LFMCW激光雷达二次混频变周期调频解耦算法  

Secondary mixing varied period FM decoupling method for LFMCW Lidar

作　　者：王俏 杜小平 王建争 

机构地区：[1]装备学院航天装备系,北京101416

出　　处：《信息与电子工程》2012年第3期325-329,共5页information and electronic engineering

摘　　要：线性调频连续波(LFMCW)激光雷达探测多个运动目标时,不同目标的中频信号频谱会相互叠加,此时无法直接从中频信号的频谱获取每个目标的距离和速度信息。为此提出一种基于二次混频和变周期调频解耦的多目标检测算法,用于LFMCW激光雷达多目标探测情况下目标检测与信息获取。该方法利用中频信号二次混频获得目标的多普勒频移,然后通过变周期调频对不同调频斜率下目标多普勒频移进行配对,获得真实目标的多普勒频移。利用所获得目标速度信息构建补偿信号对原中频信号进行补偿,并最终获得目标的距离信息。利用该方法对包含3个不同目标的中频信号进行检测仿真,获得3个目标的速度误差分别为:2.67%,1.01%以及0.01%,测距误差分别为0.10%,0.19%和0.28%。仿真结果说明该方法可以有效检测多个运动目标,并具有较高的检测精确度。When Linear Frequency Modulated Continuous Wave（LFMCW） Lidar detecting several moving targets, IF signals of different targets are superimposed. The range and speed of targets could not be observed from the IF signal spectrum. A new multi-target detection method based on secondary mixing and varied period FM decoupling for LFMCW Lidar is presented in this paper. Doppler frequency is obtained by secondary mixing of IF signalthrough this method. Then the targets＇ Doppler frequency is matched by varied period FM at different chirp rates to eliminate false signal and obtain the speed of targets. The speed information is used to build the compensation signal for the original IF signal in order to obtain the range information of targets. An IF signal containing three different targets is simulated by this method. Target speed errors in the simulation are 2.67%,1.01% and 0.01% respectively, while target range errors 0.10%,0.19% and 0.28%. Simulation results indicate that the new method can obtain the information of multi-target with high accuracy.

关 键 词：线性调频连续波 多目标检测 运动补偿 变周期调频 

分 类 号：TN958.98[电子电信—信号与信息处理]