This letter proposes an improved dc-single tone approximation model to calculate the RF-dc conversion efficiency, voltage sensitivity, and input impedance of rectification circuits comprising $n$ diodes. The proposed model is based on the energy balance in the rectification circuit and is validated for general cases when the power losses of higher tones are lower than the dc losses. This condition is observed for frequencies at which the capacitor shunts the nonlinear resistor. A comparison of the results obtained using the derived equations and those from the simulation data obtained using a harmonic balance solver confirms the validity and accuracy of this approach for a wide range of output dc voltages and currents.

中文翻译：

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使用 DC-单音逼近的高频二极管的 RF-DC 转换效率模型

这封信提出了一种改进的直流-单音逼近模型，用于计算包含 $n$ 个二极管的整流电路的 RF-DC 转换效率、电压灵敏度和输入阻抗。所提出的模型基于整流电路中的能量平衡，并在较高音调的功率损耗低于直流损耗的一般情况下得到验证。对于电容器与非线性电阻器分流的频率，会观察到这种情况。将使用导出方程获得的结果与使用谐波平衡求解器获得的仿真数据进行比较，证实了这种方法对于各种输出直流电压和电流的有效性和准确性。