认知跳频系统一体化平台研究与设计

发布时间：2019-01-01 13:51

【摘要】：针对传统跳频通信面临的挑战,以实时频谱感知为基础、动态频谱分配为过程和合理无线频谱管理为结果的认知无线电思想被创造性地与传统跳频有机结合在一起,发展成为全新的技术领域——认知跳频(Cognitive Frequency Hopping),该技术被认为是消除传统跳频系统用频困扰的有效途径之一。本文主要设计和实现了用于认知跳频系统的一体化平台,并且基于该平台对灵巧化频谱显示技术和常规谱估计宽带频谱感知算法进行了验证。首先,论文分析了跳频通信系统的研究背景、意义和应用现状,阐述了传统跳频通信系统遇到的频谱资源日益拥挤和用频设备剧增迫切需要实现频谱的高效利用、现有固定跳频体制无法适应高动态复杂突变电磁环境、恶劣频谱环境下多种类型的强干扰对传统跳频威胁日趋严重的困境,并由此引出认知跳频系统的概念;然后,论文给出了认知无线电技术和跳频通信系统的理论基础,并初步分析了认知跳频通信系统的优势;其次,论文结合认知跳频通信系统的频谱感知和定频/跳频通信两大基本功能,设计和实现了包含通信信道部分、感知信道部分、通信中频信号处理部分、频谱感知部分以及终端显示部分的一体化平台;再者,论文利用带通信号采样定理、正交下变频以及周期图功率谱估计等理论,完成了中频带宽和频率分辨率参数配置可选的灵巧化频谱显示功能,并给出了详细的数字信号处理流程和实测频谱显示效果图;最后,论文以一体化平台和灵巧化频谱显示为基础,研究了用于认知跳频的宽带频谱感知技术,论文选定基于常规谱估计的频谱感知算法用于跳频带宽内多干扰信号的感知,经过理论分析、仿真对比以及性能实测可知,该频谱感知算法可满足对认知跳频系统干扰态势进行准确分析的需求。
[Abstract]:Aiming at the challenge of traditional frequency-hopping communication, the cognitive radio thought, which is based on real-time spectrum sensing, dynamic spectrum allocation process and rational radio spectrum management, is creatively combined with traditional frequency hopping. Cognitive Frequency hopping (Cognitive Frequency Hopping), which has become a new technology, is considered to be one of the effective ways to eliminate the problem of frequency hopping in traditional frequency hopping systems. In this paper, an integrated platform for cognitive frequency hopping system is designed and implemented. Based on the platform, the smart spectrum display technology and the conventional spectrum estimation wideband spectrum sensing algorithm are verified. Firstly, this paper analyzes the research background, significance and application status of FH communication system, and expounds the urgent need to realize the efficient utilization of FH communication system, such as the increasingly crowded spectrum resources encountered by the traditional FH communication system and the sharp increase of frequency equipment. The existing fixed frequency hopping system can not adapt to the high dynamic and complex abrupt electromagnetic environment. Under the bad frequency spectrum environment, many kinds of strong interference are becoming more and more serious to the traditional frequency hopping threat, and the concept of cognitive frequency hopping system is introduced. Then, the paper gives the theoretical basis of cognitive radio technology and frequency hopping communication system, and analyzes the advantages of cognitive frequency hopping communication system. Secondly, combining the two basic functions of spectrum sensing and fixed frequency / frequency hopping communication in cognitive frequency hopping communication system, the paper designs and implements the communication channel part, the perceptual channel part, the if signal processing part. An integrated platform for spectrum sensing and terminal display; Furthermore, by using the theory of sampling theorem of bandpass signal, quadrature downconversion and power spectrum estimation of period diagram, the paper completes the flexible spectrum display function with the optional configuration of intermediate frequency bandwidth and frequency resolution parameters. The flow chart of digital signal processing and the effect chart of spectrum display are given. Finally, on the basis of integrated platform and dexterous spectrum display, broadband spectrum sensing technology for cognitive frequency hopping is studied. A spectrum sensing algorithm based on conventional spectrum estimation is selected to detect multi-interference signals in frequency-hopping bandwidth. Through theoretical analysis, simulation comparison and performance measurement, it can be seen that the spectrum sensing algorithm can meet the need of accurate analysis of interference situation in cognitive frequency-hopping systems.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN914.41

【相似文献】