[aprssig] IGate FIlter for AMSATS?

Pete Loveall AE5PL Lists hamlists at ametx.com
Sat Feb 25 15:09:29 EST 2017


Not really.  The issue you have is footprint of a satellite.  In terrestrial VHF/UHF communications, we rely on IGates being separated by enough distance to "reduce" collisions.  I put "reduce" in quotes because there are a lot of other factors involved but that is a basic concept.  With a satellite, if you had bidirectional IGates, you would have constant collisions as multiple IGates see the same station via the satellite rendering most messaging useless as they would not get through the satellite.  Can you send a bulletin, set your Mic-E to Emergency, etc.?  Absolutely since those will be passed to APRS-IS.  Can you do standard messaging? No because SatGates are receive-only and this is a concept dating back to the earliest of SatGates.  Same reason we don't gate from APRS-IS to HF.

Hope this helps.

73,

Pete Loveall AE5PL
pete at ae5pl dot net


> -----Original Message-----
> From: jess at jesshaas.com [mailto:jess at jesshaas.com] On Behalf Of Jess Haas
> Sent: Saturday, February 25, 2017 1:49 PM
> To: Pete Loveall AE5PL Lists <hamlists at ametx.com>
> Cc: TAPR APRS Mailing List <aprssig at tapr.org>
> Subject: Re: [aprssig] IGate FIlter for AMSATS?
> 
> Is there a better solution that would actually allow for two way messaging via
> satgate? Im thinking something along the lines of the gates communicating
> with/via APRS-IS to make sure not too many try to gate the same packets to RF.
> This same functionality could allow for a higher density of two way igates on
> regular APRS to allow better coverage and redundancy without flooding the
> airwaves.


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