摘要
激光测距以其高空间分辨率、高灵敏度、全天候等优良特性在主动遥感领域倍受青睐。激光测距仪的灵敏度(最大测程)主要取决于激光发射能量、有效接收光学孔径和系统信噪比。在激光发射能量和有效接收光学孔径受到限制的情况下,如何降低系统噪声,将微弱的激光脉冲信号从噪声中提取出来,成为至关重要的问题。从激光测距的原理出发,分析了各种微弱信号的检测方法,得出相关法是一种简单实用的方法。通过自相关与互相关的对比,决定采用模拟自相关法来进行微弱激光脉冲信号的检测。给出模拟自相关法检测电路并对其进行了试验。试验结果表明,使用模拟自相关法的最小信噪改善比为4.5,灵敏度为未经过模拟自相关检测的3.16倍。
Laser detection technology is widely applied in the field of active remote sensing because of its features of high space resolution, high sensitivity and all-weather capability. The sensitivity-the maximum distance measure-of laser range finder is depended on laser energy, available optical aperture and system SNR. If the laser energy and optical aperture are limited, how to reduce system noise and draw weak laser pulse signal from noise becomes extremely critical points. The principle of laser distance measure was illustrated and kinds of methods of weak signal detection were analyzed. The results show that analog self-correlation detection is a simple and effective method, better than cross-correlation detection. Analog self-correlation detection circuit was introduced and some experiments were made. The results demonstrate that the system minimum SNIR based on analog self-correlation detection is 4.5 and the sensitivity is 3.16 times of normal method.
出处
《红外与激光工程》
EI
CSCD
北大核心
2012年第10期2844-2847,共4页
Infrared and Laser Engineering
基金
国家973计划(2009CB724004)
