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摘要:
线缆耦合是航电系统电磁干扰问题的主要来源之一,对其进行监测具有重要意义。利用线缆束中的非功能线作为监测线,实现了一种对功能线缆耦合到的干扰信号进行实时监测的方法。由于监测线与被测线具有相似的干扰场分布和布线路径,因此可以抵消二者的未知性和随机性带来的影响。将监测线与被测线视为相同的二端口网络,建立采用
矩阵描述的端口电流相互关系,进而利用传输线理论建立频域解析模型,将其转化为离散时间模型并给出系统的信号流图,为硬件实现提供基础。以一个四芯传输线系统为例对本文方法进行了验证,与实测结果对比,端口电流峰值误差不超过6%,验证了本文方法的有效性和精度。ABCD Abstract:Cable coupling is one of the most important reasons for electromagnetic compatibility problems in avionics systems. Monitoring the cable coupling effect is of great significance. A method of monitoring the coupling signals on the ports with the spare wire in the cable is introduced. Since the monitoring wire is in the same conditions as the monitored one, the influence of the stochastic routing and field distribution could be counteracted. The monitoring and monitored wires could be regarded as the same two-port system, which could be described with an ABCD matrix. Then the frequency-domain analytical model of this system could be constructed with the transmission line theory. Finally, it could be converted to a discrete-time model and the signal flow graphs of the system could be achieved, which is convenient for the real-time signal processing and hardware realization. A four-wire cable system is taken as the case to validate the method. Compared with the results of measurement, the errors of the current peaks are less than 6%, which is small enough for practical applications. This fact proves that the method is effective and accurate.
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[1] 苏东林, 谢树果, 戴飞, 等.系统级电磁兼容性量化设计理论与方法[M].北京:国防工业出版社, 2015:125.SU D L, XIE S G, DAI F, et al.The theory and method of quantification design on system-level electromagnetic compatibility[M].Beijing:National Defense Industry Press, 2015:125(in Chinese). [2] PAUL C R.Introduction to electromagnetic compatibility[M].2nd ed. Hoboken, NJ:Wiley, 2006:503-557. [3] PAUL C R.Analysis of multiconductor transmission lines[M].2nd ed.New York:Wiley-IEEE, 2007:89-109. [4] WANG Y M, SU D L, CHEN W Q.Analysis of field-to-transmission line coupling in the airplane[C]//ISAPE 20088th International Symposium.Piscataway, NJ:IEEE Press, 2008:1052-1055. [5] LI B, WANG J J, SONG X W, et al.Equivalent circuit model of frequency-domain responses with external field[C]//2015 IEEE International Symposium on Electromagnetic Compatibility.Piscataway, NJ:IEEE Press, 2015:761-766. [6] PIGNARI S A, SPADACINI G.Plane-wave coupling to a twisted-wire pair above ground[J].IEEE Transactions on Electromagnetic Compatibility, 2011, 53(2):508-523. doi: 10.1109/TEMC.2010.2061855 [7] JULLIEN C, BESNIER P, DUNAND M, et al.Advanced modeling of crosstalk between an unshielded twisted pair cable and an unshielded wire above a ground plane[J].IEEE Transactions on Electromagnetic Compatibility, 2013, 55(1):183-194. doi: 10.1109/TEMC.2012.2206599 [8] SPADACINI G, PIGNARI S A.Numerical assessment of radiated susceptibility of twisted-wire pairs with random nonuniform twisting[J].IEEE Transactions on Electromagnetic Compatibility, 2013, 55(5):956-964. doi: 10.1109/TEMC.2012.2235446 [9] 张莉.同轴电缆屏蔽性能测量方法的比较[J].电线电缆, 2014(6):21-23. http://www.cnki.com.cn/Article/CJFDTOTAL-DXDL201406008.htmZHANG L.Comparison of coxial cable shielding effectiveness measurement methods[J].Electric Wire & Cable, 2014(6):21-23(in Chinese). http://www.cnki.com.cn/Article/CJFDTOTAL-DXDL201406008.htm [10] 齐磊, 崔翔, 谷雪松.屏蔽电缆转移阻抗和转移导纳的宽频测量[J].电波科学学报, 2007, 22(4):696-701. http://www.cnki.com.cn/Article/CJFDTOTAL-DBKX200704032.htmQI L, CUI X, GU X S.Wide-frequency measurement of transfer impedance and transfer admittance of shielded cable[J].Chinese Journal of Radio Science, 2007, 22(4):696-701(in Chinese). http://www.cnki.com.cn/Article/CJFDTOTAL-DBKX200704032.htm [11] IEC.Metallic communication cable test methods:CEI/IEC 62153-4-620066[S].Geneva:IEC, 2006. [12] Boeing Design Manual.Wiring design, assembly and installation:BDM-7124[S].Seattle:Boeing, 1991. [13] 陈穷, 蒋全兴, 周开基, 等.电磁兼容性工程设计手册[M].北京:国防工业出版社, 1993:424-444.CHEN Q, JIANG Q X, ZHOU K J, et al.Electromagnetic compatibility engineering design manual[M].Beijing:National Defense Industry Press, 1993:424-444(in Chinese). [14] 中国人民解放军总装备部. 军用设备和分系统电磁发射和敏感度要求与测量: GJB 151B-2013[S]. 北京: 中国标准出版社, 2013.PLA General Equipment Department.Electromagnetic emission and susceptibility requirements and measurements for military equipment and subsystems:GJB 151B-2013[S].Beijing:Standards Press of China, 2013(in Chinese). [15] OPPENHEIM A V, SCHAFER R W, BUCK J R.Discrete-time signal processing[M].2nd ed.Upper Saddle River, NJ:Prentice Hall, 1998:340-438.