FIG. 6.

Example of the nonlinear admittance estimation from measurements. (a) Measured mixing product, $\hat{b}\left({\omega }_1+{\omega }_2\right)$ of a CPW of length $1.340\mathrm{m}\mathrm{m}.{\omega }_2=2\pi \times 5\mathrm{G}\mathrm{H}\mathrm{z}$. (b) ${\hat{b}}_{\text{model}}\left({\omega }_1+\left.{\omega }_2\right)\right.$, the hypothetical value of the mixing product under the condition ${\hat{Y}}^{\left(2\right)}\left({\omega }_1,{\omega }_2\right)=1$. The estimated uncertainty in (b) from uncertainty in ${\hat{Y}}^{\left(1\right)}$ is smaller than the width of the line. (c) ${\hat{Y}}^{\left(2\right)}\left({\omega }_1,{\omega }_2\right)$ estimated by ${\hat{Y}}^{\left(2\right)}\left({\omega }_1,{\omega }_2\right)=\hat{b}\left({\omega }_1+\left.{\omega }_2\right)/{\hat{b}}_{\text{model}}\left({\omega }_1+{\omega }_2\right)\right.$. Error bars in (a) and (c) represent a 95% confidence interval estimated from the distribution of ${\hat{Y}}^{\left(2\right)}$ estimates from CPWs of different lengths. We omit error bars on individual data points for visual clarity.