It is because of the processing gain and I believe these to be normal figures. Not an expert here but when the system de-spreads the signal the information pops up above the noise since the noise is random and the spread carrier only appears random. Regards Paul WB8TSL
On Fri, Sep 26, 2014 at 7:22 AM, Andrea Baldoni <erm1ea...@ermione.com> wrote: > On Fri, Sep 26, 2014 at 10:07:56AM +0100, Dr. David Kirkby (Kirkby > Microwave Ltd) wrote: > > > I don't understand the units of signal strength > > > > "The L1 carrier is spread over a 2 MHz bandwidth and its strength at the > > Earth's surface is -130 dBm. Thermal noise power in the same bandwidth is > > -111 dBm" > > > > Then goes on to talk about the signal being 20 dB below the noise. > > Hello David. > > It could be because there is a "process gain" associated in demodulating a > spread spectrum signal. > > Best regards, > Andrea Baldoni > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
