空间插值在功率谱密度计算中的应用  

Application of spatial interpolation to calculation of power spectrum density

作　　者：徐建程[1,2] 许乔[2] 柴立群[2] 

机构地区：[1]浙江师范大学信息光学研究所,浙江金华321004 [2]成都精密光学工程研究中心,成都610041

出　　处：《强激光与粒子束》2010年第7期1520-1524,共5页High Power Laser and Particle Beams

基　　金：浙江师范大学青年基金项目(KYJ06Y09108);浙江师范大学博士科研启动基金项目(ZC304010012)

摘　　要：为了提高光学元件波前中频PSD计算的精度和有效频谱宽度,提出了填补波前无效数据的双线性插值法和抑制欠采样噪声的六采样点插值法。模拟计算和实验结果表明:双线性插值法有效地保证了填充数据与真实数据的一致性,抑制了零填充方法引入的虚假中高频信息,使得填补后的PSD与原始PSD较好地吻合;六采样点插值法有效地分离了信号和欠采样噪声,使得有效PSD频谱上限从1/2 Nyquist频率提高到Nyquist频率。To improve the precision and effective spectrum width scale, double linear interpolation and six-sample-wide interpolation are of wavefront power spectrum density（PSD） at mid-spatial proposed to patch invalid points and reduce aliasing noise, respectively. Double linear interpolation reduces discrete discontinuities and retains spectral structure of the valid areas, without adding visible middle and high spatial frequency errors existing in zero-filled method. Six-sample-wide interpolation effectively sep- arates the signal from the aliasing noise and thus increases the effective spectrum upper limit of PSD from half of Nyquist frequen- cy to Nyquist frequency. The validity of double linear interpolation and six-sample-wide interpolation is verified by computer simu- lation and experiment.

关 键 词：功率谱密度 六采样点插值 双线性插值 欠采样噪声 

分 类 号：O436.1[机械工程—光学工程]