基于混沌振子微弱信号检测的改进与比较

Improvement and comparison of weak signal detection based on chaotic oscillator

为实现强噪声背景下微弱信号的检测,利用混沌系统非平衡相变对系统参数的扰动和对噪声具有免疫力的特点,根据Holmes型的Duffing振子检测系统的检测原理以及Melnikov方法,对Duffing方程的非线性项进行了改进,非线性项取(-x3+x5)。改进后的系统相对原来的检测系统具有更低的信噪比门限,由原来的-92.5 dB降到了-111.5 dB。数值计算与仿真结果证明了该方法的有效性。

Aiming at realizing weak signal detection in strong noise background, using the character with chaotic system＇s nonbalance phase transition parameter disturbance and immunity about noise, Holmes Duffing oscillator detection system＇s principle and Melnikov method were recommended. The non-linear part of Duffing equation was improved, and the non-linear was（ -x^3 ＋ x^5 ）. The improved system has a lower signal to noise ratio threshold than the original detection system, which is - 111.5 dB as before is -92.5 dB. The numerical simulation results prove that this method is effective.