直接序列扩频信号的检测与PN码参数估计的研究
摘要
直接序列扩频信号具有频带宽、信噪比低、低截获率和高抗干扰等特点,已经广泛用于军事通信、卫星通信、移动通信等领域。随着电子战与信息战的发展,对于直扩信号的侦查成为了通信领域的一个研究热点。
本文以BPSK调制的直扩信号为例,对低信噪比情况下的信号进行检测与PN码速率码周期估计。简要介绍了直接序列扩频通信系统的基本原理以及伪随机序列的基本知识。在载频检测方面运用了平方倍频检测法,给出了平方倍频法的算法推导与理论仿真,对于直扩信号的PN码速率采用了延时相乘法与循环谱法来检测,给出了算法推导与仿真结果,并分析了两种方法各自的优缺点。采用二次功率谱法和倒谱法对PN码周期进行估计,针对上述两种方法的缺点进行了改进,采用基于延时相关的二次功率谱法,很好地解决了关于长PN码周期的估计问题。在无码解扩方面做了部分工作,分析了本地截取信号的获取方法,并对原理做出了数学推导。
仿真结果表明,运用平方倍频法检测载频的信噪比检测门限是-22dB;对于延时相乘法和循环谱法检测PN码速率的信噪比检测门限分别是-20dB和-16dB;在对PN码周期进行估计时,二次功率谱法和倒谱法的信噪比检测门限分别为-14dB和-15dB,延时相关二次功率谱法虽然解决了长码周期估计的问题,但是相应的信噪比检测门限却上升为-12dB。
Direct sequence spread spectrum signal has wide bandwidth, low SNR, low interception rate and high anti-interference and so on .It has been widely used for military communications, satellite communications, mobile communications and other fields. With the electronic warfare and information warfare development, the DS signal detection has become a hot topic in the field of communications.
This paper takes DS BPSK modulated signals for example to research on detection of DS-SS signals and parameter estimation of PN sequence. It introduces a direct sequence spread spectrum communication system and the pseudo-random sequence of the basic principles of the basic knowledge. It uses the square harmonic detection method in the detection area of Carrier frequency. We derive an algorithm square multiplier method and the theoretical simulation. We use multiply delay and cyclic spectrum to detect the signal for the DS PN code rate, and show derivation and simulation results of the algorithm and analyzes their advantages and disadvantages of two methods. The paper adopts quadratic power spectrum and cepstrum method to estimate the PN code period, for the shortcomings of both methods has been improved, based on delay-related second power spectrum method provides a good solution on the long PN code period the estimation. Despreading without the code has done some work on the analysis of the local method of interception of the signal, and the mathematical theory is derived.
Simulation results show that the use of the square of carrier frequency harmonic noise ratio assay detection threshold is -22dB. For the delay with multiplication and cyclic spectrum, PN code detection rate of detection threshold SNR is -20dB and -16dB. In estimate of the PN code period, the second power spectrum and cepstrum SNR detection threshold is -14dB and -15dB. Delay related to the second power spectrum method has solved the estimate of the long code period, but the corresponding SNR detection threshold increases to -12dB.
本文以BPSK调制的直扩信号为例,对低信噪比情况下的信号进行检测与PN码速率码周期估计。简要介绍了直接序列扩频通信系统的基本原理以及伪随机序列的基本知识。在载频检测方面运用了平方倍频检测法,给出了平方倍频法的算法推导与理论仿真,对于直扩信号的PN码速率采用了延时相乘法与循环谱法来检测,给出了算法推导与仿真结果,并分析了两种方法各自的优缺点。采用二次功率谱法和倒谱法对PN码周期进行估计,针对上述两种方法的缺点进行了改进,采用基于延时相关的二次功率谱法,很好地解决了关于长PN码周期的估计问题。在无码解扩方面做了部分工作,分析了本地截取信号的获取方法,并对原理做出了数学推导。
仿真结果表明,运用平方倍频法检测载频的信噪比检测门限是-22dB;对于延时相乘法和循环谱法检测PN码速率的信噪比检测门限分别是-20dB和-16dB;在对PN码周期进行估计时,二次功率谱法和倒谱法的信噪比检测门限分别为-14dB和-15dB,延时相关二次功率谱法虽然解决了长码周期估计的问题,但是相应的信噪比检测门限却上升为-12dB。
Direct sequence spread spectrum signal has wide bandwidth, low SNR, low interception rate and high anti-interference and so on .It has been widely used for military communications, satellite communications, mobile communications and other fields. With the electronic warfare and information warfare development, the DS signal detection has become a hot topic in the field of communications.
This paper takes DS BPSK modulated signals for example to research on detection of DS-SS signals and parameter estimation of PN sequence. It introduces a direct sequence spread spectrum communication system and the pseudo-random sequence of the basic principles of the basic knowledge. It uses the square harmonic detection method in the detection area of Carrier frequency. We derive an algorithm square multiplier method and the theoretical simulation. We use multiply delay and cyclic spectrum to detect the signal for the DS PN code rate, and show derivation and simulation results of the algorithm and analyzes their advantages and disadvantages of two methods. The paper adopts quadratic power spectrum and cepstrum method to estimate the PN code period, for the shortcomings of both methods has been improved, based on delay-related second power spectrum method provides a good solution on the long PN code period the estimation. Despreading without the code has done some work on the analysis of the local method of interception of the signal, and the mathematical theory is derived.
Simulation results show that the use of the square of carrier frequency harmonic noise ratio assay detection threshold is -22dB. For the delay with multiplication and cyclic spectrum, PN code detection rate of detection threshold SNR is -20dB and -16dB. In estimate of the PN code period, the second power spectrum and cepstrum SNR detection threshold is -14dB and -15dB. Delay related to the second power spectrum method has solved the estimate of the long code period, but the corresponding SNR detection threshold increases to -12dB.
引文
1 H.Urkowitz. Energy Detection of Unknown Deterministic Signal. Proc IEEE. 1967,55:523~531
2 R.A. Dillard. Detectability of Spread Spectrum Signal. IEEE Trans on Aerosp Electron Sys. 1979,15:526~537
3 J.F.Kuehls, E.Geraniotis.Presence. Detection of Binary-Phase-Shift-Keyedand Direct-Sequence Spread-Spectrum Signals Using a Prefilter-Delay-and-Multiply Device. IEEE journal on SAIC, 1990,8(5):915~933
4张天骐,周正中.低信噪比直扩信号伪码周期检测的谱方法.仪器仪表学报. 2001,22(3):43~45
5张天骐,周正中.直扩信号伪码周期的谱检测.电波科学学报.2001, 16(4):518~521
6杨忠,张建立.低信噪比直扩信号的周期特征检测与参数估计.无线电工程. 1995,25(6):14~20
7冯富强,陈鹏举.低信噪比条件下DS信号的检测和参数估计.通信学报. 2002,23(9):63~68
8 C.M.Spooner, W.A.Gardner. Robust Feature Detection for Signal Interception. IEEE Trans. On Communications, 1994,42(5):2165~2173
9 C.M.Spooner, W.A.Gardner. Exploitation of Higher-Order Cyclostationarity for Weak-Signal Detection and Time-Delay Estimation. IEEE Digital Object Identifier. 1992,10:197~201
10 Lu Mingquan, Xiao Xianci. Detection of DS/SS Signal Using Fourth-Order Spectrum. Proceeding of ICSP’93:145~148
11 E.R.Adams, P.C.J.Hill. Detection of Direct Sequence Spread Spectrum Signals Using Higher-Order Statistical Processing. IEEE ICASSP-97.1997,5:21~24
12 E.R.Adams, M.Gouda, P.C.J.Hill. Detection the Characteristic of DS/SS Signals Using Higher-Order Correlation. IEEE, 1996,1:27~31
13沈振惠,唐斌.基于四阶统计2-D切片的直扩信号多参数估计.信号处理. 2005,21(3):304~306
14 A.Polydoros, J.K.Holmes. Autocorrelation Techniques for Wideband Detection of FH/DS Waveform in Random Tone Interference. MILCOM’83:215~219
15 A.Polydoros, C.L.Weber. Detection Performance Considerations for Direct-Sequence and Time-Hopping LPI Waveforms. IEEE Journal on SAIC,1985, 3(5):727~744
16 A.Polydoros, K.T.Woo. LPI Detection of Frequency-Hopping Signals Using Autocorrelation Techniques. IEEE Journal on SAIC,1985,3(5):714~726
17张建立.直扩信号的检测.无线电工程.1994,24(2):19~21
18何哲平,肖先赐.BPSK信号检测的小波相关法.信号处理,1999,15 (4):81~84
19杨超斌,邱玲,朱近康.一种直扩通信信号快速检测识别方法.电子学报.1999,27(7):89~91
20游凌.DS直扩信号参数隐周期特征分析法.信号处理.2000,16(4):8~14
21 G.Burel. Detection of Spread Spectrum Transmissions Using Fluctuations of Correlation Estimators, IEEE-ISPACS, 2000:B8.2.5.1～B8.2.5.6
22 G.Burel. Detection of Direct Sequence Spread Spectrum Transmissions without Prior Knowledge. IEEE, GLOBECOM’01.2001(1):236~239
23刘杰.直接序列扩频通信无码解扩的研究.华北电力大学硕士学位论文.2001:10~12
24詹亚锋,曹志刚,马正新.直接扩频序列信号的参数计. 2004,26(9):1176~ 1178
25王剑,贾坤.直扩信号检测与估计的改进.电讯技术.2004(1):44~47
26 Grace Xingxin Gao, David De Lorenzo, Alan Chen, Sherman Lo, Dennis Akos, Todd Walter,Per Enge.Galileo GIOVE-A Broadcast E5 Codes and their Application to Acquisition and Tracking, ION National Technical Meeting 2007, San Diego, California, 2007.
27 Grace Xingxin Gao, Alan Chen,Sherman Lo, David De Lorenzo, Per Enge. GNSS over China: the Compass MEO Satellite Codes. Inside GNSS Magazine. July-August, 2007:36~43
28 Grace Xingxin Gao, Dennis Akos, Todd Walter , Per Enge. GIOVE-B on the Air: Understanding Galileo’s New Signals. Inside GNSS Magazine. May-June, 2008:34~37
29 Grace Xingxin Gao, Alan Chen, Sherman Lo, David De Lorenzo, Per Enge. Compass-M1 Broadcast Codes in E2, E5b and E6 Frequency Bands. IEEE Journal of Selected Topics in Signal Processing. Special Issue on Advanced Signal Processing for GNSS and Robust Navigation. accepted May 2009
30安金坤,田斌,孙永军,易克初,于全.一种基于ITD算法的直扩信号检测算法.电子与信息学报.2010,32(5):1178~1182
31朱近康.扩频通信的频谱相关检测方法.通信学报.1998,19(12):9~14
32 G.Burel, C.Bouder. Blind Estimation of the Pseudo-Random Sequence of a Direct Sequence Spread Spectrum Signal. IEEE-MILCOM’2000, (10):22~25
33柯宏发,李玮.扩频信号的自回归滑动平均谱估计识别技术研究.现代电子技术.2002,4(7):49~51
34 Xiong Gang, Lii Ming, Tang bin. Direct Sequence Spread Spectrum Signal Detection Based on Chaos Theory. Communication, Circuits and Systems. 2007, ICCCAS 2007:727~730
35一种DS/SS信号PN码序列估计的神经网络方法.信号处理.2001,17(6): 533~537
36田日才.扩频通信.清华大学出版社.2007:1~74
37罗军辉,姬红兵,海锦霞.一种改进的扩频BPSK信号载频检测估计方法.电子信息对抗技术.2008,23(1),1~4
38闵宏飞,韩振铎.MPSK信号调制方式识别研究.微计算机信息.2007 10(3):161~162
39 Chin-Liang Wang, Kuo-Ming Wu.A New Narrowband Interference Suppression Scheme Spread-Spectrum CDMA Communications.IEEE Transactions on Signal Processing,2001,49:2832~2838
40 Suwon Kang, Yong-Hwan Lee. Rapid Acquisition of PN Signals for DS/SS Systems Using A Phase Estimator. IEEE Journal on Selected Areas in Communications, 2001,19:1128~1137
41董占奇,于宏毅,胡捍英.直扩信号扩频伪随机序列盲估计分析.无线电工程.2005,35(10):1~2
42徐海源,王丰华,黄知涛,周一宇.长码直扩信号的符号速率盲估计方法.2007,29(6):44~48
43邬佳,赵知劲,尚俊娜,孔宪正.低信噪比下的直扩信号检测和多参数估计方法.计算机仿真.2008,25(2):153~156
44 S.Ghavami, H.Alikhanian, B.Abolhassani, H.S.Rad. Blind multiuser dada estimation in asynchronous and unequal power DS-SS systems without any prior knowledge of spreading sequences, Sarnoff Symposium, 2009.SARNOFF’09.IEEE: 1~6
45董战奇,胡捍英,于宏毅.基于延时相乘-相关及谱分析的直扩信号检测与符号周期、码片时宽估计分析.2008,30(4):840~842
46 Pei-Yuan Peng, An Efficient Multi-User Detection Algorithm for Direct Sequence Code Division Multiple Access by Using Neural Networks. IEEEInternational Conference on Communications. 2001,1:36~40
47 Jun Wang, E.Geraniotis. Narrow Band Interference Suppression in Spread Spectrum Communication with Iterative Decoding. IEEE Sixth International Symposium on Spread Spectrum Techniques and Applications, 2000,1:98~101
48金艳,姬红兵.基于循环自相关的PSK信号盲参数估计新方法.西安电子科技大学学报.2006,33(6):892~895
49金艳,姬红兵,罗军辉.一种基于循环统计量的直扩信号检测与参数估计方法.电子学报.2006,34(4),634~637
50 D.J.Torrieri. Performance of Direct Sequence Systems with Long Pseudo-Noise Sequences. IEEE Selected Areas in Communications, 1992,10: 770~781
51赵知劲,邬佳,徐春云.基于四阶累计量的DSSS/QPSK信号检测方法研究.电子学报,2007,35(6):1046~1049
52 C.A.French, W.A.Gardner. Spread Spectrum Despreading without the Code. IEEE, 1986,34(4):404~407
53 Pu Miao, Tianqi Zhang, Wei zhang, Guoming Ma, Yanli Liu. Period Estimation of the PN Sequence for Direct Sequence Spread Spectrum in Multipath Environment. Wireless Communication, Networking and Mobile Computing, 2009. Wicom’09. 5th International conference. 2009: 1~4
54张天骐,李雪松,代少升.一种同时估计直扩信号伪码周期及码片速率的方法.舰船电子对抗.2008,31(3):77~83
55 Hengdong Wei, Liping Li. An Efficient Methed for Detecting Chaotic Spread Spectrum Sequences. Computer Modeling and Simulation. 2010. ICCMS’10. Second International conference 2010, 244~248
2 R.A. Dillard. Detectability of Spread Spectrum Signal. IEEE Trans on Aerosp Electron Sys. 1979,15:526~537
3 J.F.Kuehls, E.Geraniotis.Presence. Detection of Binary-Phase-Shift-Keyedand Direct-Sequence Spread-Spectrum Signals Using a Prefilter-Delay-and-Multiply Device. IEEE journal on SAIC, 1990,8(5):915~933
4张天骐,周正中.低信噪比直扩信号伪码周期检测的谱方法.仪器仪表学报. 2001,22(3):43~45
5张天骐,周正中.直扩信号伪码周期的谱检测.电波科学学报.2001, 16(4):518~521
6杨忠,张建立.低信噪比直扩信号的周期特征检测与参数估计.无线电工程. 1995,25(6):14~20
7冯富强,陈鹏举.低信噪比条件下DS信号的检测和参数估计.通信学报. 2002,23(9):63~68
8 C.M.Spooner, W.A.Gardner. Robust Feature Detection for Signal Interception. IEEE Trans. On Communications, 1994,42(5):2165~2173
9 C.M.Spooner, W.A.Gardner. Exploitation of Higher-Order Cyclostationarity for Weak-Signal Detection and Time-Delay Estimation. IEEE Digital Object Identifier. 1992,10:197~201
10 Lu Mingquan, Xiao Xianci. Detection of DS/SS Signal Using Fourth-Order Spectrum. Proceeding of ICSP’93:145~148
11 E.R.Adams, P.C.J.Hill. Detection of Direct Sequence Spread Spectrum Signals Using Higher-Order Statistical Processing. IEEE ICASSP-97.1997,5:21~24
12 E.R.Adams, M.Gouda, P.C.J.Hill. Detection the Characteristic of DS/SS Signals Using Higher-Order Correlation. IEEE, 1996,1:27~31
13沈振惠,唐斌.基于四阶统计2-D切片的直扩信号多参数估计.信号处理. 2005,21(3):304~306
14 A.Polydoros, J.K.Holmes. Autocorrelation Techniques for Wideband Detection of FH/DS Waveform in Random Tone Interference. MILCOM’83:215~219
15 A.Polydoros, C.L.Weber. Detection Performance Considerations for Direct-Sequence and Time-Hopping LPI Waveforms. IEEE Journal on SAIC,1985, 3(5):727~744
16 A.Polydoros, K.T.Woo. LPI Detection of Frequency-Hopping Signals Using Autocorrelation Techniques. IEEE Journal on SAIC,1985,3(5):714~726
17张建立.直扩信号的检测.无线电工程.1994,24(2):19~21
18何哲平,肖先赐.BPSK信号检测的小波相关法.信号处理,1999,15 (4):81~84
19杨超斌,邱玲,朱近康.一种直扩通信信号快速检测识别方法.电子学报.1999,27(7):89~91
20游凌.DS直扩信号参数隐周期特征分析法.信号处理.2000,16(4):8~14
21 G.Burel. Detection of Spread Spectrum Transmissions Using Fluctuations of Correlation Estimators, IEEE-ISPACS, 2000:B8.2.5.1～B8.2.5.6
22 G.Burel. Detection of Direct Sequence Spread Spectrum Transmissions without Prior Knowledge. IEEE, GLOBECOM’01.2001(1):236~239
23刘杰.直接序列扩频通信无码解扩的研究.华北电力大学硕士学位论文.2001:10~12
24詹亚锋,曹志刚,马正新.直接扩频序列信号的参数计. 2004,26(9):1176~ 1178
25王剑,贾坤.直扩信号检测与估计的改进.电讯技术.2004(1):44~47
26 Grace Xingxin Gao, David De Lorenzo, Alan Chen, Sherman Lo, Dennis Akos, Todd Walter,Per Enge.Galileo GIOVE-A Broadcast E5 Codes and their Application to Acquisition and Tracking, ION National Technical Meeting 2007, San Diego, California, 2007.
27 Grace Xingxin Gao, Alan Chen,Sherman Lo, David De Lorenzo, Per Enge. GNSS over China: the Compass MEO Satellite Codes. Inside GNSS Magazine. July-August, 2007:36~43
28 Grace Xingxin Gao, Dennis Akos, Todd Walter , Per Enge. GIOVE-B on the Air: Understanding Galileo’s New Signals. Inside GNSS Magazine. May-June, 2008:34~37
29 Grace Xingxin Gao, Alan Chen, Sherman Lo, David De Lorenzo, Per Enge. Compass-M1 Broadcast Codes in E2, E5b and E6 Frequency Bands. IEEE Journal of Selected Topics in Signal Processing. Special Issue on Advanced Signal Processing for GNSS and Robust Navigation. accepted May 2009
30安金坤,田斌,孙永军,易克初,于全.一种基于ITD算法的直扩信号检测算法.电子与信息学报.2010,32(5):1178~1182
31朱近康.扩频通信的频谱相关检测方法.通信学报.1998,19(12):9~14
32 G.Burel, C.Bouder. Blind Estimation of the Pseudo-Random Sequence of a Direct Sequence Spread Spectrum Signal. IEEE-MILCOM’2000, (10):22~25
33柯宏发,李玮.扩频信号的自回归滑动平均谱估计识别技术研究.现代电子技术.2002,4(7):49~51
34 Xiong Gang, Lii Ming, Tang bin. Direct Sequence Spread Spectrum Signal Detection Based on Chaos Theory. Communication, Circuits and Systems. 2007, ICCCAS 2007:727~730
35一种DS/SS信号PN码序列估计的神经网络方法.信号处理.2001,17(6): 533~537
36田日才.扩频通信.清华大学出版社.2007:1~74
37罗军辉,姬红兵,海锦霞.一种改进的扩频BPSK信号载频检测估计方法.电子信息对抗技术.2008,23(1),1~4
38闵宏飞,韩振铎.MPSK信号调制方式识别研究.微计算机信息.2007 10(3):161~162
39 Chin-Liang Wang, Kuo-Ming Wu.A New Narrowband Interference Suppression Scheme Spread-Spectrum CDMA Communications.IEEE Transactions on Signal Processing,2001,49:2832~2838
40 Suwon Kang, Yong-Hwan Lee. Rapid Acquisition of PN Signals for DS/SS Systems Using A Phase Estimator. IEEE Journal on Selected Areas in Communications, 2001,19:1128~1137
41董占奇,于宏毅,胡捍英.直扩信号扩频伪随机序列盲估计分析.无线电工程.2005,35(10):1~2
42徐海源,王丰华,黄知涛,周一宇.长码直扩信号的符号速率盲估计方法.2007,29(6):44~48
43邬佳,赵知劲,尚俊娜,孔宪正.低信噪比下的直扩信号检测和多参数估计方法.计算机仿真.2008,25(2):153~156
44 S.Ghavami, H.Alikhanian, B.Abolhassani, H.S.Rad. Blind multiuser dada estimation in asynchronous and unequal power DS-SS systems without any prior knowledge of spreading sequences, Sarnoff Symposium, 2009.SARNOFF’09.IEEE: 1~6
45董战奇,胡捍英,于宏毅.基于延时相乘-相关及谱分析的直扩信号检测与符号周期、码片时宽估计分析.2008,30(4):840~842
46 Pei-Yuan Peng, An Efficient Multi-User Detection Algorithm for Direct Sequence Code Division Multiple Access by Using Neural Networks. IEEEInternational Conference on Communications. 2001,1:36~40
47 Jun Wang, E.Geraniotis. Narrow Band Interference Suppression in Spread Spectrum Communication with Iterative Decoding. IEEE Sixth International Symposium on Spread Spectrum Techniques and Applications, 2000,1:98~101
48金艳,姬红兵.基于循环自相关的PSK信号盲参数估计新方法.西安电子科技大学学报.2006,33(6):892~895
49金艳,姬红兵,罗军辉.一种基于循环统计量的直扩信号检测与参数估计方法.电子学报.2006,34(4),634~637
50 D.J.Torrieri. Performance of Direct Sequence Systems with Long Pseudo-Noise Sequences. IEEE Selected Areas in Communications, 1992,10: 770~781
51赵知劲,邬佳,徐春云.基于四阶累计量的DSSS/QPSK信号检测方法研究.电子学报,2007,35(6):1046~1049
52 C.A.French, W.A.Gardner. Spread Spectrum Despreading without the Code. IEEE, 1986,34(4):404~407
53 Pu Miao, Tianqi Zhang, Wei zhang, Guoming Ma, Yanli Liu. Period Estimation of the PN Sequence for Direct Sequence Spread Spectrum in Multipath Environment. Wireless Communication, Networking and Mobile Computing, 2009. Wicom’09. 5th International conference. 2009: 1~4
54张天骐,李雪松,代少升.一种同时估计直扩信号伪码周期及码片速率的方法.舰船电子对抗.2008,31(3):77~83
55 Hengdong Wei, Liping Li. An Efficient Methed for Detecting Chaotic Spread Spectrum Sequences. Computer Modeling and Simulation. 2010. ICCMS’10. Second International conference 2010, 244~248