1. An image generating device comprising: an image former comprising a computer-readable media storing code executable by a computer processor of a computing system, the computing system coupled to a radar that is operable to transmit and receive electro-magnetic radiation at a plurality of frequencies in the range of 500 Mega-Hertz to 3 Giga-Hertz, the image former operable, at each of the plurality of frequencies, to: receive, from the radar, the electro-magnetic radiation reflected from a building; generate an image of the building from the received electro-magnetic radiation; and adjust the image according to a plurality of material characteristics of a wall of the building, the plurality of material characteristics comprising a thickness of the wall and a dielectric constant of a material from which the wall is made; and wherein the image former is further operable to: combine the images generated at the plurality of frequencies to form a resulting image, the resulting image having a plurality of contiguous regions that overlap one another; and apply a phase gradient factor to the plurality of contiguous regions, the phase gradient factor comprising an electro-magnetic radiation phase difference between adjacent samples of each of the plurality of contiguous regions.