摘要
宽带分布式全相参雷达具有高距离分辨力和高角度分辨力,可在实现对目标探测的同时获得更为精细的信息。其中,准确的相参参数是实现宽带全相参的关键。在远距离探测场景下,目标回波SNR较低,导致单部雷达无法探测到目标。如何在此情况下准确地估计相参参数,完成多部雷达相参合成,是分布式全相参雷达实现远距离探测的核心问题。本文首先建立了针对高速运动复杂目标的宽带Chirp去斜回波模型,并建立了相参参数的数学模型。然后,提出了基于MUSIC法的宽带分布式全相参雷达相参参数估计方法,通过估计观测目标的散射点个数、极点以及复幅度,重建宽带回波信号,并基于该无噪声重建信号估计相参参数。最后,利用仿真分析验证了本文提出方法在低SNR下的有效性。
Wideband distributed coherent aperture radar can achieve more subtle information when detecting targets,due to its high range resolution and high angle resolution.And accurate coherent parameters are keys to wideband full coher-ence.When detecting long-range target,single radar always fail because of its relatively low SNR.Therefore,accurately estimating the coherent parameters in order to achieve coherent synthesize under low SNR is core in long-range detection of distributed coherent aperture radar.In this paper,the wideband dechirped echo model of high velocity complex target is built firstly.The mathematical expression of coherent parameters is presented.Then a novel coherent parameters estimation method based on MUSIC in wideband distributed coherent aperture radar is proposed.The number of the target’s scattering centers,the corresponding poles and complex amplitudes of the scattering centers can be estimated,resulting in the noise-less rebuild signal.Based on this clean signal,coherent parameters are estimated.Finally,simulations are carried out to illustrate the performance of proposed methods under low SNR.
出处
《信号处理》
CSCD
北大核心
2015年第2期208-214,共7页
Journal of Signal Processing
基金
国家自然基金(61301189)
高等学校学科创新引智计划资助(B14010)
关键词
宽带分布式全相参雷达
去斜回波模型
相参参数估计
低SNR
MUSIC
wideband distributed coherent aperture radar
dechirped echo model
low SNR
MUSIC
coherent parame-ters estimation
