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Update 'WSPR Message Coding'

Sebastian 2021-05-08 17:41:53 +00:00
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commit c96d9fec5a
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WSPR-Message-Coding.md

@ -47,6 +47,15 @@ Basically a large 50bit number with differntly weightened digits.
| Locator longitude | 180 | `128` | Longitude from locator 0-358 in 2° steps |
| Power and Type | 128 | `1` | Tranmission power and message type |
There is discontinuity between the last position of the call sign an the locator because the original WSPR code
seems to be intended for 32bit machines.
All possible callsign representations fit into 28bit,
but neither the locator nor the power fits easily in the reamining 4bit.
Therefore they had to be assembled in in a different 32bit word.
There are `128*180*180 = 4147200` possible combinations of locators and power,
which is close enough to `2^22 = 4194304`, to waste a few values by aussiming the callsign is shifted by 22bit,
when combining the values.
Prefixed Callsign Message
-------------------------