This is my general idea
That is certainly not an original idea.
People have been doing those sorts of experiments in idealized environments for over a decade, with little useful success.
The top paper in this list, a research paper from 2008 demonstrates the technique, using the same arrangement of nodes that you propose, outdoors in an obstacle free environment, with carefully positioned antennas all in the same orientation.
However, the technique does not work in the real world, or any place where it would actually be useful, or you would be able to buy cheap devices that use it.