A microcalorimeter and bolometer transfer standard are used as a national standard for microwave power from 50 MHz to 50 GHz. the microcalorimeter is used to determine the efficiency of the bolometric transfer standards and is similar to an existing Type N coaxial microcalorimeter at NIST. The transfer standards are dc substitution power detectors with two resistors on a small integrated circuit that are tightly thermally coupled. One resistor terminates the coaxial input and dissipates the RF power while the other resistor dissipates DC power. The first resistor is temperature insensitive and approximately 50W while the second resistor (which has a positive temperature coefficient) is about 1000W and acts as the bolometer element. A power supply maintains the bolometer element at constant resistance. Typical calorimeter data is shown and future plans for development will be briefly discussed.
Conference Dates: November 6-8, 2001
Conference Location: Harrogate, UK
Conference Title: 2001 British Electromagnetics Conference
Pub Type: Conferences
2.4 mm coaxial, bolometer, calorimetry, metrology, microcalorimeter, microwave