为了提高通信系统的信息传输速率，人们提出了UWB通信系统，即Ultra-Wideband 通信系统。在UWB系统中，信号的带宽一般都在GHz的量级，这么宽的带宽造成了UWB系统和现有的通信系统频谱的重叠。为了降低对现有通信系统的影响，UWB信号的设计需要满足一定的频谱模板。如果一个信号的频谱基本满足频谱模板的规定（即在绝大部分频段内功率小于规定区间的上限），我们可以认定其为一个UWB信号。-In order to improve communication systems, information transmission rate of UWB communications systems have been proposed, namely, Ultra-Wideband communication systems. In the UWB system, the signal bandwidth will generally be in the order of GHz, caused such a wide bandwidth of UWB system and the existing communications system spectrum overlap. In order to reduce the impact of the existing communication systems, UWB signal design needs to meet certain spectral mask. If a signal spectrum can basically meet the spectral mask (that is, in most of the provisions of band power is less than the maximum range), we can assume it as a UWB signal.