How to build your own GLONASS - gps alternative. http://hackaday.com/2007/10/04/build-your-own-gps-and-glonass-receiver/
If the Chinese zap our satellites with their laser, the Russians and India use this other system (which would probably be destroyed by debris from our destroyed satellites)
If the Chinese zap our satellites with their laser, the Russians and India use this other system (which would probably be destroyed by debris from our destroyed satellites)
