直接中频采样软件无线电接收机的实现研究
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摘要
在无线通信系统多标准、多体制以及无线电频谱资源的缺乏背景下，对无线通信系统的互通性要求增加，传统无线通信系统已难以适应发展的需要。软件无线电技术为解决上述问题提供了一个可行的方法，成为人们研究的热点。但现阶段由于电子器件以及技术上的不足，理想的软件无线电还无法实现，因此人们在寻找一种折衷可行的方法。本文研究的直接中频采样软件无线电接收机系统就是软件无线电系统一种现阶段可行的方案。
首先，论述了软件无线电的基本原理。介绍了软件无线电的起源、概念、特点、国内外研究现状和发展方向，分析了根据不同的采样方式确定的不同的软件无线电系统的基本结构，包括射频全宽开低通采样软件无线电结构、射频直接带通采样软件无线电结构和宽带中频带通采样软件无线电结构，以及软件无线电中的关键技术。
其次，通过全面比较分析几种信号采样方式，选定了适合于现阶段的带通采样方式。结合软件无线电的体系结构和宽带中频带通采样的思想，提出了现阶段可行的直接中频采样软件无线电接收机的系统结构框图，并且分析了各个模块的工作原理，包括射频处理、中频处理以及基带处理等。射频前端预处理采用成熟的超外差技术，选择合适的中频和带宽，得到合适的A／D采样速率。
然后，分析研究了中频处理部分的实现。结合系统性能的要求，选择了AD6640和HSP50214B为A／D转换器和专用可编程数字下变频器。重点分析了AD6640和HSP50214B的结构功能、应用设计以及外围接口电路的连接。
最后，讨论了基带处理部分的实现。由于GMSK良好的频谱特性以及恒包络特性，本系统选择GMSK为解调方式，并详细分析了GMSK解调的原理和不同的解调算法以及实现原理。通过分析GMSK几种算法的优越性以及系统对处理的需求，选择基于正交解调的基带时延检波算法以及TMS320VC5402进行基带处理。并且分析了TMS320VC5402的硬件结构，给出了TMS320VC5402实现的GMSK解调的程序流程图和用CCS软件仿真的波形图。
理论分析和仿真研究表明直接中频采样软件无线电接收机是可行的，而
武汉理工大学硕士学位论文
且具有很强的灵活性，可扩展性。
With the occurrence of multi-standards and poly-systems in wireless communication system, the increase of the requirement of intercourse and the lacking of radio frequency spectrum resource, the traditional wireless communication system cannot be adapted to the relative development. Software radio technology offers a feasible method to solve this problem so as to become a focus of research. Whereas, the deficiency both in electronic device and technology results in that the ideal software radio can hardly be realized and people have to seek a compromising and feasible method. Software radio receiver system based on direct mid-frequency sampling, which is researched in this paper, is one of the feasible software radio system nowadays.
Firstly, the paper presents the basic principles of software radio, introduces the origin, the concept, the features, the research status quo domestically and abroad and the developing direction of the software radio, analyzes the different basic structures of software radio system in terms of different sampling methods, including software radio structure with broadband and low-pass sampling, software radio structure with direct band-pass sampling and the software structure with broadband mid-frequency sampling, and analyzes some key technologies in software radio.
Consequently, through the full comparison of several signal sampling modes, the broadband sampling mode is centered out in adaptation to present application. Combining the software radio system with the idea of broadband mid-frequency sampling, the paper puts forward the feasible structure plot of software radio receiver system based on direct mid-frequency sampling nowadays. Then the working principle of each module is analyzed, including radio frequency processing, middle frequency processing and base-band processing. In the pre-procession of front radio frequency, the super-heterodyne technology which get proper A/D sampling rate through choosing a proper frequency and bandwidth is adopted.
Furtherly, the paper analyses and studies the realization of the mid-frequency processing. According to the requirement of system property, AD6640 and HSP50214B are selected functioning as A/D switcher and specific programming digital downconverter, then
the paper highlights the structures, functions, applications, designs and outer interface circuit connect of the AD6640 and HSP50214B.
Finally, the paper presents the realization of the base-band processing. GMSK is selected as demodulating method for its excellent frequency spectrum characteristics and permanent envelope property. The paper introduces in detail the GMSK demodulation principle, different demodulating algorithm and realizing principle. Through the analysis of advantages of several GMSK arithmetic and requirement of system processing, the base-band time lag demodulating algorithm based on quadrature demodulation and TMS320VC5402 are selected for base-band processing. Furthermore, the paper introduces the basic development of DSP and hardware frame of TMS320VC5402, and provides the program flow chart of GMSK demodulation which realizes with TMS320VC5402 and emulational wave with CCS software.
The theory analysis and emulation research prove that software radio receiver based on direct mid-frequency sampling is feasible, and possesses the strong flexibility and expansibility.
首先，论述了软件无线电的基本原理。介绍了软件无线电的起源、概念、特点、国内外研究现状和发展方向，分析了根据不同的采样方式确定的不同的软件无线电系统的基本结构，包括射频全宽开低通采样软件无线电结构、射频直接带通采样软件无线电结构和宽带中频带通采样软件无线电结构，以及软件无线电中的关键技术。
其次，通过全面比较分析几种信号采样方式，选定了适合于现阶段的带通采样方式。结合软件无线电的体系结构和宽带中频带通采样的思想，提出了现阶段可行的直接中频采样软件无线电接收机的系统结构框图，并且分析了各个模块的工作原理，包括射频处理、中频处理以及基带处理等。射频前端预处理采用成熟的超外差技术，选择合适的中频和带宽，得到合适的A／D采样速率。
然后，分析研究了中频处理部分的实现。结合系统性能的要求，选择了AD6640和HSP50214B为A／D转换器和专用可编程数字下变频器。重点分析了AD6640和HSP50214B的结构功能、应用设计以及外围接口电路的连接。
最后，讨论了基带处理部分的实现。由于GMSK良好的频谱特性以及恒包络特性，本系统选择GMSK为解调方式，并详细分析了GMSK解调的原理和不同的解调算法以及实现原理。通过分析GMSK几种算法的优越性以及系统对处理的需求，选择基于正交解调的基带时延检波算法以及TMS320VC5402进行基带处理。并且分析了TMS320VC5402的硬件结构，给出了TMS320VC5402实现的GMSK解调的程序流程图和用CCS软件仿真的波形图。
理论分析和仿真研究表明直接中频采样软件无线电接收机是可行的，而
武汉理工大学硕士学位论文
且具有很强的灵活性，可扩展性。
With the occurrence of multi-standards and poly-systems in wireless communication system, the increase of the requirement of intercourse and the lacking of radio frequency spectrum resource, the traditional wireless communication system cannot be adapted to the relative development. Software radio technology offers a feasible method to solve this problem so as to become a focus of research. Whereas, the deficiency both in electronic device and technology results in that the ideal software radio can hardly be realized and people have to seek a compromising and feasible method. Software radio receiver system based on direct mid-frequency sampling, which is researched in this paper, is one of the feasible software radio system nowadays.
Firstly, the paper presents the basic principles of software radio, introduces the origin, the concept, the features, the research status quo domestically and abroad and the developing direction of the software radio, analyzes the different basic structures of software radio system in terms of different sampling methods, including software radio structure with broadband and low-pass sampling, software radio structure with direct band-pass sampling and the software structure with broadband mid-frequency sampling, and analyzes some key technologies in software radio.
Consequently, through the full comparison of several signal sampling modes, the broadband sampling mode is centered out in adaptation to present application. Combining the software radio system with the idea of broadband mid-frequency sampling, the paper puts forward the feasible structure plot of software radio receiver system based on direct mid-frequency sampling nowadays. Then the working principle of each module is analyzed, including radio frequency processing, middle frequency processing and base-band processing. In the pre-procession of front radio frequency, the super-heterodyne technology which get proper A/D sampling rate through choosing a proper frequency and bandwidth is adopted.
Furtherly, the paper analyses and studies the realization of the mid-frequency processing. According to the requirement of system property, AD6640 and HSP50214B are selected functioning as A/D switcher and specific programming digital downconverter, then
the paper highlights the structures, functions, applications, designs and outer interface circuit connect of the AD6640 and HSP50214B.
Finally, the paper presents the realization of the base-band processing. GMSK is selected as demodulating method for its excellent frequency spectrum characteristics and permanent envelope property. The paper introduces in detail the GMSK demodulation principle, different demodulating algorithm and realizing principle. Through the analysis of advantages of several GMSK arithmetic and requirement of system processing, the base-band time lag demodulating algorithm based on quadrature demodulation and TMS320VC5402 are selected for base-band processing. Furthermore, the paper introduces the basic development of DSP and hardware frame of TMS320VC5402, and provides the program flow chart of GMSK demodulation which realizes with TMS320VC5402 and emulational wave with CCS software.
The theory analysis and emulation research prove that software radio receiver based on direct mid-frequency sampling is feasible, and possesses the strong flexibility and expansibility.
引文
【1】 Buracchini E. The software radio concept. IEEE Communication Magazine. 2000.38(9): 138～143.
【2】 Walter H.W.Tuttle. Softerware Radio Technology: A European Perspective. IEEE Communications Maganize. 1999(2): 118～123.
【3】 王文艺，黄文，夏牧．软件无线电的新进展．空军工程大学学报(自然科学版)，2002：6～38．
【4】 杨涛，吴启晖，王金龙．软件无线电发展综述．电信科学，2001：25～27．
【5】 Mitola J. Technical Challenges in the Globalization of Software Radio. IEEE Communication Magazine. 1999. 37(2): 84～89.
【6】 杨小牛，楼才义，徐建良．软件无线电原理与应用．北京：电子工业出版社，2001．1．
【7】 钮心忻，杨义先．软件无线电技术与应用．北京：北京邮电出版社，2000．9．
【8】 V.Bose, M.Ismert, M.Welborn et al. Virtual Radio. IEEE JSAC. 1999.17(4): 591～602.
【9】 Joseph Mitola Ⅲ. Software Radio Architecture: Object-Oriented Approaches to Wireless Systems Engineering. John Wiley & Sons, Inc. 2001.
【10】 Mitola J. The Software Radio Architecture. IEEE Communication Magazine.1995.33(5): 26～38.
【11】 Joseph Mitola Ⅲ. Software Radio Architecture Evolution: Foundations, Technology Tradeoffs, and Architecture Implications. IECE Transaction Communication. 2000. E83-B(6): 1165～1173.
【12】 赵荣黎，王庭昌，李承恕译．软件无线电体系结构．北京：机械工业出版社，2003．1．1．
【13】 Noll J, Buracchini E. Software Radio-a key technology for adaptive access. Wireless communications & mobile computer. 2002.10(2): 789～798.
【14】 颜彪，周平，许宗泽．软件无线电的关键技术．电力系统通信．2001(6)：29～33．
【15】 刘星成，罗恒宏．软件无线电的关键技术及平台构建初探．无线电通信技术，2000．1．
【16】 樊昌信，詹道庸，徐炳祥等．通信原理(第五版)．北京：国防工业出版社，2001．3．
【17】 Abu-Al-Saud WA, Stuber GL. Modified CIC filter for sample rate conversion in software radio systems. IEEE Signal Processing Letters. 2003. 10(5): 152～154.
【18】 王文桂，肖晓劲．通信接收机：DSP、软件无线电和设计(第三版)．北京：人民邮电出版，2003．3．
【19】 张睿，李维英，李建东．带通采样技术在软件接收机中的应用．西安电子科技大学学报(自然科学版)．2000(6)：326～329．
【20】 Daneshgaran F, Laddomada M. Transceiver front-end technology for software radio
implementation of wideband satellite communication systems. Wireless personal communication. 2003. 24(2): 99～121.
【21】 Mitola J. Cognitive radio for flexible mobile multimedia communications. Mobile Networks & Applications. 2001.6(5): 435～441.
【22】 沈兰荪．高速数据采集系统的原理与应用(第1版)．北京：人民邮电出版社，1996．1．
【23】 EB. Kenington, L.Astier. Power Consumption of A/D Converts for Software Radio Applications. IEEE Transactions on Vehicular Technology. 2000.49(2): 643～650.
【24】 Sanada Y, Ikehara M. Digital compensation scheme for coefficient errors of complex filter bank parallel A/D converter in low-IF receivers. IEICE Transactions on Communications. 2002(12): 2656～2662.
【25】 Morelos Zaragoza R, Haruyama S, Abe M, et al. A software radio receiver with direct conversion and its digital processing. IEICE Transactions on Communications. 2002: 2741～2749.
【26】 Laddomada M. Reconfiguration issues of future mobile software radio platforms. Wireless communications & mobile computer. 2002.10(2): 815～826.
【27】 徐彤．中频接收机数字化设计中的几个关键问题．电讯技术．2001(4)：91～94．
【28】 王金础，杨正远．一种高性能数字中频接收机的设计及实现．现代雷达．2002(1)：71～73．
【29】 周昊，宋文涛等．中频软件无线电系统的实现方案．通信技术．1999(4)：61～65．
【30】 曾涛．一种新的中频采样滤波器的设计与实现．电子学报．2000(6)：51～54．
【31】 戴庆芬．中频数字化及数字式正交解调．电讯技术．1996(5)：1～5．
【32】 吴启辉，莫永成．第三代移动通信系统中的软件无线电技术．移动通信，2000．2．
【33】 Benventuo. N, Bisaglia.P, Jones.A.E et al. Complex Non-coherent Receivers for GMSK Signals. IEEE Journal on Selected Areas in Communications. 1999.17(11): 1876～1885.
【34】 庞宝茂．软件无线电及其在第三代移动通信中的应用．通信技术，2001．1．
【35】 尤克．现代数字移动通信原理及实用技术．北京：北京航空航天大学出版社，2001．3．
【36】 吴伟陵．移动通信中的关键技术．北京：北京邮电大学，2001．8．
【37】 N. Youssef, A.Ghazel, S.Tabbane et al. Software Development for DSP Implementation of GMSK Modulation for GSM Transceiver. IEEE AFRICON.1999. 1: 321～326.
【38】 张涛．软件无线电中的DSP技术．湖南工程学学报，2002．6．
【39】 戴逸民．基于DSP的现代电子系统设计．北京：电子工业出版社，2002．12．
【40】 李刚．数字信号处理器的原理及其开发应用．天津：天津大学出版社，2000．4．
【41】 彭启琮，李玉柏，管庆．DSP的发展与应用．北京：高教出版社，2002．5．
【42】 Mitola J, Zvonar Z. Software and DSP in radio. IEEE Communications Maganize.
1999：68～82．
【43】 苏涛，卢光跃，张林让等．DSP实用技术．西安：西安电子科技出版社，2002．6．
【44】 张雄伟．DSP集成开发与应用实例．北京：电子工业出版社，2002．6．
【45】 彭启琮，李玉柏．TMS320C54X实用教程．成都：电子科技大学出版社，2000．4．
【46】 James E. Gunn, Kenneth S.Barron, William Ruczczyk. A Low-Power DSP Core-Based Software Radio Architecture. IEEE Journal on Selected Areas in Communications. 1999. 17(4): 601～612.
【47】 Valkama M, Pirskanen J, Renfors M. Signal processing challenges for applying software radio principles in future wireless terminals: an overview. International journal of communication systems. 2002.15(2): 741～769.
【48】 朱铭浩，赵勇，甘泉．DSP应用系统设计．北京：电子工业出版社，2002．10．
【49】 Neiyer S. Correal, R.Michael Buehrer, Brian D.Woener. A DSP-based DS-CDMA multiuser receiver employing partial parallel interference cancellation. IEEE Jounal on Selected Areas in Cmmunications. 1999.17(4): 613～630.
【50】 姚天任，江太辉．数字信号处理．武汉：华中理工大学出版社，2001．8．
【51】 Takafumi Yamaji, Akira Yasuda, Hiroshi Tanimoto et al. A Digital-to-RF Converter Architecture Suitable for a Digital-to-RF Direct-Conversion Software Defined Radio Transmitter. IECE Transaction Communication. 2000. E83-B(6): 1254～1259.
【2】 Walter H.W.Tuttle. Softerware Radio Technology: A European Perspective. IEEE Communications Maganize. 1999(2): 118～123.
【3】 王文艺，黄文，夏牧．软件无线电的新进展．空军工程大学学报(自然科学版)，2002：6～38．
【4】 杨涛，吴启晖，王金龙．软件无线电发展综述．电信科学，2001：25～27．
【5】 Mitola J. Technical Challenges in the Globalization of Software Radio. IEEE Communication Magazine. 1999. 37(2): 84～89.
【6】 杨小牛，楼才义，徐建良．软件无线电原理与应用．北京：电子工业出版社，2001．1．
【7】 钮心忻，杨义先．软件无线电技术与应用．北京：北京邮电出版社，2000．9．
【8】 V.Bose, M.Ismert, M.Welborn et al. Virtual Radio. IEEE JSAC. 1999.17(4): 591～602.
【9】 Joseph Mitola Ⅲ. Software Radio Architecture: Object-Oriented Approaches to Wireless Systems Engineering. John Wiley & Sons, Inc. 2001.
【10】 Mitola J. The Software Radio Architecture. IEEE Communication Magazine.1995.33(5): 26～38.
【11】 Joseph Mitola Ⅲ. Software Radio Architecture Evolution: Foundations, Technology Tradeoffs, and Architecture Implications. IECE Transaction Communication. 2000. E83-B(6): 1165～1173.
【12】 赵荣黎，王庭昌，李承恕译．软件无线电体系结构．北京：机械工业出版社，2003．1．1．
【13】 Noll J, Buracchini E. Software Radio-a key technology for adaptive access. Wireless communications & mobile computer. 2002.10(2): 789～798.
【14】 颜彪，周平，许宗泽．软件无线电的关键技术．电力系统通信．2001(6)：29～33．
【15】 刘星成，罗恒宏．软件无线电的关键技术及平台构建初探．无线电通信技术，2000．1．
【16】 樊昌信，詹道庸，徐炳祥等．通信原理(第五版)．北京：国防工业出版社，2001．3．
【17】 Abu-Al-Saud WA, Stuber GL. Modified CIC filter for sample rate conversion in software radio systems. IEEE Signal Processing Letters. 2003. 10(5): 152～154.
【18】 王文桂，肖晓劲．通信接收机：DSP、软件无线电和设计(第三版)．北京：人民邮电出版，2003．3．
【19】 张睿，李维英，李建东．带通采样技术在软件接收机中的应用．西安电子科技大学学报(自然科学版)．2000(6)：326～329．
【20】 Daneshgaran F, Laddomada M. Transceiver front-end technology for software radio
implementation of wideband satellite communication systems. Wireless personal communication. 2003. 24(2): 99～121.
【21】 Mitola J. Cognitive radio for flexible mobile multimedia communications. Mobile Networks & Applications. 2001.6(5): 435～441.
【22】 沈兰荪．高速数据采集系统的原理与应用(第1版)．北京：人民邮电出版社，1996．1．
【23】 EB. Kenington, L.Astier. Power Consumption of A/D Converts for Software Radio Applications. IEEE Transactions on Vehicular Technology. 2000.49(2): 643～650.
【24】 Sanada Y, Ikehara M. Digital compensation scheme for coefficient errors of complex filter bank parallel A/D converter in low-IF receivers. IEICE Transactions on Communications. 2002(12): 2656～2662.
【25】 Morelos Zaragoza R, Haruyama S, Abe M, et al. A software radio receiver with direct conversion and its digital processing. IEICE Transactions on Communications. 2002: 2741～2749.
【26】 Laddomada M. Reconfiguration issues of future mobile software radio platforms. Wireless communications & mobile computer. 2002.10(2): 815～826.
【27】 徐彤．中频接收机数字化设计中的几个关键问题．电讯技术．2001(4)：91～94．
【28】 王金础，杨正远．一种高性能数字中频接收机的设计及实现．现代雷达．2002(1)：71～73．
【29】 周昊，宋文涛等．中频软件无线电系统的实现方案．通信技术．1999(4)：61～65．
【30】 曾涛．一种新的中频采样滤波器的设计与实现．电子学报．2000(6)：51～54．
【31】 戴庆芬．中频数字化及数字式正交解调．电讯技术．1996(5)：1～5．
【32】 吴启辉，莫永成．第三代移动通信系统中的软件无线电技术．移动通信，2000．2．
【33】 Benventuo. N, Bisaglia.P, Jones.A.E et al. Complex Non-coherent Receivers for GMSK Signals. IEEE Journal on Selected Areas in Communications. 1999.17(11): 1876～1885.
【34】 庞宝茂．软件无线电及其在第三代移动通信中的应用．通信技术，2001．1．
【35】 尤克．现代数字移动通信原理及实用技术．北京：北京航空航天大学出版社，2001．3．
【36】 吴伟陵．移动通信中的关键技术．北京：北京邮电大学，2001．8．
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