【作者】 舒畅；

【导师】 裴承鸣；

【作者基本信息】 西北工业大学 ， 人机与环境工程， 2004， 硕士

【摘要】 非平稳信号分析是现代数字信号处理的重要分支之一，而基于二维时频空间的时频分析方法是研究该类信号的有效工具，其中，如何对信号特征进行自适应跟踪描述是一个难点，同时也是一项具有积极学术意义和明确应用价值的探索性课题。本文在系统学习现有时频分析方法的基础上，详细研究了自适应时频分析的核心思想和基本方法，基于自适应信号展开理论和自适应滤波理论，提出了自适应Chirplet和自适应递推时频分析这两种新的非平稳信号处理方法，并通过理论分析和数值仿真研究了两种方法和算法的数值与应用特性。结果表明，所研究的方法在时频分辨能力、抗噪性等方面具有明显的优势。 作为一种特殊的振动形式，颤振与飞行器的运行环境和安全性密切相关，是人机与环境学科的一个重要研究课题。本文基于颤振试验信号的非平稳特点与分析需求，应用自适应时频分析技术给出并实现了两种新的颤振信号处理方案，重点研究了适用于连续变速颤振试验的颤振边界预测问题。并通过数值仿真和某型飞机气弹模型低速风洞颤振试验验证了方案的有效性、可靠性和工程实用性。 本文相关数值仿真与实时分析软件基于LabVIEW虚拟仪器集成环境设计开发。更多还原

【Abstract】 Time-frequency analysis represents simultaneously the energy or intensity of signal in time and frequency. It’s of great significance how to adaptively describe a signal in time-frequency domain. In this thesis, the theory of time-frequency analysis, especially adaptive time-frequency analysis is considered. Two new methods of adaptive time-frequency analysis are proposed based on adaptive signal expansion and adaptive filtering. The characteristics of the two methods are studied by numerical simulation. The results show that both the methods are reasonable and feasible.As a special form of vibration, flutter is a major feature closed with the run environment and safety of aircraft, which is an important project of Human-Machine-Environment Engineering. Focused on the nonstationary features and analysis requirements of flutter test data, the application scheme is brought forward for flutter signal processing. By using computer simulation and flutter test of low-speed wind-tunnel of some aeroelastical modes, the characteristics of the scheme are investigated. Especially, the technique proposed here can be expanded to the flutter test with variable speed.The related software is developed on LabVIEW for Windows.更多还原