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Iridium Toolkit
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Frame Format
Frame Header
All (parsed) frames start with a header:
IRA: i-1472473197-t1 000001626 1627088000 97% 0.009 129 DL
| Field Number | Content | Example | Comment |
|---|---|---|---|
| 0 | Frame type | IRA: | |
| 1 | UNIX timestamp in seconds when the recording started | i-1472473197-t1 | The i- prefix and -t1 suffix a historical artefact… |
| 2 | Time in milliseconds inside the recording | 000001626 | |
| 3 | Frequency in Herz | 1627088000 | Estimated center frequency |
| 4 | Confidence in percent | 97% | Confidence is estimated during demodulation by gr-iridium |
| 5 | Signal level | 0.009 | Arbitrary scale |
| 6 | Length in symbols | 129 | Excluding the 12 symbol sync word. One symbol equals two bits |
| 7 | Direction | DL | DL or UL |