Journal of East China Normal University(Natural Science) >
Sampling clock synchronization for OFDM based software-defined radio receivers
Received date: 2015-08-26
Online published: 2017-01-13
The sampling clock error in an OFDM (Orthogonal Frequency Division Multiplexing) receiver will severely degrade the overall system performance. Based on the canonical Gardner loop, a novel sampling clock synchronization scheme suitable for OFDM based software-defined radio (SDR) receivers is proposed, which uses a joint recursive algorithm to track the error and then corrects it by performing asynchronous resampling on the received signal. The proposed error detection method can improve estimation efficiency by eliminating effects of the carrier frequency error while sustaining the loop’s dynamic performance. A dynamic delay technique is devised to control the resampling process, which can smoothly adjust the incoming data stream without sampling disturbance. Theoretical analysis and simulation results indicate that the proposed scheme outperforms other techniques and works well in the multipath channel.
Key words: OFDM; SDR receiver; sampling clock synchronization; error detection; resampling
XIE Ying , HU Xing-bo , XU Wei-yang . Sampling clock synchronization for OFDM based software-defined radio receivers[J]. Journal of East China Normal University(Natural Science), 2016 , 2016(6) : 157 -165 . DOI: 10.3969/j.issn.1000-5641.2016.06.017
[ 1 ] HU X B, HUANG Y M, HONG Z L. Residual synchronization error elimination in OFDM baseband receivers [J]. ETRI Journal, 2007, 29(5): 596-606.
[ 2 ] XU W Y. Blind symbol timing estimation for orthogonal frequency division multiplexing based on non-Gaussianity maximization [J]. Wireless Personal Communications, 2014, 7(2): 865-881.
[ 3 ] LEE H, LEE J. Joint clock and frequency synchronization for OFDM-based cellular systems [J]. IEEE Signal Processing Letters, 2011, 18(12): 757-760.
[ 4 ] CHEN C, CHEN Y, DING N. Accurate sampling timing acquisition for baseband OFDM power-line communication in non-Gaussian noise [J]. IEEE Transactions on Communications, 2013, 61(4): 1608-1620.
[ 5 ] GARDNER F M. Interpolation in digital modems – part I: fundamentals [J]. IEEE Transactions on Communication, 1993, 41(3): 501-507.
[ 6 ] JOSE R, AMBAT S K, HARI K V S. Low complexity joint estimation of synchronization impairments in sparse channel for MIMO-OFDM system [J]. AEU-International Journal of Electronics and Communications, 2014, 68(2): 151-157.
[ 7 ] LIN Y T, CHEN S G. A blind fine synchronization scheme for SC-FDE systems [J]. IEEE Transactions on Communications, 2014, 62(1): 293-301.
[ 8 ] TSAI P Y, KANG H Y, CHIUEH T D. Joint weighted least-squares estimation of carrier-frequency offset and timing offset for OFDM systems over multipath fading channels [J]. IEEE Transactions on Vehicular Technology, 2005, 54(1): 211-223.
[ 9 ] SYLLAIOS I L, BALSARA P T. Linear time-variant modeling and analysis of all-digital phase-locked loops [J]. IEEE Transactions on Circuits and Systems I: Regular Papers, 2012, 59(11): 2495-2506.
[10] ETSI. ETSI TS 136 211 V910: Evolved Universal Terrestrial Radio Access (E-UTRA), Physical Channels and Modulation (Release 9) [S]. 2010: 4.
[11] CVETKOVIC Z, TAROKH V, YOON S. On frequency offset estimation for OFDM [J]. IEEE Transactions on Wireless Communications, 2013, 12(3): 1062-1072.
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