摘要
多普勒信号具有频率不变、相位和幅度随机取值的特点。为了获得多普勒信号的功率谱,用Welch法对功率谱进行估算,采用Goertzel对功率谱进行细化和能量重心校正。对实测多普勒信号进行仿真,结果表明:当重叠数是窗函数长度1/2时,用Welch法估算得到的方差和偏差能够达到较好的效果;频谱细化可以提高功率谱的分辨率;频谱校正使得多普勒频移更接近真实值。
Doppler signal has characteristics of constant frequency and random values of phase and amplitude.In order to obtain the power spectrum of Doppler signal,the power spectrum is estimated via Welch-method,Doppler spectrum is thinned via Goertzel and corrected with energy centro-baric method.Real-time Doppler signal is simulated.The results demonstrate that variances and deviations of the estimation with Welch-method can gain better effect when the overlap number is half of window function length,frequency spectrum thinned can enhance the resolution of power spectrum,and frequency spectrum correction can make Doppler shift close to the real value.
出处
《安徽工业大学学报（自然科学版）》
CAS
2012年第2期150-153,161,共5页
Journal of Anhui University of Technology（Natural Science）
基金
安徽省高校优秀青年人才基金项目(2010SQRL038)
关键词
激光多普勒
周期图
频谱细化
频谱校正
laser Doppler
periodogram
frequency spectrum refinement
frequency spectrum correction
