Development of a type-N coaxial microcalorimeter for RF and microwave power standards at KRISS

Sets of coaxial and waveguide microcalorimeters have been successfully used as primary power standards in RF and microwave frequency ranges at KRISS. Recently, we have developed a type-N coaxial microcalorimeter to replace a legacy microcalorimeter that had been in use for over two decades. Design of some core parts and implementation of the microcalorimeter are described. Preliminary uncorrected effective efficiencies of type-N coaxial reference standards are shown, and future plan for system evaluation is briefly discussed.