The first key problem of the neural network mode recognition system emphatically have studied, namely mode pretreatment and characteristic drawn, then it shows the basic K-L varies to realizy PCA and how to realize the method step of PCA especially;

• 着重研究了神经网络模式识别系统的第一个关键问题，即模式的预处理和特征提取，重点分析了PCA的理论实现基础K-L变换和实现PCA的方法步骤；