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Fundamental Guided Wave Metrology


Radio-frequency (RF) waves and microwaves are involved with almost every facet of everyday life. Radio stations, television, wireless devices, satellite services, weather radar, and many more use RF/microwave signals. Making sure that all of these devices and the signals they utilize work properly and have minimal interference with other devices is critical. A set of basic measurement capabilities and standards are necessary to support the users of RF/microwave devices. The Fundamental Guided Wave Metrology Program develops and maintains the U.S. national standards for RF and microwave quantities, providing a wide range of state-of-the-art calibration services and developing new measurement methods and verification techniques to improve the measurement of microwave quantities. The program is focused on fundamental measurement research for microwave parameters. Customer-oriented services are a natural outgrowth of this research-focused effort.


Probe station for making automated on-wafer device measurements.

The science of microwave measurements is expanding in many different directions. There is a constant push to use higher frequencies. Signals are becoming much more complex and include modulation effects, multiport/differential signals, complex waveforms, and other unusual signal schemes. On-wafer measurements are in greater demand. These new requirements are dictated by the needs of the telecommunication, computing, defense, and general electronics communities. Our work looks at the fundamental metrology problems for thermal noise, scattering-parameter, power, and waveform measurements. We provide a large range of state-of-the-art microwave measurements, theoretical developments, techniques, and standards for customers. We cover from 100 kilohertz to above 110 gigahertz through many different microwave connector sizes.

Our customers for the measurement services come from a broad cut of the electronics industry. These customers generally use our measurements to support their internal calibration processes. This includes establishing their traceability chain, support for accreditation, calibration standards, and verification of their systems. The end uses may be anything from satellite systems to weapon or other military systems, computer chips, cell phones, or microwave ovens. One recent example is a calibration for the Food and Drug Administration (FDA) to support its microwave oven standards. We are transforming our services to better meet the needs of our customers. We are developing a strategy for moving the measurement services into the future and are developing improved methods for delivering our services. The main cornerstone of this approach is a strong research and development program in these areas. The measurement services are a natural outcome of our focus on the research of the fundamental metrology that underlies the measurement capabilities.

Major Accomplishments

  • Completed and evaluated a new WR-15 calorimeter for power measurements.
  • Completed a 1.85 millimeter direct comparison power system and uncertainty analysis. 
  • Extended s-parameter capabilities to 1.85 millimeter connectors with uncertainty analysis.
  • Constructed and tested 400 gigahertz electro-optic sampling system.
  • Terminated the classic artifact based s-parameter measurement services (these are being replaced with a measurement comparison approach.)

Associated Publications/Reports:

  • A. Lewandowski, D. Williams, "Characterization and Modeling of Random Vector Network Analyzer Measurement Errors," 17th International Conference on Microwaves, Radar and Wireless Communications (MIKON) (Warsaw, Poland), pp. 1-4, May 2008.
  • J. P. Randa, D. K. Walker, "On-Wafer Measurement of Transistor Noise Parameters at NIST," IEEE Transactions on Instrumentation and Measurement, vol. 56, pp. 551-554, April 2007.
  • D. Gu, D. Walker, J. P. Randa, "Noise-Parameter Measurement with Automated Variable Terminations," Conference on Precision Electromagnetic Measurements (CPEM) (Broomfield, CO), June 2008.

Created December 2, 2008, Updated August 31, 2016