[aprssig] Bug or feature: ambiguity circles that expand with dead-reckoning distance?

[Andrew P.]

Greetings, all.

I was fixing what looked like a bug in my APRS client software when it hit me: is it really a bug to increase ambiguity for a moving station when displaying a dead-reckoned position for that station instead of the last reported position?

The particular "bug" I had showed the ambiguity circle as having a center at the dead reckoned position and the circumference intersecting the last reported position (ie., the station might never have left the last reported point). This was for a last position report with full precision so an unaltered ambiguity circle would have been invisibly small).

So, what is the collected wisdom on this? Is this a bug or a feature?

Just curious.

Andrew Pavlin, KA2DDO
Sent from my Verizon Wireless BlackBerry