【作者】 张宇；

【导师】 张钦宇；

【作者基本信息】 哈尔滨工业大学 ， 通信与信息系统， 2006， 硕士

【摘要】 近几年来UWB技术已成为无线通信领域最热门的研究课题之一,同时也成为短距离高速无线通信协议标准争论的焦点。UWB信号的捕获与同步更是UWB系统中最为重要的部分之一,因此成为研究的热点。本文依托于国家自然科学基金重点项目“超宽带高速无线接入理论及关键技术”。由于UWB信号捕获的传统相关方法在FPGA中运算时间太长,并且对于高速的UWB信号,具有很大的时间不确定性,还有如此苛刻的捕获时间要求,所以有必要寻求一种更加有效的搜索算法。本文针对上述的不足提出了基于固定几何结构FFT(The Fast Fourier Transform)的UWB脉冲信号捕获算法的设计,并将其在FPGA中实现。本文的研究内容主要包括以下几个方面:(1)介绍UWB技术的基本原理,分析UWB信道对捕获算法设计的影响。(2)对基于快速傅立叶变换(FFT)的UWB信号相关捕获算法进行设计,讨论离散傅里叶变换算法及基2按时域抽取(Decimation In Time)的FFT算法,并且详细地介绍本文所要实现的基2固定几何结构的FFT算法的基本原理。(3)基于基2固定几何结构的FFT算法的基本原理提出了其高速流水线工作方式的实现方案,给出其MATLAB仿真过程及与传统FFT算法和MATLAB中的FFT函数仿真结果的比较。(4)对256点流水线工作方式固定几何结构的FFT算法在FPGA上进行设计,给出了包括整体实现电路以及主要模块电路详细设计过程,并通过波形仿真验证其功能,将仿真结果和MATLAB仿真结果进行比较,验证了设计方案的正确性及可行性。更多还原

【Abstract】 Recently UWB technology has become one of the hotest points of research on wireless communication, and the controversy focus on the standard of the protocol of short-range wireless communication. The acquisition and synchronization of UWB signal is one of the most parts in the system of UWB, so many people show great zeal for it.This dissertation is supported by National Natural Science Foundation of China“Key technology and theoretic of Ultra–Wideband wireless communications”. As the band-width of the UWB system increased, the very low pulse energy disperse to several ten even up to 100 dense paths, making the traditional correlator method take too long time to operate in FPGA, so here we consider that how to design a method of the acquisition and synchronization of UWB signal which based on fixed geometric structure FFT, and make it implement on the FPGA.Totally speaking, the dissertation includes the following parts:(1)It studied the basic theory of UWB, analyzed how the channel of UWB influence the UWB acquisition and synchronization system.(2)According to the characteristic of UWB channel, a method of the the acquisition and synchronization of UWB signal which based on the theory of FFT is disscussed.(3)On the foundation of the principle of fixed geometric structure FFT method, a high-speed and high-order pipeline method FFT is introduced and simulated in MATLAB.(4)According to the functional and technical requirements for the high-speed and high-order pipeline method FFT, the acquisition algorithm is implemented using FPGA, the design flow is given in detail, and the algorithm is validated the correctness and feasibility by comparing hardware timing simulation waveform with MATLAB simulation result.更多还原