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A Two-Stage Frequency-Offset Estimation Scheme for OFDMA System

Moh Mostafa, Abdel Fadeel Gamal, I. I. Ibrahim
2009 2009 3rd International Conference on New Technologies, Mobility and Security  
This paper reports a study of the carrier frequency offset (CFO) estimation and compensation in the uplink of the orthogonal frequency division multiple access (OFDMA) system with interleaved subcarrier  ...  error rate performance and has a relatively low implementation complexity.  ...  Two-stage CFO-estimation algorithm Considering the noise, a matrix form representation From Eq.(13), estimation of {θ ( m ) } M corresponds to of an OFDMA block is given by the m-th largest peaks of P  ... 
doi:10.1109/ntms.2009.5384825 dblp:conf/ntms/MostafaGI09 fatcat:oduc3fp6cbfyznrha3vivdigee

Efficient CFO Compensation Method in Uplink OFDMA for Mobile WiMax

Lakshmanan Muthukaruppan, Parthasharathi Mallick, Nithyanandan Lakshmanan, Sai Krishna Marepalli
2016 Journal of ICT Research and Applications  
Mobile WiMax uses Orthogonal Frequency Division Multiple Access (OFDMA) in uplink where synchronization is a complex task as each user presents a different carrier frequency offset (CFO).  ...  As estimation is done in the presence of noise, there exists some offset error, which is called residual frequency offset (RFO).  ...  Conclusion In this paper, an efficient CFO compensation technique in uplink OFDMA for mobile WiMAX was proposed.  ... 
doi:10.5614/itbj.ict.res.appl.2016.10.2.4 fatcat:klwejxvadzacld4ymax4q6gcpq

A reduced complexity scheme for carrier frequency synchronization in uplink 802.16e OFDMA

Javier González-Bayón, Angel Fernández-Herrero, Carlos Carreras
2012 EURASIP Journal on Advances in Signal Processing  
Synchronization of the carrier frequency offset (CFO) in the uplink of OFDMA systems is a complex task because each user presents a different CFO.  ...  It is performed in two stages: estimation and compensation.  ...  Conclusions A new frequency offset estimation scheme for the uplink of an 802.16e OFDMA system has been presented.  ... 
doi:10.1186/1687-6180-2012-218 fatcat:imw5t4zt4nd7zbd4b7vt63krxq

A novel PSO based carrier frequency offset estimation technique for Wi-MAX uplink transmissions

Fahad M. Al-Humaidan, P. P. Rahoof, S. M. Sameer
2011 2011 11th International Conference on Hybrid Intelligent Systems (HIS)  
Carrier frequency offset (CFO) estimation is a challenging task in Wi-MAX uplink as it uses orthogonal frequency division multiple access (OFDMA) which demands extremely accurate frequency synchronization  ...  In OFDMA uplink, each user may experience a different CFO relative to the base station reference carrier and the estimation of them turn out to be a multiple parameter estimation problem.  ...  Acknowledgments This work was done as part of a research project funded by King Faisal University, Al Ahsa, Kingdom of Saudi Arabia.  ... 
doi:10.1109/his.2011.6122137 dblp:conf/his/Al-HumaidanRS11 fatcat:xce5aqxnafeirdsleqn553dh3u

Detection of Interleaved OFDMA Uplink Signals in the Presence of Residual Frequency Offset Using the SAGE Algorithm

Jong-Ho Lee, Seong-Cheol Kim
2007 IEEE Transactions on Vehicular Technology  
Timing and frequency synchronization schemes for OFDMA uplink system have been studied in [2]- [7] .  ...  Then, the synchronization scheme in [2] estimates the timing and frequency offsets by repetition of the cyclic prefix (CP) [8] .  ...  ACKNOWLEDGMENT The authors would like to thank the paper editor and the reviewers for their valuable comments and suggestions.  ... 
doi:10.1109/tvt.2007.895574 fatcat:wd5pnekjn5g2hbe6qscv72j5dy

A Blind Iterative Carrier Frequency Offset Estimator Based On A Kalman Approach For An Interleaved Ofdma Uplink System

Guillaume Ferré, Eric Grivel, Hector Poveda, Pedro Ramos
2009 Zenodo  
Figure 7 shows our estimation algorithm robustness for tracking a variable CFO. The multiple frequency offsets also have been assumed varying between OFDMA symbols.  ...  FREQUENCY OFFSET ESTIMATION AND USER DETECTION In uplink OFDMA systems, the receiver performance is affected by CFO and MAI. In this section, a new method is proposed to mitigate both impacts.  ... 
doi:10.5281/zenodo.41692 fatcat:i3hzv6al2rd4xkypxnu4pkolse

An Interference-Cancellation Scheme for Carrier Frequency Offsets Correction in OFDMA Systems

D. Huang, K.B. Letaief
2005 IEEE Transactions on Communications  
In this paper, we present a scheme to compensate for the CFOs at the base station of an OFDMA system.  ...  In such systems, carrier frequency offsets (CFOs) can destroy the orthogonality among subcarriers.  ...  In this paper, we employ a two-stage approach to deal with the CFOs issue in OFDMA systems.  ... 
doi:10.1109/tcomm.2005.851558 fatcat:dfr2i2ck7bc53cu67rxdxsz5k4

Synchronization Techniques for Orthogonal Frequency Division Multiple Access (OFDMA): A Tutorial Review

Michele Morelli, C.-C. Jay Kuo, Man-On Pun
2007 Proceedings of the IEEE  
Even though the OFDMA concept is simple in its basic principle, the design of a practical OFDMA system is far from being a trivial task.  ...  This paper provides a comprehensive survey of the latest results in the field of synchronization for OFDMA systems, and the authors have endeavored to include ample tutorial content.  ...  Since the CFO is usually unknown at this stage, it is desirable that the timing recovery scheme be robust against possibly large frequency offsets.  ... 
doi:10.1109/jproc.2007.897979 fatcat:yclaxa734nd75l7v6ore6drzkq

A multiuser interference cancellation scheme for uplink OFDMA

S. Manohar, V. Tikiya, D. Sreedhar, A. Chockalingam
2006 IEEE Wireless Communications and Networking Conference, 2006. WCNC 2006.  
In uplink orthogonal frequency division multiple access (OFDMA) systems, multiuser interference (MUI) occurs due to different carrier frequency offsets (CFO) of different users at the receiver.  ...  We derive closed-form expressions for these optimum weights. The proposed LPIC scheme is shown to effectively cancel the MUI caused by the other user CFOs in uplink OFDMA.  ...  UPLINK OFDMA SYSTEM MODEL We consider an uplink OFDMA system with K users, where each user communicates with a base station through an independent multipath channel as shown in Fig. 1 .  ... 
doi:10.1109/wcnc.2006.1683574 dblp:conf/wcnc/ManoharTSC06 fatcat:g7s6vgjhifczppfatvox2n4hru

Cancellation of Multiuser Interference Due to Carrier Frequency Offsets in Uplink OFDMA

Shamaiah Manohar, Dheeraj Sreedhar, Vibhor Tikiya, A. Chockalingam
2007 IEEE Transactions on Wireless Communications  
In uplink orthogonal frequency division multiple access (OFDMA) systems, multiuser interference (MUI) occurs due to different carrier frequency offsets (CFO) of different users at the receiver.  ...  We derive closed-form expressions for these optimum weights. The proposed LPIC scheme is shown to effectively cancel the MUI caused by the other user CFOs in uplink OFDMA.  ...  It can be seen that for a given K, HLCC scheme is less complex for small N , whereas WLPIC scheme has lesser complexity than HLCC scheme for large N (which is typical in OFDMA systems).  ... 
doi:10.1109/twc.2007.05905 fatcat:xbmlk4fx2vbnpkwipnuxt4ersy

Cancellation of Multiuser Interference due to Carrier Frequency Offsets in Uplink OFDMA

S. Manohar, V. Tikiya, D. Sreedhar, A. Chockalingam
2006 2006 IEEE International Conference on Communications  
In uplink orthogonal frequency division multiple access (OFDMA) systems, multiuser interference (MUI) occurs due to different carrier frequency offsets (CFO) of different users at the receiver.  ...  We derive closed-form expressions for these optimum weights. The proposed LPIC scheme is shown to effectively cancel the MUI caused by the other user CFOs in uplink OFDMA.  ...  It can be seen that for a given K, HLCC scheme is less complex for small N , whereas WLPIC scheme has lesser complexity than HLCC scheme for large N (which is typical in OFDMA systems).  ... 
doi:10.1109/icc.2006.255373 dblp:conf/icc/ManoharTSC06 fatcat:xv7cfpp5jjcyjapasxoxdjarjy

Carrier frequency offset estimations in OFDM- downlink LTE systems

Patteti Krishna, Kalithkar Kishan Rao, Tipparti Anil Kumar
2015 2015 IEEE 9th International Conference on Intelligent Systems and Control (ISCO)  
The main goals of this paper is to understand the effects of frequency offset on OFDM systems and to present frequency offset estimation techniques so that we can correct for their effects.  ...  A complete carrier frequency offset estimation and compensation scheme based on standardized synchronization signals and reference symbols is presented.  ...  For smaller SNR presented three stage scheme is sufficient to compensate even relatively large CFOs in slow fading scenarios.  ... 
doi:10.1109/isco.2015.7282304 fatcat:5ghmjbooqzhp3fbawdjxt7cmte

Spectrally efficient waveforms for the return link in satellite communication systems

Svilen Dimitrov, Niccolo Privitera, Rosalba Suffritti, Gabriele Boccolini, Adegbenga B. Awoseyila, Barry G. Evans
2015 2015 European Conference on Networks and Communications (EuCNC)  
A globalpositioning-system-(GPS)-based approach for synchronization acquisition is proposed, while suitable algorithms are studied for timing/frequency offset estimation and synchronization tracking.  ...  These include orthogonal frequency division multiple access (OFDMA), single-carrier frequency division multiple access (SC-FDMA) and filter bank multi-carrier (FBMC).  ...  Tracking and estimation After synchronization is acquired, estimation of residual timing and carrier frequency offsets is used for fine synchronization and tracking.  ... 
doi:10.1109/eucnc.2015.7194030 dblp:conf/eucnc/DimitrovPSBAE15 fatcat:awx23yfbdne4film3raixgas7q

A novel initial ranging algorithm for OFDMA systems using smart antenna

YuJie Xia, GuangLiang Ren
2014 Science China Information Sciences  
A novel initial ranging algorithm for OFDMA systems using smart antenna.  ...  To improve the capacity of initial ranging (IR) users simultaneously accessing into network and enhance the performance of the IR, a novel IR algorithm is presented for the orthogonal frequency division  ...  The previously discussed schemes perform the IR procedure in the time or frequency domain for single-input single-output OFDMA systems.  ... 
doi:10.1007/s11432-014-5129-1 fatcat:juc2tcbxnraavp2n7rsymcjjdi

Uplink Synchronization in OFDMA Spectrum-Sharing Systems

Luca Sanguinetti, Michele Morelli, H. Vincent Poor
2010 IEEE Transactions on Signal Processing  
The resulting frequency estimator turns out to be the extension to a multiuser scenario of a scheme that has previously been proposed for single-user spectrum-sharing systems.  ...  This paper considers the uplink of an orthogonal frequency-division multiple-access (OFDMA)-based spectrum sharing system and provides solutions for estimating the frequency and timing errors of multiple  ...  At the BS, frequency and timing acquisition is achieved by means of a two-stage procedure that operates as follows.  ... 
doi:10.1109/tsp.2010.2041867 fatcat:fkbpcozyivgtfhkhj3zswp5chi
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