基于波束分离技术的空间时延补偿方法研究

Research on Space Time Delay Compensation Method Based on Beam Squint Technique

针对深空测控通信任务中,空间时延和地球自转使大型地面天线窄波束不能覆盖对应的轨道区域导致的通信链路质量恶化甚至中断的问题,提出了在波束波导馈电的多反射面天线中,通过改变收发馈源位置使上下行波束峰值分离并指向不同的位置实时改善通信链路质量的方法,给出了波束波导馈电系统中馈源位置与波束分离以及增益损失的关系。该方法可以准确地预计并通过改变上行发射馈源的相对位置,使上下行波束按照要求指向不同的位置以减小天线上行链路增益损失。以35 m深空测控通信天线为例进行仿真,在Ka波段34 GHz频率,当上下行链路波束分离达0.032 72°时,增益损失小于4.25 d B。该方法也可用于确定馈源的位移量来修正由于反射面天线结构变形或复杂的多反射面系统镜面位置误差等造成的天线波束误差。

In deep space TT＆C mission, the space time delay and Earth rotation make the narrow beam of large ground antennas unable to cover the corresponding orbit area, which leads to the quality deterioration or even interruption of the communication link. A technique for a real-time beam separation correction scheme for deep space uplink and downlink communications is presented, which provides a close relationship between the beam squint angles and the corresponding feed displacement for a reflector antenna with abeam waveguide （BWG） or multiple reflector system. The simulation results of 35-meter antenna at Ka band （ 34 GHz） show that the uplink beam gain loss is less than 4.25 dB by moving the uplink feed position when the up/downlink beam separation angle is 0.032 72 o. It is also useful to determine the feed ofl%et position to correct the beam deviation caused by the imperfect antenna mechanical structure and the mirror misalignments of the complex multiple reflector system.