OFDM-UWB系统压缩采样技术研究

发布时间：2018-04-08 22:02

  本文选题：超宽带　切入点：正交频分复用　出处：《天津工业大学》2017年硕士论文

【摘要】：超宽带作为5G应用场景之一,OFDM-UWB系统作为主流的超宽带系统,备受学者们研究。UWB技术因其超高带宽,带来高速采样问题,严重制约其发展。本文将压缩感知理论应用在OFDM-UWB系统,去解决超宽带系统的高速高精度ADC问题,实现OFDM-UWB信号的低速低精度采样。针对OFDM-UWB系统的高速采样问题,对现有模拟信号压缩采样方法的适用性进行分析,在建立分段观测模型的基础上提出基于哈达码矩阵的优化并行分段压缩采样(the Optimized Parallel Segmented Compressed sampling,OPSCS)方案。利用哈达码矩阵构造任意维度分段观测矩阵,从而得到正交或准正交的多路观测序列,改善了有限等距特性。采用简化的正交匹配追踪算法,避免迭代运算。研究表明,该方法可有效实现OFDM-UWB系统的压缩采样,同时具备良好的抗噪声能力,从而达到比现有压缩采样乃至奈奎斯特速率采样均优越的系统性能。考虑量化的情况下,对OFDM-UWB系统高速高精度ADC问题,首先对OFDM信号量化噪声模型进行分析,分析了传统的单零点和多零点∑△调制器在OFDM信号中的应用,基于压缩感知的随机解调结构,提出了随机解调∑ △量化压缩采样结构。通过仿真实验比较了传统单零点∑ △调制器和多零点∑ △调制器在OFDM信号应用的性能,比较了本文提出的结构与多零点∑ △调制器在OFDM信号应用的性能。仿真表明了多零点∑ △调制器性能明显比单零点∑ △调制器性远远要好,在相同的ADC采样速率下,本文提出结构随机解调∑ △量化压缩采样结构的性能要远远好于多零点∑ △调制器性能。
[Abstract]:Ultra-wideband (UWB) as one of the 5G application scenarios, OFDM-UWB system as the mainstream of ultra-wideband system, has been studied by scholars because of its ultra-high bandwidth, resulting in high-speed sampling problem, which seriously restricts its development.In this paper, the theory of compression sensing is applied to OFDM-UWB system to solve the problem of high speed and high precision ADC in UWB system, and to realize the low speed and low precision sampling of OFDM-UWB signal.Aiming at the problem of high speed sampling in OFDM-UWB system, the applicability of existing analog signal compression sampling methods is analyzed. Based on the establishment of segmented observation model, an optimized parallel piecewise compression sampling scheme based on Hada code matrix is proposed for the Optimized Parallel Segmented Compressed sampling OPSCS.An arbitrary dimensional piecewise observation matrix is constructed by using the Hadad code matrix, and the orthogonal or quasi-orthogonal multipath observation sequence is obtained, which improves the finite equidistant characteristic.A simplified orthogonal matching tracking algorithm is used to avoid iterative operation.The research shows that the proposed method can effectively realize the compression sampling of OFDM-UWB system and has good anti-noise capability, which is superior to the existing compression sampling and even Nyquist rate sampling.In the case of quantization, the quantization noise model of OFDM signal is analyzed for the ADC problem of high speed and high precision in OFDM-UWB system. The application of traditional single zero and multi-zero 鈭，

本文编号：1723524