I was close An average of 14 minutes, 6 seconds will be required for signals to travel between Earth and Mars.
"Mars-Earth distance in light minutes"<http://www.wolframalpha.com/input/?i=mars+earth+distance+>. WolframAlpha. Retrieved August 6, 2012. On Fri, Aug 10, 2012 at 1:36 PM, Brian Lloyd <[email protected]> wrote: > On Fri, Aug 10, 2012 at 10:48 AM, bill <[email protected]> wrote: > > > How long does it take from the time Curiosity takes a pictures/processes > > it for transmission to reception by NASA? > > > > Is the picture sent in segments and does NASA use a 'checksum' type > system > > to make sure of proper reception. > > > > Today's pics were better than I took of my dogs yesterday, and they were > > just a few feet away from me lying in my lawn! > > > > I presume you want a serious answer. No, they do not use a "checksum" > system because it takes too long to send back a NAK to say, "sent that one > again." (It is a 20+ minute round trip for the radio signal.) They actually > use forward error correction with enough redundancy so that, when the bits > arrive back on earth, even if some of them are wrong, the receiver can > correct the errors so an error-free data block (or part of a picture) is > recreated in the receiver. > > In ham radio we have a couple of systems that work this way, e.g. Olivia, > MFSK16, Contestia, DominoEX/FEC, Thor, MT63, JT65, WSPR, etc. That is why > they get good copy on a poor signal without having to retransmit the data. > > -- > Brian Lloyd, WB6RQN/J79BPL > 3191 Western Dr. > Cameron Park, CA 95682 > [email protected] > +1.767.617.1365 (Dominica) > +1.916.877.5067 (USA) > _______________________________________________ > Flexedge mailing list > [email protected] > http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz > This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is > used for posting topics related to SDR software development and > experimentalist who are using beta versions of the software. > -- Doc Bill Dailey KXØO _______________________________________________ Flexedge mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used for posting topics related to SDR software development and experimentalist who are using beta versions of the software.
