An Analytical Harmonic-Aware Model for Predicting Diode Loss and Output Power in RF Rectifiers

Abstract

This study proposes an analytical modeling approach for predicting diode power loss and the maximum power conversion efficiency (PCE) of RF rectifiers. The aim is to provide practical design guidelines for both RF rectifiers and diode device designs. The proposed model accounts for the interaction between the nonlinear diode junction and higher-order harmonic components under harmonic termination conditions. The model also allows quantitative evaluation of the major diode-related power-loss mechanisms under nonlinear operating conditions. Given the diode SPICE parameters, operating frequency, load resistance, and input power, the proposed approach predicts the maximum dc output power and the corresponding rectification efficiency. In addition, a breakdown-voltage constraint is incorporated to identify the feasible operating region under practical device limitations. The validity of the proposed model is confirmed through comparisons with circuit-level simulations performed using a commercial simulator. The results show close agreement over a wide range of operating conditions.