基于分数阶Fourier域滤波的单电磁传感器宽带Chirp信号二维DOA估计  

Two-Dimensional DOA Estimation of Broadband Chirp Signals with a Single Electromagnetic Vector Sensor Using Fractional Fourier Filtering

作　　者：顾陈[1] 何劲[1] 朱晓华[1] 刘中[1] 

机构地区：[1]南京理工大学电子工程系,南京210014

出　　处：《宇航学报》2010年第4期1136-1142,共7页Journal of Astronautics

基　　金：中国博士后科学基金(20080431098)

摘　　要：提出一种基于单个电磁矢量传感器的宽带Chirp信号方位-仰角估计算法。对强度相差不大的信号,该算法利用分数阶Fourier变换分别估计不同信号的电磁矢量传感器导向矢量,并根据矢量叉积运算得到方位-仰角估计值。对强度相差较大的信号,该算法利用分数阶Fourier域滤波,采用逐次消去的方法分别估计电磁矢量传感器导向矢量,得到方位-仰角估计值。提出的算法不需要进行迭代搜索和二维DOA的配对,不受近场信号的球面波效应的影响,并且可估计具有相同或不同调频斜率的多个Chirp信号的二维DOA。计算机仿真试验证明了算法的有效性。This paper proposes a new Azimuth-elevation angle estimation algorithm for multiple broadband chirp signals using a single electromagnetic vector sensor.Two distinct signal scenarios are considered.For multiple signals with same power,the proposed algorithm applies the fractional Fourier transform（FrFT） to estimate the steering vectors of electromagnetic vector sensors,and then to obtain azimuth-elevation angle estimates using vector cross product.For multiple signals with different powers,the proposed algorithm uses fractional Fourier domain filtering to estimate and eliminate steering vectors of electromagnetic vector sensors one by one,and then to get azimuth-elevation angle estimates of different signals separately.The proposed algorithm requires no iterative searching and pair matching procedures,avoids the complicating effects of a near-field wave front＇s curvature,works well for multiple chirps having the same or distinct chirp rate.Monte-Carlo simulations are presented to verify the proposed algorithm＇s efficacy.

关 键 词：电磁矢量传感器 DOA估计 宽带信号 分数阶FOURIER变换 

分 类 号：TN951[电子电信—信号与信息处理]