30MHz大衰减(60dB,100dB)的国际比对

An International Comparison of High Attenuation (60dB,100dB) at 30MHz

频率30MHz、衰减量高达100dB的大衰减国际比对已经完成,共有12个国家计量机构参加,传递标准是标称值分别为60dB和100dB的两个固定衰减器和标称值为100dB的一个开关衰减器。比对结果是:60dB衰减量的最大差值为0.064dB,100dB衰减量的最大差值为0.125dB。其中,有5个实验室的测量平均值彼此偏离在60dB量程时不大于0.001dB,在100dB量程时不大于0.005dB。我国的数据正处于这5个实验室数据的中间(100dB时)。

GT-RF 78-1 is the first world-wide comparison program of national standard devices in which high attenuation values up to 100dB at the frequency of 30MHz have been compared.Twelve national laboratories of metrology participated.The transfer standards were two fixed attenuators with a nominal attenuation of 60dB and 100dB respectively and one switchable attenuator of 100dB.The maximum difference between any two results is 0.064dB at 60dB and 0.125dB at 100dB.For five laboratories,the deviation between their mean values was not larger than 0.001dB for a 60dB attenuation step and not larger than 0.005dB for a 100dB attenuation step.The mean value of NIM located at the middle of the mean values of these five laboratories at 100dB.