基于Ransac算法的捷变频联合正交频分复用雷达高速多目标参数估计

在现代雷达电子战场中，目标检测与其参数估计有着非常重要的意义。因此，该文提出了一种基于随机抽样一致算法(Ransac)的捷变频联合正交频分复用(FA-OFDM)雷达高速多目标参数估计的方法。首先，在传统捷变频雷达的每个脉冲内同时发射多个频率随机跳变的窄带OFDM子载波。将单个脉冲内所有子载波的回波信号进行脉冲压缩后，采用迭代自适应谱估计(IAA)算法合成目标的高分辨距离。然后，分别对各个脉冲的回波进行脉冲压缩和迭代自适应谱估计，得到不同脉冲时刻的高分辨距离，构成观测数据集。再根据Ransac算法估计信号参数模型的步骤，拟合多条时间-距离直线，进而对高速运动的多个目标同时进行参数估计。最后，分别分析了信噪比(SNR)对检测概率以及目标自身速度对其相对估计误差的影响。仿真实验验证了所提算法的有效性。

High Speed Multi-target Parameter Estimation for FA-OFDM Radar Based on Ransac Algorithm

In modern radar electronic battlefield, target detection and parameter estimation have great significance. Therefore, a high-speed multi-target parameter estimation method for Frequency Agile-Orthogonal Frequency Division Multiplexing (FA-OFDM) radar based on Random sampling consensus (Ransac) algorithm is proposed in this paper. Firstly, multiple narrowband OFDM subcarriers with random frequency hopping are simultaneously transmitted in each pulse of conventional frequency agile radar. The echo signals of all subcarriers in a single pulse are compressed, and then the high-resolution range of the target is synthesized by Iterative Adaptive Approach (IAA) algorithm. Furthermore, the echoes of each pulse are compressed and iterative adaptive spectrum estimated, and the high-resolution distance of different pulse time is obtained to form the observation data set. Then, according to the steps of the Ransac algorithm to estimate the signal parameter model, multiple time-distance lines are fitted, and then parameters of multiple high-speed moving targets are estimated at the same time. Finally, the influence of the Signal-to-Noise Ratio (SNR) on detection probability and the target velocity on relative error of estimation are analyzed, respectively. Simulations are provided to verify the effectiveness of the proposal.