摘要
利用幂级数和高阶累计量的统计方法,推导出基于IS-95模型前向信道的CDMA(码分多址)信号通过弱非线性RF功率放大器产生的频谱增生的严谨表达式,通过仿真验证其正确性.并由此获得了经该放大器特征模型变换的输出信号自相关函数的解析表达式.用三阶截断点IP3表示了包含带内和带外电抗的记忆效应三阶非线性.频谱增生的分析结果可直接用于工程计算,这对于确定射频功率放大器最佳的工作条件是十分有价值的.根据推导出的算法进行仿真,并与ADS软件进行仿真结果进行比较,以说明其正确性.
Closed-form expressions for the spectral regrowth of code division multiple access （CDMA） signal passed through a nonlinear amplifier by a digitally modulated carrier are derived using the power series and statistical methods of high order cumulant. The technique yields an analytical expression for the autocorrelation function of the output signal as a function of the statistics of the input signal transformed by a behavioral model of the amplifier. The third-order nonlinearity is expressed in terms of IP3 to include the memory effects of the circuit in-band and out-of-band reactance.The analysis is based on a time-domain model of the signal and the model is used to derive the power spectrum density and other statistical properties of the CDMA signal. Such analytical results are useful in finding optimal operating conditions of the power Amplifier.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2005年第10期1872-1875,共4页
Acta Electronica Sinica
基金
国家自然科学基金(No.60372051)
武器装备预研基金(No.51487011504HT0101)
关键词
频谱增生
码分多址
功率谱密度
自相关函数
高阶累计量
spectral regrowth
CDMA
power spectrum density
auto-relation function
high order cumulant
