改進(jìn)非平穩(wěn)信號(hào)的分析方法

研究了WVD和短時(shí)傅里葉變換兩種時(shí)頻分析方法的優(yōu)勢(shì)和局限性，從兩種方法的定義出發(fā)，分析了兩者間存在的聯(lián)系，通過(guò)構(gòu)造窗函數(shù)，提出一種改進(jìn)的非平穩(wěn)信號(hào)分析方法，并進(jìn)行了相應(yīng)的計(jì)算機(jī)仿真，結(jié)果表明信號(hào)的時(shí)頻特性得到了改善，該方法還適用于多分量非平穩(wěn)信號(hào)的分析。
關(guān) 鍵 詞 時(shí)頻分布; 非平穩(wěn)信號(hào); 調(diào)頻信號(hào); 參數(shù)估計(jì)

Abstract Wigner ville distribation and short time Fourier transform are the main time-frequency analysis methods. However, both of them have their advantages and limitations. On the base of the definition of the two transform, this paper analyzes the connection between them, then proposes an improved method through the construction of window function. Computer simulation shows the time-frequency character of signal is improved and the method is applicable to the analysis of multicomponent nonstationary signal.
Key words time-frequency distribution; nonstationary signal; frequency-modulated signal; parameter estimation