Using artificial GPS

Hello everyone. I am working on a project that involves replacing the normal GPS data stream with an artificial data stream that acts like GPS. To do this requires that the location sentences interpreted by the firmware have to be identically the same, or at least that seems like the logical approach. Where in the firmware is the code that receives the GPS sentences? What GPS sentence format is used? Is there any information from others who have done this sort of work?

I’d be interested in any help available.


you can use