摘要
介绍了中国计量科学研究院(NIM)开发的一套精密球面近场扫描法天线校准装置(400 MHz^110 GHz)在测量天线归一化方向图(限于幅度)时的不确定度评定。以"自我比较法"为基础,简介了探头、安装对准、数据采样和射频系统等引入的18个不确定度分量的评定结果,重点针对天线暗室反射引入的不确定度不易评估的难题,基于射线追踪法提出了一种分析、测量和计算相结合的"干扰法"。评估结果表明该套近场系统在-40dB副瓣电平内,重复性优于0.1 dB(26 GHz)、在忽略探头极化误差时的扩展不确定度优于2.7 dB。最后分析了球面近场天线测量的不确定度特点。
Some research is made for the uncertainty of normalized antenna radiation pattern （only amplitude） from NIM precise spherical near-field （SNF） antenna measurement facility （400 MHz to 110 GHz）. There are 18 uncertainty items from probe, mounting, data sampling and radio-frequency system are introduced in brief, based on ＂self-comparison approach＂. A detail ＂perturbation method＂ is proposed to evaluate the scattering from the anechoic chamber based on the ray-tracing method; it is known that sometimes it is impossible to move the spherical system in the anechoic chamber to evaluate the scattering from the absorber. The evaluation results show that for NIM＇ s SNF facility, when the side lobe up to -40 dB, the repeatability is less than 0. 1 dB （26GHz） , and the expanded uncertainty for a normalized radiation pattern （amplitude） is 2.7 dB when ignoring the cross-polarization of the probe. Finally, the uncertainty characteristics of a SNF facility is summarized.
出处
《计量学报》
CSCD
北大核心
2017年第6期758-762,共5页
Acta Metrologica Sinica
关键词
计量学
球面近场
干扰法
不确定度评定
天线方向图
metrology
spherical near-field
perturbation method
uncertainty evaluation
antenna radiation pattern
