[aprssig] future positioning parameters - geohash

[Chris Kantarjiev]

For anyone that has time to contemplate alternate position notation 
systems for APRS, it might be interesting to look at geohashes:

http://geohash.org/
http://en.wikipedia.org/wiki/Geohash

It's a not-very-computationally intensive system for managing a 
hierarchy of location specifications; ambiguity is built in. The 
representation is very compact (but not human readable). Geohashes offer 
properties like arbitrary precision, similar prefixes for nearby 
positions, and the possibility of gradually removing characters from the 
end of the code to reduce its size (and gradually lose precision).

It's not clear to me that trackers would necessarily want to use this 
(though I think it would be fine to do so, especially since there is a 
well-defined mechanism for providing ambiguity) but other systems 
upstream from the raw packets might find it a useful representation.

73 de chris K6DBG