Uncertainty Evaluation of a Broadband Attenuation Standard.

A standard step attenuator has been developed. It comprises a build-up chain of ten steps of power ratio measurement and operates in a frequency range of 10 MHz to 18 GHz. The overall system has a dynamic range of 90 dB and an expanded uncertainty of 0.006 dB (k = 2). The system is used as an attenuation standard in a series radio-frequency substitution scheme. The uncertainty factors in the attenuation measurement of 40 dB at S GHz are fully described. For the calibration of a typical step attenuator, the expanded uncertainties are 0.011 dB for the attenuation range up to 80 dB, including the mismatch uncertainty. [ABSTRACT FROM AUTHOR]