CN102006258A - Method and system for correcting frequency deviation - Google Patents
Method and system for correcting frequency deviation Download PDFInfo
- Publication number
- CN102006258A CN102006258A CN2009101949840A CN200910194984A CN102006258A CN 102006258 A CN102006258 A CN 102006258A CN 2009101949840 A CN2009101949840 A CN 2009101949840A CN 200910194984 A CN200910194984 A CN 200910194984A CN 102006258 A CN102006258 A CN 102006258A
- Authority
- CN
- China
- Prior art keywords
- signal
- domain filtering
- output
- frequency
- channel estimating
- 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.)
- Pending
Links
Images
Landscapes
- Radio Transmission System (AREA)
Abstract
The invention provides a method for correcting frequency deviation, comprising the following steps of: receiving an initial signal; sequentially carrying out initial channel estimation, channel estimation frequency-domain filtration and channel estimation time-domain filtration to the initial signal, wherein frequency deviation estimation is carried out to a signal which is subjected to the channel estimation frequency-domain filtration before the channel estimation time-domain filtration; carrying out frequency deviation elimination to the signal subjected to the channel estimation frequency-domain filtration. Correspondingly, the invention also provides a system for correcting frequency deviation. The invention can radically eliminate adverse effect caused by the frequency deviation in an LTE (Long Term Evolution) system.
Description
Technical field
The present invention relates to the frequency offset correction technology in Long Term Evolution (LTE) system, relate in particular to a kind of method and apparatus that is used for frequency offset correction of novelty.
Background technology
OFDM (OFDM) is a kind of multi-carrier modulation technology, has good anti-frequency selectivity and band efficiency.Ofdm system combines with multiaerial system and can all increase significantly aspect systematic function, is regarded as the key technology of next generation mobile communication.
Usually, in ofdm system, frequency deviation causes received signal that phase deviation takes place in frequency domain, introduce to disturb between subcarrier, makes the mis-behave of system.Though when frequency deviation hour, the influence of inter-carrier interference (ICI) is less, can be approximated to be noise, the influence of the phase deviation that causes owing to frequency deviation remains and can not ignore.Specifically, phase deviation brings the influence of two aspects: the deterioration of channel estimating time-domain filtering performance and the deterioration of demodulation performance.
Fig. 1 schematically shows prior art.As shown in Figure 1, in frame 101, at first reference signal (RS) is done channel estimating, obtain the channel estimation value at RS place.In frame 102, RS place channel estimation value is carried out frequency domain filtering, obtain containing the channel estimation value at each subcarrier place of RS symbol.In frame 103, the channel estimating behind the frequency domain filtering is done time-domain filtering, obtain the channel estimation value at all subcarrier places of all symbols.In frame 104, utilize the channel estimating information butt joint to receive data and do multiple-input and multiple-output (MIMO) detection, obtain the transmission sign estimation at each subcarrier place.
For above-mentioned frame 101, traditional ofdm system adopts the discrete RS that inserts of time-frequency domain to carry out channel estimating usually, relatively be typically least mean-square error (MMSE) channel estimating that adopts two dimension, promptly, carry out MMSE filtering in frequency domain, time domain respectively after the RS place initial channel estimation.With the LTE system is example, reference signal in the distribution of time-frequency domain as shown in Figure 2, the square of blue background is corresponding RS signal.Because the influence of frequency deviation, the signal of k subcarrier place of the 1st the OFDM symbol correspondence of reception is
r
K, lReceived signal when expression does not have frequency deviation, f
oThe expression frequency deviation, T
sExpression OFDM symbol period length, the channel response of establishing RS place, this position is h
K, l, r is then arranged
K, l=h
K, lx
K, l+ n
K, l, x wherein
K, lBe the RS signal that sends, n
K, lBe noise component(s).RS place initial channel estimation is
As seen, all comprised phase deviation in the channel estimating at each RS place, and phase deviation is only relevant with the time Domain Index 1 of OFDM symbol.
As shown in Figure 1, each subcarrier to each OFDM symbol after initial channel estimation carries out frequency domain filtering (frame 102), and filtering can be expressed as
Wherein,
The initial channel estimation result who represents RS place in the 1st the OFDM symbol, P is the frequency domain RS number of participation filtering,
Represent k the employed filter factor of subcarrier,
Only relevant with frequency domain correlation.As seen behind the frequency domain filtering, the phase difference that the channel response of each subcarrier correspondence of same OFDM symbol is introduced still remains unchanged, and does not consider the influence of noise item,
When not having frequency deviation
The pass is
For example, Fig. 3 shows the result of channel estimating behind the frequency domain filtering.
Subsequently, when time-domain filtering (frame 103), each OFDM symbol place channel estimating of same subcarrier is handled, filtering can be expressed as
Wherein,
The channel response at k each OFDM symbol place of subcarrier behind the expression frequency domain filtering,
Represent the 1st the employed filter factor of OFDM symbol,
Only relevant with the relativity of time domain that is caused by parameters such as Doppler's expansions, Q is for participating in the time domain symbolic number of filtering.This moment because
Each element between introduced different phase differences respectively, so channel estimating behind the time-domain filtering
Channel estimating when not having frequency deviation
Very big deviation is arranged, and this deviation not simple phase difference, very difficult foundation direct relation between the two.
As seen, above-mentioned channel estimation results is used for MIMO detects the severe exacerbation that can cause demodulation performance undoubtedly, deterioration reason is from two aspects, promptly introduced phase deviation in the received signal on the one hand, there are very big deviation in channel estimating and actual value on the other hand, and this deviation is not simple phase difference.This mis-behave is especially big to the influence of high-order modulating, is easy to cause the demodulation erroneous judgement.
But, disclosing as Fig. 1, prior art only is used as the influence of frequency deviation noise and is not given any processing.Therefore, the technology of needing a kind of novelty badly effectively solves the above-mentioned defective of prior art.
Summary of the invention
At the problems referred to above, the present invention aims to provide a kind of frequency offset correction technology of novelty, to eliminate the influence of frequency deviation in the LTE system effectively.
According to an aspect of the present invention, provide a kind of method that is used for frequency offset correction, having comprised: receive an initialize signal; And described initialize signal carried out initial channel estimation, channel estimating frequency domain filtering and channel estimating time-domain filtering successively, wherein, before described channel estimating time-domain filtering, the signal of channel being estimated frequency domain filtering carries out frequency offset estimating, then described channel is estimated that the signal of frequency domain filtering carries out frequency deviation and eliminates.Preferably, after described channel estimating time-domain filtering, signal and the described initialize signal of estimating time-domain filtering through signal carried out the MIMO detection.
According to a preferred embodiment, in said method, estimate that through signal the signal of time-domain filtering is reconstructed skew to described based on described frequency offset estimating; And to described initialize signal with carry out MIMO through the signal of reconstruct skew and detect.
According to another preferred embodiment, in said method,, described initialize signal is carried out skew eliminate based on described frequency offset estimating; And the described signal of eliminating through skew estimated that with channel the signal of time-domain filtering carries out the MIMO detection.
According to another preferred embodiment, in said method, channel is estimated that the signal of time-domain filtering and described initialize signal carry out the MIMO detection; And, the signal that detects through MIMO is carried out skew eliminate based on described frequency offset estimating.
According to a further aspect in the invention, provide a kind of system that is used for frequency offset correction, having comprised: a signal receiving device is used to receive an initialize signal; An and initial channel estimation device that connects from described signal receiving device signal successively, an one channel estimating frequency domain filtering device and a channel estimating time-domain filtering device, wherein, before described channel estimating time-domain filtering device, further comprise: a frequency deviation estimation device, receive the output of described channel estimating frequency domain filtering device, and the signal from the output of described channel estimating frequency domain filtering device carried out frequency offset estimating, an and frequency deviation cancellation element, receive the output of described channel estimating frequency domain filtering device and the output of described frequency deviation estimation device, and be used for eliminating, and will output to described channel estimating time-domain filtering device through the signal that frequency deviation is eliminated according to the signal from described channel estimating frequency domain filtering device output being carried out frequency deviation from the frequency offset estimation result of described frequency deviation estimation device output.Preferably, this system also comprises a MIMO checkout gear, receives signal and described initialize signal through described channel estimating time-domain filtering device output, detects to carry out MIMO.
According to a preferred embodiment, said system can also comprise a reconstruct phase deflection device, receive the output of described frequency deviation estimation device and the output of described channel estimating time-domain filtering device, output based on described frequency deviation estimation device is reconstructed skew to the signal from described channel estimating time-domain filtering device output, and will send to described MIMO checkout gear through the signal of reconstruct skew, wherein, described MIMO checkout gear carries out MIMO to described initialize signal and described signal through the reconstruct skew and detects.
According to another preferred embodiment, said system can also comprise a skew cancellation element, receive the output of described initialize signal and described frequency deviation estimation device, based on the output of described frequency deviation estimation device described initialize signal being carried out skew eliminates, and will send to described MIMO checkout gear through the signal that skew is eliminated, wherein, described MIMO checkout gear is to carrying out the MIMO detection from the signal of described skew cancellation element output with from the signal that described channel estimating time-domain filtering device is exported.
According to another preferred embodiment, said system can also comprise a skew cancellation element, receive the output of described MIMO checkout gear and the output of described frequency deviation estimation device, eliminate the signal from described MIMO checkout gear output is carried out skew based on the output of described frequency deviation estimation device.
Through check, method and system of the present invention can be eliminated the influence of frequency deviation effectively under various configurations.
Should be appreciated that the above generality of the present invention is described and the following detailed description all is exemplary and explanat, and be intended to the further explanation that the invention provides for as claimed in claim.
Description of drawings
Comprise that accompanying drawing is for providing the present invention further to be understood, they are included and are constituted the application's a part, and accompanying drawing shows embodiments of the invention, and play the effect of explaining the principle of the invention with this specification.In the accompanying drawing:
Fig. 1 is the schematic diagram of prior art.
Fig. 2 is a RS place initial channel estimation schematic diagram.
Fig. 3 is a channel estimating schematic diagram behind the frequency domain filtering.
Fig. 4 is the schematic diagram according to the first embodiment of the present invention.
Fig. 5 is a schematic diagram according to a second embodiment of the present invention.
Fig. 6 is the schematic diagram of a third embodiment in accordance with the invention.
Fig. 7 A-7F shows the comparison of the present invention and prior art under different condition.
Embodiment
Now with embodiments of the present invention will be described by referring to the drawings in detail.
According to general principle of the present invention, a kind of method that is used for frequency offset correction is provided, comprise receiving an initialize signal; And this initialize signal carried out initial channel estimation, channel estimating frequency domain filtering and channel estimating time-domain filtering successively, wherein before this channel estimating time-domain filtering, the signal of channel being estimated frequency domain filtering carries out frequency offset estimating, then this channel is estimated that the signal of frequency domain filtering carries out frequency deviation and eliminates.
As mentioned before, frequency deviation can cause the deviation of channel estimating and the deterioration of demodulation performance.Therefore, the present invention at first carries out frequency deviation to the channel estimating behind the frequency domain filtering and eliminates, and eliminates the frequency deviation in the channel estimation results.For example, the channel estimating after the correction is
Then
Channel estimating only has difference behind the frequency domain filtering when not having frequency deviation on noise item.Then, further to after proofreading and correct
Frequency domain channel estimates to do time-domain filtering, to obtain not contain the channel estimating of frequency deviation influence
On this basis, if being used for MIMO, the channel estimating after directly will proofreading and correct detects, though then eliminated the influence of frequency deviation in channel estimating, the influence of frequency deviation is not eliminated in the receiving symbol, therefore in the detected symbol phase deviation will still residually be arranged.For this reason, according to more preferably execution mode of the present invention, for thoroughly eliminating the influence of frequency deviation to detecting, can do phasing or the symbol after detecting is done phasing receiving symbol earlier, perhaps the phase effect that frequency deviation is caused be added on the channel estimating, promptly again
Wherein
Be the correction term of skew, make when detecting because received signal r
K, lWith same phase deviation is all arranged in the channel estimating, just no longer contain phase deviation in the final testing result.
Describe three different embodiment respectively in detail below in conjunction with accompanying drawing 4-6, so that technical scheme of the present invention is distincter based on above preferred implementation of the present invention.
First embodiment
Fig. 4 shows the first embodiment of the present invention.As shown in the figure, at first receive initial RS signal.Then, in frame 401, the RS signal is done channel estimating to obtain the channel estimation value at RS place.In frame 402, RS place channel estimation value is carried out frequency domain filtering, contain the channel estimation value at each subcarrier place of RS symbol with acquisition.
Compare with prior art shown in Figure 1, in this first embodiment of the present invention, at channel estimating time-domain filtering (frame 405) before, utilize channel estimating information that channel is estimated that the signal of frequency domain filtering carries out frequency offset estimating, obtain frequency offset estimating value (frame 403), utilize this frequency offset estimating value that the channel estimating of this channel estimation frequency domain filtering is calibrated to eliminate frequency deviation (frame 404) then.Therefore, the present invention can eliminate the influence of frequency deviation before time-domain filtering.
Then, in frame 405, the channel estimating behind the frequency domain filtering is done time-domain filtering, obtain the channel estimation value at all subcarrier places of all symbols.In frame 406, the channel estimating reconstructed phase deviation after utilizing the frequency offset estimating value to time-domain filtering is to obtain the channel estimation value that each subcarrier place has comprised phase deviation information.At last, in frame 407, utilize the channel estimating information after proofreading and correct that initial RS signal is done the MIMO detection, obtain the transmission sign estimation at each subcarrier place.
Second embodiment
Fig. 5 shows the second embodiment of the present invention.Frame 501-505 among Fig. 5 is corresponding with the 401-405 among Fig. 4, therefore repeats no more.Compare with above-mentioned first embodiment, the main distinction of present embodiment is that the Initial R S signal to another road carries out the skew elimination before carrying out the MIMO detection, and will be somebody's turn to do the signal of eliminating through skew and estimate that with channel the signal of time-domain filtering carries out MIMO and detects, and the step that has replaced the signal to channel estimation time-domain filtering among first embodiment to carry out skew reconstruct.Particularly, in frame 506, utilize the frequency offset estimating value that the Initial R S signal that receives is carried out phase deviation and eliminate, obtain the pending received signal that phase deviation has been eliminated at each subcarrier place.At last, in frame 507, utilize channel estimating information that the Initial R S signal after proofreading and correct is carried out MIMO and detect, obtain the transmission sign estimation at each subcarrier place.
The 3rd embodiment
Fig. 6 shows the third embodiment of the present invention.Frame 601-605 among Fig. 6 is corresponding with 401-405 and the 501-505 among Fig. 5 among Fig. 4, therefore repeats no more.Compare with above-mentioned first embodiment, the main distinction of present embodiment only is that after MIMO detects output signal being carried out skew eliminates, and has replaced the step of carrying out skew reconstruct among first embodiment before the MIMO detection.Particularly, in frame 606, utilize the channel estimating information after proofreading and correct that initial RS signal is done the MIMO detection, obtain the transmission sign estimation that each subcarrier place contains frequency deviation.In frame 607, utilize the frequency offset estimating value that the transmission sign estimation of output is done calibration, obtain the transmission sign estimation that phase deviation has been eliminated at each subcarrier place.
Comprehensive the foregoing description, the present invention can carry out frequency deviation to the channel estimating behind the frequency domain filtering and eliminate, and eliminates the frequency deviation in the channel estimation results.In addition, the present invention can perhaps do phasing to the signal after detecting by Initial R S signal is done phasing, and perhaps the phase effect that before detection frequency deviation is caused is added on the channel estimating again, comes the final influence of frequency deviation to detecting of thoroughly eliminating.
In addition, though above three embodiment are all described in the mode of step, each frame in the accompanying drawing also can be expressed as corresponding device thereof and constitute a complete system, and wherein arrow logo has gone out the trend that signal transmits.With Fig. 4 is example, and this Fig. 4 can represent a kind of system that is used for frequency offset correction equally, comprising: a signal receiving device is used to receive an initialize signal; And this signal receiving device initial channel estimation device 401 of connecting of signal successively certainly, an one channel estimating frequency domain filtering device 402 and a channel estimating time-domain filtering device 405, wherein, before this channel estimating time-domain filtering device 405, further comprise: a frequency deviation estimation device 403, receive the output of this channel estimating frequency domain filtering device 402, and the signal from 402 outputs of this channel estimating frequency domain filtering device carried out frequency offset estimating, an and frequency deviation cancellation element 404, receive the output of this channel estimating frequency domain filtering device 402 and the output of this frequency deviation estimation device 403, and be used for eliminating, and will output to this channel estimating time-domain filtering device 405 through the signal that frequency deviation is eliminated according to the signal from these channel estimating frequency domain filtering device 402 outputs being carried out frequency deviation from the frequency offset estimation result of these frequency deviation estimation device 403 outputs.In addition, this system also comprises a reconstruct phase deflection device 406 and a MIMO checkout gear 407.This reconstruct phase deflection device 406 receives the output of this frequency deviation estimation device 403 and the output of this channel estimating time-domain filtering device 405, output based on this frequency deviation estimation device 403 is reconstructed skew to the signal from these channel estimating time-domain filtering device 405 outputs, and will send to this MIMO checkout gear 407 through the signal of reconstruct skew.407 pairs of these initialize signals of this MIMO checkout gear and this signal through the reconstruct skew carry out MIMO and detect.Based on similar mode, Fig. 5 and Fig. 6 also can be respectively applied for expression according to two other system embodiment of the present invention.
At last, Fig. 7 A-7F show the present invention and prior art under different condition performance relatively.Because time domain estimates that the residue of frequency deviation is bigger, compared here when residual frequency departure is 100Hz, 300Hz under typical ETU channel, when single transmit antenna sends out that bandwidth is 10MHz under two reception antennas, the performance of new method and original method.
Among Fig. 7 A-7F, the curve that " non-calibration " expression is left intact to residual frequency departure, the curve that " calibration " expression is handled according to method of the present invention, the performance curve when " no frequency deviation " expression does not have frequency deviation, " SNR " represents signal to noise ratio, and " RawBER " represents the original error rate.Shown in Fig. 7 A-7F, frequency deviation has very big influence to receptivity, and promptly there is bigger skew in the curve of " non-calibration " with the curve of " no frequency deviation "; And method of the present invention has all obtained good performance under various residual frequency departure configurations, and is identical when it detects performance almost with no frequency deviation the situation of 64QAM during except 300Hz.
Those skilled in the art can be obvious, can carry out various modifications and variations and without departing from the spirit and scope of the present invention to above-mentioned exemplary embodiment of the present invention.Therefore, be intended to that the present invention is covered and drop in appended claims and the equivalence techniques scheme scope thereof to modification of the present invention and modification.
Claims (10)
1. method that is used for frequency offset correction comprises:
Receive an initialize signal; And
Described initialize signal is carried out initial channel estimation, channel estimating frequency domain filtering and channel estimating time-domain filtering successively,
Wherein, before described channel estimating time-domain filtering, channel is estimated the signal of frequency domain filtering carries out frequency offset estimating, then described channel is estimated that the signal of frequency domain filtering carries out frequency deviation and eliminates.
2. the method for claim 1 is characterized in that, after described channel estimating time-domain filtering signal and the described initialize signal of estimating time-domain filtering through signal is carried out the MIMO detection.
3. method as claimed in claim 2 is characterized in that,
Estimate that through signal the signal of time-domain filtering is reconstructed skew to described based on described frequency offset estimating; And
To described initialize signal with carry out MIMO through the signal of reconstruct skew and detect.
4. method as claimed in claim 2 is characterized in that,
Based on described frequency offset estimating, described initialize signal is carried out skew eliminate; And
Described signal and the channel of eliminating through skew estimated that the signal of time-domain filtering carries out MIMO and detects.
5. method as claimed in claim 2 is characterized in that,
Channel is estimated that the signal of time-domain filtering and described initialize signal carry out the MIMO detection; And
Based on described frequency offset estimating, the signal that detects through MIMO is carried out skew eliminate.
6. system that is used for frequency offset correction comprises:
One signal receiving device is used to receive an initialize signal; And
From an initial channel estimation device, a channel estimating frequency domain filtering device and a channel estimating time-domain filtering device of the connection of described signal receiving device signal successively,
Wherein, before described channel estimating time-domain filtering device, further comprise:
One frequency deviation estimation device receives the output of described channel estimating frequency domain filtering device, and the signal from described channel estimating frequency domain filtering device output is carried out frequency offset estimating, and
One frequency deviation cancellation element, receive the output of described channel estimating frequency domain filtering device and the output of described frequency deviation estimation device, and be used for eliminating, and will output to described channel estimating time-domain filtering device through the signal that frequency deviation is eliminated according to the signal from described channel estimating frequency domain filtering device output being carried out frequency deviation from the frequency offset estimation result of described frequency deviation estimation device output.
7. system as claimed in claim 6 is characterized in that, also comprises:
One MIMO checkout gear receives signal and described initialize signal through described channel estimating time-domain filtering device output, detects to carry out MIMO.
8. system as claimed in claim 7 is characterized in that, also comprises:
One reconstruct phase deflection device, receive the output of described frequency deviation estimation device and the output of described channel estimating time-domain filtering device, output based on described frequency deviation estimation device is reconstructed skew to the signal from described channel estimating time-domain filtering device output, and will send to described MIMO checkout gear through the signal of reconstruct skew
Wherein, described MIMO checkout gear carries out MIMO to described initialize signal and described signal through the reconstruct skew and detects.
9. system as claimed in claim 7 is characterized in that, also comprises:
One skew cancellation element receives the output of described initialize signal and described frequency deviation estimation device, and based on the output of described frequency deviation estimation device described initialize signal is carried out skew and eliminate, and will send to described MIMO checkout gear through the signal that skew is eliminated,
Wherein, described MIMO checkout gear is to carrying out the MIMO detection from the signal of described skew cancellation element output with from the signal that described channel estimating time-domain filtering device is exported.
10. system as claimed in claim 7 is characterized in that, also comprises:
One skew cancellation element receives the output of described MIMO checkout gear and the output of described frequency deviation estimation device, eliminates based on the output of described frequency deviation estimation device the signal from described MIMO checkout gear output is carried out skew.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009101949840A CN102006258A (en) | 2009-09-02 | 2009-09-02 | Method and system for correcting frequency deviation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009101949840A CN102006258A (en) | 2009-09-02 | 2009-09-02 | Method and system for correcting frequency deviation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102006258A true CN102006258A (en) | 2011-04-06 |
Family
ID=43813341
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009101949840A Pending CN102006258A (en) | 2009-09-02 | 2009-09-02 | Method and system for correcting frequency deviation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102006258A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103379059A (en) * | 2012-04-23 | 2013-10-30 | 马维尔国际有限公司 | Channel estimation method and device of mmse |
| CN106576086A (en) * | 2014-10-23 | 2017-04-19 | 华为技术有限公司 | Channel estimation method and apparatus |
| CN111865450A (en) * | 2019-04-29 | 2020-10-30 | 华为技术有限公司 | Method, device, equipment and storage medium for improving multi-user multiplexing performance |
-
2009
- 2009-09-02 CN CN2009101949840A patent/CN102006258A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103379059A (en) * | 2012-04-23 | 2013-10-30 | 马维尔国际有限公司 | Channel estimation method and device of mmse |
| CN106576086A (en) * | 2014-10-23 | 2017-04-19 | 华为技术有限公司 | Channel estimation method and apparatus |
| CN111865450A (en) * | 2019-04-29 | 2020-10-30 | 华为技术有限公司 | Method, device, equipment and storage medium for improving multi-user multiplexing performance |
| CN111865450B (en) * | 2019-04-29 | 2022-09-02 | 华为技术有限公司 | Method, device, equipment and storage medium for improving multi-user multiplexing performance |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101361307B (en) | Wireless communication device | |
| US10778496B2 (en) | OFDM system synchronization tracking method and apparatus | |
| US8085859B2 (en) | Platform noise mitigation | |
| CN101529766B (en) | Reception method and reception device | |
| CN105024791B (en) | The generation method of leading symbol in physical frame | |
| US7936844B2 (en) | Channel estimation apparatus with the optimal search and method thereof | |
| CN103609085B (en) | Apparatus and method for receiving signal in a wireless communication system | |
| CN104410590A (en) | Short-wave OFDM (Orthogonal Frequency Division Multiplexing) interference suppression joint channel estimation method based on compressed sensing | |
| US20130064277A1 (en) | Method, Apparatus and System for Antenna Calibration | |
| CN101692666B (en) | Method for filtering time domain channel response noises | |
| US20100046359A1 (en) | Wireless Terminal, Base Station and Channel Characteristic Estimating Method | |
| CN102006258A (en) | Method and system for correcting frequency deviation | |
| CN102687440B (en) | OFDM receiver,OFDM reception circuit,OFDM reception method | |
| JP2002330112A (en) | Ofdm digital signal repeater | |
| CN100574305C (en) | The signal-noise ratio estimation method and the device that shine upon based on planisphere in the multicarrier system | |
| CN101944977B (en) | Reception diversity method and system thereof | |
| CN112887249A (en) | Phase tracking method and system for WiFi service | |
| JP2010034934A (en) | Transmission channel estimation method and transmission channel estimator | |
| JP5146929B2 (en) | OFDM receiver | |
| CN102223336B (en) | Wireless communication method and equipment | |
| CN103095630B (en) | The method and apparatus that in wireless communication system, noise is estimated | |
| CN108347394B (en) | Multi-carrier communication system and channel estimation method thereof | |
| US20090274203A1 (en) | Measuring Method and Device for Evaluating an OFDM-Multi-Antenna Transmitter | |
| CN111181886A (en) | Frequency offset estimation method and device | |
| CN101702702B (en) | Symbol synchronizing method and device and symbol receiving processing system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20110406 |