[aprssig] Appalachian Trail Tracking

[Arnie Shore]

Maybe a Q&D approach, along the lines we used n years ago - where n is
a LARGE number! - to detect aircraft failing a position check against
known flight plans:

1.  Design a grid scheme based on lat/long  - or use an existing one,
like UTM.  Grid dimensions per your convenience.

2.  Maintain a database table of the grids of interest.

3.  For each new or moved position report, check the db table against
its calculated grid number for presence/absence.  (A hash table could
work well here, vs an indexed DB table.)

The above might be less CPU-intensive than a proper distance
calculation, if that's what you're considering.  And, possibly,
perform the distance calculation for those that qualify per the above.

AS


On 3/1/12, John Gorkos <jgorkos at gmail.com> wrote:
> Well… This is a bit harder than I though.