一种面向信号分类的匹配追踪新方法

A New Matching Pursuit Algorithm for Signal Classification

匹配追踪(MP)的主要策略是通过每次迭代时选择一个局部最优解,从而逐步逼近原始信号。然而传统的MP系列算法进行原子匹配时,各类原子集间存在交集,从而影响了原子的表示能力以及相应的分类效果。基于此,该文提出一种适用于信号监督分类的匹配追踪新算法。其原子挑选的准则为:同类信号采用相同的原子集匹配,获取相同的类内表示结构;异类信号选择不同的原子集匹配,从而增强信号的类间差异。示例分析表明,使原子集间相互独立,能够减少异类信号间的共性因素,强化信号间的区分度,从而有利于提升分类识别效果。通过在标准图像库和实测雷达辐射源信号集上的实验表明,较之传统的MP系列方法,所提算法对噪声和遮挡具有更强的鲁棒性。

The main idea of Matching Pursuit （MP） is to get a local optimal solution by iteration, so as to gradually approach the original signal. To cope with the intersection of different atom sets, which may affect the classification performance of conventional MP methods, a new matching pursuit algorithm is proposed, which is suitable for supervised classification. The criterion for atoms selection consists of two parts. On one hand, by using the same atom set within the class, the intra-class structure of the similar signals is obtained for class-representation;on the other hand, by selecting the atom sets independently for every class, the discrimination ability for different classes could be further strengthened. The analysis on a toy example indicates that this scheme reduces the common factors between different classes and highlights the discrimination between signals, which may boost the performance of signal classification. Finally, the experiments on benchmark image databases and the measured radar emitter signals verify that the proposed algorithm achieves better robustness against noise and occlusion, compared with the convention MP-related methods.