CENAM's primary standard for microwave power up to 18 GHz

This paper describes the development of a type-N coaxial microcalorimeter and its associated transfer standard, which together are now used as the Mexican Primary Standard for Microwave Power from 0.05 GHz to 18 GHz. The comparison method used to evaluate the microcalorimeter correction factor is presented, and the calibration results for the effective efficiency of the transfer standard are shown and compared against NIST measurements. Finally, a locally developed data acquisition system, with a software leveling loop, used to automate the effective efficiency measurements is briefly discussed.