基极注入HPM导致的双极型晶体管失效分析简

In order to determine the influence of HPM on BJT, the physical process and model are proposed based on the experimental phenomena of BJT injecting HPM from the base. Simulation results by using the model and process proposed in the paper show that the main mechanism of failure and degradation of BJT caused by HPM is that the induced voltage pulse generated by HPM leads to the burn-up and the formation of the fuse element and defect in the base. The burnt area and the number of defects which vary with the power and time of HPM on the devices cause the device failure and the change of DC characteristics.The simulation result is in good agreement with the phenomena of the BJT HPM effect experiment, which indicates that the analysis in this paper is correct.     

基于时频图的飞机目标特征提取算法

研究了两种基于时频分析的飞机目标特征提取算法。首先,介绍利用短时傅里叶变换获得目标二维时频图信息,然后,分析飞机目标回波时频图的图像熵特征和平均时频谱特征,给出了这两种特征的提取算法,仿真得到利用这些特征对三类飞机的分类识别结果,分析了其目标分类识别性能以及适用情况。在研究时频图平均时频谱特征提取算法时,发现单独使用此特征在飞机目标分类识别中存在的问题,加入基于平均时频谱的方差特征,综合两种特征实现了对三类飞机目标的的分类识别。仿真结果表明,这两种特征的目标识别正确率都能达到94％以上。