Vector-corrected nonlinear multi-port IQ-mixer characterization using modulated signals

This work reports on a wideband (WB) measurement system based on a vector network analyzer (VNA) topology for multi-port large-signal measurements. The setup exploits a modified commercial VNA with WB intermediate frequency (IF) outputs that allows for more than 5 GHz analysis bandwidth (BW), where the IF is captured using an external high-speed oscilloscope. A three-port configuration using six receivers is described, together with the signal processing to achieve the high dynamic range required for WB signal measurements. The calibration procedure to establish reference planes at the three ports of the device-under-test (DUT) are shown. A comparison is made between single-tone continuous-wave (CW) calibration and WB calibration using multi-tone signals, illustrating advantages, challenges and limitations. The system is then demonstrated for on-wafer WB characterization and linearization of a Dual Input Doherty Power Amplifier (DIDPA) using a 100-MHz instantaneous BW excitation signal at millimeter-wave frequencies. By leveraging on the error-corrected WB waves, an algorithm is proposed for modulated input signal control across a 600-MHz acquisition BW at the DUT on-wafer reference planes. The algorithm enables a user-defined emulated splitting of the input WB signals. The linearization performance of such an emulated PA configuration is finally evaluated.Index Terms-Digital predistortion (DPD), doherty power amplifier (DPA), millimeter-wave measurements, vector network analyzer (VNA), wideband measurements. I. INTRODUCTIONM ODERN applications of wireless telecommunications, as well as radar, exploit modulated signals at millimeter-wave frequencies with increasingly wider bandwidths (BWs), in the range of hundreds of MHz and beyond. Components and subsystems are therefore required to operate across large instantaneous BWs, so that instrumentation and characterization features need to be adapted to this demanding scenario. Nonlinear devices, such as radio-frequency (RF) power amplifiers (PAs), require network analysis to extract figures-of-merit (FoMs) like input and output match, available power gain, load-pull contours, etc. At the same time, they also require signal analysis FoMs like the error vector magnitude (EVM) [1]. As an additional complication, modern PA topologies addressing the ever-demanding trade-off between broadband linearity and power efficiency often result This work was partly funded by the German Federal Ministry of Education and Research (BMBF) under the project reference 16FMD02 (Forschungsfabrik Mikroelektronik Deutschland). C. Schulze, W. Heinrich and O. Bengtsson are with Ferdinand-Braun-Institut, Leibniz-Institut fuer Hoechstfrequenztechnik, Gustav-Kirchhoff-Str.

show abstract

Vector-corrected nonlinear multi-port IQ-mixer characterization using modulated signals

Cited by 3 publications

References 6 publications

A fully calibrated NVNA set-up for linearity characterization of RF power devices using Unequally Spaced Multi-Tone signal through IM3 & IM5 measurements

A fully calibrated NVNA set-up for linearity characterization of RF power devices using Unequally Spaced Multi-Tone signal through IM3 & IM5 measurements

VNA-Based Characterization of Frequency Multipliers Phase-Distortions Under Continuous-Wave and Modulated Signal Excitation

A VNA-Based Wideband Measurement System for Large-Signal Characterization of Multiport Circuits

Contact Info

Product

Resources

About