基于COFDM的车载型无线移动图像传输系统的设计
摘要
随着通信技术的发展,无线视频传输技术已广泛应用于工业和社会生活的各个领域.公共安全领域的救援和监控要求在高速移动的环境中实现视频、语音、数据等宽带多媒体业务的实时、同步传输。而无线信道带宽资源有限,干扰因素多,视频信号数据量大,实时性要求高。针对这些问题,本文探讨将COFDM技术用于高速移动条件下无线图像传输的实现方案。
文中介绍了COFDM的技术原理、主要优点及存在的不足,重点讨论了基于COFDM技术的图像传输系统的整体设计。COFDM系统是信道编码和OFDM技术的结合,重点介绍了信道编码,包括外编码和内编码,数据交织,包括外交织和内交织,讨论了系统如何通过信道编码来对抗无线信道带来的各种衰落。
系统采用结构化设计,根据系统整体要求和指标分配将系统分为多个模块,包括编码模块,数据复用模块,COFDM调制模块,滤波器单元,低噪放单元等。文中描述了各模块单元的功能,并结合具体技术指标给出了各个单元电路的设计。
系统在硬件实现后进行了一系列测试和环境试验,进一步验证了系统设计的合理性和可靠性.测试结果表明,系统基本满足了设计要求,实现了在典型城市环境下,在150km/h的移动速度下图像的可靠传输。目前,该系统已广泛应用于指挥,抢险等公共安全领域。
With the development of communication technology, wireless video transmission technology has been widely used in industry and in all areas of social life. The rescue and monitoring in the field of Public safety require the transmission of the video, the voice and data in real-time and synchronously. However,there are limited resources and much interfernce in wireless channnels,and heavy traffic and high real-time demand for video signals.Aiming at these problems,this thesis analyzes how COFDM technelogy is used to implement wireless video transmission under the condition of high moving speed.
After briefly intruducing COFDM technelogy theories,its major advantages and shortcomings,this thesis focuses on the whole design of COFDM-baced clear video transmission system. The COFDM system is the union of channel coding and the OFDM technology.The article introduced the channel coding and discussed how the system to resist each kind of decline through the channel coding.
The system uses the structurization design. According to the system whole request and the target assignmen,the system is divided in to many modules, including the code module, the data multiplying module, the COFDM modulation module, the filter unit, the low noise amplifier unit and so on.The article described various modules unit function and gave each unit electric circuit's design.
After a series of hardware tests and environmental testing, the system further verifies the rationality and feasibility of the design. Test results show that the system basically meets the design requirements, the image can transport at the speed of 150km/h reliablely in a typical urban environment. Currently, the system has been widely used in command, rescue and other public safety fields.
文中介绍了COFDM的技术原理、主要优点及存在的不足,重点讨论了基于COFDM技术的图像传输系统的整体设计。COFDM系统是信道编码和OFDM技术的结合,重点介绍了信道编码,包括外编码和内编码,数据交织,包括外交织和内交织,讨论了系统如何通过信道编码来对抗无线信道带来的各种衰落。
系统采用结构化设计,根据系统整体要求和指标分配将系统分为多个模块,包括编码模块,数据复用模块,COFDM调制模块,滤波器单元,低噪放单元等。文中描述了各模块单元的功能,并结合具体技术指标给出了各个单元电路的设计。
系统在硬件实现后进行了一系列测试和环境试验,进一步验证了系统设计的合理性和可靠性.测试结果表明,系统基本满足了设计要求,实现了在典型城市环境下,在150km/h的移动速度下图像的可靠传输。目前,该系统已广泛应用于指挥,抢险等公共安全领域。
With the development of communication technology, wireless video transmission technology has been widely used in industry and in all areas of social life. The rescue and monitoring in the field of Public safety require the transmission of the video, the voice and data in real-time and synchronously. However,there are limited resources and much interfernce in wireless channnels,and heavy traffic and high real-time demand for video signals.Aiming at these problems,this thesis analyzes how COFDM technelogy is used to implement wireless video transmission under the condition of high moving speed.
After briefly intruducing COFDM technelogy theories,its major advantages and shortcomings,this thesis focuses on the whole design of COFDM-baced clear video transmission system. The COFDM system is the union of channel coding and the OFDM technology.The article introduced the channel coding and discussed how the system to resist each kind of decline through the channel coding.
The system uses the structurization design. According to the system whole request and the target assignmen,the system is divided in to many modules, including the code module, the data multiplying module, the COFDM modulation module, the filter unit, the low noise amplifier unit and so on.The article described various modules unit function and gave each unit electric circuit's design.
After a series of hardware tests and environmental testing, the system further verifies the rationality and feasibility of the design. Test results show that the system basically meets the design requirements, the image can transport at the speed of 150km/h reliablely in a typical urban environment. Currently, the system has been widely used in command, rescue and other public safety fields.
引文
[1]邱玲,朱近康,孙葆根,等.第三代移动通信技术.北京：人民邮电出版社,2001.4-5
[2]Zhu Haiying,Bouchard L,Boucher L M.Advantages of Hybrid OFDM System in 3G and Beyond.2003 International Conference on Communication Technology.Beijing,China,2003,2:940-944
[3]张海滨.正交频分复用的基本原理与关键技术.北京：国防工业出版社,2006.68-77
[4]曹志刚,钱亚生.现代通信原理.北京：清华大学出版社,1992.371-392
[5]Rappaport T S.Wireless Communications:Principles and Practice(Second Edition,影印版).北京：电子工业出版社,2004.203-204
[6]曹秀英,耿嘉,沈平,等.无线局域网安全系统.北京：电子工业出版社,2004.3-5
[7]ZouWY,Wu Yiyan.COFDM:an overview.IEEE Transactions on Broadcasting,1995,41(1):1-8
[8]Ormondroyd R F,Maxey J J,Alsusa E.COFDM-an alternative strategy for future-generation mobile communications.IEE Colloquium,1996,115:8/1-8/6
[9]Weinstein S B,Ebert P M.Data transmission by frequency-division multiplexing using the discrete Fourier transform.IEEE Transactions on Communication,1971,19(5):628-634
[10]Cooley J W,Tukey J W.An Algorithm for the Machine Calculation of Complex Fourier Series.Mathematics of Computation,1965,19:297-301
[11]程佩青.数字信号处理教程.北京：清华大学出版社,2001.138-172
[12]Winograd S.On computing the discrete Fourier transform.Proceedings of the National Academy of Sciences of the United States of America,1976,73(4):1005-1006
[13]谭泽富,聂祥飞,王海宝.OFDM的关键技术及应用.成都：西南交通大学出版社,2005.5-8
[14]Jeruchim M C,Balaban P,Shanmugan K S.Simulation of Communication Systems: Modeling,Methodology,and Techniques(Second Edition).New York:Kluwer Academic Publishers,2002.553-558
[15]A.E.Jones and T.A.Wilkinson. Combined codeing for error control and increased robustness to system nonlinearities in OFDM[J].Proc of IEEE VCT 96,pp. 904-908,1996.
[16]Molisch A F.Wideband Wireless Digital Communications(影印版).北京：电子工业出版社,2002.41-45
[17]张宗橙.纠错编码原理和应用.北京：电子工业出版社,2003.119-132
[18]European Telecommunications Standard Institute.EN300 744.Digital Video Broadcasting:Framing structure,channel coding and modulation for digital terrestrial television.ETSI,2004-11
[19]Massey J L.Shift-Register Synthesis and BCH Decoding.IEEE Transactions on Information Theory,1969,IT-15:122-127
[20]Chien R T.Cyclic Decoding Procedure for the Bose-Chaudhuri-Hocquenghem Codes.IEEE Transactions on Information Theory,1964,IT-10:357-363
[21]Forney G D.On decoding BCH codes.IEEE Transactions on Information Theory,1965,IT-11:549-557
[22]He Zhi-yong,Ge Jian-hua,Geng Shu-jian,et al.An improved look-up table predistortion technique for HPA with memory effects in OFDM systems.IEEE Transactions on Broadcasting,2006,52(1):87-91
[23]Manne G K,Yao Tim.On the predistortion technique for improving transmission linearity of OFDM system.2004 IEEE 60th Vehicular Technology Conference, VTC2004-Fall:Wireless Technologies for Global Security.Los Angeles,USA,2004,60(6):3876-3879
[24]Mahil S,Sesay A B.Rational Function Based Predistorter for Traveling Wave Tube Amplifiers.IEEE Transactions on Broadcasting,2005,51(1):77-83
[25]Park I S,Powers E J,Xu G.Parallel adaptive predistortion for RF power amplifier linearization.Proceedings of the 1997 IEEE Global Telecommunications Conference.Phoenix,USA,1997,1:82-86
[26]Rapp C.Effects of HPA-Nonlinearity on an 4-DPSK/OFDM-Signal for a digital sound broadcasting system.In ECSC-2,Proceedings of the Second European Conference On Satellite Communications.Liege,Belgium,1991.176-184
[27]Haykin S.Adaptive Filter Theory(Third Edition,影印版).北京：电子工业出版社,1998.562-587
[28]佟学俭.OFDM移动通信技术原理与应用[M].北京：人民邮电出版社,2003.
[29]樊昌信.通信原理(第5版)[M].北京：国防工业出版社,2003.
[30]Commission of European Communities.COST207:Digital Land Mobile Radio Communication (Final Report).Luxembourg,1989
[31]陈运,信息论与编码,电子工业出版社,2002
[32]Xiaodong Li and Leonard J. Cimini. Effects of Clipping and Filtering on the Performance of OFDM[A]. IEEE Vehicular Technology Conference[C],Volume 3, 4-7 Page(s):1634-1638 May 1997.
[33]R. van Nee and R. Prasad. OFDM for Wireless Multimedia Communications [M]. MA:Artech House,2000.
[34]Osamu MUTA and Yoshihiko AKAIWA. A Peak Power Reduction Scheme with Phase-control of Clustered Parity-Carriers for a Systematic Block-Coded OFDM Signal [A]. IEEE Vehicular Technology Conference [C],2003-Fall,58th Volume 1,6-9 Page(s):562-566 Vol.1, Oct 2003.
[35]周强等,高压电力线载波COFDM通信及编码技术的应用研究,继电器,2004(8)
[2]Zhu Haiying,Bouchard L,Boucher L M.Advantages of Hybrid OFDM System in 3G and Beyond.2003 International Conference on Communication Technology.Beijing,China,2003,2:940-944
[3]张海滨.正交频分复用的基本原理与关键技术.北京：国防工业出版社,2006.68-77
[4]曹志刚,钱亚生.现代通信原理.北京：清华大学出版社,1992.371-392
[5]Rappaport T S.Wireless Communications:Principles and Practice(Second Edition,影印版).北京：电子工业出版社,2004.203-204
[6]曹秀英,耿嘉,沈平,等.无线局域网安全系统.北京：电子工业出版社,2004.3-5
[7]ZouWY,Wu Yiyan.COFDM:an overview.IEEE Transactions on Broadcasting,1995,41(1):1-8
[8]Ormondroyd R F,Maxey J J,Alsusa E.COFDM-an alternative strategy for future-generation mobile communications.IEE Colloquium,1996,115:8/1-8/6
[9]Weinstein S B,Ebert P M.Data transmission by frequency-division multiplexing using the discrete Fourier transform.IEEE Transactions on Communication,1971,19(5):628-634
[10]Cooley J W,Tukey J W.An Algorithm for the Machine Calculation of Complex Fourier Series.Mathematics of Computation,1965,19:297-301
[11]程佩青.数字信号处理教程.北京：清华大学出版社,2001.138-172
[12]Winograd S.On computing the discrete Fourier transform.Proceedings of the National Academy of Sciences of the United States of America,1976,73(4):1005-1006
[13]谭泽富,聂祥飞,王海宝.OFDM的关键技术及应用.成都：西南交通大学出版社,2005.5-8
[14]Jeruchim M C,Balaban P,Shanmugan K S.Simulation of Communication Systems: Modeling,Methodology,and Techniques(Second Edition).New York:Kluwer Academic Publishers,2002.553-558
[15]A.E.Jones and T.A.Wilkinson. Combined codeing for error control and increased robustness to system nonlinearities in OFDM[J].Proc of IEEE VCT 96,pp. 904-908,1996.
[16]Molisch A F.Wideband Wireless Digital Communications(影印版).北京：电子工业出版社,2002.41-45
[17]张宗橙.纠错编码原理和应用.北京：电子工业出版社,2003.119-132
[18]European Telecommunications Standard Institute.EN300 744.Digital Video Broadcasting:Framing structure,channel coding and modulation for digital terrestrial television.ETSI,2004-11
[19]Massey J L.Shift-Register Synthesis and BCH Decoding.IEEE Transactions on Information Theory,1969,IT-15:122-127
[20]Chien R T.Cyclic Decoding Procedure for the Bose-Chaudhuri-Hocquenghem Codes.IEEE Transactions on Information Theory,1964,IT-10:357-363
[21]Forney G D.On decoding BCH codes.IEEE Transactions on Information Theory,1965,IT-11:549-557
[22]He Zhi-yong,Ge Jian-hua,Geng Shu-jian,et al.An improved look-up table predistortion technique for HPA with memory effects in OFDM systems.IEEE Transactions on Broadcasting,2006,52(1):87-91
[23]Manne G K,Yao Tim.On the predistortion technique for improving transmission linearity of OFDM system.2004 IEEE 60th Vehicular Technology Conference, VTC2004-Fall:Wireless Technologies for Global Security.Los Angeles,USA,2004,60(6):3876-3879
[24]Mahil S,Sesay A B.Rational Function Based Predistorter for Traveling Wave Tube Amplifiers.IEEE Transactions on Broadcasting,2005,51(1):77-83
[25]Park I S,Powers E J,Xu G.Parallel adaptive predistortion for RF power amplifier linearization.Proceedings of the 1997 IEEE Global Telecommunications Conference.Phoenix,USA,1997,1:82-86
[26]Rapp C.Effects of HPA-Nonlinearity on an 4-DPSK/OFDM-Signal for a digital sound broadcasting system.In ECSC-2,Proceedings of the Second European Conference On Satellite Communications.Liege,Belgium,1991.176-184
[27]Haykin S.Adaptive Filter Theory(Third Edition,影印版).北京：电子工业出版社,1998.562-587
[28]佟学俭.OFDM移动通信技术原理与应用[M].北京：人民邮电出版社,2003.
[29]樊昌信.通信原理(第5版)[M].北京：国防工业出版社,2003.
[30]Commission of European Communities.COST207:Digital Land Mobile Radio Communication (Final Report).Luxembourg,1989
[31]陈运,信息论与编码,电子工业出版社,2002
[32]Xiaodong Li and Leonard J. Cimini. Effects of Clipping and Filtering on the Performance of OFDM[A]. IEEE Vehicular Technology Conference[C],Volume 3, 4-7 Page(s):1634-1638 May 1997.
[33]R. van Nee and R. Prasad. OFDM for Wireless Multimedia Communications [M]. MA:Artech House,2000.
[34]Osamu MUTA and Yoshihiko AKAIWA. A Peak Power Reduction Scheme with Phase-control of Clustered Parity-Carriers for a Systematic Block-Coded OFDM Signal [A]. IEEE Vehicular Technology Conference [C],2003-Fall,58th Volume 1,6-9 Page(s):562-566 Vol.1, Oct 2003.
[35]周强等,高压电力线载波COFDM通信及编码技术的应用研究,继电器,2004(8)