Shape error study of inflatable antennas using a numerical model

We conduct an in-depth study on the shape error of initially curved antennas to investigate errors that occur in the design and manufacturing processes. First, a numerical model is developed to simulate the actual surfaces. This model features a main advantage that it can predict the effects of cutting patterns on the shape error. The model is used to evaluate and optimize the design of cutting patterns. An error sensitivity analysis is performed to quantify and distinguish between the effects of error sources in manufacturing. The following sources are analyzed: errors in the elastic modulus of the membrane, pressure variations, and boundary deviations. The boundary deviation is found to be the most significant error source, and thus, boundary perturbation is recommended as an efficient error control measure. Finally, an inflatable antenna model is used to experimentally validate the numerical model. The experimental results display acceptable agreement with the numerical results. Thus, the developed numerical model and error control measure are shown to be feasible and efficient.     

星载缝隙波导微波天线热控方案研究与验证

微波天线阵面的热变形是影响在轨指向精度的关键因素,如何解决大功率器件的散热问题至关重要。某微波天线热耗峰值近万瓦,在近20 m²的全阵面内,需要保证收发(TR)组件的温升和补偿加热器的功耗不能过高。针对某微波天线特有的工作模式和外热流情况,提出了机械泵驱动流体回路(MPFL)、双面散热和相变热管 3种热控方案,并分析了各自的特点和适用性。为解决天线内部狭小空间的辐射传导耦合问题,开展了单模块热阻实验分析与优化,并得到了在轨测试的验证。     

宽波束赋形天线星地测试技术分析与改进

为满足风云三号 G星长寿命、高可靠、业务化的工作要求,星上数传天线采用通信性能好、覆盖率高的宽波束赋形设计。但宽波束赋形天线测试技术相对复杂,对测试质量有潜在影响。文章重点阐述了风云三号 G星数传天线设计方案的必要性,建立星地链路余量分析,对星载数传天线的仿真和试验结果比对进行分析,验证了天线方向图测试结果的有效性,并对星载天线和地面系统的测试技术提出改进,提高了测试结果的准确性和完整性。相应技术的改进可以为平台方案相近的空间辐射测量基准卫星平台系统综合试验验证技术提供支撑。     

Type synthesis of deployable mechanisms for ring truss antenna based on constraint-synthesis method

Space deployable antenna is the key equipment in realizing the communication and data transmission between the spacecraft and the earth. In order to enrich the configurations of deployable antennas, the type synthesis of deployable mechanisms for ring truss antenna is conducted in this study. First, the principle of the constraint-synthesis method based on screw theory is briefly described, the structure of the ring truss deployable antenna and its folding principle are analyzed, and the ring truss mechanism is divided into upper edges, lower edges and linkages. Then, based on the constraint-synthesis method, the type synthesis of the basic unit edges is carried out, a series of basic unit mechanisms are obtained from combining the basic unit edge mechanisms, and five mechanism units with fewer joints and simple structures are selected. Furthermore, simulation models of the five ring truss deployable mechanisms are built in Solidworks and Matlab software, and the deploying process is verified by the movement simulation. Finally, mechanism characteristics of the five mechanisms are analyzed and discussed, and a prototype is manufactured, verifying the analysis in this paper. This research provides a new way for the type synthesis of spatial deployable mechanisms, and the ring truss deployable mechanisms obtained in this study can be well applied in the field of aerospace.     

含多间隙柔性可展帆板动力学建模及仿真

为研究柔性和多级铰链间隙对帆板展开过程动力学特性的影响，以月球车两级往复可展太阳帆板为研究对象，采用修正Coulomb模型表述摩擦力，通过接触碰撞力描述间隙，运用有限元法进行帆板柔性化，进而建立多间隙-柔性耦合的动力学模型。采用变步长伦哥库塔法进行数值求解，模拟帆板展开过程，分析了多间隙和柔性对帆板质心加速度、铰链间隙碰撞力等参数的影响。结果表明，在保证展开机构刚度要求的前提下，帆板柔性可补偿因铰间隙引起的加速度波动，减弱间隙处碰撞的剧烈程度，减小碰撞力幅值，进而改善帆板展开机构的动态特性。研究结果可用于指导月球车两级往复可展太阳帆板等同类型的可展机构动态优化设计。     

航天器可展SAR天线结构综述

论述了航天器径向肋式、缠绕肋式、构架式和环形桁架式四种抛物面可展SAR天线结构的研究现状,分析了四种抛物面可展SAR天线结构的特点,分别对航天器翼式、桁架式和薄膜式三种平面可展SAR天线结构进行了综述,指出了航天器可展SAR天线结构轻质、大收纳比和高精度的发展趋势,提出了航天器可展SAR天线实现展开高精度需攻克的关键技术,旨在为航天器可展SAR天线结构的创新发展提供参考。     

关于信息对抗中的“近空间”飞行器共形天线的探讨

文章首先从现代战争作战方式为立体空间、整体作战开始论述了发展“近空间”飞行器的必要性;然后对适合于“近空间”飞行器的天线作了综述,指出了采用共形天线将带来的好处,并给出了能够应用于共形天线的单元型式,重点探讨了微带线作为共形天线单元的优点,再针对导航信息对抗提出了一种与飞艇共形的天线方案构想;最后给出了共形天线将是未来发展的一个重要方向的结论。     

一种新的单通道阵列DOA估计快速算法

针对现有单通道阵列DOA估计算法复杂度较高、实时性较差的问题,提出一种适用于单通道阵列的快速DOA估计算法.该算法将常规多通道阵列的空间FFT算法引入单通道阵列信号处理中,将通道切换时间带入FFT运算中,构建了新的变换核函数,利用该核函数可直接对单通道阵列的采样信号进行空间FFT变换,基于此提出了适用于单通道阵列的SA...     

一种基于移相插值方法的相控阵列天线波束形成网络

文章提出了一种移相插值网络方法,可以有效降低大型相控阵列天线馈电网络的复杂性;然后基于该方法设计了一种相控阵列天线的波束形成网络;最后对13单元的一维线性阵列和19单元的面阵进行了仿真,仿真结果验证了该方法的有效性。     

星载GPS天线相位中心偏差对定位精度影响的试验方法研究

介绍星载GPS天线相位中心偏差的概念,简要分析GPS天线相位中心变化对GPS定位精度的影响,并建立相应的数学模型。利用已有的多台星载GPS天线、载波相位测量方式的星载GPS接收机,进行GPS天线相位中心偏差测试以及接收机绝对定位精度、相对定位精度测试,测量、统计天线相位中心偏差与GPS接收机绝对定位精度和相对定位精度的对应数据,对误差模型进行验证。