In this paper, the relationship between 3db bandwidth and pulse-width, and the relationship between pulse-width and ratio of energy in the microwave spectrum to whole pulse energy, are presented. It is clear to reveal the picosecond EMPs' bandwidth increase exponentially as pulse-width decreasing under 100ps. The picosecond pulses have great potential interference on the traditional microwave devices. The guidance for the design of pulse suppression filter is drawn up and a special high-pass passive device is introduced into the traditional microwave filter to control the parasitic pass-bands for avoiding the interference. The new filter is easy to implement and experimentally validated to effectively attenuate undesired signal amplitudes by −20dB in every parasitic pass-band.