中文摘要：

基于箔条螺旋下降的运动模型，研究了箔条的转动和平动对箔条云回波信号造成的影响，用统计方法研究了箔条云的全极化频谱特性．首先介绍了箔条螺旋下降的运动模型，给出了转动偶极子的极化散射矩阵，在此基础上分析了箔条云散射矩阵元的自相关函数和互相关函数，给出了散射矩阵元的功率谱和交叉功率谱的表达式，然后给出了均匀取向和水平取向箔条云回波频谱的数值结果．

英文摘要：

Based on the spiral descending model of chaff, the effect of both rotation and translational motion of chaff on radar echo of chaff clouds was studied and the full-polarimetric spectral characteristics of radar echoes from chaff clouds were investigated by using statistical method. Firstly, spiral descending model of chaff was described, and the Sinclair matrix of a dipole with rotation was given. Based on the above analysis, auto correlation and cross-correlation functions of the Sinclair Matrix elements were investigated and further power spectrum and cross-power spectrum were derived. At last, some numerical results of radar echo spectra for randomly oriented and horizontally oriented chaff clouds were presented.