[aprssig] APRS Speed Spec? (plan B)

Kenneth Finnegan kennethfinnegan2007 at gmail.com
Wed Oct 11 16:07:40 CDT 2017

On Wed, Oct 11, 2017 at 1:20 PM, Jason KG4WSV <kg4wsv at gmail.com> wrote:

> 999 - speed is 999 or greater.
> done.

I'm going to agree with Jason on this one.

What is the purpose of encoding very coarse higher velocities? If something
has a satellite or jet symbol and an altitude of "really high" I don't
think we need to have the ability to encode exactly how bloody fast it's
going. It's going to be over the horizon before you finish looking up what
range of speeds 997 is anyways.

If anyone really cares more than "greater than 999" they probably care more
than "1,600-15,000 knots" and will want to add "/VEL=XXXXXknots" in their
status text.

There's also all the speed differences between LEO, space station, GPS, GEO
orbits for various orbit configs, but it's not like I think we should try
and support all of those anyways. At some point encoding the keps makes
more sense than heading and velocity...

Kenneth Finnegan

On Wed, Oct 11, 2017 at 1:20 PM, Jason KG4WSV <kg4wsv at gmail.com> wrote:

> how about:
> 999 - speed is 999 or greater.
> done.
> if you need better resolution, switch to hex (max 4095 in decimal) or
> base92 (~779000), which is no more nuts than what you propose. Since
> you're forcing the app developers to code, maximize the usefulness of
> the kludge.
> or add a /S=N extension, where N is one or more digits representing
> speed followed by whitespace or end of packet.  That way your max
> speed is bounded by the length of the packet.  or c.
> -Jason
> kg4wsv
> _______________________________________________
> aprssig mailing list
> aprssig at tapr.org
> http://www.tapr.org/mailman/listinfo/aprssig
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.tapr.org/pipermail/aprssig/attachments/20171011/a40e5185/attachment.html>

More information about the aprssig mailing list