基于压缩采样∑Δ调制的OFDM-UWB基带关键技术研究

项目名称： 基于压缩采样∑Δ调制的OFDM-UWB基带关键技术研究

项目编号： No.61302062

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 戈立军

作者单位： 天津工业大学

项目金额： 25万元

中文摘要： 高速高精度采样是超宽带（UWB）通信系统的主要技术瓶颈，压缩感知（CS）理论为解决这一难题提供了契机。本项目针对OFDM-UWB系统，在前期研究无过采样∑Δ调制（Nyquist-∑Δ）的基础上，首先引入CS理论研究一种基于压缩采样的∑Δ调制（CS-∑Δ）技术。在发送端提出压缩采样编码级联∑Δ调制（CSC-∑Δ）结构，在接收端提出∑Δ解调级联压缩采样重建（∑Δ-CSR）结构，从而实现系统低于奈奎斯特速率的单比特数模模数转换，从速度和位宽两方面降低采样实现难度。单比特量化亦能同时解决系统高峰均比问题。其次，本项目将研究适于该CS-∑Δ系统的高效时频同步技术，特别提出一种无导频盲频率跟踪算法。最后，基于FPGA构建基带处理实验平台，对系统性能进行验证评估。本项目有利于从根本上克服UWB系统的技术瓶颈，建立基于CS-∑Δ调制的高性能基带处理体系，为加速我国高速UWB通信技术的发展奠定理论基础。

中文关键词： 压缩采样；∑Δ调制；正交频分复用；超宽带；同步

英文摘要： High-speed high-precision sampling is a major technical obstacle in implementation of ultra-wideband (UWB) communication systems. By using the theory of compressive sensing (CS) it now gives us an opportunity to solve this problem. On the basis of the preliminary research of a non-oversampled ΣΔ modulation (Nyquist-ΣΔ), the project firstly introduces the CS theory and researches on a CS based ΣΔ modulation (CS-ΣΔ) technology for OFDM-UWB systems. It proposes a structure that cascades the compressive sampling coding and the ΣΔ modulator (CSC-ΣΔ) in the transmitter, and a structure which cascades the ΣΔ demodulator and the compressive sampling reconstruction (ΣΔ-CSR) in the receiver. It can achieve sub-Nyquist-rate single-bit digital-to-analog and analog-to-digital conversion of the system, and reduces the sampling implementation difficulty in both aspects of speed and bandwidth. Single-bit quantization can also solve the high peak-to-average ratio problem of the system at the same time. Secondly, the project researches on high-performance time and frequency synchronization technologies, which apply to the CS-ΣΔ system, and especially provides a non-pilot-aided blind frequency tacking algorithm. At last, it builds a baseband processing experimental platform based on FPGA, and verificate and assess the system perfo

英文关键词： compressive sampling；∑Δ modulation；OFDM；UWB；synchronization