Comprehensive analysis of small signal equivalent circuit models for GaAs-based PIN diodes is performed in this paper. The analysis provides the equivalent circuit models for PIN diode operation in four different operation modes. A compact nonlinear equivalent circuit model has been developed which takes into account the DC/AC frequency dispersion of the diode dynamic resistance. In order to verify the validity of the proposed circuit model, the comparison between the modeled and measurement data is given, good fitting is obtained for GaAs-based PIN diode.

An improved millimeter-wave nonlinear model for InP heterojunction bipolar transistor (HBT) is proposed in this letter. The frequency dispersion effect has been taken into account in the Agilent HBT model in Agilent ADS software. Model verification is carried out by comparison of measured and simulated dc and S-parameters up to 110 GHz.

Scalable modeling and parameter extraction of the millimeter wave GaAs-based PIN diode for W-band switch design are presented in this paper. A direct-extraction method based on the S-parameters on wafer measurement is utilized to determine the extrinsic and intrinsic model parameters without any de-embedding test structures. Under turn-on and turn-off biased conditions, the modeled input reflection coefficients agree well with the measured data in the entire frequency ranges for GaAs-based PIN diode. The scalable normalization rules have been used to design W-band PIN diode switch successfully, good agreements are obtained between simulated and measured data to verify the accuracy of the proposed model.

A compact scalable large signal model for GaAs Schottky diodes including edge effect and dc/ac dispersion is proposed in this article. The scalable rules for extrinsic resistance and intrinsic model parameters are given in detail. The experimental and theoretical results show that at the same bias condition, good scaling model parameters can be achieved between the diodes with different anode equivalent junction areas. Good scaling of the large signal model parameters can be achieved between the large-size devices and elementary cell. Model verification is carried out by the comparison of measured and simulated dc and S-parameters for two diodes with different sizes in parallel up to 170 GHz.

An improved scalable large-signal model for gallium nitride high-electron-mobility transistors (GaN HEMTs) based on the EEHEMT model is proposed. The derived DC model can accurately predict the current-voltage behavior including the kink effect over a wide range of bias points by introducing the parameter $V_{\textrm{kink}} $ and new equations using fitting parameters. To ensure the scalability of the model, the scaling rules are modified. The proposed model has been validated by comparing the measured and modeled DC $I$ – $V$ characteristics and multibias scattering parameters ( $S$ -parameters) up to 40 GHz for GaN HEMTs with different gate widths including 2 $\times$ 25 $\mu$ m, 2 $\times$ 50 $\mu$ m, 2 $\times$ 75 $\mu$ m, and 2 $\times$ 100 $\mu$ m gate width (number of gate fingers $\times$ unit gate width).

A parameter-extraction approach for determination of the small-signal equivalent circuit model for InP/InGaAs double heterojunction bipolar transistors is presented in this paper. This method combines the advantages of conventional T - and π -type equivalent-circuit topologies. All the equivalent circuit elements are only extracted analytically from S -parameter data without any numerical optimization. The agreements between the measured and the model-calculated data are excellent in the frequency range of 0.1–110 GHz.