GSM下行广播信道解调系统设计与实现
摘要
GSM移动通信系统在我国经过长期的发展，目前已经成为运用最广泛的移动通信系统。虽然3G通信系统已经在我国商用，但由于其成本及技术等方面的限制，在未来几年内，运营商仍将投入大量的财力对GSM移动通信网络进行维护和优化。在实际工程中，架设GSM直放站无疑成为解决基站覆盖盲区的最佳方式。近几年来随着模拟直放站被数字直放站取代，大量的GSM数字直放站运用于GSM网络中，在实现小容量大覆盖的目标时也对整个GSM网络造成了负面影响。
本论文正是基于上述背景，在传统的GRRU（GSM数字射频拉远）系统中加入广播信道解调模块。通过对GSM下行广播信道的解调提取出GSM小区跳频信息，预期实现GRRU与基站的同步跳频，以此来提高GRRU的工作性能，降低GRRU对GSM网络的负面影响。
本论文第一章介绍了GSM移动通信系统的发展现状以及本课题的研究背景和研究意义，并对文章的组织结构进行了总结；第二章详细介绍了GSM通信系统基带相关的理论知识；第三章讨论了GMSK调制技术及系统中所采用的同步算法，并利用MATLAB对GMSK调制过程和同步算法进行了仿真。第四章对整个GSM广播信道解调系统进行了详细介绍，重点介绍了GMSK解调和信道译码模块的实现方式；第五章用FPGA实现了各个模块的逻辑功能，并在基于软件无线电的数字信号处理平台上进行调试。最后对全文进行了总结，提出了前期工作的改进点和后续工作安排。
With its long-term development history in China, GSM mobile communicationsystem has become the most widely used communication system in the present days. The3G communication system has been used in business. However, due to the restrictions of3Gs cost and technology, operators still have to pay much for the maintenance andoptimization of GSM in the next few years. Building repeaters is the best solution toenhance network coverage in actual construction. In recent years, with the traditionalanalog repeater being replaced by digital repeater, a large number of GSM digital repeatershave been used in GSM network. The GSM digital repeater has achieved the goal ofnetwork coverage with a small capacity, but it makes adverse impact on GSM network aswell.
Based on the above background, this paper brings broadcast channel demodulationmodule into traditional GRRU (GSM digital remote radio unit) system. The system isexpected to make the frequency-hopping synchronized with base station by abstractingfrequency-hopping information of GSM cell from demodulating GSM downlink broadcastchannel. This will help to improve GRRU work performance and reduce its adverse impacton GSM network.
In this paper, Chapter1includes the development status of GSM communicationsystem, the significance and background of the research project, and a summary of theorganizational structure of the present research. Chapter2details the GSM communicationsystem with the theoretical knowledge of baseband. Chapter3discusses the technique ofGMSK modulation and the synchronization algorithm in system, and simulates GMSKmodulation and synchronization algorithm by MATLAB. Chapter4introduces the GSMbroadcast channel demodulation system in detail and focuses on the implementation ofGMSK demodulation and channel decoding module. In Chapter5, each module’s logicfunction is implemented by FPGA and debugged on the digital signal processing platformbased on software radio. The research ends up with a summary of the thesis and deficiencies of previous work which gives directions for future work.
本论文正是基于上述背景，在传统的GRRU（GSM数字射频拉远）系统中加入广播信道解调模块。通过对GSM下行广播信道的解调提取出GSM小区跳频信息，预期实现GRRU与基站的同步跳频，以此来提高GRRU的工作性能，降低GRRU对GSM网络的负面影响。
本论文第一章介绍了GSM移动通信系统的发展现状以及本课题的研究背景和研究意义，并对文章的组织结构进行了总结；第二章详细介绍了GSM通信系统基带相关的理论知识；第三章讨论了GMSK调制技术及系统中所采用的同步算法，并利用MATLAB对GMSK调制过程和同步算法进行了仿真。第四章对整个GSM广播信道解调系统进行了详细介绍，重点介绍了GMSK解调和信道译码模块的实现方式；第五章用FPGA实现了各个模块的逻辑功能，并在基于软件无线电的数字信号处理平台上进行调试。最后对全文进行了总结，提出了前期工作的改进点和后续工作安排。
With its long-term development history in China, GSM mobile communicationsystem has become the most widely used communication system in the present days. The3G communication system has been used in business. However, due to the restrictions of3Gs cost and technology, operators still have to pay much for the maintenance andoptimization of GSM in the next few years. Building repeaters is the best solution toenhance network coverage in actual construction. In recent years, with the traditionalanalog repeater being replaced by digital repeater, a large number of GSM digital repeatershave been used in GSM network. The GSM digital repeater has achieved the goal ofnetwork coverage with a small capacity, but it makes adverse impact on GSM network aswell.
Based on the above background, this paper brings broadcast channel demodulationmodule into traditional GRRU (GSM digital remote radio unit) system. The system isexpected to make the frequency-hopping synchronized with base station by abstractingfrequency-hopping information of GSM cell from demodulating GSM downlink broadcastchannel. This will help to improve GRRU work performance and reduce its adverse impacton GSM network.
In this paper, Chapter1includes the development status of GSM communicationsystem, the significance and background of the research project, and a summary of theorganizational structure of the present research. Chapter2details the GSM communicationsystem with the theoretical knowledge of baseband. Chapter3discusses the technique ofGMSK modulation and the synchronization algorithm in system, and simulates GMSKmodulation and synchronization algorithm by MATLAB. Chapter4introduces the GSMbroadcast channel demodulation system in detail and focuses on the implementation ofGMSK demodulation and channel decoding module. In Chapter5, each module’s logicfunction is implemented by FPGA and debugged on the digital signal processing platformbased on software radio. The research ends up with a summary of the thesis and deficiencies of previous work which gives directions for future work.
引文
[1]直放站—延伸移动通信网[J].中国无线电管理，2003(10).
[2]韩实，沈保锁，王新乐.数字下变频器在现场可编程门阵列中实现[J].电子测量技术，2006(01).
[3]李建东，郭梯云，邬国扬.移动通信[M].西安:西安电子科技大学出版社，2006.237
[4]3GPP Ts05.02V7.7.0(Release1999). Multiplexing and multiple access on the radio path[s].
[5]孙孺石，丁怀元，穆万里，王泽权.GSM数字移动通信工程[M].北京：人民邮电出版社，1995.192-193.
[6]张威.GSM网络优化[M].中国移动通信公司，2003.178-179.
[7]3GPP TS05.01V8.9.0(Release1999).Physical layer on the radio path; General description [S].
[8]田斌，贴翊，任光亮译.无线通信[M].北京：电子工业出版社，2008.395.
[9] B. Sklar著.徐平平等译.数字通信——基础与应用[M].北京：电子工业出版社，2002.360.
[10]冯玉珉.通信系统原理[M].清华大学出版社，2006.
[11]李锋.GSM跳频数字直放站[D].厦门：厦门大学，2009.15-17.
[12]韩斌杰. GSM原理及其网络优化[M].北京：机械工业出版社，2005.
[13] A. Baier, et al,” Bit Synchronization and Timing Sensitivity in Adaptive Vitebri Equalizers ForNarrow-Band TDMA Mobile Radio Systems”[C].Vehicular Technology Conference. IEEE38th.1988.377-384.
[14]900/1800M TDMA数字蜂窝移动通信网——无线接口第二阶段物理层部分[S].
[15] GSM05.04version8.l(Release l999). Digital cellular telecommunications system; Modulation[S].
[16]田耘，徐文波，张延伟等编著.无线通信FPGA设计[M].北京：电子工业出版社，2008.275-276.
[17]张德丰等.MATLAB通信工程仿真[M].北京：机械工业出版社，2010.307.
[18]关雪梅，王晓东.快速傅里叶变换（FFT）与小波变换技术[J].牡丹江师范学院学报（自然科学版），2002(4)：19-20.
[19]张浩，钟子发，王红军.GSM公共信道中FCCH的同频分离与捕获[J]．通信对抗，2006(1)：36-38.
[20]刘继武.GSM空中信号截取与移动台定位技术研究[D].南京：东南大学，2004.
[21]夏玲.GSM/GPRS系统物理层算法仿真及基于ZSP核的优化实现[D].杭州：浙江大学，2006.23-24.
[22]王正生.GSM接收机同步技术研究与基于FPGA和DSP的接收机设计[D].北京：北京交通大学，2009.21.
[23]李子丰.连续相位调制研究及其解调算法的FPGA实现[D].西安：西安电子科技大学，2007.
[24]樊昌信，张甫翊，徐炳祥，吴成柯.通信原理[M].北京：国防工业出版社，2001.46-47.
[25]曹志刚，钱亚生.现代通信原理[M].北京：清华大学出版社，2008.262-264.
[26]张宇等.GSM网络演变为EDGE使用的8PSK调制[J].通讯世界，2006.
[27]Aria G D，Fast Adaptive Equalizers for Narrow Band TDMA Mobile Radio [J].IEEE.Trnas.Vehicular Tech,1991.vol.40(2):392-404.
[28]G Ungerboeck,” Adaptive Maximum-Likelihood Receiver for Carrier-Modulated DataTransmission Systems”[J],IEEE Trans. Commun. May1974.Vol.22(5):624-636.
[29]H. L. Van Trees, Detection，Estimation and Modulation Theory[J],Pt.I.NewYork,Wiley,1968.
[30]G. D. Fonrey,” Maximum-Likelihood Sequence Estimation of Digital Sequences in the Presence ofIntersymbol Interference”[J].IEEE Trans.Info.Theory,May1972.Vol.18(5):363-377.
[31]王新梅，肖国镇.纠错码—原理与方法[M].西安：电子科技大学出版社，2001.
[32]3GPP TS44.018V7.7.0(2006-12).Mobile radio interface layer3specification; Radio ResourceControl(RRC) protocol (Release7)[S].
[33]夏宇闻.数字系统设计—Verilog实现[M].北京：高等教育出版社，2006.16-18.
[34]罗杰，肖看，谭力等. Verilog HDL与数字ASIC设计基础[M].武汉：华中科技大学出版社，2008.
[35]梁成志.Lattice FPGA/CPLD设计[M].北京：人民邮电出版社，2011.10-13.
[36]杨小牛，楼才义，徐建良.软件无线电原理与运用[M].北京：电子工业出版社，2001.11-14.
[2]韩实，沈保锁，王新乐.数字下变频器在现场可编程门阵列中实现[J].电子测量技术，2006(01).
[3]李建东，郭梯云，邬国扬.移动通信[M].西安:西安电子科技大学出版社，2006.237
[4]3GPP Ts05.02V7.7.0(Release1999). Multiplexing and multiple access on the radio path[s].
[5]孙孺石，丁怀元，穆万里，王泽权.GSM数字移动通信工程[M].北京：人民邮电出版社，1995.192-193.
[6]张威.GSM网络优化[M].中国移动通信公司，2003.178-179.
[7]3GPP TS05.01V8.9.0(Release1999).Physical layer on the radio path; General description [S].
[8]田斌，贴翊，任光亮译.无线通信[M].北京：电子工业出版社，2008.395.
[9] B. Sklar著.徐平平等译.数字通信——基础与应用[M].北京：电子工业出版社，2002.360.
[10]冯玉珉.通信系统原理[M].清华大学出版社，2006.
[11]李锋.GSM跳频数字直放站[D].厦门：厦门大学，2009.15-17.
[12]韩斌杰. GSM原理及其网络优化[M].北京：机械工业出版社，2005.
[13] A. Baier, et al,” Bit Synchronization and Timing Sensitivity in Adaptive Vitebri Equalizers ForNarrow-Band TDMA Mobile Radio Systems”[C].Vehicular Technology Conference. IEEE38th.1988.377-384.
[14]900/1800M TDMA数字蜂窝移动通信网——无线接口第二阶段物理层部分[S].
[15] GSM05.04version8.l(Release l999). Digital cellular telecommunications system; Modulation[S].
[16]田耘，徐文波，张延伟等编著.无线通信FPGA设计[M].北京：电子工业出版社，2008.275-276.
[17]张德丰等.MATLAB通信工程仿真[M].北京：机械工业出版社，2010.307.
[18]关雪梅，王晓东.快速傅里叶变换（FFT）与小波变换技术[J].牡丹江师范学院学报（自然科学版），2002(4)：19-20.
[19]张浩，钟子发，王红军.GSM公共信道中FCCH的同频分离与捕获[J]．通信对抗，2006(1)：36-38.
[20]刘继武.GSM空中信号截取与移动台定位技术研究[D].南京：东南大学，2004.
[21]夏玲.GSM/GPRS系统物理层算法仿真及基于ZSP核的优化实现[D].杭州：浙江大学，2006.23-24.
[22]王正生.GSM接收机同步技术研究与基于FPGA和DSP的接收机设计[D].北京：北京交通大学，2009.21.
[23]李子丰.连续相位调制研究及其解调算法的FPGA实现[D].西安：西安电子科技大学，2007.
[24]樊昌信，张甫翊，徐炳祥，吴成柯.通信原理[M].北京：国防工业出版社，2001.46-47.
[25]曹志刚，钱亚生.现代通信原理[M].北京：清华大学出版社，2008.262-264.
[26]张宇等.GSM网络演变为EDGE使用的8PSK调制[J].通讯世界，2006.
[27]Aria G D，Fast Adaptive Equalizers for Narrow Band TDMA Mobile Radio [J].IEEE.Trnas.Vehicular Tech,1991.vol.40(2):392-404.
[28]G Ungerboeck,” Adaptive Maximum-Likelihood Receiver for Carrier-Modulated DataTransmission Systems”[J],IEEE Trans. Commun. May1974.Vol.22(5):624-636.
[29]H. L. Van Trees, Detection，Estimation and Modulation Theory[J],Pt.I.NewYork,Wiley,1968.
[30]G. D. Fonrey,” Maximum-Likelihood Sequence Estimation of Digital Sequences in the Presence ofIntersymbol Interference”[J].IEEE Trans.Info.Theory,May1972.Vol.18(5):363-377.
[31]王新梅，肖国镇.纠错码—原理与方法[M].西安：电子科技大学出版社，2001.
[32]3GPP TS44.018V7.7.0(2006-12).Mobile radio interface layer3specification; Radio ResourceControl(RRC) protocol (Release7)[S].
[33]夏宇闻.数字系统设计—Verilog实现[M].北京：高等教育出版社，2006.16-18.
[34]罗杰，肖看，谭力等. Verilog HDL与数字ASIC设计基础[M].武汉：华中科技大学出版社，2008.
[35]梁成志.Lattice FPGA/CPLD设计[M].北京：人民邮电出版社，2011.10-13.
[36]杨小牛，楼才义，徐建良.软件无线电原理与运用[M].北京：电子工业出版社，2001.11-14.