基于局部离群因子的HRRP开集识别特征选择方法

Feature Selection Method for Open Set HRRP Recognition Based on Local Outlier Factor

  • 摘要: 特征选择是雷达目标识别流程中一个较为关键的环节,通过对原始特征集进行筛选,挑选出其中的优质特征构成新的特征子集,可以有效增加识别准确率,提升识别效率。为了提升开放环境下高分辨距离像(High Range Resolution Profile,HRRP)的识别性能,针对现有特征选择方法基于闭集假设,无法有效应对实际应用中存在库外目标导致的开集识别(Open Set Recognition,OSR)性能下降问题,本文提出了一种基于局部离群因子(Local Outlier Factor,LOF)的HRRP开集识别特征选择方法。首先,从原始HRRP中提取15维特征向量作为原始特征集;其次,该方法引入聚合性概念,并使用LOF作为其度量,通过评估特征子集的聚合性来保证其在OSR时具有最小的开放空间风险。同时,采用重心法评估特征子集的可分性,并使用前向搜索算法优化特征选择过程,确保所选特征子集为维数约束下的最优解。实验结果表明:利用所提方法选择的特征子集在开集环境下识别性能优于现有特征提取方法,提升了开集环境下高分辨距离像的识别性能。

     

    Abstract: ‍ ‍Feature selection is a crucial part of the radar target recognition process. Recognition accuracy and efficiency can be enhanced by selecting high-quality features from the original set of features to form a new subset. In practical applications, the existing feature selection methods, which are based on the closed-set assumption, may cause performance degradation in open set recognition (OSR) caused by the presence of out-of-database targets. To enhance the recognition performance of high-resolution range profiles (HRRPs) in open environments, a feature selection method for HRRP OSR based on the local outlier factor (LOF) is proposed in this study. First, 15-dimensional feature vectors are extracted from the original HRRPs as the initial feature set. Second, the concept of feature aggregation is introduced and the LOF is used for its measurement, ensuring minimal open space risk during OSR by evaluating the aggregation of feature subsets. Additionally, the separability of feature subsets is assessed using the centroid method to guarantee good inter-class discrimination. Finally, the feature selection process is optimized using a forward search algorithm to ensure that the selected feature subset is the optimal solution under dimensional constraints. Experimental results demonstrate that the proposed method outperforms mainstream feature extraction methods regarding features selected in open set environments, and the recognition performance of HRRPs in OSR scenarios is improved.

     

/

返回文章
返回