A high power, low loss RF strip transmission line coupling structure is provided. It includes a multi-layer printed circuit board (PCB), a top cover and a bottom cover. The top and bottom covers provide the ground reference for the strip transmission line coupling structure. The PCB is fastened to the top and bottom covers and is used for: creating the center conductor of an air dielectric strip transmission line and edge coupler; providing a means to transition from microstrip to air dielectric strip transmission line; supporting the air dielectric strip transmission line; routing of other signals; and passing ground to the top and bottom covers. To create an air dielectric strip transmission line, the PCB material is adequately removed to effectively form a rectangular bar of dielectric and metal layers. This rectangular bar is plated along the edges where the PCB material was removed to ensure that the top and bottom PCB metal layers are at the same potential.