基于信号预处理的杜芬振子弱信号检测方法

杜芬振子对周期信号极其敏感,对噪声具有较强免疫力,被研究用于强噪声背景下弱周期信号的检测及其各项参数的测量。为进一步提高杜芬振子检测含噪信号的性能，本文提出了先对待测信号预处理再送入杜芬振子的弱信号检测算法，并在理论上进行了证明。该方法先将待测信号分割、叠加、延拓再送入杜芬振子进行检测，仿真表明该方法在将信号分割成多段、叠加、延拓时可获得较大的信噪比增益，其中分割数目为3时，检测信噪比下限降低约为2 dB，分割数目为5时，检测信噪比下限降低约为3 dB。

Duffing oscillator weak signal detection method based on Signal preprocessing

Duffing oscillator is extremely sensitive to the periodic signal and has strong immunity to noise. So it is used for the detection of weak periodic signal in strong noise background and the measurement of its parameters. In order to further improve its detection performance, a new method of Duffing oscillator weak signal detection based on signal preprocessing is proposed and is proved in theory. The new method firstly processes the signal by segmentation, stacking, extension then sends the processed signal to Duffing oscillator to detect. Simulation results show that the proposed method can obtain a large SNR gain, when the segmentation number is three, the lower limit of detection SNR reduces about 2dB, when the number of segmentation is five, the lower limit of detection SNR reduces about 3dB.