CN101697532B - Diversity reception-based quick tracking adaptive time domain equalization method - Google Patents
Diversity reception-based quick tracking adaptive time domain equalization method Download PDFInfo
- Publication number
- CN101697532B CN101697532B CN200910075740A CN200910075740A CN101697532B CN 101697532 B CN101697532 B CN 101697532B CN 200910075740 A CN200910075740 A CN 200910075740A CN 200910075740 A CN200910075740 A CN 200910075740A CN 101697532 B CN101697532 B CN 101697532B
- Authority
- CN
- China
- Prior art keywords
- equalizer
- weight coefficient
- time domain
- diversity reception
- equalization method
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
The invention discloses a diversity reception-based quick tracking adaptive time domain equalization method, which solves the technical problem of the high complexity of the adaptive equalization method adopting a least squares criterion under the condition of diversity reception in the prior art. The invention adopts a technical scheme that: the method is implemented by means of a plurality of paths of feed-forward equalizers, one path of feedback equalizer and matched management software in a time domain equalizer; by means of the least squares criterion, the method comprises the following steps: according to the attenuation condition of a channel, firstly performing estimation on a signal waveform for reducing a weight coefficient range of the equalizer; secondly performing exact operation on a weight coefficient increment by means of the matched management software and a formula and obtaining a final value; and finally updating the weight coefficient of the equalizer so as to realize the adaptive change of the coefficient of the equalizer. The diversity reception-based quick tracking adaptive time domain equalization method has the advantages of remarkably speeding up convergence, being capable of achieving the optimal reception of a plurality of diversity channels, improving the stability of an algorithm, improving the stability of a digital value of the equalizer and greatly reducing the complexity.
Description
Technical field
The invention belongs to communication technique field, disclose a kind of quick tracking adaptive time domain equalization method based on diversity reception, it relates to the adaptive equalizer in the fractional spaced DFF simple in structure.This method is particularly suitable under the low signal-to-noise ratio condition of frequency selectivity fast fading channel, being used to realize the big capacity reliable communication based on diversity reception.
Background technology
Along with the raising of scientific and technological level, in communication field, communication apparatus is also had higher requirement.Adaptive time domain equalization based on fractional spaced DFF is simple in structure, real-time, insensitive to timing error, and the coefficient of equalizer is along with the decline adaptive change of channel.In the time-domain adaptive equalization methods; Mainly according to two kinds of criterions: minimum mean square error criterion (MMSE; Minimum Mean Square Error) and criterion of least squares (LS, Least Square), based on the adaptive equilibrium method of these two kinds of criterions its characteristics are arranged respectively.Adaptive equilibrium method complexity based on the MMSE minimum mean square error criterion is low, but convergence rate is slow, and follow-up control is poor, at channel fast under the condition of decline, and variation that can't the adaptive tracing channel.Adaptive equilibrium method fast convergence rate, follow-up control based on the LS criterion of least squares are strong, but the lifting on the performance is a cost with its complexity height, and especially in the communication system based on diversity reception, complexity more unprecedentedly promotes.Based on to above-mentioned consideration, if can two kinds of thoughts respectively be got its advantage, performance advantage separately; Realize both fast convergence rates, the complexity of calculating is low again, the simple fast quick decline property that realizes adaptive channel; Prior art can not realize, to those skilled in the art's profit of making troubles.
Summary of the invention
The objective of the invention is in order to solve adaptive equilibrium method high technical problem of complexity under the diversity reception condition that prior art adopts criterion of least squares; Designed a kind of quick tracking adaptive time domain equalization method based on diversity reception; Advantage by criterion of least squares is transformed equalizer, realizes channel adaptive equalization effect fast.
The present invention for realizing the technical scheme that goal of the invention adopts is; A kind of quick tracking adaptive time domain equalization method based on diversity reception; Above method is to realize that by the multichannel feed forward equalizer in the time-domain equalizer, No. one feedback equalizer and supporting management software above-mentioned method is by criterion of least squares, according to the decline situation of channel; Signal waveform is at first carried out the budget for the weight coefficient scope of dwindling equalizer; Relend and help supporting management software and formula that the weight coefficient increment is carried out definite computing and draws final value, the weight coefficient of final updating equalizer is realized the adaptive change of equalizer coefficients.
The present invention utilizes the advantage of the fast convergence rate of criterion of least squares, at first channel waveform is carried out budget, has dwindled the scope of best final value, in this scope, carries out the method computing of partial update again and draws final value again, finds out the equalizer weight coefficient.
The present invention compares with background technology, has following advantage:
1. the present invention divides the feed forward equalizer of collection passage and No. one feedback equalizer to do whole consideration multichannel, adopts the exponential weighting criterion of least squares, and convergence rate is obviously accelerated, and can reach multichannel and divide the optimum of collection passage to receive.Owing to adopted fractional spaced Structure of Decision-feedback Equalization, thus this fast uniform method superior performance not only, and kept fractional spaced DFF to the insensitive advantage of timing error.
2. the present invention does not directly obtain weight coefficient in weight coefficient upgrades, but adopts renewal of weight coefficient residual quantity and error accumulation to next weight coefficient method for updating, has therefore improved the robustness of algorithm.
3. the present invention adopts and selects the maximum pairing equalizer weight coefficient of component of accumulated error vector mould value to carry out the residual quantity updating value that method for updating obtains weight coefficient, and the complexity of equalizer reduces with respect to the equalizer of existing employing exponential weighting criterion of least squares based on diversity reception greatly; Because the present invention adopts partial update method iteration to obtain more new increment of weight coefficient, has avoided matrix inversion operation, the numerical stability degree of equalizer improves.Because performance of the present invention is sane, complexity reduces greatly, therefore realized the purpose of practical applications.
Below in conjunction with accompanying drawing the present invention is elaborated.
Description of drawings
Fig. 1 is the treatment step flow chart that utilizes the equalizer of the inventive method.
Embodiment
Referring to Fig. 1; A kind of quick tracking adaptive time domain equalization method based on diversity reception; Above method is to realize that by the multichannel feed forward equalizer in the time-domain equalizer, No. one feedback equalizer and supporting management software above-mentioned method is by criterion of least squares, according to the decline situation of channel; Signal waveform is at first carried out the budget for the weight coefficient scope of dwindling equalizer; Relend and help supporting management software and formula that the weight coefficient increment is carried out definite computing and draws final value, the weight coefficient of final updating equalizer is realized the adaptive change of equalizer coefficients.
The present invention utilizes the advantage of the fast convergence rate of criterion of least squares, at first channel waveform is carried out budget, has dwindled the scope of best final value, in this scope, carries out the method computing of partial update again and draws final value again, finds out the equalizer weight coefficient.
The concrete treatment step of above-mentioned equalizer is:
A, multichannel feed forward equalizer and No. one feedback equalizer is supporting is connected draw the output valve of equalization processor by supporting formula;
B, the output valve of above equalizer is adjudicated, and extract error according to decision value and output valve;
C, by criterion of least squares, draw the error vector of each segment information, and anded goes out the cumulative errors vector;
D, vectorial according to accumulated error selects the maximum pairing equalizer weight coefficient of component of accumulated error vector mould value to upgrade;
E, vectorial according to the above equalizer weight coefficient of accumulated error vector sum incremental computations residual error.
F, repeating step A-E accomplish the weight coefficient renewal process of all code elements.
Above-mentioned step C adopts the iterative recursive algorithm to sue for peace.
Above-mentioned time-domain equalizer comprises multichannel feed forward equalizer, No. one feedback equalizer and equalization processor.
In conjunction with accompanying drawing, enumerate most preferred embodiment, the concrete steps of quick tracking adaptive equalization methods are following:
1. the accumulated error vector calculation is following: according to residual error vector before, feed forward equalizer and No. one feedback equalizer and the error that multichannel is divided the collection passage, obtain the accumulated error vector.Computing formula does
β
o(n)＝λr(n-1)+e
*(n)x(n)
In the formula, λ representes forgetting factor, β
o(n) the accumulated error vector value of expression accumulated error vector calculation module output; The residual error vector value of r (n-1) expression residual error computing module output; The input signal of the feed-forward signal of x (n) expression multichannel feed forward equalizer and the feedback signal module of No. one feedback equalizer, the error of e (n) expression equalizer judgement and the output of error extracting module.
2. the equalizer weight coefficient calculates: according to accumulated error vector, the pairing equalizer weight coefficient of the element increment that calculating cumulative error vector mould value is maximum.Equalizer weight coefficient incremental computations expression formula is expressed as
Δw
p＝β
op(n)/R(n)
p，p
In the formula, R (n) is and the relevant amount of input signal x (n), can be expressed as
P representes the maximum element sequence number of mould value in the accumulated error vector, promptly
p＝arg?max(|β
o(n)|)
β
Op(n) the maximum element of mould value in the expression accumulated error vector, R (n)
P, pThe capable p column element of the p of representing matrix R (n), Δ w
pExpression equalizer weight coefficient increment.Therefore, the weight coefficient of equalizer can be expressed as
w
p(n)＝w
p(n-1)+Δw
p
3. residual error vector calculation: according to accumulated error vector sum equalizer weight coefficient incremental computations residual error vector.Residual error vector calculation expression formula does
r(n)＝β
o(n)-Δw
pR(n)
(p)
In the formula, the residual error vector value of r (n) expression residual error computing module output, β
o(n) the accumulated error vector value of expression accumulated error vector calculation module output, Δ w
pExpression equalizer weight coefficient increment, R (n)
(p)The p column vector of representing matrix R (n).
Claims (3)
1. quick tracking adaptive time domain equalization method based on diversity reception; Above method is to realize by the multichannel feed forward equalizer in the time-domain equalizer, No. one feedback equalizer and supporting management software; It is characterized in that: described method is by criterion of least squares; According to the decline situation of channel, channel waveform is at first carried out the budget for the weight coefficient scope of dwindling equalizer, relend and help supporting management software and formula that the weight coefficient increment is carried out definite computing and draws final value; The weight coefficient of final updating equalizer is realized the adaptive change of equalizer coefficients;
The concrete treatment step of described equalizer is:
A, multichannel feed forward equalizer and No. one feedback equalizer is supporting is connected draw the output valve of equalization processor by supporting formula;
B, the output valve of above equalizer is adjudicated, and extract error according to decision value and estimated value;
C, by criterion of least squares, draw the error vector of each code element, and anded goes out the cumulative errors vector;
D, vectorial according to accumulated error selects the maximum pairing equalizer weight coefficient of component of accumulated error vector mould value to upgrade;
E, vectorial according to the above equalizer weight coefficient of accumulated error vector sum increment estimation residual error;
F, repeating step A-E accomplish the weight coefficient renewal process of all code elements.
2. a kind of quick tracking adaptive time domain equalization method based on diversity reception according to claim 1 is characterized in that: described step C adopts the iterative recursive algorithm to sue for peace.
3. a kind of quick tracking adaptive time domain equalization method based on diversity reception according to claim 1, it is characterized in that: described time-domain equalizer comprises multichannel feed forward equalizer, No. one feedback equalizer and equalization processor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910075740A CN101697532B (en) | 2009-10-19 | 2009-10-19 | Diversity reception-based quick tracking adaptive time domain equalization method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910075740A CN101697532B (en) | 2009-10-19 | 2009-10-19 | Diversity reception-based quick tracking adaptive time domain equalization method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101697532A CN101697532A (en) | 2010-04-21 |
| CN101697532B true CN101697532B (en) | 2012-09-05 |
Family
ID=42142606
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200910075740A Active CN101697532B (en) | 2009-10-19 | 2009-10-19 | Diversity reception-based quick tracking adaptive time domain equalization method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101697532B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5263033A (en) * | 1990-06-22 | 1993-11-16 | At&T Bell Laboratories | Joint data and channel estimation using fast blind trellis search |
| CN1820424A (en) * | 2003-06-02 | 2006-08-16 | 高通股份有限公司 | Receiving apparatus with hybrid equalizer and rake receiver and corresponding method of receiving |
-
2009
- 2009-10-19 CN CN200910075740A patent/CN101697532B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5263033A (en) * | 1990-06-22 | 1993-11-16 | At&T Bell Laboratories | Joint data and channel estimation using fast blind trellis search |
| CN1820424A (en) * | 2003-06-02 | 2006-08-16 | 高通股份有限公司 | Receiving apparatus with hybrid equalizer and rake receiver and corresponding method of receiving |
Non-Patent Citations (2)
| Title |
|---|
| Minglu Jin.Partial updating RLS algorithm.《ICSP"04 Proceedings》.2004, * |
| 孟维晓 等.RLS算法智能天线空时联合均衡技术.《哈尔滨工业大学学报》.2005,第37卷(第6期), * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101697532A (en) | 2010-04-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103947106B (en) | It is a kind of to be used to make method, system and the equipment of nonlinear system element linearisation | |
| CN1689292B (en) | Communication receiver with virtual parallel equalizers | |
| CN104521176B (en) | The dynamic optimization of carrier auxiliary performance for communication system | |
| CN105072064B (en) | A kind of fractional spaced multi-mode blind equalization method based on DNA heredity bat methods | |
| US8295341B2 (en) | Cognitive radio device | |
| KR20110000668A (en) | Method and apparatus for adaptive channel estimation in a communication system | |
| CN1402924A (en) | Power efficient equalization | |
| US8885699B2 (en) | Compensation factor reduction in an unrolled decision feedback equalizer | |
| CN108881075B (en) | Channel estimation method based on robust adaptive filtering in impulsive noise environment | |
| CN112598106A (en) | Complex channel equalizer design method based on complex value forward neural network | |
| CN101697532B (en) | Diversity reception-based quick tracking adaptive time domain equalization method | |
| CN104410593A (en) | Decision feedback model-based digital symbol nonlinear error correction equalization method | |
| CN110855269A (en) | Adaptive filtering coefficient updating method | |
| CN101009671A (en) | Applicable equalizer and equalization method | |
| CN101179341B (en) | Channel identification system and electronic dispersion compensation system | |
| JP2004128833A (en) | Distortion compensator with multiple equalizer filter | |
| CN103905347A (en) | OFDM system fast-change channel estimation method based on double weighing | |
| CN111291511A (en) | Soft Kalman filtering iteration time-varying channel estimation method based on historical information | |
| CN106330792A (en) | In-band noise-filtering channel estimation algorithm and in-band noise-filtering channel estimation based on DTF transform domain | |
| CN101291308B (en) | Adaptive channel equalizer based on two-dimensional interpolation and method therefor | |
| CN114143152B (en) | Constant modulus blind equalization method based on fractional order correlation entropy and fractional order gradient | |
| CN106254286B (en) | The adaptive blind equalization method and device of high-speed parallel processing | |
| CN102299875B (en) | Wavelet multimode blind equalization method introducing immune-optimized SVM (Support Vector Machine) | |
| CN1818850A (en) | Method and device for execution multiplication or division operation in electronic circuit | |
| CN1239033C (en) | Discrete Fourier transform based space-time combined inspecting device and method for radio transmission |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |