文章快速检索 高级检索

Influence of EUT radiated emission testing location on test results
LYU Dongxiang , SU Donglin
School of Electronic and Information Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China
Received: 2016-02-06; Accepted: 2016-04-01; Published online: 2016-04-13 11:32
Foundation item: National Natural Science Foundation of China (61427803, 61221061)
Corresponding author. E-mail:sdl@buaa.edu.cn
Abstract: In order to improve the measurement precision and reduce the influence of equipment under test (EUT) electromagnetic radiated emission testing location on test results in electromagnetic capatibility (EMC) semi-anechoic chamber, this paper studies the influence law on electromagnetic signal radiation emission testing of semi-anechoic chamber typical resonance frequency for different testing locations of semi-anechoic chamber. The research is modeled, simulated and calculated by geometrical optics, consistency of diffraction theory and multipath effect algorithm. The math model and computational formulas are proposed, besides, the influence of direct field is eliminated in the math model. The electromagnetic propagation effects of reflection, refraction and multipath effect in the testing are comprehensively considered. The calculation results of math propagation model and actual testing model that eliminate the influence of direct field are compared. The results verify the effectiveness of math model. This research supplies theory basis for correcting the results of electromagnetic radiation emission testing in different positions of semi-anechoic chamber, which is also helpful to improving the measurement precision of electromagnetic radiation emission testing in semi-anechoic chamber.
Key words: electromagnetic radiated emission     semi-anechoic chamber     testing location     measurement precision     electromagnetic compatibility

1 数学建模与计算

 图 1 半电波暗室静区标准点位试验示意图 Fig. 1 Schematic diagram of standard location testing inquiet zone of semi-anechoic chamber

 (1)

 图 2 电磁波经过吸波材料传播路径图 Fig. 2 Propagation path of electromagnetic wavethrough absorber material

 (2)
 (3)

 图 3 电磁信号多路径反射传输示意图 Fig. 3 Schematic diagram of multipath reflection transmission of electromagnetic signal
 (4)

 (5)

 (6)

 (7)
 (8)
 (9)

 (10)

 (11)

 (12)

 (13)

 (14)

 (15)

 (16)

 m q p f0/MHz 0 1 1 21.7 0 2 1 31.0 0 3 1 42.0 0 4 1 53.8 0 5 1 66.0 0 6 1 78.3 0 7 1 90.7 0 8 1 103.2 0 9 1 115.8

 图 4 半电波暗室中典型试验点位选取示意图 Fig. 4 Schematic diagram of selection of typical testinglocation in semi-anechoic chamber
 图 5 半电波暗室内不同试验点位典型谐振频率剔除直射场强数学模型计算结果 Fig. 5 Calculation results of typical resonant frequencysignal mathematical model in different testing locations ofsemi-anechoic chamber with direct field strength eliminated

2 试验验证

 图 6 半电波暗室及开阔场试验场景图 Fig. 6 Semi-anechoic chamber open area testing scene

 (17)

 (18)

 图 7 半电波暗室内不同试验点和开阔场典型谐振频率辐射发射实测模型计算结果 Fig. 7 Calculation results of typical resonant frequencyradiated emission actual testing model in different testinglocation of semi-anechoic chamber and in open area

 图 8 不同试验点位典型谐振频率数学模型和实测模型剔除直射场强计算结果对比图 Fig. 8 Calculation results comparison diagram of typicalresonant frequency mathematical model and actual testingmodel in different testing locations with direct fieldstrength eliminated

 图 9 不同试验点位典型谐振频率实测模型和数学传播模型差值计算结果 Fig. 9 Difference value calculation results of typical resonantfrequency actual testing and math propagation model indifferent testing locations

3 结 论

1) 通过对半电波暗室中进行的辐射发射试验进行计算，给出了半电波暗室中不同试验点位的电磁辐射发射传播的数学计算模型，并对模型进行了试验验证。

2) 建立数学模型和试验实测模型后，剔除了直射场影响，并通过分析数学模型和实测模型的计算结果，比对不同试验点位，实测模型和数学传播模型在暗室典型谐振频率的差值，验证了数学计算模型的有效性。

3) 为数学修正暗室中不同试验点位的电磁辐射发射测试结果提供了理论依据，具有一定的理论参考价值，有助于提高暗室中电磁辐射发射试验的测试精度。

 [1] Electronic Information Department of General Armament Department of the Chinese People's Liberation Army. Requirements and measurement of electromagnetic emission and susceptibility for military equipment and subsystems:GJB 151B-2013[J]. Beijing:Commission of Science Technology and Industry for National Defense of the PRC, 2013 : 59 –65. [2] HENRY W O. Electromagnetic compatibility engineering[M]. NewYork: Wiley, 2009 : 116 -148. [3] 马永光, 陈海波, 何国瑜. 射频仿真暗室的静区分析[J]. 北京航空航天大学学报, 2006, 32 (12) : 1431 –1434. MA Y G, CHEN H B, HE G Y. Quiet zone analysis of a RF simulation anechoic chamber[J]. Journal of Beijing University of Aeronautics and Astronautics, 2006, 32 (12) : 1431 –1434. (in Chinese) [4] SHINOZAKI A, SASAKI R, HARIYA E. Performance comparison of 10 m semi-anechoic chamber for EMI measurement using CISPR16-1:Anechoic chamber performance verification experiment report using CALT theoretical value[J]. IEICE Technical Report Electromagnetic Compatibility, 2004, 104 : 19 –26. [5] 洪丽娜, 樊友谊, 郝晓军, 等. 吸波材料电参数改变对暗室静区性能的影响分析[J]. 电子测量技术, 2010, 33 (8) : 121 –124. HONG L N, FAN Y Y, HAO X J, et al. Analysis on the quiet zone performance due to degraded absorbers[J]. Electronic Measurement Technology, 2010, 33 (8) : 121 –124. (in Chinese) [6] HAO X,LIU R,CHEN Y,et al.Calculation and optimization of quiet-zone in RF anechoic chamber[C]//7th IEEE International Symposium on Antennas,Propagation & EM Theory,2006(ISAPE'06).Piscataway,NJ:IEEE Press,2006:1-3. [7] SONG D A,FANG C,ZHANG Q,et al.The technologies for reducing quiet zone level of anechoic chamber[C]//IEEE International Symposium on Signals Systems and Electronics(ISSSE),2010. [8] CHANG D C, LIAO C H, WU C C. Compact antenna test range without reflector edge treatment and RF anechoic chamber[J]. IEEE Antennas & Propagation Magazine, 2004, 46 (4) : 27 –37. [9] SPANO I L,SULIS S,SERPI A,et al.EMC Characterization of implantable cardiac medical devices in an anechoic chamber[C]//2014 IEEE International Symposium on Electromagnetic Compatibility(EMC Europe).Piscataway,NJ:IEEE Press,2014:872-877. [10] KURIHARA H, SAITO T, SUZUKI Y, et al. Investigation on 10 m semi anechoic chamber by using grid-ferrite and open-top hollow pyramidal EM wave absorber[J]. IEICE Transactions on Electronics, 2006, 89 (1) : 16 –23. [11] 何洋, 苏东林, 李艳, 等. 一种电磁兼容测量天线系数温度误差修正方法[J]. 北京航空航天大学学报, 2015, 41 (10) : 1821 –1829. HE Y, SU D L, LI Y, et al. Method for EMC antenna factor temperature error correction[J]. Journal of Beijing University of Aeronautics and Astronautics, 2015, 41 (10) : 1821 –1829. (in Chinese) [12] 苏东林, 戴飞, 谢树果, 等. 天线系数的测试误差与NSA测试的改进[J]. 北京航空航天大学学报, 2007, 33 (11) : 1291 –1294. SU D L, DAI F, XIE S G, et al. Errors of antenna factor and improved method for NSA test[J]. Journal of Beijing University of Aeronautics and Astronautics, 2007, 33 (11) : 1291 –1294. (in Chinese) [13] LIN M S,JI J M,HSU C I G,et al.Simulation and analysis of emc chambers by ray tracing method[C]//IEEE International Symposium on Electromagnetic Compatibility,2007(EMC 2007).Piscataway,NJ:IEEE Press,2007:1-4. [14] MIGLIORE M D. Filtering environmental reflections in far-field antenna measurement in semi-anechoic chambers by an adaptive pattern strategy[J]. IEEE Transactions on Antennas & Propagation, 2004, 52 (4) : 1112 –1115. [15] 吴良超, 汪茂光. 阻抗劈一致性绕射系数的一种简洁表达式[J]. 电波科学学报, 1994 (4) : 76 –80. WU L C, WANG M G. A concise expression of uniform diffracted coefficient of an impedance wedge[J]. Chinese Journal of Radio Science, 1994 (4) : 76 –80. (in Chinese) [16] 唐东, 张麟兮, 呼斌, 等. 基于距离差分法消除天线测试多径干扰[J]. 现代电子技术, 2014 (11) : 101 –103. TANG D, ZHANG L X, HU B, et al. Elimination of multipath interference in antenna test based on distance difference method[J]. Modern Electronics Technique, 2014 (11) : 101 –103. (in Chinese) [17] CHUNG B K, CHUAH H T. Design and construction of a multipurpose wideband anechoic chamber[J]. IEEE Antennas & Propagation Magazine, 2003, 45 (6) : 41 –47. [18] HERRERA J F, MORENO P. Calculation of reflection losses in a small anechoic chamber[J]. IEEE Latin America Transactions, 2015, 13 (5) : 1258 –1264. DOI:10.1109/TLA.2015.7111977 [19] MUNTEANU I, KAKEROW R. Simulation methodology for the assessment of field uniformity in a large anechoic chamber[J]. IEEE Transactions on Magnetics, 2014, 50 (2) : 213 –216. DOI:10.1109/TMAG.2013.2283154

文章信息

LYU Dongxiang, SU Donglin

Influence of EUT radiated emission testing location on test results

Journal of Beijing University of Aeronautics and Astronsutics, 2017, 43(1): 100-106
http://dx.doi.org/10.13700/j.bh.1001-5965.2016.0121