It's interesting that there are amateur satellite allocations in the 2.4 GHz and 5 GHz ranges as well. A number of groups are doing ham internet on those frequencies using modified routers. This might be an option for some kind of digital satellite, although dealing with doppler could be a problem. I can envision an amateur version of Starlink.
-Stephen, N8URE
Besides Doppler shift, which would definitely be a problem, there's also the WiFi protocol itself. It's designed for short range communication, and some of the low level protocol timers need to be adjusted for working in WAN applications such as AREDN. I suspect that getting them to work over orbital distances might be an ack retry too far.
Greg KO6TH
Stephen DeVience via AMSAT-BB wrote:
It's interesting that there are amateur satellite allocations in the 2.4 GHz and 5 GHz ranges as well. A number of groups are doing ham internet on those frequencies using modified routers. This might be an option for some kind of digital satellite, although dealing with doppler could be a problem. I can envision an amateur version of Starlink.
-Stephen, N8URE _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
I started working on a linked, peer-to-peer, voice communications network for amateur satellite service, called amsalLink. Unfortunately, the closure of the AMSAT office due to COVID-19 has doubled my volunteer workload and forced me to put the project on hold.. There are throughput limitations in satellite links for data communication. TCP senders cannot exceed the rate at which the receiver can acknowledge receipt of packets, where satellite latency effectively caps standard TCP throughput per session. TCP Spoofing, which imitates a terrestrial TCP session by sending false TCP packet acknowledgements, is one possible solution. Since my focus was to develop a voice chat, I have chosen to use UDP to overcome acknowledgement limitations. My amsatLink project is described in the March/April 2020 issue of The AMSAT Journal and https://ke4al.github.io/amsatLink/ Robert, KE4AL
On Thursday, July 23, 2020, 05:16:36 PM CDT, Greg D via AMSAT-BB [email protected] wrote:
Besides Doppler shift, which would definitely be a problem, there's also the WiFi protocol itself. It's designed for short range communication, and some of the low level protocol timers need to be adjusted for working in WAN applications such as AREDN. I suspect that getting them to work over orbital distances might be an ack retry too far.
Greg KO6TH
Stephen DeVience via AMSAT-BB wrote:
It's interesting that there are amateur satellite allocations in the 2.4 GHz and 5 GHz ranges as well. A number of groups are doing ham internet on those frequencies using modified routers. This might be an option for some kind of digital satellite, although dealing with doppler could be a problem. I can envision an amateur version of Starlink.
-Stephen, N8URE
_______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
participants (3)
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Greg D -
Robert Bankston -
Stephen DeVience