ABSTRACT

As one source type of random surface errors, misalignment errors usually lead to petal rigid body rotation or translation for petal-type deployable reflectors, which deteriorate petal-type surface from its ideal parabolic shape. To evaluate the effects of misalignment errors on antenna performance, a novel method is proposed to reveal the degradation of petal misalignment errors on average radiation pattern for petal-type deployable reflectors. Based on coordinate transformations, the surface deviation from ideal parabolic shape caused by petal misalignment errors is introduced into an explicit far-field formula, which promotes the far-field formula as explicit functions of petal misalignment displacements in this novel method. By assuming Gaussian distribution of misalignment errors, the average radiation patterns with varying standard deviations of petal misalignment errors are obtained. Compared with the existing methods of random error characterisation, the effectiveness of the proposed method is verified. Simulations show that among the petal misalignment errors, both the petal rigid body rotation around hinge link axis and translation along boresight direction provide deterioration effects on antenna radiation pattern, and the proposed method can provide design guidelines for hinge structural design.

摘要

作为随机表面误差的一种来源类型，失准误差通常会导致花瓣型可展开反射器的花瓣刚体旋转或平移，从而使花瓣型表面偏离其理想的抛物线形状。为了评估失准误差对天线性能的影响，提出了一种新方法来揭示花瓣失准误差对花瓣型可展开反射器平均辐射方向图的影响。基于坐标变换，将由花瓣未对准误差引起的表面与理想抛物线形状的偏差引入到显式远场公式中，从而将远场公式提升为该新方法中花瓣未对准位移的显式函数。通过假设不对中误差的高斯分布，获得了具有不同花瓣未对准误差标准差的平均辐射方向图。与现有的随机误差表征方法相比，验证了该方法的有效性。仿真结果表明，在花瓣未对准误差中，花瓣刚体绕铰链连杆轴旋转和平移视轴方向都会对天线辐射方向图产生恶化影响，所提出的方法可以为铰链结构设计提供设计指导。