Red Point Positioning has, for the last three years, been developing a GPS-like tracking system for people and resources on a job site. With the unit looking to be available in the first quarter of 2016 all indications from early testers is that the program is exceptional.
Using an ultra-wideband frequency the system transmits through walls and achieves horizontal location accuracy to within 8 inches. Transmitter/receiver nodes need to be spaces out about 50 meters apart on the job site for the system to work. Read more here.