【作者】 荆利明；

【导师】 汪一鸣；

【作者基本信息】 苏州大学 ， 通信与信息系统， 2008， 硕士

【摘要】 超宽带(UWB)无线通信技术具有传输速率高、功耗低、定位精度高、抗多径能力强等许多优点,已成为短距离无线通信领域研究与开发的热点。但是超宽带技术要走向成熟,还需要解决许多关键的技术问题,其中之一就是信号的同步问题。由于超宽带信号直接使用基带传输亚纳秒级的极窄脉冲,并且由于功耗的限制,信号淹没在噪声之中,同时又有本系统多用户干扰和其他窄带系统信号的干扰,接收信号如何准确同步就成为难点之一。本文以UWB通信系统为背景,主要研究了UWB系统中同步捕获问题,提出了实现方案并予以仿真实现。首先介绍了超宽带通信的发展动态、基本原理,深入研究了典型的UWB通信系统方案及其调制技术,讨论了UWB通信的信道模型。接下来讨论了UWB系统的各种同步技术,最后分别提出了一种适用于DS-UWB系统的采用TDT算法与滑动相关相结合的同步捕获方案,以及一种适用于TH-UWB系统的基于跳时码整体同步的TH-UWB多用户系统同步方案,并通过仿真验证了这两种同步捕获方案用于UWB系统的可行性。更多还原

【Abstract】 Since the Ultra Wideband (UWB) wireless communication has lots of advantages such as high data transmission rate, low power consumption, high precision location identification and inherently exceptional multipath immunity and so on, it has been the subject of extensive research in the short-range wireless communication area. But there are still some key problems need to be solved before the UWB technology comes into actual use, and one of these key points is synchronization. Since the carrier-less UWB system transmits the base-band, extremely narrow impulses on the sub-nanosecond order directly, the transmitted signals will hide in the noise environment due to the limitation of the signal power. And there exist multi-user interference from the system itself and the other narrowband systems. Accurate synchronization becomes one of the difficult techniques.The subject of this thesis is the synchronization capture technology in UWB. And some realization scheme are proposed and simulated in this thesis. The basic theory of UWB communication is introduced at first. The system model and the modulation technology is then analyzed in detail, also the UWB channel model is discussed. Many synchronization schemes are illustrated and compared in succession. Finally two schemes are proposed, one is the improved Timing with Dirty Templates (TDT) coarse synchronization combined with slide correlation fine synchronization scheme used in the multi-user Direct Sequence spread spectrum UWB (DS-UWB), and the other is the synchronization scheme based on the entire Time Hopping (TH) code in the multi-user TH-UWB system. The simulation results show those two algorithms can capture the synchronization time in the UWB system efficiently.更多还原