Development of a Large-Signal-Network-Analyzer Round-Robin Artifact

This article presents the design and measurement results of the contest-winning LSNA round-robin artifact. The proposed two-port device was designed with respect to the objective of complementing an upcoming LSNA international round-robin between measurement facilities. The proposed device consists of three parts, a nonlinear circuit generating the required five harmonics based on a monolithic InGaP HBT MMIC amplifier, an output circuits based on a wideband amplifier and attenuator, which role is to amplify the signal generated by the nonlinear device and isolate the nonlinear device from the output load, and finally, a stabilized dc supply circuit based on voltage regulator chips typically used for instrumentation. To avoid noise interfering with the measurement, EMI considerations were taken into account. The overall device is shielded within a casing composed of three cavities to isolate each circuit. This casing also helps as a heat sink to stabilize the artifact in temperature. The proposed device is validated by measurements. Thanks to a high output signal level at the fundamental and harmonics, a high-value attenuator can be used to efficiently isolate the artifact from the load and still obtain a sufficiently high output signal for accurate measurement with an LSNA.