OFDM在高频数字通信中的应用
摘要
由于具备潜在的全球覆盖能力、无需第三方设备介入、架设方便等技术优势，高频数据通信在通信技术高度发达的今天仍有广阔的应用前景。正交频分复用(OFDM)技术于上世纪六十年代提出，是一种典型的多载波调制方式。基于DFT的正交频分复用(OFDM)技术的提出，为HF通信频谱利用率与传输速率问题提供了新的解决方案。作者针对OFDM技术在高频数据通信的应用，作了如下工作：
1．分析高频数据通信物理层的OFDM系统设计、基于Watterson高频信道统计模型与OFDM基本原理，在此基础上提出具体的参数选择方法(式4.4)；
2．根据作者提出的参数选择方案，设计了在SSB电台带宽上适合于CCIR典型HF信道的系统方案，其有效传输速率可达到4800bps、7200bps，甚至更高；
3．基于本文的设计方案，讨论了过采样、调制映射方式、信道编码、信道估计等问题，并对相应系统的设计作出了MATLAB／SIMULINK仿真，仿真结果与理论预测相符。
作者的工作表明：OFDM技术抗多径能力强、频谱利用率高、易于实现的优势对高频数据通信有广阔的应用价值，采用作者提出的系统设计方案可把OFDM系统有效地应用于高频信道。
High Frequency (HF) data communication links remain relevant even in today's novel era. By using DFT based OFDM, there is new research direction for more efficienct and high speed HF technology. This thesis examines the design of the physical layer for an OFDM system utilising novel digital signal processing algorithms. A new method for parameter design is offered in detail, implementing the procedure in CCIR HF channel. The effective communication rate reachs 4800, 7200 bps in standard 3 kHz voiceband channel allocation. Based on the parameter designs, a Matlab simulation is presented. The result is consilient with theoretics assumption.
1．分析高频数据通信物理层的OFDM系统设计、基于Watterson高频信道统计模型与OFDM基本原理，在此基础上提出具体的参数选择方法(式4.4)；
2．根据作者提出的参数选择方案，设计了在SSB电台带宽上适合于CCIR典型HF信道的系统方案，其有效传输速率可达到4800bps、7200bps，甚至更高；
3．基于本文的设计方案，讨论了过采样、调制映射方式、信道编码、信道估计等问题，并对相应系统的设计作出了MATLAB／SIMULINK仿真，仿真结果与理论预测相符。
作者的工作表明：OFDM技术抗多径能力强、频谱利用率高、易于实现的优势对高频数据通信有广阔的应用价值，采用作者提出的系统设计方案可把OFDM系统有效地应用于高频信道。
High Frequency (HF) data communication links remain relevant even in today's novel era. By using DFT based OFDM, there is new research direction for more efficienct and high speed HF technology. This thesis examines the design of the physical layer for an OFDM system utilising novel digital signal processing algorithms. A new method for parameter design is offered in detail, implementing the procedure in CCIR HF channel. The effective communication rate reachs 4800, 7200 bps in standard 3 kHz voiceband channel allocation. Based on the parameter designs, a Matlab simulation is presented. The result is consilient with theoretics assumption.
引文
[1] 美军标 MIL-STD-188-141B
[2] 美军标 MIL-STD-188-141B APPENDIX C THIRD-GENERA TION HF LINK AUTOMATION
[3] Martin Christopher Gill, "Coded-Waveform Design for High Speed Data Transfer over HF Radio Channels". Doctor thesis. February 1998
[4] Watterson C.C, Juroshek J.R and Bensema W.D (1970), "Experimental Confirmation of an HF Channel Model", IEE Transactions on Communications Technology, Vol COM-18, No 6, Dec 1970.
[5] CCIR (1986) "HF Ionospheric Channel Simulators", Report 549-2, Recommendations and Reports of the CCIR. Volume Ⅲ. ITU. Geneva. pp.59-67.
[6] CCIR (1980) "Recommendation 520-1 Use of High Frequency Ionospheric Channel Simulators", Recommendations and Reports of the CCIR, Volume Ⅲ, pp.57-58 ITU, Geneva.
[7] John G.Proakis，《数字通信》(第四版)电子工业出版社，2003年1月
[8] 佟学俭、罗涛，《OFDM移动通信技术原理与应用》，人民邮电出版社，2003．6
[9] 王文博、郑侃，《宽带无线通信OFDM技术》，人民邮电出版社，2003．11
[10] 沈琪琪、朱德生，《短波通信》，西安电子科技大学出版社，1989年12月
[11] 陈浩，《短波通信新技术与新体制》，信息产业部电子第七研究所
[12] 张贤达、保铮，《通信信号处理》，国防工业出版社，2000年12月
[13] 郭梯云、杨家玮、李建东，《数字移动通信》，人民邮电出版社，2001．3
[14] 王立宁、乐光新、詹菲，《MATLAB与通信仿真》，人民邮电出版社，1999
[15] 樊昌信、詹道庸、徐炳祥等，《通信原理》第4版，国防工业出版社，1995
[16] 王新梅、肖国镇，《纠错码—原理与方法》(修订版)西安电子科技大学出版社，2001
[17] 戴耀森，《短波自适应选频技术》，浙江科学技术出版社，1992．8
[18] 姚俊、马松辉．《Simulink建模与仿真》，西安电子科技大学出版社，2002年8月
[19] 王强、孙锦涛、谢仁宏，《OFDM在短波数据通信中的应用》，通信技术，2001年第1期，15-17
[20] 徐发强、李锦祥、益晓新，《OFDM系统在短波宽带信道上均衡方法》，解放军理工大学学报(自然科学版)，2002年2月，第3卷第1期
[21] 吕浚哲、张海林、何非、刘增基，《无保护间隔的OFDM信道自适应均衡的一种新算法》，
电子学报，第7期2002年7月
[22] 王强、孙锦涛、叶晓东、谢仁宏，《差分TurbO—OFDM在短波数据通信中的应用研究》，南京理工大学学报(自然科学版)，26(2)，2002，144-147
[23] Zhang L and Giles T.C (1995), "A Comparison of Coded Modulation Schemes on HF Channels", Proceedings 3rd UK-CIS International Symposium on Communications Theory and Applications, Lakes District, UK, July 1995.
[24] Gill M.C, Cook S.C, Giles T.C and Ball J.Y (1995) "A 300 to 3600 bps Multi-Rate HF Parallel Tone Modem", Proceedings IEEE Conference on Military Communications (MILCOM '95), San Diego USA, Vol 3, pp.1066-1070.
[25] Morris S.P and Gill M.C (1997), "Coded Modulation Enhancements to an HF Single-Tone Modem", Conf Proe HF Radio Systems and Techniques'97, Nottingham, UK, July 1997, pp.85-89.
[26] E. Johnson, "E-Mail Standards for HF Radio" Technical Report, NMSU, July 2001.
[27] NATO Standardisation Agreement (STANAG) 4539, Technical Standards For Non-Hopping HF Communications Waveforms.
[28] NATO STANAG 5066, Profile For High Frequency (HF) Radio Data Communications.
[29] Ian Poole, Radio Waves and the Ionosphere, November 1999
[30] Moe Wheatley, PathSim User and Technical Guide Ver. 1.0 Dec, 2000
[31] Mehdi Rostami, Joao Angeja, Joao Tavares and Antonio Navarro, HF Channel Modeling for Real Time Packet Transmission, 2003-04-15
[32] 束锋、吴乐南，《16DAPSK+OFDM及其在数字调幅广播中应用》，电路与系统学报，第6卷第3期，2001年9月
[33] Jan E.M.Nilsson and Timothy C. Giles, Wideband multi-carrier transmission for military HF communication, 1997 IEEE
[34] Timothy C. Giles and Ian Willoughby, Simulation of high frequency voice band radio channels, 1993 IEEE
[35] R.J.Miller&R.C.Lock, OFDM design considerations using the HF fading channel, 1995 IEE
[36] A F Kurpiers, Improved channel estimation and demodulation for OFDM on HF ionospheric channels, 2000 IEE
[37] IEEE Std 802.11a/D7.0-1999, Part11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: High Speed Physical Layer in the 5GHz Band.
[38] IEEE Std 802.16: Air Interface for Fixed Broadband Wireless Access Systems
[39] Angela Doufexi, Simon Armour, Andrew Nix, and Mark Beach, Evaluating the Physical Layer Performance of an OFDM candidate for Fourth Generation Networks, IST SATURN
[40] European Telecommunications Standards Institute, ETS 300 744: Digital Video Broadcasting (DVB-T).
[41] ETSI, "Broadband Radio Access Networks (BRAN): HIPERLAN type 2 technical specification: Physical (PHY) layer," August 1999.
[42] IEEE 802.16.3.p-00/33. "OFDM/OFDMA PHY proposal" Yossi Segal, RunCom Technologies.
[43] John W.Nieto, ITERATIVE EQUALIZATION AND DECODING OF STANAG 4539 9600 BPS HF WAVEFORMS, Harris Corporation, RF Communications Division
[44] Vladimir N. Ivanov. Arthur A. Lanne. Igor V. Moroz, Oleg B. Semienov, Sergey N. Frolov. Implementing Vcoder and HF ModemAlgorithms Using the TMS320C31 DSP, September 1996
[45] S.C.Cook, M.C.Gill. T.C.Giles "A High-Speed HF Parallel-Tone Modem ". "HF Radio Systems,and Techniques", 4-7 July 1994, Conference Publication, No.392, pp. 175-181.
[46] T C Giles, A high-speed modem with built-in HF noise tolerance, July 1994 IEE
[47] TIMOTHY C. GILES. "ON THE DESIGN OF HF RADIO MODEMS", Doctor Thesis, December. 1995
[48] Ungerboeck G (1982), "Channels coding with multi-level phase signals", IEEE Trans. Inform.Theory, IT-28, Jan. 1982, pp.55-67.
[49] T C Giles, HF MODEM DESIGN FOR EXTREMELY HIGH SIMULTANEOUS DOPPLER AND DELAY SPREADS
[50] Jan E.M, Nlisson and T C.Giles, Wideband multi-carrier transmission for military HF communication, 1997 IEEE
[51] T.J. Willink, N.C.Davies, M.J. Angling, V. Jodalen and B. Lundborg, "Robust HF data communications at high latitudes", IEE Proceedings of Microwave, Antennasand Propagation, Vol. 146, No. 4, August 1999.
[2] 美军标 MIL-STD-188-141B APPENDIX C THIRD-GENERA TION HF LINK AUTOMATION
[3] Martin Christopher Gill, "Coded-Waveform Design for High Speed Data Transfer over HF Radio Channels". Doctor thesis. February 1998
[4] Watterson C.C, Juroshek J.R and Bensema W.D (1970), "Experimental Confirmation of an HF Channel Model", IEE Transactions on Communications Technology, Vol COM-18, No 6, Dec 1970.
[5] CCIR (1986) "HF Ionospheric Channel Simulators", Report 549-2, Recommendations and Reports of the CCIR. Volume Ⅲ. ITU. Geneva. pp.59-67.
[6] CCIR (1980) "Recommendation 520-1 Use of High Frequency Ionospheric Channel Simulators", Recommendations and Reports of the CCIR, Volume Ⅲ, pp.57-58 ITU, Geneva.
[7] John G.Proakis，《数字通信》(第四版)电子工业出版社，2003年1月
[8] 佟学俭、罗涛，《OFDM移动通信技术原理与应用》，人民邮电出版社，2003．6
[9] 王文博、郑侃，《宽带无线通信OFDM技术》，人民邮电出版社，2003．11
[10] 沈琪琪、朱德生，《短波通信》，西安电子科技大学出版社，1989年12月
[11] 陈浩，《短波通信新技术与新体制》，信息产业部电子第七研究所
[12] 张贤达、保铮，《通信信号处理》，国防工业出版社，2000年12月
[13] 郭梯云、杨家玮、李建东，《数字移动通信》，人民邮电出版社，2001．3
[14] 王立宁、乐光新、詹菲，《MATLAB与通信仿真》，人民邮电出版社，1999
[15] 樊昌信、詹道庸、徐炳祥等，《通信原理》第4版，国防工业出版社，1995
[16] 王新梅、肖国镇，《纠错码—原理与方法》(修订版)西安电子科技大学出版社，2001
[17] 戴耀森，《短波自适应选频技术》，浙江科学技术出版社，1992．8
[18] 姚俊、马松辉．《Simulink建模与仿真》，西安电子科技大学出版社，2002年8月
[19] 王强、孙锦涛、谢仁宏，《OFDM在短波数据通信中的应用》，通信技术，2001年第1期，15-17
[20] 徐发强、李锦祥、益晓新，《OFDM系统在短波宽带信道上均衡方法》，解放军理工大学学报(自然科学版)，2002年2月，第3卷第1期
[21] 吕浚哲、张海林、何非、刘增基，《无保护间隔的OFDM信道自适应均衡的一种新算法》，
电子学报，第7期2002年7月
[22] 王强、孙锦涛、叶晓东、谢仁宏，《差分TurbO—OFDM在短波数据通信中的应用研究》，南京理工大学学报(自然科学版)，26(2)，2002，144-147
[23] Zhang L and Giles T.C (1995), "A Comparison of Coded Modulation Schemes on HF Channels", Proceedings 3rd UK-CIS International Symposium on Communications Theory and Applications, Lakes District, UK, July 1995.
[24] Gill M.C, Cook S.C, Giles T.C and Ball J.Y (1995) "A 300 to 3600 bps Multi-Rate HF Parallel Tone Modem", Proceedings IEEE Conference on Military Communications (MILCOM '95), San Diego USA, Vol 3, pp.1066-1070.
[25] Morris S.P and Gill M.C (1997), "Coded Modulation Enhancements to an HF Single-Tone Modem", Conf Proe HF Radio Systems and Techniques'97, Nottingham, UK, July 1997, pp.85-89.
[26] E. Johnson, "E-Mail Standards for HF Radio" Technical Report, NMSU, July 2001.
[27] NATO Standardisation Agreement (STANAG) 4539, Technical Standards For Non-Hopping HF Communications Waveforms.
[28] NATO STANAG 5066, Profile For High Frequency (HF) Radio Data Communications.
[29] Ian Poole, Radio Waves and the Ionosphere, November 1999
[30] Moe Wheatley, PathSim User and Technical Guide Ver. 1.0 Dec, 2000
[31] Mehdi Rostami, Joao Angeja, Joao Tavares and Antonio Navarro, HF Channel Modeling for Real Time Packet Transmission, 2003-04-15
[32] 束锋、吴乐南，《16DAPSK+OFDM及其在数字调幅广播中应用》，电路与系统学报，第6卷第3期，2001年9月
[33] Jan E.M.Nilsson and Timothy C. Giles, Wideband multi-carrier transmission for military HF communication, 1997 IEEE
[34] Timothy C. Giles and Ian Willoughby, Simulation of high frequency voice band radio channels, 1993 IEEE
[35] R.J.Miller&R.C.Lock, OFDM design considerations using the HF fading channel, 1995 IEE
[36] A F Kurpiers, Improved channel estimation and demodulation for OFDM on HF ionospheric channels, 2000 IEE
[37] IEEE Std 802.11a/D7.0-1999, Part11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: High Speed Physical Layer in the 5GHz Band.
[38] IEEE Std 802.16: Air Interface for Fixed Broadband Wireless Access Systems
[39] Angela Doufexi, Simon Armour, Andrew Nix, and Mark Beach, Evaluating the Physical Layer Performance of an OFDM candidate for Fourth Generation Networks, IST SATURN
[40] European Telecommunications Standards Institute, ETS 300 744: Digital Video Broadcasting (DVB-T).
[41] ETSI, "Broadband Radio Access Networks (BRAN): HIPERLAN type 2 technical specification: Physical (PHY) layer," August 1999.
[42] IEEE 802.16.3.p-00/33. "OFDM/OFDMA PHY proposal" Yossi Segal, RunCom Technologies.
[43] John W.Nieto, ITERATIVE EQUALIZATION AND DECODING OF STANAG 4539 9600 BPS HF WAVEFORMS, Harris Corporation, RF Communications Division
[44] Vladimir N. Ivanov. Arthur A. Lanne. Igor V. Moroz, Oleg B. Semienov, Sergey N. Frolov. Implementing Vcoder and HF ModemAlgorithms Using the TMS320C31 DSP, September 1996
[45] S.C.Cook, M.C.Gill. T.C.Giles "A High-Speed HF Parallel-Tone Modem ". "HF Radio Systems,and Techniques", 4-7 July 1994, Conference Publication, No.392, pp. 175-181.
[46] T C Giles, A high-speed modem with built-in HF noise tolerance, July 1994 IEE
[47] TIMOTHY C. GILES. "ON THE DESIGN OF HF RADIO MODEMS", Doctor Thesis, December. 1995
[48] Ungerboeck G (1982), "Channels coding with multi-level phase signals", IEEE Trans. Inform.Theory, IT-28, Jan. 1982, pp.55-67.
[49] T C Giles, HF MODEM DESIGN FOR EXTREMELY HIGH SIMULTANEOUS DOPPLER AND DELAY SPREADS
[50] Jan E.M, Nlisson and T C.Giles, Wideband multi-carrier transmission for military HF communication, 1997 IEEE
[51] T.J. Willink, N.C.Davies, M.J. Angling, V. Jodalen and B. Lundborg, "Robust HF data communications at high latitudes", IEE Proceedings of Microwave, Antennasand Propagation, Vol. 146, No. 4, August 1999.