Summary: Due to the ultra low power spectral desity of the ultra-wide band (UWB), narrow band interference (NBI) with high-level emission power will degrade the accuracy of UWB ranging system. We propose a novel waveform to suppress the accuracy degradation by NBI with a given frequency. In addition, we compare the ranging error ratio (RER) of the proposed scheme with the traditional one with Gaussian monocycle in this letter.