Realization of a calculable RF power standard in coplanar technology on alumina substrate

This paper presents the first efforts toward a calculable power standard in the RF domain based on a modeling approach. Consequently, it could be possible to theoretically determine the input reflection coefficient and the efficiency of the power detector. We simulated and realized a coplanar thermistor mount prototype in the 50-MHz8-GHz frequency range whose performance has been validated by measurements. The maximum deviations between simulated and measured values do not exceed 0.06 for the reflection coefficient. The mean relative error between the measured and computed efficiency is about 1.2% over the whole frequency band. Finally, the input reflection coefficient is less than 15 dB and the efficiency is greater than 0.90 in the 50-MHz7-GHz frequency range.