Attitude-Independent Magnetometer Calibration with Time-Varying Bias

We present a method for on-orbit, attitude-independent magnetometer calibration that includes the effect of time-varying bias due to electronics on-board a spacecraft. The calibration estimates magnetometer scale factors, mis-alignments, and constant as well as time-varying bias. Time-varying effects are mitigated by including spacecraft telemetry in the measurement model and estimating constant parameters that map the telemetry data to magnetometer bias. The calibration is demonstrated by application to flight data from the Radio Aurora Explorer satellite and significantly reduces the uncertainty of off-the-shelf magnetometers embedded within the satellite and subject to spacecraftgenerated fields. This method simplifies the satellite design process by reducing the need for booms and strict magnetic cleanliness requirements.