南京大学学报（自然科学版）Issue(1)：30-34,5.DOI:10.13232/j.cnki.jnju.2014.01.005
基于Keystone变换的高速运动目标检测方法研究
Research on high-velocity targets detection based on Keystone transform
摘要
Abstract
The target echo migration usually exceeds a range resolution cell,when the target is moving with a high ve-locity.This causes Doppler frequency spectrum aliasing,and makes it troublesome to accumulate the pulses. Theorily,when the high-velocity target’s signal is at low signal to noise ratio(SNR),accumulating for longer time could develop the detection ability.However,during longer term accumulation,the waves of pulses may exceed several range resolution cells.This makes it much more difficult to pulses accumulation.Estimating speed before detection could develop detection ability in theory.But in fact,it’s very difficult to measure the speed.Even realized,it needs much longer time to archive.This is very difficult to come true in practice.In this paper,theoretical derivation will be carried on particularly.It tells why there would be range migration and Doppler ambiguity,and how to compensate them.Based on the theoretical derivation,a modified method which is based on Keystone transform is put forward.The method is to calculate the differences of all the points of pulses’peaks,which is gotten at different ambiguity factor,and to note the Doppler ambiguity factor when the difference is minimum.This Doppler ambiguity factor can be used to compensate Doppler ambiguity as is shown below.Keystone transform can be realized by the method of SINC interpolation and the method of calculating Doppler ambiguity factor.This method is not restricted by the accumulation time,and doesn’t need to estimate the speed before detection.What’s more,this method could compensate the range migration and Doppler ambiguity without acknowledging the target’s speed.The result shows that,compared with other methods,this method could compensate the range migration and Doppler ambiguity without acknowledging the targets’speeds.It is not restricted by the detection time.It also develops the SNR of the pulses of high-velocity targets,and Radars’detection ability in wideband radar.This method is of great value in practice,especially in millimeter wave radar.关键词
越距离单元走动/Keystone变换/多普勒模糊/相参积累Key words
range resolution cell/keystone transform/doppler ambiguity/pulses accumulate引用本文复制引用
高玉祥,张兴敢,柏业超..基于Keystone变换的高速运动目标检测方法研究[J].南京大学学报（自然科学版）,2014,(1):30-34,5.基金项目
江苏省产学研联合创新资金---前瞻性联合研究项目(BY2012187) （BY2012187）
