水下地磁导航技术中的地磁场空间差分测量方法

摘要

In order to accurately measure the geomagnetic field around an underwater vehicle and improve the precision of geomagnetic aided navigation,a spatial difference measuring method is proposed based on multi-sensor.First,a new measurement model of magnetic vector sensors is established by analyzing the magnetic field types and the spatial distribution characteristics around the vehicle.Then,the spatial difference model expression is deduced according to the characteristics of interference magnetic field and its coupling relationship with the magnetic field.The proposed method was compared with traditional method by simulation and ground experiment.Results show that the proposed method can obviously restrain the impact of the interference magnetic field.When the intensity of the outside interference magnetic field is 1000 nT,the measurement error can be controlled under 150 nT by the spatial difference measuring method,which is able to improve the ability of anti-jamming in geomagnetic field measurement.%为了实现水下载体对地磁场的精确测量,提高地磁辅助导航的精度,提出了一种基于多传感器的空间差分地磁场三分量测量方法.首先,分析了水下载体周围磁场的种类及空间分布特性,并建立了磁矢量传感器新的测量模型.然后,利用干扰磁场自身特性以及和地磁场之间的耦合关系构建方程组,推导出空间差分模型表达式.最后,通过仿真分析和地面实验分别将本文方法与传统测量方法进行了对比.结果表明:当外界干扰磁场为1000 nT时,差分测量结果能使测量误差控制在150 nT以内,很好地抑制了干扰源对地磁场测量造成的影响,提高了水下载体地磁场三分量测量的抗干扰能力.