Abstract: The poles of target scattering pulses in the frequency domain are particularly stable features in the resonant region. Poles characteristics can reduce the impact of many interference factors during radar feature extraction. On the other hand, ultra-wideband radar is known for its adaptability to complex multipath environment and robust performance in electronic warfare scenarios. This paper simulates the xpole extraction process with impulse radar based on matrix pencil method (MPM) in resonant region. The temporal responses of a specific target by incident pulses with different distributions in time domain are obtained by Fourier transform and radar cross section (RCS) spectrum of the target in frequency domain. As examples, the pole extraction results of slender rod and traditional aircraft show impacts of different incident pulses.