LPS

[edward]

I was thinking of setting up a Local Positioning System instead of using GPS. Would it be possible to use 3 or 4 smart phone bases around the lawn and one on the mower as the positioning system?

 

[AlexanderG]

Sure, you can use any time-of-flight signal (GSM, UWB, GPS, light etc.) between base stations and mower and then use trilaterateration to compute the position based on the measured times (=distances). Do you have any specific system in mind (any web link etc.)?