This paper investigates the linearity of active devices and amplifiers that have modulated input signals. We describe an implementation of a mathematical technique for calculating spectral regrowth due to nonlinear amplification for modulated signals typically used in wireless communication systems. This technique requires only single-tone gain and phase data as a function of input power and can be applied to any modulated signal so long as the device or amplifier characteristics do not change significantly over the band width of the input signal and the modulation frequencies are much less than the carrier frequency. Verification of the mathematical technique is presented using examples of measured and calculated spectra for /spl pi//4-DQPSK PHS (Personal Handy Phone) and CDMA Offset-QPSK PCS (Personal Communication System) modulation schemes. Finally, this calculation technique is used to determine fundamental tradeoffs between device performance (linearity, output power, gain, and power added efficiency) and device bias conditions and load impedance.
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机译:本文研究了具有调制输入信号的有源器件和放大器的线性。我们描述了一种用于计算由于通常用于无线通信系统中的调制信号的非线性放大而计算光谱再生的数学技术的实现。该技术只需要单调增益和相位数据作为输入功率的函数,并且可以应用于任何调制信号,只要设备或放大器特性在输入信号的带宽上没有显着变化,并且调制频率都是如此远低于载波频率。使用用于/ SPL PI // 4-DQPSK PHS(个人方便电话)和CDMA偏移-QPSK PC(个人通信系统)调制方案的测量和计算的光谱的示例给出了数学技术的验证。最后,该计算技术用于确定器件性能(线性,输出功率,增益和功率增加效率)和设备偏置条件和负载阻抗之间的基本折衷。
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