摘要
辐射源LFM信号的参数估计常采用基于分数阶傅里叶变换的方法,分数域最优阶次的搜索容易受到搜索间隔的影响,导致计算精度和计算量之间的矛盾。基于改进的二阶振荡粒子群算法,提出一种与分数域展宽法相结合的参数估计方法。该方法利用不同辐射源脉冲之间初始相位不同的原理,在时域上进行辐射源信号与干扰信号的相参性识别;通过改进的二阶振荡粒子群算法搜索最小分数域展宽值,计算最优阶次,从而得到信号参数估计值,解决了最优阶次的精确与否受限于搜索间隔的问题,并与多种其他算法进行了对比仿真。结果表明,改进方法能在混合信号中准确识别出目标辐射源信号,且能在低信噪比条件下快速估计出信号参数,提升了参数估计的性能。
Usually,the method based on the fractional Fourier transform is adopted in the parameter estimation of the LFM(linear frequency modulation)signal of the radiation source.The search for the optimal order in the fractional domain is susceptible to the search interval,which leads to the contradiction between the calculation accuracy and the amount of calculation.In view of this,a parameter estimation method combined with the fractional domain widening method is proposed on the basis of the improved second⁃order oscillating particle swarm optimization(PSO)algorithm.In this method,the principle that the initial phases of different radiation source pulses are different is used to identify the coherence of the radiation source signal and the interference signal in the time domain.By the improved second⁃order oscillation PSO algorithm,the minimum fractional domain widening value is searched for and the optimal order is calculated,so as to obtain the estimated value of the signal parameter,which avoids the fact that the accuracy of the optimal order is limited to the search interval.The proposed method is contrasted with a variety of other algorithms by simulation.The results show that the improved method can accurately identify the target radiation source signal from the mixed signals,and can quickly estimate the signal parameters under the condition of low signal⁃to⁃noise ratio(SNR),which improves the performance of parameter estimation.
作者
张艳睛
龙伟军
潘明海
ZHANG Yanjing;LONG Weijun;PAN Minghai(Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China;Nanjing Institute of Electronic Technology,Nanjing 210013,China)
出处
《现代电子技术》
2022年第15期63-68,共6页
Modern Electronics Technique
基金
国家自然科学基金项目(62071440)。
关键词
参数估计
目标辐射源
LFM信号
最优阶次计算
分数域展宽
信号识别
二阶振荡粒子群算法
parameter estimation
target radiation source
LFM signal
optimal order calculation
fractional domain widening
signal recognition
second⁃order oscillation PSO algorithm
