步进频率激光雷达测距信号处理技术研究  

Research on signal processing technology of stepped frequency lidar ranging

作　　者：田丰宇 冯振中[1] 尹微 童文皓 周鼎富[1] TIAN Fengyu;FENG Zhenzhong;YIN Wei;TONG Wenhao;ZHOU Dingfu(Southwest Institute of Technical Physics,Chengdu,610041,China)

机构地区：[1]西南技术物理研究所,成都610041

出　　处：《激光杂志》2023年第6期24-29,共6页Laser Journal

基　　金：四川省科技计划资助(No.2022YFG0352)。

摘　　要：文中介绍了雷达系统步进频率(Stepped-Frequency,SF)信号的模型,研究了非相参激光雷达采用步进频率信号方式测距的问题。仿真研究了各阶梯脉冲回波信号相位关系不确定和信噪比对测距的影响,提出消除相位影响的方法,并应用在固定目标实测试验中。试验采用频率步进量1 MHz、调频范围80 MHz正弦波调制声光晶体产生步进频率激光脉冲序列,使用采样率40 Msps的ADC采集激光回波并处理,对489.2 m的标定目标测量精度达到1.17 m。在低信噪比时,采用多组脉冲串累积方式仍能求得目标距离值。此研究实现低采样率下固定目标的高精度测距,为步进频率信号处理方式高精度激光相干测距产品的研制打下坚实基础。In this paper,the model of the SF signal of the radar system is introduced,and the problem of non-coherent lidar ranging by SF signal is studied.The influence of uncertainty of phase relationship and signal-to-noise ratio of each step pulse echo signal on ranging is simulated,and a method to eliminate the influence of phase is proposed,which is applied in the actual measurement test of fixed target.In the test,a sine wave modulated acousto-optic crystal was used to generate a SF laser pulse sequence,and an ADC with a sampling rate of 40 Msps was used to collect and process the laser echoes,and the measurement accuracy of the 489.2 meters calibration target reaches 1.17 m.When the signal-to-noise ratio is low,the target distance value can still be obtained by using the multigroup pulse train accumulation method.This research achieves high-precision ranging of fixed targets at low sampling rates,and lays the foundation for the development of high-precision laser coherent ranging products with SF signal processing.

关 键 词：激光测距 步进频率信号 相位 信号处理 

分 类 号：TN249[电子电信—物理电子学]