Abstract:

This paper mainly introduces the operating principle of human life detection system using UWB radar,and compares several methods on ultra-short pulses generating.Taking into consideration the avalanche transistor principle,this paper comes up with using the avalanche characteristics of the avalanche transistor to achieve ultra-wideband radar ultra-short pulse generating principle.Through researching and analyzing the typical pulse generating circuit,this paper works out the pulse signal generator circuit on detection system of human life.Experimental simulation results show that:the circuit can generate a pico-second bipolar pulse and peak-up of the narrow pulse can reach up to 2 V.It can meet the micro power impulse radar system which can be applied in the field of life signal detection requirements.

Key words: ultra wideband;pulse generator;avalanche transistor;ultra-short pulse