Does any open source software exist that can compute GPS ground coverage in real time? At work I used STK which would do the job perfectly, but I'm at school now so I only have the free version. For those who don't know STK can simulate the GPS constellation and determine how much coverage any particular Earth coordinates are getting. You can also place transmitters or jammers and see how that affects the coverage.
Unfortunately, the free version of STK doesn't come with coverage definitions or the ability to place new transmitters, which is what I need. Does anyone know of an open source software package that can simulate the GPS constellation, compute ground coverage, and allows placement of transmitters/jammers?
I read this question:
What are the choices today for orbital mechanics simulation software?
which had suggestions for orbital mechanics software. I was hoping that either the GMAT or ORSA software packages mentioned there might be able to do what I want, but it looks like they're more for space exploration stuff rather than GPS. If anyone has used these packages and knows if they can load the GPS constellation I'd love to hear about it.