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44results about How to "Improve frequency offset estimation accuracy" patented technology
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OFDM/OQAM (Orthogonal Frequency Division Multiplexing/Offset Quadrature Amplitude Modulation) system and time frequency synchronization method thereof
InactiveCN102185822AHigh precisionIncrease catch rateMulti-frequency code systemsTransmitter/receiver shaping networksFrame sequenceCarrier frequency offset
The invention discloses an OFDM / OQAM (Orthogonal Frequency Division Multiplexing / Offset Quadrature Amplitude Modulation) system and a time frequency synchronization method thereof. The time frequency synchronization method comprises the following steps of: a coarse synchronization estimating step for estimating an estimated frequency offset value of a received baseband receiving signal frame sequence; a frequency offset compensating step for compensating the frequency offset of the received base band receiving signal frame sequence by using the estimated frequency offset value obtained by thecoarse synchronization estimating step; a fine synchronization estimating step for estimating an estimated time offset value of r2 (KTS) obtained by the frequency offset compensating step; and a timeoffset compensating step for compensating the time offset of the r2 (kTS) obtained by the frequency offset compensating step by using the estimated time offset value obtained by the fine synchronization estimating step so as to obtain r3 (kTS). In the invention, one-step synchronization is divided into two steps including coarse synchronization and fine synchronization; and the frequency offset of the baseband receiving signal frame sequence is first compensated by using the estimated frequency offset value obtained in the coarse synchronization and then the fine synchronization is carried out by using the compensated signal to obtain a final estimated time offset value so that the influence of CFO (Carrier Frequency Offset) during the fine synchronization is minimized and the time offsetestimation accuracy and the acquisition probability are improved.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA
OFDM carrier frequency offset estimation method suitable for packet transmission
InactiveCN101588338AImprove effectivenessImprove frequency offset estimation accuracyMulti-frequency code systemsTransmitter/receiver shaping networksTime domainEstimation methods
The invention provides an OFDM carrier frequency offset estimation method for packet transmission, which comprises the following steps: 1) performing IFFT conversion on frequency domain symbols to obtain time domain training symbols of two same repetition modules; 2) adding cyclic prefixes with the length of L on the front of the time domain training symbols to form integral OFDM symbols, and obtaining received OFDM signals carrying frequency offset epsilon through a multipath channel; 3) rotating phases with pi epsilon by N / 2 spaced received sample values in the received OFDM signals to obtain fine frequency offset estimation epsilon [fine]; 4) performing fine frequency offset compensation on the received OFDM signals to obtain OFDM signals after the compensation; 5) performing FFT conversion on training symbol parts of the compensated OFDM symbols after the cyclic prefixes are removed so as to obtain receiving end modulation frequency domain symbols; 6) detecting peaks of cyclic shift of the receiving end frequency domain symbols and sending end frequency domain symbols to obtain coarse frequency offset estimation; and 7) performing coarse frequency offset compensation on the receiving end modulation frequency domain symbols in a receiving end frequency domain, and summing up the coarse frequency offset estimation and the fine frequency offset estimation to obtain the carrier frequency offset estimation.
Owner:SHANDONG UNIV
Synchronizing method for orthogonal frequency division multiplex system
InactiveCN1988525ASimple structureReduce computationMulti-frequency code systemsEffective lengthComputer science
The invention discloses a synchronization method for orthogonal frequency division multiplexing system, including: the launcher firstly constructs the originated / synchronous sequence that is sent out with OFDM data symbols together. Based on the correlation of CP effective length in OFDM symbols form the receiving end, the correlation result conducts a time domain processing to the correlation sequence energy to get the best synchronization points set after one synchronization. Based on the originated sequence and CP, the departure estimation and departure compensation of fractional part DF several times are processed. During a range of synchronization points set output at once, the long pre-symbol received after the compensation is made time-domain correlation with the symbol to find the second time synchronization point. Then after time-domain of the short pre-symbol and the received pre-sequence is made frequency departure compensation, time-domain-related operations is conduct to get the DF departure estimation of integer times, and departure compensation is conduct.
Owner:ZTE CORP
Carrier frequency estimation method and apparatus in wireless communication system
InactiveUS20100128808A1Improving carrier frequency offset estimation accuracyImprove frequency offset estimation accuracySynchronisation arrangementAmplitude-modulated carrier systemsCommunications systemEstimation methods
A carrier frequency estimation method and apparatus is provided for improving frequency estimation performance in an Orthogonal Frequency Division Multiplexing (OFDM) communication system. The frequency estimation method for a wireless communication system includes summing correlations of four pairs of reference symbols transmitted at different frequency-time resource blocks in a pattern, each pair including two closest reference symbols; calculating a statistical value (E) by accumulating the summed correlation in a frequency direction; and estimating a frequency offset using an angle extracted from the statistical value (E).
Owner:SAMSUNG ELECTRONICS CO LTD
MIMO-OFDM system frequency deviation estimation method
InactiveCN105245484AImprove frequency offset estimation accuracyMulti-frequency code systemsTime domainEstimation methods
The invention relates to an MIMO-OFDM system frequency deviation estimation method. The method is used for performing frequency deviation estimation on signals which contain a short training sequence, a long training sequence and an SIG sequence and are received by a plurality of receiving antennas of the receiver of an MIMO-OFDM system. The method of the invention includes the following steps that: coarse frequency deviation is calculated through utilizing the short training sequence of the signals; long training sequence frequency deviation is calculated through utilizing the long training sequence of the signals; time-domain residual carrier frequency deviation is calculated through utilizing the SIG sequence; and the coarse frequency deviation, the long training sequence frequency deviation and the time-domain residual carrier frequency deviation are summated, and a summation result is adopted as the estimation result of carrier frequency deviation. The method has the advantages of high frequency deviation estimation accuracy and wide application range.
Owner:中科威发半导体(苏州)有限公司
Frequency synchronization method based on joint estimation of carrier frequency offset
InactiveCN102970271AFrequency synchronizationGood for adapting to scenarios with large frequency deviation fluctuationsMulti-frequency code systemsMean squareCarrier frequency offset
The invention relates to a frequency synchronization method based on joint estimation carrier of frequency offset, belonging to the technical field of wireless mobile communication. The frequency synchronization method comprises the steps of: carrying out coarse frequency synchronization by using a short training field so as to correct integer frequency offset and carrying out frequency offset compensation on the basis of a coarse frequency synchronization result; by using a signal subjected to frequency offset compensation and a long training field, in combination with a segmentation related algorithm, carrying out frequency estimation to obtain a carrier frequency offset 1; obtaining a carrier frequency offset 2 on the basis of an MMSE (Minimum Mean Square Error) criterion; further obtaining a carrier frequency offset 3 on the basis of a mean square error criterion, and giving frequency synchronization results in different wireless channel environments; and finally, on the basis of the frequency synchronization results, carrying out frequency offset correction on a received signal. According to the frequency synchronization method, the synchronization mean square error of a wireless system is greatly lowered and the synchronization precision is effectively improved.
Owner:BEIJING INSTITUTE OF TECHNOLOGYGY
Multicarrier synchronization method and system of nested recurrent PN sequence
ActiveCN106341361AGood carrier synchronizationReduce complexityMulti-frequency code systemsSignal-to-noise ratio (imaging)Carrier frequency offset
The invention discloses a multicarrier synchronization method and system of a nested recurrent PN sequence. According to the method, a carrier frequency offset estimation step and a frequency offset correction step are carried out successively, in the carrier frequency offset estimation step, the separated nested recurrent PN sequence is processed; and in the frequency offset correction step, the carrier frequency offset of a received signal is corrected. According to technical schemes of the invention, the method and device can be applied to the digital communication fields with low signal to noise ratio transmission and severe clutter interference, as ground wireless communication and satellite and power line communication.
Owner:HANGZHOU DIANZI UNIV
Method for implementing carrier frequency offset correction base on large-point FFT
ActiveCN109274623AHigh frequency resolutionImprove frequency offset estimation accuracyCarrier regulationFrequency spectrumLow-pass filter
A method for implementing carrier frequency offset correction base on large-point FFT. Firstly, the receive signal is orthogonally mixed, convert to I, Q two-way signal, and then combining the outputsignals of I and Q into complex signals, the spectrum characteristics of complex signals are estimated by using the twice FFT matrix method, and then finding the position corresponding to the maximumpeak point on the spectrum characteristic and calculating the frequency offset value, Finally, the frequency offset value is converted into the frequency control word of the voltage controlled oscillator, so as to generate the same frequency as the frequency offset value. After passing through the feedback loop, I and Q signals are compensated by orthogonal mixing, and the high-frequency components are eliminated through the low-pass filter to output the correct baseband signal after the frequency offset is eliminated.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA
Frequency offset estimation method and system for 32-system quadrature amplitude modulation signal
ActiveCN109246044AImprove frequency offset estimation accuracyGood signal-to-noise ratio threshold performanceMulti-frequency code systemsFrequency spectrumPeak value
The invention discloses a frequency offset estimation method and system for a 32-system quadrature amplitude modulation signal. According to the method and system, the method comprises the steps: rotating a class II signal sequence and a class IV signal sequence in a received 32-system quadrature amplitude modulation signal sequence in the same direction to form a rotation modulation signal sequence, and then using each amplification coefficient with the maximum peak-to-average power ratio for amplifying the rotation modulation signal sequence to obtain an amplified modulation signal sequence;performing the fast Fourier transform of the fourth power of the amplified modulation signal sequence based on the above, thereby obtaining the frequency corresponding to the peak of the spectrum amplitude; finally determining the frequency offset estimation value of the 32-system quadrature amplitude modulated signal sequence according to the frequency corresponding to the peak value of the spectrum amplitude. The method and system provided by the invention have high frequency offset estimation precision, good signal to noise ratio threshold performance, strong practicability and good application prospect.
Owner:TANGSHAN COLLEGE
Frequency offset estimation method and apparatus for burst-mode signal
ActiveCN105610755AImprove frequency offset estimation accuracyInhibition effectMulti-frequency code systemsSignal-to-noise ratio (imaging)VIT signals
The invention relates to a frequency offset estimation method and system for a burst-mode signal. The method comprises the steps of extracting pilot frequency information of each segment in a received burst frame to obtain at least two segments of initial pilot frequency sequences; according to the pilot frequency information of each segment of initial pilot frequency sequence and standard pilot frequency information, generating target pilot frequency sequences; carrying out phase angle obtaining processing on the target pilot frequency sequences to obtain phase angle sequences; segmenting the phase angle sequences and setting a spacing between each two adjacent phase angle sequences; and according to a difference of two adjacent phase angle values in the phase angle sequences, calculating a series of frequency offset estimated values. According to the scheme of estimating the frequency offset of the burst-mode signal, which is provided by the invention, under the condition that each segment of pilot frequency sequence in a burst sequence in short burst communication is relatively short, by processing each segment of pilot frequency sequence, frequency offset estimation can be carried out through utilizing multiple segments of pilot frequency information, and each segment of pilot frequency sequence is not requested to have an equal length, and thus, a frequency offset value of the short burst frame can be accurately estimated, and frequency offset estimation accuracy under the condition of a low signal-to-noise ratio can be improved.
Owner:SPACE STAR TECH CO LTD
Multilevel frequency offset estimation method based on FFT
ActiveCN106375257AEstimated range is largeReduce the minimum frequency resolutionMulti-frequency code systemsEstimation methodsCarrier frequency offset
The invention belongs to the technical field of communication, and relates to a multilevel frequency offset estimation method based on FFT. The method provided by the invention mainly comprises the following steps: setting carrier frequency offset estimation to multiple frequency offset estimation levels, which is characterized in that a lower extraction ratio corresponding to the frequency offset estimation increases with the increase of the frequency offset estimation levels; carrying out the frequency offset estimation starting from the first level frequency offset estimation, and calculating the frequency offset estimation result of each level before the frequency offset estimation level reaches a preset total level; and accumulating the frequency offset estimation result of each level, and using the obtained accumulated value as a final frequency offset estimation result. The multilevel frequency offset estimation method provided by the invention has the beneficial effects that compared with the traditional frequency offset estimation method based on the FFT, on the basis of guaranteeing the estimation range, the frequency offset estimation precision can be greatly improved.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA
Frequency deviation estimating method in QAM (quadrature amplitude modulation) communication system
ActiveCN102497339AImprove frequency offset estimation accuracyExpand the range of frequency offset estimationTransmitter/receiver shaping networksMultiple carrier systemsSignal-to-noise ratio (imaging)Quadrature modulation
The invention discloses a frequency deviation estimating method in the QAM (quadrature amplitude modulation). The frequency deviation estimating method is characterized by including steps of carrying out frame synchronization by means of relative detection and picking up frame header codes; pairwise corrugating and multiplying the frame header codes with the interval 32 for rough frequency deviation estimation,; then corrugating and multiplying two adjacent frame header codes in pairwise for fine frequency deviation estimation; and combining the rough frequency deviation estimation and the fine frequency deviation estimation to obtain accurate frequency deviation estimation. By the aid of the frequency deviation estimating method, high-order QAM modulation accuracy and frequency deviation estimating accuracy on the condition of low signal to noise ratio in the QAM communication system are effectively increased, and the frequency deviation estimating range is broadened.
Owner:安徽省菲特科技股份有限公司 +1
Frequency offset estimation method and device for orthogonal frequency division multiplexing (OFDM) communication system
ActiveCN102118348AImprove frequency offset estimation accuracyExpand the range of frequency offset estimationMulti-frequency code systemsTransmitter/receiver shaping networksTime domainCommunications system
The invention discloses a frequency offset estimation method for an orthogonal frequency division multiplexing (OFDM) communication system, which comprises the following steps of: extracting a frequency-domain original reference signal and a time shift parameter; obtaining a time-domain reference signal with cyclic time shift characteristics according to the frequency-domain original reference signal and the time shift parameter; transmitting the time-domain reference signal; receiving the time-domain reference signal; and extracting a time shift reference signal, and calculating an estimatedfrequency offset value according to the time-domain reference signal and the time shift reference signal. The invention also discloses a frequency offset estimation device for the OFDM communication system. By the method and the device, the frequency offset estimation accuracy in the OFDM communication system is improved, and a frequency offset estimation range in the OFDM system is widened.
Owner:COMBA TELECOM SYST CHINA LTD
Frequency offset estimation method and frequency offset estimation device
ActiveCN105991484AImprove frequency offset estimation accuracyAvoid the phenomenon of frequency offset flippingBaseband system detailsMulti-frequency code systemsEstimation methodsCyclic prefix
Embodiments of the invention disclose a frequency offset estimation method and a frequency offset estimation device. The method comprises the following steps: carrying out frequency offset estimation according to the repeatability of cyclic prefix CP to get a first frequency offset estimated value; getting at least one second frequency offset estimated value through a preset pilot pair, and getting a wide range of frequency offset estimated values to be chosen according to the at least one second frequency offset estimated value and preset operation rules; and getting an optimal frequency offset estimated value according to the first frequency offset estimated value, the wide range of frequency offset estimated values to be chosen and a preset range value.
Owner:ZTE CORP
Precise frequency offset estimation method for burst spread spectrum weak signal
ActiveCN111654308AIncrease frequency offset estimation capabilityImprove frequency offset estimation accuracyTransmissionAlgorithmCarrier frequency offset
The invention relates to a precise frequency offset estimation method for a burst spread spectrum weak signal, which comprises the following steps of: receiving an input signal for carrier frequency offset estimation; eliminating pseudo code information in the input signal according to P multi-path synchronous positions to obtain P receiving sequences for eliminating pseudo random codes; dividingthe receiving sequences into groups with a length of eta; separately carrying out pre-averaging processing on the grouped data with the length of eta; performing FFT with the length of L on the pre-averaged grouped data to obtain a discrete spectrum; and carrying out incoherent accumulation on the absolute value of the amplitude of the discrete spectrum to obtain S (k), finding a k value corresponding to the maximum spectral line in the S (k), and calculating a frequency offset estimation value. According to the method, the frequency offset estimation capability of weak spread spectrum signals is remarkably improved by collecting incoherent accumulated energy after multi-path signal frequency domain transformation, and meanwhile, the frequency offset estimation precision is improved through a grouping pre-averaging technology.
Owner:SHANGHAI INST OF MICROSYSTEM & INFORMATION TECH CHINESE ACAD OF SCI
Sampling frequency offset estimation method based on pilot frequency
ActiveCN107612857AImprove frequency offset estimation accuracyImprove estimation performanceMulti-frequency code systemsDigital subscriber lineSampling frequency offset
The invention provides a sampling frequency offset estimation method based on a pilot frequency, which can obtain a good estimation effect in such NG-DSL (Next Generation Digital Subscriber Line) environment with a high sub-carrier number and a high modulation level. Estimation accuracy, a convergence rate and algorithm stability are all greatly promoted.
Owner:SUN YAT SEN UNIV
Coding CPM signal frequency offset estimation and correction method based on waveform matching
ActiveCN111800364ASmall estimated varianceImprove frequency offset estimation accuracyMulti-frequency code systemsSignal waveFrequency spectrum
The invention discloses a coding CPM signal frequency offset estimation and correction method based on waveform matching, and relates to the technical field of wireless measurement and control communication. According to the invention, the frequency offset estimation of the CPM receiving signal is carried out by adopting a method of correlatively matching the channel coding frame header waveform with the receiving signal waveform. Compared with a traditional frequency offset estimation method based on FFT frequency spectrum characteristics, the frequency offset estimation performance closer tothe corrected Cramer-Rao bound and the higher convergence speed can be obtained, the method is very suitable for an incoherent coding CPM receiver sensitive to residual frequency offset, and the error code performance better than that of a traditional frequency offset correction method can be obtained.
Owner:INST OF ELECTRONICS ENG CHINA ACAD OF ENG PHYSICS
Carrier frequency estimation method and apparatus in wireless communication system
InactiveUS8355468B2Improve frequency offset estimation accuracyEasy to useSynchronisation arrangementAmplitude-modulated carrier systemsCommunications systemEstimation methods
A carrier frequency estimation method and apparatus is provided for improving frequency estimation performance in an Orthogonal Frequency Division Multiplexing (OFDM) communication system. The frequency estimation method for a wireless communication system includes summing correlations of four pairs of reference symbols transmitted at different frequency-time resource blocks in a pattern, each pair including two closest reference symbols; calculating a statistical value (E) by accumulating the summed correlation in a frequency direction; and estimating a frequency offset using an angle extracted from the statistical value (E).
Owner:SAMSUNG ELECTRONICS CO LTD
Rapid frequency offset estimation and compensation method and system based on burst communication
PendingCN114172771AImprove signal-to-noise ratioImprove frequency offset estimation accuracyCarrier regulationMulti-frequency code systemsControl theoryDiversity combining
The invention discloses a fast frequency offset estimation and compensation method and system based on burst communication, and the method comprises the steps: obtaining a first signal, extracting a frame header signal of the first signal, demodulating the frame header signal, and obtaining a demodulated frame header signal; carrying out diversity combination on the demodulated frame header signal to obtain a frame header signal after diversity combination; performing coarse frequency offset estimation based on FFT on the frame header signal after diversity combining to obtain a coarse frequency offset estimation value, and performing coarse frequency offset compensation on the first signal according to the coarse frequency offset estimation value to obtain a second signal; extracting a pilot signal of the second signal, and demodulating the pilot signal to obtain a demodulated pilot signal; and carrying out FFT-based fine frequency offset estimation on the demodulated pilot signal to obtain a fine frequency offset estimation value, and carrying out fine frequency offset compensation on the second signal according to the fine frequency offset estimation value. According to the invention, the signal-to-noise ratio can be effectively improved, and the frequency offset estimation precision can be effectively improved.
Owner:中科南京移动通信与计算创新研究院
Multi-carrier synchronization method and system for nested loop pn sequence
ActiveCN106341361BGood carrier synchronizationReduce complexityMulti-frequency code systemsSignal-to-noise ratio (imaging)Carrier frequency offset
The invention discloses a multicarrier synchronization method and system of a nested recurrent PN sequence. According to the method, a carrier frequency offset estimation step and a frequency offset correction step are carried out successively, in the carrier frequency offset estimation step, the separated nested recurrent PN sequence is processed; and in the frequency offset correction step, the carrier frequency offset of a received signal is corrected. According to technical schemes of the invention, the method and device can be applied to the digital communication fields with low signal to noise ratio transmission and severe clutter interference, as ground wireless communication and satellite and power line communication.
Owner:HANGZHOU DIANZI UNIV
Frequency offset estimation method and system for 32-ary quadrature amplitude modulation signal
ActiveCN109246044BImprove frequency offset estimation accuracyGood signal-to-noise ratio threshold performanceMulti-frequency code systemsFrequency spectrumPeak value
The invention discloses a frequency offset estimation method and system for 32-ary quadrature amplitude modulation signals. In the frequency offset estimation method and system provided by the present invention, first, the type II signal sequence and the type IV signal sequence in the received 32-ary quadrature amplitude modulation signal sequence are rotated in the same direction to form a rotation modulation signal sequence, and then the rotation modulation signal sequence is formed by using Each amplification factor with the largest peak-to-average power ratio amplifies the rotation modulation signal sequence to obtain the amplified modulation signal sequence; on this basis, fast Fourier transform is performed on the fourth power of the amplified modulation signal sequence, so that the spectrum amplitude can be obtained The frequency corresponding to the peak value; finally, the estimated value of the frequency offset of the 32-ary quadrature amplitude modulation signal sequence is determined according to the frequency corresponding to the peak value of the spectrum amplitude. The frequency offset estimation method and system provided by the invention have high frequency offset estimation accuracy, good signal-to-noise ratio threshold performance, strong practicability, and good application prospects.
Owner:TANGSHAN COLLEGE
A frequency offset estimation method and device for a burst signal
ActiveCN105610755BAccurately estimate the frequency offset valueImprove frequency offset estimation accuracyMulti-frequency code systemsEngineeringComputer science
Owner:SPACE STAR TECH CO LTD
A Synchronization Method of FBMC System Based on Zero Autocorrelation Code
ActiveCN106230761BImprove performanceSimplified Judgment CriteriaMulti-frequency code systemsData transmissionComputer science
Owner:CENT SOUTH UNIV
A Multi-stage Frequency Offset Estimation Method Based on fft
ActiveCN106375257BEstimated range is largeReduce the minimum frequency resolutionMulti-frequency code systemsEstimation methodsCarrier frequency offset
The invention belongs to the technical field of communication, and relates to an FFT-based multi-stage frequency offset estimation method. The main method of the present invention is as follows: the carrier frequency offset estimation is set to a plurality of frequency offset estimation series, and the feature is that the downsampling multiple corresponding to the frequency offset estimation increases with the increase of the frequency offset estimation series; The frequency offset estimation series starts to perform frequency offset estimation, and the frequency offset estimation results of each level are calculated before the frequency offset estimation series reaches the preset total number of series; the frequency offset estimation results of each level obtained in the steps are accumulated, and the obtained The accumulated value is used as the final frequency offset estimation result. The beneficial effect of the invention is that, compared with the traditional frequency offset estimation method based on FFT, the invention can significantly improve the frequency offset estimation precision on the basis of ensuring the estimation range.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA
Frequency synchronization method based on joint estimation of carrier frequency offset
InactiveCN102970271BFrequency synchronizationGood for adapting to scenarios with large frequency deviation fluctuationsMulti-frequency code systemsMean squareCarrier frequency offset
Owner:BEIJING INSTITUTE OF TECHNOLOGYGY
OFDM carrier frequency offset estimation method suitable for packet transmission
InactiveCN101588338BImprove effectivenessImprove frequency offset estimation accuracyMulti-frequency code systemsTransmitter/receiver shaping networksTime domainEstimation methods
The present invention provides an OFDM carrier frequency offset estimation method for packet transmission, which comprises the following steps: 1) performing IFFT conversion on frequency domain symbols to obtain time domain training symbols of two same repetition modules; 2) adding cyclic prefixes with the length of L on the front of the time domain training symbols to form integral OFDM symbols, and obtaining received OFDM signals carrying frequency offset epsilon through a multipath channel; 3) rotating phases with pi epsilon by N / 2 spaced received sample values in the received OFDM signals to obtain fine frequency offset estimation; 4) performing fine frequency offset compensation on the received OFDM signals to obtain OFDM signals after the compensation; 5) performing FFT conversion on training symbol parts of the compensated OFDM symbols after the cyclic prefixes are removed so as to obtain receiving end modulation frequency domain symbols; 6) detecting peaks of cyclic shift of the receiving end frequency domain symbols and sending end frequency domain symbols to obtain coarse frequency offset estimation; and 7) performing coarse frequency offset compensation on the receiving end modulation frequency domain symbols in a receiving end frequency domain, and summing up the coarse frequency offset estimation and the fine frequency offset estimation to obtain the carrier frequency offset estimation.
Owner:SHANDONG UNIV
Decoding method and device for uplink control channel
InactiveCN106817332BImprove frequency offset estimation accuracyReduce performance lossSpatial transmit diversitySignal allocationDecoding methodsControl channel
The invention provides an uplink control channel decoding method and an uplink control channel decoding device. The method comprises the following steps: frequency offset pre-compensation is made for frequency domain data based on historical frequency offset values; predicted control information bits are obtained through decoding; the sender data symbol is reconstructed, and the frequency offset residual error is calculated; whether a first ratio is greater than or equal to a preset threshold is judged; if the first ratio is greater than or equal to the preset threshold, historical frequency offset values for next pre-compensation is updated, and the predicted control information bits are valid; and if the first ratio is not greater than or equal to the preset threshold, the historical frequency offset values and the frequency offset residual error do not affect the historical frequency offset values for next pre-compensation of user equipment UE, and the predicted control information bits are invalid. The influence of wrong historical frequency offset values on subsequent control information bits and historical frequency offset values for next pre-compensation is avoided. The timeliness and effectiveness of historical frequency offset values are maintained as much as possible. By updating the historical frequency offset values according to the frequency offset residual error to make next pre-compensation, the accuracy of frequency offset estimation can be improved. The performance loss can still be reduced when the frequency offset is close to the theoretical limit.
Owner:BEIJING XINWEI TELECOM TECH
Frequency offset estimation method and device for orthogonal frequency division multiplexing (OFDM) communication system
ActiveCN102118348BImprove frequency offset estimation accuracyExpand the range of frequency offset estimationMulti-frequency code systemsTransmitter/receiver shaping networksTime domainCommunications system
The invention discloses a frequency offset estimation method for an orthogonal frequency division multiplexing (OFDM) communication system, which comprises the following steps of: extracting a frequency-domain original reference signal and a time shift parameter; obtaining a time-domain reference signal with cyclic time shift characteristics according to the frequency-domain original reference signal and the time shift parameter; transmitting the time-domain reference signal; receiving the time-domain reference signal; and extracting a time shift reference signal, and calculating an estimatedfrequency offset value according to the time-domain reference signal and the time shift reference signal. The invention also discloses a frequency offset estimation device for the OFDM communication system. By the method and the device, the frequency offset estimation accuracy in the OFDM communication system is improved, and a frequency offset estimation range in the OFDM system is widened.
Owner:COMBA TELECOM SYST CHINA LTD
Method, device and system for estimating frequency offset in OFDM system
ActiveCN109691050BHigh precisionImprove practicalityMulti-frequency code systemsTelecommunicationsCarrier signal
Disclosed are a frequency offset estimation method, apparatus and system in an OFDM system. The method involves receiving an orthogonal frequency division multiplexing signal, wherein the orthogonal frequency division multiplexing signal contains zero sub-carriers periodically set in a frequency domain space; and according to control information about the orthogonal frequency division multiplexing signal, establishing a signal matrix, and finally obtaining the frequency offset estimation value by observing and calculating the signal matrix. The orthogonal frequency division multiplexing signal is a signal periodically separated in a comb-shaped manner by zero sub-carrier groups, so that interference between sub-carriers is effectively reduced; a large number of sub-carriers may be included in a data range for frequency offset estimation so as to expand the observation dimension, and thus, by means of observation and calculation of a large amount of data, frequency offset estimation precision is guaranteed. In addition, during observation and calculation, by using a layer by layer observation method, each layer of observation and calculation has a rational data processing complexity and approaches a highly precise calculation result layer by layer. The present invention is highly precise and highly applicable.
Owner:HUAWEI TECH CO LTD
Frequency Offset Estimation Method for Burst Signals with High Dynamic Frequency and Large Frequency Offset
InactiveCN104852875BDoppler frequency offset adaptabilityIncreased frequency offset search rangeTransmitter/receiver shaping networksData segmentCarrier signal
The present invention provides a frequency offset estimation method for burst signals with high dynamic and large frequency offset, including burst frame capture, Doppler change rate estimation and correction, basic frequency offset estimation and Doppler frequency offset estimation, burst signal frame It is composed of a pilot frequency segment and a data segment, and the receiver uses the pilot frequency segment to realize frequency offset estimation. First, the burst frame capture is realized by the threshold comparison method; then the pilot data is segmented, and the Doppler change rate is estimated by a DFT-assisted hierarchical iterative method, and the Doppler change rate estimate is used for the dynamics of the pilot segment Compensation; then, DFT-assisted basic frequency offset estimation is performed on the dynamically corrected signal; finally, the frequency offset of each symbol in the burst signal frame is jointly estimated by combining the estimated value of the Doppler change rate and the estimated value of the basic frequency offset. The data segment is compensated by using the frequency offset estimation result, so that the data segment has a small frequency change rate and residual frequency offset, which facilitates the realization of bit synchronization, frame synchronization and carrier synchronization.
Owner:中国人民解放军理工大学通信工程学院卫星通信军队重点实验室
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