摘要
为了解决远程激光测距回波信号信噪比低、信号难以检测的问题,提出了一种基于EMD的小波阈值去噪方法。首先,将脉冲回波信号通过EMD算法分解为频率从高到低的不同分量;其次,对高频分量进行小波阈值去噪处理,提出了一种阈值改进方法,从而提高了信噪比;最后,将去噪后的信号进行峰值检测,定位回波脉冲的峰值所在位置。通过matlab仿真,验证了文章所提出方法的有效性。结果显示,该方法可以将激光回波信噪比从-15dB提高到2.66dB,采用200Msps的AD进行采样,定位目标误差可控制在1.5m以内。
In order to solve the problem that the signal to noise ratio（SNR） of the remote laser ranging echo signal is low and the signal is difficult to detect, a wavelet threshold denoising method based on EMD is proposed. Firstly, the pulse echo signal is decomposed into different components of frequency from high to low by EMD algorithm. Secondly, wavelet threshold denoising is applied to high frequency components, and a threshold improvement method is proposed to improve the signal-to-noise ratio. Finally, the denoised signal is subjected to peak detection to locate the peak of the echo pulse.The validity of the proposed method is verified by matlab simulation. The results show that the proposed method can achieve the laser echo target with SNR of -15 dB, and the SNR is increased to 2.66 dB. The sampling error of the target is controlled within 1.5 m.
出处
《信息通信》
2018年第1期48-50,共3页
Information & Communications
关键词
激光测距
低信噪比
EMD
小波阈值去噪
峰值检测
laser ranging
low signal- to-noise ratio
EMD
wavelet threshold denoising
peak detection
