以研究瞬态电磁辐射信号的远距离探测手段为目的,得到了适用于高频瞬态信号的改进双耦合Duffing振子自适应检测算法。首先分析了双耦合Duffing系统对瞬态放电信号的检测性能,发现该系统对高频信号的检测灵敏度较差,且背景噪声会影响系统的同步效果,导致目标信号误判。基于此对系统算法进行了改进,引入了信号变尺度处理和自适应调节驱动力幅值的算法,利用仿真以及实验验证了该系统的可行性。仿真及实验结果表明,在微弱窄带信号及高斯噪声的干扰下,检测算法能将信噪比<–20 d B的放电信号检测出来;且当信噪比>–20 d B时,系统的检测概率能>90%,检测信噪比<–20 d B时,系统的虚警概率控制为<1%,能够满足工程应用中对检测概率的需求。可见改进算法能够克服双耦合Duffing振子模型存在的弱点,通过待检信号展宽及自动调节驱动力幅值,得到最佳系统检测态,将淹没在背景噪声中的瞬态电磁辐射信号检测出来,为进一步远距离探测的工程应用提供了理论指导。
【英文摘要】
To investigate the remote detection method of transient electromagnetic signals, the detection method based on adaptive double coupled Duffing oscillators is improved, which is applied to high frequency transient signals. At first, the detection performance of double coupled Duffing oscillators is analyzed. It is found that the system detection sensitivity is weak for high frequency signals and the background noises will disturb the synchronization which leads to mistake in estimating the target signal. Hen...