基于FPGA的直扩调制解调器的设计与实现
摘要
扩频通信系统与常规的通信系统相比,具有很强的抗窄带干扰,抗多径干扰,抗人为干扰的能力,并具有信息隐蔽、多址保密通信等优点。在近年来得到了迅速的发展。本论文主要讨论和实现了基于FPGA的直接序列扩频信号的解扩解调处理。论文对该直扩通信系统和FPGA设计方法进行了相关研究,最后用Altera公司的最新的FPGA开发平台Quarus II5.0实现了相关设计。
整个系统分为两个部分,发送部分和接收部分。发送部分主要有串并转换、差分卷积编码、PN码扩频、QPSK调制、成型滤波等模块。接收部分主要有前端抗干扰、数字下变频、解扩解调等模块。
论文首先介绍了扩频通信系统的特点以及相关技术的国内外发展现状,并介绍了本论文的研究思路和内容。
然后,论文分析了几种常用的窄带干扰抑制、载波同步及PN码同步算法,结合实际需要,设计了一种零中频DSSS解调解扩方案。给出了抗窄带干扰、PN码捕获及跟踪以及载波同步的算法分析,采用了基于数字外差调制的自适应陷波器来进行前端窄带干扰抑制处理,用基于自适应门限技术的滑动相关捕获和分时复用单相关器跟踪来改善PN码同步的性能,用基于硬判决的COSTAS(科斯塔斯)环来减少载波提取的算法复杂度,用改进型CORDIC算法实现NCO来方便的进行扩展。
接着,论文给出了系统总体设计和发送及接受子系统的各个功能模块的实现分析以及在Quartus II5.0上的实现细节,给出了仿真结果。
然后论文介绍了整个系统的硬件电路设计和它在真实系统中连机调试所得到的测试结果,结果表明该系统具有性能稳定,灵活性好,生产调试容易,体积小,便于升级等特点并且达到课题各项指标的要求。
最后是对论文工作的一些总结和对今后工作的展望。
The spreading spectrum(SS) communication system has stronger ability of resisting narrow band, multipath and jamming interference than that of the conservation communication systems,and it also has the characteristics of low probability of intercept and multiple access secure communication. Nowadays, the SS technology has gotten rapid progress. This thesis primarily discusses the baseband processing of DSSS communication signal based field programmable gate array (FPGA) ASIC chip. The design technique of FPGA related to SS communication system also has been discussed in this thesis. Finally, the related subsystem has been designed and implemented based on the FPGA development platform Quartus II5.0 belonging to the Altera Company.
The total system can be divided into two parts, i.e., transmitter and receiver unit. The transmitter unit mainly consists of the serial-to-parallel conversion, differential encoder, PN code generator and QPSK modulator and so on. The receiver unit mainly consists of the digital down converter, spread spectrum demodulator, differential demodulator and so on.
Firstly, the thesis introduces the characteristics of the SS communication system and the development related to SS technology at present in the world. The outline and the research idea of the thesis also have been introduced.
Secondly, some algorithms of narrowband interference resisting, PN code and carrier synchronization are presented in this paper. Through practical demand, an algorithm of a digital receiver of DSSS with zero-intermediate frequency is put forward. Narrowband interference resisting algorithm, PN code acquisition and tracking algorithm, carrier demodulation algorithm are described. It resists the narrowband interference by using the digital adaptive heterodyne filter at the forint end. It improves function of PN code synchronization by double threshold series acquisition and time division multiple single correlator tracking. It reduces the complexity of carrier withdrawing algorithm by using soft costas PLL based on sign function. The structure can be easily expanded by using the improved CORDIC algorithm in the implementation of the NCO.
And then, the analysis and the implement detail for all modules based on Quarus II5.0, both transmitter and receiver unit, have been given in this section. The results of behavior simulation of all modules also have been represented.
The hardware design of the whole system and the test results in the system are presented in the paper. It is seen that the system has stable performance, high activity, small size, and can be easily produced and flexibly updated. It is also fit the demand of the system.
The summaries of the thesis and the possible extensions and improvements based on the completed system have been represented at last.
整个系统分为两个部分,发送部分和接收部分。发送部分主要有串并转换、差分卷积编码、PN码扩频、QPSK调制、成型滤波等模块。接收部分主要有前端抗干扰、数字下变频、解扩解调等模块。
论文首先介绍了扩频通信系统的特点以及相关技术的国内外发展现状,并介绍了本论文的研究思路和内容。
然后,论文分析了几种常用的窄带干扰抑制、载波同步及PN码同步算法,结合实际需要,设计了一种零中频DSSS解调解扩方案。给出了抗窄带干扰、PN码捕获及跟踪以及载波同步的算法分析,采用了基于数字外差调制的自适应陷波器来进行前端窄带干扰抑制处理,用基于自适应门限技术的滑动相关捕获和分时复用单相关器跟踪来改善PN码同步的性能,用基于硬判决的COSTAS(科斯塔斯)环来减少载波提取的算法复杂度,用改进型CORDIC算法实现NCO来方便的进行扩展。
接着,论文给出了系统总体设计和发送及接受子系统的各个功能模块的实现分析以及在Quartus II5.0上的实现细节,给出了仿真结果。
然后论文介绍了整个系统的硬件电路设计和它在真实系统中连机调试所得到的测试结果,结果表明该系统具有性能稳定,灵活性好,生产调试容易,体积小,便于升级等特点并且达到课题各项指标的要求。
最后是对论文工作的一些总结和对今后工作的展望。
The spreading spectrum(SS) communication system has stronger ability of resisting narrow band, multipath and jamming interference than that of the conservation communication systems,and it also has the characteristics of low probability of intercept and multiple access secure communication. Nowadays, the SS technology has gotten rapid progress. This thesis primarily discusses the baseband processing of DSSS communication signal based field programmable gate array (FPGA) ASIC chip. The design technique of FPGA related to SS communication system also has been discussed in this thesis. Finally, the related subsystem has been designed and implemented based on the FPGA development platform Quartus II5.0 belonging to the Altera Company.
The total system can be divided into two parts, i.e., transmitter and receiver unit. The transmitter unit mainly consists of the serial-to-parallel conversion, differential encoder, PN code generator and QPSK modulator and so on. The receiver unit mainly consists of the digital down converter, spread spectrum demodulator, differential demodulator and so on.
Firstly, the thesis introduces the characteristics of the SS communication system and the development related to SS technology at present in the world. The outline and the research idea of the thesis also have been introduced.
Secondly, some algorithms of narrowband interference resisting, PN code and carrier synchronization are presented in this paper. Through practical demand, an algorithm of a digital receiver of DSSS with zero-intermediate frequency is put forward. Narrowband interference resisting algorithm, PN code acquisition and tracking algorithm, carrier demodulation algorithm are described. It resists the narrowband interference by using the digital adaptive heterodyne filter at the forint end. It improves function of PN code synchronization by double threshold series acquisition and time division multiple single correlator tracking. It reduces the complexity of carrier withdrawing algorithm by using soft costas PLL based on sign function. The structure can be easily expanded by using the improved CORDIC algorithm in the implementation of the NCO.
And then, the analysis and the implement detail for all modules based on Quarus II5.0, both transmitter and receiver unit, have been given in this section. The results of behavior simulation of all modules also have been represented.
The hardware design of the whole system and the test results in the system are presented in the paper. It is seen that the system has stable performance, high activity, small size, and can be easily produced and flexibly updated. It is also fit the demand of the system.
The summaries of the thesis and the possible extensions and improvements based on the completed system have been represented at last.
引文
[1] 沈允春. “扩谱技术”. 国防工业出版社. 1995 年 7 月.
[2] 查光明,熊贤祚. “扩频通信”. 第 1 版.西安电子科技大学出版社.1990 年 12 月.
[3] 郭梯云,杨家玮,李建东.数字移动通信.人民邮电出版社.1995
[4] Wu Limin, Xue Feng. ”Aplication of Software Radio Architecture To the Spread Spectrum Communication System”. TENCON '02. Proceedings. 2002 IEEE Region 10 Conference on Computers .
[5] Cai Tao,Song junde, Wang hai. “ A new architecture of third generation mobile system based on software radio”. Communication Technology Proceedings, 1998.
[6] Julio E.Castro,James P.LeBlanc. “Multidimensional extension of mmse linear adaptive receiver for dsss systems”.IEEE Fifth International Symposium on Signal Processing and its Applicatins.August 1999.pp22-25
[7] Xiaowen Chen,Wei Guo,Yong Zheng. “Frequency Domain Interference Suppression in a Dsss system”. IEEE 2002. pp247-251.
[8] 薛巍,向敬成,黄怀信. “基于门限估计的直扩通信系统窄带干扰变换域抑制方法”.电子与信息学报.2003年7月.Vol.25.No.7.pp990-994.
[9] G.J.Saulnier. “Suppression of narrowband jammers in a spread-spectrum receiver using transform-domain adaptive filtering”. IEEE Journal on Selected Areas in Communications. May,1992. Vol.10(4). pp742-749
[10] A.Bultan,A.N.Akansu. “A novel time-frequency exciser in spread spectrum communications for chirp-like interference”.IEEE 1998.pp3265-3268.
[11] 辜伯安,何四新,“DS扩频信号数字解扩的工程实现途径”,电讯技术,Vol-36 (1)1996.
[12] Bong-Young Chung,Charles Chien,Henry Samueli,Rajeev Jain. “Performance Analysis of an All-Digital BPSK Direct Sequence Spread-Spectrum IF Receiver Architecture”.IEEE Journal on selected areas in communications.vol.11,(7),sept 1993
[13] F.L.A.J.Kamperman.“Design of an all digital direct-sequence spread-spectrum receiver”, IEEE International Symposium on , Volume: 4 , 18-23 Sept. 1994
[14] Stephan Berner ,Phillip De Leon. “Parallel digital architectures for high-speed adaptive DSSS receivers”. Conference Record of the Thirty-Fourth Asilomar Conference on , Volume: 2 , 29 Oct.-1 Nov. 2000
[15] 黄振,杨士中.“匹配滤波器解扩方式及性能”.重庆大学学报.2002年1月.Vol25(1).
[16] Gianluca Mazzini, Riccardo Rovatti, Gianluca Setti. “Sequence synchronization in chaos-based DS-CDMA systems”. Proceedings of the 1998 IEEE International Symposium on Volume 4, 31 May-3 June 1998 Page(s):485 - 488 vol.4
[17] 李署坚,任俊涛,王丹志,邵定蓉.“基于DSP的高动态数字解扩接收机的研究”.航空学报.vol-22,June.2001
[18] S.Lee, J.Kim.”Effects of multiple threshold values for PN code acquisition in DS-CDMA systems”. Electronics Letters Volume 37, Issue 6, 15 Mar 2001 Page(s):363 - 365
[19] Mehrnia, A, Shakeri, K, Eftekhar, A.A, Soheili, F, Nassiri, m, Fotowat, A. “An all digital spread spectrum processor featuring multiplier free zero-IF down-conversion, decimation and multiplexed dispreading”. Microelectronics, 2000. ICM 2000. Proceedings of the 12th International Conference on , 31 Oct.-2 Nov. 2000
[20] 王永林,王丽娜.“DS-SS系统解扩技术研究”.无线电通信技术.Vol-25(1)1999.
[21] Yugang Ma,K.H.Li,Alex C.Kot.”A novel transform domain fully digital PN code tracking loop”. Vehicular Technology Conference Proceedings, 2000. VTC 2000-Spring Tokyo. 2000 IEEE 51stVolume 2, 15-18 May 2000 Page(s):1286 - 1289 vol.2
[22] Oliver Leung,Chi-ying Tsui,Roger S.Cheng.”VLSI Implementation of Rake Receiver for IS-95 CDMA Testbed using FPGA”.Design Automation Conference, 2000. Proceedings of the ASP-DAC 2000. Asia and South Pacific , 25-28 Jan. 2000
[23] Xiaofu Wu,Cong Ling,Haige Xiang.”Despreading chip waveform design for coherent delay-locked tracking in DS/SS systems”. Communications, 2002. ICC 2002. IEEE International Conference on Volume 1, 28 April-2 May 2002 Page(s):631 – 635
[24] Hung Nguyen. “Improving QPSK demodulator performance for quadrature receiver with information from amplitude and phase imbalance correction“. Wireless Communications and Networking Conference, 2000.
[25] 刘会杰,张乃通 .“QPSK 信号相干载波提取的仿真研究 ”. 系统工程与电子技术.Vol-25(4),2003
[26] 苏仁宏,杨士中.“移动通信中的 π / 4QPSK调制解调技术及DSP实现”.电讯技术.Vol-38(4),1998.
[27] 强刚,刘乃安,刘增基.“高速突发通信零中频接收技术研究”.西安电子科技大学学报.2002年4月.Vol-29(2).
[28] Paul T.Capozza. “A Single-Chip Narrow Band Frequency Domain Excisor for a Global Positioning System (GPS)Receiver”. IEEE Journal of Solid-State Circuits. MARCH 2000. VOL. 35(3). pp401-411
[29] Julio E.Castro,James P.LeBlanc. “Multidimensional extension of mmse linear adaptivereceiver for dsss systems”.IEEE Fifth International Symposium on Signal Processing and its Applicatins.August 1999.pp22-25
[30] E.Masry. “Closed-Form Analytical Results for the Rejection of Narrow-Band Interference in PN Spread-Spectrum Systems--Part II: Linear Interpolation Filters”. IEEE Transactions on Communications. Jan 1985. Vol.33(1). pp10-19
[31] Rajiv Vijayan,H.Vincent Poor. “Nonlinear techniques for interference suppression in spread-spectrum systems”. IEEE Transactions on Communications. July 1990. Vol.38(7). pp1060-1065
[32] Julio E.Castro,James P.LeBlanc. “Multidimensional extension of mmse linear adaptive receiver for dsss systems”.IEEE Fifth International Symposium on Signal Processing and its Applicatins.August 1999.pp22-25
[32] M.Sangriotis,I.Xezonakis.”Digital costas loop-like Pll for the carrier recovery of a QPSK signal”. Communications, 2002. ICC 2002. IEEE International Conference on Volume 1, 28 April-2 May 2002 Page(s):631 – 635
[33] Xiaowen Chen,Wei Guo,Yong Zheng. “Frequency Domain Interference Suppression in a Dsss system”.IEEE 2002.pp247-251.
[34] M.A.Soderstrand,K.E.Nelson.“Implementation of complex-arithmetic heterodyne filter”.IEEE August 2003.pp230-235.
[35] A. J. Viterbi. “CDMA: Principles of Spread Spectrum Communication”. Reading, MA: Addison-Wesley, 1995, ch. 2–4.
[36] E. Sourour and S. C. Gupta. “Direct-sequence spread-spectrum parallel acquisition in nonselective and frequency-selective Rician fading channels,”IEEE J. Select. Areas Commun., vol. 10, no. 3, pp. 535–544, 1992.
[37] Tan Xiao-heng; Yang Shi-zhong.” The design and FPGA realization of the long PN code acquisition circuit based on digital matched-filter”; ASIC, 2003. Proceedings. 5th nternational Conference on Volume 2, 21-24 Oct. 2003 Page(s):744 - 747 Vol.2
[38] El-Tarhuni, M.G.; Sheikh, A.U.H .”An adaptive filtering PN code acquisition scheme with improved acquisition based capacity in DS/CDMA” .Personal, Indoor and Mobile Radio Communications, 1998. The Ninth IEEE International Symposium on Volume 3, 8-11 Sept. 1998 Page(s):1486 - 1490 vol.3
[39] Okamoto, H.; Hasegawa, T. ”Delay-lock phase-locked tracking of PN signals (DPTL)”. Singapore ICCS/ISITA '92. 'Communications on the Move' 16-20 Nov. 1992 Page(s):305 - 308 vol.1
[40] 袁清升,刘 文.“相位处理载波恢复算法研究”.信息与电子工程.Vol.1 No 2.Jun 2003
[41] 王 钢,刘毅鹏.“载波同步技术的研究”.通信技术.2003年第1期,总第133期.
[42] Attapol Wannasarnmaytha, Shinsuke Hara, and Norihiko Morinaga.”Two-Step Kalman- Filter-Based AFC for Direct Conversion-Type Receiver in LEO SatelliteCommunications”. IEEE transactions on vehicular technology,Vol.49,NO.1,January 2000.
[43] 杨小牛,楼才义,徐建良著.《软件无线电原理及应用》.电子工业出版社.
[44] 张厥盛,郑继禹,万心平.《锁相技术》.西安电子科技大学出版社.
[45] Uwe Meyer-Baese 著,刘凌,胡永生译.《数字信号处理的FPGA实现》.清华大学出版社.
[2] 查光明,熊贤祚. “扩频通信”. 第 1 版.西安电子科技大学出版社.1990 年 12 月.
[3] 郭梯云,杨家玮,李建东.数字移动通信.人民邮电出版社.1995
[4] Wu Limin, Xue Feng. ”Aplication of Software Radio Architecture To the Spread Spectrum Communication System”. TENCON '02. Proceedings. 2002 IEEE Region 10 Conference on Computers .
[5] Cai Tao,Song junde, Wang hai. “ A new architecture of third generation mobile system based on software radio”. Communication Technology Proceedings, 1998.
[6] Julio E.Castro,James P.LeBlanc. “Multidimensional extension of mmse linear adaptive receiver for dsss systems”.IEEE Fifth International Symposium on Signal Processing and its Applicatins.August 1999.pp22-25
[7] Xiaowen Chen,Wei Guo,Yong Zheng. “Frequency Domain Interference Suppression in a Dsss system”. IEEE 2002. pp247-251.
[8] 薛巍,向敬成,黄怀信. “基于门限估计的直扩通信系统窄带干扰变换域抑制方法”.电子与信息学报.2003年7月.Vol.25.No.7.pp990-994.
[9] G.J.Saulnier. “Suppression of narrowband jammers in a spread-spectrum receiver using transform-domain adaptive filtering”. IEEE Journal on Selected Areas in Communications. May,1992. Vol.10(4). pp742-749
[10] A.Bultan,A.N.Akansu. “A novel time-frequency exciser in spread spectrum communications for chirp-like interference”.IEEE 1998.pp3265-3268.
[11] 辜伯安,何四新,“DS扩频信号数字解扩的工程实现途径”,电讯技术,Vol-36 (1)1996.
[12] Bong-Young Chung,Charles Chien,Henry Samueli,Rajeev Jain. “Performance Analysis of an All-Digital BPSK Direct Sequence Spread-Spectrum IF Receiver Architecture”.IEEE Journal on selected areas in communications.vol.11,(7),sept 1993
[13] F.L.A.J.Kamperman.“Design of an all digital direct-sequence spread-spectrum receiver”, IEEE International Symposium on , Volume: 4 , 18-23 Sept. 1994
[14] Stephan Berner ,Phillip De Leon. “Parallel digital architectures for high-speed adaptive DSSS receivers”. Conference Record of the Thirty-Fourth Asilomar Conference on , Volume: 2 , 29 Oct.-1 Nov. 2000
[15] 黄振,杨士中.“匹配滤波器解扩方式及性能”.重庆大学学报.2002年1月.Vol25(1).
[16] Gianluca Mazzini, Riccardo Rovatti, Gianluca Setti. “Sequence synchronization in chaos-based DS-CDMA systems”. Proceedings of the 1998 IEEE International Symposium on Volume 4, 31 May-3 June 1998 Page(s):485 - 488 vol.4
[17] 李署坚,任俊涛,王丹志,邵定蓉.“基于DSP的高动态数字解扩接收机的研究”.航空学报.vol-22,June.2001
[18] S.Lee, J.Kim.”Effects of multiple threshold values for PN code acquisition in DS-CDMA systems”. Electronics Letters Volume 37, Issue 6, 15 Mar 2001 Page(s):363 - 365
[19] Mehrnia, A, Shakeri, K, Eftekhar, A.A, Soheili, F, Nassiri, m, Fotowat, A. “An all digital spread spectrum processor featuring multiplier free zero-IF down-conversion, decimation and multiplexed dispreading”. Microelectronics, 2000. ICM 2000. Proceedings of the 12th International Conference on , 31 Oct.-2 Nov. 2000
[20] 王永林,王丽娜.“DS-SS系统解扩技术研究”.无线电通信技术.Vol-25(1)1999.
[21] Yugang Ma,K.H.Li,Alex C.Kot.”A novel transform domain fully digital PN code tracking loop”. Vehicular Technology Conference Proceedings, 2000. VTC 2000-Spring Tokyo. 2000 IEEE 51stVolume 2, 15-18 May 2000 Page(s):1286 - 1289 vol.2
[22] Oliver Leung,Chi-ying Tsui,Roger S.Cheng.”VLSI Implementation of Rake Receiver for IS-95 CDMA Testbed using FPGA”.Design Automation Conference, 2000. Proceedings of the ASP-DAC 2000. Asia and South Pacific , 25-28 Jan. 2000
[23] Xiaofu Wu,Cong Ling,Haige Xiang.”Despreading chip waveform design for coherent delay-locked tracking in DS/SS systems”. Communications, 2002. ICC 2002. IEEE International Conference on Volume 1, 28 April-2 May 2002 Page(s):631 – 635
[24] Hung Nguyen. “Improving QPSK demodulator performance for quadrature receiver with information from amplitude and phase imbalance correction“. Wireless Communications and Networking Conference, 2000.
[25] 刘会杰,张乃通 .“QPSK 信号相干载波提取的仿真研究 ”. 系统工程与电子技术.Vol-25(4),2003
[26] 苏仁宏,杨士中.“移动通信中的 π / 4QPSK调制解调技术及DSP实现”.电讯技术.Vol-38(4),1998.
[27] 强刚,刘乃安,刘增基.“高速突发通信零中频接收技术研究”.西安电子科技大学学报.2002年4月.Vol-29(2).
[28] Paul T.Capozza. “A Single-Chip Narrow Band Frequency Domain Excisor for a Global Positioning System (GPS)Receiver”. IEEE Journal of Solid-State Circuits. MARCH 2000. VOL. 35(3). pp401-411
[29] Julio E.Castro,James P.LeBlanc. “Multidimensional extension of mmse linear adaptivereceiver for dsss systems”.IEEE Fifth International Symposium on Signal Processing and its Applicatins.August 1999.pp22-25
[30] E.Masry. “Closed-Form Analytical Results for the Rejection of Narrow-Band Interference in PN Spread-Spectrum Systems--Part II: Linear Interpolation Filters”. IEEE Transactions on Communications. Jan 1985. Vol.33(1). pp10-19
[31] Rajiv Vijayan,H.Vincent Poor. “Nonlinear techniques for interference suppression in spread-spectrum systems”. IEEE Transactions on Communications. July 1990. Vol.38(7). pp1060-1065
[32] Julio E.Castro,James P.LeBlanc. “Multidimensional extension of mmse linear adaptive receiver for dsss systems”.IEEE Fifth International Symposium on Signal Processing and its Applicatins.August 1999.pp22-25
[32] M.Sangriotis,I.Xezonakis.”Digital costas loop-like Pll for the carrier recovery of a QPSK signal”. Communications, 2002. ICC 2002. IEEE International Conference on Volume 1, 28 April-2 May 2002 Page(s):631 – 635
[33] Xiaowen Chen,Wei Guo,Yong Zheng. “Frequency Domain Interference Suppression in a Dsss system”.IEEE 2002.pp247-251.
[34] M.A.Soderstrand,K.E.Nelson.“Implementation of complex-arithmetic heterodyne filter”.IEEE August 2003.pp230-235.
[35] A. J. Viterbi. “CDMA: Principles of Spread Spectrum Communication”. Reading, MA: Addison-Wesley, 1995, ch. 2–4.
[36] E. Sourour and S. C. Gupta. “Direct-sequence spread-spectrum parallel acquisition in nonselective and frequency-selective Rician fading channels,”IEEE J. Select. Areas Commun., vol. 10, no. 3, pp. 535–544, 1992.
[37] Tan Xiao-heng; Yang Shi-zhong.” The design and FPGA realization of the long PN code acquisition circuit based on digital matched-filter”; ASIC, 2003. Proceedings. 5th nternational Conference on Volume 2, 21-24 Oct. 2003 Page(s):744 - 747 Vol.2
[38] El-Tarhuni, M.G.; Sheikh, A.U.H .”An adaptive filtering PN code acquisition scheme with improved acquisition based capacity in DS/CDMA” .Personal, Indoor and Mobile Radio Communications, 1998. The Ninth IEEE International Symposium on Volume 3, 8-11 Sept. 1998 Page(s):1486 - 1490 vol.3
[39] Okamoto, H.; Hasegawa, T. ”Delay-lock phase-locked tracking of PN signals (DPTL)”. Singapore ICCS/ISITA '92. 'Communications on the Move' 16-20 Nov. 1992 Page(s):305 - 308 vol.1
[40] 袁清升,刘 文.“相位处理载波恢复算法研究”.信息与电子工程.Vol.1 No 2.Jun 2003
[41] 王 钢,刘毅鹏.“载波同步技术的研究”.通信技术.2003年第1期,总第133期.
[42] Attapol Wannasarnmaytha, Shinsuke Hara, and Norihiko Morinaga.”Two-Step Kalman- Filter-Based AFC for Direct Conversion-Type Receiver in LEO SatelliteCommunications”. IEEE transactions on vehicular technology,Vol.49,NO.1,January 2000.
[43] 杨小牛,楼才义,徐建良著.《软件无线电原理及应用》.电子工业出版社.
[44] 张厥盛,郑继禹,万心平.《锁相技术》.西安电子科技大学出版社.
[45] Uwe Meyer-Baese 著,刘凌,胡永生译.《数字信号处理的FPGA实现》.清华大学出版社.