The advanced, or differential, GPS has an margin of error of just 3.2 feet, compared with the 121 feet found in conventional GPS…. The advanced, or differential, GPS has an margin of error of just 3.2 feet, compared with the 121 feet found in conventional GPS. [Read more]
Read more http://feedproxy.google.com/~r/cnet/tcoc/~3/JZNaRgr2zG0/story01.htm