On 2/2/2011 7:25 AM, jimlux wrote:
I got the impression that it wasn't modeled, but was an actual field
test of some sort. I'll have to go back and reread.
But, it's possible that the consumer receiver has better multipath and
interference rejection, if only because it's newer. Aviation stuff
takes longer to go through the approval cycle, so it tends to lag
consumer electronics in terms of technology adoption.
From the paper submitted by the GPS manufactureres to the FCC
http://www.gpsworld.com/gnss-system/signal-processing/lightsquared-jamming-report-11030
it seems they simulated the Lightsquared signal with test equipment and
made measurements in an anechoic chamber of effects on GPS signal
reception to a couple of popular GPS receivers. Using this data they
extrapolated real-world effects with path loss calculations. Ironically,
it probably wouldn't be legal or safe to make the jamming measurements
in a real, open space, environment.
The paper says the Lightspeed transmitters can be up to around 15 kW
EIRP in a band right adjacent to GPS. I would think filtering out that
signal to avoid overload would be a daunting task.
_______________________________________________
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.
