基于阵列馈电的深空探测广视场电大反射面天线研究

To compensate for the huge path loss, the ground antennas intended for deep-space exploration require large apertures operating at high frequencies with sharp pencil beam. Under a rough orbit forecast,the deep-space exploration range is challenged by the time of capturing spacecraft using a narrow beam-width antenna. According to major strategic needs for deep space exploration in China, the project concerns on the theory and technique of the phased-array-fed （PAF）large reflector antenna with wide field of view and accurate beam.Based the theory of active impedance,the dynamic performance of the PAF large reflector antenna is investgated during beam scanning,and the united dynamic performance model of PAF reflector antenna is proposed. The match condition is established between the pattern of PAF and the second pattern of reflector antenna with the surface current distribution on reflector.Controlling the reflector aperture field amplitude, phase distribution using PAF,the field of view of PAF large antenna has been enlarged. Under the overall system performance constraints,the objective function is proposed and optimised using articical intelligence,and the desired pattern of PAF large reflector antenna is synthesized. The range of deep space exploration will be promoted by the antenna with works of this project.

为弥补超远距离深空探测的超大路径损耗，增加地面测控天线口径及提升天线工作频率皆导致天线波束变窄。现有粗轨道预报下窄波束天线对深空探测器的快速捕获问题已经成为制约探测距离的关键，亟待解决。针对我国深空探测的重大战略需求，课题研究基于阵列馈电的具有广视场、精确指向的深空探测电大反射面天线理论和技术。基于有源阻抗理论，探索阵列馈电反射面天线在波束扫描时的动态性能，建立基于有源阻抗理论的阵列馈电反射面天线的统一性能模型。以反射面上的面电流分布为研究对象，通过建立馈电阵列方向图与反射面天线次级方向图的匹配模型，调控窄波束反射面天线口面场的幅、相分布，突破阵列馈电反射面天线的可视范围的瓶颈，解决窄波束反射面广视场研究中的基础性问题。从全局系统性能约束构造目标函数，应用人工智能优化综合具有精确指向的波束。课题成果将为用于超远距离探测的广视场窄波束天线性能的提升提供理论基础和新思路。

经过3年的系统研究，项目阐明了阵列馈电反射面天线在波束扫描时动态性能机理，建立基于有源阻抗理论的阵列馈电反射面天线的统一模型。从反射面上的面电流分布着手，调控窄波束反射面天线的口面场的幅、相分布，突破了阵列馈电反射面天线可视范围的瓶颈，解决了窄波束反射面广视场研究中的基础性问题。从全局系统性能约束构造目标函数，优化综合，为深空探测电大反射面天线技术的发展提供新思路和理论依据。在完成以上原定研究计划基础上，开展了基于超材料的极化域调控研究及基于稀疏阵列应用于相控阵焦面阵的来波方向估计研究，为深空探测大天线的发展和应用提供新思路。基于阵列天线的相关研究成果结合超宽带距离测量技术已经应用于输电线路的舞动技术监测。