半航空瞬变电磁干扰特征与降噪研究  

Study on semi-airborne transient electromagnetic interference characteristics and noise reduction

作　　者：向锡斌 李海侠[1] 刘慧鹏 XIANG Xibin;LI Haixia;LIU Huipeng(School of Land and Resource Engineering,Kunming University of Science and Technology,Kunming,650031;China Nonferrous Metals Industry Kunming Survey,Design and Research Institute Limited,Kunming,650216)

机构地区：[1]昆明理工大学国土资源工程学院,昆明650031 [2]中国有色金属工业昆明勘察设计研究院有限公司,昆明650216

出　　处：《地质论评》2024年第6期2281-2294,共14页Geological Review

基　　金：国家自然科学基金资助项目(编号:42064005)的成果。

摘　　要：为了验证多旋翼无人机在半航空瞬变电磁勘探作业中产生的电磁干扰影响,笔者等开展了一系列实验,包括在无人机不同工作状态下进行时频噪声分析,以及研究噪声源与接收点之间距离对噪声水平的影响。实验发现,大疆T20无人机电机转动产生的周期性电磁干扰频段在550~900 Hz,当接收线圈与无人机的距离为10 m时此干扰可被忽略。针对剩余的其他噪声,笔者等提出了基于移动窗口的递归最小二乘法自适应降噪方法。通过降噪实验,验证了该方法能够有效压制干扰,还原出信号的原始特征。将此降噪方法应用于香格里拉安乐铅锌矿实测半航空瞬变电磁信号处理,取得了显著的降噪效果。Objectives:To verify the electromagnetic interference effects of multi-rotor UAV in semi-airborne transient electromagnetic exploration,and develop effective noise reduction methods to improve the quality of exploration signal data.Methods:The time-frequency noise analysis is carried out to detect the electromagnetic interference generated by multi-rotor UAV(taking DJI T20 as an example)under different working conditions.The influence of the distance between the noise source(UAV)and the receiving point on the noise level is studied.A recursive least square method based on moving window is proposed and applied.Results:It is found that the main frequency band of periodic electromagnetic interference generated by motor rotation of DJI T20 UAV is 550~900 Hz.When the distance between the receiving coil and the UAV is 10m,the above interference can be ignored.Noise reduction experiments prove that the proposed adaptive noise reduction method can suppress the interference effectively and restore the original characteristics of the signal.Conclusions:It is proved by experiments that the electromagnetic interference of multi-rotor UAV in semiairborne transient electromagnetic exploration can be observed,especially at close range.By applying recursive least square method based on moving window,the electromagnetic interference generated by UAV can be effectively reduced and the original characteristics of the disturbed signal can be restored.The application of the noise reduction technology to actual geological exploration data processing can significantly improve the data quality,and is conducive to further geological interpretation and mineral resource evaluation.

关 键 词：半航空瞬变电磁法 多旋翼无人机 噪声分析 降噪处理 递归最小二乘法 移动窗口 

分 类 号：P631.326[天文地球—地质矿产勘探]