基于分数阶模糊函数线调频率延时对消的运动弱目标检测  

Weak Target Detection Based on LFM-delay Fractional Ambiguity in Sea Clutter

作　　者：郭海燕[1] 关键[1] 

机构地区：[1]海军航空工程学院,烟台264001

出　　处：《信号处理》2011年第5期760-764,共5页Journal of Signal Processing

基　　金：国家自然科学基金资助(60672140;60802088);"泰山学者"建设工程专项经费资助;航空科学基金(批准号20095184004)

摘　　要：针对回波信号相位中存在的三次项问题,文中介绍了分数阶模糊函数的定义及部分性质,在此基础上研究了含有三次项的运动目标回波信号的分数阶模糊函数的线性调频延时特性,根据此特性文中提出了一种海杂波背景下的基于分数阶模糊函数线调频延时对消的运动弱目标检测方法。该方法通过将原信号的分数阶模糊函数模函数与线性调频延时后信号的分数阶模糊函数模函数对消,能在基本不减弱信号分数阶模糊函数模值的情况下有效地对消部分杂波,达到提高信杂比,提高检测性能的目的。最后,通过对IPIX实测数据验证表明,所提方法在增加目标与杂波分数阶模糊函数域峰值差以及提高信杂比等方面都明显优于仅对回波作分数阶模糊函数。文中采用双参数恒虚警检测方法设置适当的门限,该检测方法能够达到更好的检测效果。In the paper,the definition and partial character of fractional ambiguity is introduced.Based on the introduction the LFM-delay characteristic of fractional ambiguity is investigated for the echo that has high polynomial.Based on the characteristic a new method based on the difference of LFM-delay fractional ambiguity model for moving weak target detection in sea clutter is proposed.The method can difference partial clutter effectively and can not difference the fractional ambiguity model of signal at the same time when difference the fractional ambiguity model of the signal and the fractional ambiguity model of the LFM-delay signal.The signal to clutter ratio and the detection performance can be increased by the method in the paper.At last the method is Experiment using the IPIX radar data shows that the method of the paper has remarkably advantage in increasing the difference of the peak value of the signal in the domain of fractional ambiguity and the peak value of the clutter in the same domain,and increasing the signal to clutter ratio compared with fractional ambiguity.Biparametric constant false alarm rate is introduced in the paper.Setting right CFAR detection threshold,the target can be better detected by the method of the paper.

关 键 词：分数阶FOURIER变换 线性调频延时 分数阶模糊函数 

分 类 号：TN957.5[电子电信—信号与信息处理]