一种星载通信混合反射面天线的设计方法

为了使星载通信天线产生1个赋形波束覆盖服务区，同时产生1个固定点波束和1个有限扫描点波束，该文提出一种由2个赋形反射面和3个馈源组成的混合反射面天线。该天线是以赋形主反射面共用为基础，等效为2副单馈源单偏置反射面天线和1副双偏置格里高利型赋形反射面天线，分别产生赋形波束、固定点波束和有限扫描点波束。通过对一副口径为1.2 m的天线各个波束进行仿真实验，赋形波束在Ku收、发频段时波束覆盖区边缘(EoC)方向性系数为27.5 dBi，固定点波束在C收、发频段时天线口径效率高于70%，通过将赋形副反射面及对应馈源横向偏焦实现Ka收、发频段的点波束在服务区内外的扫描。仿真结果表明，该混合反射面天线可实现C/Ku/Ka频段的同时通信任务。

A Synthesis Method of Hybrid Reflector Antenna for Satellite Communications

A hybrid reflector antenna is presented to generate a contoured beam over service area, an un-scanned and a scanned pencil beam from two shaped reflectors and three feeds, simultaneously. The shaped main reflector is shared by three beams, and the antenna is equivalent to two single-reflector antennas with single-feed for each beam and a pair of dual offset Gregorian shaped reflector antennas, and generating the contoured, un-scanned and scanned pencil beam, respectively. The proposed method is successfully applied to a 1.2 m hybrid reflector antenna. Simulations and experimentations of each beam has been performed. The Edge of Coverage(EoC) directivity over service area is 27.5 dBi for contoured beam in Tx and Rx working frequency of Ku-band, and the un-scanned pencil beam has a aperture efficiency higher than 70% in Tx and Rx working frequency of C-band. Meanwhile, the scanned pencil beam inside and outside the service area is realized by the lateral defocus of the sub-reflector and the corresponding feed in Tx and Rx working frequency of Ka-band. Simulation results show that the hybrid reflector antenna can realize C/Ku/Ka-band communication tasks simultaneously.