The big picture
Developing next-generation 5G mobile wireless communication systems will require advances in transistor performance and new hardware capable of operating in the millimeter wavelengths of tens to hundreds of gigahertz. These large-signal semiconductors will operate at high power, which introduces serious measurement complexity – and presents a fundamental challenge to a wireless industry that aims to design equipment operating in the millimeter-wave.
That measurement complexity stems in large part from high-power mmWave semiconductors behaving in nonlinear ways. In particular, they tend to generate collateral frequencies. For example, transistors producing 30 GHz signal also kick off signals double and triple that resonance – the second and third harmonics. While that sounds sound musical enough, harmonics sap precious battery power and are ultimately noise. Millimeter-wave harmonics need to be characterized to the point system designers can minimize them. NIST CTL is developing the measurement capabilities to deal with nonlinear transistors and other devices, something not possible with conventional instruments such as vector network analyzers.
What we do
Commercial large-signal network analyzers (LSNAs) available at mmWave frequencies are often un-calibrated and generally untraceable. NIST CTL is providing the metrological basis for large-signal network analysis at mmWave frequencies and is working to apply mmWave LSNA technology to industrial problems and traceability at these frequencies.
For more detail on specific research initiatives related to this NIST CTL program, please see our Transistor and Other Nonlinear Device Measurement R&D topics.
Transistor and Other Nonlinear Device Measurement
The big picture