In order to establish the mathematical integration model of the pyroelectric infrared (PIR) sensor mechanism and the characteristics of human body thermal radiation and understand the relationship on PIR sensor between the human body thermal radiation and induction and the human characteristics

this paper studied the working principle of the PIR sensor and the laws of mobile body induction in the PIR sensing regions. The mapping relationship between human characteristics and mechanism of PIR sensing is deduced

which reveals the intrinsic logical connection between induction data and the human radiation source and PIR sensors characteristics. The experimental data show that the higher the human body radiation temperature is

the greater the radiation energy per unit area and the detected voltage amplitude will be; the faster the velocity is

the smaller the detected voltage amplitude will be; the bigger the human body is

the larger the detected voltage amplitude and the radiation area will be. At the same time

the experimental results also verify the correctness and validity of the proposed mathematical model.