一种新的直扩超宽带系统快速同步方案

本文提出了一种新的基于能量窗的直扩超宽带系统码片同步方法，通过设计具有重复特性的码来提高能量窗的信噪比，从向可以较为准确地获得码片同步，并将窗口中的信息作为接收端本地信号与接收信号进行匹配接收，这样可以存未知接收信号相位的情况下有效地接收多径能量，提高接收信噪比。在完成码片同步之后再进一步进行PN码的相位同步，这里以线性搜索为例分析得到超宽带信号总的平均同步时间，并与现有的超宽带同步方案进行了比较，新方案将信号捕获分成两部分完成，大大降低了超宽带信号捕获时间。

A new rapid acquisition scheme for DS-UWB system

In this paper, a new chip acquisition scheme, based on energy window, is proposed for DS-UWB system. To improve the signal to noise ratio in the energy window, a preamble with repetition property is employed. The new scheme separates the acquisition procedure into two steps: chip acquisition and PN code synchronization. Once the chip acquisition achieved, the multipath components can be acquired without the knowledge of channel information, by utilizing the samples in energy window as the local template waveform. Further theoretical analysis and computer simulation show that, the acquisition time of proposed scheme is reduced significantly compared with conventional methods.