OFDM系统中的全数字频偏跟踪环
All Digital Frequency Offset Tracking Loop in OFDM Systems
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摘要: 频偏跟踪是影响到OFDM系统性能的关键技术之一。该文基于迟早门类型的锁相环，提出了一种新的适合于OFDM系统的频偏跟踪算法。研究表明，该算法既能在AWGN信道中也能在多径衰落信道中完成频偏跟踪工作。并且其低信噪比下的频偏跟踪性能比一般的频偏跟踪方法好几个数量级。如果系统对定时估计的要求不是特别高，该算法还能实现定时偏移和频率偏移的联合跟踪。Abstract: Frequency offset tracking is one of the key technologies that affect OFDM systems performance. Based on early-late gate phase-locked loop, a new frequency offset tracking algorithm is proposed in this paper. The study shows that the algorithm can complete frequency offset tracking in AWGN channel and multipath fading channel. Furthermore under lower SNR the performance of the proposed algorithm is better by several orders compared to the common frequency offset tracking methods. If the systems have not very special requirements on timing tracking this algorithm also can complete joint tracking of frequency and timing.
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Moose P H. A technique for orthogonal frequency division multiplexing frequency offset correction[月[J].IEEE Trans. on Commun.1994, 42(10):2908-2914[2]Van de Beek J J, Baorjesson P O. ML estimation of time and frequency offset in OFDM[J].IEEE Trans. on Signal Processing.1997, 45(7):1800-1805[3]Choi Y S, Voltz P J, Cassara F A. ML estimation of carrier frequency offset for multicarrier signals in Rayleigh fading channels[J].IEEE Trans. on Vehicular Technology.2001, 50(2):644-655[4]Liu H Tureli U. A high-efficiency carrier estimator for OFDM communications[J].IEEE Communication Letters.1998, 2(4):104-106[5]Luise M, Marselli M, Reggiannini R. Low-complexity blind carrier frequency recovery for OFDM signals over frequency-selective radio channels[J}]. IEEE Trans. on[6]Speth M, Fechtel S A, Fock G. Optimum receiver design for wireless broadband system using OFDM-Part I[J].IEEE Trans. on Commun.1999, 47(11):1668-1667[7]Speth M, Fechtel S A, Fock G. Optimum receiver design for OFDM-based broadband transmission-Part II: A case study[J].IEEE Trans. on Commun.2001, 49(4):571-578[8]Chen H, Pottie G J. A Comparison of frequency offset tracking algorithms for OFDM[A]. Globecom'2003[C]. San Francisco,USA, 2003: 1069-1073.[9]刘德良，王金龙.大频偏低信噪比条件下OFDM系统中的符号定时估计[J]电子与信息学报，2006, 28(4): 693-697.[10]Yang B G, Letaief K B, Cheng R S.OFDM transmission[J].IEEE Journal Timing recovery on Selected Areas Communications.2000, 18(11):2278-2291 -
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