Circular Dielectric Waveguides for D-Band Applications in Communications and Radar

Dielectric Waveguides (DWGs) are mechanically flexible, lightweight and potentially very cost-effective. For the preferred low-loss materials like PE (Polyethylene) or PTFE (also known as Teflon) the required inner core’s diameter of circular DWGs is a bit less than the free-space wavelength, and the lower-permittivity cladding’s diameter is typically 2.5 to 3 times the core diameter [1]. This results in a cable diameter of only a few millimeters (5…7 mm) if we operate the DWG within the D-Band frequencies (i.e., 110-170 GHz). On the other hand, the losses of such waveguides increase more or less linearly with the frequency. Therefore, in terms of manufacturability, size, and performance, we believe that the D band is an optimal choice for DWG-based interconnections, if their length is in a range of approx. 1 … 30 meters.