Design a pyroelectric IR（PIR） system applied in outdoor environment

and innovatively propose a method using single PIR node to classify vehicles and personnel.The classification algorithm uses signal amplitude

duration of signal

the maximum value of absolute value of the first order difference as feature vector

and use support vector machine（SVM） for target classification.Classifying accuracy is 93.5 % and 94.5 % when PIR detectors are deployed 10 m and 20 m away from the area of interest

and the compositive classification accuracy is 92 %.The system extends the application range and scenarios of pyroelectric sensor and the proposed classification method has a certain reference meaning for other similar sensor systems.