基于遗传退火算法的解相关多用户检测的研究
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摘要
码分多址(CDMA)通信系统以频谱利用率高、系统容量大、频率管理容易，软切换、移动台发射功率低、信道的传输速率高等优点代表了新一代移动通信，在未来的无线通信系统中必将扮演极为重要的角色。但是在实际的通信系统中地址码很难做到完全正交，以致于在用户数比较大时，存在不可避免的严重的多址干扰，极大地降低了通信服务地质量。要想真正消除干扰，大幅度提高系统的容量，就必需采用多用户检测技术。
本论文主要介绍扩频技术在通信中的运用，针对CDMA通信系统的特点，研究了现有的一些多用户检测技术，希望通过研究找到一种有效的CDMA通信的多用户检测的方法。同时还要考虑尽可能小的比特误码率(BER)。考虑到模拟退火算法和遗传算法各自的优缺点，将两者有效的结合起来，通过模拟退火算法来减轻遗传算法的选择压力，利用模拟退火算法的Boltzmann机制来接收交叉和变异后的个体，并且结合CDMA通信系统多用户检测的特点，采用了遗传退火算法对CDMA通信系统的多用户进行检测的研究。为了验证这一思想，我们进行了计算机仿真实验，并对仿真结果进行了分析，结果表明这种算法的应用使系统性能得到提高，优于传统的检测方法。实验结果表明了这一检测方法的有效性。
本文进行的主要工作如下：
1．对CDMA扩展频谱通信进行了系统的介绍，并详细介绍了CDMA的多用户检测方法，分析一些多用户检测算法的优缺点。
2．介绍了模拟退火算法和遗传算法，在分析两种算法的优缺点的基础上将两者有效的结合起来得到一种算法即遗传退火算法，并将遗传退火算法应用到频率分配中与遗传算法进行比较。
3．结合CDMA通信系统多用户检测的特点，采用遗传退火算法来进行CDMA的多用户检测。
Code division multiple access(CDMA) communications systems being possessed of the merits of great capacity and soft hand-off and so on must have taken a significant role in future wireless communications systems. Because PN sequences used in communications systems are been vertical completely , when numbers of user are more, there are multiple access interference(MAI) in CDMA and serving quality in communications systems is reduced. If interference are avoided and capacity of systems is increased, multi-user detection technology must be used in CDMA.
This paper introduces the application of the spread spectrum technology in communications. Aiming characteristic in CDMA communication systems, after we discuss some multi-user detection technology at present, and want to find a effective multi-user detection method with a small bit error rate in CDMA communication. Considering respective merits and disadvantages at simulated annealing algorithm and genetic algorithm, we combine them .By using simulated annealing algorithm(SA) to mitigate the stress of culling in genetic algorithm(GA) and utilizing the Boltzmann mechanism of simulated annealing algorithm to control the acceptance of the individuals generated by copulated and varied, a CDMA multi-user detection method based on genetic annealing algorithm is adopted. The computer simulative experiment is conducted. Satisfying result is got after analyze the simulation result. The result proved that the use of this algorithm will improve the performance of system and that the performance of system is better than the decorrelating multi-user detection. Experiments proved its efficiency.
The following is what I have done in this paper:
1.The paper systematically introduced the fundamental knowledge of Spread Spectrum Communication in CDMA , introduced multi-user detection technology in CDMA, and analysed advantages and flaws of multiuser detection technology.
2.The paper introduced SA and GA. Through the analysis of faults and merits of two algorithms,we combined Genetic Algorithm with Simulated Annealing Algorithm and formed a genetic annealing algorithm and applied to frequence assignment.
3.The paper used a multi-user detection based on genetic annealing algorithm.
本论文主要介绍扩频技术在通信中的运用，针对CDMA通信系统的特点，研究了现有的一些多用户检测技术，希望通过研究找到一种有效的CDMA通信的多用户检测的方法。同时还要考虑尽可能小的比特误码率(BER)。考虑到模拟退火算法和遗传算法各自的优缺点，将两者有效的结合起来，通过模拟退火算法来减轻遗传算法的选择压力，利用模拟退火算法的Boltzmann机制来接收交叉和变异后的个体，并且结合CDMA通信系统多用户检测的特点，采用了遗传退火算法对CDMA通信系统的多用户进行检测的研究。为了验证这一思想，我们进行了计算机仿真实验，并对仿真结果进行了分析，结果表明这种算法的应用使系统性能得到提高，优于传统的检测方法。实验结果表明了这一检测方法的有效性。
本文进行的主要工作如下：
1．对CDMA扩展频谱通信进行了系统的介绍，并详细介绍了CDMA的多用户检测方法，分析一些多用户检测算法的优缺点。
2．介绍了模拟退火算法和遗传算法，在分析两种算法的优缺点的基础上将两者有效的结合起来得到一种算法即遗传退火算法，并将遗传退火算法应用到频率分配中与遗传算法进行比较。
3．结合CDMA通信系统多用户检测的特点，采用遗传退火算法来进行CDMA的多用户检测。
Code division multiple access(CDMA) communications systems being possessed of the merits of great capacity and soft hand-off and so on must have taken a significant role in future wireless communications systems. Because PN sequences used in communications systems are been vertical completely , when numbers of user are more, there are multiple access interference(MAI) in CDMA and serving quality in communications systems is reduced. If interference are avoided and capacity of systems is increased, multi-user detection technology must be used in CDMA.
This paper introduces the application of the spread spectrum technology in communications. Aiming characteristic in CDMA communication systems, after we discuss some multi-user detection technology at present, and want to find a effective multi-user detection method with a small bit error rate in CDMA communication. Considering respective merits and disadvantages at simulated annealing algorithm and genetic algorithm, we combine them .By using simulated annealing algorithm(SA) to mitigate the stress of culling in genetic algorithm(GA) and utilizing the Boltzmann mechanism of simulated annealing algorithm to control the acceptance of the individuals generated by copulated and varied, a CDMA multi-user detection method based on genetic annealing algorithm is adopted. The computer simulative experiment is conducted. Satisfying result is got after analyze the simulation result. The result proved that the use of this algorithm will improve the performance of system and that the performance of system is better than the decorrelating multi-user detection. Experiments proved its efficiency.
The following is what I have done in this paper:
1.The paper systematically introduced the fundamental knowledge of Spread Spectrum Communication in CDMA , introduced multi-user detection technology in CDMA, and analysed advantages and flaws of multiuser detection technology.
2.The paper introduced SA and GA. Through the analysis of faults and merits of two algorithms,we combined Genetic Algorithm with Simulated Annealing Algorithm and formed a genetic annealing algorithm and applied to frequence assignment.
3.The paper used a multi-user detection based on genetic annealing algorithm.
引文
[1] 竺南直，肖辉等。《码分多址(CDMA)移动通信系统》．北京：电子工业出版社，1999。
[2] 王炎，程时听．基于CDMA的第三代移动通信系统．中兴新通讯，1997，6：20-24．
[3] 胡捍英，杨峰义．《第三带移动通信系统》．北京：人民邮电出版社，2001．
[4] 郭梯云，杨家玮等．《数字移动通信》．北京：人民邮电出版社，2001．
[5] William C. Y. Lee. Overview of Celular CDMA, IEEE Trans. VT, Vol.40, No,2,May, 1991.
[6] 胡建栋，郑朝晖等．《码分多址与个人通信》．北京：人民邮电出版社，1996
[7] 朱近康．《扩展频谱通信及其应用》．合肥：中国科技大学出版社，1993．
[8] 李承恕，赵朝黎．《扩展频谱通信》．北京：人民邮电出版社，1996．
[9] 尤肖虎等．第三代移动通信系统发展现状与展望．电子学报，第27卷增刊，1999(11)．
[10] Scholtz R. A. The origins of spread spectrum communications. IEEE Trans, Communication, 1982,COM-30(5).
[11] Pickholtz R. L, Schillinng D. L, Milstein L. B. Theory of spread spectrum communications-A Tutorial. IEEE Trans, Communications,1982, COM-30(5).
[12] J. K. Holmes. Coherent Spread Spectrum Systems. John-Wiley& Sons, 1982
[13] Gilhousen K, Jacobs I. etal. On the Capacity of a Cellular CDMA system. IEEE Ttans on Vehicular Technology, Vol.40,NO2,May 1991:303～312.
[14] Verdu S. Minimum Probability of Error for Asynchronous Gaussian Multiple Access Channels. IEEE Transaction on Information Theory, Vol.32,1986:85～96.
[15] Pursley M B, Performance Evaluation for Phase-Coded Spread-Spectrum Multiple-Access Communication. Part I:System Analysis, IEEE Trans. Commun,Vol.COM-25.1977:795～799.
[16] R T Behrens, L L Scharf. Signal Processing Applications of Oblique Projection Operator. IEEE Trans Signal Process, 1994,Vol 42:1413～1424
[17] 周月臣编著．移动通信工程设计[M]．北京：人民邮电出版社，1994．82
[18] R. Gold. Optimal binary sequences for spread spectrum multiplexing. IEEE Trans. Inform. Theory, Vol IT-13, No 4,1967.
[19] E. J. Groth. Generation of binary sequences with controllable complexity. IEEE
Trans. Inform. Theory, Vol IT-17, No 5,1971.
[20] Hallen A, Holtzman J, Zvonar Z. Multiuser Detection for CDMA System. IEEE Personal Commumication, 1995,2(2):46～58
[21] Moshavi S. Multiuser Detection for DS/CDMA Commumieation. IEEE Commumications Magazine. 1996,34(10): 124～136
[22] 夏鹏飞，李国清，夏斌，朱近康．CDMA通信系统中的多用户检测．现代电信科技，1999，(3)：34～38
[23] 肖磊，梁庆林．DS／CDMA系统中的抗多址干扰技术．电子科学学刊，2000，20 (2)：316～324
[24] B Aazhang, Bernd-Perter Paris, G Orsak. Neural networks for multiuser detection in code-division multiple-access communications. IEEE Trans. On Commun, 1992, 40:1212～1222
[25] Verdu S. Muitiuser Detection [M]. London:Cambridge University Press,1998.
[26] S Schneider. Optimum Detection of Code Division Multiplexed Signals.IEEE Trans Aer6space Elect Sys. Vol AES-15;Jan,1979:181～185
[27] A Duel-Hallen. Decorrelating decision-feedback multiuser detector for synchronous code-division multiple-access channel. IEEE Trans.On.Commun, 1993,41:285～290
[28] Madhow U, Honig M L. MMSE interference suppression for direct-sequence spread spectrum CDMA [J]. IEEE Trans On Comm, 1994, 42:3178～3188
[29] A. Gamst and W. Rave. On frequency assignment in mobile automatic telephone systems[J]. In Proc. IEEE GLOBECOM'82,1982, pp.309～315
[30] Lupas R, Verdu S. Linear multiuser detectors for synchronous code division multiple access channels. IEEE Trans. On Information Rheory, 1989,35:123～136
[31] S Moshavi, E G Kanterakis, D L Schilling. Multiage Linear Receivers for DS-CDMA Systems. Int'1 J Wireless Info Networks, Vol 3,No 1,Jan,1996
[32] JOHN G Proakis．数字通信[M]．北京：电子工业出版社，1998
[33] 康立山，谢云．非数值并行算法．模拟退火算法[M]．北京：科学出版社，1998
[34] A Duel-Hallen. A Family of Multi-User Decision-Feedback Detectors for Aysnchronous Code-Division Multiple Access Channels. IEEE Trans Commun, Vol 43, No 2/3/4, Frb/Mar/Apr,1995:421-434
[35] Varanasi M K, Aazhang B. Multistage detection in asynchronous code-division multiple-access communications. IEEE Trans Commun, 1990, 38(4):509～519
[36] A J Viterbi. Very Low Rate Con_volutional Codes for Maximum Theoretical Performance of Spread-Spectrum Multiple-Access Channels. IEEE JSAC, Vol 8,No 4, May, 1990:641～649
[37] R Kohno et al. Combination of Adaptive Array Antenna and a Canceller of Interference for Direct-Sequence Spread-Spectrum Multiple-Access System. IEEE JSAC Vol 8,No 4, May,1990:675-682
[38] Andrew L C Hui, Khaled Ben Letaief. Successive interference cancellation for multiuser asynchronous DS/CDMA detectors in multipath fading links. IEEE Trans.On Commun, 1998,46:384～391
[39] Hasegawa T T, Haneishi M. On the multiuser detection using a neueal network in code-division multiple-access communications. ICICE Trans Commun,1993, E76-H: 961～968
[40] U. Madhow. Blind adaptive interference suppression for direct sequence CDMA[A]. Proceeding. IEEE[C], 1998, 86(10):2049-2069
[41] Honig M, Madhow U, Verdu S. Blind adaptive multiuser detection[J]. IEEE Trans On IT, 1995,41 (4):944～960
[42] Verdu S. Optimum Multiuser Asymptotic Efficiency. IEEE Trans On Communication. 1986,34(9):890～897
[43] Krishnamuethy V. Averaged Stochastic Gradient Algorithms for Adaptive Blind Multiuser detection in DS/CDMA Systems. IEEE Trans On Communication, 2000,48(1):125～134
[44] Milstein L B. Interference Rejection Techniques in Spread Spectrum Communications. Proceedings of IEEE, 1986, 76(6):657～671
[45] Uesugi M, Kato O, Homma K. DS/CDMA System with Symbol Ranking Type Interference Canceller (SRIC). IEEE Trans On Communication, 1998, E81-B(7):1401～1408
[46] 王庆扬，张青，韦岗．CDMA移动通信系统中的多用户检测技术．移动通信，2000，2：41～45
[47] 陈顺林，杨万全．多用户检测技术的原理及其性能分析．实用测试技术，2002，1：1～3
[48] 黎海涛，徐继麟．多用户检测算法及其在IMT-2000中的应用．无线通信技术，2001，2：1～14
[49] 朱近康．CDMA通信技术．北京：人民邮电出版社，2001．
[50] Holland J H. Adaptation in Natural and Artificial Systems. MIT Press, 1975
[51] Holland J H．基因算法．科学，1992，11：24～31
[52] 陈国良，王煦法，庄镇泉，王东生．遗传算法及其应用．北京：人民邮电出版社，1996
[53] Potts J C, etal. The Development and Evaluation of an Improved Genetic Algorithm Based on Migration and Aritificial Selection. IEEE Trans Systman,
Cybern, 1994, 24(1): 73～86
[54] Feng Q X, Francesco E Theoretical Analysis of Evolutionary Algorithms with an Infinite Population Size in Continuous Sprace Part I and Ⅱ: Basic Properties of Selection and Mutation. IEEE Trans Neural Networks, 1994, 5(1): 102～129
[55] Fogarty J C. Varying the Probability of Mutation in Genetic Algorithms. In Proc 3rd Int Conf Genetic Algorithms, 1989,42～50
[56] Goldberg D E. Genetic Algorithms and Wolsh Function: Part Ⅱ. Deception and Its Analysis, Complex Syst, 1989,3:153～171
[57] Goldberg D E. Optimal Initial Population Size for Binarycoded Genetic Algorithms (TCGA Report No. 85001). University of Alabama, The Clearing-house for Genetic Algorithms, 1985
[58] David. Beasley, D. R. Bull, and R. R. Martin, An overview of Genetic Algorithm: Part Ⅰ, Fundamentals, University Computing, Vol. 15 No.2, 58～69,1993
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[63] X. Wang, H. V. Poor. Blind multiuser detection. A subspace approach[J]. IEEE Transactions On IT, 1998, 44(2):677～690
[2] 王炎，程时听．基于CDMA的第三代移动通信系统．中兴新通讯，1997，6：20-24．
[3] 胡捍英，杨峰义．《第三带移动通信系统》．北京：人民邮电出版社，2001．
[4] 郭梯云，杨家玮等．《数字移动通信》．北京：人民邮电出版社，2001．
[5] William C. Y. Lee. Overview of Celular CDMA, IEEE Trans. VT, Vol.40, No,2,May, 1991.
[6] 胡建栋，郑朝晖等．《码分多址与个人通信》．北京：人民邮电出版社，1996
[7] 朱近康．《扩展频谱通信及其应用》．合肥：中国科技大学出版社，1993．
[8] 李承恕，赵朝黎．《扩展频谱通信》．北京：人民邮电出版社，1996．
[9] 尤肖虎等．第三代移动通信系统发展现状与展望．电子学报，第27卷增刊，1999(11)．
[10] Scholtz R. A. The origins of spread spectrum communications. IEEE Trans, Communication, 1982,COM-30(5).
[11] Pickholtz R. L, Schillinng D. L, Milstein L. B. Theory of spread spectrum communications-A Tutorial. IEEE Trans, Communications,1982, COM-30(5).
[12] J. K. Holmes. Coherent Spread Spectrum Systems. John-Wiley& Sons, 1982
[13] Gilhousen K, Jacobs I. etal. On the Capacity of a Cellular CDMA system. IEEE Ttans on Vehicular Technology, Vol.40,NO2,May 1991:303～312.
[14] Verdu S. Minimum Probability of Error for Asynchronous Gaussian Multiple Access Channels. IEEE Transaction on Information Theory, Vol.32,1986:85～96.
[15] Pursley M B, Performance Evaluation for Phase-Coded Spread-Spectrum Multiple-Access Communication. Part I:System Analysis, IEEE Trans. Commun,Vol.COM-25.1977:795～799.
[16] R T Behrens, L L Scharf. Signal Processing Applications of Oblique Projection Operator. IEEE Trans Signal Process, 1994,Vol 42:1413～1424
[17] 周月臣编著．移动通信工程设计[M]．北京：人民邮电出版社，1994．82
[18] R. Gold. Optimal binary sequences for spread spectrum multiplexing. IEEE Trans. Inform. Theory, Vol IT-13, No 4,1967.
[19] E. J. Groth. Generation of binary sequences with controllable complexity. IEEE
Trans. Inform. Theory, Vol IT-17, No 5,1971.
[20] Hallen A, Holtzman J, Zvonar Z. Multiuser Detection for CDMA System. IEEE Personal Commumication, 1995,2(2):46～58
[21] Moshavi S. Multiuser Detection for DS/CDMA Commumieation. IEEE Commumications Magazine. 1996,34(10): 124～136
[22] 夏鹏飞，李国清，夏斌，朱近康．CDMA通信系统中的多用户检测．现代电信科技，1999，(3)：34～38
[23] 肖磊，梁庆林．DS／CDMA系统中的抗多址干扰技术．电子科学学刊，2000，20 (2)：316～324
[24] B Aazhang, Bernd-Perter Paris, G Orsak. Neural networks for multiuser detection in code-division multiple-access communications. IEEE Trans. On Commun, 1992, 40:1212～1222
[25] Verdu S. Muitiuser Detection [M]. London:Cambridge University Press,1998.
[26] S Schneider. Optimum Detection of Code Division Multiplexed Signals.IEEE Trans Aer6space Elect Sys. Vol AES-15;Jan,1979:181～185
[27] A Duel-Hallen. Decorrelating decision-feedback multiuser detector for synchronous code-division multiple-access channel. IEEE Trans.On.Commun, 1993,41:285～290
[28] Madhow U, Honig M L. MMSE interference suppression for direct-sequence spread spectrum CDMA [J]. IEEE Trans On Comm, 1994, 42:3178～3188
[29] A. Gamst and W. Rave. On frequency assignment in mobile automatic telephone systems[J]. In Proc. IEEE GLOBECOM'82,1982, pp.309～315
[30] Lupas R, Verdu S. Linear multiuser detectors for synchronous code division multiple access channels. IEEE Trans. On Information Rheory, 1989,35:123～136
[31] S Moshavi, E G Kanterakis, D L Schilling. Multiage Linear Receivers for DS-CDMA Systems. Int'1 J Wireless Info Networks, Vol 3,No 1,Jan,1996
[32] JOHN G Proakis．数字通信[M]．北京：电子工业出版社，1998
[33] 康立山，谢云．非数值并行算法．模拟退火算法[M]．北京：科学出版社，1998
[34] A Duel-Hallen. A Family of Multi-User Decision-Feedback Detectors for Aysnchronous Code-Division Multiple Access Channels. IEEE Trans Commun, Vol 43, No 2/3/4, Frb/Mar/Apr,1995:421-434
[35] Varanasi M K, Aazhang B. Multistage detection in asynchronous code-division multiple-access communications. IEEE Trans Commun, 1990, 38(4):509～519
[36] A J Viterbi. Very Low Rate Con_volutional Codes for Maximum Theoretical Performance of Spread-Spectrum Multiple-Access Channels. IEEE JSAC, Vol 8,No 4, May, 1990:641～649
[37] R Kohno et al. Combination of Adaptive Array Antenna and a Canceller of Interference for Direct-Sequence Spread-Spectrum Multiple-Access System. IEEE JSAC Vol 8,No 4, May,1990:675-682
[38] Andrew L C Hui, Khaled Ben Letaief. Successive interference cancellation for multiuser asynchronous DS/CDMA detectors in multipath fading links. IEEE Trans.On Commun, 1998,46:384～391
[39] Hasegawa T T, Haneishi M. On the multiuser detection using a neueal network in code-division multiple-access communications. ICICE Trans Commun,1993, E76-H: 961～968
[40] U. Madhow. Blind adaptive interference suppression for direct sequence CDMA[A]. Proceeding. IEEE[C], 1998, 86(10):2049-2069
[41] Honig M, Madhow U, Verdu S. Blind adaptive multiuser detection[J]. IEEE Trans On IT, 1995,41 (4):944～960
[42] Verdu S. Optimum Multiuser Asymptotic Efficiency. IEEE Trans On Communication. 1986,34(9):890～897
[43] Krishnamuethy V. Averaged Stochastic Gradient Algorithms for Adaptive Blind Multiuser detection in DS/CDMA Systems. IEEE Trans On Communication, 2000,48(1):125～134
[44] Milstein L B. Interference Rejection Techniques in Spread Spectrum Communications. Proceedings of IEEE, 1986, 76(6):657～671
[45] Uesugi M, Kato O, Homma K. DS/CDMA System with Symbol Ranking Type Interference Canceller (SRIC). IEEE Trans On Communication, 1998, E81-B(7):1401～1408
[46] 王庆扬，张青，韦岗．CDMA移动通信系统中的多用户检测技术．移动通信，2000，2：41～45
[47] 陈顺林，杨万全．多用户检测技术的原理及其性能分析．实用测试技术，2002，1：1～3
[48] 黎海涛，徐继麟．多用户检测算法及其在IMT-2000中的应用．无线通信技术，2001，2：1～14
[49] 朱近康．CDMA通信技术．北京：人民邮电出版社，2001．
[50] Holland J H. Adaptation in Natural and Artificial Systems. MIT Press, 1975
[51] Holland J H．基因算法．科学，1992，11：24～31
[52] 陈国良，王煦法，庄镇泉，王东生．遗传算法及其应用．北京：人民邮电出版社，1996
[53] Potts J C, etal. The Development and Evaluation of an Improved Genetic Algorithm Based on Migration and Aritificial Selection. IEEE Trans Systman,
Cybern, 1994, 24(1): 73～86
[54] Feng Q X, Francesco E Theoretical Analysis of Evolutionary Algorithms with an Infinite Population Size in Continuous Sprace Part I and Ⅱ: Basic Properties of Selection and Mutation. IEEE Trans Neural Networks, 1994, 5(1): 102～129
[55] Fogarty J C. Varying the Probability of Mutation in Genetic Algorithms. In Proc 3rd Int Conf Genetic Algorithms, 1989,42～50
[56] Goldberg D E. Genetic Algorithms and Wolsh Function: Part Ⅱ. Deception and Its Analysis, Complex Syst, 1989,3:153～171
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