How does the unit handle temporary obstructions?
The unit does “track” certain metrics that give it “confidence” in the GPS accuracy. If it sees a down-tick in overall confidence, it usually will wait up to a few seconds for the confidence to get better (many variables in the algorithm). In the situation described, in simplified terms, it would usually postpone the transmission for a few seconds. However, if it has a fix at all, it has “bail out” criteria that will transmit whatever it has eventually (well within the 10 minute window between messages in Track mode or the 5 minute window in SOS/9-1-1 or Help modes) even if the various “confidence criteria” metrics are failing to settle down. If it is “time to report” (10 minute interval in track, 5 minute in SOS/9-1-1 or Help), and it gets a fix, and just before it transmits the GPS signals disappear entirely, it will wait a few seconds, then if the signals don’t return, it will transmit the last GPS co-ordinates it had.
