[aprssig] Digital two-way Radio communication in emergency situations

Scott Miller scott at opentrac.org
Mon Sep 8 13:52:59 EDT 2014

On 9/8/2014 9:20 AM, Robert Bruninga wrote:
>> A new network ought to allow only users with... coordination
> capabilities.
>> You don't get to transmit without knowing the exact time... [slot]
>> The tricky part is coordinating slot reuse between overlapping digis...
> An easy fix for purpose built nets for special events is to eliminate that
> problem by using split freqs.  One for the trackers and the other for the
> digi outputs.  Just like we do here for local special events.  144.39 for
> digi outputs (so everyone can see everything and everyone) and +600 for
> tracker inputs.

That's not exactly what I meant... though for the Burning Man project I 
was working on slotted digis that would aggregate traffic over a 5 
second period and transmit everything within a dedicated 1-second digi slot.

The problem I'm talking about is if you have a digi acting as a channel 
access control authority and assigning slots to trackers.  You don't 
want the same slot on the same channel being used by different trackers 
in overlapping digi coverage areas.


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