frequency offset

If the frequency offset is large enough, the traditional PLL cannot be locked. Such situation would lead to the system corruption.

After attaining synchronization, the phase offset due to frequency offset estimation error is tracked with a phase locked loop.

Frequency offset tracking is one of the key technologies that affect OFDM systems' performance.

However, one of the drawbacks of OFDM is the sensitivity to synchronization error, especially to frequency offset.

While in the meantime, OFDM has its own shortcomings: its sensitivity to a frequency offset and the high peak-to-average ratio.

This paper is focusing on study of NDA nonlinear least-squares(NLS) carrier frequency offset estimation for QAM signals.

The method provides integer frequency offset estimation, symbol timing estimation and fine frequency estimation, respectively.

Doppler frequency offset is always the passive factor that can't be neglected in satellite communication.

In the receiving side, the estimation of frequency offset and the synchronization are the two very important questions.

Frequency offset locking technology is widely applied in laser heterodyne detection and laser radar, which is of great value.

The combining unit combines frequency offset values assumed by the plurality of frequency offset assumption units.

In this thesis, synchronization algorithms of symbol timing and carriers frequency offset correction for OFDM are analyzed and researched.

The simulation results show that the scheme can estimate the carrier frequency offset accurately and is very simple to apply in practice.

Then influences of frequency offset and observation interval on symbol timing recovery system under this circumstance were studied.

Using two consecutive training symbols, a method for the joint estimation of fine timing and coarse frequency-offset is obtained.

Chapter six describes the timing and frequency offset compensation in uplink, which is the last step of the whole process.

The carrier frequency offset estimation algorithm and channel estimation algorithm are studied and implemented in this paper.

The moving vector of object can be confirmed when the acoustic-optic modulator (AOM) introduces a frequency offset.

then the frequency offset can be estimated grounded on the correlation of pilot symbols.

This paper mainly solves the problems of timing error and carrier frequency offset in the study of asynchronous cooperative communication.

A novel scheme of estimating the carrier frequency offset in CDMA system with the continuous pilot channel is proposed.

But if the Doppler frequency offset exceed the capture range of PLL, the carrier synchronization will fail.

According to this mode of receiver, the symbol timing error and the frequency offset can be estimated from a short preamble bits.

An algorithm suitable for carrier phase and frequency offset estimation in software radio is proposed.

This thesis deals with the algorithms of carrier frequency offset and phase error for MPSK signal.

This thesis focuses on the influence of frequency offset on GSM-R system, and the frequency estimation algorithm.

Then the phase trajectory is estimated based on MMSE criterion, and the frequency offset and initial phase can be achieved.

In addition, frequency offset estimation can be used to eliminate the ICI caused by the frequency offset.

The influence of the integral frequency offset is comprehensively analyzed in COOFDM system.

It is able to estimate the fractional part and integral part of frequency offset at the same time.

and generating (80) an estimated value of the carrier frequency offset from the integral common phase error.

OFDM system performance is more sensitive to frequency offset and timing error than single-carrier systems.

OFDM systems need special synchronizations to minimize the affect of timing error and frequency offset.

Then we discuss the influence of frequency offset on code loop in the noisy environment.

Second, the sensitivity of frequency offset and phase error.

However, OFDM is sensitive to frequency offset and phase noise.

It is robust in fast fading channel and lightly impacted by frequency offset.

Second, due to orthogonal sub-carriers, it is very sensitive to frequency offset.

Because of using the information of pilot, the frequency offset is estimated by a shorter CP. Therefore, the spending of system is reduced.

However, there are well-known shortcomings of OFDM technology: the timing offset and frequency offset is very sensitive.

frequency offset compensation is carried out using variable step size least mean square algorithm(VLMS).

For MQAM, the distribution of amplitude clusters was estimated, which was independent to the frequency offset.

Optimal correlation length of symbol timing and frequency offset estimation in OFDM systems

Novel Algorithm of Carrier Frequency Offset Estimation for Correlative Coded Orthogonal Frequency Division Multiplexing Systems

Analysis of the Effects of Carrier Frequency Offset in Orthogonal Frequency Division Multiplexing Systems

Coarse Decimal Frequency Offset Estimation and Its Adjustment in COFDM Demodulation

FPGA Implementation of Baseband Processing Algorithms for Satellite Spread Spectrum Signals with Large Frequency Offset

An effective iterative algorithm for carrier frequency offset estimate in an OFDM system

Study of Estimate Algorithm for Frequency Offset of Multiple Signal

Frequency-offset Synchronization and Channel Estimation for OFDM-Based Transmission system

Adaptive Frequency Offset Synchronization Algorithm for OFDM in Rayleigh Fading Channels

ESPRIT Based Implementation of Carrier Frequency Offset Estimation for Interleaved Multi-user OFDM

Frequency offset blind estimation over frequency-selective fading channels

Research of Data-Aided Carrier Frequency Offset Estimation Algorithms in Burst-Mode Transmission

A Pilot Subcarrier-based Joint Frequency Offset Correction and Channel Estimation Method for OFDM Systems

A Frequency Offset Correction Algorithm for Low-symbol-rate Satellite Communication System

Analysis of the Carrier Frequency Offset of Filterbank-based Multi-Modulation

Carrier frequency offset synthetic estimation for OFDM system in Wireless LAN environment

Analysis of Nonlinear Transformation in Frequency Offset Estimation for QAM Signals

Performance analysis of carrier frequency offset in multi-carrier spread spectrum system

An Algorithm for Rectifying Large Frequency-Offset in Fully Digitized QPSK Demodulation

The Estimation of the Coarse Frequency Offset and Timing in the Uplink Multiuser OFDM System

Real-time Estimation of Doppler Frequency Offset in LEO Mobile Satellite Communication

New OFDM frequency offset estimation method using repeated sequences and cyclic prefix

Effects of sampling frequency offset on satellite navigation receivers

The Algorithm of Ambiguity Function in Joint Estimation of Time Delay and Frequency Offset

Carrier frequency offset estimation algorithm of low complexity

Analysis and simulation of the frequency offset influence on FMT system

Frequency offset estimator for OFDM with time-frequency training sequence

A Frame Synchronization Method for Overcoming Frequency Offset in OFDM Systems

Performance comparison of achievable bit rate in FMT and OFDM system in the presence of frequency offset

Symbol Timing Estimation under Large Frequency Offset and Low Signal to Noise Ratio in OFDM Systems

Application of windowing in weaking the sensitivity of OFDM systems to frequency offset

Two Samples about Trouble Shooting Due to GSM System Frequency Offset

Pilot-assisted carrier frequency-offset estimation in smart antenna

Efficient timing and frequency offset estimation method for OFDM systems

Low-complex coarse frequency offset estimation algorithm in OFDM systems

Adaptive Time-Varying Frequency Offset Tracking Algorithm for OFDM

An Algorithm for Carrier Phase and Frequency Offset Estimation in Software Radio

Performance analysis and simulation of FMT system in the presence of frequency offset

Frequency Offset Estimation in the OFDM System Using Wavelets Transform

Blind estimation of frequency offset for GMSK modulation in fading channel

A Carrier Frequency Offset Estimation Algorithm for Uplink of OFDM Systems

Fine decimal frequency offset and sampling clock offset estimation in HDTV

A New OFDM Frequency Offset Estimation Method Using Repeated Sequences

A Novel Method of Frequency-Offset Estimation Using Scattered Pilots for OFDM System

A Novel Carrier Frequency Offset Estimation and Tracking Scheme for OFDM

A New Joint Estimation Algorithm of OFDM Carrier Frequency Offset and Phase Offset

The Research on the Algorithm of Dealing with Doppler Frequency Offset

Tone Phase Reversal Detection with Frequency-Offset Feed Back

Frequency-offset Locking of LD to Hyperfine Transition of cesium Atoms

An Iterative Receiver for OFDM Signal with Frequency Offset and Cochannel Interference

Blind Estimation of Frequency Offset and Symbol Timing Error

Sinusoid Frequency Estimation Method Based on Frequency Offset Correcting

All Digital Frequency Offset Tracking Loop in OFDM Systems

Combined Algorithm Based on FFT for Frame Synchronization and Frequency Offset Estimation

An Algorithm of Symbol Synchronization and Frequency Offset Estimation for OFDM Based on the Cost Function

Study on Pulse-to-Pulse Algorithmfor Measuring Acoustic Frequency Offset

ML estimation of integer frequency offset in OFDM systems

Joint Estimation of Sampling Clock and Residual Frequency Offset of OFDM System Based on Discrete Preamble

A Frequency Offset Estimation Algorithm based on Maximum Likelihood Estimator

Estimation of the reservoir permeability using the frequency offset and time lag of Stoneley wave

Robust Modulation Classification Algorithm Based on Higher-Order Cyclic Cumulants for SQAM Signals with Frequency Offset

The Frequency Offset Estimation Algorithm for OFDM Systems Based on Pilot Symbols and Decision Data

Estimation of frequency offset in DAB receiver

A Frequency Offset Estimator Based on Periodogram and Correlation Function

An Algorithm for Estimating Carrier Frequency Offset in the DSTM Based OFDM System

A New Efficient OFDM Frequency Offset Tracking Algorithm Based on Decision-directed

Adaptive frequency offset tracking algorithm for OFDM based on cyclic prefix

A Carrier Frequency Offset Estimation Algorithm for OFDM Based on Over-sample

A New Subspace Method of DOA Estimation with Four-Order Cumulants Based on Small Frequency Offset

A novel frequency offset estimation algorithm based on PN sequence

An algorithm for carrier recovery based on the false frequency offset

OFDM based on frequency offset estimation method

Joint Estimation of Time and Frequency Offset of OFDM in HF Channel

A Kind of Frequency Offset Estimation in OFDM Systems