 30 is eliminated the influence of back ghost image from each symbol of broadcast singal.Adder is eliminated the back with preceding ghost image and is eliminated the residue addition that the back obtains from feedback filter 30 from the residue that feedforward filter 10 obtains with the back ghost image.
Utilize the channel equalizer of Fig. 1, determine other data of level as the input of feedback filter 30 by slicer 50 inputs.If when definite rank data, in slicer 50, error occurred,, and in adder 40, be added on the output valve of feedforward filter 10 just these error level data are passed through feedback filter 30 so.
Simultaneously, when determining the rank data according to the number of levels that is provided with for broadcast singal, slicer 50 has different performances usually.For example, for the same electrical value of broadcast singal, have 8 grades 8-VSB and be modulated at and have a gap between the signal rank, this gap is to have 4 grades half of 4-VSB modulation signal rank gap.Therefore, slicer may have the possibility that the rank data of error determine has increased.
Error propagation has taken place in the error increase along with slicer 50 in feedback filter 30.Further, according to the error of slicer 50, signal to noise ratio (snr) has reduced widely, therefore, has reduced the performance of channel equalizer, and has reduced the receptivity of single-carrier receiver on the whole.
For fear of the mis-behave of the channel equalizer that brings by slicer 50 definite error level data, can adopt trellis coded modulation (TCM) that the signal that is input to channel equalizer is carried out the trellis code coding.
Fig. 2 illustrates that to be suitable for being used in traditional single-carrier receiver be another kind of channel equalizer in traditional vsb receiver.As shown in Figure 2, channel equalizer comprises feedforward filter 10, feedback filter 30, adder 40, slicer 50, computing unit 60 and trellis coded modulation (TCM) unit 70.
Feedforward filter 10 is eliminated the preceding ghost image influence of each symbol of broadcast singal.Feedback filter 30 is eliminated the back ghost image of each symbol of broadcast singal.The residue that adder 40 obtains in feedforward filter 10 after preceding ghost image is eliminated is added on the residue that obtains in feedback filter 30 after the back ghost image is eliminated.Slicer 50 judges that other signal level of level is other recently in the intended level that adder 40 obtains.
The difference of computing unit 60 computation adder 40 and slicer 50 output valves.70 pairs of adder 40 output valves in TCM unit are carried out the trellis code decoding.TCM unit 70 feeds back to trellis code decoded results value in the feedback filter 30.Therefore, feedback filter 30 is eliminated the back ghost image according to the trellis code decoded data of 70 feedbacks from the TCM unit from each symbol of broadcast singal.
The caused feedback delay because trellis code is decoded is eliminated from each symbol in the predetermined amount of time of back ghost image according to the value of exporting from slicer 50 at feedback filter 30, and the trellis code decoded data is imported in the feedback filter 30.Therefore, feedback filter 30 must be eliminated the back ghost image according to determined rank data in slicer 50 from each symbol, imports from TCM up to the trellis code decoded data, and this can cause slicer 50 to determine these rank data mistakenly.
Further, the ghost image that therein broadcast singal is had an intractable (robust) is under the channel circumstance that just exists before the output delay of TCM unit 70, even can not guarantee higher equalization performance in the channel equalizer that uses TCM unit 70.
Summary of the invention
Therefore, one aspect of the present invention provides a kind of channel equalizer that uses the trellis code decoding to eliminate residual sideband (VSB) equalizer of ghost image, even broadcast singal being had obstinate ghost image is also can improve equalization performance under the channel circumstance that exists before the output delay that trellis code decoding causes, with and channel equalization method.
Another aspect of the present invention and advantage will partly propose in the following description, partly be conspicuous from specification, or can be known by practice of the present invention.
In order to realize above-mentioned and/or others of the present invention, the channel equalizer that has improved the single-carrier receiver of balanced efficient comprises the feedforward filter of eliminating preceding ghost image from each symbol of broadcast singal; From each symbol of broadcast singal, eliminate the feedback filter of back ghost image; The symbol of having eliminated preceding ghost image is added to the adder on the symbol of having eliminated back ghost image; Determine the symbol rank of addition on adder with reference to the data of intended level, then with determined level feedback to feedback filter; The symbol of addition on adder is carried out the trellis code decoding, and the total length that has total depth of decode N (N=natural number) and review delay is the trellis code decoder of N * K (K=natural number); The Error Calculator of error amount between the rank that the symbol of calculating addition in adder and rank identifying unit are determined; And control trellis code decoder is so that can be imported into the trellis code control unit of feedback filter from a plurality of decoding symbols of trellis code decoder output according to the error that obtains in Error Calculator.
When trellis code control unit control trellis code decoder was equal to or greater than predetermined threshold value with the box lunch signal to noise ratio (snr) corresponding with error amount, decoding symbols was imported in the feedback filter.
Be imported into the 1+ of feedback filter (in the individual filter tap of n * K) from the decoding symbols of depth of decode state n (n≤N, N=natural number) output.Therefore, the decoding symbols from the output of depth of decode state is input to respectively the respective filter tap of feedback filter.
Be used to from other input of the determined level of rank identifying unit, feedback filter is eliminated the back ghost image of each symbol according to determined rank, and, being used to another input from the decoding symbols of trellis code decoder, feedback filter is eliminated the back ghost image according to the symbol of decoding.
Simultaneously, in order to realize above-mentioned and/or others of the present invention, the channel equalization method of single-carrier receiver comprises, utilizes feedforward filter to eliminate the preceding ghost image of each symbol of input signal; Utilize feedback filter to eliminate the back ghost image of each symbol of input signal; In conjunction with the symbol of having eliminated preceding ghost image and the symbol of having eliminated back ghost image; Carry out feedback operation, this feedback operation judges that with reference to the data of intended level summation as the symbol of corresponding level is to import determined rank to feedback filter; According to predetermined error update algorithm, calculate these symbol summations and the error between definite rank; Carry out the trellis code decode operation, utilize the trellis code decoder to carry out the trellis code decoding; And executive control operation, whether this control operation is imported from a plurality of decoding symbols of trellis code decoder output to feedback filter according to the ERROR CONTROL of calculating.
When the signal to noise ratio corresponding to error amount was equal to or greater than predetermined threshold value, control operation will be input in the feedback filter from the decoding symbols of trellis code decoder.
Be imported into the 1+ of feedback filter (in the individual filter tap of n * K) from the decoding symbols of depth of decode state n (n≤N, N=natural number) output.Therefore, the decoding symbols from the output of depth of decode state is input to respectively the respective filter tap of feedback filter.
Feedback filter is eliminated the back ghost image according to determined rank from each symbol, and, be used to input from the decoding symbols of trellis code decoder, from each symbol, eliminate the back ghost image according to decoding symbols.
The result, even when the SNR of the error amount correspondence that obtains on Error Calculator is equal to or greater than predetermined threshold value, still avoided because the error level of rank identifying unit is judged the balanced efficient reduction that causes according to the feedback filter of carrying out filtering from the decoded data of trellis code decoder input.
Description of drawings
Consider in conjunction with following accompanying drawing, from following description of a preferred embodiment, these and/or others of the present invention and advantage will become very clear and easy to understand.
Fig. 1 illustrates the schematic diagram that is suitable for use in the channel equalizer in traditional single-carrier receiver;
Fig. 2 illustrates the schematic diagram that is suitable for use in the another kind of channel equalizer in traditional single-carrier receiver;
Fig. 3 is the schematic block diagram according to the single-carrier receiver of the embodiment of the invention;
Fig. 4 is the block diagram that is suitable for making in the single-carrier receiver shown in Figure 3 the channel equalizer that equalizer performance improves;
Fig. 5 is the schematic diagram of the trellis code decoded data output of key diagram 4 trellis code decoders;
Fig. 6 is the signal to noise ratio tabulation of listing according to the trellis code decoding output delay of Fig. 4 trellis code decoder;
Fig. 7 is the flow chart of the channel equalization method of single-carrier receiver shown in key diagram 3 and 4.
Embodiment
Below will be in detail with reference to the preferred embodiments of the present invention, these example shown are in the accompanying drawing, and wherein identical reference number all refers to identical parts in each place.Below embodiment will be described, so that the present invention is described with reference to the accompanying drawings.
Explain the present invention below with reference to the accompanying drawings.
Reference illustrates the Fig. 3 according to the block diagram of the vsb receiver of embodiments of the invention, vsb receiver is described, a kind of structure of single-carrier receiver.Below the example of vsb receiver as single-carrier receiver described.But the present invention is not limited to this.
As shown in Figure 3, vsb receiver comprises demodulator 81, distortion compensator 82, comb filter 83, channel equalizer 84, phase place recovery unit 85, trellis code decoder 87, deinterleaver 88 and Read-Solomon demodulator 89.
Demodulator 81 is converted to baseband bandwidth with the RF bandwidth broadcast singal that receives.82 pairs of broadcast singals from demodulator 81 outputs of distortion compensator, recovery segment sync signal, field synchronization are signal and symbol sequential signal.Comb filter 83 is eliminated NTSC (national television system committee) interference signal from the broadcast singal by demodulator 81 outputs.
The channel distortion that channel equalizer 84 compensation take place during the broadcast singal transmission is by transmission channel.Phase place recovery unit 85 recovers the phase place of the broadcast singal after the channel distortion compensation.87 pairs of trellis code decoders have the broadcast singal of phase distortion and carry out the trellis code decoding, and these distortions have been resumed in phase place recovery unit 85.Deinterleaver 88 is corresponding to interweaving of carrying out in transmitter, and execution deinterleaves to trellis code decoding broadcast singal.Read-Solomon demodulator 89 is carried out decoding corresponding to the Reed Solomon Coding of carrying out to the broadcast singal that deinterleaves in transmitter.
Fig. 5 illustrates an example of trellis code decoder 87 shown in Figure 3.Total depth of decode of trellis code decoder 87 has state 0,1,2 ..., N, and, be that unit carries out under the situation about deinterleaving with the individual symbol of K (K=natural number), total reviewing postpones to have symbol lengths K * N.In other words, when total depth of decode of trellis code decoder 87 is at state 0,1,2 ..., during N, from whole decoded data d
0, d
1..., d
NIn a plurality of specific decoded data d that selects at random
0, d
1..., d
n(n≤natural number) is fed back in the channel equalizer 84.Therefore, according to the specific decoded data from trellis code decoder 87 feedbacks, each symbol of 84 pairs of broadcast singals of channel equalizer is carried out channel equalization.
Fig. 4 is the block diagram that is suitable for use in the single-carrier receiver vsb receiver for example shown in Figure 3 with the channel equalizer that improves equalization performance.The channel equalizer of Fig. 4 is as channel equalizer 84 shown in Figure 3, phase place recovery unit 85 and trellis code decoder 87.
As shown in Figure 4, channel equalizer comprises feedforward filter 110, feedback filter 120 and adder 130, trellis code decoder 140 (the trellis code decoder 87 among Fig. 3), rank identifying unit 150, error calculation unit 160, and trellis code controller 170.
Preceding ghost image elimination value M that adder 130 will be exported from feedforward filter 110 and the back ghost image elimination value L addition of exporting from feedback filter 120.Trellis code decoder 140 utilizes the end value Y that obtains in adder 130 to carry out the trellis code decoding.
According to the error value E that provides by Error Calculator 160, the operation of trellis code control unit 170 control trellis code decoders 140.More particularly, when with Error Calculator 160 in the corresponding signal to noise ratio (snr) of error value E that obtains when being equal to or greater than predetermined threshold value, trellis code control unit 170 control trellis code decoders 140, so that with specific depth of decode state promptly from total depth of decode state 0,1,2 ..., the corresponding specific decoded data d of depth of decode state that selects at random among the N
0, d
1..., d
nBe imported in a plurality of respective filter taps of feedback filter 120.
Fig. 5 has represented decoded data d
0, d
1..., d
nFrom total depth of decode state 1,2 ..., the situation of n (n≤N, natural number) output.Corresponding to reviewing delay length, decoded data d
0, d
1..., d
nBe imported into respectively in the respective filter tap of feedback filter 120.Therefore, from the data d of the decoding of depth of decode state ' 0 ' output
0Be imported on first filter tap of feedback filter 120, and from the decoded data d of depth of decode state ' 1 ' output
1With K symbol is unit output, outputs on (1+K) individual filter tap like this.Decoded data d from depth of decode state ' n ' output
nThe 1+ that is imported into filter 120 is (on the individual filter tap of n * K).
When end value Y was carried out the trellis code decoding, under the control of trellis code control unit 170, trellis code decoder 140 will be from the decoded data d of specific depth of decode state output
0, d
1..., d
nBe input to respectively in the respective filter tap.Therefore, feedback filter 120 is according to the decoded data d from 140 inputs of trellis code decoder
0, d
1..., d
n, eliminate the back ghost image of each symbol.
Therefore, feedback filter 120 is carried out the back ghost image and is eliminated filtering according to the definite rank data from rank identifying unit 150 feedbacks, and, as decoded data d
0, d
1..., d
nBy from trellis code decoder 140 input the time, according to decoded data d
0, d
1..., d
nCarrying out the back ghost image of each symbol eliminates.
As a result, just can avoid determining the error propagation of the feedback filter 120 that brings owing to the rank data of rank identifying unit 150 mistakes.
Fig. 6 is the output delay according to the trellis code decoding, the signal to noise ratio tabulation of trellis code decoder 140 output signals.The broadcast singal that uses in this experiment is Brazilian D channel.
As shown in Figure 6, when the depth of decode of trellis code decoder 140 was ' 0 ', Brazilian D channel had maximum SNR.Therefore, just may be trellis code decoded data d
0Be input to the feedback filter 120 from trellis code decoder 140.Therefore, because trellis code decoded data d
0Be imported into from trellis code decoder 140 in the feedback filter 120, balanced efficient has improved widely, even the front portion of broadcast singal has comprised and has obstinate ghost image in the Brazilian D channel.
The flowcharting of Fig. 7 uses channel equalizer shown in Figure 4 to improve the channel equalization method of channel equalization efficient.The some parts that to ignore the Fig. 7 that illustrated with reference to figure 4 and Fig. 5 below.
At first, in operation S110, feedforward filter 110 is eliminated preceding ghost image from each symbol of broadcast singal, thereby output signal M.In operation S120, feedback filter 120 is eliminated the back ghost image from each symbol of broadcast singal, thereby output signal L.
In operation S130, the signal M that adder 130 will be eliminated preceding ghost image and export from feedforward filter 110, and the signal L addition of having eliminated back ghost image and having exported, thereby output summation signals (end value) Y from feedback filter 120.In operation 140, the summation signals Y of 140 pairs of adders 130 of trellis code decoder carries out the trellis code decoding.
In operation S150, rank identifying unit 150 is determined summation signals Y nearest other rank of level in the middle of intended level of adder 130.Therefore, rank identifying unit 150 to feedback filter 120 and Error Calculator 160 provide determine other signal of level D.In operation S160, according to predetermined error update algorithm, Error Calculator 160 error of calculation value E, i.e. poor between the determined rank data D of the summation signals Y of adder 130 and rank identifying unit 150.Error Calculator 160 provides the error value E that calculates to feedforward filter 110, feedback filter 120 and trellis code control unit 170.Feedforward filter 110 and feedback filter 120 come update coefficients according to the error value E that is provided by Error Calculator 160.
Simultaneously, in operation S170, according to the error value E that is provided by Error Calculator 160, trellis code control unit 170 is controlled the time point that the trellis code decoded data of trellis code decoder 140 when is imported into feedback filter 120.When being equal to or greater than predetermined threshold value with the corresponding SNR of error value E that is obtained by Error Calculator 160, trellis code control unit 170 control trellis code decoders 140 are to the data of feedback filter 120 input decodings in operation S170.
Therefore, carry out the feedback filter 120 that the back ghost image is eliminated filtering, carry out the back ghost image of each symbol according to the decoded data that receives from trellis code decoder 140 and eliminate according to the other data of defining the level really from rank identifying unit 150 feedbacks.
Therefore, by the error propagation of avoiding occurring in feedback filter owing to the error of rank identifying unit, the equalization performance of channel equalizer just has been reinforced.
According to the present invention, even when being equal to or greater than predetermined threshold value with the corresponding SNR of the error amount that in Error Calculator, obtains, determine the decline of the balanced efficient that produces owing to the error level of rank identifying unit, carry out filtering by feedback filter according to the decoded data of importing from the trellis code decoder and avoided.
Though embodiments of the invention have been described above, but this professional those of ordinary skill will be appreciated that, the present invention should not be confined to illustrated preferred embodiment, and at the accessory claim book and be equal in the defined spirit and scope and can make various variations and modification.
The application requires the interests of on September 19th, 2002 in the patent application of the Korean Patent Application No. 2002-57399 that Korea S Department of Intellectual Property submits to, and the explanation of this patent application is contained in this with for referencial use.
Claims (37)
1. the channel equalizer of the single-carrier receiver of a receiving inputted signal comprises:
Feedforward filter, the preceding ghost image of each symbol of elimination input signal;
Feedback filter, the back ghost image of each symbol of elimination input signal;
Adder is in conjunction with the symbol of having eliminated preceding ghost image and the symbol of having eliminated back ghost image;
The rank identifying unit with reference to the data of intended level, is determined the symbol rank of addition in adder, and with determined level feedback in feedback filter;
The trellis code decoder is carried out the trellis code decoding to the symbol summation that obtains in the adder;
Error Calculator, calculate the symbol in adder, obtain and in the rank identifying unit the error amount between definite rank;
The trellis code control unit, control trellis code decoder so that according to the error amount that obtains in Error Calculator, is input to a plurality of decoding symbols of exporting in the trellis code decoder in the feedback filter.
2. channel equalizer as claimed in claim 1, wherein, trellis code control unit control trellis code decoder, when being equal to or greater than predetermined threshold value with box lunch corresponding to the signal to noise ratio (snr) of described error amount, decoding symbols is imported in the feedback filter.
3. channel equalizer as claimed in claim 1, wherein, the trellis code decoder comprises:
Total depth of decode is N (a N=natural number);
The total length of reviewing delay is N * K (a K=natural number).
4. channel equalizer as claimed in claim 3, wherein, the trellis code decoder is input to decoding symbols in the feedback filter, and these decoding symbols are to export from a plurality of depth of decode states of total depth of decode.
5. channel equalizer as claimed in claim 4, wherein, from depth of decode state n (n≤N, the N=natural number) Shu Chu decoding symbols is imported into the 1+ of feedback filter (in the individual filter tap of n * K), and, be input to respectively the respective filter tap of feedback filter from the decoding symbols of depth of decode state output.
6. channel equalizer as claimed in claim 1, wherein, utilization is determined rank input in the rank identifying unit, feedback filter is eliminated the back ghost image according to the rank of being judged from each symbol, and be used to another input from the decoding symbols of trellis code decoder, feedback filter is eliminated the back ghost image according to decoding symbols from each symbol.
7. the channel equalization method of the single-carrier receiver of receiving inputted signal comprises:
Ghost image before using feedforward filter from each symbol of input signal, to eliminate;
Use feedback filter from each symbol of input signal, to eliminate the back ghost image;
In conjunction with the symbol of having eliminated preceding ghost image and the symbol of having eliminated back ghost image;
Carry out feedback operation, this feedback operation is determined symbol summation as appropriate level with reference to the data of intended level, and imports determined rank to feedback filter;
According to predetermined error update algorithm, the error between compute sign summation and the determined appropriate level;
Carry out the trellis code decode operation, this trellis code decode operation utilizes the trellis code decoder that these symbols are carried out the trellis code decoding;
Control trellis code decoder is so that determine whether be input to the feedback filter from the decoding symbols of trellis code decoder output according to the error that calculates.
8. channel equalization method as claimed in claim 7, wherein the control of trellis code decoder comprises:
When the signal to noise ratio corresponding to error amount is equal to or greater than predetermined threshold value, decoding symbols is input to the feedback filter from the trellis code decoder.
9. channel equalization method as claimed in claim 7, wherein, the trellis code decoder in the trellis code decode operation comprises:
Total depth of decode is N (a N=natural number);
The total length of reviewing delay is N * K (a K=natural number).
10. channel equalization method as claimed in claim 9, wherein the trellis code decoder is input to decoding symbols in the feedback filter, and these decoding symbols are to export from a plurality of depth of decode states of total depth of decode.
11. channel equalizer as claim 10, wherein from depth of decode state n, n is equal to or less than N, the 1+ that the decoding symbols of output is imported into feedback filter (in the individual filter tap of n * K), and is input to respectively the respective filter tap of feedback filter from the decoding symbols of depth of decode state output.
12. channel equalization method as claim 10, wherein, feedback filter is eliminated the back ghost image according to the rank of being judged from each symbol, and, according to input, from each symbol, eliminate the back ghost image according to decoding symbols from the decoding symbols of trellis code decoder.
13. the single-carrier receiver of receiving inputted signal comprises:
Recovery unit is used for recovering primary signal from input signal;
The phase place recovery unit is used to recover the phase of input signals distortion;
Channel equalizer, being used for the trellis code depth of decode is unit, utilizes decoding symbols that the input signal that has recovered phase distortion is carried out channel equalization;
Deinterleaver is used for deinterleaving to carrying out from the input signal after the channel equalization of channel equalizer;
The Read-Solomon demodulator is used for the input signal after deinterleaving is carried out the Read-Solomon decoding.
14. as the single-carrier receiver of claim 13, wherein recovery unit comprises:
Demodulator is used for input signal is converted to baseband bandwidth;
The distortion compensation unit is used for recovering segment sync signal, field sync signal and the distortion of one of them at least of baseband bandwidth input signal symbol sequential;
Comb filter is eliminated NTSC (national television system committee) interference signal from the input signal that has recovered distortion.
15. as the single-carrier receiver of claim 13, wherein channel equalizer comprises:
Feedforward filter, the preceding ghost image of each symbol of elimination input signal;
Feedback filter, the back ghost image of each symbol of elimination input signal;
Adder is in conjunction with the symbol of having eliminated preceding ghost image and the symbol of having eliminated back ghost image;
The rank identifying unit with reference to the data of intended level, is determined the symbol rank of addition in adder, and with determined level feedback in feedback filter;
The trellis code decoder is carried out the trellis code decoding to the symbol summation that obtains in the adder;
Error Calculator, calculate the symbol in adder, obtain and in the rank identifying unit the error amount between definite rank;
The trellis code control unit, control trellis code decoder so that according to the error amount that obtains in Error Calculator, is input to a plurality of decoding symbols of exporting in the trellis code decoder in the feedback filter.
16. as the single-carrier receiver of claim 15, wherein the trellis code decoder comprises:
Total depth of decode is N (a N=natural number);
The total length of reviewing delay is N * K (a K=natural number).
17. as the single-carrier receiver of claim 16, wherein, the trellis code decoder is input to decoding symbols in the feedback filter, these decoding symbols are to export from a plurality of depth of decode states of total depth of decode.
18. as the single-carrier receiver of claim 15, wherein, when the signal to noise ratio corresponding to described error was equal to or greater than predetermined threshold value, trellis code control unit control trellis code decoder will be input to the feedback filter from the decoding symbols of trellis code decoder output.
19. single-carrier receiver as claim 18, wherein from depth of decode state n, (n≤N, the N=natural number) Shu Chu the decoding symbols 1+ that is imported into feedback filter (in the individual filter tap of n * K), and is input to respectively the respective filter tap of feedback filter from the decoding symbols of depth of decode state output.
20. single-carrier receiver as claim 15, wherein, according to other input of determined definite level in the rank identifying unit, feedback filter is eliminated the back ghost image according to definite rank from each symbol, and according to another input from the decoding symbols of trellis code decoder, feedback filter is eliminated the back ghost image according to decoding symbols from each symbol.
21. the single-carrier receiver of receiving inputted signal comprises:
Channel equalizer, eliminate the preceding ghost image and the back ghost image of each symbol of input signal, and eliminated the summation of the symbol of preceding ghost image and back ghost image according to predetermined rank data and input signal, input signal has been eliminated the summation of the symbol of preceding ghost image and back ghost image and carried out the trellis code decoding.
22. as the single-carrier receiver of claim 21, wherein channel equalizer comprises:
Feedback filter is used for eliminating the back ghost image from each symbol of input signal;
Feedforward filter is used for eliminating preceding ghost image from each symbol of input signal.
23. as the single-carrier receiver of claim 21, wherein channel equalizer comprises:
The rank identifying unit is determined the rank of symbol according to the data of intended level, and with determined level feedback in feedback filter.
24. as the single-carrier receiver of claim 23, wherein the rank identifying unit has determined to eliminate the rank of the symbol of preceding ghost image and back ghost image according to the data of intended level.
25. as the single-carrier receiver of claim 23, wherein feedback filter has been eliminated the symbol of preceding ghost image according to determined rank output.
26. as the single-carrier receiver of claim 23, wherein channel equalizer comprises:
Error Calculator, be used to calculate definite rank and input signal elimination the error amount between the summation of symbol of preceding ghost image and back ghost image.
27. as the single-carrier receiver of claim 26, wherein channel equalizer comprises:
The trellis code decoder is used for the error amount according to Error Calculator, to the elimination of input signal the summation of symbol of preceding ghost image and back ghost image carry out the trellis code decoding.
28. as the single-carrier receiver of claim 27, wherein channel equalizer comprises:
Controller, be used for controlling the trellis code decoder with to the elimination of feedback filter transferring input signal the decoding summation of symbol of preceding ghost image and back ghost image.
29. as the single-carrier receiver of claim 28, wherein feedback filter is eliminated the back ghost image symbol of input signal according to the decoding summation.
30. as the single-carrier receiver of claim 21, wherein channel equalizer transferring input signal in feedback filter has been eliminated the decoding summation of the symbol of preceding ghost image and back ghost image.
31. as the single-carrier receiver of claim 30, wherein channel equalizer produce according to error amount input signal elimination the symbol of back ghost image.
32. as the single-carrier receiver of claim 30, wherein channel equalizer according to the elimination of input signal the decoding summation of symbol of preceding ghost image and back ghost image, the elimination of generation input signal the symbol of back ghost image.
33. as the single-carrier receiver of claim 21, wherein channel equalizer is to the decoding symbols of feedback filter transferring input signal, so that feedback filter is eliminated ghost image behind the symbol of input signal according to the summation of decoding.
34. the method to the symbol execution channel equalization of input signal in the single-carrier receiver, this method comprises:
Eliminate the preceding ghost image and the back ghost image of each symbol of input signal;
According to the elimination of the data of intended level and input signal the summation of symbol of preceding ghost image and back ghost image to the elimination of input signal the summation of symbol of preceding ghost image and back ghost image carry out the trellis code decoding.
35. as the method for claim 34, wherein to the elimination of input signal the summation of symbol of preceding ghost image and back ghost image carry out the trellis code decoding and comprise:
Determine the rank of described summation according to the data of intended level;
With determined level feedback in feedback filter.
36. as the method for claim 35, the back ghost image of wherein eliminating each symbol of input signal comprises:
According to the output of definite rank eliminated the symbol of back ghost image.
37. as the method for claim 35, wherein to the elimination of input signal the summation of symbol of preceding ghost image and back ghost image carry out the trellis code decoding and comprise:
According to the elimination of described determined value and input signal the error amount between the summation of symbol of preceding ghost image and back ghost image, to the elimination of feedback filter transferring input signal the decoding summation of symbol of preceding ghost image and back ghost image.
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR20020057399 | 2002-09-19 | ||
| KR57399/2002 | 2002-09-19 | ||
| KR57399/02 | 2002-09-19 | ||
| KR443/03 | 2003-01-04 | ||
| KR443/2003 | 2003-01-04 | ||
| KR1020030000443A KR20040025516A (en) | 2002-09-19 | 2003-01-04 | Channel Equalizer of Single carrier Receiver and a method equalizing thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1494287A true CN1494287A (en) | 2004-05-05 |
| CN1258276C CN1258276C (en) | 2006-05-31 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 03156655 Expired - Fee Related CN1258276C (en) | 2002-09-19 | 2003-09-08 | Channel equalizer of single carrier wave receiver and its equalizing method |
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| Country | Link |
|---|---|
| JP (1) | JP2004112792A (en) |
| CN (1) | CN1258276C (en) |
| CA (1) | CA2440064C (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100364257C (en) * | 2005-05-26 | 2008-01-23 | 上海奇普科技有限公司 | Time-domain adaptive aqualizer combined with NR code |
| CN101106386B (en) * | 2006-07-14 | 2012-01-04 | 上海高清数字科技产业有限公司 | Time domain self-adapted balancer |
| WO2015135508A1 (en) * | 2014-03-13 | 2015-09-17 | Mediatek Inc. | Feedforward filter using translational filter |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100594275B1 (en) * | 2004-05-14 | 2006-06-30 | 삼성전자주식회사 | Digital television receiver having a channel state generation circuit for NTSC co-channel interference rejection and broadcasting signal processing method of the same |
| EP2068456A1 (en) * | 2006-09-28 | 2009-06-10 | Panasonic Corporation | Waveform equalizing device |
-
2003
- 2003-09-08 CN CN 03156655 patent/CN1258276C/en not_active Expired - Fee Related
- 2003-09-09 CA CA002440064A patent/CA2440064C/en not_active Expired - Fee Related
- 2003-09-10 JP JP2003318968A patent/JP2004112792A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100364257C (en) * | 2005-05-26 | 2008-01-23 | 上海奇普科技有限公司 | Time-domain adaptive aqualizer combined with NR code |
| CN101106386B (en) * | 2006-07-14 | 2012-01-04 | 上海高清数字科技产业有限公司 | Time domain self-adapted balancer |
| WO2015135508A1 (en) * | 2014-03-13 | 2015-09-17 | Mediatek Inc. | Feedforward filter using translational filter |
| US10084433B2 (en) | 2014-03-13 | 2018-09-25 | Mediatek Inc. | Feedforward filter using translational filter |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1258276C (en) | 2006-05-31 |
| CA2440064A1 (en) | 2004-03-19 |
| CA2440064C (en) | 2008-05-06 |
| JP2004112792A (en) | 2004-04-08 |
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