基于循环平稳分析的LFM信号盲处理结果可靠性评估

针对线性调频(LFM,Linear Frequency Modulation)信号盲处理结果的可靠性评估问题,提出了一种基于循环频率特征分析的处理算法.首先对观测信号进行调制方式识别及参数估计,并据此建立参考信号,后将观测信号与参考信号作相关运算.通过检测相关序列在零频率附近是否存在循环频率,实现对LFM信号盲处理结果的可靠性检验.文中对所提出检验算法的错误概率进行了理论推导,并以常用的离散多项式变换(DPT,Discrete Polynomial Transform)法为例进行了实证分析.仿真结果表明,相对于已有时域方法而言,本文算法无需估计信噪比,且在低信噪比条件下具有更好的统计性能.

Reliability Evaluation for Blind Processing Results of LFM Signal Based on Cyclostationarity

A reliability test method based on cyclic frequency features was proposed to evaluate the blind processing results of linear frequency modulation (LFM)signal.The reference signal was constructed depending on the identified mod-ulationtype and the correspondent parameters estimations at first and the correlations between the observed signal and the ref-erence signal were calculated consequently.The reliability for LFM signal processing result was tested by detecting the pres-ence of cyclic frequencies near zero frequency of the correlations.The theoretical error probability of the detection was de-rived and the case study for the discrete polynomial transform (DPT)method was described in the paper.Simulation results show that the proposed algorithm avoids estimating of signal-to-noise ratio and is superior to the time domain based method under lower signal-to-noise ratios.