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Robust channel estimation for the OFDM-based WLAN systems with imperfect synchronization

Zi-Wei Zheng
2007 Wireless personal communications  
In this paper, a robust channel estimation scheme is proposed for the OFDM-based WLAN systems with imperfect synchronization.  ...  As an effective technique for combating multipath fading and for high data rate transmission over wireless channels, orthogonal frequency division multiplexing (OFDM) is extensively used in wireless local  ...  In Sect. 3, robust channel estimation scheme is proposed for the OFDM-based WLAN systems with imperfect timing and frequency offset estimation. In Sect. 4, performance analysis is provided.  ... 
doi:10.1007/s11277-007-9275-2 fatcat:5irg5phwwzfu7lmd3bfcniyaqy

Deterministic Pilot Pattern Placement Optimization for OFDM Sparse Channel Estimation

Yang Nie
2020 IEEE Access  
Compressed sensing (CS) technologies have been widely adopted to pilot-assisted orthogonal frequency division multiplexing (OFDM) sparse channel estimation.  ...  We consider the design of the deterministic OFDM pilot pattern for solving a combinatorial optimization problem.  ...  CHANNEL ESTIMATION MODEL AND PROBLEM FORMULATION A. CHANNEL ESTIMATION MODEL The traditional pilot-assisted channel estimation employs LS algorithm in OFDM systems.  ... 
doi:10.1109/access.2020.3007916 fatcat:j3vtaaz3dfgvrjxrs23xf2q7oq

A Joint Timing Offset and Channel Estimation Using Fractional Fourier Transform and Cazac Sequences

Cherif Rezgui, Khaled Grayaa
2016 International Journal of Computer Networks & Communications  
This paper deals with symbol timing offset and channel estimation in OFDM (orthogonal frequency division multiplexing) system in fast varying channel.  ...  This method gives good results in terms of MSE in comparison with other known techniques, it estimated well the channel and it is important for fast varying channel.  ...  LS with DFT channel estimator is used with linear interpolation.  ... 
doi:10.5121/ijcnc.2016.8212 fatcat:xgoanofhgzcovfelfxop3duo2a

Iterative Channel Estimation Scheme for the WLAN Systems with the Multiple-Antenna Receivers

Zi Wei Zheng
2012 Advanced Engineering Forum  
In this article, the iterative channel estimation scheme proposed multi-carrier orthogonal frequency division multiplexed using multiple antennas receiver-based WLAN system.  ...  High-precision channel estimation scheme is very important wideband multi-carrier orthogonal frequency complex WLAN systems use multiple antenna receiver based division of labor and the overall multi-carrier  ...  The robustness of the channel estimation scheme is important for the application for the broadband multi-carrier OFDM systems with the multiple-antenna receiver and the accuracy of the channel estimation  ... 
doi:10.4028/ fatcat:oezy3gqyonfa3aixuehk4zmcse

Performance of Wireless OFDM System With LS - Interpolation-Based Channel Estimation In Multi-Path Fading Channel

A.Z.M. Touhidul Islam
2012 International Journal on Computational Science & Applications  
Matlab simulations are carried out to analyze the performance of the developed OFDM system with the employment of comb-pilot based channel estimation algorithms for various digital modulations in Rayleigh  ...  The LS, MMSE or Least Mean-Square (LMS) method can be used to estimate the channel at pilot frequencies, while different interpolation schemes are introduced for the channel estimation at data frequencies  ...  rotation estimates for each received symbol and facilitates their compensation.  ... 
doi:10.5121/ijcsa.2012.2501 fatcat:edi3jlxg25fupj4a4vfuguwbhm

Low-Complexity Sampling Frequency Offset Estimation and Compensation Scheme for OFDM-Based UWOC System

Hu Li, Tianyang Chen, Zhijie Wang, Bingyao Cao, Yingchun Li, Junjie Zhang
2022 Photonics  
The phase shift is obtained by simple multiplication for phase-conjugated pilots, and the results are averaged to perform more accurate phase estimation.  ...  In this paper, a simple sampling frequency offset (SFO) estimation and compensation scheme based on two phase-conjugated pilots is proposed and experimentally demonstrated in an OFDM-based underwater wireless  ...  Unlike traditional pilot-aided schemes utilizing the least square (LS) method to fit the SFO slope curve, the proposed scheme utilizes two phase-conjugated pilots for SFO estimation in each OFDM frame  ... 
doi:10.3390/photonics9040216 fatcat:huc2dcixzbhdjcvpojk5yng6kq

FPGA implementation of an OFDM-based WLAN receiver

María José Canet, Javier Valls, Vicenç Almenar, José Marín-Roig
2012 Microprocessors and microsystems  
Abstract: This paper deals with the design and implementation on FPGA of a receiver for OFDM-based WLAN. The circuit is particularized for IEEE 802.11.a,g standards.  ...  The system includes frame detection, time and frequency synchronization, demodulation, equalization and phase tracking.  ...  To avoid this, the rotation must be estimated and compensated for each OFDM symbol, which is known as phase tracking.  ... 
doi:10.1016/j.micpro.2011.11.004 fatcat:2n3kasqx5jcgdlwckuauerllbe

Low-complexity adaptive channel estimation for MIMO-OFDM systems over rayleigh fading channels

S. Abolfazl Hosseini, Sayed A. Hadei
2013 2013 1st International Conference on Communications, Signal Processing, and their Applications (ICCSPA)  
In this paper, we propose novel low-complexity adaptive scheme infrequency domain for estimation of MIMO-OFDM channels.Computational complexity of recursive least square (RLS)estimation algorithm is reduced  ...  Simulation results demonstrate the usefulness of the proposed scheme for MIMO-OFDMchannel estimation.  ...  The authors gratefully acknowledge for their financial and other supports.  ... 
doi:10.1109/iccspa.2013.6487328 fatcat:2jky5y7zkvf5hcqtia7hacbstu

Channel estimation for OFDM systems based on comb-type pilot arrangement in frequency selective fading channels

Meng-Han Hsieh, Che-Ho Wei
1998 IEEE transactions on consumer electronics  
In this paper, the channel estimation methods for OFDM systems based on comb-type pilot sub-carrier arrangement are investigated.  ...  The pilot signal estimation based on LS or MMSE criteria, together with channel interpolation based on piecewise-linear interpolation or piecewise second-order polynomial interpolation is studied.  ...  Phase compensated interpolation For a realistic OFDM system, the frame position error will affect the channel estimation.  ... 
doi:10.1109/30.663750 fatcat:p7sd37pgu5cjlijj6fkmyq4adu

A Hybrid of BFO and MCS Algorithm for Channel Estimation of MIMO-OFDM System

Dr. Manjith R
Then, for a given pilot placement obtained by the HBFOMCS algorithm, the MSE of least squares (LS) and Minimum Mean Square Error(MMSE) based channel estimation are computed.  ...  Simulation results indicate that, the proposed pilot symbol design provides better channel estimate MSE as well as the bit error rate (BER) performance with reduced computational complexity for MMSE method  ...  symbols, due to the phase rotation and amplitude attenuation caused by the channel.  ... 
doi:10.17148/ijireeice.2015.31010 fatcat:7aairb6h7jhidmrpaxfsyz2clm

Robust carrier frequency offset estimation for OFDM systems in doppler shift channels

Jinyong Choi, Jongseob Baek, Jongsoo Seo
2010 IEICE Electronics Express  
In this paper, a robust carrier frequency offset (CFO) estimation scheme is proposed for OFDM systems in Doppler shift channels.  ...  Using the TS, we then present maximum-Likelihood (ML) and averaging least square (LS) algorithms for performing acquisition and tracking steps of the CFO estimation.  ...  In this paper, methods are proposed for the robust CFO estimation for OFDM systems.  ... 
doi:10.1587/elex.7.1747 fatcat:qoc4xtyyl5g4xbenqu263srqsa

Channel Estimation for OFDM-Based WLANs in the Presence of Wiener Phase Noise and Residual Frequency Offset

2006 IEICE transactions on communications  
Simulation results present that the proposed scheme significantly improves the performance of OFDM-based WLANs. key words: orthogonal frequency-division multiplexing (OFDM), channel estimation, phase noise  ...  In this letter, we propose a combined pilot symbol assisted and decision-directed channel estimation scheme based on the leastsquares (LS) and the maximum-likelihood (ML) algorithms.  ...  Conclusion In this letter, we proposed a channel estimation scheme for OFDM-based WLANs.  ... 
doi:10.1093/ietcom/e89-b.5.1709 fatcat:vkjnuz7nzvhpzk6r2rk7lmdi2y


2018 Journal of Engineering Science and Technology  
In this paper, the channel between multiple antenna elements are investigated and analysed for optimum technique with less complexity and less power requirement to estimate the characteristics of the channel  ...  The bit error rate (BER) and normalised mean square error (NMSE) of the channels in MIMO-OFDM systems are examined for different channel tracking techniques.  ...  In the earlier phase of MIMO-OFDM system usage, pilot allocation methods that convert channel estimation of MIMO-OFDM into the channel estimation of SISO-OFDM were proposed generally.  ... 
doaj:013fc6aee44c404dac9867bf368fda6a fatcat:6omx6mbjyja67ag57lmboiiqwa

Joint Common Phase Error and Channel Estimation for OFDM-based WLANs in the Presence of Wiener Phase Noise and Residual Frequency Offset

Yong-hwa Kim, Jong-ho Lee, Seong-cheol Kim
2006 2006 IEEE International Conference on Communications  
Keywords-Orthogonal frequency-division multiplexing (OFDM), quadrature amplitude modulation (QAM), channel estimation, phase noise (PHN), wireless local area networks (WLANs). I.  ...  Then, data symbols and channel response including the CPE are estimated using the CPE estimator.  ...  INTRODUCTION Orthogonal frequency-division multiplexing (OFDM) has recently received considerable attention for its robustness against frequency selective channels.  ... 
doi:10.1109/icc.2006.255271 dblp:conf/icc/KimLK06 fatcat:njlf4q7mcjg33a4mniabpsheri

Superimposed training for PTS-PAPR reduction in OFDM: A side information free data recovery scheme

Guangtian Tan, Zhuyi Li, Jinli Su, Han Zhang
2013 2013 8th International Conference on Communications and Networking in China (CHINACOM)  
Based on superimposed training (ST), the combined channel response with the phase factors of PTS can be estimated within each interleaved PTS sub-block, and thus enables data recovery without the side  ...  In this paper, a side information free partial transmit sequence (PTS) technique is proposed to reduce the peak-toaverage power ratio (PAPR) for orthogonal frequency division multiplexing (OFDM) signals  ...  The aim of T-PTS is to find the optimum set of β m with respect to minimize the PAPR (2) of the phase rotated OFDM signal.  ... 
doi:10.1109/chinacom.2013.6694682 fatcat:7c3yachkq5d5ho2g7kunttznzm
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