The TRX NEON Location Service delivers location and context for personnel operating indoors and underground where GPS is unavailable, in urban canyons, and in locations where GPS is intentionally jammed. Wearing NEON Tracking Accessories, personnel can be located in real time in both 2D and 3D. The NEON API allows receipt of location constraints from user or partner applications, and provides 3D location, error bound information, and posture.