Methods, devices, and uses for calculating a position using a global navigation satellite system

A method for creating a three-dimensional representation of terrestrial objects in an urban area, comprising:

• by a server computer, obtaining from a receiver receiving global navigation satellite signals, a plurality of positions and a respective plurality of strengths of signals received by said receiver at each of said plurality of positions from a satellite;
• by said server computer, identifying among said obtained positions, based on said obtained strengths, positions at which a status of said satellite changes from a line-of-sight (LOS) satellite to a non-line-of-sight satellite (NLOS), and defining said identified positions as contour edge points;
• by said server computer, using said identified positions to identify three-dimensional contours of terrestrial objects in said urban area, such that two-dimensional contours of said terrestrial objects are bounded by said contour edge points;
• and
• transmitting over a wireless network, at least a portion of said three-dimensional representation of said terrestrial objects to one or more GNSS receivers.

A method for transmitting a three-dimensional representation of an area, to a GNSS receiver, for improving calculation, comprising:

• at a fixed location, calculating by a server computer a shading three-dimensional representation of an area at a first rate;
• over a wireless network, receiving, by said server computer at said fixed location, from a GNSS receiver an indication of a location of the GNSS receiver, said location being included in said area;
• and
• transmitting over said wireless network a portion of said shading three-dimensional representation corresponding to a portion of said area from said server computer at said fixed location to said GNSS receiver at a second rate, wherein said portion of said area contains said received location, and said portion of said shading three-dimensional representation includes a three-dimensional representation of said received location.