GPS with GLONASS
 

Said to have accuracy to the inch...Don't know how soon but dam thats amazing!

What I read.

The GLObal NAviagation Satellite System (GLONASS) is a Russian system. When operating in its full configuration, GLONASS has three orbital planes of eight satellites each. This makes a total of twenty-four satellites, plus orbital spares. Each orbital plane is inclined 65 degrees to the equator. The satellites orbit Earth roughly every 11 hours, at an altitude of 19,140 kilometers.

GLONASS is similar to GPS in scope. There are differences in orbital geometry allow GLONASS to provide slightly better coverage at far northern latitudes.

Today, GLONASS has 13 operational satellites and one spare on-orbit. A complete GLONASS constellation has been on-orbit, and the Russian government has gone on record that it intends to support and maintain the GLONASS system. Presently, several additional GLONASS satellites have been built and are ready for launch.

GLONASS, like GPS, uses frequencies in the L-band. unlike GPS, GLONASS uses separate frequency bands for each satellite. GLONASS is based on a different time standard, and uses a different model of Earth. Each satellite has a civil frequency for non-precise uses and a military frequency with higher-precision data. Unlike GPS, GLONASS does not have Selective Availability, so the civil accuracy is approximately 20 to 30 meters horizontally with a full GLONASS constellation.

When GPS is augmented with GLONASS, a potential full constellation of 48 satellites would be available for use. Today, 40 satellites are available. Ashtech, a GPS vendor, has not only succeeded in creating sensors that augment GPS with GLONASS but uses the different GLONASS L1 frequencies in combination with GPS L1 to provide an RTK sensor with centimeter accuracy

So I bet there would be a subscription fee that is paid for Glonass just like we now pay to Omnistar where we get 2-4" accuracy. Or like we pay for an RTK radio signal to get sub inch accuracy. I wonder how much it will be?