Magnetic gradiometry using frequency-domain filtering
Name
Ream_2022_Meas._Sci._Technol._33_015104.pdf
Description
Published version
Size
3.5 MB
Format
Adobe PDF
Checksum (MD5)
9292d32bbf28cadabf8d31bed021943d
Author(s)
Ream, Jodie B
Weiss, Benjamin P
Oran, Rona
Raymond, Carol A
Polanskey, Carol A
Wenkert, Daniel D
Elkins-Tanton, Linda T
Hart, Richard A
Russell, Christopher T
Merayo, Jose MG
Date Issued
2022
Journal
Measurement Science and Technology
Publisher
IOP Publishing
Citation
Ream, Jodie B, Weiss, Benjamin P, Oran, Rona, Raymond, Carol A, Polanskey, Carol A et al. 2022. "Magnetic gradiometry using frequency-domain filtering." Measurement Science and Technology, 33 (1).
Version
Final published version
Abstract
Abstract
Accurate measurements of ambient planetary and interplanetary magnetic fields using spacecraft magnetometers typically require accounting for interfering magnetic fields generated by the flight system (FS). The most common method for removing FS-generated time-variable magnetic fields is narrow-band and low-pass filtering of magnetic field data in the frequency domain. However, if fluctuations in the ambient field contain frequencies overlapping those in the FS field, it can be difficult to construct a filter that will not affect both signals. Here we present an alternate method for removing FS time-variable signatures from magnetic field measurements. For spacecraft that make use of a magnetic gradiometer (i.e. with two or more instruments on a boom at different distances from the center of the spacecraft), the dominant frequencies in the FS field can be identified using spectra of the differenced field components. The amplitudes of the FS field at those frequencies can then be suppressed without removing spectral peaks present in the ambient field. We demonstrate the successful application of this method, referred to as gradiometry peak suppression, both to modeled data sets and to 128 Hz Venus Express magnetometer data.
Accurate measurements of ambient planetary and interplanetary magnetic fields using spacecraft magnetometers typically require accounting for interfering magnetic fields generated by the flight system (FS). The most common method for removing FS-generated time-variable magnetic fields is narrow-band and low-pass filtering of magnetic field data in the frequency domain. However, if fluctuations in the ambient field contain frequencies overlapping those in the FS field, it can be difficult to construct a filter that will not affect both signals. Here we present an alternate method for removing FS time-variable signatures from magnetic field measurements. For spacecraft that make use of a magnetic gradiometer (i.e. with two or more instruments on a boom at different distances from the center of the spacecraft), the dominant frequencies in the FS field can be identified using spectra of the differenced field components. The amplitudes of the FS field at those frequencies can then be suppressed without removing spectral peaks present in the ambient field. We demonstrate the successful application of this method, referred to as gradiometry peak suppression, both to modeled data sets and to 128 Hz Venus Express magnetometer data.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1088/1361-6501/AC2E2E
