[aprssig] WIDEn-N question
Robert Bruninga
bruninga at usna.edu
Wed Nov 4 08:41:42 EST 2009
> I also encourage the Big DIGI's not to
> respond to WIDE1, because they will pick
> up the WIDE2. Responding to both, the
> Big DIGI transmits twice.
Actually I need to clarify that.... There are several issues
here:
1) If the big digi does not respond to W1-1, then the big digi's
are ignoring ALL mobiles in its footprint that are not covered
by a fill-in WIDE1-1. And since the big digi's have probably 10
to 100 times the coverage of the small fill-in's, then this
approach essentially castrates the big digis... The big digis
have to respond to both for this system to work.
2) Under New-N paradigm, the big digi's will never digi any
packet twice. If they hear it first, they do the W1-1 and then
wont do the W2-1 later. If the W1-1 hears it first, then the
big digi will only do the W2-1 once also.
3) Even if both the big digi and the fill-in hear it at the same
time. Both will TX at the same time (Dwait=0) and no one will
hear the W1-1 because the big digi will saturate the whole area.
That is the beauty of the W1-1,W2-1 two hop system. It works.
And it only takes up ONE slot time at each outward tier, yet it
can use a Fill-in if that is all that hears it.
And there are no dupes causesd by it. Evey digi will digipeat
it once and only once. That is the intent.
> I also encourage Fill In DIGI to just respond to WIDE1-1.
Yes, that is essential.
> I recommend WIDE1-1,WIDE2-2 for mobiles in WPA.
Great!
Bob, WB4APR
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