[time-nuts] Best location for a GPS antenna...?

[Jim Lux]

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.