Evaluation of a Calorimetric Thermal Voltage Converter for RF–DC Difference up to 1 GHz

Abstract

In this paper, we present a performance evaluation of the RF-DC transfer difference for a calorimetric thermal voltage converter (CTVC) designed by the National Research Council of Canada (NRC) at frequencies up to 1 GHz. In the first part of this paper, we describe a bilateral comparison of the RF-DC difference standards between the NRC and the National Metrology Centre of the Agency for Science, Technology and Research of Singapore, in the frequency band from 1 kHz to 100 MHz. A good agreement is observed between the two laboratories using the CTVC as a traveling standard. In the second part of this paper, we evaluate the performance of the CTVC at higher frequencies up to 1 GHz. In this part, RF-DC difference of the CTVC is mathematically modeled and experimentally evaluated in terms of the calibration factor of a thermistor mount and the reflection coefficients at its type-N input connector.Index Terms-AC-DC difference, calorimetric thermal voltage converter (CTVC), mathematical modeling, RF-DC difference.

Linearity analysis of a calorimetric thermal voltage converter for RF-DC transfer difference up to 1 GHz

“…The CTVC was evaluated in terms of the calibration factor of a NRV-Z51 power sensor and the reflection coefficients at its input connector with a newly proposed calibration model [4].…”

“…Derivation details of (2) can be found in [4] In the following, the linearity of a NRC CTVC will be evaluated using the proposed mathematical model (2) with the input voltage of 0.71 V, 1 V and 2 V in the frequency range of 50 MHz to 1 GHz.…”

“…Recently, the National Metrology Centre (NMC) of the Agency for Science, Technology and Research (A*STAR), Singapore has worked together with the NRC to evaluate the performance of a CTVC up to 1 GHz [4]; firstly a bilateral comparison of the HF (1 kHz -100 MHz) RF-DC voltage transfer difference, and secondly a preliminary evaluation of the NRC CTVC up to 1 GHz. Good performance has been observed.…”

Computation of the Characteristic Parameters of Coaxial Waveguides Used in Precision Sensors

“…Cylindrical coaxial waveguides and cables are currently used in many different applications, from antenna feeders to high-precision wideband measuring instruments, sensors and standards [ 1 , 2 , 3 , 4 , 5 ]. These include calculable thermal converters used in voltage AC-DC transfer [ 6 , 7 ], which usually require a multilayer coaxial waveguide to feed the microwave heater fixed to the multijunction thermocouple. An example of a precision sensor used in the voltage standard that requires a coaxial multilayer waveguide can be found in [ 8 ].…”

International Journal of Electronics and Telecommunications

“…ultilayer cylindrical waveguides are used in highprecision wideband measuring instruments and standards, including calculable thermal converters used in voltage AC-DC transfer [1], [2] and precision high frequency current shunts [3]- [5]. Characteristic impedance of waveguides used in abovementioned metrology instruments must be calculated with a very high accuracy, achieving parts per million.…”