中文摘要：

强噪声背景下微弱特征信号检测,一直是工程应用领域的难题。系统地研究基于线性理论的时域、频域、时频域和基于非线性理论的微弱信号检测方法,分析各检测方法的基本原理和特点。时域检测法中主要分析相关检测、取样积分与数字式平均、时域平均检测法;频域检测法中分析最为常用的频谱分析法;时频分析法中主要分析应用范围最广的短时Fourier和小波变换;基于非线性理论的检测法中重点分析随机共振。分析认为基于非线性理论的微弱信号检测法、多种检测方法的结合是未来微弱信号检测的研究方向。

英文摘要：

Weak characteristic signal detection embedded in strong noise background is a difficult problem in engineering applications.In this paper,the methods of weak signal detection in time domain,frequency domain,time-frequency domain based on linear theory and non-linear theory,are systematically studied.The basic principles and characteristics of these methods are analyzed.In the methods of correlation detection in the time domain,sampling integral,digital averaging and time averaging are analyzed;while in the method of frequency domain detection,the widely used method of frequency spectrum analysis is studied.In the method of time-frequency domain analysis,the widely applied STFT and wavelet transformation are analyzed.The stochastic resonance is emphasized in the method based on the nonlinear theory.Finally,it is concluded that the methods of weak signal detection based on the nonlinear theory and combined methods may become a research concentration in the future.