A thermal signal generating device, including at least two parallel buss bars operable for carrying a current and a heating element having at least a first region and a second region. The heating element includes a plurality of horizontal traces and a plurality of vertical traces. Widths of each of the plurality of horizontal and vertical traces may be greater in a first region of the heating element than in a second region of the heating element, allowing for a gradient heat differential to be emitted by the heating element.