| Notation | Description | Sample frequency (minutes) |
| Advanced ionospheric sounder (AIS) |
| fmin | Lowest plasma frequency recorded by AIS (MHz) | 15 |
| fEmax | Highest plasma frequency recorded from E-region (MHz) | 15 |
| fFmax | Highest plasma frequency recorded from F-region (MHz) | 15 |
| VLF/ELF experiments |
| VLF-1 | Mean, omni-directional logarithmic intensity of 1 kHz signal with 1 kHz bandwidth
(dB with respect to 10-33 T2 Hz-1) | 1 |
| VLF-3 | As above, but for 3 kHz signal with bandwidth of 1 kHz | 1 |
| Fabry-Perot interferometer |
| US | Line of sight Doppler velocity in magnetic south direction (ms 1) | 30 |
| UE | Line of sight Doppler velocity in magnetic east direction (ms 1) | 30 |
| Magnetometer |
| H | Northward component of field intensity (nT) | 1 |
| D | Eastward component of field intensity (nT) | 1 |
| Z | Vertical component of field intensity (nT) | 1 |
| Riometer |
| AS | Absorption in (dB) looking geomagnetically south | 1 |
| AN | Absorption in (dB) looking geomagnetically north | 1 |
| AE | Absorption in (dB) looking geomagnetically east | 1 |
| AW | Absorption in (dB) looking geomagnetically west | 1 |