[aprssig] APRS vs. SPOT

John Gorkos jgorkos at gmail.com
Thu Sep 8 07:35:42 CDT 2011

On 09/07/2011 05:35 PM, jjesson at voyager.net wrote:
> From my ~10 years of designing-in commercial satellite/cellular 
> tracking and telematics systems:
>   SPOT technology originally was designed by Axonn's then CTO and this 
> technology is based on simplex protocol talking to Globalstar.... 
> protocol is interesting as it chips between Globalstar's native CDMA 
> duplex protocol (native to Globalstar). Their form of simplex is also 
> known as send-and-pray as not an ARQ protocol with Simplex... but a 
> form of repeat packet transmissions improve the odds of correctly 
> receiving packets and this is a setting in their engineering 
> configuration tool.
Just out of off-list curiosity, who was Axxon's CTO?  There were a slew 
of super smart guys working there.

John Gorkos

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