基于Davis-Smith方法计算卫星磁强计零位补偿的误差特征研究

卫星所携带的磁通门磁强计会随时间发生零位漂移，因此需要对其进行补偿.基于行星际磁场的剪切阿尔芬波动特性，利用Davis-Smith方法可计算磁强计的零位磁场.本文利用数值模拟，分析了总磁场幅度B_T及压缩波动对Davis-Smith方法所产生零位补偿的误差特征.我们发现，B_T越大，零位补偿误差越大；且当压缩波动频率和剪切波动频率不同时，磁场各分量的零位补偿之间的比值与对应背景磁场的比值近似相等；压缩波动的幅度越小，零位补偿的误差趋于更小；此外，压缩波动的频率和初始相位等也会影响零位补偿的误差.这些误差特征可为提高零位补偿的可靠性提供重要的理论依据.

Error properties of the fluxgate magnetometer offset based on Davis-Smith method

There is a zero level drift for the fluxgate magnetometer carried by a satellite over time, so the magnetometer needs to be compensated. Based on the characteristics of the Alfvén fluctuation of the interplanetary magnetic field, the Davis-Smith method can be used to calculate the zero level of the magnetometer. In this paper, we use the numerical simulation to analyze the error characteristics of the zero level, which calculated by the Davis-Smith method, caused by the total magnetic field amplitude B_T and the compressional fluctuation. We find that the larger the B_T is, the greater the error of the zero level is. When there is a difference of the frequencies between the compressional and Alfvén fluctuations, the ratio between the zero level offsets of any two components of the magnetic field is approximately equal to the ratio of the corresponding background magnetic field. The error of the zero level tends to be smaller when the amplitude of the compressional fluctuation is smaller. In addition, the frequency and initial phase of the compressional fluctuation can also affect the error of the zero level. These error characteristics can provide important theoretical basis for improving the reliability of the zero level offset.