I can’t understand exactly what the difference is between calculating the heading as the difference between two gps points using two Ardusimple cards and reading the heading (UBX-NAV-RELPOSNED) using two cards in moving-base mode
Are there differences in the accuracy of the calculated / read direction?
Maybe the only difference is the absence of a CPU to calculate the direction as the difference between two gps points?
It’s only a mathematical difference, it’s slightly more accurate to calculate relative positions from 2 devices next to each other, than from 2 devices each of them 1km away from the base station.
Also the advantage of moving base is that the connection is usually wired, so you don’t have the risk of losing accuracy because there is an interruption in corrections from the base station.
Lastly yes, you need an external CPU to calculate the difference between 2 rovers connected to the same base station.