Joel Dunsmore

Joel Dunsmore is a Keysight R&D Fellow working at the Santa Rosa Site. He received his Ph.D. from Leeds University in 2004. He was a principal contributor to PNA family of network analyzers, with recent work in non-linear test, including differential devices, and mixer measurements, as well as modulated and spectrum measurements. He has received 36 patents and authored the “Handbook of Microwave Component Measurements, 2nd Edition (John Wiley, 2020)”, and has the YouTube Channel @DrJoelVNA, email at jdunsmore@gmail.com

Modern Vector Network Analyzers (VNA) have flexible hardware and software with much higher performance than VNAs of even a few years ago. There are a wide range of measurement applications, beyond simple S-parameters, that a VNA can address, and with precision that cannot be achieved by other test methods. VNAs now act as a multi-functional test system, providing an extremely wide range of device- and signal-characterization capabilities including noise figure, gain-compression, true-mode differential device characterization, two-tone Inter-Modulation Distortion (IMD), phase-noise, mixer and frequency converter gain/phase/delay measurements.  Very recently Vector Spectrum Analysis (VSA) capabilities have been added, including measurements of complex modulated signals such as Error Vector Magnitude (EVM), Adjacent Channel Power Ratio (ACPR) and characteristics of Digital Pre-Distortion (DPD). These capabilities, when properly configured, provide the most precise measurements of high-frequency mm-wave and sub-THz modulated signals, beyond the capabilities of stand-alone measurement instruments, as will be demonstrated using 20 GHz bandwidth modulated signals at 250 GHz. This lecture illuminates the methods and capabilities for these advanced measurement methods for characterizing microwave components.