[Asus  Eee Pad Transformer Prime] BarryH_GEG:
I guess it depends on what everyone's definition of a GPS "fix" is. Some Prime's get no signal whatsoever which most likely is do to the antennas which is h/w. Those that get signal can't use the device for navigation because the metal back cover doesn't allow a consistant enough signal for the chip to keep up with the satelllites when it's in motion.

GPS signals are weak and very sensitive to interference. Software's not going to be able to overcome that. Lot's of "good" Prime's pick up satellites, even indoors. There's some vids posted of both Prime's and G-Tab's using Google Nav and CoPiliot. The results aren't even close. And all s/w does is help the chip lock faster. Once its locked, it's up to the chip itself to maintain the signal. If it can't, no s/w in the world can compensate for that.

"Assisted GPS, generally abbreviated as A-GPS or aGPS, is a system which can, under certain conditions, improve the startup performance, or time-to-first-fix (TTFF) of a GPS satellite-based positioning system. It is used extensively with GPS-capable cellular phones as its development was accelerated by the U.S. FCC's 911 mandate making the location of a cell phone available to emergency call dispatchers."[1]

http://en.wikipedia.org/wiki/Assisted_GPS

This is from Garmin...

"GPS satellites transmit two low power radio signals, designated L1 and L2. Civilian GPS uses the L1 frequency of 1575.42 MHz in the UHF band. The signals travel by line of sight, meaning they will pass through clouds, glass and

plastic

but will not go through most

solid objects

such as buildings and mountains."

Sources of GPS signal errors

Factors that can degrade the GPS signal and thus affect accuracy include the following:

◦Ionosphere and troposphere delays - The satellite signal slows as it passes through the atmosphere. The GPS system uses a built-in model that calculates an average amount of delay to partially correct for this type of error.

◦Signal multipath - This occurs when the GPS signal is reflected off objects such as tall buildings or large rock surfaces before it reaches the receiver. This increases the travel time of the signal, thereby causing errors.

◦Receiver clock errors - A receiver's built-in clock is not as accurate as the atomic clocks onboard the GPS satellites. Therefore, it may have very slight timing errors.

◦Orbital errors - Also known as ephemeris errors, these are inaccuracies of the satellite's reported location.

◦Number of satellites visible - The more satellites a GPS receiver can "see," the better the accuracy. Buildings, terrain, electronic interference, or sometimes even dense foliage can block signal reception, causing position errors or possibly no position reading at all. GPS units typically will not work indoors, underwater or underground.

◦Satellite geometry/shading - This refers to the relative position of the satellites at any given time. Ideal satellite geometry exists when the satellites are located at wide angles relative to each other. Poor geometry results when the satellites are located in a line or in a tight grouping.

◦Intentional degradation of the satellite signal - Selective Availability (SA) is an intentional degradation of the signal once imposed by the U.S. Department of Defense. SA was intended to prevent military adversaries from using the highly accurate GPS signals. The government turned off SA in May 2000, which significantly improved the accuracy of civilian GPS receivers.

http://www8.garmin.com/aboutGPS/