频谱共存和兼容是超宽带无线通信系统的一个关键问题。为避免该系统与现有无线通信系统之间的相互干扰，同时尽可能地利用频谱资源，有必要对脉冲波形进行合理设计。本文在脉冲信号的时频分析基础上，设计了一种具有升余弦滚降频谱的超宽带脉冲波形，该脉冲波形时域持续时间短，频域上满足FCC的规定；并构造出具有正交特性的时域脉冲波形，使之适用于高阶调制下的超宽带系统。

Coexistence and compatibility of spectrum are important aspects needed to be considered in impulse radio ultra-wideband (IR-UWB) communications. The proper waveforms of signal can decrease the influence of interference between the IR-UWB and extant systems, and improve the efficiency of spectrum resources. In this paper, based on time-frequency analyses, a novel method to design the waveforms of IR-UWB signals is proposed. The constructed waveforms are with raised cosine roll-off frequency spectrum and less time duration. Furthermore, series of time domain waveforms with orthogonal properties constructed by this method can be adopted at high-level modulated UWB systems.