Mark Borgerson wrote in
.net:

"For civilian L1-band applications, the GPS system is actually a simple
spread-spectrum communication system.4 Figure 2 shows the signal
generation block for civilian applications. First, the 50-b/s navigation
message is repeated 20 times to produce a 1000-b/s bit stream, then the
repeated signal is spread by a unique Coarse/Acquisition (C/A) code with
a length of 1023 chips (the rate at which the pseudorandom noise code is
applied). The result is a baseband signal of 1.023 Mchips/s. As a result
of this spread-spectrum approach, the total processing gain (G) of the
GPS system can resolve a signal well below the thermal noise level."



-159dbm....wow. Too bad the spread spectrum on the damned CDMA/GSM
cellular systems don't work that well. -105dbm and my cellphone goes dead.



Larry
--
VIRUS ALERT! VISTA has been released!
NOONE will be spared!