Abstract: A novel, compact, and low-cost ultra-short monocycle pulse generating method is presented. It is mainly consist of three parts: the pulse generating circuit composed of step recovery diode and microwave transistor, the pulse shaping circuit with Schottky diode and terminated shunt stub, and the RC differential circuit. The principle and design of the whole circuit was analyzed, and the circuit was simulated by using ADS software. The measured results show that the output waveform has 7.6 V peak-to-peak amplitude and 500 ps pulse duration with very low ringing level. Good agreement between the measured and simulation results is achieved. The monocycle pulse generator is very suitable for through-wall detecting radar transmitter.