Rohde & Schwarz is stepping in to close that gap with its new R&S NTS thermoelectric RF power transfer standards.
For decades, the metrology world relied on thermistor mount standards to traceably measure RF power. It was a proven method, but it hit a dead end, manufacturers stopped building them years ago, leaving calibration labs stranded without replacement parts or support for emerging high-frequency ranges like the D-band.
Rohde & Schwarz is stepping in to close that gap with its new R&S NTS thermoelectric RF power transfer standards. Built explicitly as a high-performance, drop-in replacement for those obsolete thermistor mounts, the NTS family brings traceable RF power measurements back to the highest metrological level.
With a purely passive, analog architecture, these sensors are engineered to serve as both primary standards in microcalorimeters and as transfer standards for national metrology institutes (NMIs), accredited calibration labs, and demanding industrial environments where regulatory compliance and product quality require absolute measurement certainty.
A Seamless Upgrade Path
One of the biggest hurdles in metrology is replacing legacy equipment without tearing up established workflows.
The R&S NTS side-steps this beautifully. Its compact form factor drops straight into existing microcalorimeter setups without the need for bulky new base units.
The sensors interface directly with the traceably calibrated DC nanovoltmeters labs already own, and Rohde & Schwarz is supplying dedicated software to smooth the transition from old thermistor setups to modern thermoelectric tech.
Metrology-Grade Thermoelectric Tech
At the heart of the NTS is a proprietary thermoelectric power detector chip engineered specifically for metrological RF-DC substitution.
It builds on two decades of pedigree from the company’s NRP power sensors, dialed up for extreme accuracy.
The transducer uses two highly symmetrical RF and DC heaters to achieve near-perfect RF-DC substitution. This optimized design delivers incredible linearity, cutting the operating-point influence on the calibration factor down to the PPM-per-milliwatt range.
Throw in excellent impedance matching, a dead-flat frequency response, fast settling times, and a high maximum input power of +20 dBm, and you have a tool built for the rigors of precision calibration.
Rohde & Schwarz sweated the details here. The design includes a 4-wire DC heater connection for ultra-precise power substitution, low-impedance DC lines to strip out parasitic heating losses, and an onboard temperature sensor to offset microscopic thermal drift.
Covering the Spectrum
At launch, the NTS family rolls out with multiple coaxial models covering DC to 67 GHz, plus a WR 6.5 waveguide model pushing all the way to 170 GHz.
They are also offering specialized open, short, and mismatched variants to help labs pin down microcalorimeter correction factors.
By pairing the NTS transfer standards with their NRPC calibration solutions, NRP power sensors, and signal generators, Rohde & Schwarz has effectively built a complete, in-house ecosystem for traceable RF power calibration from end to end.
For further information visit: https://www.rohde-schwarz.com/product/nts
