基于FPGA的软件无线电多模式调制解调的研究与实现
摘要
软件无线电在无线通信领域被称为是自模拟通信过渡到数字通信之后的又一次革命,在军用和民用方面都有着广泛的应用。它是一种新的无线通信技术,基于通用的可编程硬件平台,把尽可能多的通信功能用软件实现,从而使系统的改进和升级都非常方便,容易实现不同通信系统之间的兼容。
软件无线电的基本思想是构造一个具有开放性、标准化、模块化的通用硬件平台,从而使软件无线电中的调制方式产生多模式化。而多模式调制的存在,就要有自动的多模式调制的识别方法。所以,多模式调制方式的自动识别是软件无线电中必须具备的功能。如何将多模式调制的识别方法与软件无线电的解调方法相结合,同时实现信号的接收和解调,是实现软件无线电的关键技术之一,具有重要的应用前景。
而在数字通信系统中,全数字接收机已经得到了广泛的应用。如何利用数字化方法设计通信系统中的调制解调技术是实际应用中的一项重要技术。GMSK最小高斯频移键控是一种典型的连续相位调制方式,具有包络恒定、频谱紧凑、抗干扰能力强等特点,在移动通信等场合得到了广泛应用。在GMSK调制解调的实现中采用了FPGA可编程逻辑器件,不仅克服了模拟系统灵活性不好的缺点,而且易于系统的修改和升级。
针对上述情况,论文的主要研究工作有:
1、介绍了软件无线电的三种结构形式,针对目前的设计条件,指出宽带中频带通采样软件无线电结构是目前较为理想的结构形式。
2、对调制模式识别中基本特征参数频率、包络以及相位的提取方法进行了分析,并在此基础上对三种调制信号分类方法分别进行了讨论。在信道条件较好的情况下,提出利用参量直方图的方法对三种基本特征参数分别进行统计,根据峰值的数目从而可以来区分ASK、PSK和FSK信号。当信道条件一般时,文中以决策论为依据,使用4个特征参数实现了二进制和四进制ASK、FSK、PSK的分类。
3、采用高阶统计量的方式对低信噪比条件下的调制信号进行识别,利用计算出的几个高阶累积量,提取特征参数,成功地实现了低信噪比条件下ASK、PSK和FSK的二制和四进制信号的分类。
4、最后在Mat1ab中进行对软件无线电中的GMSK调制与解调的仿真,并且在FPGA上实现其调制与解调。
Software radio in the wireless communications known as the transition from analog communication to digital commucation again after revolution in military and civilian aspects have a wide range of application.It is a new wireless communication technology.Programmable hardware based on a common platform,the communication function as much as possible with software,making system improvements and upgrades are very convenient and easy to achieve compatibility between different communication systems.
The basic idea of Software Radio is to construct a general hardware platformwith openness,standardization and modularization.The generalization of SR must bringthe multi-modularization,so the automatic multi-mode modulation recognition methodcomes into necessity to ensure correct demodulation.As a result,the automaticmodulation recognition is one of the necessary functions.How to make the method ofautomatic modulation recognition adaptive to thedemodulation method and realize theautomatic reception and demodulation is one of the key technologies and must have a wide application.
In digital communication systems,all-digital receivers become more popular.It hasbecome an important technology that realizes the modulator and demodulator of communication system in digitalization method.GMSK Minimum Gaussian frequency shiftkeying is a typical continuous phase modulation method,which has the characteristics of constant envelope,compact spectrum,and anti-jamming performance.GMSK can effectively reduce inter-channel interference,improve the efficiency of non-linear power amplifier,and has been widely used in mobile system and others systems.In the GMSK modem used in the FPGA implementation of programmable logic devices,analog system flexibility not only to overcome the shortcomings of bad,and easy system modifications and upgrades.
In allusion to the status mentioned above,the contents finished in the dissertationare listed as follows:
1 The three Software Radio architectures were introduced and the wideband and band-passsample architecture was proved as the practical one now in the present design condition.
2 The extraction method of character parameter including envelope,frequency and phase was analyzed and three classification method of digital modulationwere also discussed.When channel condition is good,the parameter histogramdistribution method was introduced to make a statistics of the three basic characterparameters.
According to the peak number,the 2ASK,4ASK,2PSK,4PSK,2FSK and 4FSK can be classified well.In the channel condition that is not so good,the decisiontheory method was adopted to extract four character parameters so that the classificationof 2ASK,4ASK,2PSK,4PSK,2FSK and 4FSK was realized.
3 The recognition of modulation signals under the low SNR condition is alwaysthe important research content of signal recognition.In the dissertation,the high ordercumulants method was adopted to realize successfully the classification of 2ASK,4ASK,2PSK,4PSK,2FSK and 4FSK by extracting four character parameters based onseveral high order cumulants calculated.
4 Finally Matlab carried out on software radio GMSK modulation and demodulation of the simulation,and FPGA to achieve the modulation and demodulation.
软件无线电的基本思想是构造一个具有开放性、标准化、模块化的通用硬件平台,从而使软件无线电中的调制方式产生多模式化。而多模式调制的存在,就要有自动的多模式调制的识别方法。所以,多模式调制方式的自动识别是软件无线电中必须具备的功能。如何将多模式调制的识别方法与软件无线电的解调方法相结合,同时实现信号的接收和解调,是实现软件无线电的关键技术之一,具有重要的应用前景。
而在数字通信系统中,全数字接收机已经得到了广泛的应用。如何利用数字化方法设计通信系统中的调制解调技术是实际应用中的一项重要技术。GMSK最小高斯频移键控是一种典型的连续相位调制方式,具有包络恒定、频谱紧凑、抗干扰能力强等特点,在移动通信等场合得到了广泛应用。在GMSK调制解调的实现中采用了FPGA可编程逻辑器件,不仅克服了模拟系统灵活性不好的缺点,而且易于系统的修改和升级。
针对上述情况,论文的主要研究工作有:
1、介绍了软件无线电的三种结构形式,针对目前的设计条件,指出宽带中频带通采样软件无线电结构是目前较为理想的结构形式。
2、对调制模式识别中基本特征参数频率、包络以及相位的提取方法进行了分析,并在此基础上对三种调制信号分类方法分别进行了讨论。在信道条件较好的情况下,提出利用参量直方图的方法对三种基本特征参数分别进行统计,根据峰值的数目从而可以来区分ASK、PSK和FSK信号。当信道条件一般时,文中以决策论为依据,使用4个特征参数实现了二进制和四进制ASK、FSK、PSK的分类。
3、采用高阶统计量的方式对低信噪比条件下的调制信号进行识别,利用计算出的几个高阶累积量,提取特征参数,成功地实现了低信噪比条件下ASK、PSK和FSK的二制和四进制信号的分类。
4、最后在Mat1ab中进行对软件无线电中的GMSK调制与解调的仿真,并且在FPGA上实现其调制与解调。
Software radio in the wireless communications known as the transition from analog communication to digital commucation again after revolution in military and civilian aspects have a wide range of application.It is a new wireless communication technology.Programmable hardware based on a common platform,the communication function as much as possible with software,making system improvements and upgrades are very convenient and easy to achieve compatibility between different communication systems.
The basic idea of Software Radio is to construct a general hardware platformwith openness,standardization and modularization.The generalization of SR must bringthe multi-modularization,so the automatic multi-mode modulation recognition methodcomes into necessity to ensure correct demodulation.As a result,the automaticmodulation recognition is one of the necessary functions.How to make the method ofautomatic modulation recognition adaptive to thedemodulation method and realize theautomatic reception and demodulation is one of the key technologies and must have a wide application.
In digital communication systems,all-digital receivers become more popular.It hasbecome an important technology that realizes the modulator and demodulator of communication system in digitalization method.GMSK Minimum Gaussian frequency shiftkeying is a typical continuous phase modulation method,which has the characteristics of constant envelope,compact spectrum,and anti-jamming performance.GMSK can effectively reduce inter-channel interference,improve the efficiency of non-linear power amplifier,and has been widely used in mobile system and others systems.In the GMSK modem used in the FPGA implementation of programmable logic devices,analog system flexibility not only to overcome the shortcomings of bad,and easy system modifications and upgrades.
In allusion to the status mentioned above,the contents finished in the dissertationare listed as follows:
1 The three Software Radio architectures were introduced and the wideband and band-passsample architecture was proved as the practical one now in the present design condition.
2 The extraction method of character parameter including envelope,frequency and phase was analyzed and three classification method of digital modulationwere also discussed.When channel condition is good,the parameter histogramdistribution method was introduced to make a statistics of the three basic characterparameters.
According to the peak number,the 2ASK,4ASK,2PSK,4PSK,2FSK and 4FSK can be classified well.In the channel condition that is not so good,the decisiontheory method was adopted to extract four character parameters so that the classificationof 2ASK,4ASK,2PSK,4PSK,2FSK and 4FSK was realized.
3 The recognition of modulation signals under the low SNR condition is alwaysthe important research content of signal recognition.In the dissertation,the high ordercumulants method was adopted to realize successfully the classification of 2ASK,4ASK,2PSK,4PSK,2FSK and 4FSK by extracting four character parameters based onseveral high order cumulants calculated.
4 Finally Matlab carried out on software radio GMSK modulation and demodulation of the simulation,and FPGA to achieve the modulation and demodulation.
引文
[1].杨小牛,楼才义等.软件无线电原理与应用[M].北京:电子工业出版社,2001.
[2].肖为民,许希武.软件无线电综述[J].电子学报.1998,26(2):65-70.
[3]. K.C.Ho,W.Prokopiw and Y.T.Chan.Modulation identification by the wavelets in Proc,SPIE,Sangwoo Cho,Chong Hyun Lee,Jooh wan chum.Classification of digital modulations using the LPC.National Aerospace and Electronics Conference,Proceedings of the IEEE,2000, 774-778.
[4]. Mitiola J.The Software radio architecture.IEEE Communication Magzine,1995(5).
[5]. Polydoros A,Kim K.On the detection and classification of quadrature digital modulations in broad-band noise.IEEE Trans.Communications,1990,38:1199-1211.
[6].韩国栋,蔡斌,邬江兴,调制分析与识别的谱相关方法[J],系统工程与电子技术.2001,Vol. 23,No.3:34-36.
[7]. Samir S.Soliman,Shue-Zen Hsue.Signal classification using statistical moments,IEEE Trans. Communication,1992,vo1.40:908-916.
[8]. Wei Dai,Wouzheng Wang,Jing Wang,Joint Power Estimation and Modulation Classification Using Second-and Higher Statistics.Wireless Communications and networking Conference, 2002,IEEE,Vol.1:155-158.
[9].苗建苏,傅丰林.RBF网络在通信信号自动识别中的应用[J].西安电子科技大学学报. 1996,23:34-36.
[10].王磊,陈鹏举,程乾,修正平均周期图法在通信信号分选识别中的应用[J].电讯技术. 2002,(4):30-33.
[11].冯晋利,武洁,王绍卿.快速高分辨率估计算法[J].现代通信.1998,(1).
[12].丘天爽,张旭秀,李小兵,孙永梅.统计信号处理——非高斯信号处理及其应用[M].北京:电子工业出版社,2004.
[13].庄婵飞,赵知劲.模拟调制信号的神经网络识别方法[J].杭州电子工业学院学报. 2002,22(3):34-36.
[14]. H Hadinejad-Mahram,A O Hero III,Robust QAM Modulation Classification Via Moment Matrices[A].PIMRC 2000[C].2000,1:133-137.
[15]. E E Azzouz,A K Nandi.Automatic identification of digital modulation types[J].Signal Processing,1995,47:55-69.
[16].冷爱国.软件无线电技术的调制解调算法研究.电子科技大学.电路与系统.硕士学位论文,2005
[17].王福昌,熊兆飞,黄本熊.通信原理[M].清华大学出版社,2006.3.
[18].樊昌信等.通信原理(第二版)[M],国防工业出版社,2001.
[19].肖妍妍.GMSK、SPSK调制算法研究及ASIC实现.电子科技大学.电路与系统.硕士学位论文,2002.3.
[20].吴迪.GMSK解调理论的研究和无线调制解调器的设计.东北大学:控制理论与控制工程系.硕士学位论文,2001.6.1
[21].侯伯亨,顾新.VHDL硬件描述语言与数字逻辑电路设计[M].西安电子科技大学出版社,2000.4.
[22].李国纲.软件无线电中几种调制解调算法的研究.浙江大学:通信与信息系统系.硕士学位论文,2003.2.1.
[23].仇佩亮,陈惠芳,谢磊著.数字通信基础[M].电子工业出版社,2007年.
[24].唐金花.GMSK调制的数字化实现[J].金华职业技术学院学报,Vo1.6 Vo.7 2006.9.
[25].娄莉.GMSK数字调制的仿真与分析[J].现代电子技术,1994.1,Vol.12(No.4),PP.11-13.
[26].刘敏.基于软件无线电的pi/4-QPSK与GMSK调制系统实现.南京航空航天大学:通信与信息系统.硕士学位论文,2004.1.
[27].王士林,陆存乐,现代数字调制技术[M].北京:人民邮电出版社,1987.
[28]. Y.C.Wu and T.S.Ng,“New implementation of a GMSK demodulator in linear software radio receiver”in Proc.IEEE PIMRC 2000,Sep.2000,pp.1049-1053.
[29].王立宁.MATLAB与通信仿真[M].人民邮电出版社,2000.1.
[30]. Minjian zhao,Mengtao yuan,Student Member.IEEE etc.A Nocoherent GMSK Receiver for Software Radio,2002.
[31].马彧等.CPLD/FPGA可编程逻辑器件实用教程[M].机械工业出版社,2006.6.
[32].蔡涛,宋俊德,王海.基于软件无线电技术的第三代移动通信系统结构,www.cetinet.cn.
[33].梁兵.适用于数字蜂窝移动通信系统的几种数字调制技术[J].微波与卫星通信,1994.1.
[34].李丽,王振领.MATLAB工程计算及应用[M].人民邮电出版社,2004.7.
[35].刘琦.无线接收机中的扩频序列同步的数字化实现.哈尔滨工程大学:通信与信息系统.硕士学位论文,2002.6.
[36].袁梦涛.软件无线电中的数字信号处理及参数估计.浙江大学:信息与通信系统系.硕士学位论文,2002.1.1
[37].雷霞.软件无线电算法研究—前向结构解调算法.电子科技大学:硕士学位论文,1999.12.1.
[38].谢印庆.软件无线电中GMSK与QPSK调制解调及其TMS320C6711 DSP实现的研究.太原理工大学.信号与信息处理.硕士学位论文,2006.4.
[39]. Tarokh,V,Jafarkhani,H,A differential detection scheme for transmit diversity,Selected Areas in Communications,IEEE Journal on Communications,Volume:18,Issue.
[2].肖为民,许希武.软件无线电综述[J].电子学报.1998,26(2):65-70.
[3]. K.C.Ho,W.Prokopiw and Y.T.Chan.Modulation identification by the wavelets in Proc,SPIE,Sangwoo Cho,Chong Hyun Lee,Jooh wan chum.Classification of digital modulations using the LPC.National Aerospace and Electronics Conference,Proceedings of the IEEE,2000, 774-778.
[4]. Mitiola J.The Software radio architecture.IEEE Communication Magzine,1995(5).
[5]. Polydoros A,Kim K.On the detection and classification of quadrature digital modulations in broad-band noise.IEEE Trans.Communications,1990,38:1199-1211.
[6].韩国栋,蔡斌,邬江兴,调制分析与识别的谱相关方法[J],系统工程与电子技术.2001,Vol. 23,No.3:34-36.
[7]. Samir S.Soliman,Shue-Zen Hsue.Signal classification using statistical moments,IEEE Trans. Communication,1992,vo1.40:908-916.
[8]. Wei Dai,Wouzheng Wang,Jing Wang,Joint Power Estimation and Modulation Classification Using Second-and Higher Statistics.Wireless Communications and networking Conference, 2002,IEEE,Vol.1:155-158.
[9].苗建苏,傅丰林.RBF网络在通信信号自动识别中的应用[J].西安电子科技大学学报. 1996,23:34-36.
[10].王磊,陈鹏举,程乾,修正平均周期图法在通信信号分选识别中的应用[J].电讯技术. 2002,(4):30-33.
[11].冯晋利,武洁,王绍卿.快速高分辨率估计算法[J].现代通信.1998,(1).
[12].丘天爽,张旭秀,李小兵,孙永梅.统计信号处理——非高斯信号处理及其应用[M].北京:电子工业出版社,2004.
[13].庄婵飞,赵知劲.模拟调制信号的神经网络识别方法[J].杭州电子工业学院学报. 2002,22(3):34-36.
[14]. H Hadinejad-Mahram,A O Hero III,Robust QAM Modulation Classification Via Moment Matrices[A].PIMRC 2000[C].2000,1:133-137.
[15]. E E Azzouz,A K Nandi.Automatic identification of digital modulation types[J].Signal Processing,1995,47:55-69.
[16].冷爱国.软件无线电技术的调制解调算法研究.电子科技大学.电路与系统.硕士学位论文,2005
[17].王福昌,熊兆飞,黄本熊.通信原理[M].清华大学出版社,2006.3.
[18].樊昌信等.通信原理(第二版)[M],国防工业出版社,2001.
[19].肖妍妍.GMSK、SPSK调制算法研究及ASIC实现.电子科技大学.电路与系统.硕士学位论文,2002.3.
[20].吴迪.GMSK解调理论的研究和无线调制解调器的设计.东北大学:控制理论与控制工程系.硕士学位论文,2001.6.1
[21].侯伯亨,顾新.VHDL硬件描述语言与数字逻辑电路设计[M].西安电子科技大学出版社,2000.4.
[22].李国纲.软件无线电中几种调制解调算法的研究.浙江大学:通信与信息系统系.硕士学位论文,2003.2.1.
[23].仇佩亮,陈惠芳,谢磊著.数字通信基础[M].电子工业出版社,2007年.
[24].唐金花.GMSK调制的数字化实现[J].金华职业技术学院学报,Vo1.6 Vo.7 2006.9.
[25].娄莉.GMSK数字调制的仿真与分析[J].现代电子技术,1994.1,Vol.12(No.4),PP.11-13.
[26].刘敏.基于软件无线电的pi/4-QPSK与GMSK调制系统实现.南京航空航天大学:通信与信息系统.硕士学位论文,2004.1.
[27].王士林,陆存乐,现代数字调制技术[M].北京:人民邮电出版社,1987.
[28]. Y.C.Wu and T.S.Ng,“New implementation of a GMSK demodulator in linear software radio receiver”in Proc.IEEE PIMRC 2000,Sep.2000,pp.1049-1053.
[29].王立宁.MATLAB与通信仿真[M].人民邮电出版社,2000.1.
[30]. Minjian zhao,Mengtao yuan,Student Member.IEEE etc.A Nocoherent GMSK Receiver for Software Radio,2002.
[31].马彧等.CPLD/FPGA可编程逻辑器件实用教程[M].机械工业出版社,2006.6.
[32].蔡涛,宋俊德,王海.基于软件无线电技术的第三代移动通信系统结构,www.cetinet.cn.
[33].梁兵.适用于数字蜂窝移动通信系统的几种数字调制技术[J].微波与卫星通信,1994.1.
[34].李丽,王振领.MATLAB工程计算及应用[M].人民邮电出版社,2004.7.
[35].刘琦.无线接收机中的扩频序列同步的数字化实现.哈尔滨工程大学:通信与信息系统.硕士学位论文,2002.6.
[36].袁梦涛.软件无线电中的数字信号处理及参数估计.浙江大学:信息与通信系统系.硕士学位论文,2002.1.1
[37].雷霞.软件无线电算法研究—前向结构解调算法.电子科技大学:硕士学位论文,1999.12.1.
[38].谢印庆.软件无线电中GMSK与QPSK调制解调及其TMS320C6711 DSP实现的研究.太原理工大学.信号与信息处理.硕士学位论文,2006.4.
[39]. Tarokh,V,Jafarkhani,H,A differential detection scheme for transmit diversity,Selected Areas in Communications,IEEE Journal on Communications,Volume:18,Issue.