摘要
空间监视雷达系统中,目标的检测与参数估计是首先需要解决的问题。以"电子篱笆"型空间监视雷达为例,研究了分数阶傅里叶变换(FRFT)在其信号处理中的应用。在对空间目标穿越雷达视场时的速度及其变化率进行分析的基础上,建立了空间目标回波信号模型。然后推导出FFT方法的最大信号积累时长的解析表达式,对比分析了基于FFT和FRFT的目标检测性能。最后,对FRFT的参数估计精度进行了推导。研究表明,利用FRFT可以有效地积累目标回波信号的能量,提升加速运动目标的检测性能,对信号参数估计的精度接近于其CRLB。
This paper discusses the use of FRFT(Fractional Fourier Transform) for solving the problem of target detection and parameter estimation in the radar system for space surveillance. First, the velocities and accelerations of space objects crossing radar field of view are analyzed. The model of radar echo signal is established based on the analysis. Then, the target detection performance using FFT(Fast Fourier Transform) and FRFT are analyzed with the maximum integration time of FFT derived before. The accuracy of parameter estimation using FRFT is derived at last. The results indicate that FRFT enhances the detection performance and the precision of parameter estimation using FRFT is close to CRLB(Cramer-Rao Lower Bound).
出处
《雷达科学与技术》
2010年第1期37-43,48,共8页
Radar Science and Technology
关键词
分数阶傅里叶变换
空间监视
目标检测
参数估计
电子篱笆
fractional Fourier transform(FRFT)
space surveillance
target detection parameter estimation fence