"Ever since the SiRFstarIII chipset set the bar for high sensitivity
GPS receivers in early 2005, the competition had only been able to
equal its -159dBM sensitivity, but the new MTK vII (MTK 3329) chipset
is rated at -165dBm. While 6dBm may not seem a lot, it actually
computes to an x4 boost in sensitivity! Hard to imagine what that
translates to in the field, but we should soon find out since it
powers the new Qstarz Nano GPS receivers.

The Nano BT-Q890 is a standard Bluetooth GPS receiver while the
BT-Q1300 adds a 200,000 point datalogger. Ultra sensitive and ultra
compact..."

http://www.gpspassion.com/fr/news.asp?id=439

On Mon, 30 Jun 2008 19:14:48 GMT, Sam Wormley
wrote:

Keith wrote:
"Ever since the SiRFstarIII chipset set the bar for high sensitivity
GPS receivers in early 2005, the competition had only been able to
equal its -159dBM sensitivity, but the new MTK vII (MTK 3329) chipset
is rated at -165dBm. While 6dBm may not seem a lot, it actually
computes to an x4 boost in sensitivity! Hard to imagine what that
translates to in the field, but we should soon find out since it
powers the new Qstarz Nano GPS receivers.


http://www.gpspassion.com/fr/news.asp?id=439

Be aware that a significant source of error are multipath
signals... so with reverse polarization and some not.

Increasing GPS receiver sensitivity can play havoc with
mutlipath mitigation. Please do not blindly assume that
the MTK vII (MTK 3329) will perform any better than the
SiRFstarIII.

All good points, I certainly don't, we all remember how long it took
for SiRF to get a handle on the sensitivity boost brought by the
SiRFstarIII hardware, something like a year. Still, MTK did an
excellent job with their v1 chipset so let's give them the benefit of
the doubt at this point.

-Sam Wormley
http://edu-observatory.org/gps/gps_accuracy.html