A method to predict intermodulation (IM) products of two tone test based on Amplitude to amplitude (AM-AM) and amplitude to phase (AM-PM) diagrams of power amplifier is proposed in this paper. An RF power amplifier is...A method to predict intermodulation (IM) products of two tone test based on Amplitude to amplitude (AM-AM) and amplitude to phase (AM-PM) diagrams of power amplifier is proposed in this paper. An RF power amplifier is mathe-matically modeled by a power series in order of 13. Coefficients of the transfer function are obtained by odd-order polynomial fitting of the transfer function of the power amplifier that is modeled by power series, with AM-AM and AM-PM diagrams. Because of considering AM-PM distortion, coefficients have become complex. By using this transfer function, analytical expressions of IM products are derived. Frequency effect of IM products are modeled in suggested method to estimate the effects of changing in input frequency on output. With the mean of this factor the model is able to predict IM products of wideband frequency input. Simulated results agree well with the predicted method in comparisons.展开更多
针对功率放大器的失真特性,包括幅度失真和相位失真,利用反并联的肖特基二极管完成了一种新型预失真线性化器的设计和制作。仿真和实验测试结果表明,所设计制作的微波电路能在偏置电压的控制下调节AM-AM(amplitude to ampli-tude conver...针对功率放大器的失真特性,包括幅度失真和相位失真,利用反并联的肖特基二极管完成了一种新型预失真线性化器的设计和制作。仿真和实验测试结果表明,所设计制作的微波电路能在偏置电压的控制下调节AM-AM(amplitude to ampli-tude conversion)和AM-PM(amplitude to phase conversion)转换特性,该特性能补偿行波管失真特性;并且具有体积小、结构相对简单、调节容易、性能稳定、适合于工程实现等优点。展开更多
AM 1 and PM 3 SCF MO calculation have been performed to obtain molecular geometries of 7 1 isopropyl silacyclohexane based liquid crystal compounds biphenyl ethane series by energy gradient completed optimization.For ...AM 1 and PM 3 SCF MO calculation have been performed to obtain molecular geometries of 7 1 isopropyl silacyclohexane based liquid crystal compounds biphenyl ethane series by energy gradient completed optimization.For all optimized configurations,there is no imaginary frequency in vibrational analysis.The stable configuration,electronic structure,and some molecular properties of title compounds(heat of formation,dipole moment and energy level of frontal molecule orbital,etc) are frist reported.The calculated results are fully discussed with rspect to the organic structure theory.展开更多
文摘A method to predict intermodulation (IM) products of two tone test based on Amplitude to amplitude (AM-AM) and amplitude to phase (AM-PM) diagrams of power amplifier is proposed in this paper. An RF power amplifier is mathe-matically modeled by a power series in order of 13. Coefficients of the transfer function are obtained by odd-order polynomial fitting of the transfer function of the power amplifier that is modeled by power series, with AM-AM and AM-PM diagrams. Because of considering AM-PM distortion, coefficients have become complex. By using this transfer function, analytical expressions of IM products are derived. Frequency effect of IM products are modeled in suggested method to estimate the effects of changing in input frequency on output. With the mean of this factor the model is able to predict IM products of wideband frequency input. Simulated results agree well with the predicted method in comparisons.
文摘针对功率放大器的失真特性,包括幅度失真和相位失真,利用反并联的肖特基二极管完成了一种新型预失真线性化器的设计和制作。仿真和实验测试结果表明,所设计制作的微波电路能在偏置电压的控制下调节AM-AM(amplitude to ampli-tude conversion)和AM-PM(amplitude to phase conversion)转换特性,该特性能补偿行波管失真特性;并且具有体积小、结构相对简单、调节容易、性能稳定、适合于工程实现等优点。
文摘AM 1 and PM 3 SCF MO calculation have been performed to obtain molecular geometries of 7 1 isopropyl silacyclohexane based liquid crystal compounds biphenyl ethane series by energy gradient completed optimization.For all optimized configurations,there is no imaginary frequency in vibrational analysis.The stable configuration,electronic structure,and some molecular properties of title compounds(heat of formation,dipole moment and energy level of frontal molecule orbital,etc) are frist reported.The calculated results are fully discussed with rspect to the organic structure theory.
