DTMB系统定时同步与频偏估计的算法研究
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摘要
数字电视的发展代表了一个国家数字化程度的高低,中国预计2015年完成模拟电视向数字电视的转换,地面数字电视的发展显得尤为重要,国际上主要有3种地面数字电视传输标准,美国的ATSC传输标准、欧洲的DVB-T传输标准以及日本的ISDB-T传输标准。中国于2006年8月颁布了中国地面数字电视传输标准(DTMB),地面数字电视发送端的调制和接收端的解调的实现迎来了新的挑战,国家标准的实施以及数字电视接收机的性能优化直接影响数字电视的发展,因此数字电视接收机内部芯片的算法设计是关键,影响接收机性能的主要三个模块是：解码,均衡和同步。
本文的主要工作在于研究和实现DTMB接收端系统的同步部分。本文首先简要介绍和比较了三大标准各自的优缺点,然后详细描述了DTMB系统的关键技术,包括星座映射、帧结构、TDS-OFDM系统等,重点分析了动态多径信道的特征,同步误差的产生原因以及对系统的影响。本文总结了国内外数字电视地面广播传输系统现有的定时恢复和频偏估计算法,提出存在的问题,发现在动态多径信道下算法研究的空间大,对于多径的处理也是一直以来研究的难点。
本文研究一种基于PN帧同步,采用延迟锁相环(DLL)和滑动相关技术的定时恢复的方案,并且为了提高在动态多径信道下定时误差估计的准确性,采用选取多径进行合成运算的方法,重点研究了多径信道下寄生峰、包络内假径和工作不稳定的问题以及解决办法,算法优化后仿真分析表明高Doppler的Rayleigh信道条件下,定时误差可以控制在+／-20ppm范围内。
在动态多径信道条件下频偏波动较大,难以进一步提高估计精度和扩大估计范围,本文综合考虑算法实现的复杂度,提出一种应用于国标数字电视DTMB系统频偏估计的算法改进。通过总结DTMB标准中相位旋转的初始相位的规律,修改相关计算的延迟长度和参与计算的数据长度,提高估计精度,达到频偏估计的多径合成效果。经仿真结果验证,该算法提高了动态多径信道下载波恢复模块工作的稳定性,延长了系统锁定时间,令具有高Doppler的多径信道的剩余频偏绕中心波动在正负10Hz以内,从而改善了DTMB系统频偏估计的性能。
The development of digital television represents the degree of a country's level of digital. The conversion of analogue TV to digital TV in China is expected to be completed by 2015. The development of terrestrial digital television is particularly important. Currently, there are three terrestrial digital TV transmission standards in the world. They are the U.S. ATSC, the European DVB-T and the Japan's ISDB. In August 2006, China formulated a standard named as DTMB(Digital TV terrestrial multimedia broadcasting),this brings about a certain challenges to the realization of terrestrial digital television's modulation and de-modulation. The implementation of national standard and the optimization of digital TV receiver performance directly affect the development of digital television, so the algorithm design of Digital TV receiver IP-chip is the key. There are three modules influenced the receiver performance. They are decoding, equalization and synchronization.
The main work of this thesis is to study and realize the synchronization of DTMB digital TV receiver. In this thesis, first we introduce and compare those three standards briefly, and we describe the main technology of DTMB system, including constellation mapping, framing structure, TDS-OFDM system and so on. We focus on analyzing the characteristics of the dynamic multipath channel, synchronization error causes and influences, and also sum up the domestic and international existing timing recovery and frequency offset estimation algorithm of digital television terrestrial broadcasting transmission system, discuss the problems in algorithm. We find that the research space in the dynamic multipath channel is huge. And the multi-path processing is also a research challenge.
In the thesis, we do some research on a timing recovery algorithm methodology based on PN-sequence frame synchronization, delay-locked Loop and sliding correlation technology. And in order to improve the accuracy of the timing error estimation in the dynamic multi-path channel, we synthesize different echoes correlation results; focus on the research of parasitic peak, pseudo echoes in the envelope and the instability. Computer simulation illustrates timing error can be controlled within the scope of+/-20ppm in the Rayleigh channel with high Doppler frequency.
For the low performance of frequency offset estimation module in the dynamic multi-path channel and the difficulty of improving the estimation accuracy and broadening the scope of frequency offset estimation, we proposed an algorithm of frequency offset estimation in DTMB System. The main research work is the discovery of the rules of preliminary phase of frame head in phase shift mode, and utilizing the rules to optimize the fluctuation of frequency offset in dynamic multi-path channel. We changed the delay length and data length in correlation. Computer simulation illustrates the superior performance of the proposed algorithm in the estimation accuracy and the stability of remaining frequency offset. The remaining frequency offset fluctuates within+/-10Hz in high-Doppler multi-path channel, thus improving frequency offset estimation performance in the DTMB system.
本文的主要工作在于研究和实现DTMB接收端系统的同步部分。本文首先简要介绍和比较了三大标准各自的优缺点,然后详细描述了DTMB系统的关键技术,包括星座映射、帧结构、TDS-OFDM系统等,重点分析了动态多径信道的特征,同步误差的产生原因以及对系统的影响。本文总结了国内外数字电视地面广播传输系统现有的定时恢复和频偏估计算法,提出存在的问题,发现在动态多径信道下算法研究的空间大,对于多径的处理也是一直以来研究的难点。
本文研究一种基于PN帧同步,采用延迟锁相环(DLL)和滑动相关技术的定时恢复的方案,并且为了提高在动态多径信道下定时误差估计的准确性,采用选取多径进行合成运算的方法,重点研究了多径信道下寄生峰、包络内假径和工作不稳定的问题以及解决办法,算法优化后仿真分析表明高Doppler的Rayleigh信道条件下,定时误差可以控制在+／-20ppm范围内。
在动态多径信道条件下频偏波动较大,难以进一步提高估计精度和扩大估计范围,本文综合考虑算法实现的复杂度,提出一种应用于国标数字电视DTMB系统频偏估计的算法改进。通过总结DTMB标准中相位旋转的初始相位的规律,修改相关计算的延迟长度和参与计算的数据长度,提高估计精度,达到频偏估计的多径合成效果。经仿真结果验证,该算法提高了动态多径信道下载波恢复模块工作的稳定性,延长了系统锁定时间,令具有高Doppler的多径信道的剩余频偏绕中心波动在正负10Hz以内,从而改善了DTMB系统频偏估计的性能。
The development of digital television represents the degree of a country's level of digital. The conversion of analogue TV to digital TV in China is expected to be completed by 2015. The development of terrestrial digital television is particularly important. Currently, there are three terrestrial digital TV transmission standards in the world. They are the U.S. ATSC, the European DVB-T and the Japan's ISDB. In August 2006, China formulated a standard named as DTMB(Digital TV terrestrial multimedia broadcasting),this brings about a certain challenges to the realization of terrestrial digital television's modulation and de-modulation. The implementation of national standard and the optimization of digital TV receiver performance directly affect the development of digital television, so the algorithm design of Digital TV receiver IP-chip is the key. There are three modules influenced the receiver performance. They are decoding, equalization and synchronization.
The main work of this thesis is to study and realize the synchronization of DTMB digital TV receiver. In this thesis, first we introduce and compare those three standards briefly, and we describe the main technology of DTMB system, including constellation mapping, framing structure, TDS-OFDM system and so on. We focus on analyzing the characteristics of the dynamic multipath channel, synchronization error causes and influences, and also sum up the domestic and international existing timing recovery and frequency offset estimation algorithm of digital television terrestrial broadcasting transmission system, discuss the problems in algorithm. We find that the research space in the dynamic multipath channel is huge. And the multi-path processing is also a research challenge.
In the thesis, we do some research on a timing recovery algorithm methodology based on PN-sequence frame synchronization, delay-locked Loop and sliding correlation technology. And in order to improve the accuracy of the timing error estimation in the dynamic multi-path channel, we synthesize different echoes correlation results; focus on the research of parasitic peak, pseudo echoes in the envelope and the instability. Computer simulation illustrates timing error can be controlled within the scope of+/-20ppm in the Rayleigh channel with high Doppler frequency.
For the low performance of frequency offset estimation module in the dynamic multi-path channel and the difficulty of improving the estimation accuracy and broadening the scope of frequency offset estimation, we proposed an algorithm of frequency offset estimation in DTMB System. The main research work is the discovery of the rules of preliminary phase of frame head in phase shift mode, and utilizing the rules to optimize the fluctuation of frequency offset in dynamic multi-path channel. We changed the delay length and data length in correlation. Computer simulation illustrates the superior performance of the proposed algorithm in the estimation accuracy and the stability of remaining frequency offset. The remaining frequency offset fluctuates within+/-10Hz in high-Doppler multi-path channel, thus improving frequency offset estimation performance in the DTMB system.
引文
[1]杨知行,杨林.时域同步正交频分复用接收机的定时恢复方法及系统：中国,CN1677910A[P].2005-10-5.
[2]Yang Zhixing, Wang Jun, Han Meng, et al. A combined code acquisition and symbol timing Fecoyery method for TDS OFDM [J]. IEEE Trans. Broadcasting,2003,49(3):304-308.
[3]Liu Guanghui. Comments on"A combined code acquisition and symbol timing recovery method for TDS-OFDM"[J]. IEEE Trans. Broadcasting,2006,52(4):585.
[4]雷俊,吴乐南.改进的OFDM符号粗同步算法[J].应用科学学报,2006,24(3)：237-239.
[5]张洁,蔡鹏,张平.一种适用于多径衰落信道的OFDM定时同步算法[J].北京邮电大学学报,2035,28(2)：106-108.
[6]Donghooll Lee, Kyungwh-Chetm. Coarse Symbol Synchronization Algorithms for OFDM Systems in Multipath Channels[Jil. IEEE. COMMUNICATIONS LE3qERS,2002,6(10、): 446-448.
[7]丰婧,张海滨,钱良.复杂多径环境下的OFDM定时同步改进算法.信息技术,2008,4：4-6
[8]Zheng Z W, Yang Z X, Pan C Y, et al. Novel synchronization for TDS-OFDM based digital television terestrial broadcast systems[J]. IEEE Transcommunication.,2004,50(2):148-153.
[9]Zheng Z W. Robust timing recovery for TDS-OFDM based digital television terrestrial broadcast systems. IEEE Trans Consumer Electronics.2006.52(3):750-756
[10]邹辉,葛建华,等.一种TDS-OFDM系统的载波恢复算法.电视技术,2007(10)：10-12
[11]He Zhongqiu; Han Yang; Fu Xia, "Frequency Synchronization Algorithm Based on PN Sequence", Wireless Communications, Networking and Mobile Computing,2008. WiCOM'08. 4th International Conference on 12-14 Oct.2008 Page(s):1-4
[12]Ling-Long Dai,; Jian Fu,; Wang, Jun; Yang, Zhi-Xing; Alaniz, Arthur, "A new frequency synchronization algorithm in the TDS-OFDM systems",Communication Systems,2008. ICCS 2008.11th IEEE Singapore International Conference on 19-21 Nov.2008 Page(s):44-48
[13]Hyonkyu Lee; Ginkyu Choi; Changwoo Lee, "A new time synchronization algorithm for multi-carrier CDMA signals", Signal Processing Advances in Wireless Communications,1999. SPAWC'99.1999 2nd IEEE Workshop on
[14]Jooyeol Yang; Kyungwhoon Cheun; Jeongchang Kim, "Symbol Timing Synchronization Algorithm for Wireless LAN Systems in Multipath Channels", Communications,2006. APCC'06. Asia-Pacific Conference on,Aug.2006 Page(s):1-5
[15]Liang Wang; Xiuming Shan; Yong Ren, "A new synchronization algorithm for OFDM systems in multipath environment", Communication Systems,2002. ICCS 2002. The 8th International Conference on Volume 1,25-28 Nov.2002 Page(s):255-259 vol.1
[16]Jingfeng Liu; Hongwei Song; Kumar, B.V.K.V., "Symbol timing recovery for low-SNR partial response recording channels", Global Telecommunications Conference,2002. GLOBECOM'02. IEEE Volume 2,17-21 Nov.2002 Page(s):1129-1136 vol.2
[17]Yongxue Zhang; Haidong Fei; Lixin Yu; Yangzhen Xu, "Practical implementation of blind equalization, carrier recovery and timing recovery for QAM cable receiver chip", ASIC,2003. Proceedings.5th International Conference on Volume 2,21-24 Oct.2003 Page(s):886-889 Vol.2
[18]Shi, K.; Serpedin, E., "Fast timing recovery for linearly and nonlinearly modulated systems", Signals, Systems and Computers,2004. Conference Record of the Thirty-Eighth Asilomar Conference on Volume 1,7-10 Nov.2004 Page(s):1015-1019 Vol.1
[19]R. Citta, "Frequency and phase lock loop", IEEE Trans. On Consumer Electronics, vol. CE23, No.3, pp:358-365, Aug.1977
[20]Yang, H.-K.; Snelgrove, M.; "Symbol timing recovery using oversampling techniques", Communications,1996. ICC 96, Conference Record, Converging Technologies for Tomorrow's Applications.1996 IEEE International Conference on Volume 3,23-27 June 1996 Page(s):1296-1300 vol.3
[21]Nayak, A.R.; Barry, J.R.; Feyh, G; McLaughlin, S.W., "Timing Recovery With Frequency Offset and Random Walk:Cramer-Rao Bound and a Phase-Locked Loop Postprocessor", Communications, IEEE Transactions on Volume 54, Issue 11, Nov.2006 Page(s):2004-2013
[22]Shahriar Mirabbasi, Saeed Gazor, and Ken Martin, "A Wideband Carrier-Recovery System for Mutilevel QAM Signals", IEEE international Symposium on Circuits and Systems, May 28-31,2000
[23]Cupo R.L. and Gitlin R.D., "Adaptive Carrier Recovery Systems for Digital Data Communications Receivers", IEEE journal of Selected Areas in Communications, vol,7,No.9, Dec 1999, pp1328-1339
[24]A Touzni et al., "Phase recovery based on minimization of Single-Axis Constant Modulus criterion:Performance analysis", CISS'2001, vol.2, pp:811-816, Mar.2001
[25]Yong-Jung Kim; Dong-Seong Han; Ki-Bum Kim, "A new fast symbol timing recovery algorithm for OFDM systems", Consumer Electronics, IEEE Transactions on Volume 44, Issue 3, Aug.1998 Page(s):1134-1141
[26]Yang Zhang; Yun Chen; Jianming Wu; Xiaoyang Zeng; Dian Zhou,"Optimization of symbol timing recovery for DTMB receivers," ASIC,2007. ASICON'07.7th International Conference on 22-25 Oct.2007 Page(s):822-825
[27]F. Gini and G B. Giannakis, "Frequency offset and symbol timing recovery in flat-fading channels:A cyclostationary approach," IEEE Trans. Commun., vol.46, pp.400-411, Mar.1998.
[28]N. Jablon, "Joint blind equalization, carrier recovery, and timing recovery for high-order QAM signal constellations," IEEE Trans. Signal Processing, vol.40, pp.1383-1397, June 1992.
[29]U. Mengali and A. N. D'Andrea, "Synchronization Techniques for Digital Receivers", New York:Plenum,1997.
[30]Jianming Wu; Yun Chen; Xiaoyang Zeng; Hao Min, "Robust Timing and Frequency Synchronization Scheme for DTMB System", Consumer Electronics, IEEE Transactions on Volume 53, Issue 4, Nov.2007 Page(s):1348-1352
[31]N. Caouras and R. Morawski. "Fast carrier recovery for burst-mode coherent demodulation using feedforward phase and frequency estimation techniques," Proceedings of the IEEE Conference on Electrical and Computer Engineering, May 1999.
[32]Joshua L. Koslov, East Winder, N.J., "Carrier Recovery Using Acquisition and Tracking Modes and Automatic Carrier-to-Noise Estimation",U.S. Patent No:547508 Nov.28,1995
[33]Shuai Zhang,; Xiao-Lin Zhang,; Chao Zhang, "A cyclostationary frequency offset estimation for DTMB system", Signal Processing,2008. ICSP 2008.9th International Conference on 26-29 Oct.2008 Page(s):1822-1825
[34]Hao Zhou; Malipatil, A. Yih-Fang Huang; "OFDM Carrier Synchronization Based on Time-Domain Channel Estimates", Wireless Communications, IEEE Transactions on Volume 7, Issue 8, August 2008 Page(s):2988-2999
[35]Fechtel, S.A., "OFDM carrier and sampling frequency synchronization and its performance on stationary and mobile channels", Consumer Electronics, IEEE Transactions on Volume 46, Issue 3, Aug.2000 Page(s):438-441
[36]梁睿,郭更生.基于定时同步与频偏估计联合检测算法的OFDM系统内接收机的实现与优化.中国学术期刊(光盘版)电子杂志社,CNKI:CDMD:2.2008.139474
[37]武卓峰,赵安安,管云峰,何大治.数字电视地面传输国家标准接收机实现指南.视频技术,2006(11)：41-43
[38]聂韡,李兵兵.基于全数字接收技术的QAM信号定时恢复算法的实现.计算机与信息技术,Computer & Information Technology,编辑部邮箱2007年09期
[39]周晟,陈惠民,金彦亮.一种用于OFDM系统的高性能频偏估计方法.上海大学学报(自然科学版),编辑部邮箱2008.03期
[40]张超,张晓林,张帅.地面数字电视系统中载波同步方法.北京航空航天大学学报,2008年34卷9期：1024-1027
[41]王宁,徐金标,王一丁.中国数字电视OFDM的时频同步及其仿真.通信技术,2007(11)：27-29
[42]聂远飞,王勇,葛建华.多径信道下的OFDM系统定时同步.吉林大学学报：信息科学版,2005年23卷1期：10-15
[2]Yang Zhixing, Wang Jun, Han Meng, et al. A combined code acquisition and symbol timing Fecoyery method for TDS OFDM [J]. IEEE Trans. Broadcasting,2003,49(3):304-308.
[3]Liu Guanghui. Comments on"A combined code acquisition and symbol timing recovery method for TDS-OFDM"[J]. IEEE Trans. Broadcasting,2006,52(4):585.
[4]雷俊,吴乐南.改进的OFDM符号粗同步算法[J].应用科学学报,2006,24(3)：237-239.
[5]张洁,蔡鹏,张平.一种适用于多径衰落信道的OFDM定时同步算法[J].北京邮电大学学报,2035,28(2)：106-108.
[6]Donghooll Lee, Kyungwh-Chetm. Coarse Symbol Synchronization Algorithms for OFDM Systems in Multipath Channels[Jil. IEEE. COMMUNICATIONS LE3qERS,2002,6(10、): 446-448.
[7]丰婧,张海滨,钱良.复杂多径环境下的OFDM定时同步改进算法.信息技术,2008,4：4-6
[8]Zheng Z W, Yang Z X, Pan C Y, et al. Novel synchronization for TDS-OFDM based digital television terestrial broadcast systems[J]. IEEE Transcommunication.,2004,50(2):148-153.
[9]Zheng Z W. Robust timing recovery for TDS-OFDM based digital television terrestrial broadcast systems. IEEE Trans Consumer Electronics.2006.52(3):750-756
[10]邹辉,葛建华,等.一种TDS-OFDM系统的载波恢复算法.电视技术,2007(10)：10-12
[11]He Zhongqiu; Han Yang; Fu Xia, "Frequency Synchronization Algorithm Based on PN Sequence", Wireless Communications, Networking and Mobile Computing,2008. WiCOM'08. 4th International Conference on 12-14 Oct.2008 Page(s):1-4
[12]Ling-Long Dai,; Jian Fu,; Wang, Jun; Yang, Zhi-Xing; Alaniz, Arthur, "A new frequency synchronization algorithm in the TDS-OFDM systems",Communication Systems,2008. ICCS 2008.11th IEEE Singapore International Conference on 19-21 Nov.2008 Page(s):44-48
[13]Hyonkyu Lee; Ginkyu Choi; Changwoo Lee, "A new time synchronization algorithm for multi-carrier CDMA signals", Signal Processing Advances in Wireless Communications,1999. SPAWC'99.1999 2nd IEEE Workshop on
[14]Jooyeol Yang; Kyungwhoon Cheun; Jeongchang Kim, "Symbol Timing Synchronization Algorithm for Wireless LAN Systems in Multipath Channels", Communications,2006. APCC'06. Asia-Pacific Conference on,Aug.2006 Page(s):1-5
[15]Liang Wang; Xiuming Shan; Yong Ren, "A new synchronization algorithm for OFDM systems in multipath environment", Communication Systems,2002. ICCS 2002. The 8th International Conference on Volume 1,25-28 Nov.2002 Page(s):255-259 vol.1
[16]Jingfeng Liu; Hongwei Song; Kumar, B.V.K.V., "Symbol timing recovery for low-SNR partial response recording channels", Global Telecommunications Conference,2002. GLOBECOM'02. IEEE Volume 2,17-21 Nov.2002 Page(s):1129-1136 vol.2
[17]Yongxue Zhang; Haidong Fei; Lixin Yu; Yangzhen Xu, "Practical implementation of blind equalization, carrier recovery and timing recovery for QAM cable receiver chip", ASIC,2003. Proceedings.5th International Conference on Volume 2,21-24 Oct.2003 Page(s):886-889 Vol.2
[18]Shi, K.; Serpedin, E., "Fast timing recovery for linearly and nonlinearly modulated systems", Signals, Systems and Computers,2004. Conference Record of the Thirty-Eighth Asilomar Conference on Volume 1,7-10 Nov.2004 Page(s):1015-1019 Vol.1
[19]R. Citta, "Frequency and phase lock loop", IEEE Trans. On Consumer Electronics, vol. CE23, No.3, pp:358-365, Aug.1977
[20]Yang, H.-K.; Snelgrove, M.; "Symbol timing recovery using oversampling techniques", Communications,1996. ICC 96, Conference Record, Converging Technologies for Tomorrow's Applications.1996 IEEE International Conference on Volume 3,23-27 June 1996 Page(s):1296-1300 vol.3
[21]Nayak, A.R.; Barry, J.R.; Feyh, G; McLaughlin, S.W., "Timing Recovery With Frequency Offset and Random Walk:Cramer-Rao Bound and a Phase-Locked Loop Postprocessor", Communications, IEEE Transactions on Volume 54, Issue 11, Nov.2006 Page(s):2004-2013
[22]Shahriar Mirabbasi, Saeed Gazor, and Ken Martin, "A Wideband Carrier-Recovery System for Mutilevel QAM Signals", IEEE international Symposium on Circuits and Systems, May 28-31,2000
[23]Cupo R.L. and Gitlin R.D., "Adaptive Carrier Recovery Systems for Digital Data Communications Receivers", IEEE journal of Selected Areas in Communications, vol,7,No.9, Dec 1999, pp1328-1339
[24]A Touzni et al., "Phase recovery based on minimization of Single-Axis Constant Modulus criterion:Performance analysis", CISS'2001, vol.2, pp:811-816, Mar.2001
[25]Yong-Jung Kim; Dong-Seong Han; Ki-Bum Kim, "A new fast symbol timing recovery algorithm for OFDM systems", Consumer Electronics, IEEE Transactions on Volume 44, Issue 3, Aug.1998 Page(s):1134-1141
[26]Yang Zhang; Yun Chen; Jianming Wu; Xiaoyang Zeng; Dian Zhou,"Optimization of symbol timing recovery for DTMB receivers," ASIC,2007. ASICON'07.7th International Conference on 22-25 Oct.2007 Page(s):822-825
[27]F. Gini and G B. Giannakis, "Frequency offset and symbol timing recovery in flat-fading channels:A cyclostationary approach," IEEE Trans. Commun., vol.46, pp.400-411, Mar.1998.
[28]N. Jablon, "Joint blind equalization, carrier recovery, and timing recovery for high-order QAM signal constellations," IEEE Trans. Signal Processing, vol.40, pp.1383-1397, June 1992.
[29]U. Mengali and A. N. D'Andrea, "Synchronization Techniques for Digital Receivers", New York:Plenum,1997.
[30]Jianming Wu; Yun Chen; Xiaoyang Zeng; Hao Min, "Robust Timing and Frequency Synchronization Scheme for DTMB System", Consumer Electronics, IEEE Transactions on Volume 53, Issue 4, Nov.2007 Page(s):1348-1352
[31]N. Caouras and R. Morawski. "Fast carrier recovery for burst-mode coherent demodulation using feedforward phase and frequency estimation techniques," Proceedings of the IEEE Conference on Electrical and Computer Engineering, May 1999.
[32]Joshua L. Koslov, East Winder, N.J., "Carrier Recovery Using Acquisition and Tracking Modes and Automatic Carrier-to-Noise Estimation",U.S. Patent No:547508 Nov.28,1995
[33]Shuai Zhang,; Xiao-Lin Zhang,; Chao Zhang, "A cyclostationary frequency offset estimation for DTMB system", Signal Processing,2008. ICSP 2008.9th International Conference on 26-29 Oct.2008 Page(s):1822-1825
[34]Hao Zhou; Malipatil, A. Yih-Fang Huang; "OFDM Carrier Synchronization Based on Time-Domain Channel Estimates", Wireless Communications, IEEE Transactions on Volume 7, Issue 8, August 2008 Page(s):2988-2999
[35]Fechtel, S.A., "OFDM carrier and sampling frequency synchronization and its performance on stationary and mobile channels", Consumer Electronics, IEEE Transactions on Volume 46, Issue 3, Aug.2000 Page(s):438-441
[36]梁睿,郭更生.基于定时同步与频偏估计联合检测算法的OFDM系统内接收机的实现与优化.中国学术期刊(光盘版)电子杂志社,CNKI:CDMD:2.2008.139474
[37]武卓峰,赵安安,管云峰,何大治.数字电视地面传输国家标准接收机实现指南.视频技术,2006(11)：41-43
[38]聂韡,李兵兵.基于全数字接收技术的QAM信号定时恢复算法的实现.计算机与信息技术,Computer & Information Technology,编辑部邮箱2007年09期
[39]周晟,陈惠民,金彦亮.一种用于OFDM系统的高性能频偏估计方法.上海大学学报(自然科学版),编辑部邮箱2008.03期
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