A Rigorous Analysis of the Random Noise in Reflection Coefficients Synthesized via Mixed-Signal Active Tuners

In this contribution, we present a rigorous analysis based on uncertainty propagation techniques to estimate the random variation of the controlled reflection coefficient in mixed-signal load-pull test benches. A digital-to-analog converter is commonly used in these test benches to generate the baseband signal required to synthesize the high-frequency, user-defined injected wave. To study the random noise of the injected wave, which can be mapped to the noise of the controlled reflection coefficient, we employ Jacobian sensitivity functions between the baseband signal and the RF one. First, the baseband integrated rms noise of the up-converter is evaluated, and then the upconverted noise is determined via the derived transfer function. Finally, experimental results to validate the uncertainty control bound of the synthesized reflection coefficients are presented, highlighting a full coverage of the measured reflection coefficients.