MMS 3 DSP Search Coil Magnetometer: Magnetic Field Power Spectral Density, 16 s Data

NASA's Magnetospheric Multiscale (MMS) mission provides magnetic field power spectral density (BPSD) data computed onboard by a Digital Signal Processor (DSP). The data is derived from Search Coil Magnetometer (SCM) signals using a 1024-point FFT algorithm, producing spectra with 88 pseudo-logarithmic frequency bins and a dynamic range over 120 dB. The dataset was last updated on March 13, -2026.

Use Cases

• Analyzing plasma wave emissions based on the 88 pseudo-logarithmic frequency bins.
• Determining plasma density from narrow-band emissions with an accuracy of (del f)/f ~3%.
• Studying magnetic field fluctuations using power spectra averaged over time, from 16 per second to one every 16 seconds.
• Investigating signal dynamics across nine simultaneously processed channels, including DC-coupled and AC-coupled signals.

Strengths

• Data is computed onboard using a dedicated Digital Signal Processor (DSP) and a 1024-point FFT algorithm.
• Spectra are reduced to 88 frequency bins with (del f)/f between 6% and 12%, allowing for detailed frequency analysis.
• The averaging process uses 48-bit accuracy to maximize dynamic range, and amplitudes are compressed to an 8-bit number representing over 120 dB of dynamic range.

Limitations

• Timing between channels can be inaccurate by a fraction of a second as components are not synchronized to the 1-second pulse.
• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and file formats are unknown, which may limit suitability assessment.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Data computed onboard the MMS spacecraft by a Digital Signal Processor (DSP) from Search Coil Magnetometer (SCM) analog signals.

Time Range

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Freshness

Last updated 2026-03-13 06:10:14.630780; freshness should be verified.

Geography

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