MMS 1 DSP Electric Field Power Spectral Density, 16 s Slow Mode

The Magnetospheric Multiscale (MMS) mission's Digital Signal Processor computes electric field power spectral density (EPSD) from onboard probes. Data is derived from a 1024-point FFT algorithm, producing spectra with 56 pseudo-logarithmic frequency bins and a dynamic range over 120 dB. This Level 2 dataset from NASA is reported in slow mode, with rates from 16 spectra per second down to one spectrum every 16 seconds.

Use Cases

• Analyzing plasma wave properties based on power spectral density calculations.
• Studying magnetospheric phenomena using electric field measurements from double probes.
• Determining plasma density with narrow-band emission fits at ~3% accuracy.
• Investigating signal dynamics using data from nine simultaneously processed signals.

Strengths

• Data processing uses a 1024-point FFT with 48-bit accuracy for high dynamic range.
• Spectra are reduced to 56 frequency bins with (del f)/f between 6% and 12% for analysis.
• The system can process nine signals simultaneously, with six at 100% duty cycle.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Timing between measurement channels can be inaccurate by a fraction of a second.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Onboard computation by the Digital Signal Processor (DSP) using FFT on analog signals from Axial and Spin-Plane Double Probes.

Time Range

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Freshness

Last updated 2026-03-13 06:28:40.042201; freshness should be verified.

Geography

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