聚能定向电磁脉冲天线设计+文献综述(2)
时间:2018-10-22 20:22 来源:毕业论文 作者:毕业论文 点击:次
For the study on radiation characteristics, firstly, the pyramid horn is determined as the feed, and the radiation pattern model is established; then, the radiation efficiency model of the feed is established, considering effects from the port amplitude drop, and E-plane and H-plane distribution; after that, the far field distribution of the paraboloid is developed based on port field distribution which is obtained according separate analysis on its geometric optical characteristics, so that the directional coefficient model of the paraboloid is established; and, the radiation efficiency model of the paraboloid is established through considering effects of port distribution and spillage; finally, the total gain model is established combined models above. For doing structural optimization, the chaos particle subgroup optimization (CPSO) is applied, and the ideal optimal gain is 36.88dB, and the optimal structural sizes are determined; then, the relationship curves between the total gain and structural sizes are indicated based on engineering discrete method, and the approximate optimal location is determined, verifying the accuracy of algorithm solution. The results indicate that the algorithm solution is more accurate, and the optimal gain is 0.39dB higher than that based on discrete method. After that, the parachute-bomb system is designed and its patterns, relative amplitudes, frequency characteristics and efficiency characteristics are analyzed, and the relationships between critical power and action radius under four efficiency levels are developed. The analysis results show that this parachute antenna is directional significantly, and performs well in the middle frequency segment, with frequency width, 10.8dB and optimal gain, 41dB. For further verification of the parachute antenna, the simulation is done based on software Ansoft HFSS, and its electric characteristic parameters, patterns, relative amplitudes are obtained and compare with those from theoretical calculation, verifying the theoretical model. The gain based on simulation is 34.4dB, and the efficiency is 0.4 approximately, which are slightly smaller than the simplified theoretical results. Keywords electromagnetic pulse antenna parachute antenna gain radiation efficiency chaos particle subgroup optimization 目 次 1绪论 1 1.1 课题背景 1 1.2 国内外研究现状… 2 1.3 研究内容 10 1.4 本章小结 11 2伞形天线弹药工作原理与动力学建模… 13 2.1 工作过程 13 2.2 总体结构分析 14 2.3 伞弹弹道模型 14 2.4 伞弹动力学分析… 18 2.5 伞形天线口径优化 23 2.6 本章小结 25 3 天线增益建模… 26 3.1 方向系数与增益… 26 3.2 馈源辐射效率 28 3.3 抛物面几何关系及几何光学特性 33 3.4 口径场法分析 35 3.5 抛物面结构增益… 37 3.6伞形天线总增益 39 3.7 本章小结 39 4伞形天线结构优化… 40 4.1 粒子群算法… 40 4.2 混沌粒子群算法优化… 42 4.3 工程离散法验证… 45 4.4 优化结构分析 46 4.5 本章小结 47 5伞形天线弹药结构设计和性能分析 48 5.1 结构设计 48 5.2 馈源电特性分析… 49 5.3 伞形天线电特性计算… 50 5.4 频率特性分析 51 5.5 效能分析 51 5.6 本章小结 53 6 伞形天线仿真… 54 6.1 HFSS-IE求解器… 54 6.2 仿真计算模型 54 6.3 仿真结果分析 55 6.4 本章小结 57 结论 58 致谢 59 参考文献…60 附录A 龙格-库塔法求解代码 64 附录B 混沌粒子群优化算法代码 67 1 绪论 1.1 课题背景 随着电子技术在现代战争中的广泛应用，军事设备的电磁敏感度越来越高，而在智能化与小型化的同时，对电磁干扰的易损性也增加了[1]，因此对军事设备的软杀伤在战场攻防中的地位日益突出。电磁脉冲武器由于作用距离远，软硬杀伤能力兼备，使用时所带来的政治上的负面影响远小于普通弹药，对雷达，电网，控制设施等电子设备有着巨大的毁伤作用，及效费比高等优势，因此其研制工作逐渐成为各国的焦点之一[2]，在当代局部战争中也得到了重要应用，效果显著。 (责任编辑：qin) |