摘要: |
鸟类扑动的翅膀产生的微多普勒包含了目标的尺寸与微动特征信息,可用于鸟类目标参数估计,对探鸟雷达目标识别具有重要意义。首先建立鸟类目标雷达回波模型,推导了鸟翅膀散射点的微多普勒数学表达式,并通过计算回波的自相关函数估计目标扑翼频率;然后对微多普勒表达式进行泰勒级数展开,利用展开系数与扑翼幅度之间的关系得到扑翼幅度的估计值;最后根据半翼展与微多普勒谱宽之间的关系得到半翼展的估计值。仿真实验证明了所提方法的有效性和抗噪性:对扑翼幅度大于30??、半翼展大于0.3 m的目标,在信噪比高于0 dB的噪声环境下估计精度高。 |
关键词: 雷达目标识别 探鸟雷达 微多普勒 参数估计 |
DOI: |
|
基金项目: |
|
Micro-Doppler analysis and parameter estimation of bird target |
CHEN Hongkun,CHA Hao,LIU Feng |
(School of Electronics Engineering,Naval University of Engineering,Wuhan 430033,China) |
Abstract: |
Micro-Doppler signatures produced by bird′s beating wings can reflect target′s geometry and precession characteristics,which can be used to estimate bird parameters,and is of great significance for target recognition of avian radars.Firstly,a radar echo model of bird is established,and the mathematical expressions of micro-Doppler induced by bird's wing scatter points are derived,and the bird beating frequency is estimated by calculating the autocorrelation function of the radar echo.Secondly,the Taylor series expansion is performed on the micro-Doppler frequency,and the relationship between the flap amplitude and the expansion coefficients is used to estimate the flap amplitude.Finally,an estimate of the semispan is obtained based on the relationship between the semispan and the micro-Doppler spectral width.The simulation results validate the effectiveness and noise resistance performance of the proposed method:for targets with a flap amplitude greater than 30° and a semispan greater than 0.3 m,the estimation accuracy is high when signal-to-noise ratio is higher than 0 dB. |
Key words: radar target recognition avian radar micro-Doppler parameter estimation |