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Simple sampling clock synchronisation scheme for reduced-guard-interval coherent optical OFDM systems

O. Omomukuyo, D. Chang, T.M.N. Ngatched, O.A. Dobre, R. Venkatesan
2015 Electronics Letters  
A simple data-aided scheme for sampling clock synchronisation in reduced-guard-interval coherent optical orthogonal frequency division multiplexing (RGI-CO-OFDM) systems is proposed.  ...  In the proposed scheme, the sampling clock offset (SCO) is estimated by using the training symbols reserved for channel estimation, thus avoiding extra training overhead.  ...  The proposed scheme does not require any additional hardware or training overhead and can compensate for up to the standard SCO of 200 ppm with low estimation error and negligible optical signal-to-noise  ... 
doi:10.1049/el.2015.3064 fatcat:wsy7laec4zbrbirflpifxktrva

Experimental demonstration of low-complexity fiber chromatic dispersion mitigation for reduced guard-interval OFDM coherent optical communication systems based on digital spectrum sub-band multiplexing

Mahdi Malekiha, Igor Tselniker, Moshe Nazarathy, Alex Tolmachev, David V. Plant
2015 Optics Express  
This enables compensation of both chromatic dispersion (CD) and polarization mode dispersion using a simple timing and one-tap-per-symbol frequency domain equalizer with a small cyclic prefix overhead.  ...  At the same total data rate and signal bandwidth both systems have similar performance and transmission reach whereas the proposed method allows for a significant reduction of computational complexity  ...  Consequently, rapid and accurate adaptive algorithms convergence means low data-aided overhead.  ... 
doi:10.1364/oe.23.025608 pmid:26480077 fatcat:vs6dfvm7gzb2dkj5iisycwia24

A FEC Architecture for UWB System

Sung-woo Choi, Sang-sung Choi, Han-ho Lee
2006 IEEE Vehicular Technology Conference  
In this paper, we show a detailed hardware architecture and implementation results of FEC (forward error correction) for the MB-OFDM UWB.  ...  The RS decoder is 27k gates and it can operate at a clock frequency of 232MHz, and has the latency of 46 symbol clocks.  ...  Total 31 OFDM symbols, which is the preamble, shall be added prior to data to aid the receiver in timing synchronization, carrier-offset recovery, and channel estimation. 1 1 1 2 3 1 2 3 2  ... 
doi:10.1109/vtcf.2006.309 dblp:conf/vtc/ChoiCL06 fatcat:igjjynklrvd6lbpmt576w5m2xq

Iterative Channel Estimation for the Chinese Digital Television Terrestrial Broadcasting Systems with the Multiple-Antenna Receivers

Zi Wei Zheng
2012 Advanced Engineering Forum  
hardware implementation, orthogonal frequency division multiplexing, so in the modern digital television terrestrial broadcasting the system is widely used to support high performance bandwidth-efficient  ...  Accurate channel estimation in a simple channel equalization and decoding of broadband multi-carrier orthogonal frequency division multiple-antenna receiver and channel estimation accuracy and multiplexing  ...  In the presence of phase noise, after completion of automatic gain control (AGC), signal detection, timing and frequency offset correction, the received signal ( ) effective composite channel frequency  ... 
doi:10.4028/ fatcat:6aq5q3yjp5aszdultrnti2whea

Behavior and Techniques for Improving Performance of OFDM Systems for Wireless communications
IJARCCE - Computer and Communication Engineering

Alcardo Alex Barakabitze, Md. Abbas Ali
2015 IJARCCE  
The research paper places a focus also on OFDM behaviors and techniques like Carrier Frequency Offset (CFO) estimation that improves performance of OFDM for wireless communications.  ...  Orthogonal frequency division multiplexing (OFDM) is a special case of multicarrier transmission which transmits a stream of data over a number of lower data rate subcarriers.  ...  B CARRIER FREQUENCY OFFSET ESTIMATION AND CORRECTION OFDM systems are affected by time and frequency varying wireless channels impairments.  ... 
doi:10.17148/ijarcce.2015.4152 fatcat:jhz6j5w5gjamrosklf4aj4ccda

Low-Overhead Low-Complexity Carrier Phase Recovery Technique for Coherent Multi-Band OFDM-Based Superchannel Systems Enabled by Optical Frequency Combs

Faith K. Deynu, Evans W. Akpari, Constant Akama
2021 Journal of Microwaves, Optoelectronics and Electromagnetic Applications  
The time-domain OFDM data is first generated using a MATLAB program with parameters as used for the simulation.  ...  After frequency offset compensation, we applied the proposed master-slave carrier phase tracking or an independent carrier phase recovery technique, both based on the pilot-aided carrier phase estimation  ... 
doi:10.1590/2179-10742021v20i1965 fatcat:bquosynbzrdqxgbl5nqzfdyxxu

Implementation and evaluation of channel estimation and phase tracking for vehicular networks

Yongjiu Du, Dinesh Rajan, Joseph Camp
2013 2013 9th International Wireless Communications and Mobile Computing Conference (IWCMC)  
The high mobility of vehicular networks makes channel estimation and phase tracking challenging and an important problem for OFDM receiver design.  ...  In this paper, we propose and implement a novel phase tracking algorithm, leveraging the decoded data.  ...  As a result, there is usually residual phase error for the OFDM symbols due to the residual carrier frequency offset, oscillator phase error, and channel variations.  ... 
doi:10.1109/iwcmc.2013.6583738 dblp:conf/iwcmc/DuRC13a fatcat:njpxroelaveivbia7jdezt4b64

Real world feasibility of interference alignment using MIMO-OFDM channel measurements

Omar El Ayach, Steven W. Peters, Robert W. Heath
2009 MILCOM 2009 - 2009 IEEE Military Communications Conference  
This paper presents the first experimental study of IA in measured interference channel and shows that IA achieves the claimed scaling factors in a variety of measured channel settings for a 3 user, 2  ...  Interference alignment (IA) has been shown to achieve linear sum capacity growth, at high SNR, with the number of users in the interference channel by cooperatively precoding transmitted signals to align  ...  This remaining frequency offset is then estimated and corrected in software [14] , and made possible by tight hardware synchronization.  ... 
doi:10.1109/milcom.2009.5379982 fatcat:ery3etil2bbf7n5onooyfhux4m

Timing and carrier synchronization in wireless communication systems: a survey and classification of research in the last 5 years

Ali A. Nasir, Salman Durrani, Hani Mehrpouyan, Steven D. Blostein, Rodney A. Kennedy
2016 EURASIP Journal on Wireless Communications and Networking  
Carrier synchronization is the process by which a receiver adapts the frequency and phase of its local carrier oscillator with those of the received signal.  ...  Timing synchronization is the process by which a receiver node determines the correct instants of time at which to sample the incoming signal.  ...  Accurate estimation and compensation of timing and frequency offsets from the PUs' signal is necessary to lead to the correct decision about the spectrum availability.  ... 
doi:10.1186/s13638-016-0670-9 fatcat:xqzvzx4trrgdnbw2sde5gjoisa

Optimum receiver design for OFDM-based broadband transmission .II. A case study

M. Speth, S. Fechtel, G. Fock, H. Meyr
2001 IEEE Transactions on Communications  
Special attention is paid to the OFDM-specific receiver functions necessary to demodulate the received signal and deliver soft information to the outer receiver for decoding.  ...  , carrier/sampling clock synchronization and channel estimation.  ...  Carrier and Sampling-Clock Synchronization In this section, we consider the carrier frequency offset and relative sampling frequency offset (signal models see Part I), with and the sampling duration offset  ... 
doi:10.1109/26.917759 fatcat:7cl3mzazd5cnhnmk22ov3xqiqa

Low overhead and nonlinear-tolerant adaptive zero-guard-interval CO-OFDM

Wei Wang, Qunbi Zhuge, Yuliang Gao, Meng Qiu, Mohamed Morsy-Osman, Mathieu Chagnon, Xian Xu, David V. Plant
2014 Optics Express  
offset and fiber nonlinearity.  ...  multiplexed ZGI CO-OFDM experiment with only 1% OFDM processing overhead.  ...  Improved SFO tolerance Sampling frequency offset between the transmitter and receiver has three effects on CO-OFDM systems: (1) ISI between neighboring OFDM symbols, (2) a time and frequency dependent  ... 
doi:10.1364/oe.22.017810 pmid:25089402 fatcat:63w7ohapkbegxgxz3iapkqr23m

Blind Transmitter Authentication for Spectrum Security and Enforcement

Vireshwar Kumar, Jung-Min Park, Kaigui Bian
2014 Proceedings of the 2014 ACM SIGSAC Conference on Computer and Communications Security - CCS '14  
Our evaluation of FEAT is based on theoretical bounds, simulations, and indoor experiments using an actual implementation.  ...  In this paper, we propose a novel BTA scheme called Frequency offset Embedding for Authenticating Transmitters (FEAT).  ...  A significant amount of work has been done in the field of blind (non-data-aided) parameter estimation, e.g., time and frequency offset estimation, for OFDM signals [12, 15, 23, 33] .  ... 
doi:10.1145/2660267.2660318 dblp:conf/ccs/Kumar0B14 fatcat:wodpxxzc75ew3gmlk5p4lootoq

Decision-Directed Fine Synchronization in OFDM Systems

K. Shi, E. Serpedin, P. Ciblat
2005 IEEE Transactions on Communications  
A new decision-directed (DD) synchronization scheme is proposed for joint estimation of carrier frequency offset (CFO) and sampling clock frequency offset (SFO) in orthogonal frequency-division multiplexing  ...  Index Terms-Carrier frequency offset (CFO), fast Fourier transform (FFT), orthogonal frequency-division multiplexing (OFDM), sampling clock frequency offset (SFO), synchronization.  ...  Numerous papers [1] - [4] deal with coarse frame (timing) and carrier frequency offset (CFO) synchronization, and most of them [2] - [4] proposed estimators before the fast Fourier transform (FFT  ... 
doi:10.1109/tcomm.2005.843463 fatcat:3tikjw4kebhktg54t4qckxmbae

An Intelligent Physical Layer For Cognitive Radio Networks

Aveek Dutta, Jeffrey Fifield, Graham Schelle, Dirk Grunwald, Douglas Sicker
2008 Proceedings of the 4th International ICST Conference on Wireless Internet  
In this paper, we discuss the evolution of an OFDM receiver, with sufficient software control to aid reconfigurability, capable of receiving and decoding information on different set of subcarriers, and  ...  The processing pipeline at an intermediate node no longer involves higher layer processing, and the hardware relays the incoming signal on-the-fly to a different part of the spectrum allowing for a full  ...  x(n − D) (1) Carrier Frequency Offset Correction Since the transmitter and the receiver clocks are powered by different crystal oscillators, there will always be an offset between the two.  ... 
doi:10.4108/icst.wicon2008.4984 dblp:conf/wicon/DuttaFSGS08 fatcat:ygu3wfeslfh4zihwpyotvg4l4y

A Survey on MIMO-OFDM Systems: Review of Recent Trends

Houda Harkat, Paulo Monteiro, Atilio Gameiro, Fernando Guiomar, Hasmath Farhana Thariq Ahmed
2022 Signals  
MIMO-OFDM is a key technology and a strong candidate for 5G telecommunication systems.  ...  The existing MIMO hardware and software innovations, in addition to the MIMO-OFDM equalization techniques, are discussed concisely.  ...  Acknowledgments: We would like to thank the editor and the reviewers for their comments which helped us improve the paper. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/signals3020023 fatcat:tsggpezrkracjodnwlmaf7x3iq
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