Co-aperture arrangement of dual antennas for orientation and telemetry in a conformal cavity

The feasibility of making two antennas work within a shared aperture conformai to a platform like an aircraft or a missile is investigated. The shared aperture is enclosed by a deep cavity, which is covered by a columniform dielectric radome. A modified quadrifilar helix antenna （QHA） with extended volute arms and a vertical monopole with a ring shaped ground are arranged in this co-aperture for global position system （GPS） orientation and telemetry, respectively. The effects of the cavity on these two antennas and the mutual coupling between these two antennas are studied through large numbers of experiments. The results show that the QHA has a strong influence on the monopole; however, these two antennas of the overall arrangement can perform simultaneously well within the aperture. The QHA has a right hand circular polarization （RHCP） and a broad beam normal to the radome topside, meanwhile the monopole can be used to produce a main lobe in the grazing direction above the aperture in some certain cases of the vertical location of the QHA in the cavity.

面向工程应用能力提升的电磁散射高效数值分析:进展与挑战

本文介绍了在先进高效数值方法—多层快速多极子方法(Multilevel Fast Multipole Algorithm,MLFMA)分析框架下,旨在进一步提升数值求解能力和工程应用能力的研究成果,以及结合相关成果的应用研究;重点讨论了用于超电大目标(特别是含腔目标)散射分析的各型相位提取(Phase Extracted,PE)基函数、用于金属-厚介质层复合结构散射建模的电流磁流混合场积分方程(Electric and Magnetic Current Combined Field Integral Equation,JMCFIE)、用于天线罩及雷达仓散射计算的多层介质散射的多层薄介质层(Thin Dielectric Sheet,TDS)边界条件方法、用于多尺度结构电磁散射建模的快速笛卡尔展开方法;并给出了相关应用实例.最后,对当前仍然存在的主要挑战和可能的对策进行了简略的讨论和展望.

定位／通信双天线深腔共口径实验研究

该文对载体平台上双天线共口径的可行性进行了研究,口径为带介质罩的深腔。定位天线采用四绕螺旋天线(QHA);通信天线采用以腔壁为地的水平单极振子。对QHA天线在腔内的应用提出了利用腔底与末端水平支节进行调谐的改进。通过理论分析和实验考察了腔体对天线及两副天线之间的影响。结果表明这种方案中的两副天线能够同时在腔内很好地工作,相互的耦合还展宽了水平振子的工作带宽。

厚介质罩深腔内双天线共口径设计

对在载体平台上带介质罩的深腔内实现双天线共口径的可行性进行了研究。四绕螺旋天线(QHA)被采用以实现载体定位;环状地板上的竖直单极振子或二元阵则用于遥测。实验研究了腔体对天线及两副天线之间的影响。结果表明这种方案中的两副天线能够同时很好地工作,QHA天线窗口法向右旋圆极化(RHCP)辐射,遥测天线口径面掠射,同时相互的耦合还展宽了遥测天线的工作带宽。