摘要
基于大气分层时域信号生成模型(feuilletémodel)进行非平稳信号的仿真。引入时-频域联合分析方法反演风速,对非平稳风速模型下的仿真回波信号进行算法处理研究。基于实际系统参数,分别在线性剪切风速和美国宇航局(NASA)阵风模型下仿真回波信号。对仿真信号作Wigner-Ville变换,通过分析信号时频变换后的能量峰值在时频面内的分布来反演风速。采用多组脉冲累加平均的方式来减少因散斑噪声、交叉项等因素造成的反演风速的波动。结果表明,利用时-频域联合分析方法可以快速反演出风速信息,无需对探测范围进行距离门的划分;对多组信号的时频变换结果做累加平均处理后,反演风速的波动减小,与输入风速的一致性得到了明显的改善。
An atmospheric slices time domain signal generation algorithm model （feuilleté model） is proposed to simulate the signal under non-stationary atmospheric conditions. The wind inversion by means of timefrequency analysis is introduced, and the algorithm processing of signals simulated under non-stationary wind model is studied. Based on the actual system parameters, the echo signals are simulated under conditions of linear wind shear and national aeronautic and space administration （NASA） typical wind shear model, respectively. Wind inversion by analyzing the distribution of peak energy in the time-frequency domain after the application of Wigner-Ville transformation on the simulated signal is got. And in this process, the fluctuation of wind inversion, which results from speckle noise, cross terms and other factors, can be reduced by accumulating multiple time-frequency transforms of pulses. The results show that, wind inversion is obtained quickly and directly by utilizing time-frequency analysis methods and without division of range gate in detection zone. The fluctuation of wind inversion decreases after the processing of accumulation and average, and the similarity between wind inversion and input wind speed is improved significantly.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2015年第1期323-331,共9页
Chinese Journal of Lasers
基金
国家自然科学基金(61178072)
关键词
遥感
相干多普勒测风激光雷达
风速反演
时频分析
时域信号仿真
remote sensing
coherent Doppler wind lidar
wind inversion
time-frequency analysis
timedomain signal simulation
