多子阵平板天线波束指向频率响应分析与固定长度延迟线应用

摘要

As the application of SATCOM On-The-Move (SOTM) is restricted by the height of antenna, the planar antenna with multiple subarrays is adopted to reduce the height of antenna. However, the excursion of beam pointing versus frequency is deteriorated because of its dispersed aperture. In order to reduce the excursion of beam pointing, the feeder system using fixed delay line and phase shifter is applied in this paper, and the switching-beam technique based on multi-set fixed delay lines is proposed. The proposed method divides the antenna scanning range into several small ones, and uses different fixed delay lines in each range. Simulation results show that the method can reduce the excursion of beam pointing effectively, and the requirement of beam pointing accuracy for SOTM can be satisfied.%天线高度是宽带卫星移动通信系统推广应用的一个重要制约因素,采用多子阵技术可以降低平板天线的天线高度.然而多子阵平板天线阵的离散口径会造成天线波束指向频率响应的恶化.为改善天线波束指向频率响应,该文采用固定长度延迟线与移相器相结合的两级馈相方法,提出了一种基于多套延迟线的切换波束技术,将天线波束的扫描范围划分为多个区域,各区域采用不同的延迟线以合成相应的波束.仿真结果表明,该方法可以有效减小天线波束指向漂移,满足卫星移动通信系统对天线波束指向精度的要求.