Originally Posted by
Shadoko
Is there anybody who understands why the same line of data is repeated? For example, on page 10, there are 26 lines of data, 23 of them identical. Has this a meaning?
Long SATCOM messages will presumably be split into the initial signal unit that identifies the type of message, and multiple subsequent signal units containing the rest of the data. Could also be retransmissions, but I'd expect to see some kind of 'NAK' message from the aircraft before anything was retransmitted.
Another question: it seems that all the BTO times last digit are 0 and the penultimate are even. Could we state the time is filed with a 20 µs step?
Hadn't noticed that until you mentioned it, but it seems likely. Given the low bit-rates of the channels, I'm not sure you could measure it to microsecond accuracy. That would also be consistent with the 10km accuracy mentioned in the 'considerations on defining the search area' document. Twenty microseconds looks like about 6km to me.