【摘要】 介绍了噪声系数分析仪对噪声系数这一关键参数校准的改进方法。由于噪声系数的技术指标很高，要求达±0.05 dB，在校准时必须减少端口失配所引入的测量不确定度。在JJF 1460—2014中，通过在步进衰减器两端加隔离器来减少端口失配所引入的不确定度。经过分析，认为在无隔离器的实验室中，通过在步进衰减器两端各增加一个约10 dB的精密固定衰减器，同样可以达到与隔离器相同的校准能力。根据试验数据给出了校准结果的分析以及相应的不确定度评定结果。更多还原

【Abstract】 There is a new improved approach to calibration specification for noise figure, which is much important for the noise figure analyzers.Especially good noise figure shall be within ±0.05 dB so that it is necessary for the noise figure measurement accuracy to minimize mismatch uncertainties. According to the JJF 1460—2014 the insulators have been replaced by precise attenuators based on the method of step attenuator. It’s clear from the analyze that using 10 d B precise attenuators could have the similar calibration capability in the laboratory without insulators. With the result of experiment, The evaluation of uncertainty measurement has been reviewed.更多还原