星载共口径多波束赋形反射面天线设计

Design of common aperture multi-beam shaped reflector antenna for satellite communications

为了满足星载通信中多任务并行需求,提出了一种由格里高利型反射面和三个馈源喇叭天线组成的共口径多波束反射面天线,该天线能够产生两个固定轮廓波束和一个点波束。天线设计是采用射线追踪法确定点波束馈源位置以建立天线基础结构,并通过Zernike多项式和Cubic B-splines函数共同对主、副反射面进行赋形优化来完成。为了验证该方法的有效性,对口径为1.1 m的天线进行仿真设计,结果表明两个赋形轮廓波束在Ku收、发频段边缘增益(EOC gain)分别为27.7、28.0、28.0、28.2 dBi,固定点波束在服务区EOC gain不低于34 dBi并且在0~6.5°范围内的扫描波束增益不低于35 dBi。

To meet the requirement of multiple tasks in parallel in spaceborne communication,this paper proposes a common aperture multi-beam reflector antenna composed of a Gregorian reflector and three feed-horn antennas,which can generate two contoured beams and one spot beam.The antenna is designed using ray tracing method to determine the optimal spot beam feed position for establishing the antenna infrastructure,and employing Zernike polynomials and cubic B-splines function to optimize the shape of both the main and secondary reflectors.To validate the efficacy of the method,simulation experiments were conducted on 1.1 m diameter antenna.The results demonstrate that the edge of coverage gain for both shaped contour beams in Ku receiving and transmitting bands are 27.7 dBi,28.0 dBi,28.0 dBi and 28.2 dBi,respectively.The spot beam exhibits a minimum service EOC gain of not less than 34 dBi,while the scanning beam gain within the range of 0 to 6.5°is not less than 35 dBi.