基于LTE信号的小目标回波相参积累:目标散射建模与影响分析

长时间的信号积累是提高微弱慢速小目标探测的一种有效方法，但积累时间长，目标回波会发生越距离单元和多普勒单元走动，相参积累困难。本文对基于LTE信号的小目标探测问题开展研究，引入目标散射空变性，建立了基于LTE通信体制的系统回波模型；在此基础上，分析了目标回波距离走动和多普勒走动特性，提出了基于keystone变换和分数阶傅里叶变换（FRFT）的回波相参积累技术；基于典型目标散射模型，分析了目标散射特性对积累效果的影响，并在典型系统条件下开展了仿真实验，验证了所提算法和分析的有效性。 

Coherent Integration of Small Target Echoes Based on LTE Signals: Target Scattering Modeling and Impact Analysis

Long-time signal integration is an effective method to improve the detection of weak and slow small targets. However, during long time integration, the echoes of the target may exceed several range resolution cells and have Doppler frequency dispersion which makes the target echoes difficult to coherent integration. In this paper, the small target detection problem based on LTE signals is studied, the target scattering variability is introduced into the signal model and the system echo model based on LTE communication system is established. On this basis, the range migration and Doppler dispersion characteristics are analyzed. An echo coherent integration technique which is based on keystone transform and Fractional Fourier Transform (FRFT) is proposed to correct the range migration and Compensate the Doppler dispersion. And based on the typical target scattering model, the influence of target scattering characteristics on the coherent integration effect is analyzed; The simulation experiments are carried out under typical system conditions to verify the effectiveness of the proposed algorithm and analysis.