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The effect of narrowband interference on ML fractional frequency offset estimator for OFDM

Mohamed Marey, Heidi Steendam
2006 Proceedings of the 2nd international conference on Mobile multimedia communications - MobiMedia '06  
In orthogonal frequency division multiplexing (OFDM) systems affected by carrier frequency offsets, the estimation of the frequency offset corresponding to a fractional part of the carrier spacing is a  ...  The proper action of the fractional frequency estimator can be strongly affected by the presence of disturbances, like narrowband interference (NBI) signals.  ...  CONCLUSIONS This paper evaluates the performance of ML fractional frequency estimator for OFDM system in the presence of narrowband interference for different interference parameters.  ... 
doi:10.1145/1374296.1374353 dblp:conf/mobimedia/MareyS06 fatcat:d5ghk275gfemjgju3bup6b5gh4

Analysis of the narrowband interference effect on frequency ambiguity resolution for OFDM systems

Mohamed Marey, Heidi Steendam
2009 Transactions on Emerging Telecommunications Technologies  
In orthogonal frequency division multiplexed (OFDM) systems affected by carrier frequency offsets, frequency ambiguity resolution, i.e. the estimation of the part of the frequency offset corresponding  ...  In this paper, the susceptibility of the blind and data aided maximum likelihood (ML) frequency ambiguity estimators to NBI signals, which may arise in the OFDM band as the spectrum becomes more crowded  ...  As the location of the interferer has nearly no effect on the performance of the blind estimator, the number of interferers has nearly no effect on the performance of the blind estimator.  ... 
doi:10.1002/ett.1273 fatcat:6formhmdubgwbgn5i7lxbkiid4

Synchronization for OFDM-Based Systems [chapter]

Yu-Ting Sun, Jia-Chin Li
2011 Recent Advances in Wireless Communications and Networks  
The authors have made every effort to systematically organize the information on these topics to make it easily accessible to readers of any level.  ...  Hard cover, 454 pages Publisher InTech This book focuses on the current hottest issues from the lowest layers to the upper layers of wireless communication networks and provides â€oereal-time†research  ...  The estimator (Lin, 2003) Because the effect of fast channel fading is considered here, the proposed technique has to account for a maximum Doppler frequency f D on the same order of 1/T u .  ... 
doi:10.5772/24690 fatcat:ovkxmvfdgbhffho62nmvywaqqm

RF Impairments in Wireless Transceivers: Phase Noise, CFO, and IQ Imbalance – A Survey

Amirhossein Mohammadian, Chintha Tellambura
2021 IEEE Access  
These impairments introduce in-band and out-of-band interference terms and degrade the performance of wireless systems.  ...  Moreover, we review RF-impairment estimation and compensation in singlecarrier (SC) and multicarrier systems, especially orthogonal frequency division multiplexing (OFDM).  ...  Thus, [307] addresses the joint estimation of frequency-selective channel and CFO in the presence of timing offset based on the ML criterion.  ... 
doi:10.1109/access.2021.3101845 fatcat:ete2cakeerdjrahum3gcuuexwe

A time and frequency synchronization scheme for multiuser OFDM

J.-J. van de Beek, P.O. Borjesson, M.-L. Boucheret, D. Landstrom, J.M. Arenas, P. Odling, C. Ostberg, M. Wahlqvist, S.K. Wilson
1999 IEEE Journal on Selected Areas in Communications  
We present a multiuser synchronization scheme for tracking the mobile's uplink time and frequency offsets. It uses the redundancy introduced by the cyclic prefix and does not need additional pilots.  ...  We show performance results of an orthogonal frequency division multiplexing (OFDM)-based radio interface based on universal mobile telecommunication system (UMTS) parameters.  ...  He emphasizes the interaction between models and real systems, from the creation of application-oriented models based on systems knowledge to the implementation and evaluation of algorithms.  ... 
doi:10.1109/49.806820 fatcat:ytzqt6gz7bbpvdao77avserzbe

On the Comparative Performance Analysis of Turbo-Coded Non-Ideal Sigle-Carrier and Multi-Carrier Waveforms over Wideband Vogler-Hoffmeyer HF Channels

F. Genc, M. A. Resat, A. Savascihabes, O. Ertug
2014 Radioengineering  
The purpose of this paper is to compare the turbo-coded Orthogonal Frequency Division Multiplexing (OFDM) and turbo-coded Single Carrier Frequency Domain Equalization (SC-FDE) systems under the effects  ...  of Carrier Frequency Offset (CFO), Symbol Timing Offset (STO) and phase noise in wide-band Vogler-Hoffmeyer HF channel model.  ...  Without CFO, the sub-channels do not interfere with one another. The impact of frequency offset is loss of orthogonality between the tones.  ... 
doaj:6eeaf629461448f8a3f180ea81f1e438 fatcat:enkahw5bxfb3vlelu2exr7gp7m

OFDM and Its Wireless Applications: A Survey

Taewon Hwang, Chenyang Yang, Gang Wu, Shaoqian Li, G. Ye Li
2009 IEEE Transactions on Vehicular Technology  
Orthogonal frequency-division multiplexing (OFDM) effectively mitigates intersymbol interference (ISI) caused by the delay spread of wireless channels.  ...  We address basic OFDM and related modulations, as well as techniques to improve the performance of OFDM for wireless communications, including channel estimation and signal detection, time-and frequency-offset  ...  By exploiting the repetitive property of the CP, a joint ML time synchronization and frequency-offset estimation has been proposed in [102] , and an optimal ML estimator and a minimum variance unbiased  ... 
doi:10.1109/tvt.2008.2004555 fatcat:6ix76lfrk5emhgozbhvdricj6m

Synchronization in Wireless Communications

Heidi Steendam, Mounir Ghogho, Marco Luise, Erdal Panayirci, Erchin Serpedin
2009 EURASIP Journal on Wireless Communications and Networking  
The link works at low SNR and uses forward error correction for data detection. Further, the incoming signal is disturbed by a large clock frequency offset.  ...  Besides of time synchronization, phase estimation of the RF carrier used for transmission is also crucial for coherent detection.  ...  the ML method, whereas the fractional frequency offset estimate is obtained from a correlation-based approach.  ... 
doi:10.1155/2009/568369 fatcat:52klthg37vgjxapa5iv45j366u

A Synchronization Design for UWB-Based Wireless Multimedia Systems

Zhenzhen Ye, Chunjie Duan, Philip V Orlik, Jinyun Zhang, Alhussein A Abouzeid
2010 IEEE transactions on broadcasting  
To mitigate the effect of narrowband interference (NBI) on UWB systems, we also propose a low-complexity ACF-based frequency detector to facilitate the design of (adaptive) notch filter in analog/digital  ...  To mitigate the effect of narrowband interference (NBI) on UWB systems, we also propose a low-complexity ACF-based frequency detector to facilitate the design of (adaptive) notch filter in analog/digital  ...  The narrowband interference (NBI) has been shown to have a big impact on the performance of OFDM systems [7] , [15] .  ... 
doi:10.1109/tbc.2010.2042499 fatcat:6srulvaicjgwdisf6nvsh3hztq

Timing and Frequency Synchronization for the Uplink of an OFDMA System

M. Morelli
2004 IEEE Transactions on Communications  
The frequency estimator is derived from ad hoc reasoning, whereas the timing estimator is based on the maximum-likelihood criterion. Both schemes rely on the repetition of a fixed pilot symbol.  ...  This paper deals with timing and frequency recovery for the uplink of an orthogonal frequency-division multiple access (OFDMA) system.  ...  Derivation of the Timing Estimator If the frequency offset were perfectly known, the ML timing estimator could be derived using the same arguments of Section IV to produce (37) where is computed setting  ... 
doi:10.1109/tcomm.2003.822699 fatcat:7kknkpllhncmvgglpri2faj2se

Channel Estimation based on Kalman Filtering with BER Reduction in MIMO-OFDM Systems

Amit Kapoor, Ishan Khurana
2014 International Journal of Computer Applications  
There are number of channel estimation methods which have already been proposed for MIMO-OFDM systems.  ...  MIMO-OFDM is one of the emerging communication schemes which provide efficient communication with multicarrier modulation.  ...  The other techniques which are Maximum Likelihood (ML) estimation and the Extended Kalman Filter (EKF) method statistically estimate the frequency offset and correct the offset using the estimated value  ... 
doi:10.5120/16971-6715 fatcat:ygrl2lin3zcrjpb7xqnjbd3hsu

ICI Reduction in Multicarrier Systems

Shaimaa ElSayed, K. A., Ragab M.
2016 International Journal of Computer Applications  
Keywords Orthogonal frequency division multiplexing (OFDM), channel estimation, Repeated Prefix (RP), inter-carrier interference (ICI), carrier frequency offset (CFO), Maximum Likelihood Estimation (MLE  ...  Inter-Carrier Interference (ICI) is a major contribution to performance degradation in multicarrier systems. The main reason of the ICI is the Carrier Frequency Offset (CFO).  ...  The main reason of the ICI is the Carrier Frequency Offset (CFO) that is generated as a result of Doppler Effect or the oscillators' instability used to generate the Radio Frequency (RF) carrier.  ... 
doi:10.5120/ijca2016908116 fatcat:agqlms77uffypgeuvnmuztnrgm

Compensation of Linear Multiscale Doppler for OFDM-Based Underwater Acoustic Communication Systems

A. E. Abdelkareem, B. S. Sharif, C. C. Tsimenidis, J. A. Neasham
2012 Journal of Electrical and Computer Engineering  
Additionally, the effects of weighting coefficients on smoothing the Doppler scale and on the performance of the receiver are also investigated.  ...  , based on the assumption that the speed changes linearly during the OFDM symbol time.  ...  In this technique, the fractional deviation of the subcarrier spacing, which is the source of ICI, is estimated by exploiting the fractional part of the normalized sampling frequency offset, whereas the  ... 
doi:10.1155/2012/139416 fatcat:d7n5z44qgrawhfyuaoidxhf7tq

University of Saskatchewan

1988 Canadian Institute of Food Science and Technology Journal  
Thus, it is necessary for the receiver to estimate and compensate for the frequency offset. Several high accuracy estimators are derived.  ...  In this thesis, the problems of data detection and channel and carrier frequency offset estimation in OFDM systems are studied.  ...  FDM offers an advantage over single-carrier modulation in terms of narrowband frequency interference since this interference will only affect one of the frequency sub-bands.  ... 
doi:10.1016/s0315-5463(88)70835-4 fatcat:a3l6i2zzufbpdamgtbjoaopvwq

University of Saskatchewan

1988 Canadian Institute of Food Science and Technology Journal  
Thus, it is necessary for the receiver to estimate and compensate for the frequency offset. Several high accuracy estimators are derived.  ...  In this thesis, the problems of data detection and channel and carrier frequency offset estimation in OFDM systems are studied.  ...  FDM offers an advantage over single-carrier modulation in terms of narrowband frequency interference since this interference will only affect one of the frequency sub-bands.  ... 
doi:10.1016/s0315-5463(88)70788-9 fatcat:sdupjczx7jfhrn63sthpxh6o6m
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