Hi GPS is pretty close to the noise "as received". A fully passive system with significant cable loss and low / no gain antennas does not sound like it's going to do a very good job.
Bob -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jim Lux Sent: Thursday, April 12, 2012 9:52 AM To: [email protected] Subject: Re: [time-nuts] Best location for a GPS antenna...? On 4/12/12 2:09 AM, Rob Kimberley wrote: > There are commercial "re-radiators" for GPS. I found these on Google: > > <http://www.gps-repeating.com/?gclid=COTV88D6rq8CFcwTfAodhSKvmQ> > <http://gpsnetworking.com/GPS-re-radiating-kits.asp> > > > One of my old suppliers in the UK was marketing a range of these, but I seem > to remember some problem in getting approval in the UK, and they had to drop > them. Things may have changed as this was a few years ago. > Interestingly I've just been looking into this... Why would you need anything special to reradiate.. It's not like you need a particular antenna pattern or constant gain or something. What about something like a fat monopole against a ground plane, with a attenuator at the feed to provide a good terminating impedance for the LNA/Line driver. If it's L1 only, you don't even need particularly wide bandwidth (<1%) Yes, I've seen setups at JPL where they reradiate with D&M or Ashtech chokering antennas (or even helibowls), but that might be because we've got a bunch of them sitting around, so why not use it. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
