基于互素亚奈采样的宽带频谱感知理论与技术研究

Nowadays, the problem of spectrum overcrowding heavily hinders the service expansion of Internet of things, mobile communication, broadcasting television, wireless LAN etc. Meanwhile, how to effectively, accurately achieve wireless wide band spectrum sensing with a low sampling cost has been a focusing task in both scholar field and engineering field. To overcome drawbacks of the existing spectrum holes detection methods i.e., lack of abundance of the theoretic analysis tools, high cost of compressive sampling, singleness of spectrum reconstruction means etc., this project proposes a novel scheme incorporating the Chinese Remainder Theorem, co-prime undersampling and phase spectrum reconstruction. This project consists of the following topics: 1) Combining the features of wireless wide band signals and properties of co-prime spectra, we shall design blind detection scheme capable of removing spurious effects and cross-term intererences; 2) Utilizing the prior knowledge of the bandwidth and sparse distribution of wireless signals, we shall design non-blind detection scheme capable of rapidly sensing wireless wide spectra; 3) Through incorporating the new achievements of Chinese Remainder Theorem, we shall develop a novel structures of wide band co-prime spectrum analysis which relaxes the hardware conditions of ADC compressive sampling; 4) In combination with all-phase spectral analysis and all-phase filtering, we shall develop techniques to improve the performance of co-prime spectral analysis on wide band wireless signals. In general, this project will establish a novel knowledge system of co-prime spectrum sensing of wireless wide band signals, including fundamental theory, algorithm design, simulation and experimental verification.

当前，频谱拥塞问题严重阻碍了物联网、移动通信、广播电视、无线局域网等业务的拓展， 而如何高效、高精度且以低欠采样硬件成本地实现无线宽带的频谱感知，是学术界和工程界有待突破的课题。针对现有检测频谱空洞方法存在理论分析工具不丰富、压缩欠采样成本高、谱重构手段单一的不足，本课题分别提出引入中国余数定理、互素欠采样、相位谱重构方法做改进，拟在以下4个方面展开研究：1)结合无线宽带信号特点和互素谱性质，设计可消除伪峰效应和交叉项干扰的互素谱盲检测方案； 2)针对宽带信号的子带带宽和稀疏分布等先验知识，设计可快速感知无线宽带谱的非盲检测方案；3) 利用中国余数定理的新成果，设计允许放宽ADC压缩采样硬件条件的新型宽带信号互素谱分析结构；4)结合全相位谱分析与滤波理论，改进欠采样宽带信号的互素谱感知的性能。最终建立一套包括基础理论、算法设计、仿真与实验验证的新型宽带互素谱感知的知识体系。

当前，频谱拥塞问题严重阻碍了物联网、移动通信、广播电视、无线局域网等业务的拓展， 而如何高效、高精度且以低欠采样硬件成本地实现无线宽带的频谱感知，是学术界和工程界有待突破的课题。针对现有检测频谱空洞方法存在理论分析工具不丰富、压缩欠采样成本高、谱重构手段单一的不足，本课题分别提出引入中国余数定理、互素欠采样、相位谱重构方法做改进，在如以下4个方面展开研究：1)完善了互素谱分析的核心组成部件--全相位滤波器设计的理论工作，设计出一系列具有解析表达式，无需迭代复杂.的全相位滤波器； 2)设计可消除伪峰效应和交叉项干扰的互素谱盲检测方案和非盲检测方案，并且通过仿真验证其可行性； 3)在空间互素谱分析方面，提出并仿真实现了一系列基于协方差矩阵映射的DOA估计方法；4) 在无源被动互素谱分析方面，提出并仿真实现验证了基于松弛互素阵列的入射载频和空间入射角联合估计方法，为当前电子战无源目标感知提供了新型的理论支撑；最终建立一套包括基础理论、算法设计、仿真与实验验证的新型宽带互素谱感知的知识体系。